Hammarlund FM50A Manual

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VHF RECEIVER TRANSMITTER
MODEL FM50A
MANUFACTURED BY THE HAMMARLUND MFG. CO.
Established 1910
INSTALLATION AND SERVICE MANUAL
MARKETING & DI~TRIBU1·ION
OUTERCOM ELECTRONICS CORP.
502 Charlottetown Mall
Charlotte, North Carolina
Telephone 333·8689 Area Code 704
Cable Address
"outercom"
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FRONT
VIEW MODEL
FM-50-A
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FM-50-A TECHNICAL SPECIFICATIONS
Frequency Range:
Transmitter:
FCC File #
Power Output into 50 ohm load:
Duty Cycle:
Crystal Multiplication:
Frequency Stability:
Modulation:
Modulation Limiting:
Audio Response:
Distortion:
Spurious & Harmonic Radiation:
Hum & Noise:
Receiver:
Frequency Stability:
Sensitivity:
Selectivity:
Spurious Response Attention:
Intermodulation Spurious
Attention:
System Audio Response:
Audio Output:
Hum & Noise Level
Squelch:
Duty Cycle:
Crystal Frequency Formula:
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147 to 174 Mcs, on any single channel (not necessarily
the same for receiving and transmitting)
Hammarlund Type FM-50-A
117V AC operation, 35 watts (00%)
12V DC operation, 30 watts (±10%)
6V DC
operation, 20 watts (±10%)
117V AC - 1 min. on, 1 min. off
12V DC - 1 min. on, 4 min. off
6V DC - 1 min. on, 4 min. off
Twelve Times 0
0.0005% (_300 to + 60 C ambient temperature range)
OVEN CONTROLLED
16F3, ±5Kc deviation for 100% modulation at 1000 cps
Instantaneous and automatic, . 25V rms input at 1000 cps
for thresh-hold of limiting
+1 to -3 db from 300 to 3000 cps, 1000 cps reference
Less than 10% at 3.5 Kc deviation, 1000 cps modulating
frequency
At least 60 db down
At least 40 db below ±3. 3 Kc deviation, 1000 cps reference
See transmitter specifications above
0.5 microvolt or less for 20 db quieting
±5 KC (or greater) at 6 db down
±17 KC (or less) at 100 db down
At least 90 db down
At least 65 db down
±2 db from 300 to 2500 cps, 1000 cps reference
At least 1. 0 watt at less than 10% distortion into built-in
speaker
Squelched, at least 50 db down from rated output
Unsquelched, at least 40 db down from rated output
Signal to noise ratio type, front panel adjustable,
. 15 microvolt or less at thresh-hold
Continuous
Signal Frequency -10.7 MC
3
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Tube Complement
6BS8 Receiver
Cascode RF Amplifier
6BR8
1st Oscillator/Multiplier and 1st Mixer
"
6BR8
1st IF Amplifier (10.7 mc) and Squelch Noise Amplifier
"
6BR8
2nd Oscillator and 2nd Mixer
"
6BH6
2nd IF Amplifier (1. 65 mc)
"
6BH6
1st IF Limiter
"
6BN6
2nd IF Limiter and FM Detector
"
12AX7
1st Audio Amplifier and Squelch DC Amplifier
"
6AQ5
Audio Power Amplifier
"
6BR8
Transmitter Crystal Oscillator and Phase Modulator
6AW8A
Buffer and 1st Frequency Multiplier
"
6360
2nd and 3rd Frequency Multipliers
"
6146
RF Power Amplifier
"
12AX7
1st and 2nd Audio Amplifiers
"
Semi-Conductor Complement
IN 2482
Receiver Squelch Rectifier
(2) 2N 442
Power Supply Switching Transistors
(8) IN 1490
Power Supply High Voltage Rectifiers
IN
1490
Power Supply Relay Rectifier (AC Operation Only)
(2) IN 2482
Transmitter Modulation Limiters
Power Requirements:
-.
Nominal Input Voltage
117 volts
6V DC*
12V DC*
(50 to
400 cycles)
Receiving-Standby 50 watts
11. 5 amps 5.75
amps
Receiving Ready to Transmit
70 watts 15
amps
7.5
amps
Transmitting
175 watts
25 amps
15
amps
Intermittent Xtal Oven Drain
4 watts
.6 amps 1.2
amps
SIZE
13" wide, 7" high, 7-3/8" deep
WEIGHT 21lbs. less antenna and power cables
* DC voltage tests are made using Electronics Industry Association Standards which are;
a) For 6 volt systems, standby voltage is 6. 8V DC and transmit voltage is 6. 3V DC.
b)
For 12 volt systems, standby voltage is 13. 6V DC and transmit voltage is 13. OV DC.
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DESCRIPTION
1"-"
The FM-50-A is a rugged, compact communications unit designed to operate from any
6 or 12 volt d. c. (negative or positive ground) vehicle power source or a 117 volt a. c. 50 to
400 cycle land station power source.
The FM-50-A is designed for narrow-band phase/frequency modulation (±5KC deviation)
operation in the frequency range of 147 to 174 megacycles. The receiver and transmitter sections
are designed for single channel, crystal controlled operation. The transmitter and receiver may
be operated on the same channel (as in the business radio service) or on different channels (as in
the taxicab radio service).
All necessary components for 6 or 12 volt d. c. operation of either polarity or 17 volt
AC operation are built into the basic communications unit. The proper circuitry is selected
by the wiring of the external power plug thereby eliminating the need for jumpers or switches
in the basic unit. The FM-50-A may be interchanged in any 6, 12 or 117 volt system without
modific ation.
OPERATING INSTRUCTIONS
Control Functions: There are only three external controls. The left knob is a con-
ventional volume control; the right knob controls the squelch. By turning the squelch knob
clockwise, the sensitivity is increased and as this control is advanced clockwise, a point will
be reached beyond which a loud hiss will be heard. However, there is a setting before this
point where the receiver is operating at optimum sensitivity in a squelched (noiseless) condition.
The three-position power switch on the panel is "OFF" in the extreme left setting. In
the center, or "STDBY" position, the receiver only is operating, and the transmitter filaments
are turned off. In the "OPERATE" position, the receiver remains "ON" however the trans-
mitter filaments are also "ON". After a warm-up period of about 20 seconds, the transmitter
is ready for operation by depressing the "push-to-talk" switch on the microphone.
The "on-off" pilot lamp located to the left side of the power switch lights when the set
is turned on. The pilot lamp on the right side lights only when the transmitter is on the air.
When the push-to-talk microphone switch is depressed, the transmitter section of the
communication unit is actuated, the red transmit lamp lights and the receiver is muted.
Release of the push-to-talk switch, turns the transmitter section off, extinguishes the red
transmit lamp and actuates the receiver section. This sequence of events is in the "OPERATE"
position of the power switch. When this switch is in the "STDBY" position the microphone push-
to-talk circuitry is inoperative.
The use of the "STDBY" mode of operation is highly recommended where long periods
of listening only is expected as lower power drain together with longer transmitter tube life
will result.
The FM-50-A is a highly efficient receiver-transmitter and will provide reliable com-
munications over great distances if properly used. Radio operating is an art that is easily
learned with practice.
The limitations of a system installation in any particular area can be learned through
use. Every system, regardless of the frequency or power, will have some locations where it
is not possible to communicate. However, within its range, trees, buildings, small hills and
similar obstructions will have little or no effect on communications. The range of a system is
dependent on a few important factors, such as location and height of base station antenna power,
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and nature of surrounding terrain. The use of a high gain type of antenna at the base station is
highly recommended in all installations for best possible performance.
Assuming that the most efficient installation of the FM-50-A is made, one important
consideration remains. This is correct operating procedure and a few important notes in this
regard are:
L Before transmitting, listen to the receiver and make certain no one else is on the
channel.
2. Let the mobile operator get in the practice of calling the base station for instructions.
Since the base station is in a known, fixed location, the mobile operator can call when he knows
he is in a good location.
3. Show each mobile operator how radio actually helps him in his work by eliminating
doubts about delivery, reducing unnecessary travel, etc.
4. If you are trying to contact a mobile unit from the base station, remember that he
may be in a poor radio-location, he may have both hands busy in heavy traffic, or he may have
stopped in the local diner. If you do not contact him after one or two quick calls, wait a few
minutes before calling again.
5. Keep messages short and brief. Know what you are going to say before you depress
the microphone button. Many 100 word discussions can be reduced to 10 word messages by
thinking and planning before going "on-the-air".
6. Adopt a system of routine and preventative maintenance with your serviceman.
7. Become familiar with the F. C. C. rules and regulations concerning operation of two-
way radio for your particular class of service.
Transmitter Tune- Up Procedure:
CAUTION - The plate capacity of the 6146 output stage is "hot" at all times when power
is turned ON. This applies to both the "STANDBY" and "ON" positions of the power switch.
The transmitter duty cycle is one minute on, four minutes off; therefore, all adjustments
should be made as quickly as possible, keying the transmitter only when ready for actual adjust-
ment or measurement. To minimize interference, on-the-air testing (with antenna connected)
should be kept to a minimum. The use of a 50 ohm dummy load is recommended for all but the
final on-the-air use of the equipment.
If extended periods of testing and/or servicing the exciter stages of the transmitter are
required it is recommended that the lead connecting R150 and R151 be opened. All tests up to
and including the grid of the final stage can be made.
Test Equipment Required:
1. 0-100 micro-ammeter (2000 ohm internal resistance) see page 21 for recommended
test meter circuit.
2. RF wattmeter with 52 ohm dummy load.
3. Modulation deviation meter.
4. Frequency meter with an accuracy of at least. 00025%.
(a) With a
0-100 micro-ammeter connected from terminal 2 of J105 to ground (terminal
11) adjust L118 for maximum indication. (position 2 of recommended test meter)
(b) With the micro-ammeter now connected from terminal 3 of J105 to ground, adjust
L1l7 for maximum indication. (position 3 of recommended test meter)
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(c) With the micro-ammeter now connected from terminal 4 of J105 to ground, adjust
L1l6 and L1I5 for maximum indication. (position 4 of recommended test meter)
(d) With the micro-ammeter now connected across terminals 5 and 7 of J105, adjust
C159 for maximum indication. The value of shunt R153 is such that a micro-
ammeter with an internal resistance of 2000 ohms will actually read 10 milliamperes
at full scale. When making this adjustment, a minimum of 2.5 milliamperes should
be obtained. (position 5 of recommended test meter)
(e) With the micro-ammeter connected across terminals 9 and 10 of J105, C154 and
C153
should be adjusted for maximum radio frequency output as indicated on the
dummy load. The value of meter shunt R149 is such that the micro-ammeter will
read 200 milliamperes full scale. When making this adjustment, the final plate
current should not exceed a value of 160 milliamperes. Excessive loading as indi-
cated by abnormally high plate current may be corrected by increasing the spacing
(decrease coupling) between L1l2 and L1I3.
(f) Neutralization should be checked by removing the crystal from its socket Y201,
With the crystal removed, the grid current of the final radio frequency stage should
be zero. Rotating the plate tuning condenser C154 should not produce any grid
current or radio frequency output. This test should be made with the final stage
shield in place.
(g) Mter making the above adjustments, the transmitter frequency should be set against
a known standard. This adjustment is C183 associated with the crystal oscillator
stage V1I3A.
(h) Mter making the previous adjustments the deviation should be adjusted by applying
a 1000 cycle tone of 1. OV rms amplitude to the microphone connector J104.
Potentiometer R172 should be adjusted for ±5 Kc deviation as indicated on a devia-
tion meter. This adjustment should always follow step (g) above.
CRYSTAL MULTIPLICATION
The following information is listed as a guide which will be helpful when retuning a
transmitter from one end of the band to the other.
Crystal Frequency, L118
2X
Crystal Frequency, L1l7
6X Crystal Frequency, L115/L1l6
12X Crystal Frequency, C159/C160
12X Crystal Frequency, (Carrier) C153/C154
NOTE -When retuning the final stage it is suggested that a lOOK, 1 watt resistor be temporarily
in series with R150 and R151 to limit the plate dissipation to a safe value. A power output of 5
to 10 watts should be achievable when C159, C154, and C153 are properly resonated.
COMPLETE RECEIVER ALIGNMENT PROCEDURE
TEST EQUIPMENT REQUIRED:
1. 0-100 micro-ammeter (2000 ohms internal resistance).
2. DB audio output meter.
3. Low frequency signal generator covering 1650 KC and 10.7 MC.
4. High frequency FM signal generator covering 1363 to 174 MCS.
1. (a) Connect a 1650KC signal to pin 9 of V104A.
(b)
Connect micro-ammeter from J105 pin 3 to ground. (position 3 of recommended
test meter)
(c) Adjust top and bottom of T104 for maximum indication.
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2. (a)
Connect micro-ammeter from J105 pin 2 to ground. (position 2 of recommended
test meter)
(b) Adjust top and bottom of T102 and T103 for maximum indication.
(c) As each adjustment is brought into resonance, the output of the signal generator
should be decreased so as to produce a meter reading between 25 and 75 micro-
amperes. This precaution is necessary so as to eliminate the possibility of
overload which will result in false peak indications.
3. (a) Connect a 10.7 MC signal to pin 1 of V102A.
(b) Leave micro-ammeter connected to pin 2 of J105. (position 2 of recommended
test meter)
(c) Adjust L106, L107 and L108 for maximum indication observing step 2(c) above.
4. (a) Connect micro-ammeter from pin 1 of J105 to ground. (position 1 of recommended
test meter)
(b) Adjust L103 (oscillator) for maximum indication.
5. (a) Connect signal generator on signal frequency to antenna terminal, J102.
(b) Connect micro-ammeter from J102 pin 2 to ground. (position 2 of recommended
test meter)
(c) Adjust T101, ZF101 and L105 for maximum indication observing precaution outlined
in step 2(c).
6. (a) With
an input signal of approximately. 5 microvolt, touch up T101, ZF101, LI05,
LI06, LI07, LI08, TI02, TI03 for maximum quieting. This will approximate the
same resonance points as maximum 1st limiter grid current indication.
7. (a)
Adjust L109 for maximum hiss level keeping the front panel volume control below
the overload point.
(b) With an on-channel frequency modulated signal applied to the input of the receiver,
readjust LI09 for maximum recovered audio.
8. (a) Loosely couple an accurate 10.7 MC signal to the grid of V102A (Pin 1) and adjust
LI03 for an aural zero beat indication in the loud speaker with an on frequency signal
applied to the antenna input terminal J102.
(b)
With the same unmodulated input signal follow step 6(a).
(c)
Adjust the FM detector coil LI09 as outlined in steps 7(a) and 7(b). In lieu of this
technique the modulation of an "on-frequency" base station or mobile transmitter
may be used. In this instance LI09 should be adjusted for maximum audio consistent
with lowest distortion.
It is highly recommended that the service technician make a few practice runs on a
normal operating unit. With a little practice the alignment may be accomplished in
less time than that required to read the procedure outlined above.
RECEIVER ALIGNMENT PROCEDURE. FIELD SERVICE
The "Complete Receiver Alignment Procedure" will rarely be required in the field how-
ever it should be reviewed in order to become thoroughly familiar with the receiver section of
the unit. Receiver field alignment should be accomplished as follows.
9. (a) With an input signal (unmodulated) strong enough to produce approximately 20 db
quieting of the thermal noise (hiss) adjust LI08 to zero the first oscillator with
the incoming signal as outlined in step 8(a).
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NOTE: In lieu of the use of a 10.7 MC signal, L10S may be adjusted in the center of the
range over which quieting sensitivity falls off. It is extremely important when making
this adjustment that the incoming signal be on frequency.
9. (b) Perform step 6(a) above.
CABLE INSTALLATION
Certain precautions must be observed when installing the FM-50-A. It is very important
that polarity be observed on vehicle installations. Using the power cable chart, at the rear of
the manual, first, determine which cable is to be used. In most installations, you will find that
modern vehicles employ a 12 volt negative ground system, therefore, be sure to use the cable
required for 12 volt negative ground installations. If the vehicle is a positive ground system be
sure to use the 12 volt positive ground cable, etc.
New vehicles will generally be no problem so far as polarity is concerned. On older
vehicles, the best policy is to use a volt meter and check the battery voltage and polarity before
proceeding with the installation. Experience will generally tell you what the voltage and polarity
of the various make and typ;! vehicles in the field are.
It is extremely important that polarity and voltage be observed because if the polarity is
accidentally reversed, you will, almost without exception, burn out at least one of the power
transistors. TO PREVENT BURNING OUT POWER TRANSISTORS, OBSERVE VOLTAGE AND
POLARITY.
Once the proper cable has been installed in a vehicle, the FM-50-A receiver-transmitter
unit may be exchanged or inter-changed throughout the fleet with no modification or switch
selection required.
COMMUNICATIONS UNIT INSTALLATION
There are generally three or four different ways that the unit may be mounted in the cab
or in area that is accessible to the driver. In most business and industrial applications, it will
be found that it is most desirable to locate the receiver-transmitter somewhere in the cab of
the truck or the front seat area of the vehicle. This has the advantage of short battery cables
with less voltage drop and less chance of abrasion and wear.
Floor Mount: Using the FM-50-A receiver-transmitter as a pattern, place it on the floor of
the vehicle and various locations until the most convenient location is found. The best location
will be one where the driver can tell at a glance whether his set is on or off and where he can
reach the controls on the front panel. When setting up this location, be sure to give considera-
tion to the length of the battery cable. Mter the location is found, secure the universal mount-
ing bracket, Hammarlund Part No. PL26610-Gl. When drilling through the floor of a vehicle,
or through any other panel or part of it, use every precaution to avoid drilling through a gas
line or electrical wiring, etc. Wherever it is not possible to use nuts and bolts, drill with a
proper size drill for self tapping screws and, using a good long screw driver, drive the steel
screws firmly into place. Always fasten parts securely to the vehicle to avoid noise from
"shaky" installation.
Under-Dash Mount: Using the radio as a template, find the best location under the dash of the
vehicle. Take into consideration, special handles found on dump trucks and controls found on
various types of vehicles in the field. Mter a practical location is found, secure the universal
mounting bracket in place with the proper hardware. Use every precaution to make the battery
cable as short as possible and route it in such a way that it will not interfere with the various
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controls under the dash. Wherever the cable goes through the chassis, use a heavy rubber
grommet to prevent chafing and eventual short circuit. Extra precautions seldom take more
time when the installation is being made, but can save many hours of future maintenance and
possibly a dangerous situation for the driver.
Remote Installations: Whenever it is not practical or desirable to have the radio unit mounted
in view of the driver, it should be mounted remotely. In a passenger car the most practical
place is usually in the trunk; however, there are certain vehicles that adapt themselves to other
locations. Always, bear in mind that the battery cable should be as short as possible and use
the same precautions discussed for the floor mount. Place the unit in such a way that it will
not interfere with loading and unloading of the trunk and find the shortest route from the unit
to the battery, running the cable along this route. Avoid sharp metal, protrusions, and use
every means to protect the cable from abrasion. Whenever it is necessary to run the battery
cable on the outside of the vehicle under the floor, stay clear of areas that get extremely hot,
such as the exhaust pipe or the muffler. The cable connecting the unit to the remote head,
should be run on the inside of the vehicle unless it is possible to employ metal flexible tubing.
The remote control unit consists of an "on-off" switch, a volume control, a squelch
control, speaker, and indicator lights. Since it is small and light, it can be mounted almost
anywhere that is convenient to the driver. Wiring and installation instructions are furnished
with the remote control kit.
Battery Cable Installation: The battery cable should be run from the unit to the battery in as
short a line as possible. Somewhere near the battery, mount the fuse holder and fuse with the
two sheet metal screws furnished. Terminate the "hot" lead at the fuse holder, cutting off any
extra cable. Using this extra cable, run a lead from the other side of the fuse holder to the
"hot" side of the battery. Terminate this "hot" lead at the battery terminal, or on the starter
post. Never connect to a voltage point on the vehicle that has wire smaller than the starter
cable. Do not substitute a wire that is of smaller diameter than that furnished with the installa- --
tion kit.
The ground lead (black) must be securely bolted to the ground side of the battery, or to
a good ground point near the battery. Take every precaution against abrasion, and make all
connections tight to prevent future possible maintenance problems.
Antenna Installation: General installation instructions are furnished with the various antenna
kits however there are certain precautions that must be observed when installing any antenna.
The most frequently used antenna will probably be the quarter wave whip. An ideal loca-
tion for this antenna is usually on the roof of the vehicle, or on the deck of the trunk lid. Avoid
mounting the antenna close to, or parallel to, metal objects such as windows, corner posts, etc.
Generally, always mount a quarter wave whip as high as possible on the vehicle and with as
much metal in a flat surface as possible under and around the antenna.
For best possible "car-to-car" communications, the antenna should be mounted at least
18 inches from the edge of the flat portion of the roof and preferably in the center.
1. After drilling a hole of the size called for in the antenna instruction sheet, clean all burrs
above and below the hole. Remove as much of the sound deadening material as possible from
the underside of the roof for a distance of about 1/4 inch around the hole.
2. Run an electricians snake (1/4" wide) through the hole in the roof to the area of the com-
munications unit. It will usually be necessary to pull down one or more cross ribs to provide
clearance for the snake. Use an awl or other small pointed tool to lever the ribs (or pull the
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head lining away from welded in ribs). The small hole in the upholstry may be disguised by
using a whisk broom after removing the tool from the upholstry.
3. Attach the transmission line of the antenna to the end of the snake protruding through the
roof. The recommended procedure for attaching the cable to the snake is as follows.
(a) Drill a small hole in the end of the snake (to clear #18 wire).
(b) Skin the transmission line for approximately one inch, separate the braid and
remove 3/4" of the inner conductor insulation.
(c) Run the inner conductor through the small hole in the end of the snake and twist
together with the braid.
(d) Tape about three inches of this area with thin plastic electrical tape (such as
Scotch Number 33 or equivalent).
NOTE: Before attempting to install the antenna in the vehicle, it is a good idea to try all
pieces for fit to make sure that possible burrs or foreign matter might cause mating
pieces to bind during final assembly.
Routing of Antenna Transmission Line: Always route the transmission line through the area
which provides maximum clearance. AVOID SHARP BENDS. As the cable may go under up-
holstry, metal fittings, etc., be sure to place it in such a way that it will not be squeezed when
the fittings, frames, etc., are put back in place. Mter replacing all trim and metal work, the
co-axial cable and roof top antenna should be checked for continuity between the center conduc-
tor and the whip. The co-axial cable should next be checked for lack of continuity between its
inner and outer conductors.
Attaching Co-Axial Cable Connector:
(a) Cut cable off square at the proper length.
(b) Cut off one and one-eight inches of outside plastic insulation jacket.
(c) Comb out copper shield.
(d) Cut inner insulation off to expose five-eights inches of inner conductor.
(e) Trim stranded shielding so it.is about one-sixteenth inch shorter than the
inner insulation. Slide coupling through and adapter on cable, folding the
combed strands over the adapter.
(f) Tin center conductor and screw plug on cable and adapter.
(g) Solder shield strands through holes in plug and solder center conductor of
the cable to the plug end.
Use enough heat to get a good solder joint. Avoid using so much heat that the solder will
flow the shell to the center conductor inside the plug. Avoid handling the cable and plug until
the softened insulation between the center conductor and shield has had a chance to cool off
and
return to it's firm state.
(h) Recheck for continuity.
NOTE:
The antenna should be cut to it's proper operating frequency. First, determine the
frequency being used then using the chart furnished with the antenna, cut the whip
to the proper length. The steel used in the manufacture of the antenna whip is
usually very tough, and could easily damage diagonal cutters. Therefore, diagonal
pliers should be used only to lightly scar the whip at the correct point, and then
break it by bending back and forth at that point.
Mter the installation is complete, insert a "thru-line" RF watt meter between the FM-50-
A antenna output connector and the PL259 plug of the antenna. Tune the output stage for
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maximum forward power and check reflected power which should normally not exceed 10%.
Unusually
high reflected power may be caused by one of the following reasons:
(a) Incorrect whip length.
(b) Damaged transmission line.
(c) Break in outer shield of transmission line.
(d) Antenna mounted in close proximity to other objects on the vehicle.
In the latter instance (d) modifying the whip length from the "free space"
dimension may correct the condition.
FREQUENCY ADJUSTMENT: The Federal Communications Commission requires that all
transmitters of this type be checked for frequency upon installation and at least once every
twelve months thereafter with an instrument having an accuracy of twice that of the equipment
being measured. In this instance the measuring instrument should be rated at ± .00025%. •
All transmitters are adjusted to frequency prior to shipment however the installer is
required by the FCC to make this test upon completion of the installation.
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OUTERCOM FM-50-A STANDARD MODEL
PARTS LIST AND SCHEMATIC
CI37
CI38
CI40
C141
C142
C143
C144
CI45
CI46
C147
C148
C149
CI50
C151
C152
C153
C154
C155
C156
CI57
CI59
C161
C162
C163
CIM
C167
C168
C169
C170
C172
C173
C174
C176
Cl77
C178
C179
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DESl:RI PTION
PART NO.
dur·mica
dm·15 470 mml ±IO%, 500V. K23006·96
disc. ceramic .02 mfd ±80%-20%, 500V
M23034·27
dur.mica
dm·15 470 mml ±IO%, 500V
K23006.96
dur·mica dm·15 100 mml ±5%, 500V
K23006.72
disc. ceramic .01 mid +80-20%, 600V. M23034·19
mylar .047 mid +20%, 400 V. K23927·1
.005 mid
M23034·31
electrolytic 4 mfd 250V. K23073·78
.005 mid
M23034.31
.005 mid
M23034·31
electrolytic 2 mid 50V. K23073·79
disc. ceramic .01 mid gmv, 1000V M23034·8
10 mimi, dur·mica OM·15, 500V
K23006·22
12 mmf, dur·mica DM.15, 500V K23006·45
12 mml, dur·mica OM.15, 500V K23006·45
Variable Air 2.5 - 32 mml 600V
K34660·G3
Variable Air 3-25 mml 1200V K34453·G8
.0015 mid, gmv
M23034.42
.0015 mid, gmv M23034·42
.0015 mid, gmv M23034·42
Variable, npa,
5-25 mml, 350V
K23038.3
.0015
mid, gmv
M23034·42
disc. ceramic.l mld+80-20%, 100V
M23034·29
temp. compo disc. mpo, Imml ± J4 mml, 1000V
K23010-33
dur·mica OM-15100mmf±5%, 500V K23006·72
disc. ceramic .1 mfd+80-20%, 100V
M23034·29
disc. ceramic.1 mld+80-20%, 100V
M23034·29
dur.mica DM-15 47 mml ±5%, 500V
K23006·71
disc. ceramic .0015 mid gmv, 500V
M23034.42
dur·mica OM-15 100 mml ±5%, 500V
K23006·72
.0015 mid, gmv
M23034.42
disc. ceramic .1 mid ±80-20%, 100V
M23034·29
dur·mica OM-15, 100 mml ±5%, 500V
K23006·72
.005
mid
M23034·31
.005 mid
M23034·31
el ectrol yt ic 40·40·40·/450V, 40/25V K15504·72
SYM80L DESCRIPTION
PART NO
(NOTE: All capacitors are disc ceramic ±20% and 500V unless
otherwise specified)
CIOI
Temp. Comp., Disc. npo, Immf ±J4 mml, 1000V
K23010·33
CI02 .005 mfd
M23034·31
CI03
dur.mi ca dm·15 270 mml ± 5%, 500V K23006·93
Cl04
di sc cerami c .1 mfd + 80 - 20%, 100V
M23034·29
C105
dur.mica dm·15 12 mml ±5%, 500V
K23006·94
Cl06 disc ceramic .002
mid gmv, 1000V
M23034·41
C107
disc ceramic .002 mfd gmv, 1000V
M23034·41
C108
temp. compo disc. npo 2.2 mmf, ±.5%, 1000V
K23010·34
Cl09 temp. camp. disc.
npo, 2.2 mmf, ±.5%, 1000V
K23010·34
CliO Feed thru, special
K23094·1
Cll1
.0015 mid, gmv,
M23034·42
C1I2 .005 mfd
M23034·31
Cll3
.005 mid
M23034·31
Cl14' disc. ceramic .Olmld +80-20%,
600V
M23034·19
C115
dur·mica dm.15 270 mmf ±5%, 500V
K23006·93
C1l6
dur-mico dm·15 270 mml ±5%, 500V
K23006·93
C117 .01 mfd
M23034·28
C1l8 dur·mica
dm·15 100 mml ±5%, 500V
K23006·72
C1l9 disc. ceramic .002
mid gmv, 1000V
K23034·41
CI20 dur·mica
dm·15 47 mmf ±5%, 500V
K23006·71
CI21
temp. compo disc. mpo, 6.8 mml ±.5%, 1000V
K23010·35
CI22 dur·mica
dm·15 22 mml ±5%, 500V
K23006·95
CI23 dur·mico
dm·15 47 mml ±5%, 500V
K23006·71
C125 .005 mid
M23034·31
CI26 .005
mid
M23034·31
C127
dur·mica dm·15 47 mml ±5%, 500V
K23006-71
CI28 disc. ceramic
.01 mfd +80-20%, 600V
M23034·19
CI29 .005
mid
M23034·31
C130
.005 mid
M23034·31
C131
dur·mica dm·15 47 mml ±5%, 500V
M23006·71
CI32 disc. ceramic
.1 mfd
+ 80-20%, 100V
M23034·29
C133 .005 mfd
M23034·31
C134 disc. ceramic .01 mid + 80-20%, 600V
M23034·19
CI35 disc. ceramic .01 mid + 80-20%, 600V
M23034·19
C136
temp. comp. disc npo, 2.2 mml ±5%, 1000V
K23010·34
FREE DOWNLOAD COURTESY OF N9SOR WWW.HAMMARLUND.ORG

SYMBOL
DESCRIPTION
PART NO.
SYMBOL DESCRI PTION
PART NO.
C180 temp. camp. disc.
npo, 4.7 mmf ±.5%,
1000V
K23010-36
CRl12 diode,
(IN 1490)
K41212·1
C181
dur-mica, DM- 15, 24mmf ±.5 mmf, 500V
K23006-48
Hl0l
oven, crystal, 6/12, volt K26638·1
C182 dur-mica, DM-15, 10mmf ±.5 mmf, 500V K23006·22 1101
neon pilot light, amber
K40913·1
C183 variable, npo, 5·25 mmf, 350V K23038·3 1102
neon pi lot Iight, red
K40913.2
C184 dur-mica, DM·15, 270mmf, ±5%, 500V K23006-93
Jl0l
socket, power (24 pin), male
K41136·4
C185 disc. ceramic .002 mfd gmv, 1000V M23034·41
Jl02 connector, receptacle (antenna)
K16111·1
C186
disc. ceramic .002 mfd, gmv, 1000V M23034-41 Jl03
socket (8-pin) (remote)
K16083-1
C187 disc. ceramic .001 mfd, ± 10%, 1000V M23034-22
Jl04
connector (Mi crophone)
K15972-1
C188
disc. ceramic .01 mfd +80-20%, 600V M23034-19 Jl05
socket (II-pin) (test)
K15944-8
C189 dur.mica, DM-15, 470 mmf, ± 10%, 500V
K23006-96 Kl01
relay, 3pdt, 6/12 volt coil
K40351-6
C190 disc. ceramic .01 mfd +80-20%, 600V M23034-19
1101 coil, image trap
K26627-1
C191 dur.mica, DM-15, 120 mmf, ±5%, 500V
K23006.97 Ll02 coil, neutralization K26628·1
C192 dur·mica, DM·19, 1000 mml, ±5%, 300V K23027-9
Ll03 coil, xtal trimming
K26625-1
C193 dur.mica, DM· 19, 1000 mml, ±5%, 300V K23027-9
1104 coil, oscillator leed back
K26621-1
C194 disc. ceramic, .01 mid +80-20%, 600V M23034-19
Ll05 coil, xtal oscillator tuning
K26626-1
C197 electrolytic 200 mid, 25V non-polarized D.C. K23925·1
Ll06 coil, I.F. 10.7 mc
K26623·1
C198 disc. ceramic .0015 mfd gmv 500V
M23034·42
Ll07 coil, I.f,. 10.7
mc
K26624-1
C199
leed thru, special
K23094-1
Ll08
coi I, I.F. 10.7 me
K26622-1
C200 .005 mfd,
M23034.31
Ll09 coi
I. quadrature detector 1650 kc
K26639-1
C201
.005 mid,
M23034·31
L110 inductor, (Input)
K26679-1
C203
.0015 mid, gmv M23034-42
Lll1
inductor, (output)
K26680-1
C204
.0015 mid, gmv
M23034-42
L112 coil, antenna
K26644-1
C205 electrolytic 40 mid 450V K23073-38
1113 coil, plate tank,
K26643-1
C206 disc. ceramic.l mid +80-20%, 100V M23034-29
L114 choke, R.F.
K26640·1
C207
disc. ceramic.1 mfd +80-20%, 100V
M23034-29 Ll15 coil, driver grid
K26632-1
C208
disc. ceramic .01 mfd +80-20%, 600V M23034-19
L116
second mul tipl ier plate
K26631-1
C209
disc. ceramic .002 mId gmv, 1000V M23034·41
L117
first multiplier plate
K26630·1
C210 temp. camp. disc. npo, 27 mml ±5%, 1000V
K23010-39
Lll8
coi I, buffer pi ate
K26629·1
C211 temp. camp. disc. npo, 100 mml ±20%, 1000V K23010-40
L119
choke, rf
K26633-2
CR10l diode, silicon (IN2482) K41211·1
Ll20 choke,
rf
K26633·1
CRl02 diode, silicon
(IN2482)
K41211·1
Ll21 choke, audio, 3
hy
K26667·1
CR103
diode, si Iicon (IN2482) K41211-1
1122
Ii Iter reactor 1.5hy
K26693-1
CR104
diode, (IN 1490) K41212-1
Ll24 choke,
rl
K26640-1
CR105
diode, (IN1490) K41212-1
L125
coi I, driver plote
K26696-1
CR106
diode, (IN 1490)
K41212-1
Ql0l transi star,
2N442
K40764·1
CR107
diode, (IN1490)
K41212-1
Ql02 tronsistor, 2N442
K40764·1
CR108
diode, (IN 1490)
K41212-1
(NOTE:
All resistors fixed ± 10% Y2W. unless otherwise specified)
CR109 diode, (IN1490) K41212-1
Rl01 330K
K19309-109
CRll0
CRIll
diode, (lN1490)
diode,
(IN 1490)
K41212-1
K41212-1
Rl02
Rl03
1.5k
K19309·53
1
meg
K19309·121
-.
-14-
FREE DOWNLOAD COURTESY OF N9SOR WWW.HAMMARLUND.ORG

SYMBOL DESCRIPTION
PART NO.
SYMBOL
DESCRI PTION
PART NO.
Rl04 330 ohms
K19309-37
R146 3301.
K19309-109
R105 331.
K 19309·85 R147 4701.
K19309-113
R106 15k, 1w.
K19310·77 R148
470 ohms, lW
K19310·41
R107
1.51.
K19309·53
R149
1 ohm ±1%
K19443-1
Rl08 331., lW
K19310-85
R150
4.71., lW
K19310-65
Rl09
220 ohms
K 19309-33 R151
8.21., 1W
K19310·71
RllO 470 ohms
K 19309-41
R152
15k
K19309-77
Rill lOOk
K19309-97
R153
20 ohms ±5%
K19309·188
Rll2 lOOk
K 19309·97
R154 lOOk
K19309.97
Rll3 lOOk
K19309·97 R155 lOOk
K 19309-97
Rll4 10k
K19309·73 R1S6 471.
K19309-89
RllS
4701.
K19309·113
R1S8
2201.
K 19309·105
R116 471.
K 19309-89
R159
220 ohms
K19309-33
R1l7 471.
K19309·89
R160 lOOk
K19309-97
RIl8 471.
K 19309·89
R161
2.21.
K 19309·57
Rll9 1 meg.
K19309-121
R162
lOOk
K 19309·97
R120 681.
K 19309-93
R163 lOOk
K19309-97
R121 47k
K19309·89 R164 1501.
K19309·101
R122 4701.
K19309·113
R165 15k
K19309·77
R123 68 ohms
K19309·21
R166
220k
K19309·105
R124 lOOk
K19309-97
R167 3.31.
K19309·61
R125 1.5k
K 19309·53
R168
4701.
K19309-113
R126 1.51.
K 19309-53 R169 470k
K 19309-113
R128
lOOk
K19309·97
R170
1801.
K19309·103
R129 lk, 1W
K 19310·49
R171 lOOk
K19309-97
R130 471.
K19309·89
Rl72 .5
meg
variable ±30% .2W
K15380·7
R131 1.5k
K 19309·53
R173
2.2 meg.
K19309-129
R132 331., 1W
K19310·85
R174
2201.
K19309·105
R133 3301.
K19309-109 R175 3.3k
K 19309·61
R134 3.3 meg.
K19309·133
R176
220k
K19309·10S
R135 vari. 201. ±20%, Y2W
K26218-11
R177
15k,lW
K19310·77
R136 2.2K
K19309·57
R178 1k
K19309·49
R137 3301.
K 19309-109
R179
.47 ohms
M 19302·51
R138 3301.
K19309·109
R180
50, ohms, lOW.
K19430·15
R139 6801.
K 19309·117
R181
500 ohms, lOW.
K 19430-27
R140 8.2 meg.
K19309-143 R183
120 ohms
K19309-27
R141
vari. 5001. ±30%, Y2W
K26218·10 R184
120 ohms
K 19309-27
R142
33k, 1W K 19310-85 R185
1.51.
K 19309-53
R143 lOOk, 2W
K19304·66
R186
470 ohms
K19309-41
R144
lOOk, 1W
K19310·97
R187
10k, 1W.
K19310·73
-15-
FREE DOWNLOAD COURTESY OF N9SOR WWW.HAMMARLUND.ORG

SYMBOL
DESCRIPTION
PART NO.
R188
330k, lW.
K19310·109 Vl05 tube, electron·6BH6 K
16299-1
R189
47k,2W. K19304·58 Vl06 tube, electron·6BH6 K
16299-1
R190
10k
K1930~·73
V107
tube, electron·6BN6
K40908·1
R191
150k
K19309-101
Vl08 tube, electron-12AX7 K16300·1
Rl92
47k
K19309·89 Vl09 tube, electron-6AQ5 K
16387-1
S101
switch, slide (dpdt) (remote local)
K52015-2
Vll0
tube, electran-6146
K40898-2
S102
switch, toggle (dp-3 pos., special)
K26675·1
Vlll tube, el ectron-6360 K40912·1
SP101
speaker, 4x6", 3.2 ohm
M26646-1
V 112
tube, electron-6AW8A K40911-1
Tl01 transformer, antenna
K26620·1
VlI3
tube, el ectron-6BR8 K40907·1
Tl02 transformer, IF, 1650kc
K26648·1
V114
tube, electron-12AX7
K16300-1
Tl03
transformer, IF, 1650kc
K26648·1
Yl01 crystal, receiver channel freq. 10.7 Me
3
M26678-1
Tl04
transformer, IF, 1650kc
K26648·1
Yl02 crystal, transmitter channel freg.
M26678·2
Tl05
transformer, audio output
K26647-1
12
Tl07
transformer, switching
M26672-1
Yl03 crystal 9050kc
K26673·1
Tl08 transformer,
power
P26649-2 Yl03 crystal 12300kc
K26674-1
*see note
VIOl
Vl02
tube,
el ectron·6BS8
tube, electron-6BR8
K40906·1
K40907·1
*Substitute Pt. No. K26674-1 (12300 kc crystal) for Pt. No. K22673·1
(9050kc crystal, "standard") when a harmonic of the 9050 kc crystal
fall s
on the channel freq. ±60kc.
Vl03 tube,
el ectron·6BR8
K40907·1
ZF101 filter, RF, assembly
M26650·1
Vl04 tube,
el ectron·6BR8
K40907-1 ZF102 filter, crystal, 10.7 me K26677.1
MISCELLANEOUS ITEMS
Connector female, 24 terminal (6 and 12 V. cables) K41137-1 Knob, volume and squelch
K26609·1
Connector, female,
24 terminal (117 V. AC cable) M41131·1
Centering washer, cabinet top
K50075-1
Fuseholder, mobile
K51024-1
Terminal, battery K35090·10
Screw, self topping
I18xW' for fuseholder K10081·10 Handle, cabinet K50073·1
Solderless terminal
for mobile cable K35090·9 Coble, power 21110 GA (6 V. cables) KI6543-]
Fuse cartridge,
20 AMP (12 V. mobile) K51025·2 Coble, power 21112 GA (12 V. cables) K16542· 1
Fuse cartridge,
30 AMP (6 V. mobile) K51025-1
-16-
FREE DOWNLOAD COURTESY OF N9SOR WWW.HAMMARLUND.ORG

BASIC OUTERCOM COMPLIMENT CHART
Receiver/Transmitter Unit
Consists of Receiver, Transmitter and Universal
Power Supply in Cabinet with Palm Microphone
and Microphone Mountrlng Hardware
Channel Crystals and Instruction Book
117V
A. C. Power Cord Assembly (Factory Wired)
6
Volt Mobile Power Cable Kit
Consists of Connector, Cable, Fuse Holder
and Fuse, Miscellaneous Hardware and
Assembly fustructions for Positive or
Negative Ground Systems
12 Volt Mobile Power Cable Kit
Consists of Connector, Cable, Fuse Holder
and Fuse, Miscellaneous Hardware and
Assembly fustructions for Positive or
Negative Ground Systems
12 Volt Mobile Power Cable (Factory Wired),
includes Fuse Holder and Fuse and Miscellaneous
Hardware
Universal Mounting Bracket for Mobile
Applications, includes Mounting Hardware
Standard Mobile Antenna Kit
Consists of Antenna Specialists Type
ASP-126 Antenna Assembly with 12'
RG5S/D Cable attached. PL259' Connector and
Cable Adapter supplied but not attached.
Installation Instructions Supplied
High-Gain Mobile Antenna Kit
Consists of Antenna Specialists Type
ASP-177 Antenna Assembly (3 db gain)
with 12' RG58- U Cable attached.
PL259 Connector and Cable Adapter supplied
but not attached. fustallation Instructions
Supplied
Utility
Antenna Kit
Consists of 1/4 Wave Whip with provisions
for direct connection to Antenna Terminal
on rear of FM50-A. Primarily for short
range demonstration of FM50-A on 117V A. C.
operation
Hammarlund
Type or Part Number
FM50-A
PL-26600-G 1
PL-26697-Gl
PL-26698-G1
PL-26698-G2
PL-26698-G3
PL-26610-G1
M-26705-1
M-26706-1
M-26707-1
Revised 3/24/61
-17-
FREE DOWNLOAD COURTESY OF N9SOR WWW.HAMMARLUND.ORG

117VAC.
OPERATION
L..::===----t:=========~J3 AM P.J--~117 V AC.
FUSE
12VDC.
NEGATIVE
GROUND
BLACK
20 AMP.
12 V DC.
+
FUSE RED
@@®®0
12 v. DC.
~~
POSITIVE
8
GROUND
BLACK
7 +
20 AMP.
12 V. DC.
FUSE
RED
®
~~
6 V DC.
NEGATIVE 8
GROUI'JD
00
BLACK
7
30 AMP.
6 V. DC.
+
FUSE RED
6 V
DC.
®~~
POSITIVE 8 5 2
GROUND BLACK
7
00
+
30 AMP.
6 V. DC.
FUSE RED
INPUT PLUG JUMPERS
-18-
FREE DOWNLOAD COURTESY OF N9SOR WWW.HAMMARLUND.ORG

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FREE DOWNLOAD COURTESY OF N9SOR WWW.HAMMARLUND.ORG

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CABINIT, REAR VIEW
-20-
FREE DOWNLOAD COURTESY OF N9SOR WWW.HAMMARLUND.ORG