I
The Heathk it $8·110. A slide-r ule scale at the top of the
dia l escu tcheo n refe rs to the SO kc poin ts ove r a 500 ke
ra nge, while the circulor scale is line a rly ca lib rated in
1 kc steps. The fi ducial hairl ine may be a d justed for
cal ibra ting purpOl.e, by mean , of the small kno b on t he
upper right of the escutcheon .
CQ Reviews:
I
T he H eathki t SB-110 6-M eter
S.S.B. Transceiver
BY WIL FRED M. SCH ER ER ," W 2AEF
of Heathkit' s newer units in their popular "SH" series is the SH·) )0 transceiver
which in one package, (less power supply), pro vides full coverage on the 6-meter band
for fixed-station or mobile use on s.s.b., c.w. or
a.m. (s.s.b. with carrier). Yo u don't need any accessory trapping- translators. converters. li near
am plifiers o r what -have-you , usuall y used with
present gea r to get on 50 mc s.s.b,
Delivering 100 wa tts p.e.p. o utput with stable
acc urately ca libra ted v.I.o. frequency co ntro l
ove r the en tire 50-54 mc range, the 5 8- 110
shou ld set a new standa rd for this band . Let us
take a loo k at some of its other feature s and specification that might put it in this category: Sideband generatio n and receiver selectivity obtained
wit h a h.f. 2.1 kc crystal filter; Nuvistor fro nt end
with sensitivit y of 0.1 p'v for 10 db s./n . rat io ;
preselector tuning; a.g.c.; autom atic rece iverfre quency offset for c.w. operat ion; bu ilt-in crystal calibrator; v.f.o. stability 100 c.p.s. per hour ;
c.w. side tone mon itor; headphone level control;
p.t.t. or built-in v.c.x.; V.O.x. type break-in for
c.w. phone-patch input; upper or lower sideband
operation; adjustable pi-output for 25-100 ohm
load s: crystal-control operation for transceive or
for transmitter onl y; panel meter cali brated in
S-units or transmitter funct ions (plate. a.l.c. or
relative power output ); and an effective noise
limiter. a feature missing on mo st s.s.b. transceivers. There are two power suppl ies available.
one for 120 v, a.c. operatio n. the other for 12
v, d.c. mobile use.
Like most Heathkit products, the S8 -11O
comes in kit form , en abling you to have the fun
and sa tisfactio n of putting your own gear together at a substantial saving in cost over factorywired equi pment. Alt hough the set a ppears to be
quite com plicated. it is not as difficult to bui ld as
one might expect. This was borne out by an exNE
O
"Technica l Director, CQ.
periment we tried; namely, turn ing the kit over
to a novice to do the work. Happily this turn ed
out to be a successful proposition from wh ic h a
few good lessons were learned.
Receiver Sect ion
A bloc k diagra m for th e Su- t t 0 is shown at
fig . I. Double conversion is used for th e receiver
wi th the first conversion o f 8.4-8.9 me obtained
hy heterodyning the input signa ls with a separate
crysta l (4 1.6-45. 1 me) for each 500 kc band segment. T he second i.f. is at 3.395 me, obtai ned
by mixing the 1st i.f. signals with 5.0-5.5 m e signals from the v.f.o. Side ba nd selectivity is obtained wit h a 3.395 me crystal fi lter and the signal is converted to audio by a p rodu ct detecto r.
The r.f. stage is a neutra lized 6DS4 Nuvistor ,
coupled to the m ixer, ano ther 6D54, th rough a
double-tuned narrow-ba nd pass circuit which,
instead of being broad banded with fix-tuned circu its. is resonated by a three-gang variable ca pacitor to pro vide "preselector tuning:' Th is arrangement ensures better cross- modu lation
characteristics and maintains peak sensitivity
with minimum noise over the full range.
The 804-8.9 mc band pass cou pler after the lst
mixer rejects all frequencies outside of this range,
and an 8.5 mc trap in the anten na circuit rejects
input signal s at the Lt.
The product detector is a ring-type "balanced
modulator" affair using four diodes, a method
we've always found superior for exceptionally
clean s.s.b. demodulation.
Sidebands are changed by switching the b.f.o.
frequency to either skirr of the filter. \Vhen this
is done. the frequency of the v.f.o. is auto matically shifted 10 eliminate retun ing. This is accomplished with the sideband selector whic h activates
a diode switch that cuts in a ca pacitor, shifting
the v.f.o. during l.s.b. operation.
For crystal-controlled net operation or work
Ma y, 19 66
•
CO
•
S9
on MARS frequencies the v.f.o. ca n be cut out
with an OSCILLATOR-MODE switch, substitu ting a
built-in crystal oscillator. Crystal-control is thus
obtained on the sa me freq uency for both receive
a nd tran sm it. Another switch position provides
crys ta l control for the transmitter only, with
v.f.o. tuning retained for the receiver. An excellent feature is that the crysta l oscillator has a
trimmer to perm it ad justing the crys tal to exact
frequency.
The set is supplied with four crysta ls for the
heterodyne oscilla tor to cover 50-52 me . For use
at the top half of the band and for MARS wo rk
below 50 me, addition al heterod yning c rys ta ls
are required .
The automat ic noise limite r, one of the best
for s.s.b .. is a n Lt. type utilizin g a pa ir of silicon
diodes in a full -wave circuit shunted across the
last i.f. tran smformer.t An on-off switch is included.
Besides the customa ry a.f. ga in contro l, there
is a separate sc rewdriver-ad just control to vary
the high-impedance o utput level for comfo rtab le
headphon e listen ing without changing th e normal
loud speaker level.
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May, 1966
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' '' IF N L''- A n 5 .S .8 . I. F. Noise Li m iter, CQ. June '60,
p. 42.
Fig. l -Block diagram for the $ B·110. The receiver routing is sh own with solid connections, the tran smitter
sect io n is connected by dash ed lines . Elements common to both tronsmitter and receiver are mark ed with
an asterisk.
._--
--
--- - - - - - - - - - -
The c.w. carrier is obtained from a 3394.4 kc
crysta l oscillator and is injected at t he isolation
a mplifie r. the gain of which can be adjusted with
a DRIV E-lEVE L control to p roduce the required
power level for the final a mplifier. The C.W. carrier frequency is 800 c.p.s. higher than when th e
receiver is used in the u.s.b. position. This provides " freq uency offset," so that when the receiver is tu ned for an 800 cycle beat no te on a
c.w. signal, the transmitter will automatically be
zero beat wit h the signal for on-frequency operation.
Assembly
Exce pt for the fi na l am plifier and the v.f.o.,
all stages a re bu ilt o n fi ve p rin ted -ci rcu it boards.
Th is sim plifies the wo rk wh ich is furthe r m ade
easier wit h a p rea ssem bled , factory- wired and
a ligned v.f.o. A fte r the circuit board s have been
assembled and installed a lo ng with other chassis
components, the major pa n of the wo rk consists
of interconnecting the board s and panel controls.
There a re two preassembled colo r-coded harnesses provided for the job.
It took our neophyte 42 ho urs to p ut the
5 8-110 together. Several additio na l hours were
required on our pa rt to do som e trouble shooting before the rig wa s al igned and workin g
pro perl y; all due to the fact that although the
step- by-step instructio ns were clear and simple
enough. our " eager beaver" was too hasty, ad mittingly neglectin g to carefu lly read a nd correctl y follo w t hrough with so me of the ste ps . He
also. no dou bt, tired by doing the work in the
eveni ngs ove r st retch es o f 4-6 ho u rs a t a time .
We therefore cannot em p has ize too stro ngly
the necessity for tak ing enough time to study
each assemb ly step thorough ly a nd to " th in k it
th rou gh" before proceed ing. A lso, do not work
more t han 1-2 hours at a clip, in order to m in imize the cha nce of errors due to fatigue. Remember the o ld ad age, "hast e makes waste!"
These suggestions apply to any kit work whether
it be simple or complicated, and regardless of
whether you're a newcomer or a n o ld hand .
/
Performance
Let us now take a look at the results obta ined
with the finished p rod uct. The receiver sensitlvity fo r the S B·110 was better than usually found
with 6-meter gear, measuring within the rated
0. 1 uv for 10 db s./n. a nd could be maintai ned
over the wh ole ba nd . Strong-signa l hand ling
capabili ties also were exce lle nt.
The follow ing o ther mea su rem en ts were up to
specifications, except as no ted : SELECTIVITY: 2. 1
kc a t 3 db, 5 kc a t 60 db; UNWANTED-SIDEBAND
S UPPRESSIOS: 55 db; IMA.GE R EJ ECTiON: rated
at 50 db. 48 db ; I.F. S,GNAL R EJ ECTION (8.5 me ) :
rated at 50 db. was 60 db; at 3.395 me. 80 d b
(not rated); INTERNA. L SPURIOUS R ESPONSES:
rated at 0.1 p V equiva lent signal , except 0.3 IAV
at 51.250 mc -none was found in the 50-52 m c
range except the specified one (crysta ls were not
su p plied for the upper half o f the band ) .
\ Ve often marvel a t the overall frequency sta-
_.....
To p view of the S&- 11O. The v.Le. is at the upper center .
The fino l is shown " uncove red" a t the lower left. Th e
other sta g es are assembled on the various printed ·
circu it boards.
bil ity and calibration in the H ea thk it Sa-series of
gear of which the S8·11O is typical. The stabilit y,
rated at less than 100 c.p.s. drift after 20-minutes
warmu p a nd less than 100 c.p.s. for + 10% s uppl y-vo lta ge variation , was 250 c.p.s. after 10 minutes warmu p, 80 c.p.s. the nex t hour a nd 40
c.p.s. per hour o r less the reafter. Li ne vo ltage
variation o f ± 10 % p roduced ± 70 c.p.s. change .
In addition, mechan ical stabil ity as may be
encountered in mobile ser vice, was such tha t no t
a whimper of frequency twitter or m icrop hon ics
was evident when the set wa s dropped an inch o r
so above the table.
The dial. (wh ich has an adj usta ble h airline
[Continued 0 11 page 100]
•
•
.. .
.. -
•
I
I
•
Bottom vie w of the SS-110 . Wiring for the grid side
of Ihe final is done in the partitioned seclion a t the
upper left. Most of the o ther wiring is mode using
two hornesses.
Ma y , 19 66
•
CQ
•
61
ville. Send G C R (G e nera l Certificatio n Rulecertified by Club Officer or two other licensed
amateurs ) and $ 1.00 to Amat eur Rad io C lub of
Florida. Box 73 26 Eucl id Stat ion. 51. Petersburg.
Florida 33734. If co ntacts are all v.h .L, vvo rk
only 8 cities. A vailable to s.w.ls on heard basis .
This is very bea utifu l awa rd Art Designed in
two color and printed o n Sem i-Gloss paper.
J. A. R. S. Twenty-Ftffh Anniversary Award: In
conjunction with its 25th Ann iversa ry celebrated
during 1965. Th e J oliet Am ateur Radio Socie ty
l\V90F R). is issuing a ceritficate to anyone who
worked \ V90F R dur ing 1965 . Anyone wh o
worked W90FR du ring 1965. especially o n F ield
Day or o n o ne of o ur "on th e air" sessions fo r the
25th Anniversa ry Station during Septembe r. October and Novem ber. we are ver y anxious to
collect QSL ca rds. so please send your QSL a nd
a s.a .s.e. for th is " wa rd to. Jol iet Amateur Rad io
Society, c /o J im Rainfo rd. WA9K PW, 813 Fisk
Ave., Jo liet. Illino is.
Sure glad th at J A7C E K finall y got h is Ma rianas A mateur Radio C lub Award. It seems that
his first a pplication was lost but it took about 7
months for the award to be issued from the a pplica tion that ~I ARC acknowledged receiving. •md
Ihis afte r much pressure from severa l California
sta tions.
An apology to W7DZ B as by error his called
was listed as W7J ZH in the December fu ll list of
USA-CA A ward holde rs.
Don't kn ow who se nt it but I enjoyed the card
for m y recent birthday whic h was add ressed:
To the "HAM " of Sta tio n H-O·P-P·E-R who
sparks from 10 3 wa lts on Wh itman St.. Rochelle
Park . Note o n it read: Happy Sparking to a swell
Ham & Cheese o n Rye. From an O ld Crystal
Set. Also a drawing of a lower and crysta l set
o n the card. and a pho to of a dog with big ears.
a nd my n ickn a me used to be "big ears." not because I' m another Clark Gable. but I was prett y
good at digging out the weak /rare signals. Or
does the sender (1) think I' m a dog? H i. ..•
Anyway, T hanks. Ho pe you got some of those
needed QSLs and counties. write and let me
73. Ed.. \V2G T
know, how was your month?
Ham Clinic Uro", page 80J
Frequency D rift Measurement- "\Vhat do you
suggest is the best way to measure frequen cy
drift? I have a rece iver that I would like to
stab ilize once a nd for all. Any hints?"
Try to borrow a frequen cy counter such as
is made by Hewlett Packard . Be sure not 10 confine your drift measurement s to o ne band or onl y
one or two frequen cies within a band-cycu'Il fi nd
that the drift will va ry accord ing to frequency.
If you can't locate ;1 cou nte r. then you will need
;1 good sta ble heterod yne frequency meter. \Vith
both the rece iver a nd meter warmed up good
(48 hours or more). put the met er and set on th e
sa me frequenc y. Then let both alo ne for a couple
of ho urs. Now come had. a nd re-zero the met er
to the receiver frequen cy. If yo ur dial can he
read closel y, you plot the diDu t"IIce freque nc y
on a chart. Do th is for many frequencies. At the
100
•
CO
•
May, 1966
e nd . yo u' Il have a good idea of the a mount a mi
du rat ion o f drift. The counter is easier thou gh.
Thirty
Readers <Ire req uested to make th eir let ters
short a nd 10 the point. Alwa ys incl ude two IRe 's
or 251' for airmai l postage from ou r present
ove rseas add ress. 4 Lutzel matt St. Luzern. Switzerl and . If you are in no hur ry. then send you r
lett ers to me a t CQ. w e shall do the best we
can to answer you r questions; but please rem ember we ca nnot a nswer them a U- for jf we could
we would no t have to work for a living. Your
kind leite rs a nd cards com menting on H A~I
C LI :"IC are a lways a pprecia ted, believe me. To
those of you who have asked many times if a
H "M C LI NIC Anthology is corning-the answer
is yes .•. we hope you' II buy a copy.
73, Ch uck, W6QLV
The RPHT55R [fro", page 30 ]
a five watt transce iver, Jeep mobile. in the old
home town. What a test! Th is would be the
supre me effort. \Vith the add itional gain sett ing
ba rely cracked he wa s extremel y d ifficult copy
on kilowatt alley. We called and listened with out
result. we ca lled again and advanced the gain.
No result. A th ird call and up went the additional
gain control even more. Contact! ! Conditions
were bad-he was fadi ng. Up went the additional
gain control even more. J ust abo ut Q5 copy now.
maybe a lill ie bit less. Th is had to be it. We
cracked her wid e open and just barely ducked
aside in time to a vo id a hurtling jeep tha t ca me
screa mi ng right through the loud spea ker co ne
a nd into the room . Brea thless a nd sha ke n we
sna pped off the switch and hastily pen ned a note
to ourselves. T H IS RI G M UST NOT BE
O PE RATED UNT IL T HE I.P.S. IS i NSTA LLED.•
»Edttor's no" : T he Idio l Proof Switch wa s insta lled and
man's pro gress o ut o f the dept hs res umed . W e are
currentty negot ta rin g p ub lish ing rights for tho se other
amazi ng d evelopment s.
Heath k it 58·11 0 [from page 61]
for ca libra ting). has I kc divisions spaced a little
over ~ .. a pa rt, permitting visual interpolation to
about 200 c.p.s. The electrical accuracy obtained
from the dial read ing is rated a t within 400 c.p.s.
after calibration at the nearest 100 kc point. Th is
averaged with in 250 c.p.s. even with only on e
ca lib ratio n indexing nea r the center of the v.f.o .
ra nge. One revolution of the tuning knob coven
abo ut 25 kc. making tuning easy. Dial backlash
was well within the rated 50 c.p.s.
Transmitter Pe rfor m a n ce
With a power-line inp ut of 120 v.a.c., the
tra ns mitter power o utput was 95 walts on c.w.
(steady sta te- ra ted at 90 watts). 105 walls p.e.p.
on s.s.b. and a .m., with a 52 wall carrier (ratings
are 100 a nd 50 walls respectivel y). Sideband suppression was sa me as on receive. carrier suppression was a t least 55 db down .
The 58·110 has been in regular use on the
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M I DWA Y AN T EN N A
•
A C· S
•
Kear ney. Nebr n ka
. pleuou.
10 2
•
CO
•
May, 1966
ai r by one of our local 6-meter enthusiasts who
is also a contest competitor. On-the-air reports
indicate excellent s.s.b. qual ity. while the sensitivity. stabi lity, ca libra tion and the no ise limiter
are part icularly su per ior features. v .o.x. operation was found to be good, except with the lowerlevel m icrophon es where the v.o.x, ga in was
margin a l. Cvw. keying is every bit as good as that
commo n on the lower-frequ ency bands as lon g
as good li ne voltage regulation is ava ilable, otherwise a fre quency "lilt.. will be noted. The sidetone mo nito ring is a hand y fea ture, althou gh
there is some tone leakage that a ppears as a
low-level backwave.
Since there are no pro visio ns for norma l a. rn .
detection with the b.f.o. turned off, such signals
have to be read by tuni ng the receiver to exact
zero bea t with the a.m . carrier. Alt hough good
demodu la tion ca n be obtai ned. occasiona l retuning may be req uired , should th e n. m. sig nal drift
or if one or more a.m . sta tions in a rou nd-tab le
QSO are not all on the exact same frequ ency.
The SB- 11O measures 6%" X I·H's" X 13%"
(H. X W. X D .) and weighs 17 lbs. T he kit is
priced at $320.00. O perating voltages for th e un it
are obtained separately from either the HP-23
120 v.a.c. power supply for fixed-statio n use or
from the HP-1 3 transisto rized 12 v.d.c. uni t for
mobile service. Th e H P-23 measures M4" H. X
·H4·· \V. X 9" L.. weighs 19 Ibs. and it is pr iced
at $39.95 {kit). The H P-13 measures 7-1<\" W. X
7')16" L. X 2% " D., weighs 7 lbs a nd is priced
at $59.95 (kit). A sepa rate loud speaker also is
required. The produ cer is The Heath Compa ny,
- W2A EF
Bent on Harbor. ;\I ich.
Audio
Urom page 48]
characteristic. Note that if a n input signal o f 0 db
( I mv) is put into the device. there is an am plification of about 12 db. The same holds for all
levels up to about 14 db (5 rnv input). bu t above
this level the gain starts to decrease. For instance
with an input level of 28 db (25 mv) the amplifi catio n has d ro pped to 8 db . From this point on
the amplification decreascs- (finall y becom ing
negat ive if we carry th e curve farther to th e
right). so th at the ou tpu t level ca n never exceed
abou t 70 rn v, no matter how much is put into
the input. Yo u can see that the objective of amplifying low levels and ho lding down high leve ls
mentioned earlier is ach ieved. \Ve don't get so methi ng for nothing. however. Some distortion is
introduced in the process. For instance. a voice
com ponent at 500 cycles. when clipped. produ ces
harmonics at 1000 and 1500 cycles. which are still
with in the passband . T his type of d istortion is
held to a minim um by the fi ltering in the o utput.
When you're way down in the mud and trying to
get a message across, the listener doesn't m ind the
distortion. and if at th e other ex treme. you have
a good signa l in his re ceiver, you do n't need d ipping, so the device should be turn ed .off. You
can't make a good circuit much belter, but when
the going is rough. a little 3ud io sha ping and
the use of a noise-ca ncell ing mike will make the
• difference between a QSO and none at all.