RA.1778/DA78r20lB
HF CommunicationsReceiver
(Chapters17to 25)
EtBAntr
Racal Communications Limited WesternRoad,Bracknell,
RG121RG England
Tel: Bracknell(0344) 3244 Telex: 848166 Grams: RacalBracknell.
The Electronics GrouD Preparedby Central Handbooks Department,Racal Group Services Limited.
pr;nra.r
AP I l6E-0754-6B
Jon. 82 (Amdt3)
ggrt-ltNLr
PARI I
]ECHNICALSPECIFICATION
D
CHAPTER
I
PRINCIPLES
OF OPEMTION
CHAPTER
2
LOW FREQUENCY
LOOPBOARDPMsBB
CHAP]TR
3
UPPER
LOOPBOARDPM589
CHAPTER
4
TRANSFER
LOOPBOARDPS.33B
CHAPTER
5
HIGHFREQUENCY
LOOPBO,\RDPS.337
CHAPTER
6
34 MHzGENERATOR
BOARDPM339
CHAPTER
7
FREQUENCY
STANDARD
ASSEMBLY
CHAPTER
8
R FU N I T
CHAPTER
9
FIRST
MIXERBOARDPM335
CHAP]IRIO
SECONDMIXERBOARDPM336
CHAPTER
II
IF FILTER
BOARDPS.367
CHAPITR12
lFlAF BOARDPM364
CHAP]ERI2A
tFlAF BOARDPM674
CHAPIER13
SHAFTENCODER
CHAPTTR
14
DISPTAY
BOARDPM592
CHAPTER
15
DECODER
BOARDPA/694
CHAPTER
16
MEMORYBOARDPM693
{
PART2
CHAPTER
17
AFCBOARDPA4664
CHAPTTR
IB
FSKDEMODULATOR
BOARD
PM368
CHAPTER
19
pM370AND p5427/1)
POWER
SUppLtES
(|NCLUD|NGBOARD
CHAPTTR
20
CHAPTTR
2I
IN TERCONNECTIONS
AND CHASS
IS LAYOUT( INCLUDING
BOARD
PM4I9)
DISMAN'TLING
AND RE-ASSEMBLY
CHAPIER22
FUNCTIONAL
TtSTPROCEDURES
CHAPIER23
ALIGNMENT
PROCEDURES
RA,177BMointenonce
Contents(i)
AP 1t6E-0754-68
Jon.82 (Amdt3)
24
CHAP]ER
DIAGN05ISAND OSCILLOGRAMS
FAULT
CHAP]IR
25
LISTOF COMPONENTS
1
SUPPLEMENT
TO TTLLOGIC
INIRODUCTION
SUPPLEMENT
2
TOCMOSLOGIC
INIRODUCTION
SUPPLEMENT
3
ALTERNATIVE
LOGICSYMBOLS
4
SUPPLEMENT
AMPLIFIERS
TO OPERATIONAL
INTRODUCTION
5
SUPPLEMENT
TTCHNIQUES
REPAIR
APPENDIX
A U D I OS W I T C H I NUGN . T M M . 5 3 2
APPENDIX
2
AIR-24
SOLIDSTAIEFSKRELAY
APPENDIX
3
NOTAPPLICABTT
APPENDIX
4
MS56I
MODUTT
IFCONVERITR
RA. 1778Mointenonce
(ii)
Contents
C H A P T E RI 7
A_F_C__B_9AiD__P_MbbA
CONTENTS
Poge
INTRODUCTION
lnputAttenuotor
ondAmplifier
Mixer
400kHzAmplifier
AGC Detectorond Amplifier
Signo| -to-Noise Detector
I MHz Generoior
PhoseComporotor
Divide-by-F ive Stoge
Digitol Mixer
2kHz Oscilloior
Binory Counter
Di gitol -to-Ano logue Converter
TuningIndicotor
Conirol Monostoble
AFC Lock Lomp
ON-OFF Switchins
Adiustments
17-1
1 7- 1
1 7- l
t7-l
t7-l
17-2
17-2
17-2
17-3
t7-3
t7-3
17-3
17-4
t7-4
t7-4
17-4
17-5
17-5
ILLUSTRATIONS
Fig. No.
,AFCControlSystem
FunctionolDiogroms:
Loyout:AFC boordPM664
Circuii: AFC boordPM664Sht. I
Circuit: AFC boordPM66/Sh+.2
17.1
17.2
17.3
1 7. 4
Chopter17
RA.1778Moinlenonce
Contents(i)
gIrAP=lEL=Li=
AF C BOARD PM664
CIRCUIT DESCRIPTION
INTRODUCTION
l.
The circuii diogromof the AFC boord is given ot the end of this Chopter ond for
convenienceis on two sheets;Figs. 17.3 ond 17.4.
lnputAttenuotorond Amplif ier
The l.4MHz corriersignol is opplied to on lF omplifiervio on ottenuotorwhich
is conlrolledby the front ponel AFC switch. When this switch is sei io FULL
on eorth is opplied io boordpin 14; when the swiich is sei to PILOTCARRIER
CARRIER,
the eorth is removed. The eorth signol controls the tronsmissiongote swiich ML'l so thot
or 20dBottenuotedsignol (FULLCARRIER)
signol (PlLoT CARRIER)
eirheron unottenuqted
logic invenion
is opplied to the l.4MHz lF omplifier. MLI olso performsthe necessory
on the input from the AFC switch,
2.
The lF omplifier comprisesML2 ond ossociotedcomPonenisond incorporotesoutomoiic goin conirol of opproximotely38dB. The output is possedthrougho cryatol
filter to removeout-of-bondsignol components.
3.
Mixer
' The l.4MHz signol is mixed
The mixer consistsof ML3 ond ossocistedcomponents
produce
the
circuit is iuned to ihis
o
output;
reference
io
400kHz
o
lMHz
with
qnd
R36ond the conversion
frequency by L4 ond C20, Bios is provided by R3l, R33, R35
goin is deierminedby R34, M9 is odiustedto bqlonce the mixer so ihot the lMHz signol
is suppressed
.
4.
The 400kHz signol from ihe mixer is opplied to the input of ML4, which provides
O ro 3BdBof outomoticollycontrolledgoin. The omplifiedsignol is 'bufferedby
TR3ond TR4ond opplied tc the wqveformshopercomprisingTR5ond TR6, connectedos
o long-toiled poir. The woveformshoperocts os o zero -crossingdetector ond provides
on outputsuitqblefor driving CMOS logic.
5.
AGC Detectorond Amplifiers
6.
A proportionof ihe 400kHz signol is token from ihe buffer output ot TR4emitter
vio C27 qnd fed to the AGC detector. Theo.c. signol is reciified by
t7-1
RA.l778Mointenonce
diode Dl , producingon AGC volioge oi its coihodeequol to ihe peok volue of ihe o.c,
signol plus 6 volts. The AGC volioge is filtered ond omplifiedby ML5A; o d,c. offsei
is introduced,sei by R5. The AGC time constonts
ore set by R20, R22ond Cl6 to
provideon oitock time of opproximotely150 mS ond o decoy time of opproximotelyI .55.
The AGC voltoge con be dumpedby opplyingo logic '0'to boordpin 17, which turnson
TR2ond dischorges
Cl6; otherwiseii is opplied to the distributionomplifiersML5B,
ML5C ond ML5D. R37ond R4l motchthe AGC volioge derivedfrom ihe corrier with
ihe moin receiverAGC. R37setsthe slopeof the corrierAGC choroclerisiicond R4l
offsefs the ouipui voltoge so thoi it is obout 80 mV below the moin AGC voltoge, correspondingto q l0 dB signolchonge, The corrier AGC is oppliedto ihe moin AGC lineson
the lFl ond lF2 boordsond only iokes controlwhen ihe peok signol level folls by l0 dB.
1
Signol-to-Noise Detector
7,
MLl0o comporesihe peok signol volioge from ihe 400 k*z buffer stoge with o
level presetby the potentiol divider Rl 13, R45 (which providesthe odiusimenr)
ond Rl14. The outputfromMLl0o is opplied to the comporotor
MLl0b vio timing
componentsto produceo fost-decoy-slow-oliock chorocteristic;the AFC is inhibiteo
immedioiely if the corrier disoppeorsond is not enobled until obout 70 mS ofter the
corrier returns, R45is odiustedfor AFC presenion obout I ,5 pV e.m.f ,signol, ot which
level the LOCK lompiust flickers. The detectorolso inhibitsAFC oction if extroneous
signolspossthroughthe corrier filter,
'l
_
i
.-
J
MHz Generotor
B.
TR8 ond ossociofedcomponenisform o voltoge-controlled crystol oscillotor which
runsoi 7 MHz. The ouiput is convertedto TTL level by TR9ond opplied to the
input of ML7 which is connectedwith ML6 to form o divide-by-sevencircuit, The
resultont I MHz output is opplied to the 34 MHz boord, A smoll proportionof ihe signol
is omplifiedond convertedto CMOS level by TRl0.
PhoseComporotor
?.
The output from TRl0 is phose-compored
with the I MHz signol from the 34MHz
boord by o phosecomporoiorcomprisingMLI9 ond ML20 (o ond b), When the
AFC is switched OFF o phosedifference between ihe two signols produceso control
signol; ihis is filtered by R94, C55 ond C56, buffered by the voltoge follower MLl6o,
then opplied to ihe voroctor diode D4 in the I MHz generotor. ln this woy the I MHz
'l
generotor is phose-lockedio the MHz stondordso thqf when the AFC is first switcheo
ON the 34 MHz generotoris not so for off frequencythoi the corrier is shifted out of
the possbond
of the corrierfilter. SwitchingON the AFC inhibitsthe generotionof the
voroctor control signol by setting ML20b ond reseiting ML20o.
17-2
RA. |778 Mointenonce
\_-
j
Divide-by-Five Stoge
The I MHz frequencysiondordfromthe buffer TR7is opplied to the inputof
MLIB which is o divide-by-ten counierwired to divide by five, The resultont
2Q0k1z signol is producedoi fwo ouiPuts, Ql ond Q2' The phosedifference between
ihe Ql ond Q2 ouipuis is I ps which, ot 2Q0k1z, is 72o'
10,
Digiiol Mixer
The functionof the mixer is to produceoutpuisoccordingto the sign ond modulus
of the difference frequencybetweenthe 400 kHz corrier signol ond on occurote
400 kHz. The mixer, MLl7, is similorin operotionto o quodroturemixer with the exception ihot ihe clock runs ot 200 kHz ond the phosedifference is 72o- Both of these
they ore reloiively simple to derive from 1 MHz using o
volues ore chosenbecor.jse
divide-by-five counterond neitherolter the ouiput timing from ihot of o true quodroture mixer. The operotion is best undersioodby referencefo the timing diogroms,
I l.
R7O,R7l , R74 ond R75 provide hysteresisoroundthe mixer flip-flops to give
increcsedimmunityogoinsinoisyedgeson ihe corriersignol, while ony fost
doubfe edgesore filtered out by R79, C45, R78 ond C44. The edgesore speededup
o f t e rf i l t e r i n gb y M L l 2 p i n s8 , 9 , l 0 o n d ' l1 , 1 2 , 1 3 '
12.
Two ouiputs qi ihe difference frequencyore producedond fed to the clock ond D
inpuisof MLl3o, o D-type flip-flop' lf the corrierfrequencyexceedsihe referenceMLl3o is olwoysclockedwhen the D inpui is high, so its Q output is constonily
high. lf the corrier frequency is lower thon ihe reference MLl3o is olwoys clocked when
the D input is low, so iis Q output is constonllylow. ln ihis woy ihe sign of the difference frequencyis indicotedby ihe Q ouiputof MLl3o.
13,
14.
One of the differencefrequencyoutpuisis oppliedto the funing indicotorond
the oiher, togetherwith the sign indicoiion, is oppliedto ihe binory counter.
2 kHz Oscillotor
MLI4 pins B, 9, l0 ond ll; 12, 13 ore two CMOS invertinggotesbiosedinto
ihe lineor region ond wired os qn oscillotor with C46 providing positive feedbock.
The oscilloioris disobledwhen ihe AFC is switchedON.
15.
Binory Counter
up/down binory counter, consisting
When the AFC is ON o l2-bit synchronous
ol ML22, ML23 ond ML24, is incrementedoi ihe error frequencyrote, up or
down, occordingto the sign indicotion. The error frequency is opplied to the monosioble
to on error frequencyof lessthon.l '4 Hz
input MLl5 pin 4 where pulsescorresponding
ore inhibited; if ihe error frequencyexceedsI .4 Hz ihe pulsesore opplied to the counier
input. R88ond C53 deloy the clock slightlyso thot the counferis not clockedot ihe
16.
t/-J
RA. 1778Mointenonce
sometime os ihe up^own doto chonges, The ien mostsignificonidigits ore opplied io
the D-A converter.
17,
When ihe AFC is OFF the counleris clockedfrom the 2 kHz oscillotorond the
up/down informstion is token from the comporoiorMLl0d, which comporesrne
voltoge outpui from fhe D-A converierwith the voroctor voltoge of ihe 7 MHz phose
lockedoscillotor. This cousesthe counterto be held in sucho stote thot when the AFC
is switchedON ond the D-A convertertokescontrol of the vorociorline, the initiol
frequencyof the VCO is sufficientlycloseto 7 MHz thot fhe signol is held within the
possbond
of the corrierfilter.
Digitol -io-AnologueConverter
18.
ML2l is o l0-bit multiplyingd igitol-to-onologueconverter. The output current
is proporlionolto the multiplyingfrociion, k, which is determinedby the logic
inputfromthe binory counter, ond io fhe voltoge oppliedto pin 15, the V ref terminol.
The converter includes on internol feedbockresisiorto which the outpui of MLl6b is
connecied. A proportionof lhe ouiput is fed bock io the V ref terminol by MLl6c. The
combinedeffect of the feedbock orrqngemenlsis to produceo non-lineor relotionship
betweenk ond the output volloge which compensotes
for ihe non-lineor relotionship
between control voltoge ond frequencyin the VCO ond hence enhoncesthe frequency
occurocy of the AFC system.
Tuninglndicotor
19,
MonostobleMLl5b produces6 ms pulsesot the error frequencyrote ond ihese ore
fed io the front ponel meter, The meter performso mechonicoliniegrotion of the
pulsesond gives on opporently consionideflection proporiionolto the error frequency,
\{hen the AFC is switched ON, the meter is switched over to the voroctor control line,
Control Monosioble
20.
MonostobleMLl5o receivesclock pulsesfrom fhe digitol mixer ond produces
700 ms pulsesot the error rote. The Q output of the monostobleis connectedto
the Enobleterminolof the counterchoin, which is ollowed to countonly if the monostoble remoinsset. Thus, if the pulsesore greoter thon 700 ms oport, the counterswill
noi be incremenied;therefore no AFC signol is producedfor on error frequency, of less
thqn I,4 Hz. This creoteso 'deod-bqnd'which preventsthe AFC circuit from oscillotinq
oround the sel frequency,
AFC Lock Lomp
21 .
The AFC lock lomp is driven by TRII from the tronsmission
gote ML8 pin 9. The
gote is switched by the outpui of ihe NAND gote ML9 pin 9, which
tronsmission
hos three inputsconneciedso ihot the AFC lomp will light only if the following
conditionsopply:
t7-4
RA, I778 Mointenonce
\!
(o) AFC is ON,
(b) Thesignol-to-noise
roiio is occeptoble.
(c) Theerrorfrequency
is lessthon 1.4 H2'
ON-OFF Switching
of on eorthsignoloi
or obsence
TheAFC is switchedoN or oFF by the presence
'onii-bounce'
circuitR63,C37ond
pin l3 of the boord. Thisis oppliedto the
whenthe AFCis switchedOFFor
therequiredcondiiions
MLl0c, thenroutedto produce
22.
oN.
When the AFC is switched OFF, cqrrier derived AGC io the moin receiver is
dumped. MLlTb is reset' so thot pin 6 of MLl2 is low ond clock pulsesfor the
'0' on MLl4 pin 12.
counierore token from the 2 kHz oscillotor, which is enobledby o
MLl3o is resel, so thot pin 2 of ML12 is low, ond up/down inforrnoiionis token from
MLl0d which is ollowedto funciion by turningoff TRl3. TRl2
the outpui of comporotor
is switched on, so thot the VCO vordctor line is suppliedfrom thc phosecomporotorond
loop filter only. MLlg pin l3 is high, enoblingresetpulsesfrom the phosecomporotor,
ond o'0'on pin 13 of MLll preventsMLl5o from being cleored. Tuningindicotorpulses
gotesof ML8.
ore switched to ihe meter by the tronsmission
23,
When the AFC is switched ON, corrier derived AGC is ollowed to pdssto ihe
moin receiver. The 'l' is removedfrom the resei pin of MLlTb ond is tronsferred
to pin l2 of MLl4, disoblingthe oscillotor, Clock pulsesfor the counierore ihen ioken
vio the controlmonosioble,fromthe mixer. TRl3 is switchedon, holding pin I of
MLl0d low, ond the 'l' is removedfrom pin l0 of MLl3o; this ollowsup/down informotion to be token from the mixer. TRl2 is switched off, ML20b is set ond ML20o is reset,
of lowing the D/A converteronly to supply the VCO voroctor line. The ironsmission
gotesof MLB switch the voroctor voltoge to the meter.
24.
Adiusiments
25,
to rhe AFC
74 to 76, for detoilsof odiustments
Referto Chopter23, porogrophs
boordPM664.
t7-5
RA. I 778 Mointenonce
SIGIIAL FOR
OEMODI'.ATOR
ANIENM SICNAL
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DOWNTO 'OFRECT IHE ERROR
CON'ROLLOOP
FunctionolDiogrom:AFCControtSystem
Fig.l7'1
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Loyout:I
Loyout:AFC BoordPM664
Fig.Il.2
FOR I]rV EMF lNlO
R x . A N TS. I G N A L
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ML 5 B
F A S T - D E C AS
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I F S I O N A LD I S A P P E A RASF, C
I N H I B I T EID
MMEDIATELY.
W H E NS I O N A R
L ETURNS,AFC
RE-IOCKSAF'IERABOUT70mS
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A G CT OI F I &
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A MP L I F | E R
OUTPUTBUFFER
WAVEFORMSHAP€R
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S I G N A LT O N O I S EO E T E C T O R
R45 SEI 50 THATAFC LOCK
L A M P F L I C k E R SA T 1 . 5 ! V
'FULL
E M F I N P U TO N
CARRIER'
IO MLtS
T O ML I 4
P t N S1 & 2
COMPARAiOR
F A S T _ D E C ASYL,O W _ A T T A C K ,
I F S I G N A LD I S A P P E A RA' F C
INHIBITED
IMMEDIAIELY.
W H E NS I G N A L
REIURNs,AFC
R E - L O C XASF I E RA B O U T
70mS
_l
,AGCTO IFI &
IF2 BOARDS
A FC Boord PM664
Circuit:
(SheetI )
Fi9.17.3
lMHz GENERAIoR
PHASECOMPARATO
i
ML I 9
tsvO
^-^Y
r0nI
lMlh lo
3 aM H z
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INPIJI.
LEADS
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THEO OUTPUT
GOES
I
HIoHORLOW
ETIHER
PRovtotNouP/Dowll
INFORMATION
IOTHECOUNTERS-
ll1uLlIPI-YINO
DIG
TOANAIOGUECO
!oa|( V REF-WHE
K VARIESBETWE
0&t-2ro0EPEN
ON CMOSINPUTS
INCREMENIEO
UPOR
COUNTERS
. OOWNATERROR
RAIE,
FREOUENCY
MLI2C
2 K H zC M O s
osc -LAT0R
c1t
l-AFC ON
MONOONLYALLOWS UP/
OOWNCOUNIERTO BE
ENABLEO IF PERIOO
BETWEENERRORPUT5E5
ar.AFcoN
MLIIB
----.:t
-t-
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-l
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AFC ON
WE
1.5/N OK
FROM
PULSESFOR
PROVIOES
I GEN€RATOR
PHASE COMPARATOR
W H E NA F CO NM L 2 O 1
8 5s E I
ML2OA
IS RESET.RESU
1T
5T
I H A I M T 2 OP I N 1 2I S H E L D
Low, & MU6 TOSES
CONTROL
OF THE VARACTOR
VOTTAGE
W H E NA F CI S O F FM
,I
THED/A ]
COMPARES
VOLTAOE
WIiH IHE V
v o L r a o E , aP R o v t o E
INFO-FORTHE COUN
THI5 CONOITION
THE1
A R E C L O C K EB
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THIS CONDII]ON
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N B R A C X E TASP P L YW H E N
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ER
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Circuit:
A FC Boord PM66/,
(Sheet2 )
Fig.17.t,
g=r]=al!!B=='=9
9=A=B!- =f =rd'9i=e
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CONTENTS
INTRODUCTION
Mixer
Lryslo | (rscllloTor
L i m i i i n gA m p l i f i e r
u r s c lrmt n o r o r
DifferentiolArnplif ier
ond Switch
DiversitySignolComporotor
F S K l n h i b i tS w i t c h
Normol/ReveneSwitch
Adi,rstments
Poge
l8-l
l8-l
t 8-l
l8-l
l8-l
lB-2
l8-2
l8-3
l8-4
l8-4
ILLUSTRATIONS
Fig.No.
cs
DiscriminotorChorocteristi
ond Switch
Timing Diogrom: DiversitySignolComporotor
PM36B
boord
Demodulotor
Lovout: FSK
boordPM368
Circuit: FSKDemodulotor
RA. 1778Mointenonce
18.1
18.2
lB.3
18.4
ChopierI B
Contents(i)
\
)
i
CHAPTER
I8
9--8=
!: L4 I =9=t=9==o=
43 P==! =ry1-3=
4 I =q=
I I 5==g=E=
INTRODUCTION
boordis given ot the end of ihis Chopier'
A circuit diogromof the demodulotor
F i g u r e1 8 . 4'
l.
Mixer
.l,4
17: fromihe
f
MHz lF outputsignol (+ the FSKshift) ot bood pins 8 :i.d
The
The second
'
MLI
moin lFrlAFboord, i, oppiiua uG o bondpossfilter to o mixer'
input to the mixer is derivedfrom o crystoloscillotor'
2.
CrysiolOscillotor
3,
TM ond ossocioted
A i398 kHz crysioloscillotor(Cloppcircuit) is formedby TRI'
'
by
C17
components'Fine iuning to l39B kHz +l Hz is ochieved
L i m i t i n gA m p l i f i e r
4.ThedifferenceoutputfromthemixerMLl(2kHz+Df,where2Dfisequo|tothe
of ML2' ML3 ond ossocioted
FSKshift) is fed io o limiting omplifierconsisting
signol' which is fed
ihe output from the liititing omplifieris o squorewove
"orpon"nir.
to the discriminotor.
Discriminotor
E
ThediscriminotorconsistsoftwobondpossfiIterswiththeirossocioiedrectifier
of the two filters ore given in the
omplifier' The chorocteristics
ond o summing
following diogrom'
MIEEE
F i g . 1 18
'lB-l
RA. l77B Mointenonce
6.
As one input of ihe summingomplifierinverts,one filier chorocteristicis inverted;
summingihe filier outpuisin this woy mokesup ihe chorocieristic,S, curve of on
discriminotor.
FSK
Thus, if ihe tone is obove2 k1z, FL2 hc the higheroutput of the two
filters.
DifferentiolAmplifier
7,
ML8 ond ossocioiedcomponents
form o differentiolomplifier. To bolonceine
inputs, R45 is insertedinto the signol line from ML7, ond is set suchthot with o
I '4 MHz inpui (no shift), the inputsto ML8 ore of moximumomplitudewithout the ourput
of MLB switching. The output from MLB is compored,in MLI o, wiih rhe referencevolroge
(osset by zener Dl). The pulseouipui from MLIO is clompedto betweenOV ond 5V
opproximoielyby zener diode D7 beforebeing oppliedos rhe FSKoutput oi boordpins 6
ond 19, ond to the diversiiysignol comporotor
ond switcn.
DiversitySignol Comporotor
ond Switch
Note:
B.
For the purposes
of this description,the rporentrreceiver is ihe receiver
which contoinsthe FSK circuitsunderdiscussion.
This circuit consists
of schmittNAND gotesG2 andG7 , NAND goresG l, G3
G 4 , G 5 , G 6 , G 8 , G 9 o n dG l 0 o n d J K f l i p - f l o p M L l 3 .
9.
Accordingto the stoteof the ouiput from the AGC comporotorML9, ihe FSKsignol
from either the porent (moinchonnel)receiveror the second(diversity)receiver
.
(FSKlN) is routedto ihe output (of G9), BothFSKsignolsore phosecompored,ond
switchingwill not occur until either one odoptsthe somelogicol stote os ihe other,
10,
The AGC comporotorconsistsof o differentiolomplifier, ML9, which is useoro
comporethe diversityAGC input voltogewith o voltogederivedfrom the moin
chonnelAGC voltoge. The output from ML9 is oi logic 'l' when the + input is more
positivethon ihe - inpui.
II,
The functionof the JK flip-flop MLl3 is os follows:Stote before CK edge
Stote ofter CK edge
JK
0
0
0
I
I
0
1
I
I
\JN
\rin
Qn is the outputstote beforethe clock edge J ond K ore definedin Figure 18,2,
l8-2
RA. 1778 Moinienonce
comporotor-ond
A timing diogromto showihe operoiionof the diversitysignol
showexompleFSKsignol
switch is shownin FigurelB,l , The iop of two woveforms
con be seenthot the signols'
outputsfrom ihe porent,"""',-u",ond the seconi receiver' lt
olthoughthe some,ore out-of-phosewith eoch other'
12,
(input to MLB/iT/K2) k
Up io point A, ihe outputfrom the AGC comporotor
porentreceiveris
opproximotelyOV, indicotingthot the AGC.voltogefrom the
olreodyswiichedihe
*or" poririu" ihon thot from the secJndreceiver' The circuii hos
(shownos the inverseof the
FSKouiputof the porentreceiverto the outputof the switch
the Q
The conditionof the J ond K inpuisto flip-flop MLl3 couses
rsr i"plt at Gg/ll).
is clocked' The clock
O'"rtprtt f-n,, tt'tLlgto remoinunchongedwhen the flip-flop
signol; for the
FSK
""J
to
the
prlr", or"'not shownos ihey occur ot o high speedreloiive
os soonc6 the input conditions
operotion
irrp*", of the timing diogrom,flip-flop
,occurs output from NAND gote GI0
ihe
!r"'"hong.d. The O outiri is ot iogi""O', which holds
;l ', irrespeciiveof the condiiionsof its secondinput' The Q output is ot logic
ot logic
'l' wiich enoblesNAND gote GB io oct os on invertorfor the signol oppeoringon its
the porentreceiver'
secondinput; this secondinput is derivedfrom ihe FSKsignol from
'l', NAND goie G9 octs os on inverterto the input from
As the oripri from G8 is ot iogic
the porentreceiver'
CtO. fn" output from G9 is ihus the someos ihe FSKsignol from
13.
|4.AlPoiniA,iheAGCIeve|chongestoindicotethotthesecondreceiveriscorrying
ond ot
the strongerFSK signol. The co,idition of the J ond K inputs is chonged'
inhibiting.thefSK.signolflow
the nexi clock pulse, the 6 outputgoesto logic'0', thereby
'l'
to enoblethe FSKsignolflow
fromthe porentreceiver, ond ihe Q-outputgoiesto logic
lhe secondreceiver'
fromihe secondreceiver. The output Oilll is ihe FSKsignol from
"t
.l5.
corrying
At poini B, ihe AGC level chongesto indicotethot the poreni receiver-is
is outreceiver
the
porent
the strongerFSKsignol. However,ihe FSKsignol from
flip-flop ore orronged
of-phose*i,i,,t,i, from thJsecondreceiver. The inputsto the JK
os ot point Bl '
in-phose,
sucirthot lhe outputswill not switchuntil the FSKsignolsore
onreceiptofthenextcIockpuIse,theFSKsignoIfromtheporentreceiverisswitched
to the outPul'
l6,TheoperotionotPointsCondClissimilortothototpointsBondBl'thedifference
from ihe porent
uuing'thotot B/Bi, swirchingdid nor occur until the F5K signol
from the secondreceiver)'
receivergoii"a o logic'l;siote (to;gree with the FSK signol
F S KI n h i b i rS w i i c h
lT.TheFSKsigno|isclockedthroughtheD-typef|ip-f|opMLl6whi|ethepreset(PR)
'l ' (FiK norroi o,.revene positionoi ihe receiverMODE switch
infrt is ot iogi"
'0' (0V) is oppliedto boordpin l0)' For the.remoining
hosbeenselectedond o logic
'0' oi pin l0 is removedond the tliP-f loP rs
oositionsof the MODE switch, the logic
'l').
presef(Q ouiPuigoesto logic
Note:
frequency'. The clock frequencyis very high compcredto the FSKsignol
of MLl6'
output
ond
input
the
thusthere is only o'smolltime-deloybeiween
I B-3
RA, l77B Moinienonce
N o.rmol/Reverse
Switch
lB.
The FSKsignol ond its inverseoppeoroi the ouiput of MLl6 (Q ond Q respectively) . Accordingio the level oi the input of NAND gote GI3 (wiredos on
inverter),eiiher the FSKsignolor its inverseore routedthroughto MLl8, o reloy driver.
The input to G13 (eorthto reverse)is ot logic '0'when the FSKreversepositionon the
receiverMODE switch hosbeenselected,ond oi logic 'l' for other modes,
When boordpin I I (eorthio reverse)is ot logic '0' the output from Gl3 is ot
logic 'l' cousingNAND gote Gl4 to oct os on inverterto the F5K signol from
M L l 6 . T h eo u t p u tf r o mN A N D g o i e G l 5 i s h e l d o t l o g i c ' l ' b y t h e l o g i c ' 0 ' i n p u t ,
therefore,NAND gote GI6 octs os on inverterto the ouipui fromG l4. Whenbooro
p i n 1 l i s o t l o g i c ' l ' t h e o u t p u tf r o mG l 4 i s h e l d o t l o g i c ' l ' o n d G l 5 o c t so s o n i n v e r t e r
to the invertedFSKsignol from MLl6.
19.
20.
The FSKsignol from the normol/reverse
switch feedso comporotor
with its threshold
'lr
'0'
-ll) output
midwoy
between
(+12V,
set
ond
levels. This provideso polor
to drive ihe relov,
Adiusiments
21 ,
Referfo Chopter23, porogrophs
77-79, for deioils of odiustments
to the FSK boord
PM368.
r8-4
RA. l77B Mointenonce
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TimingDiogrom
Diversity
SignotComporotor
ondSwitch
Fig.18.2
Loyout: FSK Boord PM368
a
bo l 9 o
6
I
20
13
l6
cc
t5
l4
t0
DA 42016
PM 368/I
i Boqrd PM358
Fig.l8.3
llv.*EF+z rvlosv
OUTPU1 SHOL]LDAE A SOI]ARE
I/llAVEAT THE OIFFER€NCE
FREOUENCY
OF TI1E SIGNAL,
IHE EEO, LEVEL IS
rHE ?lf__Esf
D
0t
ACTIVE
1 4 0 0 H 2B A N DP A S SF I L T E
IF AGCOF THISRECEIVER
IS
-0 6VlEG
o{ITPUI tS APPROX
BIJTIF OIVAGC{FROMOIHER
+ l7V (EG
H|GHER,
OlrTPUr
EE'g
oIGi;l
ItoH-o45IEaA
FTEET-6T------
1 . 3 9 8K H zC R Y S I A LO S C I L L A 1 O R
IBEO)
A C I I V E 2 6 0 0 H 2 B A N D P A S SF I L T E R
L]MITINO L.FAMPLIFlER
FULL_WAVE
RECTIFIER
S U M M I N GA I V P L I F ] E R
AOTH CIRCUIIS HAVE UNIIY
I I N V E R T I N GGI A I N 5 0 1 H A I
0c ouPurs aRE- 2.rv
. +zrv1osv
WHENlHE OJTPI}IOFML8 ISTVE
wRl. 2 tvREE, lHE OTTPUItS+1.7V
WHEN-v., IHE oUIPUIIs APPROX
_O'6U IHEsE L,EVELs
AREgJIIABLE
], LEVEL TS
RECTIF]ER
FULL.WAVE
A C T M 1 4 0 0 H 2B A N DP A S SF I L T E R
R3'N
I
TRANSTSIoRS
rRl BFxrs
I rR2 2N236e
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I
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r-llt-
t -"^
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rRt\
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R36
IF AT ANY IIM€,IHE OUIPUT OF ONE FILIEA
I5 LARGER THAN THE OTHEq'I!E 0c OUTPIJT
OF TI]E APPFOPRIATERECIIFIER WILL BE
LO\A/ER
IO.]E rc TNVER'ING NATUR€ Of THE
CIRCU'T ). WHEN THIS HAPPENS IHE
AALANCE OF IHE 5UMMIN6 AI.IPLIFIER 15
(IPSET ANO 11 PROOUCEs AN OUTPIT
WHICH IS NOT 2.IV REFERENCE
E
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l 3 9 8 k H zC R Y S I A LO S C I I L A T O R{ B F O )
C i r c u i t :F S K D e m o d u l o t oPr
gJMMING ATviPLIFIER
F U L L - W A V ER E C T I F I E R
C H A N G E -O V E R ] I M I N G
AO]UsIMEN1 OF R(5,sEI INPUI FREO1I€NCY IO BOARO
I0 1 .00 00MH2.coNNEcl 20xn/v
MEIER ON 50,4 RANGE EEIW€EN
PjNS 3,2 OF MLro AOITST FOR ZERO
WHEN THE OITPI'T OFMLS 15+VE
v(Rt zrvREE, rHE CirTPUl tS+rrv.
WHEN -Vc,IHE oUTFITTlS APPROX
_0,6V. THESE LEVEL5 ARE gJIIABLE
FULL-WAVE
RECIIFIER
IF AT ANY IIME,]HE OUTPUI OF ONE FILTER
IS LARGER THAN THE OTHER HE DC OUIPUI
OF IHE APPROFRIATERECTIFIER WILL BE
LOWERiOUE IO INVERTINGNATUfII OF IHE
CIRCIIIT i WHEN IHIS I]APPENS THE
BALANCE OF IHE SUMMING AMPLIFIER 15
LJPSEI ANO IT PROOIICES AN OUTPUI
WHICH 15 NOI Z 1V REFERENCE.
T R A NS I S T O R S
I N T E G R A T ECDI R C U I I S
--:::
otoDEs
I
I:: I
€
M L Tl
@
1f: I
ML9
MLIOJ
^-t
DI I
osl
ML12
MLB l
M L r aI
i r L r sl
MLI6
r > 2rv
.l
r-l
'3tF
I'u
_._o!!_
C i r c u i :t F S K D e m o d u l o t oPr M3 6 8
"i f"
-.-lL-
t
- -
.Fq_qlg! trr_quq4g lEql.q C H A N G E - O V ETRI M I N GC I R C U : T
CHANGE-OVER
sglle!
FSKNORMAL/REVERSE
OUTPUT
AMPIIFIER
su]gE
cLosEoc{rE t5 oGIc
I} WHENAOIH sICNAs AR€
AT TIIE SAMELEVEL.
2I ON THE POsITIV€ED6E
OUTPUIs'IAIE DEPENOS
ON ACC COMPARAIOR
INVBIINGl$PUi tS S'ASEO
g€lw€€N lrL L€vE6.
WHENINPIJI15LO6IC'I
WHENtNPu',t
l5 |'oclc 0
tf NoRMAf15s€lEcrEo,
o SIGNA l9 PASS€OrO
IF'R€V€RsE'I5SELECIEo
o SIGNALrs PA55€0 10
03
o9
FSK
Fig.l8.4
g=rl4tIl=B=='=?
l=Q=ry=EE==s=_!=8=?L=r=E=9=Jr=N9=L!=9_LN9=
=3=9=A=89==!=ry1=3=/=g=A=N
CONTENTS
Poge
INTRODUCTION
tv-l
MAIN POWER
SUPPLIES
S u p p l yI n p u tF i l t e r
RegulotorBoordPM370
-ll Regulotor
+5V Reguloior
+l2V Reguloior
+20V Regulotor
TelegrophSupply
l7-l
l9-l
l9-l
l9-l
t9-2
t 7-J
I Y-J
I y-J
AF AND MEMORYREGULATOR
BOARDps427l
+14. 5V Regul oior
MemorySupply
ADJUSTMENTS
l9-3
l9-3
t9-4
l9-4
ILLUSTRATIONS
Fig.No.
E q u i v o l e nCt i r c u i t : V o l t o g eR e g u l o t olrC
Loyout: RegulotorBoordPM370
Circuit: PowerSupplies
Loyout: AF ond Memory Regulotor&,ord p5427/l
Circuit: AF ond MemoryRegulotorBoordp5427/l
PowerSupplyDistributionDiogrom:RA, l77B
19.I
19.2
r9 . 3
19.4
lq
{
r9 . 6
ChopterI9
RA, 1778 Mointenonce
Contents(i)
AP 116E-0754_68
CHAPTER
POHER
"
2'
19
S| 2U P P L T E -s - . . (] N q L U D I '7N G
PM37O
ND
I
' | | | = . . . 2 "- t : -- -- z- 2 | P
z ' . |92. 4 - I . p . | . ' -- i t ; z -: = a A
a' .t = = .
"
Ps\27/1\
: =. 2. | . = . . 2. | =
INTNODUCTION
1'
The powensuppry section of the recelver conprises a supply input flr'er,
voltage
selector unit, nains transformer '1T1, regulator UoarO pll37b .ni
th"""
power transistors mounted on a heabsink atLached to
"e"i""_pui"
the rear panel 0f the receiver.
stabilised supplies sf -7y r +5\ t +12y and +2ov are provided togerher
wiLh an gO-o-gov
teLegraph supply. Additional circuiLry, nounbed on the AF and;e6ory
board (para. 10)
contains a +14.5V regulator for the audio ampllfj.ers, and a +5V rnernoiy
supply. The
> smoothing capacitors, 1cra, rcrb, 1cza, jczb, and 1ci to
1c6,
Inorrit"d
on the inside of.
the rear panel, power supply distributlon 1i shown in Figur; "r"
19.6.
MAIN POWER
SUPPLIES
Supply Input Filter
2'
The supply inpubr at lPL1, ie fed via a suppty fuse,
lFS3, and a doubre pole 0N/OFT
swltch, go the suppty input. filier,
1L1, 1L? and capacitors Clg to CZ1. the
flltered
' l v s 1 . outpu! I's connected to the mains transforner, 1T1, via the voltage seLector unlt
This utilises four identical integrated circuit regulaLors, ML1 to
ML4. This device
consists of a lenperature compensaLedreference anpllfler,
error
anprifter,
serles
pass transisLor and currenb rlnit circuitry.
An equivalen! circult of the device ls given
1n Figure 19.1.
3'
4'
The error anpLifier is used lo compare the reference voltage (maxinum
approxinately
+7V)
wibh a saxopleof Lhe final stabilised outpuL vollage ivla a polential
divider
f Sreater than the refenence voltage) and the output of the Jruor
anptirier is bhen used
Lo conlrol the serles Pass transislor.
This transistor is also contr;lled by a current
limiting sbage which itserf rs controrred by the current drawn fron Lhe suppry
by the
exlennal circuitry.
-7V Regulalor
5'
A 10'5v secondary winding of 1T1 is connecled to a full r"ravebridge rectifier
D1,
via board pins 4! and 50 and rink LK1. The positive output rron D'r ls
apprred to
the collector of Lhe exbernar geries pass transistor, lTRr, via board pln
r, whereas the
emitter of lrRl is returned to the negative output of o1 via pin 4, B2i
and Rl4. The
posltive supply voltage for ML1 (v+) and arso Lhe corlector
vortage (vc) for the inbernal
nA. 1778 l{aintenance
AndL 7 April 89
19-1
ERECJEI!C V
COMPENSA]EO
Z€NER
'
VOLlAOE
REFEREN'E
CIJRRENI CUiAENI
sENsE
L[,]t
E q u i v o l e nCt i r c u i t ; V o l t o g eR e g u l o t olrC
Fig.l9. I
seriesposstronsislorore token from the +12 regulotedsupply. The output from the reference
omplifier (v REF)is oppliedvio Rl ro the non-invertinginput of the error omplifierwhilst
the inverting input is connectedto the -7V regulotedoutpul vio o potentioldivider Rl3,
R9, presetvoltoge odiustpotentiometerRB, ond R7' Currentfoldbockis providedby Rl4,
R 2 l, I R l 2 o n d I R l 4.
+5V Regulotor
lTl vio
Bridgerectifier D2 is fed from o l0'5V secondorywindingof tronsformer
boordpins45 ond 46 ond link LK6. The positiveoutpulfrom D2 is oppliedto the
collectorsof the two seriesposstronsisfors,TRI ond lTR2. The positivesupplyvoltoge for
ML2 (V+) ond olso the collectorvoltoge (VC) of the internolseriesposstronsistorore token
6.
t9-2
RA. 1778Mointenonce
from the +20V regulotedsupply. The referencevolioge reveroppriedto the
non-inverting
input o-fthe.erroromplifier is presetby the potentiometer,R3, ond the invertinginput
is
toke_n
from the 5v ouipurvio Rl5, currenr foldbockis providedby Rl6, nz2, inl3
ono
lRl5.
+l2V Regulotor
7.
Thissupplyis derivedfrom o 16,5V secondory
winding of tronsformerrTr . The
positiveouiput from the bridgerectifier, D3, is oppliedto the collectorsof the
two
seriespossironsistors,TR2ond 1TR3,whereosthe positivesupplyvoltoge for ML3
ond the
collector voltoge for the internol seriespcrsstronsistorore token'from th1 +20V reguloted
supply. The referencevolioge is opplied vio R5 io the non-invertinginput of thJerror
omplifierwhilst potentiometer
Rl7 presetsrhe voltogelevel oppliedio iire invertinginput,
The reguloted+l2V output is token io boordpins 16, lz ond iti, ond to ihe ou"n oi rn"
frequencystondordvio R32, D6 ond pin 20. current fordbockis providedby RlB,
R24
ondI Rl6.
+20V Reguloior
8.
Thisstoge, which is similorto the +r2V regulotor,is fed from o 23V secondorv
windingof lTl ond bridge reciifier D4. The reguroiedoutput is presefby potentiometer Rl9. Currentfoldbock is providedby R12, R2O,R2gond R34.
TelegrophSupply
o
The8O-0-80Vtelegrophsupplyis providedby o centre-ioppedsecondingwinding
of lTl ondo full wovebridgerectifier,D5. Smoothingis providedby lRl0, lC5
lR9, tC6.
Fis.19.5
10.
Thisboordcontoinstwo circuits, A regulotorcircuit provideso +14,5V supplyfor
the moin IF/AF botd ond orsofor rhe rsB lF/At bo'd, where f ited. The 5v
memorysupplycircuit relies for its operotionon on exiernollyderived+l2v supply.
lh
purposeis to mointoin the +5V.supply to ihe disploy boord ond so prevent lo*
oi fregr"n"y
setting informoiion
os would otherwiseoccur followingo po*e. foilrre.
+4. 5V Regulotor
I l,
This consists
of o three-terminolpositivevoltogeregulotor, Ml2, togetherwith o
buffer omplifier, MLl, ond o presetoutput level odiusfpotentiometei,R3. rt is fed
from on unreguloted23V supply from fhe powersupply reguloior boord PM3ZO.
I Y-5
RA. l77B Mointenonce
MemorySupply
An unregulotedl4V supplyfromthe regulotorboordPM370is opplied io boord
pin 9, whilst the +l2V frequencystondordoven supplyis opplied to boordpin B.
The oven supply(seeFigure19.3) is token fromihe reguloted+l2V supplyvio o resistotr
ond o diode (R32,D6) or, in the event of o powerfoilure, from on externol+l2V supply
(conneciedto the reor ponel STD/+l2V terminol)vio two seriesconnecieddiodes
(D7, D8).
12.
.l3.
The unregulotedl4V supplyot boordpin 9 is routedby diode D2 to o threshold
terminol+5V regulofor,ML3, ond olso io the boseof TRI vio potentioldivider R5,
TR2ond TR3to isoloteihe
R6. TRI is turnedon ond thusholdsoffthe regulotortronsistors
+l2V supply.
foil, ihe 14V supplyot boord
Shouldthe moin sourceof o.c. powersubseguently
+l2V
pin 9 is removed,TRI is turnedoff ond the
oven supplyis routedvio TR2
ond Dl io the +5V regulotor,ML3,
14,
'
ADJUSTMENTS
'15,
Referto Chopter 23, porogrophsl0 to 12, for detoils of odiustmentsto the Power
S u p pile s ,
t9-4
RA. l77B Mointenonce
ffib.2725262423221817
wp"F.ryfg'sry
ffi
#.qhkffi
fl-*#ffi,#
Loyout: Regutotor
Bocrd pM.3Z0
Fig.19.2
IHE -?VOLT REGULATORIS SIMILAR IP TH!
OTHERS EICEPT IIIAT THE POSI]IVEOUTPUT
TO RECEIVEROV LINE.
IS CONNECTEO
LEAVINGTHE NEGATIVELINE AS TIIE -7V
OUTPUI
I
[-
1,,
TRANSISTORS
TRI TR2 NOI FITTED
RCA40412
TR3
lTRl,lTR2,lTR3 2N6055
'
DIODES
o1
02,03
o4
l . r L ,l B !
lClo
4?00
1.,Lrir^
100B0sA
5SEl05
MOA20t
lsa20
1 00 r
OA9I
D5
86,D7,D8
D9
INTEORAIEDCIRCUJTS
MLl.ML2,ML3,
Ml4
|;;;\
f" tl
____
,rA723Ht't
I
TYPrcaLoc voLTAcE I
As MEASURED
w|lH
I
2oKn/voLTMErER. I
aSserrrrcr I
t vnrr,rs
___l
trl
[J
lPLI
L I NE
l 0 0 v- r 2 5 v
EARTH
OR
?00v-250v
45-651"i2
NEUTRAL
le
lN
SUPPLYJNPUTFILTER
RP983
NOIES:
r. COMFIN€NTSFREFIXED1 ARE NOT
MOUNTEOON THE AOARD.
2. !(I
4b
gt ttaL
T O L K 5 A R E F U S I S L EL I N K S
3, -?V OUTPIJTDEPENDENION +12V OUTPUT
+IzV, +5V OUTPUTSOEPENOENION +20'
OU'IPUT.
MqJNTEO
ITHESE COMPONENTS
ON IHE CHASSIS)
WE
woH 9318 D C 4
6.3
1t2
t4t5
w o f l 9 3 r 8 l D C 4 a 9 66 l9
5
2t2
i-,
-? REGULAIOR
+12V PRE-
|NPUI
20V PRE-REGULATEO
...._-------------,rl--.-.r
l"':9
,..
C1JRREMtlMlT OPERATES
7.15't I $IHFN VOLTAGEON plll 10
le l' . ft{jl
i."l''lT;l'fffJlicJ^ETE"
-------r
,20 021
,21
031
011
R32
t.7
SEMI
REGUL
92A
99
/OLTAGE
SELECTOR
UNIT
(REAR PANELI
DIOOE
ENSU
FEOII
RECE
STAN
1C4i4?00
|
".
L?tJ
itt L-
c1
170
MOIJNTEO
{IHESE COMPONENTS
+85v
REGULATORBOARO PM
Circuit,Power
Su
i
-"
aPn6E-0754-68
April89 lAmdt7)
--l
I
I
-7 REGULATOR
+r2v pRE REGULATED
rNpuT
0 v L I N El s
OUTPUT
REGUIATEO
OIOD€PREVENIS
-7V LIN€GQING
+V.
+5V REGULAIOR
+?OV PRE -REGULAIED INPUT
II
I
i
i5V OUTPUT
I
20V PRE-RECULATEDINPUf
---------------'
;;.;l
l^
l^
;:;l
, -----l!---lJ-"
-./ ? l5v I
!0 5v1
^\ --r
/
lI
CVRRFNI LIMITOPERATES
WHEN VoLIAGE ON PIN 10
rs 6sonv (aPPRoxI GREAI ER
IHAN VOLTAGEON PrN t.
I
t'
*trt
1 .,ru
(oRANG€r
I
+I2V OVENSUPPLY
IO FREOUENCY
IAND
STANOARO
MEIIORY REGU'
ARE
IR12-IR16
LIMITIN6
CURRENT
STANOBY12VINPUT RESISTORS
MOUNTEO
ON REAR PANEL
T E R M I N A Ls ' R I P I .
HEATSINK
tREo)ij tI .
IrzovouTPUr
'r[r
o vr r r e
ry,, :- I .,
qNt'i,
+80v
+85V
TELEGRAPH EARTH
REOULATOR
Y1"_r."tI-l
Supplies
Circuit'Power
Fig.l9.3
Loyout:AF ond MemoryBoord
PS[27t1
Fig.19.4
[;;.;_l
| fi1inr-- eoos
I
TR2
BFX39
I
|
s!99ES
or,D2
t0o1
INTEGRATED
CIRCUITS
MLI
L""_*
I
tttt'i_i
|AZIC
MEMoRy
suprly clRcutT
Li:*"'*'"'":"'
lr*'
L-
@
l w o H m a g l B c a S r ? 2 /Iv
FLFf---------l
HEArstNx
Circuit:
A.FondMemory
Regulotor
BoordPSt 2711
Fig.19'5
POWER
SUPPLY
ANO
REGIJLATOR
BO4AO_Pf,|370
,:- -:\
.o'\
ns{
9,
"e"
$
f$$
*"].s*P"
are
..-.r-..-.--r---
f" ."'
ll
ll
A-EI I{EHORY
REG{'LATORAOARD
PSa2ltl
rl
R F U N I T- -
FIRST ||IXER
AOARO PM335
FIRST IF ANO
sEcoNot txER
BOARO
Pit336
aoaRoFr{364
IS8/LSB tF|AF - _
aoaRo Plt36a
AFC AOARO
PU369
I'IETERSWITCHING
maRD P[419
-
FSK AOARO
PM360
FREOUENCY
STaNDARD
31}'IH: G€NERAIOR
AOAROPN339
LF L@P AOAROPM568
-
UPPERLOOFEOARO
PM589
TRANSFER
L@P
BOARDPS338
HF LOOPBOARD
DECOD€RSOARD
PLl594
ESPLAY AOARD
P 692--
MEMORYBOARO -
@
lToHTorr-l
-
PowerSupplyDistribution
Diogrom
RAIZZ8
Fig.l9.6
CHAPTER
2O
_c_I_r-Q-N_!A N _D_
__c_
H_A-s_
s_r_s_
__L_a_y_o_u
I N j=E8=9gt_\_N_q
-r
( =!=9! =u=
?=r=N=-G=
=9=g=4
& q==q4 l=l tl
CONTENTS
Poge
METER
SWITCHING
BOARDPM4I9
20-l
INTERCONNECTIONS
CHASSIS
LAYOUT
20-2
ILLUSTRATIONS
Fig. No.
. Loyout: Meter SwitchingBoordPM4l9
Circuit: Meter SwiichingBoordPM4l9
Loyoui: Front Ponel
Loyout: ReorPonel
ReceiverLoyout: PlonView
ReceiverLoyoui: Underside
View
Interconnection
Diogrom: RA. l77B
RA, l77B Moinienonce
2 0 .1
20.2
tn',
20.4
,AA
20.6
20.7
Chopter20
(i)
Confents
i
LNATIEK
ZU
q I =r=9=
I N J=E&9=Q=N=N=E
Dr=
! ==AN 2 =EX A 5'! ! 5==LA y=9=!=r
(r=N=q=L
y=p=r=
N 9==!=o:Aeq_=! J44I I
METER
SWITCHING
BOARDPM4I9
I
2.
A double-pole,ten-woy switch, SA, connecisthe front ponel meter, Ml
, to vorious
meteringpointswithin ihe receiver, vio the meier boordcircuitry, cr follows:(l)
Positionl: TuneCorrier
Thismeetingfocility is usedin coniunctionwith the AFC swiich ond is,
iherefore, only opplicobleto versionsfilted with the AFC boord. \Men
the
AFC switch is set to OFF, the outputsignol from the corrier tuning indicoior
on the AFC boord is oppliedto the metervio boordpin 23, Rl2 ona SnZ.
This is o posiiive-goingpulsedsignolof o fixed pulsewidth wherethe pulse
repetifionrote is equol to the differencein frequency, For precisecorrier
iuning the receivertuning conirol is odiustedfor o mini.um meterreoding,
Whenthe AFC switch is ser ro either FLjLLCARRTER
or prLOTcARRTER,
the
meteris connectedto the vorociorline of the Z MHz VCO on the AFC boord
ond provideson indicoiionof the ovoilobleAFC hold ronge (AFC+ O -scole)
.
It moy be usedio determinewheihero slight odiustmentof the receiver
tuling is required(dueto o drift in the tronsmisiion
frequency)to mointoin
AFClock.
(2)
Position2: RF
Thisprovideson indicotionof the sirengthof the receivedsignol ond is
derived.fr-omthe AGC ouiput signol from the moin lF/AF Uoora
lSSareceivers)
or the differentiol AGC ourpur from the moin ond ISB IF/AF Uoora,
llSB
receivers), The AGC output signol from ihe moin lF/AF boord is oppli"d to
fhe boseof emitter followerTR2ond ihence io the metervio R4 ond Rr4.
For
lsB versionsthe AGC ourpursignor from rhe rsB |F/AF boord is oppried to the
boseof TRI ond the output is oppliedto the meter.
(3)
rost on J: L5B
The oudio line outputsignol from the ISB IF/AF boord (lSBversionsonly) is
oppliedto the metervio boordpins I I ond I2, R3 ond bridge rectifier D5
to D8.
20-l
RA, 1778Mointenonce
(4)
4: AMy'USB
Posiiion
The oudio line ouiputsignol from the moin IF/AF boord (which corries oll
modesgenerolly,bui noi LSBin ISBreceivers)is oppliedto the meter vio
boordpins l5 ond 16, R2 ond bridge rectifier, Dl to D4.
(s)
5 ; D R I V EL E V E L
Position
This provideson indicotionof the locol oscillotorouiput drive level opplied
to ihe first mixer. A preseivorioble resistoron the first mixer boordo l l o w s
'V' portionof t h e
to obtoin o meterindicotionwithin the
for odiustment
m e t e rs c o l e ,
(6)
The reguloied+20V, +l2V ond -7V outputsfrom the powersupplyregulotor
boordore oppliedto ihe meterswitch vio suitobledroppingresistorsto provide
'V' portionof the meterscole'
in eoch cose, o meier indicotionwithin the
INTERCONNECTIONS
Fi9.20.7
The connectionsbetweenboordsond from boordsto the ponel-mountedcontrols ond
indicoiorsore shownin ihe interconneciiondiogrom,Figvre20,7, which is lorgely
ore not included, theseore shownin
self-explonotory, Powersupplyconnections
C h o p t e r1 9 , F i g u r e1 9 , 6 .
3.
LSI is connectedfo the AF omplifiervio o iock socket
The front ponel loudspeoker
is ouiomoticolly
ore pluggedinto the sockeithe loudspeoker
JKI . lf heodphones
resistor
R3.
The loudvio
io
the
heodphones
the
signol
is
opplied
ond
AF
disconnected
to
switch
OFF.
SQ
by settingihe LS ON/OFF
speokermoy olsobe disconnected
4,
CHASSIS
LAYOUT
5.
The loyoutsof the front ond reor ponelsore shownin Figure20.3 ond 20.4. fhe
receiver chossislovout from oboveond below is shownin Figure20'5 ond 20.6'
RA. I778 Moinienonce
l
Loyout:MeterondSwitchingBoordpM4tg
Fi9.20.1
'
'-\
r-', )
APt16E-0754-6B
-l
FSKOIITPUT
FROMFSX
BOARO
+
LO DRIVE
FROMMIXER
II
I
roK
a
roK
-_l
[--t*on"tro.t
I t*t,trr ."r,
I I o_!99E!
I
i
|
Li::".
SWITCHSA
[""0a"
ro
"oo.
no.orr.,
I TUNECARRIER
2 RF
3 tsB
I A!t,/USA
5 ORIVELEVEL
5 + 20V
7 +t2V
I
+5V
IO FS|( OIJIPUI
FE:N'6TTEdiE5d5I
.lon.82 (Amdl.3)
Circuit:MeterSWitching
Boord
Ftg.20.2
_\,
.\
\l
t
Iilsllt
RA.1778
ililffi+t{ffi
RF II,}IE
-"\/
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((
w
PHONES
lw-orr3-El
))
"botfu
i*-u.(f
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isb-'rv
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IUNINGRATE
nrcdium itow
AGC
POWER
on
o
om/usb
O-lin
tv.t-O
,4.
ltb
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Loyout:FrontPonel
drtoaA
b"kV
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;f@
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POWER
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)
.4,
v
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d.itc t.v.t
+20
*r'orrftt+n
t'b.( (
.rl\\\
\\\r*'
) lt-t
l:*.$Hdo*o,o
o
AF GAIN
Fig.20.3
a\
I rrnr I
\J
Exr
|FFnn
5PARE
\
[ 'rnz I
\J
Uah l{-Olrl
i(9,
rNl
riltl
AT
i.
n)
\J
Loyout:Rcor PonetRA.l778
5q!
GF
500
o
I;)
e
\J
a\
\J
n
A
n
IJ
.r4
Y
o
-
t?tffil
t-l
tel
L:J
,**@
o
l!.l
E -c", **t
=,=EEiH:E
SPAiE
,ruL@
t rTR, I
a
r-"t
L:J
LJ
rt o
o
o
@Lo
o
lNroul
/A\
\v
TRA|rSII SCREW
EXIERI'|AI
coNlFot
S(rcXET
Rcqr Ponel RA.l778
Fig.20.t,
POWERSUPPLY
SMOOTHING
CAPACITORS
RF PROTECTION
FUSE
(500mA)
R F INPUT
CONNECTOR
RF BOARD
PM582
ls8 MAIN
IF/AF I F I A F
BOARD B O A R D
AFC
EOARD LOOP
P M6 6 4
lt r
ilt[
iltl
LF
LOOP
IIIIM
iltl
il|I
--T-r
t\-
r--------l
I-
|||1.---r-----.-1_
ll",
ll lffillr-
--J)
o
lllHl
| ,--r ll
tt
\ tl
BALITASI=-ff
LAMP IFSK}
/
BOARD
ftrwl
mHstt--l
,rori.*-.*
CINNECTOR
INPIJT
ltnli'#'t5fiili"tit$Ht
:TopViewRA.l778
ChqssisLoyout
/ lL-
POWERSUPPLY
IlHINGCAPACITORS
POWERSUPPLY
BOARO
IF
ILTER
OARO
PS367
LF
BOARO LOOP LOOP
P M6 5 1
PM588
MAINSTRANSFORMER
AF & + 5VIOISPLAY)
REGULATOR
BOARO
ASSEMBLY
CONTROL
&
MEMORY
BOARD
OPTION
S\{ITCHES
CONNECTOR
OUIPUT
FROMSECOND
MIXER
IC30(BELOWI
c3l
METERSWITCHING
BOARO
SHAFT EITICODER
TOlst tr
MEI,IORY
:TopViewR4.1778
Loyout
Fig.20.5
.ACCESS
TO MECHANICAI
DAMPINGSCREWFOR
KHz TUNINGCONTROI
fl.rsE PozloRlv scREwDRwERl
&Fnt
moFTdiEt
ChossisLoyout: Underside
View RAl77g
Fig.20.6
srowI
MEoIuM
}IUNERATE !
J
I
FA5T I
CONTROL AND MEMORY SOARD
+5VD
Rl!
210
(PART oFl
OISPLAY
ELANX
pwR.F
REAO/WR.
":*"f*
^,^,
{l-:::+=-"5:
LOCAL CONTROI"
TUNE RATE
Cl']ANNEI.
5ElECT
INPUTS
REYERTIVE
CHAI'IIIEL
NUMEER
OUT
EXI, CONI FRONT PANEL TUNE ENABLE
ciocK
SWEEPTUNESELECT
EXT UPIOOWN
RECEIVEB
SELECT
A F CO N / O F F
A F CF U L L / P I L O T
ANTENNA
1239
338
137
735
E36
932
t0
lr
1?
t3
11
15
!6
t7
tE
t9
20
2t
22
23
21
25
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28
29
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3239
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32 33
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32 35
32 36
30
30 39
30 30
30 37
30 33
30 31
30 35
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31 39
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31 33
31 34
3! 35
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APl15E-0751-68
Jon A7 | Alndt 5 |
MEMORYBOARO
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LINEOUT
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Interconnection
Dogrom: RA.f778
Chossis Fi9.20.7
CHAPTER
DISMANTLING
AND
2I
RE-ASSEMBLY
CONTENTS
Poge
INTRODUCIION
I N I T I A LP R O C E D U R E
RFBOARD
- MAIN COMPARTMENT
PRINTED
CIRCUITBOARDS
P R I N T ECDI R C U I B
I O A R D-SM A I N C H A S S I S
R E M O V AO
L F F R O N IP A N E A
L N D F R O N TS U B - P A N E L
To LowerFrontPonelAssembly
T o R e m o v eF r o n t P o n e
REARPANEL
DISPLAYBOARD
A l i g n m e notf t h eC h o n n eDl i o l
METER
SWITCHING
BOARD
DECODER
BOARD
MEMORYBOARD
POWER
SUPPLY
REGULATOR
BOARDPM37O
AF AND DISPLAY
REGULATOR
BOARD
POWER
TRANSFORMER
SHAFT
ENCODER
21-l
2t-l
lt-l
2t -2
21-2
21-2
LI-J
lt-J
2t-3
a\
I
21-4
214
2 t- 5
2l-5
lt-)
lt-3
21-6
zt-o
Chopter2l
RA. l77B Mointenonce
(i)
Contents
.j
.I]
A DT E D
O I
9=r=sl4AJ!_LL=!!9=4r)g==LE=-As=s=E=!!B=LJ=
INTRODUCTION
1.
T h i s c h o p t e r p r o v i d e s i n s t r u c t i o nf o r g o i n i n g o c c e s st o t h e p r i n f e d c i r c u i i b o o r d s ,
r e c e i v e r s u b - o s s e m b l i e so n d c h o s s i s - m o u n t e d
components. should it be necessory
to completely removeo printed circuit boord, o note should be mode of ihe cobleform
c o n n e c t i o n st o e o c h b o o r d . l n g e n e r o l , t h e r e - o s s e m b l yi s i h e r e v e r s o l o f t h e d i s m o n t l i n g
procedure.
I N I T I A LP R O C E D U R E
)
(l)
Set the front ponel POWERswitch to OFF.
(2)
Disconnectoll the coble connectors
ot the reor of ihe receiver,
(3)
Removethe two tronsitscrews,if fitted, throughthe reor ponel flonge
( s e eFi g u r e2 0 . 4 ) .
(4)
Removeihe four screwssecuringihe receiverto the rock or ioble-top
cobinet.
(5)
Withdrow the receiver ond ploce it on o flot cleon working surfoce.
(6)
R e m o v et h e r e c e i v e r t o p c o v e r p l o i e , i f f i i t e d , h e l d i n p l o c e w i t h D z u s
fosfeners.
BOARDPM532
To goin occessto the RFboordproceedos follows:
(l)
Removeihe top screeningcoverfrom ihe RF comporfment.
(2)
Locotethe couplingon the RFTUNE controlspindleond slqckenthe two
screws, Withdrowthe RFTUNE controlspindleto disengogethe coupling.
(3)
Disconnectihe cooxiol RFinpui connector.
(4)
Releoseihe two brocketfixing screwswithin the RF comportment
(lefih o n ds i d e ) .
(5)
The boord moy now be roisedfrom ihe reor to hinge ot the cobleform(front)
end. Once fhe boordis veriicol if moy be held in positionby sliding ihe
nylon bushinto the slot in the comportment
side memoer.
2t-l
RA. 1778Moinienonce
4.
To completelyremovethe RFboordfrom the receivermokeo note of, then unsolder,
the cobleformconnectionsto the boordpins.
- MAIN COMPARTME\T
pRrNTEp
BOARpS
CTRCUIT
box structuremountedon the receiverchossiscontoinsuP to seven
The comportment
prinied circuii boords,dependentupon ihe opiionsfitted. After the iop screening
cover hos been removed, eoch of theseboordsmoy be roised from ihe reor to hinge ot the
cobleform(front)end. Once o boordis veriicol ii moy be held in positionby sliding the
side member. To completelyremoveony boord
nylon bushinto ihe slot in ihe comportment
mokeo note of, ihen unsolder,the cobleformconneciionsto the boordpins. The boords
ore listedbelow.
fitted within the moin comPortmenl
5.
ISB IF/AF Boord PM364/3
Moin IF,/AFBoord PM364/l
lF Filter BoordPS367
AFC Boord PM664
LF Loop BoordPM588
Upper Loop BoordPM589
FSK BoordPM36B
toP cover.
The positionof eoch boord is indicoiedon the moin comportment
CIRCUITBOARDS- MAIN CHASSIS
PRINTED
in the die-cost
Five printed circuit boordsore contoinedwiihin comportments
boord,
removeihe screening
goin
to
o
occess
receiverchossis(seeFigure20,6). To
cover from the respective comportment. Eochboord moy be lifted cleor of the chossisby
removingthe securingscrewsond woshers. To completely removeo boord from the receiver,
moke o note of, then unsolder, the cobteformconnectionsfrom the boord pins. The boords
contoinedwithin the chossisore listedbelow.
6.
34 MHz Generotor BoordPM339
TronsferLoop BoordP5338
HF Loop BoordP5337
First Mixer BoordPS5l2
SecondMixer Boord PM336
REMOVALOF FRONT PANELAND FRONTSUB-PANEL
The front ponel togetherwith fhe front sub-ponelmoy be lowered os o complete
ossembly(porogroph8) to goin occessio the front ponel controls ond ossocioted
comportments,the meter switching boord, the shofi encoderond disploy, memoryond
decoderboordsond the componentsmountedon the front top foce of the die-ccst chossis.
Note thqt the receiver moy be sofely operotedwith the front ponel ossemblylowered.
7.
zt-l
RA. l77B Mointenonce
To LowerFrontPonel Assembly
8,
(l)
Removethe top screeningcover from the RFcomportment.Locotethe coupling
on the RFTUNE controlspindleond slockenthe two screws. Withdrowthe RF
T U N E c o n t r o sl p i n d l et o d i s e n g o g teh e c o u p l i n g .
(2)
Slide the receiverforwordsuchthot the botiom edge of the front ponel is cleor
of ihe workingsurfoce,
(3)
Removeihe six screws,eoch fitted with o nylon wosher,securingthe front
ponel to the receiver(threeot eoch edge, odiocent to eoch hondle). Do not
removeihe two screwsobove the tuning knob.
(4)
Supporlthe froni ponel ossemblyond remove the two recessedscrews, eoch
with o springwosher,locotedone odiocent to eoch hondle.
(5)
The front ponel ossembly
moy now be loweredto 'hinge' on the connecting
cobleform.
To RemoveFront Ponel
9.
10.
(l)
Usethe lorger(l/15in.) of the two socketwrenchesprovided(locotedin o
clip ottochedto the right-hondside member)to removethe control knob.
Usethe smollersocketwrench(l.5mm) to removethe BFO slow motiondiol.
To removeoll other front ponel knobs, lever out the centreof the knob, then
unscrewwith on Bmmbox sponner.
(2)
Disconnectihe two wiresto the front ponel meter, usingo 7mmsponner.
Replocethe nutsond woshers
for sofe keeping.
(3)
Removethe eight screws,eoch fitted with o nylon wosher,securingthe front
ponel lo the receiver (two in the centre of the front ponel ond three ot eoch
edge, odiocentto eochhondle.
(4)
Lift off the front ponel.
The front sub-ponelmoy now be loweredby disconnectingthe RFTUNE cont;'ol
spindle(Tunedversionsonly, seeStep (l) of porogroph8), ond removir:gthe two
screws,eoch with o springwosher,one ot eoch edge of the sub-ponel.
REARPANEL
I l.
The reor poreI moy be loweredto 'hinge' on the connectingcobleform. lt is
securedby sevenscrews,eochwith o springwosher, threeol eoch side ond one in
the cenlre, below the tronsistors
on the heot sink. Note thot the receivermoy be
sofelyoperotedwith the reorponel lowered,
RA. 1778Mointenonce
AP 116E_0?54_68
It is necessary !o l-ower the rear panel to gain access to Lhe regulalor board PM37,
t h e p o w e n s u p p l y s n o o t h i n g c a p a c i t o r s 1 C 1 a , 1 C 1 b ( m o u n t e d i n l i n e w l t h 1 C 3 ) , 1 C 2 a ,. 1c2b(mountedin1inewith1C2a)and1c3Lo1C6andneS13tor31R9'1R10.Twozener<
diodes, D5 and D6, are mounted on the inside of the rear panel.
To gain access to tbese
diodes it is firsl
necessary to remove the regulator board PM370 (see paragraph 20).
12.
>
DISPLAY BOARDPM692
13.
to
1U.
To gain access to the display board it j-s necessary to lower lhe front panel and
front sub-panel together as one assenbly (see paragraph 8).
Should it be necessary
proceed as folLows:conpletely remove the display board fron the receiver,
(1)
R e m o v el h e f r o n t
(2)
Lower Lhe front
(3)
Renove Lhe scnew securing
plate.
(4)
Bemove Lhe five
spacing pillars.
(5)
The display board may now be lifted
clear.
To cornpletely renove Lhe display
board fnon the receiver make a noue of, bhen unsolder the cableform connecting
wires bo Lhe board Dins.
Allgnment
panel- (paragraph !).
sub-panel assembly (paragraph 10),
Lhe display
screws securing
board earlh
the display
tag Lo tbe channel switch
board to the fronb
sub-panel
of the Channel- DiaI
15.
lfhen the Channel switch is set bo Channel 1, the swi.l:ch wipers are alnost in line
(viewed fron ihe front of
with but slightly
Lo the righL of the top spacing pj.llars
position,
the receiver),
in
WiLh lhe switch
this
Lhe 1 digit
on the channel diaL should
be posiLioned such that it appears cenLrally in the front panel channel wlndow.
M E T E RS W I T C H I N G
B O A R DP M 4 1 9
To gain access lo lhe meter switching board ib is necessary Lo ]ower the fronl pan
To compleLely
and front sub-panel Lcgether as one assenbly (see paragraph 8).
renove the nelen swiLchlng board and switch, proceed as folloHss16.
17.
(1)
R e m o v el h e f r o n l
panel (paragnaph 9).
(2)
Lower Uhe fronl
(3)
Remove the nut and washer securing
(4)
Withdraw Lhe neter
(5)
Make a note of,
sub-panel (paragraph 10).
switching
then unsolder
swibch to the front
lhe neter
sub-panel.
board and switch.
the cableform
connections
bo the board plns.
21-4
RA. 1778 Maj-ntenance
Andt 7 April 89
DECODER
BOARDPM694
'lB,
To goin occessto the decoderboord, lower the front ponel ond front sub-ponelos
one ossembly(porogroph
8), then removethe fwo M2.5 screwssecuringthe decoder/
memoryponel to ihe chossis. To removethe decoder boord from the receiver, proceedos
fol lows:19.
(l )
Removethe eighi screwsihot securethe decoderboordto the ponel. The
boord moy now be hinged owoy from the ponel.
(2)
To completely removethe decoderboord from lhe receiver, moke o note of,
then unsolder,the cqbleformconnectingwires to the boordpins.
MEMORY BOARDPM693
20.
To goin occessto the memoryboord, lower the front ponel ond front sub-ponelos
one ossembly(porogroph8). To removeihe memoryboord from the receiver,
proceedos fo llows:21 .
(l)
Removethe two M2,5 screwssecuringthe decodey'memory
ponel to the
chossis.
(2)
Removethe six screwsthot securethe memoryboordto the ponel ond unclip
the bottery. The boordmoy now be 'hinged'owoy fromthe ponel,
(3)
To completely removethe memoryboord from the receiver, moke o note of,
then unsolder,the cobleformconnectingwires io the boordpins.
POWERSUPPLYREGULATORBOARDPM37O
22.
To goin occessto ihe regulotor boord, lower the reor ponel (porogrophtl). To
completely remove the regulotor boord from the receiver proceedos follows;-
zJ.
(f )
Moke o note of, ihen unsolder, the cobleformconnectionsto the boord pins,
(2)
Removethe four screws,eoch with o flot ond o spring wosher, securingthe
boqrdto the insideof the reor ponel.
(3)
Lift out the boord.
AF AND DISPLAY
REGULATOR
BO,ARD
24.
To goin occessto the AF ond memoryregulotor boord, removethe sub-ponel
ossemblycontoiningthe frequencysiondordmoduleond, if fitted, the FSKreloy
ond borretter. This ossemblyis securedto the ccrt chcrsiswith four screws, eoch with o
spring wosher, To compleiely removethe boord, proceedos follows:-
2l -5
RA. 1778Mointenonce
25.
(l)
to ihe boordpins'
Moke o note of, then unsolder,the cobleformconnections
(2)
Removethe four securingscrews,eoch with o springwosher.
(3)
Lift out ihe boord '
TRANSFORMER
POWER
26.
27.
To goin occessto the connectionsto the power tronsformerond the supply input
proceedos follows:filter componenis,
(l)
I l).
Lowerthe reor ponel (porogroph
(2)
connectioncover plote.
Removethe four screwssecuringthe lronsformer
(3)
Removethe cover ploie.
To compleiely removethe power tronsformerfrom the receiver, proceedos
fol lows:(l)
Moke o note of, then unsolder, ihe cobleformconnectionsto the ironsformer.
(2)
Turn the receiver onio iis side (left-hond os viewed from the reor ponel).
(3)
contoiningthe
Removeihe screeningcover from the chcssiscomPortment
34MHz boord.
(4)
Removeihe nine screws, eoch with o spring wcsher, securingthe 34 MHz
boord.
(5)
Hinge out the 34 MHz boord on its cobleformio reveol the four tronsformer
securing screws.
(6)
Supportthe ironsformerond removethe four securingscrews.
SHAFTENCODER
28.
To removethe shoft encoderproceedos follows:(1)
Removethe tuningcontrol knob.
(2)
Lower the front ponel ond froni sub-poneliogeiher os one ossembly
(porogroph8).
(3)
Removethe three screwssecuringthe shoft encoderlugs to ihe inside of the
front sub-ponel,
21-6
RA. 1778Moinienonce
(4)
29.
To removethe shoftencodercompletely,moke o note of ihe connections,
ihen disconneclthe wiresfrom the poteniiometerboordof the reor of the
shoftencoder.
T o g o i n o c c e s st o t h e s e n s o rb o o r d o n d t h e g r o t i c u l e c o r r i o g e , p r o c e e d o s f o r r o w s : (l)
R e m o v ei h e b l o c k t o p e f r o m i h e o u t e r c o v e r ,
(2)
Locoie the opening in ihe outer cover, spring out rhe cover ond slide off,
(3)
T h e g r o t i c u l e c o r r i o g e i s s e c u r e db y t w o s c r e w s t h r o u g h i h e f r o n i f l o n g e
p l o t e ( s e eF i g u r e l 3 . l ) .
D o n o t r e l e c r e t h e s e s c r e w s u n l e s so b s o l u i e l y
n e c e s s o r y , T o d o s o m o y u p s e tt h e 9 0 d e g r e e p h o s er e l o t i o n s h i p b e t w e e n
the output signolsfrom the shoft encoder.
RA. l77B Mointenonce
C H A PT ER 22
F UNCTIONAL
TEST
PROCEDURES
CONTENTS
Poge
INTRODUCTION
T E S TE Q U I P M E N T
PRELIMINARY
DISPLAY
AND MEMORY
FREQUENCY
STANDARD
LOCALOSCILLATOR
OUTPUT
34 MHz OUTPUT
IN ITIALCHANNELPROGRAMMING
L HECK
I FA N D A F G A I N C O N T R O C
RE
ATTO
L FS T G N A LP L U S
NOISE/NOTS
H FS T G N A LP L U SN O T S E / N O TRSAET I O- ssB
REA T | O
H F S T G N A LP L U S
NO|SE/NOTS
RANGE
CHECS
K
AGC AND AF GAIN CONTROL
RFMETER
CALIBRATIC}.I
(SSB)
U L T I M A TSEI G N A LP L U S
N O I S E / N O I SRAT|O
E
S I N G L ES I G N A LS E L E C T I V I T Y
BFORANGE
S P U R I O URSE S P O N S
SLI G N A L S
TE
O EXTERNA
(IN BAND)
INTERMODULATION
CROSS
MODULATION
(AFCversions
AFCTESTS
only)
(FSK
FSKTESTS
versions
only)
RA, 1778 Mointenonce
zt- |
lt-
|
22-4
22-6
22-6
22-7
ll-6
22-8
22-9
22-10
ll-tl
22-13
22-13
22-14
aa
7/
lt-
to
ll-to
zz-t/
22-19
zl-zv
22-23
Chopter22
Contents(i)
CHAPTER 22
FUNCTIONAL
TEST PROCEDURES
INTRODUCTION
of the
to check the performonce
ThisChopiercontoinsdetoiled test procedures
out
port
of o
os
receiverogoinstthe Specificoiion, The iestsmoy be corried
scheduleor os on oid to the locoiionof o fquli. The tesisshouldbe
routine mointenonce
conriedout in the ordergiven.
I,
T E S TE Q U I P M E N T
2.
The itemsof test equipmentlisied below ore requiredfor the following tesh:(l)
Oscilloscope
FrequencyRonge:
d.c. to 100 MHz
Sensitivity:
l0 mV/cm
lmpedonce:
I M o shuntedwiih 20 pF
(Exomple: Tektronix Type 465 or Hewlett Pockord1702B
with i l0 (10 Mn /10 pF) probesT.
Q)
Signol Generotor
FrequencyRonge:
15 kHz to 70 MHz
Output Voltoge Ronge:
I prVto IV e.m.f.
' Ouiput lmpedonce:
50O
Amplitude Modulotion:
400 Hz 30/"
Distortion:
Lessthon l/o
(Exomple:Morconi Type TFl44H with 6 dB ottenuotor)
(Alternotives, not suitoble below 100 kHz, ore Hewleti Pockord
5069 or Rocol Type 9061/2).
/l-
RA. 1778Mointenonce
|
(3)
Multimeter
DC Voltoge Ronge:
0 ro 30ctv
AC Voltoge Ronge:
0 io 30O/ r.m.s.
DC CurreniRonge:
0to3A
(Exomple;AvometerModel 8)
(4)
Digitol FrequencyMeier
FrequencyRonge:
d.c. io 70 MHz
Accurocy:
tl count, with provisionfor exiernol
I MHz stondordinput (or I MHz outpuiot)0dBm)
Sensitivity;
50 mV r.m.s.
Inpui lmpedonce:
I Mo
shuntedwith 20 pF
Provisionfor rotio division is desiroble.
(Exomple: RocolType 9903 or 9905)
(5)
Ouipui Power Meter
FrequencyRonge:
20 Hz to 20 kHz
Input lmpedonce:
8o ond 600o
Sensitivity:
l 0 m Wf . s . d . m i n i m u m
o n dl 0 W
f,s.d. moximum
(Exomple:MorconiTF 8934)
(6)
Step Atienuotor
Ronge:
0 r o 1 0 0d B i n l 0 d Bs r e o s
lmpedonce:
50o
(Exompf
e: Somwellond Hutton lype 129)
lz- I
RA. l77B Mointenonce
(7)
HF ElecironicVolfmeier
Inpui lmpedonce:
High resistonceshuntedwith
copocitonce,with Probeio BNC
odoptor for 50o looa
Sensitiviiy:
300pV to 3V r.m.s.
FrequencyRonge:
l0 kHz to 100 MHz
(Exomple:RocolType 9031)
(B)
LF Electronic Voltmeter
lnpui lmpedonce:
I Mo minimum
FrequencyRonge:
200 Hz to 2 MHz
Sensitivity:
-50 dBmto +10 dBm
(with q 600o lood)
(Exomple: Advonce Type 77)
'
(9)
Wove Anolyser
(Exomple: DymorType 1771)
(10) BNC TerminotedCoble (3 off)
(l l)
lmpedonce:
50o
Length:
I metre
BNC Terminotion
50o
(12) BNC 'T' Adoptor
(13) Copocitor, 0.01 pF, CeromicDisc, 25V minimum'
( 1 4 ) R e s i s t oI r k, a , 5 / . , I W '
(15) ShortingLink - 300 mm, terminotedwith crocodileclips'
22-3
RA. l77B Mointenonce
PRELIMINARY
3.
(l )
Sei the receiverPOWERswitch to OFF,
(2)
Set ihe I MHz, 34 MHz, ond LO switcheson ihe reor ponel to lNT.
(3)
on the reor ponel is correctlyset to
Ensurethot the VOLTAGE SELECTOR
suit the locol supplyvoltoge.
(4)
Connectthe receiverto o suitoblesourceof o.c. Power'
(5)
Set ihe front ponel POWERswitch io ON.
(6)
Set the MEMORYswitch to TUNE.
17)
Ensurethot:-
(8)
(.)
the frequencydisployilluminotes.
(b)
ihe synthesizer
OUT OF LOCK lomp illuminotesond then extinguishes.
Sei the froni ponel METERswitch, in turn, to +20, +12, +5 ond -7. Check
ihot for eoch positionthe meterindicotionlies within the greenportionof
the melerscole.
DISPLAYAND MEMORY
4.
(l)
Set the CH,ANNELswitch to I .
(2)
Set fhe MEMORYswitch to TUNE.
(3)
Check thoi ihe disployilluminotes.
(4)
Set the TLJNING RATEswitch to eoch position in turn ond check thot
roioiion of the tuning knob chongesthe frequencydisploy os follows:-
TUNING RATE
Seiting
Chongein Disployed
Frequency
LOCK
None
SLOW
I kHz per rototionof knob in |0 Hz
srePs
MEDIUM
20 kHz per rototionof knob in 20 Hz
srePs
22-4
RA. l77B Mointenonce
Frequencydisploytoble conid.
T U N I N GR A T E
Setting
FAST
Chongein D isployed
Frequency
I MHz per rotoiion of knob in I kHz
steps(l0 Hz ond 100 Hz digits remoin
ot zero)
(5)
Tunethroughihe entire rongeof digiis to ensurethof oll digits ore complete.
(6)
Check thot leodingzeroson the l0 MHz ond I MHz digits ore not disployed'
(7)
Set rhe frequencydisployedio thot specifiedfor chonnel I in the following
toble ond turn the MEMORY switch to the sping-looded LOAD Posit;on'
then releose.
(B)
Repeoifor Chonnels2-12 occordingto the toble.
Chonnel
I
FrequencyDisployed(kHz)
l0 000.01
10 ill.ll
l0 222.22
l0 333.33
\t M4.44
7
22 5s5.55
*0t 666.66
I
*02n7.77
6
*00 888.88
l0
ll
t2
29 99.99
*07 999.99
17 999.99
* leodingzerosnot disploYed
22-5
RA. 1778Mointenonce
(9)
Set ihe CHANNEL switchto eoch chonnelin iurn ond check thot ihe
oppropriotefrequency,occordingto ihe obovetoble, io disployed,except
ihoi the l0 Hz digii shouldreodzero.
FREQUENCY
STANDARD(Allow I hourminimum
worm-uptime)
5.
(l)
Ensureihot the reor ponel 1 MHz ond LO INT/EXTswitchesore sei io lNT.
(2)
Connectthe digitol frequencymeterto the I MHz IN/OUT socket.
(3)
Ensurethot the digitol frequencymeterindicotes1000000Hz plusor minus
I Hz. lf the frequencystondordfitied is of the TXCO iype, odiustR'l on the
frequencystondordboordto ochieveo frequencywifhin ihese limits.
(4)
Disconnectihe digiiol frequencymeterfromthe I MHz IN/OUT socketond
connectin its ploce the HF electronicvoltmeter(50o input impedonce).
(5)
Checkthot the HF electronicvoltmeterindicotesoi leost 180nV,
(6)
Setthe I MHz INT/EXTswitchto EXTondensure
thot the HF electronic
voltmeterindicotionfollsto zero.
(n
Setrhe I MHz INT/EXTswiichro lNT.
LOCALOSCILLATOR
OUTPUT
6.
(l)
S e t i h e T U N I N G R A T Es w i t c ht o L O C K o n d i h e C H A N N E Ls w i t c ht o l .
(2)
Connectthe I MHz IN/OUT socketon ihe reor ponel of the receiverto the
I MHz EXTSTDsocketon the digitol frequencymeier. Set the digitol
frequencymeter io operote from on externol I MHz stondord.
(3)
Connecithe digitol frequencymeterto the LO IN/OUT socket.
(4)
Check thot the frequencydisployedon the digitol frequency meter corresponds
lo thot given for ChonnelI in the following toble. Repeotfor Chonnels
2 to 12.
NOTE: The frequencieswill only be os specifiedif the chonnelshove been
progrommedos in porogroph4 fl ond B),
22-6
RA. I Z/8 Mointenonce
Chonnel
Locol Oscil lotor Frequency
( d i s p l o y eodn d . f . m . ) ( M H z )
I
45.40000
z
45.51II0
45.62220
4
45.73330
46.84440
{7
04ACn
7
37.06660
U
38.17770
36.28880
IO
Aq ?ooon
il
43.39990
t2
{?
2000n
(5)
Disconnectihe digitol frequencymeierfrom the LO lN/OUT socketond
conneci in its ploce the HF electronicvolimeter (50e input impedonce),
(6)
Stepthe CHANNELswitch throughecch posiiion, i.e. I to 12, ond check
thot the electronicvolimeterindicotion is not lessthon IB0 mV for eoch
oosition.
(n
Set the LO INT/EXTswitchro EXT ond ensurerhot rhe HF elecironicvoltmeter indicotionfolls io zero.
(8)
Set rhe LO INT/EXTswirchro lNT.
(9)
Serrhe fronrponelMETER
swirchro DRIVELEVEL.
(lo) stepthe CHANNELswitchthrougheochposirionondcheckthot rhemeter
indicotionfollswithinthe 'V' portionof the meterscolefor eochposition
exceptChonnelI wherethe metershouldindicoteopproximoiely
holI
deflection.
34 MHz OUTPUT
'7
(l)
Connectthe digitol frequencymererto the 34 MHz IN,/OUTsocker. Ensure
thot the digitolfrequency
meterindicotes
34 000000Hz plusor minusI Hz.
RA. I 778 Mointenonce
(2)
Disconnectthe digitol frequencymeterfrom the LO IN/OUT socketond
connectin iis ploce the HF elecironicvoltmeter(50Q inpui impedonce)'
(3)
Checkthot the HF elecironic voltmeterindicotionis noi lessthon 180 mV'
(4)
Set the 34 MHz INT/EXTswiich to EXTond ensurethot the HF electronic
voltmeierindicotionfolls to zero'
(5)
Set the 34 MHz INT/EXTswitchto INT ond disconnectthe HF electronic
voltmeter, Referto Chop, 3, poro. 5 of OperotorsMonuol.
IN ITIAL CHANNEL PROGRAMMING
Beforeproceedingwith the remoiningtestsihe receiverchonnelsshouldbe
progrommed
to the following frequencies.The TUN ING RATEswitchshouldthen
be set to LOCK. Referto Chop.3, poro. 5 of OperotorsMonuol.
B.
Frequency(kHz)
Chonnel
3500.00
I
0 l B .0 0
050.00
A
990.00
5
28020.
00
6
I s020.00
7
8020.00
B
4020.00
1020.00
l0
5000.00
ll
3100.00
12
IF AND AF GAIN CONTROLCHECK
9,
(l)
Set the following controlsos indicoied:-
CHANNEL
MODE
I
SHORT
USB
22-B
RA, 1778 Mointenqnce
1
AFC (if fiffed)
I FG A I N
AF GAIN
LS
OFF
F u l l yC l o c k w i s e
FulIy Counter-Clockwise
ON
(2)
Turnthe AF GAIN progressively
clockwiseond check thot the noisein ihe
loudspeoker
incre:ses.
(3)
set the AGC switch to oFF. Turnt.he lF GAIN counter-c lockwiseond check
thoi ihe noisein ihe loudspeoker
decreoses.
(4)
Set ihe AGC swiich ro SHORT. Check thot the noise in rhe loudspeoker
increoses
to full output ond thot the lF GAIN control is inoperotive.
NOTE: In certoinreceiversihe lF GAIN controlmoy operofewith AGC. See
Appendix I in O perotor'sMonuor.
10.
(5)
Connectthe heodphones
ro rhe lefr-hond PHONESiock. Check thor rhe
noisein the loudspeoker
remoinsond ihot the noisecon olso be heordin the
heqdphones.
(6)
Tronsferthe heodphones
ro the righr-hondpHoNES iock. check thor there
is no output from the loudspeokerond thot noise con be heord in the heodphones.
( l)
Set the receivercontrolsos follow:C H A N N E L2
MODE
AFC (if fiited)
LS
2
USB
OFF
ON
(2)
Connect the output power meter to the LS ond E Terminolsof TSI on the reor
ponel. Set lhe output power meter io B.
(3)
(4)
Connect the CW outpui from the signol generotor, set to o frequencyof
l5 kHz qnd on ouiput level of l0 pV e.m.f., to the ontennosocket.
'
Tunethe signolgenerotorto the receiver.
(5)
serrheAGCswitchro sHoRT.
(6)
AdiusttheAF GAIN foron indicotion
of 100mWon theoutputpowermeter.
Zl-,
RA. I 778 Mointenonce
Set the AGC switch io OFF' Usingthe lF GAIN controlrestorethe AF
outpui to 100 mW on the output powermeter(0 dB referencepoint)'
0
(8)
Off-tune the signol generotorby ot leost l0 kHz. Ensureihoi the AF
outpui folls by not lessthon l5 dB.
(9)
Set the signol generotoroutpui level to 3 pV e.m-f.
(lO)
ll
(l)
Rep€otsteps(4) to (B)with the CHANNEL swiich set, in turn, to Chonnel3
ond Chonnel4.
osfollows:Setthe receivercontrols
CHANNEL
RFTUNE
AGC
MODE
AFC (if fiiled)
LS
5
WB
SHORT
USB
oFF
ON
(2)
to the MAIN lF OUTsocketon ihe
Connectthe HF electronicvoltmeter
reorponel(50Q inputimpedonce)'
(3)
Connect ihe CW output from the signol generotor, set to o frequency.of <-28.020 MHz ond on output level of I pV e.m'f. ' to the ontennosocket'2"vglll
(4)
Tune the signol generotorto the receiver for moximumresponsein the
receiver possbond.
(5)
Note ihe level on the HF electronicvoltmeter. Thisshouldnot be lessthon
5OmV.
(6)
Set the front ponel AM,/USBLINE LEVELond AF GAIN control fully clockwise.
(7)
Use the output power meter to meosurethe oudio output levels ot the following
points' The levelsshouldnot be lessthon thosegiven.
JACK
PHONES
600o
LOUDSPEAKER
TERMINALS
8o
'|
0mW
'I
w
4mW
600o
LINEO/P MAIN IF
(r8 )t o ( I 3 ) i n c l u i i v eo p p l vt o I S BR b c e i v eor sn l y '
N O T E ' . SePs
i u p(8
22-10
RA, I Z/g Mointenonce
(8)
Serthe MODEswiichio ISB-1.
(9)
Connectihe HF electronicvoltmeterto the ISBlF OUTsocket.
(10)
Tune the signol generotorfor moximumresponsewithin ihe receiver possbond.
(l l)
check thot the HF electronicvolimeterindicoiion is not ressthon 50 mV.
(12)
Sei the LSBLINE LEVELond AF GAIN conrrolsfully clockwise.
(13)
Use the outpui powermeter io m@surethe oudio output levels ot the
following poinis. The levelsshouldnot be lessthon thosegiven.
PHONES
JACK
600o
l0 mW
LOUDSPEAKER
TERMINALS
8o
lw
L r N EO / P
tsB
500o
4mW
(14)
Set rhe MODE swiichro USB.
(15)
Re-connectthe outpui power meter, set to go , to the loudspeokerterminols
(TSl LS ond E).
(16)
Set the signolgenerqtoroutput level to I pV e.m.f.
(17)
Tunethe signolgenerotorto the receiverfor moximumindicotion in the outpuf power meter.
(18)
Adiust the AF GA|N control for on indicotion of r00 mW on the outpui power
meter.
(19)
Set the AGC switchto oFF. Adiust the lF GAIN conrrolro restorethe AF
output to 100 mW (0 dB referencepoint).
DO NOT RE-ADJUST
THEAF OR IF GAIN CONTROLSFORTHEREMAINDER
OF
THIS TEST.
,,(20)
Disconnectthe signol generotorfrom the ontennosocket, ond check thot the
AF outpuf, os indicofed on ihe output power meter, folls by not lessthon
11-
RA. 1778Mqinlenonce
| |
(21) For receiversfitted wiih the RFTUNE conirol, retunethe signol generotor
to ihe receiver. Peokthe RFTUNE controlfor o moximumindicotionin the
ouipui powermeter. Check thoi this level is noi moreihon 6clBbelow the
l00mW reference leve' ,
(22) Repeoifor eoch of the following chonnels. DO NOT odiusi fhe AF or IF
GAIN controls.
Chonnel6
Chonnel7
Chonnel8
Chonnel9
- AM
HF SIGNTAL
PLUSNOTSE/NO|SE
RATTO
1?.
f\ l' ), /
Sef rhe rer:ciysr controlsos follows:-
CI-IANNEL
RFTUNE(if fitied)
AGC
MODE
FILTER
AFC (if fitted)
LS
(2)
8
WB
SHORT
AM
3kHz
oFF
ON
'
Connect HF electronic volimeier (50Q impedonce)to the Iv'lAIN IF OUT
socketon the reor pone..
(3) Set the signol generotoroutpui level to I.5prVe.m.f , CW.
(4) Tune the signol generoior to ihe receiver for moximumindicot on on the HF
elecfronicvoltmeter.
(5) Set the FILTER
switch to lkHz, 3kHz, 6kHz or 8kHz, os oppr.priote,
(6)
Set the signol generotorto give 70 per cent omplitude modulorionot 400H2,
(7) Adiust the AF GA lN control for on indicqtion of l00mW in the output power
meter (connectedbetween the LSond E terminolsof TSI).
(8)
-
Set the AGC swiich fo OFF ond use the [F GA lN control io restorelhe
l00mW indicotion on the ouiput power mefer,
(9)
Switch off the moduloiion ot the signol generciorond check thot the AF output
level folls by not lessthon the omountshownbelow ogoinst the oppropriole
fi lter.
l kHz 3kHz 6 k H zB k H z-
20dB
l5dB
l2dB
I ldB
22-12
RA.1778 lvloinienonce
(l)
Setihe receivercontrols
osfollows:CHANNEL
R FT U N E
MODE
AFC (if fified)
L5
I
WB
SHORT
USB
OFF
ON
Q)
Set the output level fromthe signol generotor(connectedto the onienno
socket) to 2 pV CW.
(3)
Tunethe signolgeneroiorio the receiverfor moximumresponse
within ihe
receiver possbond.
(4)
Adiust the AF GAIN controlfor on indicotionof 100mW on the outout
powermeter (connectedbeiweenthe LS ond E terminolsof TSI).
(5)
lncrecreihe output level from the signol generotorto 200 mV e.m,f. (+l0OdB
relotive to 2 pV) ond check thot the AF output level doesnot increoe by
moreihon 6 dB.
(6)
Resetthe signolgenerotor
outpuilevel to 2 pV.
(7)
Sei rhe AGC swirchro LONG ond repeorsreps(a) ond (5),
(8)
Sei the lF GAIN controlfully counter-clockw
ise,
(9)
Serrhe AGC swirchro OFF.
(10)
Checkthot theAF ourputlevel doesnotexceed100m'il.
(l l)
Serrhe AGC switchro SHORT.
RFMETER
CALIBRATION
14.
(l)
Set rheMETER
swiichto RF.
(2)
lncrecrethe output level from the signolgenerotorto 200 mV e,m.f.
(+100 dB relorive to 2 yy).
(3)
check thot the meter needle coincideswith the 100 dB mork on the meter
scole.
22-13
RA. 1778Mointenonce
15.
(4)
Reducethe signol generotoroutPutlevel in 20 dB stepsdown to 2 pV
(0 dB). Checkthot the dB reodingon the meteris wifhin plusor minus
l 5 d B o f f h e i n p u t l e v e l o t e o c hs t e p .
(l)
Set the receivercontrolsos follows:-
CHANNEL
R FT U N E
AGc
MODE
AFC (if fitied)
LS
I
WB
sHoRT
USB
OFF
ON
(2)
outputlevelto I mV e'm'f' (+60dB relotive
the signolgenerotor
Increose
to 1 pV).
(3)
Adiustthe AF GAIN controlfor on indicofionof 100mWon the output
powermeter.
(4)
qnd note
Connect the LF electronic voltmeter ocrossthe outPut Powermeier
the level indicoted.
(5)
Set ihe AGC switch to OFF.
(6)
Adiusr the lF GAIN conirol for on indicotion of 100 mW on ihe output power
meter.
@
Disconneciihe signol generqior from the ontennosocket'
(g)
check thot the reoding on the LF electronic voltmeter folls by not lessthon
50 dB, Disconnectthe LF electronicvolimeter'
(APPIicobleto the filten fitted)
SINGLE SIGNAL SELECTIVITY
16.
(1)
Connectthe signol generotorto the ontennosocket'
(2)
Connect rhe HF electronic voltmeter (50o impedonce)to the MAIN lF OUT
socket.
(3)
Connect the digitol frequencymeter, vio the high impedonceprobe' ocros
ihe HF electronicvoltmeter'
(4)
Set ihe AGC switch to OFF.
22-14
RA. 1778Mointenonce
(5)
S e tt h e F I L T E R
s w i t c hi o 0 . 3 k H z .
(6)
Set the MODE swiich ro AM.
(7)
Tune the signol generotorto the receiverfor moximumoutput c6 indicotedon
the HF electronicvoltmeter.
(8)
Adiust ihe lF GAIN controlfor on indicotionof 100mV on the HF electronic
voltmeter (0 dB reference),
(9)
Decreosethe frequencyof the signolgenerororuntil the HF electronicvolimeter indicotesminus6 dB relotive to the 0 dB referencelevel estoblished
ot step (7).
(10)
Note the frequencydisployedon the digiiol frequencymeter. rt shouldnot
be greoterthon 1399.85kHz.
(l l)
lncreosethe frequencyof the signol generqtoruntil the HF electronicvoltmeier ogoin indicotesminus6 dB relotive to the 0 dB referencelevel.
(12)
Note the frequencydisployedon the digitor frequencymeter. h shouldnot
b e l e s st h o n 1 4 0 0 . 1 5k H z .
(,l3)
Repeotthe proceduredetoil in steps (5) to (12) for the remoinderof rhe
filters fitted to the receiver, settingthe MoDE ond/or FILTER
switchesfo the
oppropriotepositionsin occordoncewith the following toble. check thoi the
6 dB limits ore os specified.
Filter
Type No.
8D.45858
8D.45859
8D.45274
8D.45275
8D.45694
8D.4s695
8D.45695
8D.45805
BD.45248
8D.45249
BD.45250
8D.45251
Mode/Filter
Switch Position
USB
LSB
USB
LSB
LSB
U5B
USB
AM l3 kHz
AM 8 kHz
AM 3 kHz
AM I kHz
AM 0.3 kHz
6 dB Bondwidths(kHz)
Not Les Thon
Not Greoter Thon
| ?oo 7
I 397.00
1400.30
1397.00
r 400.30
I400.30
1394.00
I 394.00
1403.0
I ?oo 7
I403.0
1406.
0
1399.7
1399.7
r 406.5
1404.0
l40r.5
r4 0 0 . 5
1400.
I
1396.0
r3 9 8 . 5
| 399.5
I399.9
22-15
RA. 1778Mointenonce
worm-uptime)
BFORANGE(Allowt hourminimum
17,
(l)
Sei ihe receivercontrolsos follows:CFIANNEL
RFTUNE (if fitted)
AGC
MODE
FILTER
AFC (if fitted)
LS
I
wB
SHORT
CW
SkHz
OFF
OI\
(2)
Connect ihe digitol frequencymeter ond the signol generotorto the receiver
onienno socket using o T connector'
(3)
Set the signol generotorfrequencyfor o reoding of 3 500.00kH2 on the
digitol frequencymeter.
(4)
Disconnectthe digitol frequency meterond re-connect it ocrossthe output
power meter (conneciedbetweenfhe LSond E ierminolsof TSI)'
(5)
set the AF GAIN control for o reoding of l00mw on the output Power meter.
Set ihe BFO control to '+"
(6)
(7)
Check thot the frequency indicoted on ihe digitol frequencymeter is within
the limits 3000H2to 4000H2 (if necessoryvory the BFo ADJUST control on the
34MHz generoiorboord occessiblethrougho hole in the boseof the receiver).
(8)
Vory the BFO control over the rongeond check thot o tone con be heord in
the heodphonesthot decreosesin frequencyto zero beot ond then increosesin
frequency.
(9)
Set the BFO controlto'-'.
(lo)
check thot the frequency indicoted on the digitol freguencymeter is within
the limits 3000H2to 4000H2.
(11)
Disconnectihe digitol frequencymeter.
TO EXTERNALSIGNALS
RESPONSE
SPURIOUS
'18
.
(f )
Set the receiver controlsos fol lows:CFIANNEL
RFTUNE(if fitted)
AGc
.I
wB
oFF
22-16
RA. 1778 lv'lointenonce
MODE
AFC (if fiited)
AF GAIN
lF GAIN
LS
USB
oFF
Mid-position
Fullvclockwise
ON
(2)
Set the signol generotorto o frequencyof 3,5 MHz CW ond the output level
to I yV e.m.f.
(3)
Tunefhe signol generotorio ihe receiverfor mqximumindicotionon the output powermeter.
(4)
Ad jusi the AF GAIN control for o reference level of 100 mW on the output
power meter,
(5)
Increosethe signol generotoroutpui level by 90 dB.
(6)
Tune the signol generoiorccrefully from 50 kHz to 3.48 MHz ond from
3.52 MHz to 36 MHz (ignorethosefrequencies
which ore direct subgenerotor
hormonicsof 3.5 MHz). Adiust the signol
output level os necessory
to restorethe I00 mW reference level for eoch spuriousresponseencountered.
Check thot the signol generotoroutput level required to restore the reference
output exceedsplus 80 dB relotive to I pV .
INTERMODULATTON
0N BANp)
19.
(l)
Set the receivercontrolsos follows:-
CHANNET
R FT U N E
AGC
MODE
AFC (if firred)
L5
I
WB
LONG
I tqR
OFF
ON
(2)
Connect lhe two signol generotors,designotedA ond B, to the combiner.
Connect the combineroutput to the step ottenuotor ond connect the output
of the step ottenuotorio the HF electronic voltmeter (50o input impedonce).
(3)
Set the stepottenuotorto 6 dB.
(4)
Set signol generotorA to CARRIEROFF ond odiust the output level of signol
generotorB, sei lo CW, for o reodingof l5 mV on the HF electronicvoltmeier.
Zl-l/
RA. 1778A4ointenonce
(5)
OFF, signol generotorA to CW, ond
Set signol generqforB to CARRIER
odiustthe output level of signolgeneroiorA for o reodingof l5 mV on the
HF electronicvoltmeier.
(6)
Disconnectthe HF electronicvoltmetermd connectthe siePottenuotoroutout to the receiveroniennosocket.
@
Connect the oufput Powermeter' set to 6000 , io the LINE OUTPUT^ AIN
lF terminolsof T5l on the reor Ponelof ihe receiver.
(B)
Connect the woveformonolyserocrossthe outPut Powermeter'
(9)
Set the LOAD switch on lhe woveformonolyserto OUT.
(10)
Conneci the digitol frequencymeter ocrossthe.woveformonolyser.
(l I )
Set fhe frequencyof signolgenerotorA for o reodingof I 100 Hz on the
digitol frequencymeter.
(12)
OFF.
Set signol generotorA to CARRIER
(13)
Set signol generotorB to CW ond odiust its frequencyfor o reoding of
1700 Hz on the digitol frequencymeter.
(14)
Disconnectthe digitol frequencymeier'
05)
Adiust ihe A A/USBLINE LEVELcontrol for on ouiPutof 4 mW on ihe ouiput
power merer'
(16)
Set signol generotorA to CW.
(14
Tune the woveformonolyserfor moximumoutput ot 1700 Hz.
(18)
Adiust the ottenuotoron the woveformonolyserfor on indicotion of 0 dB on
the woveformonolysermeter.
(19)
Tunethe woveformonolyserto the ll00 Hz signol qnd checkthot the level
indicoted on the woveformonolysermeter is 0 dB plus or minus I dB'
(20)
Tune ihe woveformonolyserto eoch of the following frequenciesin turn ond
check thot ony intermodulotionproduct meosuredis 40 dB or more below the
level of the wonted signolsot ll00 Hz ond 1700 Hz. The unwontedproducts
will oppeorot the following frequencies:500 Hz
600 Hz
2300 Hz
2800 Hz
22-18
RA. 1778Mointenonce
(21)
For ISBreceivers
only, set the MODEswitchto ISB-1. Tronsferthe output
powermeterto ihe ISBLINEOUTPUT
terminols
of TSl. Repeotsteps(10)to
(20). At step(15)odiustfhe LSBLINE LEVEL
conirotin ploceof the AM/
USBLINE LEVEL
conirol,
(22)
Disconnect ihe woveformonolyserond the output power meter.
CROSS
MODULATION
zu.
(l)
Setthe receivercontrols
osfollows:CHANNEL
AGC
MODE
FTLTER
AFC (if fiffed)
AF GAIN
lF GAIN
LS
IO
SHORT
AM
3 kHz
OFF
Mid-posirion
Fully clockwise
ON
(2)
Connect the iwo signol generotors,designotedA ond B, to the
combiner.
the
output fo the step ottenuotorond connect ihe output
!..:l-"":
.combiner
ot
fhe step oftenuotor
to the HF electronicvolimeter(50o input impedonce).
(3)
Sef the step ottenuotorto 6 dB,
(4)
set signol generotorA to GARRTER
oFF ond odiust the outpur rever of signol
generotor B, set to CW, for o reoding of 5 mV on fhe HF
electronic
voltmeter.
(s)
Set signol generotorB to CARRIEROFF, signol generqtorA to
CW, ond
odiust the output level of signol generotorA for o reoding of 5
mV on the
HF electronicvoltmeter.
(6)
Disconnectthe HF electronic voltmeter ond connect the step ottenuotor
output to the receiveroniennosocket.
(7)
Set signol generqtorB to CW ond reduce the output level of eoch
signol
generdtor by 30 dB,
(8)
t-he the digitol frequencymeter to set up the signol generotors
os follows:_
Signol Generotor A (wontedsignol)
5000,000kHz, 30 per cenr omplitudemodulotionot 400
Hz.
Signol Generotor B (unwontedsignol)
5 020.000 kHz, 30 per cent omplitude modulorionot 400 Hz.
22-19
RA. 1778Mointenonce
(9)
Connect the output power meter, set to Bo impedonce, between the LS
sf TSl.
o n dE t e r m i n o lo
(10)
Tunethe receiverio the wontedsisnol (A) for o moximumindicotion in the
outPutPowermeier.
(l l)
Adiust the AF GAIN control for on indicotion of 100 mW on ihe outPut
power meier (0 dB reference level).
(12)
Switch off the modulotionof the wonted signol (A) ond check thot the output
power meier indicotion folls by not lessthon 30 dB.
(13)
Increosethe level of ihe unwontedsignol (B) to obioin on indicotion on the
output power meter of I mW.
(14)
check thot the level of rhe unwonredsignol (B) is not lessthon 60 dB obove
signol (A), the wonted signol (to produceo crossmodulotionfigure of 3 per
cent) '
AFC TESTS(AFC versionsonly)
21.
(l)
Set the receivercontrolsos follows:MHz
I
kHz
RFTUNE
AGC
MODE
AFC
020.00
WB
OFF
FSKTUNE
OFF
lF GAIN
METER
LS
FullYclockwise
TUNECARRIER
ON
Tuningmeter
(2\
Check thot the front ponel meter indicotesfull scole.
(3)
Connect the signol generotor, set to o frequencyof 3.5 MHz ond on outPut
level of I mV e.m.f. CW, to the receiverontennosocket.
(4)
Tune the input signol to the receiver ond os the correct tuning position is
opprooched,check thot the meter reoding decreoes to the TUNE CARRIER
mork, ond beots ot o low frequency cs the qudio tone decreosesto zero beot'
22-20
RA. I 77BMqintenonce
Locking
(5)
With the receivercorrecilyiuned io the input signor, set the AFC switch to
F U L LC A R R I E R .
(6)
checklhot the AFC LocK lompilluminotes
ondthe meierindicotes
zeroon
the AFCscole.
(7)
Setthe AFCswirchio OFFondrhenro pILOTCARRIER,Checkrhotthe
AFCLOCK lompogoinilluminoies.
Accurocy ond hold ronge
(8)
Connect the digirol frequency merer ro the MAIN lF OUT socketond EXT
STDto the I MHz IN/OUT socketon the receiver, Setthe digitol frequency
meter for EXT STDoperotion ond sei the timebosero l0s. Ensure
thot the
frequencydispfoyed is | .4 MHz +2 Hz.
(e)
Set the TUNING RATEswirchro SLOW.
(10) Slowlyincreose
the receiverfrequency,ollowingihe AFC to lock up every
50 Hz, until the receiverfrequency
is 1.0205MHz.
(ll)
Ensure
thot the AFC LOCKlompis srill illuminoted.
(12) Slowlyretuneihe receiverto 1.020MHz.
( 1 3 ) Slowlydecreoseihe receiverfrequencyollowingthe AFC to re_lockevery
50 Hz, until the receiverfrequencyis 1.0195MHz.
(14) Ensure
thot the AFC LOCK lompis still illuminoted.
( 1 5 ) Retunethe receiverto I , 020 MHz.
Coptive ronge
(16)
Disconnectthe signol generotorot ihe receiver ontennosocket.
0n
Increosethe receiver frequencyby 50 Hz.
(lB)
Sei the AFC swirchro OFF ond rhen ro FULLCARR|ER.
(19)
Reconnectthe signol generotorto the receiver ontennosocket.
Q0)
Ensurethot the AFC LOCK lomp illuminoreswirhin l3 s.
22-21
RA. 1778Mointenonce
(21)
Retunethe receiverto l '020 MHz'
(22\
socket'
Disconnecithe signolgenerotorot the receiverontenno
(23\
Decreosethe receiver frequencyby 50 Hz'
(24\
Set the AFC switch to OFF ond then to FULLCARRIER'
(25)
socket'
Reconnectthe signol generoiorto the receiver onteno
(26)
l3 s'
Ensureihot the AFC LOCK lomp illuminqteswithin
(27)
Set the AFC switch to OFF'
(28)
Check thqt the meier indicotes full scole'
(2g)
tuning posiiion is
Tune the receiver to the input signol ond os the correct
the TUNE CARRIER
to
opprooched, check ihot the meter indicotion decreoses
mork.
(30)
set the AFC switch to
With the receiver correctly tuned to ihe input signol'
FULLCARRIER.
(31)
meter indicoteszero on
Check thqt the AFC LOCK lomp illuminotesond the
the AFC scole.
(32)
Ser the TUNING RATEswitch to LOCK'
MemorY
(33)
socket'
Disconnectthe signol generotorot the receiver dntenno
(34)
generotorto the receiver
After o period of one minute, reconnectthe signol
ontennosocket.
(35)
Checkthot the,AFCLOCK lomp is illuminoted'
AGC ronge
(36)
Set the METERswitchto RF'
Gn
Reducethe signol generotoroutPutto I PV e'm'f'
(38)
ond thot the front ponel
Check thot the AFC LOCK lomp is extinguished
meter indicotes0 dB.
22-22
RA, IZB Mointenonce
r
22.
(39)
Increqsethe signolgeneroioroutput to 3 prVe,m.f, ond check thot the AFC
L O C K l o m pi s i l l u m i n o t e d .
(40)
Switch AFC ro OFF, ond MODE ro USB. Ser rhe signolgenerororto l0 uV
e.m.f. ond tune ii io the receiverposbond. Meosureond note the voltoge
ot the DIV AGC terminolon the reor ponel usingthe digitol voltmefer.
Switch MODE to CW, BANDWIDTHto 3 kHz.
(41)
Tunethe signolgenerotorfor zerobeot on the iime corriermeier. switch the
AFC to FULLCARRIER
ond ensurerhot the LOCK lomp illuminotesofrer o few
seconds. Increosethe signolgenerotoroutput until the voltoge ot the DIV
AGC terminolis the someos thoi noied in step (40). Note the increosein
signol generotoroutputwhich shouldbe l0 dB +5 dB.
(42)
SwirchMODEro USB,AFC ro OFF. Repeorsreps(40)ond (41)for o signol
generotor
outputof 300uVe,m.f.
(43)
Ensurethot the AFC is locked, Sei the signol generotoroutput to 30 pV
e.m.f. Sef the AGC ro AAANUALond decreosethe lF GAIN until the AFC
LOCK lompstortsto flicker.
(44)
Switch to PILOTCARRIER
ond ensurethot rhe LOCK lomp illuminores
.
Decreosethe generotoroutput until the AFC LOCK lompstorisfo flicker.
Check ihot the decreosein level is 20 dB +5 dB.
(45)
Disconnectoll iest equipment.
(r)
Connecto wire link betweenthe FSK lN ond FSK OUT terminolsof TSI
on the reor ponel.
(2)
Connect the multimeter, set to the 100 V ronge, to the TEL O/p ond
TELE ierminols.
(3)
Set the receiverfront ponel controlso follows:-
CHANNEL
RFTUNE
AGC
MODE
FILTER
AFC
LS
I
WB
SHORT
FSK-N
I kHz
OFF
ON
zz-zJ
RA, 1778Mointenonce
(4)
Set the receiverreor ponel controlsos follows:-
8ov/6v .
N7P/N'
8ov
P
(5)
Check thot the multimeter reods+72 to +96V' Set the MODE switch to
FSK-Rond check thot o reodingof -72 to -96V is obtoined'
(6)
connec! rhe digirol frequencymeter to the high level/UNCAL outPutof the
signol generotorond sei the signol generolorfrequency to 3'50000 MHz
(+10Hz).
(7)
Connect the colibroted output of the signol generotorvio ihe stepped
otienuoior to the dntennosocket of the receiver. Set ihe generotoroutPui
tolpVe.m.f.ondiheottenuotorto0dB.Ensurethotthedigito|frequency
meterreodingis still 3.50000 MHz +10 Hz.
(8)
Set the receiverTUN ING RATEswitch to sLoW ond the METERswitchto
FSK OUTPUT. Increosethe receiver frequencyby 40 Hz ond note the meter
reoding.
(9)
Reducethe receiver frequencyby B0 Hz ond check thot the meter reoding is
in lhe oppositedirection to fhot obtoined in step (8).
(lO)
Set the ottenuotorto -6 dB cnrdrepeot steps(B) ond (9).
(ll)
Disconnectoll test equipment.
22-24
RA. l77B Mointenonce
AP I l6E-0754_68
gll3P=lE=E=a3=
gE=E
4=Ll=GJ!
$j_M =! E=os=LD=
!
CONTENTS
Pog.
INTRODUCTION
IESTEQUIPIvtEN
T
INITIALCHANNEL
PROGRAMMING
POWER
SUPPLIES
SHAFT
ENCODER
AND DISPLAY
BOARDPM592
SYNIHESIZER
SECTTON
LOWFRFQUENCY
LOOPBO,AR,D
PMsBB
UPPER
LOOPBOARDPM5B9
IRANSFER
LOOPBOARD
PS338
HFLOOPBOARDPS337
34MHzGENERAIOR
BOARD
PM339
RF/tF/AFSECTTON
MAIN IFIAFBOARDPM364II
tsBtFlAFBOARDPM364l3
TyptcALstcNAL LEVELS
|FAF BOARDS
(pM364)
FILTER
BOARDPS367
SECOND
MIXERBOARD
PM336
FIRST
MIXER
BOARD
PM335
RFBOARDPM582
pRocEDURE,
FINALSETTTNG-Up
pM364
\F/AFBOARDS
MAt N tFIAF BOARDPM364ll
lsB lFlAF BOARDPM364l3
MODEAND FILTER
SWITCHES
AFCBOARDPM664
FSKBOARDPM36B
FINAL SETTING-UPPROCEDURE,
5ECONDMIXERBOARD
MAf N tFIAF BOARDPM674/l
rsBtFlAF SOARDPM674/2
TYPICAL
SIGNALLEVELSIFIAFBOARDS
PM674
FINALSETTING.UP
PROCEDURE,
IF/AFBOARDS
PM674
MAtN lFIAF BOARDPM674/1
lsB lFlAF BOARDPM674/2
zJ- |
)7,-1
23-4
23-4
23-6
23-6
23-7
23-B
23-9
23-tl
23-14
n-v
23-18
23-21
23-21
23-28
n-31
n-35
zJ-+ z
23-43
n-45
n-46
23-48
z3-51
,?-{?
23-54
n-58
n-62
n-63
23-63
23-6s (
ILLUSIRATIONS
F i g. N o .
TuningCopociforSetting: l8 Degreepoint
RA.l77i3Mointenonce
zJ,l
Chopfer23
Contents
-l
INTRODUCTION
l.
for the receiveros o completeossembly.
This Choptercontoinsolignmentprocedures
for checkingthe performonce
of the receiverore given in Chopter22.
Instructions
Undernormoloperotingconditionsthe receiverwill mointointhe foctory olignment
over o long periodof time. Re-olignmentshould, iherefore,only be corriedout
which offect the
following ihe replocementof o printedcircuii boordor other componenis
olignmeni, or whereo knownmis-olignmentexists.
2.
Shouldit be necessory
to re-olign the compleiereceiver, the following
proceduresshould be cqrried out in the order given. Beforeottempting to re-olign
it mustbe crcerioined,whereopplicoble,thot the preceding
on individuolsub-ossembly
ore functioningcorrectly,
ossemblies
3.
4.
lf the specifiedperformonce
connotbe oiioined by olignment,then o foult
must be suspeciedond referenceshould be mode to Chopter21.
A certoin omountof dismonilingis necessoryto goin occessto cerioin oreosof ihe
ore conioinedin ChopterlB,
receiver, Detoilsfor dismontlingond re-ossembly
After olignment ensurethot oll dismontledossembliesore correctly recssembledond thot
oll screeningcoversore replocedusingoll the screwsprovided.
5.
The requiredtrimmingtoolsore providedwith eoch receiver; one is mounted
in o clip ottochedto the insideof the right-hondside ponel ond o secondis
(RFtuned versionsonly),
mountedwithin the RF comportment
6,
7.
When re-oligning coils it is importon!to ensurethot they remoinin tune in
operoiion. lt is necessory,therefore, to lock ihe core in position with either
white PTFEtope or o MCAl-oppoved core-locking compound. After reodiustment,old
PTFEtope shouldbe replocedwith new.
NOTE: DO NOT useo core-lockingcompoundtogetherwith PTFEtope ond DO NOT
use PTFEor compoundon coils with 'flocked' cores, i.e. thosewith colouredpowderon
the threodsof the core.
TESTEQUIPMENT
list of the test equipmentrequiredto corry out oll
The following is o consolidoted
ihe olignment proceduresgiven in this Chopter. The itemsof test equipment
ore given in the text
required for the olignmentof ony pcrticulor boord or sub-ossembly
under the oppropriotesub-heodingwith o cross-referenceto the item in this porogroph.
8.
23-l
RA. 1778Mointenonce
(l )
'l
Digiiol Voltmeter
Ronge:
Accurocy:
0 to l00V d.c'
To ihree figures
Type 9071)
(Exomple: Rocol Instruments
(2)
Oscilloscope,duol chonnel
Sensitivity:
FrequencyRonge:
100 mV Per centimetre
DC to l0 MHz
(Exomple: Tektronix lype 464 or Gould Advonce OS 3001)
(3)
Multimeter
(Exomple: Avomeier Model 8)
(4)
HF ElecironicVoltmeter (A)
Ronge:
Input lmpedonce:
Frequencyronge:
I to 20V
Not lessthon I 0 MQ
UP to 70 MHz
(Exomple: Rocol Instruments
Type 3l44)
(5)
HF ElectronicVoltmeter(B)
Ronge:
FrequencyRonge:
Input lmpedonce:
300 mV to 3V r'm.s'
Up to 70 MHz
50Q , 75O ond high impedonce
(Exomple: Rocol lnstruments
Type 9031)
(6)
LF ElectronicVoltmeter
Ronge:
Input lmpedonce:
3
-50 to +10dB(ddB= 0.775v)
Not lessthon I MQ
(Exomple: Advonce Type 77)
23-2
RA. l77B Mointenonce
(7)
Digitol FrequencyMeter
FrequencyRonge:
FrequencyStondord:
DC io 70 MHz
I MHz EXD STDsocketto be
connectedto I MHz IN/OUT socket
on the receiver
(Exomple: Rocol Insiruments
Type 9822 or Type 9021)
(8)
Signol Generotor (A)
FrequencyRonge:
O u t p u tL e v e l :
Outpui lmpedonce:
l0 kHz to 72 MHz
I m V t o 2 Y e . m . f.
75Q ond 50Q
(Exomple:Morconi TypeTFl44H wirh 50 to 75 Q mdching pod)
(9)
High PowerSignol Generotor (B)
FrequencyRonge:
Ouiput Level:
Outpui lmpedonce:
I to 30 MHz
I to 20V e,m.f.
75Q
(Exomple: Rohdeond SchworzType BN4l00l)
(l 0)
WoveformAnolyser
FrequencyRonge:
Input Level;
5 to 100 MHz
5 pV io 15 mV
(Exomple:Airmec Type2484)
(l l)
Output PowerMeter
FrequencyRonge:
Input lmpedonce:
PowerRonge:
20 Hz to 35 kHz
600Q ond 8Q
Not lessthon 2 W FSD
(Exomple: Morconi Type TF893A)
(12)
Step Attenuoior
Ronge:
lmpedonce:
0 ro 100 dB in I dB step
50O
(Exomple: Rocol InstrumenhType 90651)
IJ-J
RA. I 77B Mointenonce
(l 3)
.
50O BNCterminotion
(14)
Copocitor,0.01 pF, 50V
(15)
fixed, lkO,
Resisror,
5%, 0.25 W.
( 1 6 ) R e s i s t ofri ,x e d ,5 6 f ) , 5 % 0 , 2 5 W .
IN ITIALCHANNELPROGRAMMING
g.
Beforeproceedingwith the tests, chonnels I to 6 should be progrommedto the
fol lowing frequencies:
Chonnel
Frequency
I
1000.00
2
r7 990.00
29 999.99
4
7 999.99
t7 999.99
6
4 000.00
SUPPLIES
POWER
TestEquipment
10.
(l)
Multimeier- B(3).
References
I l.
(l)
C h o p t e1r 9 '
Procedure
12.
(l)
Lowerthe reor ponelof the receiver.
(2)
Connect the multimeter, set to fhe oppropriotevolloge ronge, between
chossisond eoch of the following pins on the regulotorboord, in turn, ond,
if necessory,odiust the oppropriotecontrol until the voltoge is within the
limits sPecified.
(3)
Connect the multimeterbetween pin 14 on the moin IF/AF boord ond chossis.
lfnecessory,odiustR3ontheAFondmemoryregulotorboordfororeoding
of +14.5V+100mV'
23-4
RA. 1778Mointenonce
AP I l6E-0754-6B
Aus.80 (r',rndt2)
REGULATOR
BOARDPIN
NOMINAL
VOLTAGE
VOLTAGE
LIMITS
ADJUST
22
+20
+ 100mV
Rl9
I6
+12
+ 50mV
RI7
t0
+5
*
-7
* 100mV
r00mV
p?
R8
(4)
Connect
the multimeter
between
pin 23 on the Disployboord(oronge/
brownwire)ondchossis,Checkthotfhemeterindicotes
+5V
+ 100mV.
(5)
Disconnect
oll testequipment
ondreplocethereorponel,
NOTE:
Throughout
the receiver,the followingcobleform
coloursoreused
for DCpowerdistribution:
+20V
+12V
+ 5V
- 7V
+4.5 V
Disploy+5 V
OV
RED
ORAI{GE
BROWN
VIOLET
RED/BLUE
ORAME/BROWN
BLACK
SHAFT
ENCODER
AND DISPLAY
BOARD
PA4692
TestEquipment
I3.
(l)
-8(2).
Oscilloscope
References
14.
(l)
C h o p t e1r 3 .
(2)
Chopter14,
Procedure
>
15.
Adiustment
of R4
(l)
Usingo duol troceoscilloscope,connectthe probefor chonnelA to
outputpin I on the shqftencoderpotentiometer
boord.
23-5
RAl778 lvlointenonce
AP r 16E-0754-6B
Aug.80(Amdt2)
(2)
Sei the oscilloscopeio disploy Chonnel A only'
(3)
Ensurethot the TUN ING RATEswitch is not in rhe LOCK position,
(4)
Whilst rototing the TUNE knob, check thot o squorewove is disployed on
(ottoched to the shoft encoder)for unity mork-fo-spocerotio.
(5)
Set the oscilloscopeto disploy Chonnel B only.
(6)
Whilst rototing the TUNE knob, check thot o squorewove is disployedon
unity mork-to-spocerotio.
Adiustment of shoft encoder
(7)
Set the oscilloscopeto disploy both chonnels' Trigger the oscilloscope
on the A Chonnelwoveform.
(8)
Whilst rototing the TUNE knob qnticlockwise, check thot woveformA
leodswoveformB by 90 degrees. Adiustmentshould n^otnormolly be
required but should the displocemenfbe other thon 90-, proceedos
fol lows;-
(9)
Removethe shoft encoder(Chopter2l) ond remove its cover. Slocken
the groticgle corriogescrewsond odiust the position of the corrioge
until o 90" phosedifference is ochieved. Tighten tfie corriogewhilst
mointoining fhe phosedifference.
('l0)
Replocethe cover ond refit the shoft encoder to the front ponel ossembly.
(ll)
Disconnectoll testequipment.
SECTION LOW FREQUENCYLOOP BOARDPM588
SYNTHESIZER
TestEquipment
16.
(l )
-8(2).
Oscilloscope
References
17.
(l)
C h o p t e2r .
(2)
Chopter24, FigurePM588'l.
23-6
R41778Mointenonce
Procedure
18.
Adiustment
of Tl
(l)
Conneclihe oscilloscope
beiweenthe iunction of Rl wiih D2, ond chossis
(0V), Adiust the core of tronsformerTl (l MHz input) for o moximumsignol
level, which shouldbe opproximotelyos indicotedin Chopter24, Figure
P M 5 B B. . I
Adiustmentof Ll
(2)
Set the receiverCHANNELswiich to Chonnel l.
(3)
Connectthe mulfimeter,set to the 2N d,c. ronge, betweenTPI (positive)
ond chossis(negotive).
(4)
Adiust Ll (6-7 MHz VCO) for o reodingof +l4V on the muliimerer.
Output Check
(5)
Meosurethe ouiput signol level from the 6-7 MHz VCO ot TP2 using the
oscilloscope. Theouiputshouldbe opproximotelyos indicotedin Chopter24,
F i g u r eP M 5 8 8 . l ,
Signol levels check
(6)
Usingthe oscilloscopeto monitor the test points specified in Chopter24,
Fig.urePM5BB.l ond check thot the signol levels ore within the limitssfoted.
?)
Disconnectoll testequipmeni,
UPPERLOOP BOARDPM589
TestEquipment
19.
(l)
M u l t i m e t e-r B ( 3 ) .
(2)
- 8(2).
Oscilloscope
References
20.
(l)
Chopter3.
(2)
Chopter24, FisvrePM589.1.
lJ-
RA. I 778 Moi.ntenonce
/
Procedure
21 .
Adiustmeniof L4
(l)
Sei the receiverCHANNEL switch to Chonnel2.
(2)Connectthemultimeier,settothe25/d.c'ronge,betweenboordpinT
(positive)ond chosis (negotive)'
(3)
Adiusi L4 for o reodingof +l4V on the multimeter'
Adiustmeniof Ll
(4)
Set ihe receiverCHANNEL switch to Chonnell.
(5)
Connectthe mulfimeter,set to the 25/ d.c. ronge, betweenTPZ(positive)
ond chossis(negotive)'
(5)
Adiusi Ll for o reodingof +l6V on the multimeter.
Signol levelscheck
0
Usethe oscilloscopeto monitoroll the pointsspecifiedin Chopter24,
FigurePM589.l ond check thot the signol levelsore within the limits stoted.
(8)
Disconnectoll test equipment'
LOOP BOARDPS338
TRANSFER
TesiEquipment
22.
(l)
O s c i l l o s c o p- eB ( 2 ) '
References
23.
(l)
Chopier4.
(2)
Chopter24, FisurePS338.1.
Procedure
There qre no odiusimentsfor this boord. Use the oscilloscopeto monitor.thetest
poinisspecifiedin chopter 24, Figvre PS3B8.lond check ihot the signol levels
ore within the limits stoted.
24,
23-B
RA. l77B Mointenonce
HF LOOPBOARDPS337
TestEquipment
25.
(l)
Digitol frequencymeter- 8(f .
(2)
HF etectronicvoltmeter(B) - 8 (5).
(3)
Multimeter- 8(3).
(4)
Oscilloscope- 8(2).
(5)
50O Bf..l
C Terminotion- B(13).
References
26,
(l)
Chopier5.
(2)
PS337.londPS337.2.
Chopter24, Figures
Procedure
27,
Adiusimentof 120
(l )
Set the receiverCHANNELswitch to Chonnel3.
(2)
Conneclthe multimeter,set to the 2N d.c. ronge, betweenboordpin l8
(positive) ond chossis(negoiive).
(3)
Connectthe I MHz EXTSTDinput of the digitol frequencymeterto the
I MHz IN/OUT socketon the reor ponel of the receiver, Set the digitol
frequencymeter INT/EXTswitchto EXT,
(4)
Connect the digitol frequencymeterbetweenboord pins 13 ond 14 (0V)'
(5)
Adiust 120 for o reodingof 8V on the multimeter. Check thot the digitol
frequencymeter indicofes947.826 kHz plus or minus I Hz. Disconnectthe
digitol frequencymeter.
Test point voltoge checks
(6)
Connect the multimeter. Set to the 25V d.c. ronge, betweenTP3 (positive)
ond chossis(0V). Checkthot ihe multimeterindicotes14 +lV.
23-9
RA. 1778Mointenonce
'"'
(7\
ihe positive
Setihe receiverGHANNELswitch!o chonnel2, Tronsfer
indicqtes
ihe
multimeter
to TP2. Checkthoi
leodof the multimeter
l4 +lV.
(g)
the positive
set ihe receivercHANNELswilchto chonnel4. Tronsfer
indicotesl4 -+lV.
to TPI. check thot ihe multimeter
leodof the muliimeter
Adiustmentof R38
(9)
Set the receiverCHANNEL switch to Chonnell.
(10)
Connectthe HF electronicvoltmeter,high impedonceinput, betweenTP4
ond chossis(OV)"
(ll)
Adiust R38for o reodingof lV r.m.s. on the HF electronicvoltmeter'
(12\
Step the MHz reoding through eoch incrementond check ihot the HF
electronicvolimeterindicoteslV +3 dB ot eoch increment'
(13)
betweenTP5 ond chdsis (0V), check thqt the
connect rhe oscilloscope
io the diogrom in Chopter 24, Figure P5337'2'
signol corresponds
of R44
Adiustment
(14)
input, betweenboord
connec!the HF electronicvoltmeter,high impedonce
pin 22 ondchossis(0V)'
(15)
AdiustR44for o reodingof 320mV r.m.s. +0.5 dBon the HF electronic
voltmeter.
of R50
Adiustment
(16)
to the Lo ll\,/oUT socket'
Connectthe 50Q terminotion
(17)
input, between
Connectthe HF electronicvoltmeter,highimpedonce
boordpin 24 ond chosis (0V).
(lB)
AdiustR50for o reodingof 220nY r,m.s. +0.5 dBon the HFelectronic
voltmeter.
of L4
Adiustment
(19)
sei to ihe 25V d.c. ronge,betweenthe iunction
Connectthe multimeter,
of 122with 123ond chossis(0V).
(20)
AdiusrL4 for o reodingof l4V on the multimeter.
23-10
RA. l77B Mointenonce
Ad justmentof L5
(21)
Set ihe receiverCHANN EL swirchto Chqnnel5,
(22)
Adiust L5 for o reodingof l4V on the multimeter.
*
Adiustmentof L6
(23)
Set the receiverCHANNEL switch ro Chonnel4.
Q4)
Adiust L6 for o reodingof l4V on the multimeter. Disconnectihe multimeter.
(25)
Connectthe multimeter,sei to the l0V d.c. ronge, betweenTPl0 (positive)
ond chossis(0V). Check thoi ihe multimeterindicotes3.5 +{.5V.
Disconnectthe multimeter.
Signol levelscheck
(26)
Use the oscilloscopeto monitor the test points in Chopier 24, Figvres
P5337,1ond PS337.2. Ensurethot the signol levelsore within ihe limirs
stoted.
(27)
Disconnecfoll tesi equipmeni,
34 MHz GENEMTOR BOARDPM339
TestEquipment
28.
(l)
- eB ( 2 ) .
Oscilloscop
(2)
Digitol frequencymeter- Bfl) .
(3)
Multimeter- 8(3).
(4)
Resistor,
564 - B(16).
References
29.
(l)
Chopter6.
(2)
Chopter24, FisuresPM339.londPM339.2.
Procedure
30.
Signol levelscheck
(l)
ser rhe AFC switch (if fitted) ro oFF.
23-l',l
RA, 1778Mointenonce
(2)
Ensurethot the 34 MHz INT/EXTswitch is sei io lNT,
(3)
Ensurethot the I MHz INT/EXTswiich is set to INT,
(4)
Uselhe oscilloscopeto monitoreochof ihe following poinis, Ensureihot the
woveformdisployedis within the limits definedin Chopter24, Figvres
PM339.I ond PM339.2.
TP3
PIN 4
PIN 6
PIN 8
TN
(5)
Sei ihe MODE switch to USB. Usethe oscilloscopeto monitorTP7. Ensure
ihqt the woveformdisployed is within the limits defined in Chopter 24,
Figure PM339.l ,
t
Adiustmentof T2
(6)
Connectthe oscilloscopeio pin l0 ond chossis. TuneT2. lf no chongein
level occursstop odiusiing; otherwisecontinueuntil no furtherchonge
occurs,
Adiustmentof R65
(7)
Corefully odiusi R65. lf no chongein level occursstop odiusting; otherwise
continue towords o moximumuntil no further chongeoccurs.
(8)
Connectihe digifol frequencymeierto boordpins l0 ond 3l (0V). Check
thot the digitol frequencymeter indicotes 1 400,000 Hz +1 Hz. Disconnect
the digitol frequencymeier.
(9)
Connect ihe oscilloscopeto boordpins I I ond 32 (0V). Check thot the
omplitudeof the 1.4 MHz woveformdisployedis 0.8V p-p.
Adiustmentof R4 ond L4
(10)
Connect the digitol frequencymeter to boord pins ll ond 32 (0V).
(l l)
Set potentiometerR4 fully clockwise,
(12)
Set the MODE switch to CW.
(13)
Set the front ponel BFO controlto +.
tJ-tl
RA. 1778Mointenonce
(14)
Adiusi inductorL4 for o digiiol frequencymeterindicotionof I 397.000Hz
+l 00 Hz.
()5)
Sei the BFO controlro -.
(16)
Adjusi R4 for o digitol frequencymeferindicorionof I 403,000 Hz +100 Hz.
(17)
Repeotsieps(.l3) to (16) until there is no furiher improvement.Disconnect
the digitol frequencymerer.
S i g n o ll e v e l sc h e c k
(18)
Usingthe oscilloscope
moniroreoch of the following points. Ensurethot the
woveform disployed is within the limits defined in Chopter24, Figures
P M 3 3 9 . lo n dP M 3 3 9 . 2 .
TPI5
PIN IO
PIN II
Ad[ustmeniof L2
(19)
Connect the digitol frequencymeter to the reor ponel 34 MHz IN/OUT
socket.
(20)
connect the I MHz lN/ouT socket on the reor ponel to the externol stqndord socketon the digiiol frequencymeier. Set the digitol frequencymeter
for externol I MHz stondordoperotion,
(2,|)
Connectthe multimeter,set to the l0V d.c. ronge, to Tpl (positive)ond
chosis (0V) .
(22)
Adiust L2 for o multimeterindicorionof l/.
Check rhot the digirol
frequencymeterindicotes34 000,000 Hz. Disconnecithe digiiol frequency
(23)
Disconnectthe mulfimeter. Connect the 55Q
lN/OUT socket.
resisforocrossthe 24 MHz
Signol levels check
(24)
Use the oscilloscopeto monitor the test points given in Chopter24,
Figures PM339.l ond PM339.2. Ensurethot the woveformsdisployed ore
w i t h i n t h e l i m i t sg i v e n .
ZJ-
RA. 1778 Mointenonce
IJ
SECTTON
RF/rFlAF
:L5
"o't
3r.
.-l
,o , roo*o*,*#'
(l)
Signolgenerotor- 8(B).
(2)
Digitol voltmeter- B(l ).
(3)
Digitol frequencymeter- B(7)
(4)
HF elecironicvoltmeter(B) - 8(5).
(5)
LF electronicvoltmeter- 8(6)'
(6)
Output powermerer- 8(l I).
V)
Multimeter- B(3).
(8)
R e s i s t o rl,k , 5 V " 0 . 2 5 W- 8 ( 1 5 ) '
References
32,
ChoPier 1 2 .
Procedure
NOTE:
IMPORTANT
The following olignment pocedures ore corried out with the moin IF/AF boord
isolotedfrom the remoinderof the receiver. Furtherminor odiustmentsore therefore
requiredfollowing the olignmentof the RF, first mixer qnd secondmixer boords.
ore given in poro. 71 and72.
Theseodiustments
(l)
Set the receiverfront-ponelcontrolsos follows:
(o)
(b)
(")
(d)
(e)
RF TUNE to WB.
AGC to OFF ond AFC to OFF.
lF GAIN fully counier-clockwise.
MODE to USBond USBBANDWIDTHto 3.
AF GAIN fully counter-clockwise'
(2)
Removelink I from the moin IF/AF boord.
(3)
Conneclthe multimeter,set lo the 100milliomp DC ronge, betweenfhe pins
of link l, with the negotiveleod of the multimeterconnectedto the pin
neorestthe edge of the boord'
(4)
R84for o reodingof l5 milliomp on the multimeter'
Adiust pofentiometer
23-14
RA.l778 Mqintenonce
(5)
Disconnectihe multimeierond replocelink l.
(6)
Unsolderthe cooxiql leod conneciedto pin 2 on the filter boord pS36Z
(the cooxiol screenmoy be left connectedfo pin 3),
(7)
Connectthe I kilohm resistorin serieswith the cmxiol leod connectedro
the 50-ohmoutputof the signolgenerofor(poro. B, item B) ond connect
ihe oiher end of ihis leod fo the cooxiol leod removedot operotion (6).
Connect the screenio pin 3 on the filter booro.
(B)
Conneci fhe digitol frequencymeter to the UNCAL socketon the signol
generolor.
(9)
Set the frequencyof the signol generoior to I.400MHz, plus or minus500H2
ond the output level to 60 microvoltse.m. f . -:r
! i."1
(10) Set the lF GAIN controlfully clockwise.
(ll)
Ensurethot the MODE swirchis sei ro USB,
(12) Ensurethot the AF GAIN control is set fully counier-clockwise.
.,/
,,
(13) Set potentiometersR3, R4 ond R42 fully counfer-clockwise.
04
Set potentiometer
R9 f ully clockwise.
(15) Connectthe h.f. electronicvoltmeter,high-impedonceinput, io TRl.
(16) ,Adiustinductors Ll ond L2 for q moximumindicofion on the h.f .
elecironic volfmeter.
(17) Adiust R9 for o level of 200 millivolrsot Tp3 ond then repeotoperorion(16),
(18) Sweepthe signol generoiorfrequencyfrom l390kHz to 14lOkHz. Note the
frequency ot which the peok output occurs, Also note the level of the peok
output.
(.l9) Sweepthe signol generotorfrequencyogoin from I390kHz to l4l0kHz.
Enzurethot the outpt-rtlevel remoinswithin l dB of the level noted ot
operotion ( l8) .
(20) Set the signol generotorto the frequencynoted ot operotion (lB).
(21) Adiusr R9 for on indicotionof 200 millivolts r.m.s. on rhe h.f. elecfronic
voltmeter (connectedto TP3).
23-r5
(22) Adiust R3 to reducethe h.f ' electronicvoltmeierindicotionio 100 millivolts ond ihen resetthe level to 200 millivolts with R9.
(23) Repeotoperotions(18) ond (19). lf the ldB toleronceof operotion(19)
connotbe met, repeotoperotions(16) to (23).
(24) Connectthe digitol voltmeterto boordpins29 (positive)ond 28 (OV)'
(25) Adiust R3l for on indicotionof L4 volts plusor minus25 millivolts on ihe
digitol volimeter.
(26) Tronsferthe digitol voltmerer to boord pins 30 (positive)ond 28 (OV).
(27) Adiust the lF GAIN control for on indicotionof I.4 volts plusor minus
l0 millivolis on the digitol voltmeter.
(28) Adiust R4 until the signol level ot TRl, os indicotedon the h'f'
by ldB. Disconnectthe volimeter'
electronicvolimeter,decreoses
(29) Reducethe signol generotoroutPut level by 4dB'
/
(30) Conn"ct the multimeter, set to the 25V DC ronge, betweenTP6
(positive)ond the -7 volt supply ot boord pin 20.
(31) Adiust R42 until the indicotion on the multimeter chongesfrom positive
7 volts * I volt .io Poritive 14 volts +l volt.
(32) Connectthe h'f. electronicvoltmeter, 50-0hminput impedonce,to the
MAIN lF OUT socketon the reor ponel.
(33) Set the AGC switchto SHORT.
(34) Set rhe frequencyof the signol generotorto l.400MHz plus or minus500H2
-i''a'.,,'
ond the output level to 60 microvoltse.m.f . (35) Ensurethot the lF output signol level, os indicofed on the HF electronic
v o l i m e t e r ,i s n o t l e s st h o n5 0 m i l l i v o l , tt . t . t .
_- ,,
Increosethe signol generoforoutput level by 70d8, Ensurethot ihe increose
in ihe lF outpui signol level is not greoter thon 5dB'
- - '':"-'
(37) Resetthe signolgeneroforoutpuf level to 60 microvoltse.m'f' Sei the
AGC switch to LONG ond repeot operoiions(35) ond (36).
(36)
(38)
Resetihe signol generotoroutPut level to
l0-gicrovolts
e.m.f'
23-16
M. 1778Mointenonce
I
(39) Connectthe electronicmuliimeler(poro. B, item 6) to boord pins I ond 9
(ov)'
(40) Tunethe signolgenerotorfor o moximumindicotionon the electronic
multimeter. Ensurethot the level indicotedis not lesst h o n 1 5 0m i l l i v o l t s
r.m.s.
(4.l) Disconnectthe eleclronicmultimeter. Connectthe woftmeterobsorption
set to B ohmsinput impedonce,beiweenihe LSond E terminqlsof TSI'
(42) Set the AF GAIN controlfully clockwiseond ensurethot the wottmeter
indicotion is not lessthon I /ott.
(43) Sei the AF GAIN conirol for on indicolionof
wottmeter.
.l00
milliwottson the
(44) Increosethe signol generotorouiput level by 70dB ond ensureihot the
^
wottmeierindicotionis not greoterthon 100 milliwoiis plus5 dB. -.
. -
(45) Reducethe signolgenerotoroutPutlevel by 60dB.
(46) Set the MODE swiichto AM.
(47) Set the signolgenerotorfor 30 per cent omplitudemodulotionot lkHz.
(48) Set the AF GAIN control fully clockwise ond ensurethot the wottmeter
indicoiion is not lessthon I wott.
(4e) Set ihe AF GAIN
control for on indicotion of I wott on the wottmeter.
(50) Connect o wire link betweenthe MUTE ond E ierminolsof TS2. Ensure
thot the wottmeterindicotion decreosesby not lessthon 40dB. Disconneit
the wire link .
(sl)
Set the MODE switchto USB.
_t_.1: .
f.
(52) Resetthe signol generotoroutPUtlevel to OOti".ou.-ott,
".t.
(53) Tronsferthe wottmeterobsorption, set to 600 ohmsinput impedonce,to
the LINE OUf PUTMAIN lF terminolsof TSI.
(54) Set the AM/USB LINE LEVELcontrol fully clockwise ond ensurethot the
wottmeterindicotionis not lessihon I0 milliwotfs.
(55) Sei the MODEswitchto AM '
23-17,
RA, l77B Mointenonce
(56) Set ihe signolgenerotorfor 30 per cent qmplitudemodulolionot lkHz.
(57)
Increoseihe signol generotoroutput level by 60dB. Ensurethot the
wottmeterindicotionis noi lessthon 4 milliwotts.
(5S) Switchoff ond disconnectoll iest equipment.
(59) Reconnectthe cooxiol leod, removedot operotion (6), to pin 2 on the
filter boord.
NOTE: See porogroph37 for typicol signol levels.
lsB/rF/AF BOARpPM364/3
Test Equipment
34.
The itemsof test equiprnenlrequired for the following test ore os listed for the
moin IF/AF boord, poro.3l.
References
35.
Chopter12.
hocedure
IMPORTANT
NOTE
The following olignment proceduresore corried out with the ISB IF/AF boord
isoloted from the remoinderof the receiver. Furtherminor od[ustments
ore
thereforerequired following the olignment of the RF, first mixer ond second
mixer boords. Theseodfustmentsore given in pro.72,
36.
(l)
Set the receiver front-ponel controlsos follows:
(o)
(b)
(")
(d)
AGC to OFF ond AFC ro OFF
MODE to LSB
lF GAIN f ully clockwise
AF GAIN fully counter-clockwise
(2)
Set potentiometersR3, R4 ond R42fully comfer-clockwise.
(3)
Set potentiometerR9 fully clockwise:
(4)
Lhsolderthe cooxiol leod connectedto pin 4 on the filter boord PS367
(the cooxiol screenmoy be left connecfedto pin 5),
23-l8
RA.lZ8 Moinienonce
(5)
Connectthe I kilohm resistorin serieswith the cooxiol leod connectedto
the 50 ohm output of the signol generotor(poro 8, item 8) ' Connect the
other end of this leqd to the cooxiql leod removedot operotion(4)'
Connectihe screento pin 5 on ihe filter boord.
(6)
Connectthe digitol frequencymeterto ihe UNCAL socketon ihe signol
generoTor.
(7)
Sei the frequencyof the signol generotorto l.400MHz, plus or minus500H2,
ond the output level to 60 microvoltse.m'f.
(B)
Connectthe HF electronicvoltmeter, high inpui impedonce,to TP3'
(9)
Adiust inductorsLl ond a for o moximumindicotionon the HF electronic
voltmeter.
(lO) AdiustR9 for o level of 200 millivolts r.m.s. ot Tftl ond then repeoi
operotion (9) .
(l l)
Sweepihe signol generotorfrequencyfrom I390kHz to l4lOkHz' Note
the fiequency oi which the peok output occurs. Also note ihe level of the
peok ouiPut.
(12) Sweepthe signol generotorfrequencyogoin from l390kHz to l4lOkHz'
Ensurethot the output level remoinswithin ldB of the level notedot
o p e r o t i o n( l l ) .
(.l3) Set the signol generotorto the frequencynofed ot operoiion (l l)'
()4) AdiustR9 for on indicotionof 200 millivolts r'm.s. on the HF electronic
voltmeter(connectedto TRI).
(15) AdiustR3 to reducethe HF electronicvoltmeterindicotionto
ond then resetthe level to 200 millivolts with R9.
.l00
millivolts
(16) Repeotoperotions(11) ond (.|2). lf the ldB toleronceof operotion(12) connot
be met repeot operotions(9) to (16).
(17) Connectthe digitol voltmeterto boordpins29 (positive)ond l8 (OV)'
(18) AdiustR3l for on indicotion of 1.4 volis plusor minusl0 millivolis on the
digitol voltmeter.
(19) Tronsferthe digiiol voltmeter to boord pins 30 (positive) ond 28 (OV)'
(20) Adiust ihe lF GAIN control for on indicotionof |.4 volts plus or minus
l0 millivoltson the digitol voltmeter.
23-19
RA.1778Mointenonce.
(21) Adiust R4 until fhe signol level ot TP3, os indicotedon the HF electronic
by ldB, Disconnectihe HF electronicvoltmeter.
voltmeier, decreoses
(22) Reducethe signol generotoroutput level by 4dB.
(23) Connecl lhe multimeter, sei io the 25V DC ronge, befween TP6(posiiive)
ond ihe -7 volt supplyot boordpin 20.
(24) AdIust R42 until the indicotion on the multimeter chongesfrom positive
7 volis + I volt to positive14 volts * I volt.
(25) Connect fhe HF elecironic volimeier, 50-ohm inpui impedonce,io fhe
ISB lF OUT sockef on the reor pcarel.
(26) Set rhe AGC swiich to SHORT.
(27) Set the frequency of the signol generotorto 1.400MH2 plus or minus500H2
ond fhe oufput level to 60 microvoltse.m.f.
(28) Ensurethot the lF outputsignol level, os indicotedon the HF electronic
voltmeter, is not lessthon 50 millivolts r.m.s.
(29)
lncreosefhe signol generotoroutput level by 70d8. Ensurethot the increose
in the lF outpuf signol level is not greoter thon 5dB.
(30) Resetthe signol generoioroutput level to 60 microvoltse.m.f. Set
the AGC switch to LONG ond repeot operotions(28) ond (29).
(St1 Resetthe signol generotoroutput level to 60 microvoltse.m.f.
(32) Connectfhe electronicmultimeter(poro.8, ifem 6) to
boord pins 8 ond 9 (OV),
(33) Tune the signol generotorfor o moximumindicotion on the electronic
multimeier. Ensurethot ihe level indicotedis not lessthon I50 millivolts
r.m.s.
(34) Disconnectthe electronic multimeter.
(35) Connect the wqttmeterobsorption, set to 600 ohmsinput impedonce,to the
ISBLINE OUTPUTterminolsof TSl.
(36) Set the LSBLINE LEVELcontrol fully clockwise ond ensurethot the wottmeter
indicotionis not lessthon 4 milliwotts.
(37) Sei the LSBLINE LEVELcontrol for qn indicotionof 1.0 milliwott on the
wottmeter.
23-20
RA.1778Mointenonce
(38)
ensure-thoithe
Increoseihe signolgenerqtoroutput.levelby 70dBond
5dB'
plus
wottmeierindicotionis not greoterthon l '0 milliwott
(39) Connecithe elecironicmultimeterocros the wqttmeterterminols'
(40) Adiust fhe LSBLINE LEVELcontrol for on output indicotionof l '0
milliwoti.
Ensure
(4.l) Connecto wire link betweenthe MUTEond E terminolsof TS2'
the wire
thot the ouiput level is reduced by not lessthon 40dB' Remove
l i n k.
(42) Swiichoff ond disconnectoll test equipment'
(43) Reconnectthe cooxiol leod, removedot oPerotion(4)' to pin 4 on ihe
fi lter boord.
(lF/AF boords)
TYPICALSIGNAL LEVELS
37 ,
test
The iypicol signol levels listed below were meosuredunder the following
conditionsunlessstoiedotherwise:to the
(l)
Signolgenerotor,output level set to 40pV e'm'f ' CW' connecled
lF inpui, pins34 ond 35 (filter boordoutPutoPencircuit)'
(2)
Receiverfront ponel controls sei os follows:-
MODE
Moin IF/AFboordr
ISBIF/AFboord:
USB
LSB
to&,*
flf'!"'""0*'*
(3)
of TF2, THI ond TP4were mode using ihe HF electronic
Meosurements
voltmeter(B), high input impedonce'
(4)
oi T7, pins 8/9 ond TF6 were mode using the LF electronic
Meosurements
voltmeter.
Tn
TP3
TP4
TW
PinsB ond9
Tl{
l 0 o m vr ' m ' s '
200mVr.m's' (setbYR9)
90 ond l30mVr'm's'
Between
50 ond90mVr'm's'
Between
Not lessthon l50mV,typicolly
between170ond250mVr'm's'
SignolgenerotoroutPutincreosedto
l20PV, omPlitudemoduloted307oot
50 ond90mVr'm's'
I kHz: Between
BOARDPS367
FILTER
38'Thereorenoodiustmentstobemodetothefilterboord.Sinceihefiltersoreseole
figuresgiven in the following
units, ony filtei thot foils to meetthe performonce
.
shouldbe rePloced
porogrophs
23-21
Mointenonce
RA.177B
Filter ldentificotion
A totol of six filters moy be fitted to the filier boord. Thesymmeiricolfilters fitted
(up to o totol of five) ore qs indicotedby the front ponel FILTERswitch morkings.
To oscertoinwhich sidebondfilters ore fitted, physicollycheck the drowingnumbersmorked
on FLI ond FL5 (seeFigure I I .l) ogoinstihe followingioble. Noie thqt on somereceivers,
for exomple, thoseequippedwith USBonly, o filter fitied ot FL5 will be o symmetricol
filter. A corrierfilier is only fitted (oi FL6) in receiversequippedfor AFC.
39.
DRAWINGNO.
BD45B06
8D45248
8D45249
8D45250
BD4525l
BD602856
BD45695
8D45694
sD45274
8D45275
8D45253
FILTER
l3 kHz Symmetricol
8 kHz Symmetricol
3 kHz Symmetricol
I kHz Symmetricol
300 Hz Symmeiricol
2.7 kP'z USBMqrine
6 kHz USB
6 kHz LSB
3 kHz USB(lSB)
3 k H z L S B( l S B )
Corrier
NOTE: Due to the inversionwithin the receiver, the filter selectedfor USBoperotionwill
ond thot selectedfor LSBoperqtionwill hove USBchorocteristics.
hove LSBchorocieristics
TestEquipment
40.
(l)
SignolGenerotor- 8(8).
(2)
Voltmeter(B)- 8(5).
HF Electronic
(3)
Meter - 8(Z).
Digitol Frequency
References
4 1.
C h o p t e1r 1 , F i g u r e2 0 . 5 .
Procedure
SymmetricolFilters
42.1
(l)
Removethe cooxiol socket from the chossis- mountedsecondmixer output
connector(right-hondfront, see Figure20.5).
n-n
RA. I 778 Mointenonce
(2)
Connectthe output of the signolgenerotorto the filter boord input vio the
cooxiol socketdisconnected
oi step (l),
(3)
Connecfthe digitol frequencymeterto the UNCAL outpufsockelon the
signol generolor (omit if Racol 9061/62 signol generoior is used).
(4)
Connectthe HF electronicvoltmeter,50Q
lF OUT socketon the reor ponel.
(5)
Set fhe receiverfront ponel controlsos follows:-
IFGAIN
MODE
FI L T E R
AFC (if fifted)
inpui impedonce,io ihe MAIN
F u l l yc l o c k w i s e
OFF
Widest bondwidth
(6)
Set the signol generotorfrequencyto 1.4 MHz ond the output level to
l 5 0 p V e . m . f.
0
Fromlhe following porogrophs,
30 io 35 inclusive, performthe tesisthot
ore opplicobleto the symmetricolfilters fitted to the receiver, setfingthe
FILTERswitch in eoch coseto the opproprioteposition.
l3 kHz SymmetricqlFilter
43,
(l)
Tune the signol generotorfor moximumouiput c6 indicoiedon the HF
electronic voltmeter. Ensureihot the output level is greoterthon 50 mV
e.m.f.
(2)
Set the lF GAIN controlfor on indicotionof 50 mV on the HF electronic
voltmeter.
(3)
Decreosethe signol generotorfrequencyuntil the output folls by 3 dB
relotive to the 50 mV level. Ensurethoi the frequencyindicotedon the
digiiol frequencymeteris lessthon 1.393 500 MHz.
(4)
Increosethe signolgenerotorfrequencyuntil the output folls by 3 dB
relotive to the 50 mV level. Ensurethot ihe frequencyindicoiedon the
digitol frequencymeteris greoterthon 1.406 500MHz.
B kHz SymmetricolFilter
44.
(l)
Tunethe signol generotorfor moximumoutput, os indicotedon the HF
electronic voltmeter. Ensurethot the output level is greoterthon 50 mV
r . m . s . w i t h t h e l F G A I N c o n t r o lf u l l y c l o c k w i s e .
IJ-ZJ
RA, 1778Mointenonce
(2)
Set the lF GAIN control for on indicotionof 50 mV on the HF electronic
voltmeter.
(3)
Decreosethe signolgenerotorfrequencyuntil the ouipui folls by 3 dB
relotive io ihe 50 mV level. Ensureihoi the frequencyindicotedon the
digitol frequencymeteris lessthon 1.396 000 MHz.
(4)
Increosethe signolgenerotorfrequencyuntil the output folls by 3 dB
relotive to the 50 mV level. Ensurethot the frequencyindicotedon the
digitol frequencymeier is greoterihon L404 000 MHz.
3 kHz SymmetricolFilter
45.
(l)
Tunethe signolgenerotorfor moximumoutpui, os indicotedon ihe HF
electronicvoltmeier. Ensurefhot the output level is greoterthon 50 mV
r . m . s . w i t h i h e l F G A I N c o n t r o lf u l l v c l o c k w i s e .
Q)
Set the lF GAIN control for on indicotionof 50 mV on the HF electronic
voltmeter.
(3)
Decreosethe signolgenerqtorfrequencyuniil the output folls by 3 dB
relotive io ihe 50 mV level. Ensurethot the frequencyindicoted on the
digiiol frequencymeteris lessthon 1.398 500 MHz.
(4)
lncreosethe signolgenerotorfrequencyuntil the outputfolls by 3 dB
relotive io the 50 mV level. Ensureihol ihe frequencyindicotedon the
digitol frequencymeteris greoterthon 1.401 500 MHz.
I kHz SymmetricolFilter
46.
(l)
Tune the signolgenerotorfor mqximumoutput, os indicotedon the HF
electronicvoltmeter. Ensurethoi the output level is greoterthon 50 mV
r . m . s . w i t h t h e l F G A I N c o n t r o lf u l l y c l o c k w i s e .
(2)
Set the lF GAIN control for on indicotionof 50 mV on ihe HF elecironic
voltmeter.
(3)
Decreosethe signolgenerotorfrequencyuntil the output folls by 3 dB
relotive to the 50 mV level. Ensurethot the frequencyindicotedon the
digitol frequencymeteris lessthon l.399 500 MHz,
(4)
Increosethe signolgenerotorfrequencyuntil the ouiput folls by 3 dB
reloiive io the 50 mV level. Ensurethot the frequencyindicotedon the
digitol frequencymeteris greoterthon 1.400 500 MHz.
23-24
RA. I778 Mointenonce
300 Hz Symmetricol
Filter
47,
(l )
Tuneihe signol generotorfor moximumoutput, os indicotedon the HF
elecironic voltmeter, Ensureihot the ouiput level is greoterthon 50 mV
r , m . s , w i t h t h e l F G A I N c o n i r o lf u l l y c l o c k w i s e .
(2)
Sei the lF GAIN controlfor on indicotionof 50 mV on the HF electronic
vollmeter.
(3)
Decreosethe signol generotorfrequencyuniil ihe output folls by 3 dB
reloiive io fhe 50 mV level . Ensureihoi ihe frequencyindicotedon the
digitol frequencymeier is lessthon 1.399 900MHz.
(4)
Increosethe signol generotorfrequencyuntil the output folls by 3 dB
reloiive to the 50 mV level, Ensurethot the frequencyindicotedon the
digitol frequencymeteris greoterihon 1.400 100MHz.
SidebondFilters
48.
For ssB versionsof the receiversei the MoDE switch to USBto check the USB
filter, ond io LSBto check ihe LSBfilrer (if fitied). For rsBversionsof ihe
receiverset the MODE switch to lsB-1. connect the HF electronicvoltmeier50e
input impedonce,to the MAIN lF oUT socketto check the USB-lsBfilter, to the lsB
lF oUT socketto check the LSB-lsBfilter. corry out the checksfor ihe sidebondfitted
in occordoncewith the following respeciiveporogrophs.
2 . 7 k 1 z U S BF i l t e r
49.
(r)
Tuneihe signol generotorfor moximumoutput, os indicofedon the HF
electronicvolimeter. Ensurethot the output level is greoterthon 50 mV
r . m , s , w i t h t h e l F G A I N c o n t r o lf u l l y c l o c k w i s e ,
(2)
Set the lF GAIN controlfor on indicotionof 50 mV on the HF electronic
voltmeter.
(3)
Decreosethe signolgeneroiorfrequencyuntil the output folls by 3 dB
relotive io the 50 mV level. Ensurethot the frequencyindicoiedon ihe
digitol frequencymeteris lessthon I.397 300MHz.
(4)
Increosethe signolgeneroiorfrequencyuntil the output folls by 3 dB
relotive to the 50 mV level, Ensurefhot the frequencyindicotedon the
digitol frequencymeteris greoterthon 1.399 650 MHz.
z,J-25
RA. l77B Moinienonce
3 k H z U S BF i l t e r
50.
(l)
Tunethe signol generotorfor moximumouiPut, os indicotedon the HF
electronicvoltmeter. Ensurethot ihe ouiput level is greoterthon 50 mV
r . m , s . w i t h t h e l F G A I N c o n t r o lf u l l y c l o c k w i s e .
(2)
Set the lF GAIN control for on indicotionof 50 mV on ihe HF elecironic
voltmeter.
(3)
Decreosethe signolgenerotorfrequencyuntil ihe outpui folls by 3 dB
thot the frequencyindicotedon ihe
relqtive to the 50 mV level, Ensure
.l.397
000 MHz'
digiiol frequencymeteris lessihon
(4)
Increosethe signolgenerotorfrequencyuniil ihe ouipui folls by 3 dB
relotive to the 50 mV level. Ensurethoi the frequencyindicotedon the
digiiol frequencymeteris greoterthon l'399 700 MHz'
3 k H z L S BF i l t e r
5l,
(l)
Tunethe signol generotorfor moximumouiPut, os indicotedon the Ht
electronicvoltmeter. Ensureihot the output level is greoterthon 50 mV
r . m . s , w i t h t h e l F G A I N c o n i r o lf u l l y c l o c k w i s e '
(2)
Set the lF GAIN controlfor qn indicoiionof 50 mV on the HF electronic
voltmeter.
(3)
frequencyuntil the ouiput folls by 3 dB
Decreosethe signolgenerotor
relotive to the 50 mV level. Ensurethot ihe frequencyindicotedon the
digitol frequencymeteris lessthon 1.400 300 MHz.
(4)
Increosethe frequencyof the signol generoioruntil the outputfolls by 3 dB
relotive to the 50 mV level, Ensurethoi the frequencyindicotedon the
digitol frequencymeteris greoterthon 1.403 000 MHz.
6 k H z L S BF i l t e r
52.
0)
Tuneihe signol generotorfor moximumoutput, os indicotedon the HF
electronicvoltmeier. Ensurethot the output level is greoterthon 50 mV
r , m . s . w i t h t h e l F G A I N c o n t r o lf u l l v c l o c k w i s e .
(2)
Set the lF GAIN controlfor on indicoiionof 50 mv on the HF electronic
voltmeter.
(3)
Decreosethe signolgenerotorfrequencyuntil ihe output folls by 3 dB
relotive to the 50 mV level. Ensureihot the frequencyindicoiedon the
digitol frequencymeteris lessthon 1.400 300 MHz.
23-26
RA. 1778Mointenonce
(4)
Increqsethe signolgenerotorfrequencyuntil the outpuifolls
by 3 dB
reloiive to ihe 50 mV level, Ensurethoi ine frequency
indicotedon ihe
digitol frequencymeteris greoterthon 1.406 000MHz.
3 k H z U S BI S BF i l r e r
5?
( l)
Tunethe signolgeneroiorfor moximumoutput, os indicoied
on the HF
electronicvoltmeter, Ensureihot the output level is greoier
thon 50 mV
r . m , s . w i t h t h e l F G A I N c o n t r o lf u l l y c l o c k w i s e ,
(2)
Sei the lF GAIN controlfor on indicotionof 50 mV on the
HF electronic
voltmeter.
(3)
Decreosethe signol
frequencyuntil the output folls by 3 dB
.genero.tor
relotive io the 50 mv
rever. Ensurethot the frequencyinai"otJa on1n"
digitol frequencymeteris lessthon 1.397 000 MHz.
(4)
Increosethe sign^olgeneroior frequency until the output folls
by 3 dB
reloiive to ihe 50 mV level. Ensurethot the frequency
indicqf'eaon the
digiiol frequencymeier is greoterihon 1.399 200 MHz.
k H z L S BI S BF i l t e r
(l)
Tunethe signol generoiorfor moximumoutput, os indicoted
on the HF
elecironicvoltmeier. Ensurethot the output ievel is greoter
thqn 50 mV
r.m.s. with the lF GAIN control fully clockwise.
(2)
Set the lF GAIN control for on indicotionof 50 mV on the
HF electronic
voltmeter.
(3)
Decreosethe signolgenerotorfrequencyuntil the output folls
by 3 dB
relotive to ihe 50 mV level. Ensurethot the frequencyindicoted
on the
digitol frequencymereris lessthon 1.400 300 MHr.
(4)
Increosethe signolgenerotorfrequencyuntil the outpuffolls
by 3 dB
relotive to the 50 mV level. Ensuretliot the frequencyindicoted
on the
digitol frequencymereris greoterthon 1.403 000 MH;.
CorrierFilter (AFCVersions
Only)
55.
(r)
on the fifter boordremovethe rink beiweenboordpins22 ond24.
Reconnect
the fink betweenboord pins 22 ond 23 .
(2)
Connect o temporqrylink beiween boord pins 7 ondB.
zJ-z/
RA. 1778Mointenonce
(3)
Unsolderond removethe white/block wire from pin I5 on the filter boord.
(4)
Set the MODE switch to USB.
(5)
Ensurethot ihe AFC swiich is set io OFF.
(6)
Ensureihot the AGC switch is set to OFF.
(7)
Connectthe HF elecironicvoltmeter,50Q
lF OUT socketon ihe reor ponel.
(8)
Tunethe signolgenerotorfor moximumoutput, os indicoiedon ihe HF
e lectronic voltmeter,
(9)
Set the lF GAIN controlfully clockwiseond ensurethqt the HF electronic
voltmeteris greoterthon 50 mV r,m,s.
inpui impedonce,io the MAIN
(10)
Set the lF GAIN control for on indicotionof 50 mV on the HF electronic
voltmeter.
(ll)
Decreosethe signol generotorfrequencyuntil the outpui folls by 3 dB
relotive to ihe 50 mV outpui level, Ensurethot the frequencyindicoted
on the digiiol frequencymeteris lessihon 1.399 950 MHz.
(12)
Increosethe signolgenerotorfrequencyuniil the output folls by 3 dB
relotive to the 50 mV level. Ensurethoi the frequencyindicotedon the
digitol frequencymeteris greoierthon 1.400 050 MHz.
(13)
Switchoff ond disconnectoll test equipment.
(14)
Removeihe link betweenboord pin 22 and 23. Reconnectthe link between
boord pins 22 ond 24.
(l5)ReconnectthewhiteA|ockwireioboordpinl5removedotstep(3)
(16)
Reconnectthe cooxiol socket to ihe chossismountedsecondmixer output
Plug.
BOARD
PM336
sECONDMIXER
TestEquipment
56.
(l)
Signolgenerotor- 8(8).
(2)
HF electronicvoltmeier(B) - B(5).
zJ- to
RA. l77BMointenonce
(3)
Multimeter- 8 (3).
(4)
C o p o c i t o0r . O l p F - B ( 1 4.)
References
57,
C h o p i e r1 0 .
Procedure
58,
A d i u s t m e not f L l 0 , L 1 2 , L l 3 o n d L l 4 .
(l)
Removelinks I ond 2 from the boord.
(2)
Set ihe froni ponel AGC switch to OFF.
(3)
Set ihe lF GAIN controlfully counierclockwise.
(4)
Ensurethot the 34 MHz INT/EXTswirch is ser ro lNT.
(5)
connect the HF electronicvoltmeter,50e inpur impedoncebetweenlink
2 (pin odiocent to rhe screen)ond Tp2 (O/) .
(6)
Adiusf inductorsLl0, Ll2, Ll3 ond Ll4 for o moximumindicotionon the HF
e lectronic voltmeter.
0
Repeoistep (6) until there is no increosein output.
(8)
check thot ihe HF electronicvoltmeterindicotion is not lessthon 500 mV
Adiustmeniof Ll5
(9)
Disconnectfhe HF electronicvoltmetercrrd replocelink 2.
(10)
Ser ihe MODE swiich ro USB.
(l l)
Connectthe HF electronicvoltmeter, HIGH impedonce,to pins 2 ond 3
(ground)of the filter boord.
(12)
Connectthe signolgenerotorvio the 0.01 pF copocitorbetweenlink I
(pin furthest from the screen)ond Tp2 (0V) on the secondmixer boord.
(13)
Set the signol generororto o frequencyof 35.399 MHz +500 Hz.
(14)
Sei ihe output level of ihe signolgenerotorfor on indicotionon the HF
electronic voltmeterof 100mV r.m.s.
ZJ- IY
RA. 1778Mqintenonce
(15)
TuneLl5 for o moximumindicotionon the HF electronicvoltmeter,
to mointoinon
odiustingthe outPutof the signolgenerotoros necessory
i n d i c o t i o no f 1 0 0m V r . m . s .
(16)
check thot the signolgeneroiorouiput level doesnoi exceed30 mv e,m.f.
A d i u s t m e noi f 1 1 , 1 6 , 1 7 , L B , L 9 o n d L l l
0n
Disconnecithe signol generotorond copocitor.
(18)
Replocelink I on the secondmixer boordPM336.
(19)
Removelink I on ihe first mixer boordPM335.Sei R8 fully clockwise'
(20)
connect the output of the signol generotor, set to o frequencyof 35.399 MHz
to the T3 end of link I on the first mixer boord PM335,
(21\
Set the signolgenerotorouipui level for on indicotionon the HF electronic
voltmeterof 100 mV r. m.s.
Q2)
Tune inductorsLl , L6, L7, 18, L9 ond Ll I for moximumoutPut 6 indicoted
on the HF electronic voltmeter, Repeotuntil there is no further improvement.
Adiusimentof RB
'l00
mV on the
(23)
Resetthe signol generotoroutPut level for on indicotion of
HF electronicvoltmeter.
(24)
Checkthot the signolgenerotorouiput level is lessthon 4 mV e'm'f'
eA
Connect the multimeier to pin B (positive)ond chossis(negotive)' Set the
lF GAIN control so thot the multimeterindicotes2 ' lV d' c'
(26\
Adiust RBuntil the HF electronicvoltmeterreods95 mV'
Qn
Adiust the lF GAIN control to give on indicotionon the multimeterof 2.8V.
(28)
Check thot the indicotionon the HF electronicvoltmeterfolls ond increose
the output of the signol generotorsufficiently to produceon indicotion of
100 mv. check thot the signol generotoroulput requireson increoseof ot
leost 38 dB io ochieve ihis reoding.
(29)
Replocelink I on the first mixer boord PM335.
(30)
Disconnbctoll test eguipment.
23-30
RA. 1778Mointenonce
FIRST
MIXERBOARDPM335
TesiEquipmeni
59,
(l)
Signolgenerotor- 8(8).
(2)
HF electronicvolrmerer(A) - B(4).
(3)
HF electronicvolrmerer(B) - B(5).
References
60.
Chopier9.
Procedure
6l .
(l )
Set the receiver controlsos follows:CHANNEL
RFTUNE
LO |NT^XT
MODE
AFC (if fiited)
AGC
lF GAIN
q
I
WB
EXT
USB
OFF
OFF
Fullyclockwise
Connectihe signol generotorto the LO IN/OUT socketon the reor ponel.
Set the frequency of the signol generotorto 36 MHz ond the ouiput ievel
to 880 mV e.m.f. (+6 dBm).
Adiustmentof TI , L6 ond T2
(3)
Connecithe HF electronicvolrmeter(B), high impedonceinput, to Tp3.
(4)
Sweepthe frequencyof the signol generotorfrom 36 to 40 MHz. Noie the
level of the peok responsec indicoted on ihe HF electronic voltmeter (B).
(5)
Set the signol generotorto o frequencyof 35.415 MHz.
(6)
TuneTl, L6 ond T2 to obtoin on output on the HF electronicvoltmeter(B)
of =5 dB relotive to the peok responsenoted ot step (4).
Voltoge levels check
(7)
Connectthe HF electronicvolrmerer(B) to Tp5.
ZJ-J I
RA. l77B Mointenonce
(B)
Sweepihe frequencyof the signol generotorfrom 35.415 MHz to 39'4 MHz'
Check thot the level indicotedon the HF elecironicvoltmeter(B) remoins
w i t h i n - 6 d B o f t h e p e o ko u t p u il e v e l .
(9)
Set the signol generotorto o frequencyof 35'400 MHz. Check ihot the
level indicotedon lhe HF electronicvolimeierfolls by not lessthon 25 dB,
Adiustmeniof 14, 15, L7 ond LB
(10)
Set rhe front ponel CHANNEL switch to 6.
(ll)
Connecithe HF elecironic voltmeier(B), high inpui impedonce,to TP4.
(12)
Sei the signolgenerotorto o frequencyof 35.400 MHz.
(.l3)
AdiustL5 ond L7 for o minimumindicotionon ihe HF elecironicvoltmeter(B).
(14)
Set the signol generotorio o frequencyof 50.600 MHz.
(15)
Adiust 14, L8 ond L9 for o moximumindicotionon the HF electronic
voltmeter(B).
(16)
Sweepihe frequencyof the signol generoior from 39.400 to 65'400 MHz.
Check ihot the level indicotedon the HF electronicvoltmeier(B) remoins
within -6 dB of the peokoutput level.
[4
Disconnecithe HF electronicvoltmeter(B).
(lB)
Connectthe HF electronicvoltmeter(A) to boordpin 30.
(19)
Sweepthe frequencyof the signol generotorfrom39.4 to 65'4 MHz. Check
ihot ihe indicotionon the HF electronicvoltmeter(A) remoinswithin the
limits 6 to l5V over the frequency ronge. lf necessoryreodiusfL4, L5' L7
o n dL B .
(20)
Set the CHANNEL switch on the front ponel to 1 .
(21)
Sweepthe frequencyof the signol generotorslowly from 35'415 to 39.400
MHz. Check ihot the indicotionon the HF electronicvolimeter(A) remoins
within the limits 6 to l5V over the frequencyronge. Disconnecithe volve
voltmeter.
:
Adiustmentof R39
Q2)
set the front ponel METERswitch io DRIVELEVEL.
23-32
RA. 1778Mointenonce
(23)
Set the LO INT/EXTswitchon the reor ponel to INT ond disconnectrhe
signolgenerotorfromthe LO lN,/OUT socket.
(24)
Adiust potentiometerR39to set the front ponel meier needle to the centre
of the V portionof the scole.
Voltoge level check
(2q
Set the receiverCHANNELswitch to l.
(26)
Connect the ouipui of the signol generotorto ihe chossismountedfint mixer
inpui BNC connector(seeFigure20.5). Set the signolgenerotorfrequency
to 1.000 MHz ond the outpui level to 5 uV e.m.f.
Q7)
Connectthe HF electronicvoltmeter(B), 50O input impedonce,io the
MAIN IF OUT socketon the reor ponel,
(28)
Tune the signol generotorfor moximumoutput, os indicoted on the HF
electronicvoltmeier(B). Ensurethot the output level is not lessthon
50 mV r,m.s,
(29)
Set the receiver frequencyto 3.999 MHz.
(30)
Set the signol generotorfrequencyto 4 MHz.
(31)
Tunethe signolgenerotorfor moximumoutput, os indicotedon the HF
electronic voltmeter(B). Ensurethoi the output level is not lessthon
5 0 m V r . m .s .
(32)
Set the receiverCHANNELswirchio 6.
(33)
Tune ihe signol generotorfor moximumoutput, Ensurethot the output level
is not lessthon 50 mV r.m.s.
(34)
Sei ihe receiverCHANNELswirchto 3.
(35)
Set the signol generotorfrequencyto 29.9 MHz.
(36)
Tune the signol generotorfor moximumoutput. Ensurethot the output level
is not lessthon 50 mV.
NOTE l: Typicol signollevelsot the remoiningtest pointsnot olreodycovered
ore listed below:-
4 to 29, HF electronicvolrmeter
(B)high
Tpl. MHz switchsettings
impedonce
input, lV r. m.s.
23-33
RA. l77B Mointenonce
TP2: MHz swiich seitings0 to 3, HF electronicvoltmeter(B), high input
i m p e d o n c eI, , 2 V r . m .s .
\
TP6: HF electronicvoltmeter, high input impedonce(B), 900 mV to l.2V
r. m. s. dependenton MHz switch seiiing.
NOTE 2: lf the ouiput signol from ihe first mixer is very low, i,e' in the order
of -10 dB, o foilure of one or moreof the field-effect tronsistors,TR3'TR4,TR6,
TR7shouldbe suspected. Usethe following procedureto oscertoinwheiheror not
ihe mixer tronsistonore functioningcorrecily.
62.
(l )
Set the receiverPOWERswitch to OFF.
@
Unsolderond remove the bore tinned copper (BTC)wire link from boord
orn lJ.
(3)
Connect the positive ouipui from o 5V supply vio o multimeier, set to the
100 mA d. c, ronge, io the BTClink wire removedot step @). Connecithe
negotive leod from the 5V supply to chossis(0V),
(4)
Set the receiver PO\{ER switch ro ON.
(5)
Switchon the 5V supply. Thecurrenidrownfromthe 5V supplyshouldbe
between20 qnd 35 mA, lf the currentdrownis lessthon 15 mA or greoter
thon 40 mA, TR3ond/or TR4shouldbe reploced.
(6)
Swiichoff ond disconnectthe 5V supply.
A)
Setthe receiverPOWER
swirchio OFF.
(8)
the BTCwire link io boordpin 15.
Reploce
(9)
To checktronsistors
TR6ondTR7,proceedos follows:-
(10)
the BTCwire link fromboordpin 17.
Disconnect
(l I )
setto the
Connectthe positiveoutputof the 5V supplyvio the multimeter,
100mA ronge, to the link wire removedfromboordpin 17. Connectthe
negotiveleodof the 5V supplyto chcsis(O/),
(12)
switchto ON,
Setthe receiverPOWER
23-34
RA, 1778Mointenonce
l
(13) Switchon the 5V supply. The currentdrownfrom the 5V supplyshouldbe
beiween20 ond 35mA. lf the currentdrown is lessthon l5rnA or greoterihon
40mA, TR6ond/or IR7 shouldbe reploced,
NOTE: Beforeremovingo (possiblyserviceoble)field-effect tronsistorfrom the
boord, wrop o piece of ihin BTCwire roundthe fronsisiorleods(beiweenthe bose
of the ironsisiorond the boord), A new field-effeci ironsisforshouldbe suppli,ed
with o shortingconduct ive-rubberring over the tronsistorleods. The ironsistorleods
shouldremoin short-circuited until oll the leodsore solderedto the printedcircuit
boord.
RF BOARDPM582
Tesi Equipment
63.
(l )
Sisnol sererotor(A) -B(B).
(2)
High powersignol generotor(B) -B(9).
(3)
Digiiol frequencymeier -8(7).
(4)
HF el ectronicvolimeter(A) -B(4),
(5)
HF elecrronicvolimeter(B) l8(5).
(6)
Woveformonolyser-B(10).
(7)
Multimeter-8(3).
References
64.
ChopterB,
Procedure
65.
(l)
Roiseihe RFboordto the uprightposition.
(2)
Set the RFTUNE controlfully counter-clockwise(the W/B posirion).
(3)
Set the front ponel CHANNEL switch to ony postionfrom I to 6.
(4)
Connect the output from signol generotor(A) to the RF inpui socket on the
boord.
23-35
RA.1778Mointenonce
(5)
Connectthe digitol frequencymeterto monitorihe output fromsignol
generoior (A) .
(6)
Connectthe HF electronic voltmeler(B), high impedonceinput, between
TPI ond chossis(0V).
Adiusimentof L9
(7)
Set signol generoior (A) to o frequencyof 36.2 MHz +50 kHz ond set the
o u i p u tl e v e l t o I . $ y ' e . m . f .
(8)
Tune L9 for o minimumindicoiionon ihe HF electronicvoltmeter(B).
Adiusimeniof L7
(9)
(.|0)
Set signol generotor(A) to o frequencyof 30.0 MHz +20 k1z.
Tune L7 for o moximumindicofionon the HF electronicvoltmeter(B).
Signol level check
(l I )
Set signol generotor (A) to o frequencyof 20 MHz +l MHz.
indicotedon the HF elecironic voltmeter(B).
(12)
Sweepthe frequencyof signol generotor(A) from 35.4 to 65 MHz. Check
ihot the HF electronicvolimeter(B) indicotionis not les thon 20 dB below
the level notedot step (l l).
Note the level
A d i u s i m e not f L l 5 , L l 6 , L l 7 , L I B o n d L l 9
(13)
Disconnecfthe HF electronicvoltmeter(B)from TPI.
(14)
Disconnectthe RFoutput BNC plug from ihe chossismountedfirst mixer input
connector(seeFigure20.5) .
(15)
Connectthe woveformonolyserto the RFoutput BNC plug.
(16)
Set signol generqtor (A) to o frequencyof 35.52 MHz +20 kHz. Tune the
woveformonolyserto this signol, odiustingits ottenuotor, os necessory,to
obtoin moximumsensitiviiy.
(17)
Tune inductorLl7 for o minimumindicotionon the woveformonolyser.
23-36
RA. l77B Mointenonce
(18)
5et signolgenerotor(A) to the following frequenciesin turn. Repeotsteps
(16) ond (17), in eoch coseiuning the opproprioieinductorsfor o minimum
indicotionon ihe woveformonolyser.
Frequency
Inductor
36.88MHz +50kHz
40.74 MHz+SOkn.
Ll8
Ll6
(19)
Disconnectihe woveformonol;,serond connectin its ploce the HF electronic
voltmeier (B), 75O input impedonce.
(20)
Set the frequencyof signol generotor(A) io 30 MHz +20 kHz ond the output
levelto 10mVe.m.f.
(21)
Tune inductorsLI5 ond Ll9 for o moximumindicotionon the HF electronic
voltmeter(B).
(22)
Repeotsieps(15) ro (21) inclusive,
Signol levels check
(23)
Sei the frequencyof signol generotor (A) io I MHz. Note the level
indicotedon the HF elecironicvoltmeter(B).
(24)
Sweepihe frequencyof signol generotor (A) from I to 30 MHz. Ensurethot
the output level remoinswithin 2.5 dB of the level notedot step (23).
(25)
Set signol generotor(A) to o frequency of 30 MHz ond on output level of
r.u mv e.m.l,
(26)
Disconnectihe HF electronicvoltmeter(B) from the RFoutput BNC plug
ond connect in its ploce the woveform onolyser.
(24
Set the woveformonolyserfor moximumsensiiivity ond tune it to the
frequency of signol generotor(A). ,Adiustthe wqveformonolyrer ottenuotor
to obtoin o convenientreference level on the meter. Note the ottenuotor
setting.
(28)
Set signol generotor(A) to o frequency of 35.4 MHz ond on output level
o f l . 0 V e . m ,f .
Q9)
Tune the woveformonolyserto the frequencyof signol generotor(A) ond set
the woveformonolyserottenuqtor to obtqin the reference level set ot step
(27). Note the new settingof the ottenuotor, Ensurethot the differencein
ihe ottenuotorsetting is not lessthon 25 dB.
23'st
RA. l77B Moinienonce
(30)
'
repeotstep-(29)
5et the frequencyof signol generoror(A) to.70 YHt :id
dB'
is not lessthon 25
Ensurethoi the differencein ott"n'oto' seitings
onolyser'
( 3 1 ) Disconneclsignol generotor(A) ond the woveform
(32)
(A) sei io o level of lO mV e'm'f"
Connectthe output of signolgenerotor
(B)' Note the level os
to ihe 75Q input of the HF liectronic volimeter
indicotedontheHFeIecironicvoItmeter(B)osoreferenceIeveI.
(33) Disconnectsignol generolor(A) fromthe HF elecironic
voltmeter(B) ond
reconnectit to RF input socketon the RFboord'
(34) C o n n e c t i h e H F e | e c i r o n i c v o l t m e t e r ( B ) t o t h e R F o u t p u t B N C p | u g .
in turn' ond check
(35) Sei signol generotor(A) to the following frequencies'
ihoi ihe output level, in eoch cose, is os stoted'
Frequency(MHz)
Ortpril"u"l relotive to ihe
reference level (dB)
0.015
0.100
1.000
2 .000
4.000
8,000
16 . 0 0 0
30.000
+ 5 . 0+ l . 0
+l 1.0-+2.0
+ll.0 +2.0
+ 11 . 0D . 0
+il .0 T2.0
+ll.o D.0
+ l l . O+ 2 . 0
+ ' Il . 0 + 2 . 0
Adiustmentof Ll0
(36)
(A) to 2'2 MHz ond set the output level
Set ihe frequency of signol generotor
t o 1 0 0m V e . m . f .
(37) Set the receiverMHz digiis io 0 monuolly'
electronic
(38) Tune induciorLl0 for o minimumindicotionon the HF
voltmeter(B).
Signol levels check
(3e)
(A) io lO0 kHz' Ensureihot the
Set the frequencyof signol generoior
volimeter' is +15 dB + I dB
, *'indi"o-t"d olnthe HF electronic
"riprif "t"'f
Note ihe output level'
relotive io the signolgenerotoroutput level'
23-38
RA. l77B Mointenonce
(40)
Sweepihe frequencyof signol generotor(A) from 50 kHz io I MHz' Ensure
ihot ihe output level remoinswithin I dB over the frequencyronge'
(41)
Sweepthe frequencyof signol generotor(A) from 2 to 6 MHz ' Ensureihot
the ottenuotionover the bond, with resPectto ihe output level notedot
step (39), is noi lessihon 27 dB'
(42)
Set the CHANNEL switchio I ,
Adiustmentof T5, C28 ond C38
(43)
Ser rhe iuning copociror (c22/C23) control spindle fully counter clockwise
(copociiorsfully enmeshed)
.
(44)
Corefully turn the tuning copocitorspindleclockwiseuntil the microswitch,
SA, operotes. Check thot^thevorioble copocitor is out of meshby exoctly
6 mm, This is equol to l8o of rotolion from the fully enmeshedreference
point (seeFigure23. 1)'
(45)
Set signol generotor(A) to o frequencyof 0.98 MHz ond set the output
l e v e l t o 1 0 0m V e . m , f .
(46)
Tune the cores of T5 for moximumoutput, os indicoted on the HF electronic
voltmeier (B). Ensurethot the top ond bottom cores of T5 ore neor to the
top ond bottom ends respeciivelyof the windings.
(421
Set signol generqlor (A) to o frequencyof 2.0 MHz.
(48)
Adiust rhe runing copociror (c22/C23) for o moximumindicotion on the HF
electronic voltmeter(B).
(49)
Tune trimmer copocitor C28 ond C38 for o moximumoutput indicotion'
(50)
Repeotsteps (9
be obtoined.
to (49) inclusive until no further increcsein oulput con
Signol levels check
(51)
Set ihe tuning copocilorfully counter-clockwise.
(52)
Set signol generdtor(A) to o frequencyof 1.0 MHz. Note the output level
indicotedon the HF electronicvoltmeter(B).
23-39
RA. l77BMointenonce
(53)
Sei the tuning copocitorfor o moximumoutputindicotion. Ensurethot ihe
ouiput level indicotedis wiihin 6 dB of the level notedoi siep (52)
(54)
Set the frequencyof signol generotor(A) to I MHz +125 k1z ond, in turn,
to I MHz -125 kHz. Ensureihot ihe ottenuotion,in eoch cose, is not less
ihon 16 dB reloiive to the level qi I MHz.
(55)
Set the frequencyof signol generotor (A) to 2 MHz.
(56)
Set the tuning copocitorfully counter-c lockwiseond note ihe outpui level
indicoted.
6n
Sei lhe tuningcopocitorfor o moximumouiput indicotion. Ensureihqi the
level indicotedis within 6 dB of the level noted ot step (56).
(58)
Ensurethoi fhe ottenuotion 250 k1z &ove ond below 2 MHz is not lessthon
16 dB relotive to the output level ot 2 MHz,
Adiustmentof remoiningtronsformersond trimmer copociiors
(59)
2
4
8
16
)
Repeotthe proceduresfrom step (43) to step (58) inclusive for the remoining
tronsformers
ond lrimmercopocitorsin occordoncewiih ihe following toble:-
MHz
Signol
Switch GenerSetting otor
MHz
Tronsformer
2
4
4
8
B
16
16
30
T4
T3
T2
Tl
-
Copocitor
C2h<37
C261<36
C25+C35
c24-+C34
Output dB
Reloiiveto
Step (52)
W i t h i n6 . 0
W i t h i n6 . 0
w i t h i n6 . 0
Within6.0
w i r h i n6 . 0
Wiihin6.0
Wirhin
6.0
Wirhin6.0
Attenuoiion
oi
MHz
+O.25
rO.S
T{.5
+l
;-+2
l
i2
13.75
Not less
thon -dB
16
16
17
17
17
17
17
17
ProtectionStoge
66.
(l)
Disconnectsignol generotor(A) from ihe RF input connectorond substiiute
the high powersignolgenerotor(B).
Adiustmentof C33
(2)
Connectihe multimeter,set to the 2$/ d.c, ronge, betweenthe collector
(0V).
ofTRB (posiiive)ond chcrssis
23-40
RA. |778 Mointenonce
]
(3)
Connectthe HF electronicvoltmeter(A) to TP2.
(4)
Set C3l to moximumcopocity.
(5)
Set the frequencyof signol generotor (B) to 30 MHz ond set the output level
for o HF electronicvoltmeier (A) indicotionof 2.0V.
(6)
Adiust C33 until ihe multimeterindicotion chongesfrom opproximotelylV
to +l2V .
@
Reducethe output level fromsignol generotor(B)to lV e.m.f. Checkthot
fhe indicotionon the HF electronic voltmeter(A) is opproximotely0.5V.
(B)
Slowly increosethe output level from signol generoior (B) until the volve
voltmeierindicotionfolls to zero. Ensurethot the signol generoioroutput
l e v e l i s b e t w e e n2 . 5 o n d4 . 0 V e . m , f .
Adiusrmentof C3l
(9)
Connectthe multimeter,set io the 25V d. c. ronge, betweenthe collector
of TR3 (positive) ond chossis(0V).
(10)
Connectthe HF electronicvoltmeter(A) to TPI,
(l l)
Set the output level of signol generotor (B) for o HF electronic voltmeter (A)
indicotionof 4.0V.
(12)
Adiust C3l uniil the multimeter indicotion chorgesfrom opproximotely lV
to +l2V .
(13)
Reducethe output level from signol generotor(B)to lV e,m.f. Check thot
the indicotionon the HF electronic voltmeter(A) is opproximotely0.5V.
(14)
Slowly increosethe output level from signol generotor(B) until the HF
electronicvollmeter(A) indicotion folls to zero. Ensurethot the signol
generotoroutput level is between7 ond l4V e.m.f.
(15)
Disconnectthe multimeier,
23-41
RA. 1778Mointenonce
Muie Circuit
67
(l)
Set the outpui level of signolgenerotor(B) to lV e.m'f '
(2\
Ensurethot the indicotion on the HF electronic voltmeter (A) (conneciedto
TPI) is opproximoiely0.5V.
(3)
connect o wire link betweenthe MUTEond E terminolsof TS2. Ensureihot
the HF elecfronicvolimeter(A) indicotionfolls to zero'
(4)
Removethe wire link from ihe MUTE terminol ond ensurethot ihe HF
electronicvolimeter(A) ogoin indicotesopproximotely0,5V.
(5)
Switchoff ond disconnecioll test equipment'
(6)
Replocethe cooxiol RF output connecfedio the chossismountedfirst mixer
input connector
I
68.
Deleted
PM364
IFIAFBOARD(S)
PROCED(RE
FINALSETTING-UP
TestEquiprnenf
69.
(l)
- B(B)
Sisnolgeneroior
(2)
Outpui PowerMeter - 8(l l)
(3)
HFelectronicvoltmeter(B)- B(5).
(4)
Digitol frequencYmeter- B(7)
(5)
Multimeter- 8(3).
Reference
70.
(l)
C h o p t e1r 2 .
(2)
Chopter24, FigvrePM364.lond PM364.2
23-42
RA.I77BMoinienonce
AP 1l6E-0754-68
MAtN tFlAF BOARDPM364ll
Proc ed ure
71.
(l)
Connectthe outputof ihe signol generotor(poroB, item g) to the
receiver ontennosocket.
(2)
Connect ihe wotimeterobsorption, set to the B-ohm ronge, between
f h e L So n d E t e r m i n o l os f T S l .
(3)
Set the frequencyof the signol generotorto l.02MHz ond set the
o u l p u tl e v e l t o I m i c r o v o l fe . m . f .
(4)
Ser rhe AGC switchio OFF, rhe MODE swirchro USB,the USB
BANDWIDTHswitchto 3 ond the lF GAIN control fully clockwise.
(5)
Usingthe HF electronicv.:limeier, high-impedonceinput, monitor
TP3ond odiustR9 for on indicotion of 200 millivolts r. m. s.
(6)
Connect the multimeter, set io the 5V DC ronge, betweenboord pin
29 (positive)ond chossis. Check thot the multimeterindicotes1.4
.|50
volts plusor minus
millivolts.
(7)
Disconnectthe muliimeterond the HF electronicvoltmeter.
(8)
Set the AGC swirchro SHORTond ser rhe AF GAIN control fullv
clockwise. Check thot the wottmeterindicqiion is greoterthon i wqtt.
(9)
Set the AF GAIN control for on indicorionof 100 milliworfson the
wottmeter.
(10)
set the AGC switchto oFF ond set the lF GAIN control to restorethe
woltmeterindicotionto 100 milliwotts.
(l l)
Detunethe signolgenerotorby ot leost l0kHz ond check thot the signolplus-noise-to-noise
rotio exceedsl5dB.
(12)
Retunethe signolgenerotorto the receiver.
(13)
Tronsferthe wottmeter,set to the 600 ohmsronge, io the LINE OUTPUI
M A I N l F t e r m i n o los f T S I .
(14)
Set the fronr-ponelMETERswiich ro A^VUSB.
(15)
Adiust the AA4/USBLINE LEVELcontrol for on ourpurof I milliwotr on
the froni-ponelmeter. check thot the wottmeterindicotionis I milliwott
p l u so r m i n u sI d B .
23-43
RA.l77B Mo intenonce
AP I r6E-0754-68
Jon.82 (Amdt3)
-
F
71A.
(16)
Set the AGC switch to SHORT.
(17)
Increosethe output level of the signolgenerotor,in ldB steps,until
the AGC knee is reoched, i.e. whereo further increosein the signol
generotoroutput level doesnot result in on increosein oudio power
output. Ensurethot fhe signolgenerotoroutPutlevel is lessthon I '7
m ic r o v ol t s e . m ' f .
:
(lB)
Set the signol generotoroutpuf level 2 microvoltse.m.f.
(19)
Adiust the A^VUSB LINE LEVELcontrol for o convenientreference
level on the wottmeter.
(20)
Increosethe output level of the signolgenerotorby l00dB obove
2 microvolts.
(21)
Ensurethot the increose in the output power level is not greoter thon 5dB
,)
relotive to the reference level estoblishedot operotion (19)'
,)a
(22)
Set the AGC swiich to LONG ond repeotoperotions(18) to (21)
inclusive .
(2!
Set the AGC switch to SHORTond the METERswitch to RF.
(24)
Sei the signol generotoroutput level to 2 microvoltse.m'f '
(25)
Tune the signol generoior to lhe receiver.
(26)
AdiustR17, on the meterswitchingboord, for on indicotion of OdBon
the froni-ponel meier.
(27)
Increoseihe output level of the signol generotorby l00dB obove
2 microvolts.
(28)
Adiusf Rl4 on the meter switchingboqrdfor on indicotionof i00dBon the
front-ponelmeter.
(29)
Repeoloperotions(24) io (28) for optimumresults'
Corry out the procedurein poro.79'
{
23-44
RA..1778Mointenonce
)
(PM364l3)
I sBltFIAFBOARp
hocedure
72,
(l)
Connect the oufput of the signol generotor(poro 8, item g) to the
receiverontennosocket.
\2)
Conneci ihe wotlmeier obsorption,set lo the B ohmsronge, befween
the LSond E terminolsof TSl.
(3)
Set the frequencyof the signol generotorto l.02MHz cnd set the
output level io I microvolte.m.f.
(4)
Set the AGC swirchro OFF, the MODE swirchro ISB-Lond rhe lF
GAIN control fully clockwise.
(5)
Usingthe HF electronic voltmeter, high impedonceinput, monitor
TP3ond odiustR9 for on indicotionof 200 millivolts r.m.s.
(6)
Connect the multimeter, sei to the 5V DC ronge, between boord pin 29
(posiiive)ond chossis. Checkthot ihe multimeterindicotes1.4 volts
p l u so r m i n u s1 5 0m i l l i v o l t s .
v)
Disconnectthe muliimeterond the HF electronicvoltmeter.
(8)
Set the AGC switch to SHORTond ser rhe AF GAIN conrrol fully
clockwise, Check thot the wottmeler indicotion is greoter fhon I wqtt.
(e)
Set the AF GAIN control for on indicotion of 100milliwottson the
wqltmefer.
( 1 0 ) Set the AGC switch to OFF ond set the lF GAIN control to restorefhe
wottmeterindicotionto 100milliwoits.
(lt)
Detune the signol generotorby ot leost lOkHz ond ensurethot the signolplus-noise-to-noise rotio exceedsl5dB.
(12)
Retunethe signol generoior to the receiver,
( 1 3 ) Tronsferthe wottmeter, set to the 600-ohm ronge, to the ISB LINE
OUTPUI terminolsof TSI .
( 1 4 ) Set the front-ponel METERswitch to LSB.
( 1 5 ) Adiust the LSBLINE LEVELcontrol for on output of I milliwqtt on the
front-ponel meter. Check thot the wottmeter indicotion is I mill iwott
plusor minus ldB.
23-45
RA,1778A4o
intenonce
(16)
Set ihe AGC swirchro SHORT.
(17)
Increosethe outputof the signolgenerotor,in IdB sleps,until the AGC
knee is reoched, i.e. whereo further increosein the signolgenerotor
outpui level doesnot result in on increosein oudio poweroutput' Ensure
thot the signol generotoroutPutlevel is lessthon 1.7 microvoltse'm'f '
(lS)
Sei the signolgeneroloroutput level to 2 microvoltse.m.f .
(19)
Ad[ust the LSBLINE LEVELcontrol for o convenientreferencelevel on
ihe wottmeter.
(20)
Increqsethe output level of the signol generotorby l00dB obove
2 microvolts.
(2.|)
Check thot ihe increosein the output level is not greoier thon 5dB
relotive to the reference level estoblishedot operotion (19).
(22)
Set the AGC switch to LONG ond repeot operotions(18) to (21)
inclusive.
SWITCHES
MODEAND FILTER
73.
(1)
Connect the output Powermeier, set to the BQ ronge, betweenthe LS
ond E terminolsof TSI .
(2)
Set the receivercontrol os follows:MHz
3
020.00
kHz
TUNINGMTE LOCK
R FT U N E
AGC
AFC(if fiiled)
lF GAIN
LS
WB
SHORT
oFF
Fullyclockwise
ON
(3)
Connectthe outputof the signolgenerotorto the receiverontennosocket.
Setthe signolgenerotorfrequencyto 3 MHz ond set the outputlevel to
l O u Ve . m . f .
(4)
Setihe MODEswitchto LSBond, in turn, to ISB-Lif fitted. Tunefhe
signolgenerotorfrom3.00 to 3.05 MHz on eochmode. Ensurethof ot
whichreducesin pitch
3.02 MHz o highnote is heordin the loudspeoker
to zero beotond then disopPeors.
23-#
RA.l778 Mointenonce
(5)
Set the MODE switch to USBond,in turn, to ISB-Uif fifted. Tunethe
signol generotorfrom3.05 to 3.00 MHz on eoch mode. Ensurethot ot
3,02 MHz o high note is hecrd in the loudspeoker
which reducesin pitch
io zero beot ond then disoppeors,
(6)
Sei the MODE switch io CW,
(7)
Turn the receiver onto its side ond connect ihe digitol frequencymeter
between pins I I ond 32 (0V) on the 34 MHz generotorboord PM339.
(8)
Set the front ponel BFO control to -.
(e)
Adiust L4 on the 34 MHz generotorboord until the frequency disployedon
the digifol frequencymeteris 1.396 500 MHz +100 Hz.
( 1 0 ) Set the BFO control to +.
(l r)
Adiust R4 on the 34 MHz generotorboqrd until the frequencydisployedon
ihe digitol frequencyis I,403 500 MHz +100 Hz.
(12) Repeotsteps(B) to (l l) inclusive until no further improvementcon be
obtoined.
(13)
Disconnectthe digitol frequencymeter ond turn the receiver onto its bose.
(14)
Connect the digitol frequencymeter to the UNCAL socket on the signol
generotor (omit if MCAL gbl /62 signol generotoris used).
(15)
Set the frequencyof the signolgenerotorto 3.020 00 MHz ond moinioin
if ot this frequency.
(16)
Set the BFO control to 0.
(17)
Set the output level of the signol generotorto I pV e.m.f.
(18)
Set the FILTERswitch to the widestbondwidth.
(19)
Adiust the BFO control for o convenient fone in the loudspeoker,
(20)
Set the FILTERswitch to eoch position, in turn, cnd ensurethot there is no
chonge in the level of the tone ond thot the noise level decreosesos the
bondwidth is decreosed.
(21)
Resetthe FILTERswitch to the widest bondwidrh.
23-47
RA. I 778 Mointenonce
(22)
Tunethe signol generotorfrom3.00 to 3.05 MHz. Ensurethot o high note
which reducesin pitch to zero beot ot 3'02 MHz
is heordin the loudspeoker
qnd fhen risesogoin to o high note.
(23)
Set ihe MODE swiich to AM.
(24)
Set the signol generotorfor 30/o omplitudemodulotionot 400 Hz.
(25)
Tune the signol generoior to the receiver ond ensurethot o 400 Hz tone con
be heord in ihe loudspeoker,
(26)
Swifch off ond disconnectoll tesi equipment.
\
AFC BOARD PM664
Tesi Equipment
73,
(l)
Signolgenerotor- B(B).
(2)
HF electronic voltmeter(B) - B(5),
(3)
Digitol voltmeter- 8(l).
(4)
Output powermeter- 8(l l).
j
References
74.
(l)
C h o p t e1r 7 .
(2)
Chopter24, FisurePM664.l qndPM664.2.
Procedure
75.
0)
Setthe receivercontrolsosfollows:-
RFTUNE
AGC
MODE
MHz
kHz
POWER
FI L T E R
AFC
METER
WB
SHORT
cw
0l
020.00
ON
Widestovoiloble
OFF
TUNECARRIER
23-48
RA. lZ8 Mointenonce
Q)
Removethe bookcoe cover ond slondthe AFC boordverticolly.
(3)
Unsolderthe cooxiol leod connectedto pin 16, leoving the screenconnected
to pin 15.
Adiustmentof C35
(4)
Connecfthe digitol voltmeterbetweenTPlT ond eorth' Adiust C35 for o
reodingof 7.0V !0.1V. Ensurethoi the digitol voltmeierreodingchonges
os C35 is odiusted.
(5)
Meosurethe voltoge betweenTPlT ond TPIB with the digitol voltmeterond
ensurethot the reoding is lessthon 50 mV.
Adiustmentof R29
(6)
os follows:Set the poteniiometers
R5
R34
R37
R4l
R45
(7)
fully clockwise
mid position
fully clockwise
fully counter-c lockwise
fully clockwise
Connectthe electronicvoltmeterto TP4set to 3V o.c. ronge. AdiustM9
for o minimumreoding, increosingthe sensitivityof the electronicvoltmeter os necessory.
Adiustmentof L4 ond R34
(8)
Set the electronic voltmeter, connectedto TP4, to the 1V ronge. Connect
the signol generotorto pin 16.
(9)
Set the frequency of the signol generotorto
output level of 60 pV p. d.
(10)
,|.400
MHz, +20 Hz ond on
Connect o tempororylink between pin l4 ond eorth. Adiust L4 for o
moximumindicotion on the electronic voltmeter crrd ihen set R34for on
indicotionof 800 mV +100 mV. Removethe temPororylink from pin 14.
Adiustmentof R5
(ll)
lncreosethe signol generotoroutput level to 90pV p.d. Adiust R5 in o
directionuntil the signol level ot TP4 os indicotedon ihe
counter-clockwise
by I dB'
electronicvoltmeter,decreoses
23-49
RA. l77BMointenonce
(12)
(13)
Increosethe signolgenerotoroutput level by 3 dB ond note the electronic
voltmeterindicotion.
]
lncreosethe signolgeneroioroutput level by 60 dB' Ensurethot the increose
in the level oi TP4doesnot increcceby morethon 3.5 dB obovefhe
indicotionnoted in step (12).
Adiustmentof Tl
(14)
Connectthe elecironicvoltmeierto TP5ond odiustTl for o moximum
indicotionon the electronicvolimeter. lgnoreony slow beot of the meter
needle,
(15)
Observe the tuning meter ond ensureihot o beot is seenthot is equol io the
differencebetweenihe input signol ond 1.400 MHz.
Adiustmentof R37, R4l
(16)
Reconnectthe cooxiol leod to pin 16. Connecithe signolgenerotorto the
receiverontennosocket. Sei ihe output level to lopV e'm'f. ond tune
it to the receiver possbond.
(17)
Meqsureond note the AGC voltoge ot pin 4 of the AFC boord using lhe
digitol voltmeter.
(lB)
lncreosethe signolgenerororoutput by 30 dB (i.e. io 300pV e.m.f.).
Meosureond note the AGC voltoge ot pin 4 of the AFC bocrd.
(19)
Time the signolgenerolorfor zero beot on the time corriermeter' Switch
ond ensurelock lomp illuminotesofter o few seconds.
AFC to FULLCARRIER
Set the signolgenerotorouiPutto I mV e,m.f.
(20)
Meosurethe voltoge oi TP2on the AFC boord using the digitol voltmeter.
Adiust R4l until the voltoge is within l0 mV of thot noted in (22).
(21)
Reducethe signolgenerotoroutput by 30 dB (i .e. to 30pV e.m.f.).
Adiust R37until the voltogeot TP2 is within l0 mV of thot noted in (17).
(22)
Repeot(20) ond (21) until no furlher improvementcon be obtoined.
(23)
Switch AFC to OFF. Set the signol generotorlevel to I0pV e.m.f.
Switch MODE to USBond tune the signol generoior to the receiver possbond.
Meosureond note the volioge on the DIV AGC terminol on ihe reor ponel
with the digitol voltmeter.
23-50
RA. l77B Mointenonce
i
(24)
Switch MODE to CW, BANDWIDTHto 3 kHz. Tuneihe signol generotor
for zero beot on the tune corrier meter. Switch ihe AFC to PULLCARRIER
ond ensureLOCK LAMP illuminqtesofter o few seconds' Increosethe
signol generotoroutput until the volioge on ihe DIV AGC terminol is the
someos thot notedin (23). Noie ihe increcaein signolgeneroioroutPut
level which shouldbe l0 dB +5 dB. lf this is incorrectrepeotsteps(16)
to (24).
Q5)
Switch AFC to OFF, MODE to USB. Repeot(23) ond (24) for o signol
generotoroutput of 300 yV e.m.f,
Adiustmentof R45
(26)
Switch AFC to OFF. Tune the signol generotor for zero beot on tune corrier
meter, Set the output level to 2 ;,,Ve.m. f , SwitchAFC to FULLCARRIER
ond ensurethqt the LOCK LAMP illuminqtesofter o few seconds. Adiust
R45 unii I the LOCK LAMPstoristo fli cker,
(27)
EnsureLOCK lomp is definitely ON ot 3 pV e.m.f. input.
F5KBOARDPM36B
TestEquipment
76 .
(l)
Signol generotor- 8(B),
(2)
Digitol frequencymeter- 8(7).
(3)
Oscilloscope- B(2).
(4)
Step ortenuoior- B(12).
References
77
(l)
C h o p t e)r8 .
(2)
Chopter24, FisvrePM368.l.
Procedure
78.
(l)
Connect the signol generotoroutput to the receiver ontennosocket, vio
o 50O step ottenuotor.
(2)
Monitor the output of the signol generotorwith the digitol frequencymeter.
23-51.
RA. I 778 Mointenonce
(3)
Set the signol generotoroutputfrequencyio 3.50000MHz ond level to
I0 mV e.m.f.
(4)
Set the receivercontrolsos follows:R FT U N E
AFC (if fifted)
AGC
MODE
FILTER
FREQUENCY
(5)
.\
'
WB
oFF
SHORT
F S KT U N E
I kHz
3.50000MHz
Roisethe FSK boord to the uprighi position ond secure.
Adiustmeniof Ll ond L2
(6)
Connectfhe oscilloscopeto pin lB on the FSKboord.
(7)
Set the step ottenuotor for on oscilloscopedisploy of 200 mV p-p +10 mV.
(8)
Connectthe oscilloscopeto TPI;
(9)
Tune inductorsLl ond L2 in turn for moximumoutput, qs disployed on the
oscilloscope,
1
Adiusimentof Cl7
(10)
Useo T connectorto connectthe digitol frequencymeterond the oscilloscopeio TP2. Check thot the omplitudeof the squorewove disployedis
not lessthon 2.5V p-p.
(l l)
Adiust trimmercopocitorCl7 for on indicotionon the digitol frequency
meter of I 398 000 Hz +1 Hz.
(12)
Disconnectihe digitol frequencymeterond the oscilloscope.
(13)
Set the 6V/B0V ond N+/P/N- switcheson the reor ponel of the receiver to
6V ond P respectively.
(14)
Set the receiverMODE switchto FSK-N.
(15)
Connectthe oscilloscopeio pin 6 on the FSK boord.
(16)
Ensurethot the signol generotoroutput is 3.50000MHz +5 Hz.
ZJ-JZ
RA. 1778Mointenonce
AP I l6E-0754-68
Jon.82 (Amdt 3)
p
(17)
Connecto multimeterbetweenihe +2.1V line (Dl +ve) ond pin 3 of MLI0.
Set the multimeterto its mostselectived.c. volfoge ronge,
(lB)
Adiust R45 until the multimeierreodszero volis.
FINALSETTING-UP
PROCEDURE,
SECONDMIXERBOARD
79.
@"..Thisprocedureiscorriedoutfol|owingporo'7l.
lhe purposeoi the procedureis to restorethe performonceon in-bond
intermodulofionProducts. Unlessotherwisestoted, fest-equiprnentconnectionsremoin os in
poro.Tl .
(l)
Sef RBon the secondmixer boord to the fully clockwise position.
(2)
Connect the h.f. electronic voltmeter to TP3on lhe moin IF/AF boord,
(3)
Check fhot the signol generotoris still set to L02MHz, ond set fhe oufput
level to 300 microvoltse.m.f .
(4)
Tune thi generotor to the receiver ond note the indicotion on the h.f .
voltmeter.
(5)
Set rhe AGC swirchro OFFond odiusrthe lF GAIN control in orderro
restorethe voltmeterreodingto the level noted in operotion(4).
(6)
AdiustR8to reducethe h.f. volrmeter
reodingby IdB.
23-53
RA"1778Mointenonce
AP I t6E-0754-68
Jon.82(Amdt3)
D
Pl\/674l/l
^/ArN IFAF BOARD
80.
(l)
Signolsenerotor - 8(8),
(2)
Digitol voltmeter - 8(l).
(3)
Digitol frequencymeter - 8(7)
(4)
HF elecironicvolimeter(B) - 8(5).
(5)
LF electronicvoltmeter - 8(6).
(6)
Ouiput power meter - B(I I ) .
(7)
Multimeter - B(3).
(8)
R e s i s t o rl ,k , 5 % 0 . 2 5 W - B ( 1 5 ')
Procedure
NOTT:
IMPORTANT
Ihe following olignment proceduresore corried out with the moin IF/AF boord
isoloted from the remoinderof the receiver. Furtherminor odiustmenisore fherefore
requiredfollowing fhe olignmenfof the RF, first mixer ond secondmixer boords.
Theseodiustmentsore given in poro.98.
81 .
(l)
Set the receiver front-ponel controls os follows:(o)
(b)
(")
(d)
(.)
RF TUNEto WB.
AGC to OFF ond AFC to OFF.
.
lF GAIN fully counter-clockwise
MODE to USBond USBBANDWIDTHio 3.
AF GAIN fully counter-clockwise.
(2)
Unsolderihe cooxiol leod connectedto pin 2 on fhe filter boord PS367
(the cooxiolscreenmoy be left conneciedto pin 3).
(3)
Connect the I kQ resistorin serieswifh the cooxiol leod connectedto the
50 ohmoutputof the signol genemtorond connectthe other end of this
leod to the cooxiol leod removedot step (2). Connectthe screento pin 3
on the filter boord.
23-54
RA.l778 Moinlenonce
{
AP I l6E-0754-68
Jon.82 (Amdt3)
F
(4)
Connectthe digitol frequencymeterto the UNCAL socketon the signol
genersfor,
(5)
Set the frequencyof the signol generotor io I .400 MHz, + 500 Hz ond the
output level to 60 p e.m.f . - a ;-ai,n'
(6)
Set the lF GA lN
(7)
Ensurethot the MODE switch is set to USB.
(B)
Ensuretho t theAF GAIN control is set fully counter-clockwise
,
(9)
Set oll potentiomeiers(Rl, R6, R7, R9, R23, R45, R55)fully clockwise.
control fully clockwise.
Ad[ustmentof Ll , L2 ond Rl
82.
(l )
Connectihe HF electronicvoltmeier, high impedonceinpui, to TP3,
(2)
Adiust inducton Ll ond L2 for o moximumindicotion on the HF electronic
voltmeter.
(3)
Adiust R1 for o level of 200mVot TP3ond then repeot step (2).
(4)
Sweepthe signolgenerotorfrequencyfrom I390 kHz to l410 kHz. Note
the freguencyot which the peok output occun. Also note the level of the
peok ouiput.
(5)
Sweepthe signol generotorfrequencyogoin from 1390 kHz to l4l0 kHz.
'l
Ensurethot ihe output level remoinswithin dB of the level noted ot
step (4) .
(5)
Set the signol generoiorto the frequency noied ot step (4).
(7)
Adiust Rl for on indicotionof 200 mV r.m.s. on the HF elecfronic
voltmeter (connectedto TP3).
(8)
Repeotsteps(4) orid (5), lf the I dB toleronce of step (5) connot be met
repeot steps(2) to (7),
23-55
RA.l77B Mointenonce
a
AP I l6E-0754-68
Jon.82(Amdt3)
83.
(l)
Connectthe digitol voltnreierto boordpins 29 (posilive)ond 28 (0V)'
(2)
Adiust R45for on indicotionof I '4V +25mVon the digitol voltmeter'
Adiusimentof R55
84.
(1)
Reducethe signolgenerotoroufPutlevel by 4 dB.
(2)
Connectthe multimeter,set to the 25V d.c. ronge, betweenTP6 (positive)
ond ihe -7V supplyot boordPin 20.
(3)
Adiust R55until the indicotionon the multimeterchongesfromposiiive
l 4 V + l V t o p o s i t i v e7 V r 2 V '
(4)
Reducethe signol generotorouiPut level by o further ldB ond ensurethot
the originol multimeterreoding(+l4V + lV) is restored.
Adiustmentof R9
85.
(l)
Resetthe signolgenerotoroutput level to 60 p V e.m.f . Ser the AGC
switchto LONG.
(2)
the signol genemtoroutput level by 65 dB ond noie the reodingon
Increose
the HF electronicvoltmeter(connectedto TP3).
(3)
Adiust R9 for o 2 dB increosein the reodingof step (2).
Adiustmentof R6ond R7
86.
(l )
Set the AGC switch to SHORTqnd the signol generutoroutpui level to
l.lmVe.m.f.
(2)
Adiust R6 for on indicofionof I .7V d.c. *10 mV on the digitol voltmeter
(connectedto Pin 29).
..(3)
Set the signolgenerqtoroutput level to 33.8 mV e.m'f ' (l 'lmV +30 dB)
ond odiustR7 ftr on indicotionof Lg5V d.c. +lOmV on the digitol voltmeter.
(4)
Repeotsteps(l ) to (3) until no further odiustmentis necessory'
{
23-ft
RA.177BMointenonce
AP lr6E-0754-68
Jon.82 (Amdt3)
F
Signol Level Checks
87.
(l)
Connectthe HF electronicvoltmefer,50e input impedonce,to the lvlAlN
IF OUT socketon the reor ponel.
(2)
Ser rhe AGC swirchro SHORT.
(3)
Set the frequencyof the signol generororto 1.400 MHz * 500 Hz ond the
o u t p u tl e v e l t o 6 0 p V e . m . f ,
(4)
Ensurethoi the lF output signol level, os indicotedon the HF electronic
voltmeter, is not lessthon 50 mV r.m,s.
(5)
Increosethe signol generotoroufput level by 62 dB. Ensurethot the
increose in the lF output signol level is not greoter thon 5 dB.
(6)
Resetthe signol genemtoroutput level to 60 p V e.m.f . Ser the AGC
switch to LONG ond repeot steps(4) ond (5) .
(7)
Resetthe signol generotoroutput level to 60 p V e,m,f, ond ensurethot
the lF output is restoredwithin 4 to 8 seconds.
(B)
Connect the LF electronic voltmeter ro boord pins 8 ond 9 (0V).
(9)
Tune the signol generotorfor o moximumindicotion on the LF electronic
volfmeter. Ensurethof the level indicotedis not lessthon 150 mV r.m,s,
(10)
Disconnecithe LF electronic vollnreter. Connect ihe output power meter,
set to 8Q input impedonce, betweenthe LSond E terminols of TSI .
(l 1)
Set the A F GA lN control fully clockwise ond ensurerhot the output power
meterindicotion is nof lessthon I W.
(.l2) Set the AF GAIN controlfor on indicotionof 100 mW on the output power
meler.
(13)
lncreosethe signol generotoroutput level by 62 dB ond ensurethot the output
power rneterindicotion is not greoter thon 100 mW +5 dB.
(14) Reducethe signolgenerotoroutpui level by 52 dB,
(l 5)
Set the MODE swirchro AM.
(16)
Set the signol generolor for 30% omplitude nrodulotionot I kHz.
23-57
RA.1778Mointenonce
AP Il6E-0754-68
Jon.82(Amdt3)
F
(17) Set the AF GAIN control fully clockwiseond ensurethot the output power
meier indicotion is not lessthon I W.
(lB)
Set the AF GAIN control for on indicotion of I W on the outpul power meter'
(.l9) Connecto wire link betweenthe MUTEond E terminolsof TS2. Ensurethot
by not lessthon 40 dB. Disconnect
the output powermeterindicotiondecreoses
the wire I ink.
(20) Set the MODE switchto USB.
(21) Resetthe signol generotoroulPutlevel to 60 ;r V e.m.f.
(22) Tronsferthe output Power meter, set to 600Q inpui impedonce, to the
LINE OUIPUT A A IN lF terminolsof TSI .
(23) Sei the A lv!,/USBLINE LEVELcontrol fully clockwise ond ensurefhor the
Dowermeterindicotionis noi le$sthon l0 mW.
(24) Set the MODE switch to AM.
/r(\
Set ihe signolgenemtorfor 3@/"omplitudemodulotionot I kHz.
(26) lncreosethe signolgenerotoroutput level by 60 dB. Ensurelhot the output
power meterindicotionis not lessthon 4 mW.
(27) Adiusi ihe AM/USB LINE LEVELconirol for on output indicotionof I .0 mW'
(28) Switchoff ond disconnectoll iest equipment.
(2e) Reconnectihe cooxiol leod to pin 2 on the filter boordremovedot step (2) of
p q r o .8 1 .
P^Mt112
tsB/\F/AFBOARD
Tesi Equipment
88.
The itemsof testequipmentrequiredfor the following test ore os lisied for ihe
moin lF/A F boord, poro.79.
IMPORTANTNOTE
ore corriedout with the l5B IFAF boordisolotedfrom
The following olignmentprocedures
ihe renroinderof the receiver. Furtherminor odiustmentsore therefore required following
ore given
ihe olignmentof the RF, first mixerond secondmixer boords. Theseodiustments
in pori.l00.
23-58
RA.l77BMointenonce
{
AP I l6E-0745-68
Jon.82(Amdr3)
D
PreIi minory
8e.
(r)
Set the receiverfroni ponel controlsos follows:-
AFC(if fitted)
MODE
I FG A I N
AFGAIN
OFF
\.,,r I
LSB
Fullyclockwise
Fully counter-clockwise
(2)
Set oll potentiomeiers(Rl, R6, R7, R9, R23, R45, R55)fully clockwise.
(3)
Unsolderthe cooxiol leod connected to pin 4 on the filter boord pS367(the
cooxisl screenmoy be left connected lo pin 5).
(4)
connecl the I kQ resistorin serieswiih the cooxiol leod connected to the
50Q output of fhe signol generolor. Connect fhe other end of this leod ro
lhe cooxiol leod renrovedot step (3). Connect the screento pin 5 on the
fi lter bocird.
(5)
connect the digitol frequencymeterto rhe UNCALsocketon the siqnol
genemtor.
Adiusimentof Ll , L2 ond RI
90'
(l)
set the frequencyof the signorgenerotorr ,400 MHz, + 500 Hz, ond the
outputlevel to 60 p V e.m.f . _114g_,
(2)
Connect the HF electronic voltmeter, high input impedonce, to Tp3,
(3)
Adiust inducton Ll ond L2 for o moximumindicotion on the HF elecfronic
voltmeter.
(4)
Adiust Rl for o level of200 m V r.m.s. ot Tp3ond then repeorstep (3).
(5)
Sweepthe signol generotorfrequency from 1390 kHz to l4l0 kHz. Note
the frequencyot which the peok outpui occurs. Also note the level of the
peok output.
(6)
Sweepthe signol generotorfrequencyogoin from 1390 kHz to l4l0 kHz.
Ensurethot the output level remoinswithin I dB of the level noted ot
srep (5) .
(7)
Set the signol generotorto the frequency noted ol sfep (5).
{
23-59
RA.l778 Mointenonce
AP I I6E-0754-68
hn.82 (Amdt3)
voltmeter (connected to TP3)'
Adiust M3 to reducethe HF electronicvolimeterindicotion to 100 mV
ond then resetthe level to 200 mV with Rl .
-
(9)
'
(tO) Repeotsteps(5) ond (6). lf the I dB toleronce of step (6) connot be met
repeot sieps (3) to (10)
Adiustmentof R45
91.
.
(l )
Connectthe digitol voltmeterto boordpins 29 (positive)ond l8 (0V).
/
(2)
Adiusi R45 for on indicotionof I '4V * l0 mV on the digitol voltmeter,
A .liustmentof R55
92. .,. (1)
"
't
(2)
Connectlhe multimeter,set to the 25V d.c. ronge, betweenTP6 (positive)
ond the -7V supply ot boord pin 20.
(3)
Adiust R55until the indicotionon the multimeterchongesfrom positive
l 4 V * l V t o p o s i t i v e7 V + 2 V .
(4\ " Reducethe signol genemtoroutPutlevel by o further I dB ond ensurethot
the originol muliimeterindicotion (+14V I lV) is restored'
A d i u s t m e not f R 9
93.
:
- Elt-oi:'r'
Reducethe signol generotorou.tPutlevel by 4 dB.
-/
(l)
-
(Z)
,"
(3)
.
_ 1) ) B,-
Resetthe signol generoloroutPui level io 60 p V e.m.f . Set the AGC
swirch ro L.NG.
_ t7a i1,^
Increosethe signol generotoroutput level by 65 dB ond noie ihe reodingo''
the HF electronic voltmeter(connectedto TP3).
Ad[ust R9 to give o 2 dB increosein the reodingon the HF electronic
voltmeter.
Adiustmentof R5ond R7
94. -
(l\
Set the AGC switch io SHORTond the signol generotorouiput level to
1 . 1 m V e . m . f. - S Z a B ^ n
,/
(2)
.
AdiusrR6for on indicotionof I .7V d.c. + lOmVon the digitol voltmeier
(connectedto pin 29).
23-60
MA.1778Mointenonce
AP I l6E_0754_6B
Jon.82(Amdt3)
t"pt
(4)
- 23ae,,,.
S e ti h e s i g n o lg e n e r o t oor u t p u tl e v e l f o 3 3 . 8 m V e . m . f . ( l . I m V + 3 0
dB)
ond odiusi R7 for on indicoiion of L95V d.c. + l0 mV on the digirol
vo linrete r ,
Repeotsteps(l) to (3) uniil no furtherodiustmentis necessory.
Signol Level Checks
95
(l)
Connectthe HF elecironic voltmeter,50e impedonceto the lF OUTsocket
on the reor ponel.
(2)
Set the AGC swirch ro SHORT.
(3)
Set the frequency of the signol generotorto 1.400 MHz, + 500 Hz ond
the output level to 60 u V e.m.f,
(4)
Ensurethot the lF output signol level, os indicotedon the HF electronic
voltmeter, is not lessthon 50 mV r, m.s.
(5)
Jncreosethe.signolgenerotoroutput level by 62 dB, Ensurethof
the
increosein the lF output signol level is not greoierthon 5 dB.
(6)
Reset.ihesignol generotoroutput level to 60 p V e,m.f , Set the AGC
swirch to LONG ond repeot steps(a) ond (5) .
(7)
Resetthe signol generotoroutpui level to 60 p V e,m,f. ond ensure
thot
the lF output is restoredwithin 4 to B seconds.
(B)
Connectthe LF electronicvoltmeterto boordpins B ond 9 (0V).
(9)
Tune the signol generoior for o moximumindicotion on the LF
erectronic
volimeler. Ensurethot the level indicotedis not lessihon .150
mV r,m,s.
(10) Disconnectthe LF elecironic volimeter.
(l I)
output power meter, set to 600e inpur impedonce, to rhe
-C^._"T"lt!.
ISBLINE OLITPLfiierminolsof TSI .
('12) set ihe LSBLINE LEVELcontrol fully clockwiseond ensure
thot the ourput
power meter indicotion is not lessthon 4 mW.
(13) set the LSBLINE LEVELconrrolfor on indicotionof LOmw on rhe
outout
power meter.
23-61
RA,177BMointenonce
{
AP I l6E-0754-68
Jon.82 (Amdt3)
(14) Increosethe signol generotoroutput level 6y 62 dB ond ensurethol ihe
output powermeterindicotion is not greoterfhon I'0 mW +5 dB'
(15) Connectthe LF eleclronic voltmelerocrossthe outPutPowermeter
terminols.
(16) Adiust the LSBLINE LEVELcontrol for on output indicotionof I '0 mW'
07\
connect o wire link betweenthe MUTEond E terminolsof TS2. Ensure
thot the outpui level is reducedby not lessthon 40 dB. Removethe wire
link.
(lB)
Switchoff ond disconnecioll tesi equipment'
the cooxiol leod to pin 4 on the filter boordremovedoi
(19) Reconnect
steP(3) of Poro.89'
(lFlAF boords PM674)
TYPICALSIGML LEVELS
96,
underthe following test
The iypicol signol levels listedbelow were meosured
conditionsunlessstotedotherwise:
(l)
Signolgeneroior,outPul level se! to 40 p V e'm'f ' CW, connectedto
the lf input, pins 34 ond 35 (filter boori output open circuit)'
(2)
Receiverfront ponel conirolssei os follows:-
MODE
Moin IF/AFboord:
ISBlF/AFboord:
IFGAIN
USB
LSB
OFF
fully clockwise
(3)
ot TP2, TP3ond TP4were modeusingthe HF electronic
Meosurements
voltmeter(B), high input impedonce.
(4)
oi 1p7 ond pins 8/9 were mode using the LF electronic
Meosuremenls
voltmeter'
23-62
RA.l77B Mointenonce
.{
AP I l6E_0754_68
Jon. 82 (Amdt3)
IP2
TP3
TP4
IP7
PinsB ond9
TP7
2 0 0m V r . m . s .
2 0 0m V r . m . s . ( s e tb y R l )
B e t w e e9n0 o n d ' 1 3 0m V r . m . s .
Befween
50 ond90 mV r. m. s,
Not lessthon I50 mV, typicolly
b e i w e e n1 7 0o n d2 5 0m V r . m . s .
Signol generolor output increosed
to 120pV, ompliiudemoduloted
30%
ot I kHz: Between
50 ond 90 mV r.m.s.
F I N A LS E T T I N G - UPPR O C E D U R
I FEAF BOARD(S)
PA/674
TestEquipment
97 .
(l )
Signol generoror - B(8).
(2)
Output power merer - g(ll).
(3)
HF electronic voltmeter(B) - B(5).
(4)
Digilol frequencymeter - B(Z).
/5)
Mu lti meter - B(3).
/\,4A
IN IF/AF BOARDPA467
Set the receiver to o frequencyof | 020.00 kHz.
Connecl the output of the signol generotorto the receiverontenno
sockei.
Connect the-output power meter, set to the ge ronge, between
LS ond E
terminoIs of TSI .
(4)
Set the frequency of the signol generotorto I ,02 MHz ond set the
oufput
level to I pVe.m.f. Tunethe signolgeneroiorto the receiver.
Set rhe AGC swirchro OFF, rhe AFC swiich (if fiiled) to OFF, the
MODE
swiich to USBond the lF GAIN control fully clockwise.
(6)
Usingthe HF electronicvoltmeter(B), high impedonceinpui, monitorTp3
ond odiust Rl for on indicotionof 200 mV r. m.s.
(7)
Connect.themultimeler, set io.the 5V d.c. ronge, betweenboord pin 29
(positive)ond chossis. Ensureihoi the multimeterindicotesI .4v +
l50mV.
(B)
Disconnectthe multimeterond the HF electronicvolimeter(B).
n-63
RA ,1778 Mo inienonce
AP I t6E-07s4-68
Jon.82(Amdi3)
(g)
ondsettheAF GAIN controlfully clockwise.
set the AGC swirchto SHORT
Ensurethot the outPutPowermeterindicotionis greoterthon I W'
(.l0)
SettheAF GAIN controlfor on indicotionof 100mWon the outPutPower
meter.
(1I )
Setthe AGC switchto OFFond set the lF GA IN controlio restorethe
outputpowermeterindicotionto 100mW.
(12)
Detunethe signolgenemtorby ot leostl0 kHz ond ensurethot the signol
plus noiseto noiserotio exceeds15dB.
(13)
Retunethe signolgenerotorlo the receiver.
(14)
Tronsferthe outputPowern€ter, set to the 600Qonge, to the LINE
OUTPUTl'/A tN lF terminolsof TSI.
(15)
switchto AI4/USB.
Setthe front.ponelMETER
(16)
Adiust the AAVUSBLINE LEVELcontrolfor on outputof I mW* li: f'-tll
ponel meter. Ensurethot the outputPowermeterindicotionis I mW+ I dB'
(17)
SettheAGC switchto SHORT.
(18)
Increosethe outputlevel of the signolgenemtorin I dB stepsuntil the AGC
kneeis reoched,i.e. whereo furtherincreosein the signolgenerotor
output level doesnot resuliin on increosein oudio poweroutput' Ensure
outPutlevel is lessthon I .7 pV e'm'f'
thot the signolgenerotor
(lf1
Setthe signolgenerotoroutputlevel to 2 pV e.m'f .
(20)
AdiusrrheAM/UsB LINE LEVELcontrolfor o convenientreferencelevel
on the outPutPowermeter'
(21)
lncreosethe output level of the signolgenerotorby 100 dB obove2 pV'
(22)
Ensurethot the increosein the outputpowerlevel is not greoterthon 5 dB
ot step(20)'
relotive to the referencelevel estoblished
(23)
Setthe AGC switchto LONG ond rePeotstePs(19) to (22) inclusive'
(24)
switchto RF,
ond the METER
Setthe AGC switchto SHORT
(25)
outputlevel to 2 pV e.m.f.
Sei the signolgenenoior
(26)
Tunethe signolgenerotorto the receiver.
{
23-64
RA.177BMointenonce
.-
AP Il6E-0754_68
Jon.82 (Amdt3)
>
99,
(27)
Adiust Rl 7 on the meterswitchingboordfor on indicoiion of 0 dB on rhe
front ponel meter.
(28)
Increosethe output lever of the signorgenerotorby 100 dB obove 2;rV.
(29)
Adiust RI4 on the meterswitchingboordfor on indicotion of I00 dB
on the
front ponel meter.
(30)
Repeorsreps(25) to (29) for opfimumresulrs.
corry out fhe pocedures in poro.79. unressofherwisestored, tesf-equiFnent
conditionsremoin os in poro.98,
tsg IF/AFBOARDPt/,b74/2
100.
(l)
Set the receiver fo o frequencyof I 020.00 kHz.
(2)
Connect fhe oulpui of the signol generotorto the receiver ontenno socket,
(3)
Connect the output power meter, set to the Be ronge, befween the LSond
r n e E t e r m r n o l os t l 5 l .
(4)
Set the frequency of the signol genemtor to I ,02 MHz ond set the output
level to I pV e.m.f, Tunethe signolgenerotorto the receiver.
(5)
Ser rhe AGC swirch ro OFF, the AFC swirch (if firied) to OFF, the MODE
switch to ISB-Lond the lF GAIN control fully clockwise.
(6)
Usingthe HF electronic voltmeier(B), high impedonceinput, monitorTp3
ond odiust Rl for on indicotionof 200 mV r.m.s.
(7)
Connectthe mulfimeier,set fo the 5V d.c. mnge betweenboordpin 29
(positive)ond chossis. Ensurefhot ihe multimeterindicotesI .4v + 150 rhv.
(8)
Disconnectthe muliimeterond the HF electronicvoltmeter(B),
(e)
set the AGC switch to sHoRT ond set rhe AF GA lN control fullv clockwise.
Ensurethot the output powermeterindicotion is greoterthon I W.
( 1 0 ) Set the AF GAIN control for on indicotion of 100 mW on the output oower
meTer.
(lI)
Sei the AGC switch to OFF ond set the lF GA lN control to restorethe
output power meier indicotion to 100 mW.
( 1 2 ) Detunethe signol generotorby ot leost l0 kHz ond ensurethot the signol
plus noiseto noise rotio exceedsl5 dB,
{
23-65
RA.l77BMointenonce
AP ll6E-0754-68
Jon.B2(Amdt3)
>
(13)
Retunethe signolgenemtorto the receiver.
(14)
Tronsferthe outputpowermeter, sei to the 600Qmnge, to the l5B LINE
of TSI.
OUTPUIterminols
(15)
switchio LSB'
Setthe frontponelMETER
(16)
Adiusr the LSBLINE LEVELcontrol for on outputof lmW on the front
ponel meter. Ensureihot the ouipul powermeter indicoiion is lmW + ldB.
(17\
Set rhe AGC switch to SHORT.
(lB)
Increoseihe output level of the signol generqtorin I dB stepsuntil the
AGC knee is reochedi.e. whereo furtherincreosein the signolgenerotor
outpui level doesnot result in on increosein oudio poweroutpul. Ensure
thot the signolgenerotoroulput level is lessthon | .7 pV e.m. f.
(19)
Set the signolgenerotoroutput level to 2 pV e.m.f'
(20)
Adiust the LSBLINE LEVELcontrol for o convenient reference level on
the output power meter,
(21)
lncreosethe output level of the signolgenerotorby 100 dB obove 2 pV.
(22)
Ensurethot the increosein the ouipui power level is not greoter thon 5 dB
relotive to the reference level estoblishedot step (20).
(23)
Set the AGC switch to LONG ond repeot steps(19)to (22) inclusive.
23-66
RA.1778Mointenonce
{
MtcRoswtTcH
sA.
@a
\[
ru
\/
SPACINGBAR
LOWEREOGEOF
K N I F I N GS L O TI N L I N E
WITH TOPEDGEOF
SPACINGBAR
TuningCopocitorSetting:
18DegreePoint
Fig.23.1
q!AP=T=ts==L4
o s c I L Lo c RA M s
EA_U_L_T__D_tAgNQ_s_]5-A]{q
CONTENTS
P"g"
INTRODUCTION
24-l
FAULTDIAGNOSISPROCEDURE
fteliminory
PowerSupplies
GenerolFoultLocotion
fteciseFoult Locotion
24-l
24-1
24-l
24-1
OSCILLOGRAMS
24-2
ILLUSTRATIONS
Fig.No.
WoveformDiogroms:LF Loop Boordplv1588
(Sheet l)
WoveformDiogroms:LF Loop Boordplr45g8(Sheef2)
WoveformDiogroms:Upper Loop BoordpM5B9(Sheet I
)
WoveformDiogroms:Upper Loop BoordpM589 (Sheet2i
WoveformDiogroms:TronsferLoop Boord pS33B(Sheet l)
WoveformDiogroms:TronsferLoop Boord pS388(Sheet2)
WoveformDiogroms:HF Loop BoordpS337lSheei t)
WoveformDiogroms:HF Loop BoordpS337(Sheet2)
WoveformDiogroms:34MHz Generotor BoordpM339 (Sheet 1)
WoveformDiogroms:34MHz Generotor BoordpM$g aSheet2)
WoveformDiogroms: 34MHz Generotor BoordpM339 (Sheer3j
WoveformDiogroms:AFC Boord pM664 (AFC OFF) (Sheer l)
WoveformDiogroms:AFC Boord pM664 (AFC OFF) (Sheet2)
WoveformDiogroms:FSK DemodulotorBoordpM35g (Sheet I )
WoveformDiogroms:FSK DemodulotorBoordptvtg68iSheet 2i
PM5B8I
PM588-2
PM589-l
PM589-2
PS38BI
PS3B8-2
PS337-I
-2
P5337
PM339-t
PM339-2
PM339-3
PM664-l
PM664-2
PM368-I
PM368-2
RA,l77BMointenonce
Chop.24
ts (i)
Conten
WARNING BEFORE
WORKINGON THEDECODER
BOARD
PNA694
OR THEMEMORYBOARDPM693THEBATTERY
MUSTBEDISCONNECTED
BYREMOVING
THEBATTERY
LINK ON THEDECODER
BOARD
PA/1694.
FAILURE
TO DO SOMAYRESULT
IN DAA^AGE
CAUSED
BYSHORTING
POWERED
CIRCUIIRY
TO GROUND.
DISCONNECTION
OF THEBATTERY
MAYRESULT
IN THELOSS
OF
STORED
FREQUENCY
INFORMATION.
RA. lZ8 Mointenonce
EIAPLE-L-A4
lA=u!L=p=r4g|=sl!=4!!?==o=s=c=r=L=r__qgjAMs_
INTRODLrcTION
l.
This Chopierprovideso guide to the generol procedureto be fol lowed when
diognosingo suspected
foult, A numberof oscillogroms
ore provided ot the end
of the Chopieros on oid to foulf locoiion,
FAULTDIAGNOSIS PROCED
I.RE
fueliminory
2,
lf o foult is suspected,
checkihot the controlsore set correctlyfor the type of
operotionrequired,ihot the correctsupplyvoltogeis selectedond thot the fuses
ore intoct.
3.
lf the disployfoils to illuminoteor the tuning rongeis restrictedthis moy be due
to the tuning/disployoptionselectedinternollyon the memoryboord.
PowerSupply
4.
set the METERswitchto the +20, +12, +5 ond -7 posiiionsin iurn ond check thot
the oppropriotereodingis obtoinedin eoch cose.
Generol Foult Locotion
5.
lf the receiver doesnor operote correctly in the required mode, chonnel, filter ond
other switch settings, check the operoiionfor olternotive swifch settings. lf correct
operotion con be ochieved for someswitch seftingsbuf not for others this informotion, in
coniunction with the receiver block diogromond interconneciiondiogrom, should provide
on indicotionof the oreo in which the foult lies, Similorly, if correctoperotionionnot be
ochieved for ony switch settings, this ioo should indicote the oreoswhere o foult is mosr
likely.
6.
A numberof signolsore ovoilobleot the reor ponel connections;
o check of these
moy ossistin locotingthe oreo of the foult.
hecise Foult Locotion
7.
Once ii is suspectedthot the foult lies within o porticulororeo, o check should
be mode of the voltoge levels ond signolspresentwithin thot oreo. A numberof
typicol voltoge levelsore given on the circuil diogrom of eoch boord ond, where possible
24-l
RA.l77B Mointenonce
Usingihe
ore providedot-ihe.endof ihe Chopter'
of typicol woveforms
oscillogroms
o"
o' o t"on' of following the signol,throunnt:,:|r"''o
circuii diogromsond block i;;il;
moy ihen be
o smollnumberof components'which
possibleio locole the foult ;;;;hi"
t e s i e di n d i v i d u o l l Y .
OSCILLOGRAMS
of octuol
phoiogrophs
oi ihe end of ihis Chopterore drownfrom
The oscillogroms
of componenttoleroncesonq
disployedon on oscilloscope' Becouse
woveforms
identicol' to those
ou'u'u"a woveformsmoy not oppeor
differencesin meosuring"q;;;t;;;
the
shouldbe simiiorond ihe level within
it'"'*outfo't
ii
snopl
the
However,
shown.
limits sioted.
B.
shouldbe set in occordoncewith the
The receiverond oscilloscopecontrols
informotiongiven in the diogrom'
9.
coniunctionwith-the circuit'ond block
Thewoveformdiogromsshouldbe usedin
of the woveformsond give some
diogroms. Th"t" inJi"ot" ihe circuii locoiion
typicol DC voltogelevels'
10,
L+- Z
RA.1778Moinlenonce
HoRIZoNTAL
SCALE50ns PER DIVISION
VERTICA
SL
C A L E1 V P E R 0tvtsroN
L E V E LL I M I T S
TTL
HoRIZoNTAL
SCALE
0.5ms PER olVlSlON
VERTICAL
SCALEJV PER OIVISION
L E V E L I M N ST T L
tE)I
POINTTP6 (FREOUENC"/
1KHz)
HORIZONTAL
SCALE 0 - 5 ! s P E R O I V I S I O N
HORIZONIAL
SCAE 0.5ms PER DIVISION
V E R T I C ASLC A L EI V PER OIVISION
V E R I I C AS
L C A L E' V PER OIVISION
L E V E LL I M I ] S I T L
L E V E LL I M I T S T T L
HORIZONTAL
SCALE 0 sms PER olVlSlON
VERTICA SCALE IV PER OIVISION
IORIZoNTAL
SCALE20!s PER DIVISION
VERIICAT
SCALEIV PER OIVISION
I E V E I L I M I T ST T L
L E V E LL I M I T S T T L
N o T E :sL T T LT E V E LaSn e < o . o v = i i > z ' r v = i
2. MEASUREMENM
T SA O EA T X X O O O ' O O KI D
H IZG I T SX X A S R E O U I R E D )
TO DETECI
NEI E N S I T YM U S TB E I N C R E A S E D
3 , O S C I L L O S C OIP
NARROWPULSES,
Woveforms:PM
588 Low
FrequencyLoopBoord
Fig.FM588J
L E V E L I M I T ST T L
SCALF20!s PER olVlSlON
HORI2oNTAL
SCATEIV PER DIVISION
VERT'CAL
L E V E L I M N S1 V M I N I M U M
TESTPOINTPIN46 (lMHzINPUT)
TESTPOINTTR19EMIITER
scALE50!s PER olvlsloN
HoRIZoNTAL
SCALE
VERTICAL
IV PER OIVISION
I
tl
4
4
4
q
HoRIzoNTAL
SCALE0 sls PER DIVISION
v E R T I C ASLC A L E0 . 2 V q c P E R O I V I S I O N
L E V E LL I M I I SO2 V P - PM I N I M U M
SCALE2ops PER OIVISION
HoRIZ0NIAL
V E R T I CS
AC
L A L EI V P E R O I V I S I O N
L E v E LL l M l l s 0 . 8 Vd . cM I N I M U M
MHz INPUT)
{r.013-1.020
SCALE0.51s PER DIVISION
HoRIZoNTAL
VERTICAscALE o.Svoc. PER OIVISION
L E v E Lt l M l T s ' l V p - pM I N I M U M
IIORIzoNTAL
SCALE 0.2!s OlVlSloN
VERIICALSCALE lVqc. PER olVlSlON
L E V EL L I M I T Sl V p - p M t N V I U M
FREOUENCY I MHz
N O T E S : 1 T T L L E V E L SA R E < O . E V = O > Z . T V = ' I '
H IZG I T SX X A S R E O U I R E O )
A D EA T X X O O O ' O O K{ D
TS
2 M E A S U R E M E NM
TO DETECI
NET E N S I T M
Y U S T8 E I N C R E A S E D
3 , O S C I L L O S C OIP
NARROWPULSES,
588 Low
Woveforms:PM
FrequencyLoopBoord
588-2
Fig.PM
HoRIZONTAL
SCALE0'5ls PER otvtstON
VERTICAL
SCALE 'V PER orvtstoN
L E V € LL I M I I S T T L
HoRIZoNTAL
scALE 50,rJsPER OIVISION
SCALE'V PER DIVISION
VERTICAL
LEVETLIMTTS
TTL
HORIZONTALSCALE 50 ns PER OIVISION
VERTICALSCALE TV PER otvtstoN
HORIZONTAL
SCAE 50p5 PER OIVISION
V E R T I C ASLC A L E I V PER DIVISION
L E V E LL I M I I S l T L
L E V E LL I M I ] S T T L
HmIZoNTALSCALE50,ps PER DIVIS|ON
VERTICASCALEIV PER OIVISION
TEVEL
T I M I T ST T L
|FRIZoNTAL
SCALE0.1,!s PER OtVtStoN
vERIICAL
SCALE0.2Vq.c. PEq OtVtStON
L E V E LL I M I T sO . a v - 0 . 8 v p - p
/
N o T E :s1 . l T L L E v E LAs R E< o . s v . o > 2 . 1 v = ' l '
2, MEASUREMENTS
MAOEAT XXOOO.OOKHl
IDIGITSXX AS REOUIRED}
INTENSITYMUSTBE INCREASEOTO DETECT
3- OSCITLOSCOPE
NARROWPULSES,
Woveforms:PM
589 Upper
Loop Boord
Fig.PM589'1
TEST POINT
TEST POINTPIN
\
\
I
I
I
I
I
I
I
I
l
f
I
I
I
l
\
\
\
L E V E LL I M I T S
HORIZONTAL
SCALE0,5!5 PER OIVISION
VERTIcAL
SCALE0.5Vo"c.PER DIVISION
L E v E LL I M n S l V D - D M I N I M U M
TEST POINT
TESTPOINT
}IORIZONTALSCALE
HORIZONTAL
SCAE
VERIICALSCALE
VERTICAL
SCALE
L E V E LL I M I T S
L E V E LL I M I T S
TESTPOINT
TESTPOINT
HORIZONIATSCALE
VERTICASCALE
LEVET
LIMITS
IORIZONTAL
SCALE
VERIICALSCALE
SCAE
HORIZONTAL
SCALE
VERTICAL
LEVEL LIMITS
N o T E s : 1 T T L L E v E L s A R E < o . B v= t j
>z.lv - t
H IzG I T S
XX AS REOUIRED)
T SA D EA T X X O O O ' O O K( D
2. MEASUREMENM
DO O E T E C T
NEI E N S I T YM U S I B E I N C R E A S E T
3 , O S C I L L O S C OIP
NARROWPULSES,
Woveforms:PM
589 Upper
Loop Boord
Fig.PM589-2
HoRIZoNTAL
SCALE0.lts PER OIVISION
V€RIICAL
SCALEIV PER orvtstoN
rEvEt ltMlrs tTL
HoRIZONTAL
scALE 5,!s PER O|V|SION
VERIICAL
SCALEIV PER OIVTSION
L E V E LL I M N ST I L
HfilzoNTALscALE s.ps PER 0tVtStON
VERTICAL
SCALE IV PER OIVISION
L E V E LL I M I T SI I L
HORIZONTAL
SCAE s,,rs PER OIVIStON
VERTICAL
SCALE IV PER OrVtStoN
LEVET
L I M I T ST T L
Lr2lC39
HORIZONTAL
SCALE5,!s PER OIVISION
VERTICA5CALE IV PER UVISION
L E V E TI I M I T SI T L
r{RIzoNTAL
SCALE5/s pER 0tVtStON
VERIICAL
scALE 0'SVq.c. pER DtVtSION
LEVL
E L I M I T St 0 0 m V D _ D
NOTES : l _ T T LL E V E L S
A R E < 0 . 8 v= O
>2'rv = 1
(OIGIISXX As REoUIRED}
MEASUREMENTS
MADEAI XXOOO.OOIHZ
OSCILLOSCOPE
INTEN5ITY
MUSI8E INCREASEO
TO OETECI
NARROW
PULSES,
338 Tronsfer
Woveforms:PM
Loop Boord
FigPS 338J
SCALE0.srJs PER OIVISION
HORIZoNTAT
SCAIE 0.2Vq-c.PER OIVISION
vERIICAL
L E V E LL I M I T SO . 5 V P . PM I N I M U M
SCALE0.5.1s PER DIVISION
HoRIZoNTAL
scALE
0'2Vq.c. PER DIVISION
VERIICAL
L E v E LL I M T T3S0 0 mV p - p M I N I M U M
c30
l{trlzoNTALSCALE0.5,!s PER DIVISION
v E R T I C ASLC A L E0 . 5 V q . c .P E R O I V I S I O N
L E V E LL l M l I s 0 8 V e - o M l N l M u M
SCALE0 5!s PER DIVISION
HoRIZoNTAL
ScALE 0'2Vq.c. PER DIVISION
VERTICAL
L Ev E LL I M I T S4 0 0 m Vp - p M I N I M U M
HoRIZotlTAl
SCALE0 l,rJs PER DIVISION
vERTlcA SCALE 0.2 Vq.c.PER DIVISION
L E v E LL lM I T S 3 0 0 mV p - p M I N I M U M
I-IORIZoNTAL
SCAL
E 5,!s PER olvlS|ON
VERTICAT
SCALEIV PER DIVISION
L E V E LL I M I T<S0 . 8 V >I . 6 V R E L A T E OT O
OV
>21v = 1
X
X
O
O O . O O K( D
HI,G I T SX X A S R E O U I R E D }
M
A
O
E
A
T
2 MEASUREMENTS
TO DETECT
M
U
S
T
I
N
C
R
EASED
8E
3 , O S C I L L O S C OIPI IET E N S I ' Y
N A R R O WP U L S E S .
N O T E SI 1 T T L L E V E L SA R E < O ' S V= O
338 Tronsfer
Woveforms:PM
LoopBoord
Fig.PS338-2
HoRIZONTAL
SCALE0.515 PER OIVISION
VERIICAL
SCATE1V PER otvlstoN
L E V E LL I M I T ST T L
HoRIzoNTAL
SCALE'lon! PER OtVtStON
VERTICAL
scALE 'l00mVo.c. PER OtVtStON
LEV€LLlMns 200mV lO lV p-p
T E S TP O I N TI P 5
I
\
I
I
\
\
I
HORIZONTAL
SCALE l0ns
VER]ICALSCALE IV PER
PER DIVISION
DtvtstoN
L E V E ! L I M I T SI T L
HoRIZoNTAL
scAtE 7s
VERTICA
S C A T EI V
L E V E LT I M I I S T T L
PER DIVISION
HoRIzoNIAL
scAE lo,ps PER OtVtStON
VERTICAL
scALE lVo.c. PER uVtSlON
T E V E L T M I T Sl . 8 V f O 8 . S V p - p
tllRIzoNTALSCALE 0,5/s PER OIVISION
VERIICAL
SCAL€ IV PER OIVISION
L E V E TL I M I T ST T L
N O T E S : LT T LL E V E L S
A R E< O . 8 V = O > 2 . 1 V = ' i
MAOFAT XXOOO.OOKHz
{DIGITS
2. MEASUREMENTS
XX AS REQUIREo)
INTENSITY
MUSTBE INCREASEO
IO DETECI
3, OSCITLOSCOPE
NARROW
PULSES,
337 HF
Woveforms:PS
Loop Boord
Fig.PS337-1
l E5l
POINT
scAE lrs PER OIVISION
HoRIZoNTAL
VERTTCAL
SCALEIV PER OIVISION
SCALE
HORIZONTAL
L E V E LL I M I T SI T L
LEVEL IIMNS
VERTICALSCALE
TESTPOINT
|'IoRI
ZONTALSCALEl00ns PER OTVTSTON
SCALEIV PER otvtspN
VERTICAL
L E V E L I M I T ST T L
SCAE
HORIZONTAL
VERTICAL
SCALE
L E V E LL IM IT S
TESTPOINT
POINT
HoRIZoNTAL
SCALEp 5rs PER DIVISION
vERTlcA scALE 0.5Voc. PER OIVISION
L E v E LL I M I T S0 ' 8 V T 0 3 V p - p
IIORIZONTAL
SCALE
VERIICALSCALE
L E V E LL I M I T S
: L T T LL E V E L SA R E < O ' s v . 0 > 2 ' 1 V= ' l '
NOTES
XX AS REOUIREo)
MADEAT xX000.00kH,IDIGITS
2 MEASUREMENTS
TO OEIECT
MUSTBE INCREASED
INTENSTTY
3- OSCTLLOSCOPE
PULSES.
NARROW
337 HF
Woveforms:Ps
Loop Boord
Fig.PS337-2
TEST POINT
ov
HORIZONTAL
SCALE 5ON5 PER OIVISION
VERIICALSCALE IV PER
otvtstoN
L E V E LL I M I T ST T L
HoRIZoNTAL
scALE 10ns PER OIVISION
VERTICAL
SCALE'V PER OIVISION
LEVELLIMTTS
T E S TP O I N TI P 6
I
I
\
HoRIZONIAL
scALE 0 2rus PER OIVISION
VERTICAL
SCALEIV PER DtvtstoN
L E V E LL I M I T ST T L
HoRlZO|]T,AL
SCALE l0 ns
VERTICA SCALE IV PER
L E V E LT I M I I S T T L
PER otVlSrON
DtvtstoN
I
\
I
I
\
I
HORIZoNTAL
SCAE l0n3 PER DIVISION
VERTICAL
SCALEIV PER OIVISION
L E V E L I M I T S' T L
I'IORIZONTAL
SCALE 2,,!s PER OlvlSlON
VERIICALSCALE IV PER OIVISION
L E V E TT I M I I S T T L
N O T F S t T T L L E V F L SA R E < O . S V = O > ? ' 1 V = i .
(OIGITSXX AS REOUIRED}
MADEAT XXOOO,OOKHz
2 MEASUREMENTS
INTENSITYMUST8E INCREASEDTO DETECT
3, OSCILLOSCOPE
NARROWPULSES.
Woveforms,
PM3 39 34MHz
GenerotorBoord
Fig.PM
3 39-1
TESTPOINT
-l
-'l
--1
-'1
I
t
SCALE0.tis
HoRIzoNIAL
HORIZoMAL
SCAE 0'5!s PER OIVISION
VERTICAL
SCALE'IV PER otvtstoN
PER olVlSlON
L E V E LL I M I T 5T T L
VERTICAL
SCALEO.5Vqc.PER OIVISION
L E V E LL l M n s 3 0 0 m Vp - p M I N I M U M
HcRIZONTAL
SCALE0.s,rJs PER O|V|STON
VERTICAL
SCALEIV PER DrvtsroN
L E V E L I M I T ST T L
HORIZONTAL
SCAE O'5J,5 PER OIVISION
V E R T I CS
A cLA L E 0 ' 5 V o . c .P E RO I V I S I O N
! E V E LL I M I T S1 Vp - p M I N I M U M
HqIZoNTALSCALE0.5rrs PER OIVISION
VERIICA SCALE0.1Vq.c. PER OtVtSION
L E V E LL I M I I ST T L
I-IORIZONTAL
SCALE
NOTES: 1. TTL LEVELS ARE (0'8V = 0
VERTICAL
SCALE IV
0's,Is PEROIUSION
PER OIVISION
L E V E TT I M I T S] T L
>- 2'1Y= 1
IGITS
A O EA T X X O O O ' O O K( O
H2
XX AS REOUIREDI
TS
2 M E A S U R E M E NM
INIENSITY MUST8E INCREASEOTO DEIECT
3, OSCILLOSCOPE
NARROWPULSES'
Woveforms:
PM339 3l.MHz
GenerotorBoord
Fig.PM
339-2
scALE 0.5,!s PER OIVISION
HORIZoNIAL
VERTICAL
SCALE0.2 Voc. PER OIVTSTON
L E V E LL I M I T ST T L
SCALElo.us PER olVlSlON
HORIzoNTAt
SCA].Elvo.c PEROvlsloll
VERIICAL
LlMtTs2'8Vp-p MINIMUM
LEVEL
TEST POINT
SCALE0.51s PER
HoRIZoNTAL
vERIICALSCALE0.2 Vo-c.PER
L E V E LL I M I I ST T L
otvtsroN
otvtstoN
SCALE
HORIZONTAL
VERIICALSCALE
L E V E LT I M I T S
TEST POINT
scALE 0.5/s PER OIVISION
HoRIZONTAL
v€RTlcA scALE 0.2Vqq PER OIVISION
L E V E IL l M l I s 5 5 0 m V p - p M I N I M U M
TIORIZONTAL
SCALE
VERIICAI.SCALE
L E V E LL I M I T S
NOTES: L TTLLEVELSARE <O'8V. O > 2'(V='l'
IOIGITS
XX AS REOUIREOI
2 MEASUREMEN1S
MADEAI XXMO'OOKH'
TO OEIECT
INIENSIIYMUSIBE INCREASED
3, OSCILLOSCOPE
NARROW
PULSES'
woveforms,
PM339 3/,MHz
Generotor
Boord
Fig.PM
339-3
PER DIVISION
scAl,El!s PER DIVISION
HoRIzoNTAL
VERI'CAL
SCALE2V PER OIVISION
HORIZONTAT
SCALE0.sis
HORIZONIALSCALE l.ps PER OIVISION
HoRIZoNTAL
scALE 2/s PER DIVISION
SCALE 2V PER OIVISION
VERTICAL
VERTICALSCALE IVcc. PER OtVtStON
VERTICALSCALE 2V PER DIVISION
L E V E ILI M I T ST T L
MLI2 PINS
TESTPOINT
HORIZONTAL
SCALEO.s,ps PER OIVISION
vERTICASCALE0.5 Vq.c.PER OIVISION
HoRIzoNTAL
SCATE2fs PER OIVISION
SCALE2V PER DIVISION
VERTICAL
L E V IE t I M I T sT T L
N O T E S: 1 T T L L E V E L SA R E < o ' s v . O > 2 ' 1 V = ' 1 '
IO'GITSXX AS REOUIRED}
MAOEAT XXOOO'OOKH2
2. MEASUREMENTS
MUSI BE INCREASEDTO DETECI
TNTENSITY
3, OSCTLLOSCOPE
NARROWPULSES.
AFC Boord
Woveforms'PM664
Fig.PM664-1
HORIZOMALSCAE 50ns
PER OIVISION
VERTICAL
SCALE 2V PER
otvtstoN
HoRIZoNTAL
scALEzts PERotvtstoN
VERTICAL
SCALE2V PER OIVISION
L E V E L! I M N S T T L
POINT
l.tGlZONTAISCALE 50ns PER OtVtStoN
VERIICALSCAI.E2V PER orvrsr0N
HoRIZoNTAL
SCAE 2ls pER OtVtStOtl
VERTICAL
SCALE2V PER DIVISION
L E V E LL I M I T ST T L
TESTPOINT
HffilzoNrALscAtE 0.sJrspER OtVtStON
VERTICA
SCALE2V PER DIVISION
I{RIZONIALSCALE
VERTICAT
SCATE
L E V E LL I M I I S
N o T E S: r . T T LL E V E L A
S R E< 0 . 8 V = i i > ? . 1 v = i '
2. MEASUREMENTS
MADEAT XXOoO.OOkHT
tOtGtTS
XX AS REOU|REOI
3, OSCILLOSCOPE
INTENSIIY
MUSTBE INCREASED
,O DETECT
NARROW
PULSES,
Woveforms,
PM664 AFC Boqrd
Fig.PM66t-z
F I L IE R R 1 4C
, l2
HORIZONTAL
SCAE 0 2.rrs PER OIVISION
VERTICAL
SCALE1V P E R O I V I S I O N
0.5ms PER DIVISION
H o R I Z o N TSACLA L E
I E V E LL I M I T S
L E V E LL I M N S
TESTPOINT UNCTIONR2I, R2O
TESTPOINT
HORI
zoNTALSCALE0.irus P E R D I V I S I O N
VERTICAL
SCALEIV PER 0tvlsroN
L
I
M
ITS
LEVE
HORIZONTAL
SCAE 0 . 1 t s P E R O I V I S I O N
VERTICAL
SCALE lV PER DIVISION
VERTICA
SL
C A L E0 . 5 V o c P E R D I V I S I O N
OV
L E V E LL I M I T S
TESTPOINT
HoRIZONTAL
SCALE0'l/s P E R D I V I S I O N
VERTICASCALEIV PER orvrstoN
LE V E LL I M I T S
N O T E S: 1 , T T L L E V E L SA R E < 0 . 8 V = r i
TIORIZONTAL
SCALE
VERTICAL
SCALE
LEVEL LIMIIS
> z , w= ' t
MADEAI X X 0 0 0 . 0 0 k H(zD l G l T SX X A S R E O U I R E D I
2. MEASUREMENTS
DO O E T E C T
NET F N S IY] M U S T8 E I N C R E A S E T
3 . O S C I L L O S C OIP
NARROWPULSES,
PM368 FSK
Woveforms,
Demodutotor
Boord
Fig.PM368-1
SCAE 20M5 PER OIVISION
HORIZONTAL
SCALE 5V PER OIVISION
VERTICAL
L E V E IL- I M I T Sl 2 V - 1 9 V p - p
SCALE0 2ms PER olVlSlON
HoRIZONTAL
vERrtcALscALE 1V dc. PER OIVISION
L E V E LL I M N S I 5 V - 3 V D - o
TESTPOINT
HORI
ZONTALSCALE 20 m5 PER DIVISION
SCALE lV PER
VER'TICAL
DtvtstoN
SCAE
HORIZONTAL
SCALE
VERTICAL
LEVEL LIMITS OEPENOENTUPON FREAUENCY
L E V E LL I M IT S
SHIFT
TESTPOINT
HORIZONTAL
SCALE20MS PER OIVISION
VERTICASCALE'V PER orvtsroN
L E v E IL I M I I S 9 V - l 2 V p - p
I]ORIZONTAL
SCALE
VERTICALSCALE
LEVEL LIMITS
= O > Z ' r V =j '
N O T E :S1 . I T L L E V E L A
S R E< O ' 8 V
(DI6lrSXX As REoUIREo)
MAoEAT xx000'00kH'z
2 MEASUREMENTS
I
N
C
R E A S E] O
D DETECI
MYU S T
BE
3 , O S C I L L O S C IONPTEE N S T T
PULSES'
NARROW
TUNE RECEIVERIN'FSK TUNE'MOOEFOR ZEROBEATWITH CW INPUTFROM
SETTING8Y IOOHZ
RECEIVER
FREOUENCY
THEN INCREASE
SIGNALGENEMTOR,
368 FSK
Woveforms,PM
Demodulotor
Fig.PM
368-2
A$J]ED=IT=g
'=4Y
j I EBy=44egJ=L=
E=
=B=4
=UJj=49
CONTENTS
-P{a.
INTRODUCTION
I
MECHANICAL DE5CR
IPTION
C I R C U I TD E S C R I P T I O N
5kHz Squore-WoveOscil lotor
A
Currenl Pump
SupplyDetector
o
ElectronicSwitch
'7
RECEIVER
SWITCHING-OFFPROCEDURE
12
L I S TO F I L L U S T M T I O N S
Fig.No.
Loyout:l2V BotteryModuleMS540
App.3-l
Circuit: l2V BotteryModuleM5540
App. 3-2
Loyout: BotteryModule rcB PS546
App. 3-3
Appendix3
RA. IZB Moinienonce
Contents(i)
4JJ=E|!q!X=q
LaY=I AJJ=E!!l_499 g! ! =s_s=5_4_0
INTRODTJCTION
When the POWERswitch on the RA. l77B is set from OFF ro ON, the kHz porrion
of the digitol frequencydisploy is outomoticollyresetto 00.000. lt followsthis
ihot should o brief interruption of ihe power supply input occur, the kHz portion of the
receiver frequencywill ogoin be reset to zero. In order fo retoin the frequency setiing
informoiion of the receiver during o brief interruption of the supply inpuf, ond so ovoid o
possiblelossof receivedinformotion,the l2V botterymoduleis ovoiloble os on optionol
extro.
L
N O T E : The moduleis copobleof operotionfrom q nominol I l0V or 240V supplyinput
without need of odiusiment,
MECHANICALDESCRI
PTION
2.
Thebotterymoduleconsisfs
of o smollmetolbox housing
o re-chorgeoble
nickelcodmiumbotteryond o printedcircuit boord. Themoduleis mountedon the reor
ponelof the receiverond is held in plocewifh two screws.Themoinpowersupplyinputis
connectedio the modulePowER/P plug ond the powERo/p socket,on o flying leod, is
connectedto the receiverPOWER
plug. Twofurtherflying leodsprovidefor the connecf'ron
(ot TS2on the receiverreor ponel)of the l2V outputto the receiver+lzv/srD terminol
(red)cnd the +l2V input fromthe receiver+r2v rerminol(oronge), A boiteryoN/oFF
swirchondo DATE oF tAsT CHARGElobelore included. Theloyoutof the moduleis
g i v e ni n F i g . A p p . 3 - 1 .
C I R C U ID
TESCRIPTION
3.
F i g .A p p .3 - 2
The +l2V supply from the receiver is usedio power ihe SkHz squore-wove
oscillotor, the currentpumpond the electronicswitch.
4.
The 5kHz squore-woveoscillotor MLI is o free running ostoble multivibrotor
with copocitor c2 ond resistorR2 os the timing components. The output ot pin
l0 on ML I is o l2v peok-io-peok I : I rotio ,q*r.-*Juu which is fed to the
pr.p
"u,,"n,
tronsistorslRl ond TR2.
RA.1778Mointenonce
Appendix3
PogeI
Curreni Pump
When the output fromMLI cousesTR2to conduct, it chorgescopocitorC3 vio
diode D2 ond the currentlimiting resistorRl. When the outpuf from MLI couses
TRI to conduci, it tronsfersthe chorgeon copocitorC3 ro the botiery vio resistorR6,
diode D4 ond switch SWI .
5.
SupplyDetector
Themoin supplyinput oi boordpins B ond 6 is full-wove rectified by Dl ond is
of o light-emitting
then opplied vio R5 io on opticol coupler, ML2. Thisconsists
diode (LED)ond o phoio-tronsistor,When the supplyis presentthe light-emittingdiode
to conductond effectively connectML2 pin 5 to 0V
illuminotesfor the photo-tronsisior
to ensurethot TR5will be cut off.
6.
ElecironicSwitch
7,
of ihe electronicswilch ore os follows:The reouirements
(l)
To ollow ihe boitery to chorgewhen the receiveris workingnormolly.
(2)
To qllow the bottery lo provide o +l2V supply ot boord pin 4 should o
moin supplyfoilure occur whilst the receiveris in use(i,e. receiver
POWERswitch set to ON).
(3)
To prevent dischorgeof the bcttery when the receiver POWERswiich is
sef fo OFF.
(4)
To prevent further botfery dischorgeshould the bottery voltoge foll below
opproximotelyl0V.
is given
Theoction of the electronicswitch for eoch of the oboverequirements
below.
When the receiver is working normolly, ihe presenceof the +l2V supply ot boord
pin 3 cousesTR6to conduct(vio Rl l) which in turn switcheson TR3ond TR4.
The +t5V (opproximotely)ouiput from the current pumpchorgesihe bottery vio the bottery
ON/OFF switch ond is olso opplied to the receiver +\TV/STD terminol vio TR4, D6ond
boord pin 4.
8.
9.1
Shouldthe moinsupplysubsequently
foil whilstthe receiveris in use, the lightin ML2of the supplydetector
emiitingdiodeextinguishes
ondfhe photo-tronsistoi
ceosesto conduct, ond, provided the boftery voltoge is greoter thon l0V, the resultont
current flow through R9 producesopproximofely0.7V ot the boseof TR5cousingthis
ironsistorto conduct. TR6ceosesto conducf (since the +l2V supply from the receiver is no
longer ovoiloble) but the conduction of TR3ond TR4is mointoined vio TR5ond the bottery
is ollowed fo dischorgevio TR4, D6 ond boordpin 4.
RA.l77B Mointenonce
Appendix3
Poge2
10.
when, whilst the moin supplyis ovoiloble ond connected,the receiver powER
switch is set to oFF, boih TR5ond TR6ore held off to prevent conduciion of TR3
ond TR4,ond so isoloie the bottery. lf, however, the moin supplyis disconnectedwhilst
ihe receiver PowER switch is set to oN, then the botterywill becomefully dischorgedin
oppoximotely30 minutes,it is imporionfto ensurethot doesnot occur (e.g. during
ironsportoiion
etc).
I l.
lf the on-lood botferyvoltogefolls below l0V, D5 ceosesto conduct, TR5
switchesoff ond lhis in iurn switchesoff lR3 ond TR4to isolote the bottery. The
electronicswilch moy be resetonly by restoringfhe moinssupplyond swifchingon the
receiver.
RECEIVER
SWITCHING-OFFPROCEDURE
12.
To prevenf dischorgeof the boitery during periodsof inoctivity or tronsportotion
the following swiiching-offprocedureshouldbe odopted:-
13.
(l)
Set the receiverSUPPLYswitch to OFF.
(2)
Disconnectfhe receiver from the moin sourceof power or trip the cxtrrnrl
circuif breoker,os required.
(3)
The bottery ON/OFF switch is provided os o sofeguordfor usc when the
botterymoduleis not fitied lo fhe receiver,
Appendix
RA.1778Mointenonce
Poge3
BAITERY
ON
\e/
//A\
I
A
I
I
PRII{TEDCIRCUIT
BOARDPS516
Loyout
lzv BatteryModuleMS540
FieApp.3.l
t12V INPUI
FROM+IzV TERMINAI
(FLYINGLEAD)
{ 1+t2vouTPuI
-WAVE
sKHz SOU,ARE
OSCILLATOR
WARNING: LETHAL VOTTAGES
ARE PRESENT
ON
IHIS BOARD,
ELECTRONIC
SWITCH
SUPPLYDETECTOh
-t--Tr
I
SUPPLY
rOUTPUT
={l
SKI
FlYINGLEAO)
I
I
ii
I
I
PS546
TRANS|STORS
BFX18
TRI,]R3
2N2369
TRi rRA
rR5,TR6
BFYsI
lR,i
Bcr0s
TR2
I
I
I
I
I st-spEs
I
Bs6
01
BZY88C6V2 D5
I
I0Dl
D2,D3,D{,D6
I
I N T E G R A I ECDT R C U I I S
10t1a\
FC0820
MLI
ML2
I
I
I
EEME
twoH7049
|
Circuit
:12VBotteryModute
MS540
Fig.App.3.2
W{
#
R.ryl
Ug
s
3
@ffi@
&6
En
e
n
rJ
o
l-
1
R7
D4
R1
e
o
S
c
46s
Loyout
BotteryModulcPCB PS546
Fig.App.3.3
A P P E NIDX 4
I FC O N V E R T E
MRO D U L EM S . 5 6 I
CONTENTS
P"I1.
INTRODUCTION
I
CONSTRLJCTION
5
C I R C U ID
T ESCRIPTION
1. 5MHz Generotor
7
o
Mixer Stoge
ll
I00kHzStoges
12
Sidebond
lnversion
TUNED C IRCUIT ALIGNMENT
14
I e s r E qu r p m e nr
t4
heliminory
l5
I .5MHz TunedCircuit
l6
l00kHz Filter Checks
17
l00kHzFi lier Alignment
l8
ILLUSTRATIONS
irs.
Circuit: lF ConverferModuleMS.56l
App.4-l
Generol View: lF ConverterModule MS.56l
App.4-2
Circuit: lF Converier BoordPS604
App. 4-3
Loyout: lF Converter BoordPS.604
App.4-4
Appendix4
RA.l77B Mointenonce
Contents
AP Il6E-0754-68
Dec. 79 (Amdt.I )
APPENDIX
4
IF CONVERTER
MODULE
MS.55I
INTRODI.JCTION
l.
The lF Converter Module occepts the l.4MHz IF oufpufs from the receiver ond
converts them to l00kHz lF oufputs for externol use.
2.
Two versionsof the Module ore ovoiloble, The MS.56l/B provides for ISB
operotion ond contoinstwo identicol signol poths, one eoch for the Moin
ond lsB receivor lF outputs. The M5.561/A, usedwith receivers equippedfor ssB operoiion,
contoins circuitry for lhe Moin lF poth only,
The l.4MHz lF inputsto the Module ore seporotelymixed with o l.SMHz
corrier signol . The resultoni l00Hz signolsore filtered ond omplified to provide
the desiredoutputs. The l.5MHz corier is derived intemolly from the lMHz reference
frequencysource (ovoiloble ot the reor ponel of the receiver).
3.
4.
The module is poweredfrom the receiver's l2V d.c. supply.
CONSTRIJCTION
5.
The rmit consistsof o flonged bcse plote with brocketsfor mounting two prinied
circuit boords. The bose plote is ottoched to the receiver reor ponel with four
screwsond o cover is held in ploce with two Dzus fosteners.
6.
The extemol signol connectionsore mode vio five cooxiol connectors(three for
the MS.56l/A).
The d,c. supply is fed vio o poir of flying leods which connect
+l2V
to the
ond E terminols of the receiver. The loyout of the unit is given in Fig. App.5-2.
CIRCUIT
DESCRIPTION
No. 2, PL2ond 5K2 ore omittedfor the 5SBversion.
8.
Sincethe Moin ond ISBsignolpothsore identicol, only the A4oinpoth will be
described.
The lMHz referencefrequencyinput is fed vio PL3(pin 3 of the boord)to omplifiey'
shoperstogeIRI. Ihe resultontsquorewove
signolis oppliedto MLlo which
functionsos o divide-by-two-stoge. MLlb is not us6d.
9.
TheQ ond Q outputsfromMLlo, o 500kHz squorevrove
signol, ore opplied in
push-pullto tunodcircuit Tl, C5. Tl is tunedto I.5MHz ond selectsthe third
hormonicof the 500kHzsqurrewoveto drive mixer ML2.
10.
RA.\Z8 Mointenonce
Appendix 4
FogeI
Mixer Stoge
The receiver MAIN lF output is opplied vio PLI (pin I of the boord) to ML2 pin I
ML2 functions os o double-boloncedmixer stoge ond hence reducesony corrier
(l.5MHz) ond tF (l.4MHz) signolswhich oppeorot the mixer output. ML2 operoting
potentiols ore determined by potentiol divider choin R14 io R16. The stoge goin is set
by Rl0.
I l.
l00kHz lF Stoges
The lOOkHz lF output developed ocrossR9 is possedto o bond-possfilter consisting
of Ll, C6, A, Q, L3 ond Cl0. The filter possbondis from 92kHz to lO8kHz
ot the 3dB points. After filtering, the signolsore opplied to outPul omplifier stoge IR2
ond then vio T2 to lhe oulput socket SKl. The overoll goin of the Module is obout 6dB.
12.
Sidebond Inversion
Sincethe 'locol oscillotor'frequencyis obovefhe l.4MHz lF input, sidebond
'erect' with
inversionoccurs. Thefinol (l00kHz)outputsfrom the MS.56l ore
respectto thoseot the ontennoinput, i.e. on USBreceivedsignolresultsin on USB
output.
13.
ALIGNMENT
TUNEDCIRCUIT
Test Equiprnent
The itemsof test equiprnentlisted belowore requiredfor the following
list given in Chopter5 of the
tests. Theseitemsform port of the consolidoted
MointenonceMonr.nl.
14.
(I )
(2)
SignolGenerotor(2 off)
FrequencyRonge:
lMHz to 2MHz
Output Level:
5OnVto 500mVr.m.s.
Output lmpedonce:
50 ohms
Multimeter
(Exomple:AvornelerModel 8)
(3)
HF ElectronicVoltmeter
Ronge:
50 Millivolts fo I volt r.m.s.
FrequencyRonge:
Up io 2MHz
RA. 1778Mqintenonce
Appendix4
Foge2
Input lmpedonces:
50 ohms,ond high impedonce
(Exomple:Airmec 30lA or Fomell Type TM6 with probe_to_Ntype
odoptor, 50 ohm rerminoied , Type IM6/4).
(4)
Digitol Frequency
Meter
Frequencyronge:
Up to 2MHz
Accurocy:
lnternolstondord:
I port in 106+ I count.
(Exomple:RocolInsfruments
Type 9822 or Type?021).
(5)
+l2V d.c. supply,roiing l00mA.
(l)
Removethe cover from fhe module (two Dzusfosteners).
(2)
Connectthe Module to rhe +l2V supply(orongeflying leod to +12y,
block leqd ro 0V. Swiich the supplyON.
(3)
Meosureihe current drown by the Modure. This shouldnot exceed
l00mA d.c. for rhe MS.56l/B versionof 50mAfor ihe MS.56l/A
version.
fteliminory
15
I .5MHz TunedCircuit
16
(l)
Connecfthe SignolGenerotorA to the lMHz input (pL3).
(2)
Sef the sisnol.input frequency to lMHz + l00Hz ond the signol inpur
level io 400mVe.m.f ,
(3)
Connecf the high impedonceinput of the ElectronicVoltmeter ro
test-poinrTpl on pCBl (Moin lF porh).
(4)
Check rhqt the level ot Tpl is of leost l5OnV r.m.s. lf nor, odiust
the core of TI for o moximun output reoding.
l00kHz Filter Checks
17
(l)
ConnectSignolGenerororB to the Moin lF inpui (pLl).
(2)
Set the sig,nolinput frequencyto l.4MHz + I00Hz ond the signol input
level to l00mV e.m. f .
RA.l77B Mo intenonce
Appendix4
Poge3
(3)ConnectiheE|ectronicVoltmeterocrosstheMoinl00kHzlFoutput(SKl)'
TerminoteSKI into 5Oohms'
(4)
(5)
between70mV ond
Meosurethe 100kHzoutput level which should be
l 4 0 m Vr . m ' s ' N o t e t h e o c t u o lv o l u e '
ond
Tune Signol Generotor B through the ronge 139fuH2jo l408kHz
-3dB of the volue noted
check t-hotfhe output is mointoinedwithin
obove.
(6)
the reolignment
lf the desiredresultsore not obtoined' corry out
(5) '
proceouresof poro' 18 o-ndthen rePeotsiePs(2)' (4) ond
(7)
TrqnsferSignol Generotor B to PL2'
(B)
qnd the 50ohmterminotion to
Tronsferthe ElectronicVoltmeier
(9)
Repeotsteps(2), (4\, (5) ond (6) for ihe ISB lF poth'
NOTE:
Sieps(7) to (9) ore omitted for the MS'561/A version'
SK2'
l00kHz Fi lter Alignment
18.
relevont test equiprnentconnections
This procedureopplies
'Pi2 to eiiher boord-',-The
'
ond output from SKI or SK2)ore ossumed
(input to Pl-t or
(l)
Open-circuit links A-B ond A-C on the boord'
(2)
Voltmeter to testConnect the high impedonceinput of the Electronic
Poini TP2'
(3)
Check thot the signol input frequencyis l '4MHz + l00Hz'
(4)
Voltmeter'
Adiust the core of Ll for o moximumoutPut on the Electronic
(5)
Connectlink A-C'
(6)
Voltmeter'
Adiust the core of L2 for o minimum outPut on the Electronic
(7)
Removelink A-C ond connect link A4 '
(8)
output' Terminote
Tronsferthe ElectronicVoltmeter to the 100kHz lF
ihis Point into 50 ohms'
(9)
ElectronicVoltmeter'
Adiust the core of L3 for o moximumoutPut on the
(10)
of poro' 17'
Hoving oligned Ll, L2 ond L3' repeot ihe procedures
RA.1778Mointenonce
Appendix4
Poge4
P C BI
I S 8 V E RS I O N
SSB VERSION
E]EIEIEII'
Circuit:IF Convertcr
ModuteMS.561
Fig.App.4-1
I O + 1 2V
o@
@
EElENtr
t w o H? 0 4 9|
Gencrql View : IF Converter
ModuteMS.561
Fig.App.4-2
t-i
t-!!!E!-!!4r!EL
at0
.09,
MEEfi'
11
Tl{iD tt Et'roitr 54fcl
lwt
Tt toi
tutf{l}'t
t.Stitz
l.alttz
lt
mut
llll
It2
CoioBll
t96BC
Iit
lt2
!q09
tt!!66
t2
LI
at5!a
cla6'35
cta6t5a
Tt clatS!!
TZ Cla703a
IOIIL
(ll[l urt (ul TUt€u FoAtallraul rooftrz^T tr?.
Lrn l T0c t|,|t u ol irutiu|| tofitiz ll t?e.
t€cotii€cTLrn r T0 E.
lultt (! Fot |lll|t'ij 100{tz tl r.f.0tTPUI
lF Conv
Circuit:
BoordPS.60
troffZ ! r[flZ FrrTEr
IOOiHZOUTruT&J'FEi
J!J&
ll?tl utt (Ltl TutE Lt aoi ratflr{u|,troor{z rr t??.
!l|| I T0 C lua€ U Foi lllll{ljl,l l00lllz ll Tt?,
iEcoNttcT L||fi I ro 8_
TUit !! toi |l^I|li,t 100$z rT rf.otTpul
IF Converter
Circuit:
BoordPS.604
Fig.App.4-3
#d.6=l
]E
c6 Bl
;
4-lo
o
i@EL
-IFI@f
=
is"i
E
q;#
tl
!cl
cr)>
s{
tt.l
MKEil'
Loyout:IF Convertcr
BoardPS.601
Fig.App.1-4
SUPPLEMENT
I
IMRODUCTIOT
NO T T LL O G I C
INTRODUCTION
I,
Thisoppendix
provides
o generoloutlineof TTLlogicwith o brief description
of
someof the TTLlogicdevicescommonly
usedin Rocolequipment.
TTLVoltogeLevels
2.
T T Lc i r c u i t so r e o p e r o t e d
b y d . c . l e v e l s ,s o o d , c . c o u p l e do s c i l l o s c o pm
e u s tb e
usedwhen monitoringwoveformsin o TTL circuit.
3.
TTLvoltoge levelsore definedos follows:Logic '0' is definedos lessthon 0.8V,
Logic 'l' is definedos open circuit or greoterthon2.4Y.
Any voltogebetweentheselevelsis o poientiol foult condition, os fhe inpui stote
is then undefined. Theexceptionto this is the SchmiiiTrigger(porogroph
4).
4.
A SchmitiTriggercircuii converson onologueinput, e.g. o sinewove,into o
squorewove
outpui ot TTLlevel. The input signolmustswingbeyondcertoin
prescribedlimits or no outpufwill result. For exomple, the 7413Jschmitt Triggerhos
the fol lowing input requiremenrs:L e s st h o n0 . 8 V i n p u ti o p r o d u c eo l o g i c , 0 ' o u t p u t ,
Greoter thon I ,6V input to produceo logic 'l' ouipui.
5.
At very high frequencies
TTLwoveformsmoy oppeoron on oscilloscopeos sinewoveswith on omplitudelower thon the levelsdefinedin porogroph3,
Inyerton
6.
A O o n o l e o dd e n o t e so n i n v e r s i o n o, s d o e s o - o v e r o s y m b o .l I n t h e c o s eo f o n
input leod, the inversioncouseslhe input to be octivotei by o'0,, otherwisethe
inpui is octivotedby o 'l'. An inversionon on outpui leod negotesthe function of o
device, for exompleon AND gote with o e on its output is o NAND gote.
PogeI
RA. I 778 Mqinienonce
SupplementI
TTL NAND Gotes
7.
The symbolfor o NAND goie ond the relotionshipbetweenthe output ond the
inpuisis os follows:-
INPUTS
OUTPUT
when oll inputsore 'l', output is '0'
i f o n y i n p u t i s ' 0 ' , o u t p u ti s ' l '
NAND Gote
F i s . S u p p .I . l
A NAND gote moy be usedos on ONIOFF gote io inhibii or enobleo digitol
signol. A 'l' opplied to the 'control' input ollows the signol opPliedto the other
'0' is opPliedto the 'control' input the output
input io oppeorinvertedot the output. lf o
'
l
'
.
w i l l r e m o i no t
8.
coNrRoL---f\
l-F__ uLru
) t_Ju L ------./,/
NAND Gote usedos ON,/OFFGote
Fig. Supp. 1.2
g.
The ON/OFF function of the NAND gote moy be extendedto provide chongeov'
switchingbetweentwo digitol signols,employingthe following configurotion. A
'l' on the 'control ' input cousessignol A to oPPeqrot the output; o '0' on ihe control input
couseso signol B to oPpeorot the ouiput. In this coseno overoll invenion tokesploce.
Poge2
RA. l77BMointenonce
Supplemet
!
NAND Gotes usedos Chongeover
Switch
F i g . S u p p .t . J
T T LF l i p - F l o p s
10.
D typeFlip-flop
(l)
Thelogic symbolfor o D rypeflip-flop is os follows:-
.O,
INPUT
C L O C KI N P U T
D typeFlip-flop
(2)
OUTPUTS
F i s . S u p p 1. . 4
The relotionshipbetweenthe vorious inputs ond outputs, os shownon the
obovediogrom, is given in the following truth toble:-
RA, I77BMointenonce
I
Supplement
TRUTH
TABLE- D TYPEFLIP-FLOP
OUTPUTS
IN PUTS
ck
D
PR
CL
a
X
X
0
I
'lo
X
X
I
X
X
0
0
I
I
I
'lo
0
I
1
0
rJ
0lr
lndeterminote
ll
'0' or '1')
X - indicotesthot the input stoie is not significont(moybe
I l.
(3)
input or the GLEARinput moy be shownnot connectIn somecosesthe PRESET
ed or omittedfrom the logic symbol. This indicotesthot the input is ot logic
'l ', the inociive stoie.
(4)
Only posiiive tronsilionsof the CLOCK input ore significont, negotive
ironsitionshwe no effect.
J-K type Flip-flop
(l)
The logic symbolfor o J-K type flip-flop is os follows:-
INPUT
CLOCK
OUTPUTS
INPUT
J-KFlip-flop
(2)
F i s . S u P P .1 . 5
The outputsof the flip-flop chonge, occordingto the inputs, ot negotive.
tronsitionsof the CLOCK input. The relotionshipbetweenthe inputsond
outputsis given in the following truth toble:-
Poge4
RA. 1778 Moinienonce
Supplement
I
- J - K F L I PF L O P
TRUTH
TABLE
B E F O RCEL O C K AFTERCLOCK
J
t<
0
0
I
No chonge
I
0
r lo
0
I
0lrI
I
I
Toggles
TTL Counters
t2.
Divide-by-ten counter,
(l)
The logic symbolfor o iypicol divide-by-ten counteris os follows:OUTPUTS
Divide-by-ten Counter
F i g . S u p p .1 . 6
(2)
The output of the counreris in binory-codeddecimol, with D ihe most
s i g n i f i c o n bt i i .
(3)
lf both R0inputsoreot 'l' the outputis resetio zero, lf boih R9 inputs ore
o t ' l ' t h e o u t p u it s r e s etto n i n e( 1 0 0 1 ) .
(4)
WhentheR0 ond R9inputsore '0' the countercountsthe clock pulsesot
CKI ondCK2, Voriousdivisionrotiosmoybe obioinedosfollows:-:2 - inputoi CKl, outputot A
i5 - input oI CK2, outputot C or D
i l 0 - i n p u to r C K l , l i n k A o n dC K 2 , o u r p uor t D
(5)
Whenwiredfor divide-by-ten
operotion,the countercounisto nine ('r00r)
then, on the next clock pulse,resetsto zero (0000).
RA,,l77B Mointenonce
Poge5
Supplemeni
rJ,
divide-by-ten counter
Progrommed
(i)
divide-by-ten counteris os
The logic symbolfor o iypicol progrommed
fol lows:-
Divide-by-tenCounier
Progrommoble
I rg. )upP, | . /
(2)
'l' the counier
When Ao ond CK2 ore linked (osshown)ond STBis ot
operotesos o conventionolBCDdivide-by-ten counter.
(3)
Whenthe STB(strobe)line is '0', both clock inputs(CKI ond CK2) ore
direcily to the
inhibited ond the doto on the Do-Dd inpui lines is tronsferred
'l'
the countercontinuesto
Ao-Do ouiputs. When the STBline returnsio
pulses.
inpuf
count CKI
(4)
The counter moy therefore, be progrommedto divide by ony numberN up to
ten by presettingwith o numberI0-N ot the inputsDo-Dd ond opplyingo
'0' STBpulse. WhenSTBreturnsto 'l' the countercountsnegotive
ironsitionsof CKI unfil nine (1001)is reochedot Ao-Do; ot the Nth clock
fronsition the counter resetsto zero (0000)' Thusif o numberl0-N is preprogrommedinio fhe counter o negotive tronsition is obioined ot Do when
N clock inputshqve been receivedot CKI . The negotivetronsiiionmoy
be usedto clock the next sloge in o counter choin ond moy, therefore, be
regordedos o 'corry' output.
(5)
When the counter reseisto zero it mustbe re-progrommedif o division rotio
other thon ten is required,
TTL Monostobles
14.
(l )
is crsfollows:The logic symbolfor o typicol TTLmonostoble
Poge 6
RA. l77B Mointenonce
Supplement
IN PUTS
OUTPUTS
Monosioble
(2)
F i s . 5 u p p l. . B
The monostobleproduceson outputpulse, of durotion
determinedby the
voluesof R ond C, uponreceipt of the oppropriote
tronsition ot A or B.
lis operotion moy olso be inhib ired by the oppropriote
input ot A or B. The
relotionsh
ip betweentne inputsond outputsis shownin
the following trurh
toble.
TRUTH
TABLE- MONOSTABLE
IN PUTS
OUTPUTS
A
B
o
I
X
0
X
0
t
r
I
I
I
-Lr
JI
n U
JL
X - indicotesthoi the input stote is not significont(moy
be '0' or 'l').
Poge 7
RA. 1778Mointenonce
Supplement
SUPPLEMENT
2
I N T R O D U C T I OTNO C M O SL O G I C
INTRODUCTION
l.
Thisoppendixprovideso generolouiline of cMos logic wiih o brief description
of someCMOS logic devicesusedin Rocolequipment.
CMOS Volioge Levels
2.
cMOS circuits ore operotedby d.c, levels, so o d.c. coupledoscilloscopemusi
be usedwhen monitoringwoveformsin o CMOS circuit,
3.
CMOS voltoge levels ore definedos follows:Logic '0' is definedos lessthon 30/o of ihe supplyvoltoge (VDD).
Logic 'l' is definedos moreihon 70/" of the supplyvoltoge (VDD).
4,
ln generol, ihe ouiput of o CMOS circuit is BDDfor o logic 'l ' ond 0V for o
logic '0'. The input ond ouiput voltogesmusrnot be outsidethe ronge0v to vDD.
5.
Inputsto cMos circuits mustnot be left open circuit os this moy domogethe
device. The output of o cMo5 circuit moy be connectedto o/ or VDD for short
periodswithout domoge.
CMOS Gotes
6.
AND ond NAND gotes.
The logic symbolsond relotionships
beiweeninputsond outputsof AND ond NAND
gotesore os follows:-
I NPUTS
OUTPUT
w h e no l l i n p u t so r e ' l ' , o u t p ui s ' l ' .
if ony inputis '0', outputis '0'.
AND Gote
F i s . S u p p .2 . 1
Poge I
RA. l77B Mointenqnce
2
Supplement
INPUTS
OUTPUT
'0"
w h e n o l I i n p u t so r e ' l ' , o u i p u ii s
'
l
'
.
i f o n y i n p u t i s ' 0 ' , o u t P u ti s
F i s .S u p p . 2 . 2
NAND Goie
7
OR ond NOR goies
The logic symbolsond relotionshipbetweeninputsond outputof OR ond NOR
gqtes ore os follows:-
INPUTS
OUIPUT
' 0 '.
when oll inputsore ' 0 ' , o u t p u its
'l'.
if ony input is 'l ', o u t p u its
Fi9.Supp.2.3
OR Gqte
INPUTS
OUTPUT
when oll inputsore ' 0 ' , o u t p u its ' l '
'0'
i f o n y i n p u ti s ' l ' , outputis
NOR Gote
Fig.Supp.2.4
Page 2
RA, 1778Mointenonce
2
Supplement
A
ExclusiveOR gote
(l)
The.logicsymbolond reloiionshipbeiweenihe inputsond output
of the
exclusiveOR gote ore os follows:-
INPUTS
OUTPUT
if boih inputsore the some(,0' or '1,) output is ,0'
if inputsore different, output is 'l'.
ExclusiveOR Gote
(2)
r t g , ) u P P .2 . 5
The exclusive OR gote moy De useoos o pulse generoior,
by conneciing | l
os follows:-
INPUT
ExclusiveOR PulseGenerotor
OUTPUT
F i s . S u p p .2 . 6
Wheno.oositiveor negotivetronsitionoccursoi ihe input,
the voltogeot
ot eointA for o periodderermined
by'RondC, ..J]luri"g
l:,,:l^1,1^".,nr
rhts period, lfrot
the output is 'l' becouse
A ond B ore difiereni. Whenihe
voltoge oi B opproximotesto thoi ot A, the output
returnsto ,0,. In this
woy o pulseis generofedfor every input tronsition,
so the circuit will oct
os o pulsedoubler, os shownin the following diogiom.
(porNl
rNpuT
^, --J---l-,
INPUT
+ OELAY
(POINT
B)
OUTPUT
PulseDoubling
r t g . > u p p ,Z . /
Theoutputpulselengthis 0.4 RCto r . z K L s e c o n d s .l h e
a n p u tp u l s e
lengihmusiexceedthis,
Poge3
RA. 1778 Mointenonce
Supplement
2
CMOSFlip-floPs
9.
D-typeFlip-flop
(l)
Thelogicsymbolfor o D iype flip-flop is osfollows:-
O INPUT
OUTPUTS
C L O C KI N P U T
Fis. Supp.2,8
D-type Flip flop
(2)
The relotionshipbetweenthe voriousinputsond outputsis givenin the
following iruth ioble.
TABLE- D-TYPEFLIP-FLOP
TRUTH
OUTPUTS
IN PUTS
ck
f)
S
K
X
X
I
0
X
a
r l0
'|
0lr
lndeierminoie
X
0
X
I
I
I
v
0
I
r
J
0
r lo
I
0
ll
'0' or 'l') '
X - indicotesihot the input siote is not significoni(moybe
(3)
Only positivetronsitionsof the CLOCK input ore significont; negotive
tronsitionshove no effect.
(4)
A D-type flip-flop moy be connectedos o monostoble,o in the following
d iogrom.
_f-1OUTPUTS
1_r
D-type Monostdle
F i s . S u p p2. . 9
Poge4
RA. 1778Mointenonce
Supplement
A p o s i t i v et r o n s i t i o no n t h e C K i n p u i c o u s e se i o g o i o ' 1 , . T h i si s o p p l i e d
to the R inpui, vio the timing circuit RC, io resetthe flip-flop ond couse
e
to returnto '0' ofter o perioddeterminedby R ond C. The puiselength
is
0 . 4 R C i o 1 . 2 R Cs e c o n d s .
I0.
J-K Flip-flop
(l)
The logic symbolfor o J-K flip-flop is os follows:-
J, INPUT
)'o
CK
Kd
CLOCX
K,INPUT
OUTPUTS
R
J - K Flip-flop
(2)
Fis. Supp.2.l0
The S ond R inputsoverrideihe J,
_Kond CK inputs, which ore octive only
when S ond R ore both '0'. The relotionship
betweenS qnd R ond the out_
puis is given in the following truth toble.
TRUTH
TABLE(I) - .I-< FLIP-FLoP
CONIROLINPUTS
s
R
0
0
0
I
ruth
Toble (2)
^l
I
rl
I
I
OUTPUTS
I
;l
* - in this cose
Q ond 6 ore ,l,; this condition is involid.
(3)
When both S ond R ore '0' the output ofter o clock pulse is deierminedby
J,. K ond the outpui beforethe clock pulse, os shownin the following truth
toble. Only positiveclock tronsitionsore significont.
Poge5
RA. 1778Moinienonce
2
Supplement
( 2 )- J - K F L I P - F L O P
TABLE
TRUTH
CLOCK
CLOCK A F T E R
BEFORE
N
ol
rl
l0
I
I
0
I
I
I
^l
"l
0l
I
0
I
l0
I
I
0
l0
0
I
0l
I
0
l0
n
I
0l
I
0
0l
0
0
0
I
CMOS Dividen/Counters
ll.
(r)
The logic symbolfor o iypicol progrommobleUP/DOWN CMOS counter
is shownbelow.
D A T A O U TP U T S
CLOCKENABLE
ABC
U/D
cE
INPUI
CLOCK
CK
UP/OOWN
D
co
CARRY OUTPUT
Do 0b 0c Dd Pe *
I . M A YB E R ( R E S E T
I N P U lO
) RB / O
{BINARY/DECIMAL
I NP U T )A C C O R DGI N
ENABLE
PRESET
T OT Y P E .
UP/DOWN Counter
Progrommoble
(2\
(3)
Fig' Supp' 2' l I
input'
The Pe ond R (where provided) inputs ore stotic ond ovenide the CK
'l'
to
the
ABCD
directly
the doto on the D inputsis tronsferred
lf Pe is
'l' the ABCD outPutsore resetto zero'
outputs. lf R is
'0' the CK input is octive
When Pe ond Ce ond R (where provided) ore ol.l
ond the countercounispositivetronsitionsot this input'
Poge6
RA. i77B Mointenonce
2
Supplement
(4)
The directionof couniingis deierminedby the U / D i n p u t . l f U / D i s ' l '
i h e c o u n t e rc o u n t su p w o r d s( 1, 2 , 3 , . , , ) , i f U/D is '0' the countercounts
d o w n w o r d(s. . . 3 , 2 , l ) .
(s)
\{hen o B/D input is provided the counier moy b e u s e d o s o b i n o r y ( - l 0 )
counier (B/D = '0') .
(6)
Co is normolly 'l', In ihe decimolmode, Co goesto '0' when on outputof
zero (0000)is reochedcountingdownor on output of nine (l 001) is reoched
countingup, therebyprovidingo 'corry'output to the next stoge. In the
binory mode (whenovoiloble)on outpuiof fifteen (l ll l) when countingup
or zero (0000)when counting down couseso '0' ot Co.
CMOS Tronlmission
Gotes
t2.
(f )
gote is shownbelow:The logic symbolfor o tronsmission
SIGNAL
SIGNAL
CONTROL
T r o n s m i s s iG
o no t e
F i g . S u p p ,2 . l 2
(2)
gote is on onologueon/off gote which qllowsd signolto flow
The tronsmission
throughit in either directionwhen o 'l' is oppliedio fhe control line. The
signol moy be onologueor digiiol but mustnot exceedthe volioge limitsof
0V ond VDD.
(3)
Whenthe control line is ot '0' both signol lines ore equivolentto on open
circuit wiih no connectionbetweenthem.
CMOS-TTLBufferGotes
13.
(l)
Thelogicsymbols
for buffergqtesore os follows:-
INPUT
OUTPUT
NON-INVERTIN6
Buffe r Gotes
RA, l77B Mointenonce
OUTPUT
INVERTING
F i g . S u p p .2 . 1 3
Supplement
(2)
Buffergotesprovideo sufficientlyhigh currentoutput for TTL logic when fed
with o CMOS logic input. They moy be invertingor non-inverting'
(3)
A voltoge moy be oppliedto the inpui when no supplyvoltoge is present
the ouiput cousesexcessivecurrentflow ond moy
wiihout domoge' Si'rorting
domogeihe gote.
D^^.
RA. I 778 Mointenonce
Q
Supplement
SUPPLEMENT
3
ALTERNATIV
E G I CS Y M B O L S
LO
INTRODUCTION
The circuii diogromsond in-iext figuresin this hondbookcontoin rogic symbors
drownto two differentstondords.where differenisymborsore rr.dio
r-epresent
ihe someitem, this oppendixidentifiesthe olternotive.
OESCRIPTION
SYVBOLS
U S E OI \ T h J S I - I A N D B O O K
OR GATE
N O R G A TE
EXCLU
S I VE O R
A N D G A IE
NAND GATE
ItoH loirl
R A . 1 7 7 8M o i n t e n o n c e
S u p p t e m e n t3
Poge I
Suppleme
nt 3
SUPPLEMENT
4
I N T R O D U C T I OTNO O P E R A T I O N A M
L PLIFIERS
INTRODUCTION
|.
Inrs oPpendtxprovtdeso brief description of operotionolomplifiers including
typicol opplicoiionsin Rocolequipmeni,
Bosic Properties
V POSITIVE
INPUT
OUTPUT
V NE G A T I V E
BosicOperofionol Amplifier
)
3.
F i g . S u p p .4 . I
Operoiionolomplifien hove the following bosicproperties:(l)
The goin withour feedbockis very high.
(2)
when feedbock is opplied the omprifier orters its output so thot the positive
ond negotiveinputsore ot equol levels.
(3)
The input impedonceis sufficienrlyhigh to be ignored.
Comporofor
(l)
Whenconnectedos in ihe following diogromthe operotionolomplifier
functions os o comporotor.
R2
Rl
INPUI
ComporoiorCircuii
ll
i
i
F i s . S u p p4. . 2
Poge I
RA. l77B Mointenonce
Supplement
4
4.
(2)
With U noi fiifed no feedbockis opplied. Therefore,if the positiveinput
voltoge is greoterthon V ref, the ouipui voltogeswingsio its moximum
Vcc. lf the positiveinpui voltoge is lessthon
positive level, opproximotely
V ref the oulput voltogeswingsto its moximumnegotivelevel, opproximotely
Vee.
(3)
ihe switching
tf R2 is fitled, positivefeedbockis introduced' This increcses
so the circuit octsos o Schmitiirigger.
speedond introduceshysteresis
Inverting(virtuol eorih) crnplifier
(l)
When connectedos in ihe following diogromthe operotionolcrnplifier
functionsos on invertingomplifier:-
F i s .S u p p . 4 . 3
InvertingAmplifier Circuii
(2)
The oufput of the omplifierodiusfsso thdt the negoiive input is ot OV
(see porogroph2(2)). As V in ond V out ore of opposiie polority, ihe current
ihrough Rl equols the current fhrough R 2 .
.H A. h . A
V out
R2
v tn
RT
V out
Vin
KI
RT
Ior
Therefore,the voltogegoin, AV, = ='rKI
(3)
The positiveinput moy be held ot o voltoge other thon zero but oll input ond
ouiput voltogesore then relotive to this, os in the fol lowing exomple:-
+ 2.1V
InvertingAmplifier with Voltoge Offset
RA. l77B Mointenonce
Fis. Supp.4.4
Supplement
SUPPLEMENT
5
R E P A ITRE C H N I Q U E S
INTRODUCTION
l.
T h i so p p e n d i xdescribes,in generolierms, the tools ond moteriolsrequiredond
the proceduresto be followedto focilitote o sotisfoctoryrepoirof the equipment.
TOOLSAND MATERIALS
Tools
2.
(t)
Wire cutters.
(2)
Wirestrippers,
(3)
Pliers.
(4)
Screwdriver
TyP.
Size
(5)
5crewdriver
Type
Size
(6)
Pozidriv
2PT
Screwdriver
Typ"
Size
(7)
Pozidriv
IPT
Flot-bloded
2mm
Screwdriver
Type
Flot-bloded
5-10 mm
(B) Box sponner
Size
5.5 mm, to fii M3 nuts
Poge I
RA,. l77B Mointenonce
Supplement
(9)
Solderingiron
Type
power
Bit moteriol
Bit size
Thermostoiic,280o-3O0oC
50 W
lron Ploted
3-4 mm
(ExomPle:ORY X-50)
(10)
Solderingiron siondond cleoner.
(ll)
Brush,stiff, shori bristle.
Moieriols
3.
(l)
D e s o l d e r i nbgr o i d .
(2)
C l e o n i n gf l u i d .
(3)
Solder
TYP"
Diometer
Resincored
2 2 s' w ' g ' ( 0 ' 5 m m )
Useof Toolsond Moteriols
The iron-ploiedbit of the solderingiron is kept cleon by wiping on o dompsponge
ond it is importontihot the spongeis kept domp. Do noi file the bif; if it hos lost
iis originol shopeii shouldbe reploced.
4.
5.
The desolderingbroid will becomeineffectiveif it is ollowed to corrode; it is
imporiont,therefore,to keep it in o seoledcontoiner'
Do not usethe cleoning fluid in o confinedspoceond toke core not to inhole the
vopour. Aliernotive types of fluid should not be usedos they moy dcrnogefhe
comPonents.
6.
7.
Useonly resin-coredsolderof the correctdiometer; the useof solderihot is too
thick will result in on excessiveomountbeing opplied to the ioint'
REPAIRPROCEDURES
Generol
g.
of the compoctnotureof ihe equipment,core is requiredin the reploceBecouse
mentof componention printedcircuii boords. In porticulor, if o componentis
Poge2
RA. l77B Mointenonce
5
Supplement
incorrectlyremovedfrom o printedcircuit boord, the coppertrock
moy breok owoy fromthe
boord, thusmoking ii impossible
io reprocethe componenisotisfoctoriiy. ThisocJursif
pressure
is opplied to the componentin ihe wrongdirectionwhile the heot
of the soldering
iron cousesthe ioint between.theboordond the coppertrock to weoken;
the ioint wilr not
be remqdeon cooling. The direction in which pressure
shouldbe oppriedto the co.ponent
is.shownin the following diogrom; pressure
mustnot be oppriedin either o ,ia.*oy,
direction or owoy from the copper side of the boqrd.
COPPERTRACK
PCB 8 ASE
ComponentRemovol
: CorrectApplicotionof pressure Fig. Supp, 5.1
Desoldering
9'
Desolderingis occomplished
usingthe.sorderingiron ond the frux-impregnoted
desolderingbroid. Ensurethot fhe sorderingiron hos reoched
irs furiwJrking
temperotureond opply the broid ond the iron to the
os
shown
in the folowing diogrom.
ioint
Do not opply ony sidewoyspressure. Removefhe iron ond the
broid ri61rtton"ouri| from the
ioint or the broid moy becomesolderedto the copper,
O E S O L O E R I NBGRA I O
COPPER
SOLDERE
D
Desoldering
Techn
ique
F i g . S u p p .5 . 2
10.
After removingthe bulk of the solder, cut off onodiscord the used length
of broid
(e. g. 5 to I 0 mm)ond repeotthe 6ove operotionto ensure
thot ony remoining
solderis removed. Cut off ond discordihe usedlengthof broid.
p^^- ?
RA. l77B Mointenonce
g
Supplement
Repeotihe desolderingoperotionon the remoiningleodsof the componentto be
removed, When finished, eoch leod shouldbe free of solderond it shouldbe
possibleto seethe outline of the hole in the printed circuit boord. Llsecleoningfluid
to removeony residuolflux.
II,
RemovingComponents
ond copocitorsore usuollyheld in positionon the prinied circuit boordby
Resistors
'crimp'
on the componentleod, In orderto removethe component,cuf off the
o
'crimped'sectionof the leod with the wire cutters, The componentmoy now be removed;
it connotbe re-usedos the leodsore now too shori.
12.
HERE
C O M P O N E N LTEA D
C O MP O N EN T
Removolof Components
wiih CrimpedLeods
Fis. Supp.5.3
diodesond metol integrofedcircuits usuollyhove two or more wire
Tronsisiors,
bent
over
to hold them in position. Ensurethot the ioint hcr been odequotely
leods
desoldered,then grip the wire with pliers, os shownbelow, ond corefullytwist the wire o
smoll omountoround the hole in the boord. The wire shouldport eosily from the copper
repeotihe desolderingprocessuntil the wire con be moved,
trock; if there is ony resistonce
for
leods
os
necessory.
other
Repeot
13.
C O M P O N E N LEAD
T
COMPONENT
Removolof Comoonentswith Bent-over Leods
t/
F i s . S u p p5. . 4
To removethe component,stroighteneoch leod with the pliers ond withdrow the
found to be serviceobleii moy be re-used.
component. lf it is subsequently
Poge 4
RA. 1778Mointenonce
5
Supplement
l5'
Duol-.in-linei ntegroied,circu
its ore usuofiysecured
by bendingover two reoos,oi
opposite
corners
of thedevice. Desorder
ortth" r"oal
,Lri* ir.,"-'"'1"**,n
the operoiiondescribedin porogrophs
"itr*
I3 ond l4 on the two bend
leods. The inteorqreo
circuitmoy
nowberemoved,
iinecessory
uy t"u"ring*;il
body of the device.
"
,..r'ir#*Jr,J"r'r-"ti, ,n"
Ploted-through
Holes
'i6'
certoin boords, which con be.recognisedby
the presenceof copper trocks on both
sides, hove ploted-throughholes. In oddition
to providingo connectionto o
o pl.oted-throughhole provideson essentiol
connection between the top ond
:::fon*t
botlom coppertrocks. In order to preserve
this connection, o speciol ,;;;l-;;..rr",
which involvesthe destruciionof ri,u
"o.ponu^r,-i, "J"*rro.
17.
Desolderthe.componentleods os described
in porogrophsg to I I . Cut the leods
ond discord the componenr.
l8'
stroighten,eoch
reodon the componenr
side of the boordso thot it
{i1s nli"n,
possrhroughrhe hore, Grip ihe reodfrol-the
. .will
oiher side ;;il;;';""
opply the solderingiron os shownin.ttr"'rotio*i"g
;;;r.r.
Whenihe"freqd feersfree ro
move, corefully pull it throughthe hole.
@ cur aruo
B E N DU P
COMPONEN T
@ a eerv
S O L D E RI N 6 I R O N
@ cnnerulLv W I T H O R A W
C O M P O N E NLI E A O
PLIERS
Removolof Componentsfrom ploted-through
Holes
F i s . S u p p5. . 5
19.
Remove
ony excesssolder with desolderingbroid ond the
soldering iron until both
surfoces
of the boord ond the hole k cleor. Uring
fi;;; ," removeony
residuolflux.
"t.onin;
20.
Ensurethot eoch hole is free from flux ond solcler
before inserting the component
leod. Bendeoch leod over ond cut to length (3
mm); in the coseof duol-in-line
integroted circuits bend over only two leods
in diogonolI y opposite corners.
Poge 5
RA. l77B Mointenonce
Supplement
21 .
Resoldereoch leod of the componentwith thin resin-coredsolder, usinglhe
minimumnecessory
to mokeo sotisfoctoryjoint. Ensurethot the solderingiron ho
ond hold the bit to ihe ioint for two io three seconds.
reochedfull operoiingtemperoture
22.
io opply solderio ihe
Whensolderingon double-sidedboordsii moy be necessory
componentside of the boordio ensurethot solderflows througho ploted-through
h o l e.
Certoin integrotedcircuitsusedin the oudio switchingunit ore of the COS-MOS
type. lhis ty:peof device moy hove on input impedonceof the order of l0l4 ohms
whereosthe breokdownvoltogeof the oxide within ihe device is oboui 100 volts. Since
stotic voltogesof up io 4kV con be generotedby strokingsilk, nylon or certoin plosfic
contoiners,it is essentiolihoi the following precouiionsore token to Preventhigh voltoges
occurringot the leodsof COS-MOS type devices.
23,
(l)
The iips of solderingironsshouldbe eorthedto the eorth plone of the boord
being soldered.
(2)
The devices shouldnoi be stored in plostic bogsor contoiners(unlessthe
plosiic hos beenespeciollytreotedwiih onti-stotic chemicols).
(3)
Operoiorsshouldnot weor nylon or plostic gloves, or rubber-soledshoes'
(4)
As mony leodsos possibleshouldbe 'shorted'wifh ihe fingersduring hondling.
(5)
Do not removethe input connection with the device connectedto the supply
r o i l.
RA. l77B Mointenonce
Supplement