Hammarlund FM50A Manual

I

1

,

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"

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

-

--

---

--

-----

-

--

-=-

--

---

;-i~j~~;

••••

~

•••••

;;~~::::~:!I!.IIi

••

~;::Z~;;;a,

--

-...!

--

:--

--

---

--

---

--

---

.......

--

---

--

-=--

--

-=--

-:......

--

-:......

--

---

--=--

---

--=--

---

=-

--

-=--

--

---

--=--

--.

--=--

---

--:.....

---

--

-

---

--

--.

--

---

--

---

--- ---

-:......

--

---

--...

--.

---

--

---

=--

---

--

-=--

---

--

--=--

--

--.

--

-----=--

-

--

-=--

--

---

--

--=--

--

---

--- ---

--:.....

--

=-=-

--

---

--

---

--:......

--

---

----

--:.....

---

-------

--

-=--

--

--:......

---

--

--=--

---

--=--

---

------

---

~

--

------

---

--=--

----

---

--

------=--

:--

------

---

--

----

---

--

--=--

--

--=--

---..

----

---

--

--::-

---

FRONT

VIEW

MODEL

FM-50-A

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

I

-

--

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:

I~

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

1_---

I

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

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.

-4-

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

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,

-5-

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

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)

-6-

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

(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

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

9

of

V104A.

(b)

Connect

micro-ammeter

from

J105

3

to

ground.

(position

3

of

recommended

test

meter)

(c)

Adjust

top

and

bottom

of T104

for

maximum

indication.

-7-

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

2. (a)

Connect

micro-ammeter

from

J105

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

1

of

V102A.

(b)

Leave

micro-ammeter

connected

to

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

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

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).

-8-

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

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

-9-

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

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

-10-

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG

Hammarlund FM50A Manual

Manuales populares de Transceptor de otras marcas