•
FM DATA SHEETS
# 14 MULTI-CHANNEL Ri C EQUIPMENT
THE DIFFERENCE BETWEEN
SINGLE- AND MULTI-CHANNEL:
(
SINGlE- CHANNEL:
TH~TRANSMITTER
SENDS A
27. 55 Me" CARRIER WAVE WHICH
IS RECEIVED AT THE PLANE.
THIS SIGNAL IS CONVERTED INTO A CURRENT
~
WHICH OPERATES A
.
SENSITIVE RELAY.
.~. .".
THE RELAY CLOSES
~o ,
AND OPENS A
PAIR Of ELECTRICAL CONTACTS THAT
OPERATE THE
CONTROL CIRCUIT.
(SEE FM DATA SHEET NO. II FOR
FULL DETAILS)
27.255 MEGACYCLE (MILLION
CYCLES PER SECOND) BROADCAST
SIGNAL IS A COMBINATION OF:
27. 255 MEGACYCLE- CARRIERWAVE IS AT RADIO FREQUENCY
AND CANNOT BE HEARD BY THE
HUMAN EAR.
(I) A 27.255 MC CARRIER-WAVE-SAME AS SINGLE-CHANNEL.
(2 ) AN AUDIBLE SOUND OR TONE .
THE RECEIVER SORTS OUT THE
TONE AND DISCARDS THE 27.255MC.
TYPICAL TRANSMITTER:
15V.
"c" BATTERY"
CONTROL STIC
SWITCH
,
DOWN-----======~
.~-- 27.255 MC CRYSTAL
WIRE
..
CONTROL STICK
SWITCH
--....:.·,'... -""F· SWITCH
"UIVI~I'I ____
RIGHT RUDDER
ENGINE---c::==
LEFT RUDDER
UP
------==:==
FIBRE
BATTERY BOX
(COVER OMITTED
FOR CLARITY)
HOLDS 135 VOLT
"B" BATTERIES AND
1.5 VOLT FILAMENT BATTERI~S .
THE CONTROL STICK IS MOVED TO MAKE CONTAC1 TO '
OPERATE THE DESIRED CHANNEL. ONLY ONE TON~ CAN
BE SENT AT A TIME! NOTE THAT "RIGHT~ "ENGINE·, OR
·LEFT· IS OBTAINED BY PULSING THE CONTROL STICK
BACK AND FORTH UNTIL THE MODEL RESPONDS TO THE
PROPER CONTROL.
TYPICAL RECEIVER:
THE TONES ARE RECEIVEDlONE AT A TIME.! AND
ARE FED INTO THE TONE BOCK WHICH PA:;SES
A CURRENT TO THE RELAY WHICH OPERATES THE
PROPER CONTROL CIRCUIT. NOTE THAT THE
27.255 Me SIGNAL IS ONLY USED AS A CARRIER
TO TRANSMIT THE TONE~. THE RECEIVER WILL
NOT OPERATE ON A 27.255 MC SIGNAL ONLY-CORRECT TONES ARE A "MUST."
THE TONE BLOCK IS AN ELECTRICAL FILTERING
(TUNED) CIRCUIT, AND HAS NO MOVING PARTS.
HARNESS PLUG
RUBBER-CEMENT
SPONGE TO METAL
PARTS
4
SUGGESTED
MOUNTING
·BABCOCK·
SPONGE RUBBER PADS
ALUMINUM ANGLE
BRACKET
FLYING MODELS for February 1955
SLUG TUNER
29
HARNESS WIRING:
~-~
TO THE ACTUATORS
AND CONTROL DEVICES
"B" BATTERY
CONNECTORS
SERVO MOTORS:.
COMPOUND ESCAPEMENT:
THESE ARE AVAILABLE IN VARIOUS
TYPE'S AND ARE COMMONLY USED
TO OPERATE THE ELEVATOR CONTROL. THEY CAN BE STOPPED IN
ANY POSITION BETWEEN MAXIMUM
·Up" AND FULL "DOWN". BECAUSE ,
THEY CAN BE LEFT AT ANY
CONTROL POSITION THROUGHOUT
THE ENTIRE FLIGHT, IF
DESIRED THEY ARE
CALLED "'TRIMMABLE."
THIS IS A RUBBER-DRIVEN UNIT
WHICH SUPPLIES RIGHT AND
LEFT RUDDER CONTROL PLUS
ONE AUXILIARY CONTROL. THE
RUDDER IS ACTIVATED BY THE
CRANKPIN.
SPEED REGULATOR
THE AUXILIARY CONTROL IS HOOKED TO
A PAIR OF ELECTRICAL CONTACTS WHICH
CLOSE EVERY THIRD
OPERATION.
CONTROL ROD--TAKES
2 TO 3 SECONDS TO
REVERSE BETWEEN
"FULL UP· AND "FULL DOWN"
MECHANICAL STOPS
(CHANGING BATTERY POLARITY
CHANGES DIRECTION OF TRAVEL)
BONNER SERVO
THE COMMONEST AUXILIARY
CONTROL IS AN ENGINE
CONTROL AND CUT- OFF.
Jlti,~~~L SEQUENCE OF THIS
BOND
NEUTRAL, RIGHT, NEUTRAL LEF'P,
NEUTRAL, AUXILIARY, NEUTRAL .....
RUDDER LINKAGE,
PUSHROD IS USEQ TO
CONNECT SERVO MOTOR
TO ELEVATOR AoRN
BRASS TORQUE TUBE:--_:-::::::~7
WIRES TO BATTERIES
MOTOR-CONTROL ESCAPEMENT:
THE COMMONEST TYPE
OF ENGINE CONTROL IS
THE'AIR BLEED" USING
TWO NEEDLE VALVES .
IHE CONTROL DEVICE
BLEEDS" AIR INTO THE
HIGH-SPEED OR LOWSPEED FUEL-LINE. THE
VALVES ARE PRE-SET
INDIVIDUALLY.
,
l]I~.a.~ON
GROMMETS
ACCESSORY EQUIPMENT:
AS WITH SINGLE-CHANNEL RIC
EQUIPMENT, IT IS NECESSARY
TO HAVE AN ASSORTMENT OF
MILLAMMETERS AND VOLTMETERS-OR A MULTlt<.1ETER.
A PLASTIC TUNING
WAND IS A "MUST'
FOR BEST RESULTS
ENGINE VENTURI
TO LOW-SPEED JET
HEADPHONES ARE NESSARY TO
TUNE MOST RECEIVERS. THEY
PLUG INTO THE METER-JACK. AN
IDEAL CHECK FOR MIS-OPERATION . •
HIGH-SPEED J T
LOW-SPEED JE
8
-11
TO TANK
OPTIMUM PERFORMANCE RESULTS WHEN ALL OF THE
METAL PARTS IN THE MODEL ARE BONDED TOGETHER
ON A COMMON GROUND, EXCEPT ANTENNA!
11
BATTERY TEST:
WHEN TESTED IN THIS
MANNER, THE
VOLTAGE ;:,n'IUL.,m
DROP TO LOWER
,r====;~llilb!6~2~
.5:'VOLTS. TEST
~
5TOI0
SECONDSI
3000 OHM-- 2 WAT
RESISTO.R
WIRE THE ENGINE, LANDING GEAR STRUTS, ACTUATOR CASES AND
PUSHRODS, CONTROL HINGES, RECEIVER BASE, ETC. TO BONDING STRIP.
30
FLYING MODELS for February 1955