Hammarlund HX-50 - Function of Operating Controls; Control Descriptions

45 pages

Save Page as PDF

To Next Page

To Next Page

To Previous Page

To Previous Page

Loading...

m

FUNCTION

OF

OPERATING

CONTROLS

FUNCTION

SWITCH

The

Function

Switch

determines

the

type

of

emitted

signal

selected

by

the

station

operator.

The

HX-500

is

capable

of

transmitting

the

following

types

of

signals

as

indicated

on

the

knob:

LSB,

USB,

DSB (AM),

CW,

FSK,

and

FM.

OPERATION

SWITCH

The

five

position

Operations

Switch

turns

the

AC

power

ON

(Standby)

and

OFF,

and

inel

udes

the

MOX,

VOX,

and

Calibrate

positions.

When

manual

control

of

the

transmitter

is

desired,

the

MOX

position

is

used.

In

the

MOX

position,

the

antenna

and

VOX

relays

are

always

energized

and

are

completely

independent

of

control

by

the

VOX

circuit

knobs

(VOX

sensitivity,

VOX

delay

and

anti-trip).

In

the

VOX

position,

the

transmitted

output

is

controlled

by

the

voice

energy

from

the

microphone.

In

this

position,

the

antenna

and

VOX

Relays

are

controlled

by

the

adjustment

of

the

VOX

circuit

controls.

The

proper

setting

of

the

VOX

knobs

is

outlined

in

the

Tuning

Procedure.

In

the

calibrate

position,

the

Antenna

and

VOX

Relays

are

always

in

the

de-energized

position

(receive).

This

position

is

used

to monitor

the

trans-

mitted

signal

in

the

communications

receiver

and

is

also

used

for

zero

beating

the

HX-500

signal

fre-

quency

to

an

incoming

signal

or

desired

frequency.

CALI

BRATE

LEVEL

A

calibrate

level

control

is

included

in

the

trans-

mitter

to

adjust

the

amount

of

signal

fed

into

the

receiver

from

the

transmitter

in

the

Cal

position.

The

Calibrate

Level

knob

is

adjusted

so

that

the

desired

level

of

the

transmitter

output

as

observed

on

"s"

meter

of

Receiver

or

the

loudspeaker,

(or

headset

connected

to

Monitor

Jack)

is

sufficient

for

monitoring.

A

very

limited

amount

of

RF

power

is

"leaked"

from

the

final

amplifier

tank

circuit

to

the

receiver

input

via

the

Antenna

Relay

wiring.

R.F.

LEVEL

The

RF

Level

control

adjusts

the

gain

of

the

5.55

to

6.05

Mcs

broadband

amplifier.

Optimum

RF

output

on

all

bands

is

achieved

with

the

adjustment

of

this

control.

This

is

usually

set

at

4

to

5.

Page

6

AUDIO

LEVEL

The

audio

level

control

adjusts

the

amount

of

audio

gain

required

to

fully

voice

modulate

the

transmitter.

This

is

usually

set

at

5.

DRIVER TUNE

The

Driver

Tune

knob

adjusts

both

the

3rd

mixer

plate

and

driver

plate

tuned

circuits

to

resonance

at

the

frequency

desired.

FINAL

TUNE ,

The

Final

Tune

knob

adjusts

the

output

tank

capacitor

for maximum

RF

output.

The

knob

skirt

is

marked

to

indicate

the

designated

area

on

each

band

w

here

maximum

output

can

be

obtained

as

observed

on

RF

Level

indicator.

BAND

SELECTOR

The

eight

position

Band

Selector

control

selects

the

proper

combination

of

tuned

circuits

and

the

proper

heterodyne

crystal

on

each

band.

The

Band

Selector

shaft

also

indexes

the

direct

reading

dial

drum

which

indicates

the

band

in

use.

METER

SENSITIVITY

The

meter

sensitivity

knob

controls

the

amount of

deflection

of

the

output

level

meter.

Clockwise

rotation

increases

the

sensitivity

of

the

meter

circuit.

The

Output

Level

Meter

is

used

to

tune

up

the

transmitter

to

any

frequency

within

its

range.

The

meter

indication

is

logarithmically

proportional

to

the

RF

voltage

across

the

50

Ohm

output.

This

fea-

ture

gives

the

meter

wider

dynamic

range

of

indi-

cation.

DIAL

DRAG

& LOCK

The

small

knob

adjacent

to

the

Frequency

tuning

knob

has

been

included

in

the

HX-500 for

the

pur-

pose

locking

the

dial

drive

to

a

selected

frequency

and

adjusting

the

tuning

knob

calibration.

Clockwise

rotation

of

this

knob

restrains

the

frequency

knob

from

turning.

It

also

enables

the

adjustment

of

dial

action

or

torque

required

for

personal

preference

of

the

operator.

FREE DOWNLOAD

COURTESY OF N9SOR

WWW.HAMMARLUND.ORG