Hallicrafters HT-46 Operating And Service Instructions

'Bllicraliers

OPERATING

AND

COMMUNICATIONS

SERVICE

TRANSMITTER

MODEL HT-46

INSTRUCTIONS

~ARRA.NTY

"The Hallicrafter's Company warrants each new radio product manu­factured
and agrees to remedy any
change
mal installation, use and service discloses
unit
saler, from whom purchased,
examination, with
days from the date of sale to original purchaser and provided that
such examination discloses in our ;udgment that it is thus defective.

This warranty does not extend
have been sub;ected to misuse, neglect, accident, incorrect wiring not
our own, improper installation,
furnished
altered outside of our factory

nor to accessories used therewith not of our own manufacture.
Any

be remedied
saler without charge to the owner.

This warranty is in lieu of all other warranties expressed or implied
and
other liability in connection with the sale of our radio products:'

by

it to be

free.

from defective material and workmanship

for

any part of any unit of its manufacture which under nor-

is

delivered by the owner to our authorized radio dealer, whole-

by

us, nor extended to units which have been repaired or

where the serial number thereof has been removed, defaced

part of a unit approved

or

exchanged by the authorized radio dealer or whole-

no representative

such defect

all

transportation charges prepaid within ninety

or

or

person

or

to furnish a new part in ex-

such

defect, provided the

or,

authorized service center, intact,

to

any

of

our radio products which

or to use in violation of instructions

authorized service center, nor to cases

for

remedy or exchange hereunder will

is

authorized to assume

for

or changed,

for

us any

Figure

1.

Hol/icrafters'

Model HT-46

Transmitter

.

156-006 958

SECTION

I

GENERAL

DESCRIPTION

1-1. INTRODUCTION.

The

Hallicrafters

Model

HT-46

Transmitter

is a precision

built

compact,

high

performance

transmitter

of

advanced

design.

The

transmitter

utilizes

nine

tubes

and a single

signal

conversion

heterodyning

system

for

transmission

of

single-

sideband

(88B)

and

continuous

wave

(CW)

code

signals

on

the

80, 40,

20,15

and

10

meter

amateur

bands.

The

versatility of the

HT-46

transmitter

permits

operation

as a self-contained

station

transmitter

or may

be

used

in conjunction

with

the

Hallicrafters

Model 8X-146

communications

receiv

er

as a tran

s ce

iver combination.

The

transmitter

is

supplied

with

push-t

o-

talk

control

with

provision

for

the

addition

of the

Hallicrafters

Model

HA-16

for

voice controlled

88B

operation.

Amplified

Auto

matic

Level Contro

l (AALC )

c

ircuitry within the tra

nsmitt

er he

lps preve

nt

"splatter "

due

to se ve

re

"flat-toppin

g" of the

final

amplifi

e r when

unintentionall

y ove

rdri ven.

The

Model

HT-46

may

be

operated

as

a

complete

transmitter

or

as

an

exciter

for

driving

a

linear

amplifier

such

as

the

HT-45,

HT-33B,

HT-41

or

others.

If

others

are

used,

they should

be

capable

of

supplying

a 50

ohm

termination

for

the

Model

HT-46

transmitter.

Other features

of the

Model

HT-46

trans-

mitter

include

:

•

Optional

operation

as

transceiver

with com-

panion

Model

8X-146

receiver

or

as se

lf-

c

ontained

transmitt

er / e

xciter

unit

.

• An

accurately calibrated

VFD

with exce

llent

me

chanic

al

and

temperature

stabilit

y.

•

Constant

tuning rat

e on

all

bands.

• Upper

and

lower

sideband

operati

on on

all

bands

80

throu

gh 10

meters.

• A cr y

stal

latti

ce

filt

er

with 6 poles

for

o

ptimum

sing

le

sideband

r e

sponse.

•

Combinati

on

final

amplifier

plat

e c

urrent

and

RF output

volta

ge

meterin

g for exact

tunin

g.

• 70W to

lOOW

PEP output cover

s exciter r e-

quir

eme

nt

for mo

st 1 KW

linear a

mplifi

er s.

• Keyed

RF car r ier for

CW

oper a

tion

with

s

hapin

g ne two

rk

in keying ci

r c

uit.

- 1

1-2.

TVI
SUPPRESSION.

The
structed
cause

was
layout
selected
arranged
been

that
itself.

television

given

used.

There

cannot

(TELEVISION

HT-46

to

suppress

full

of

the

to

avoid

to

prevent

are,

be

This

is

INTERFERENCE)

has

been

spurious

interference.

consideration

chassis.

prevented
particularly

Components

undesired

parasitic

however,

designed

radiations

in

some

within

true

and

that

The

TVI

problem

the

design

specifically

resonances

oscillations

types

the

transmitter

in

fringe

con-

may

and
and

have

of

TVI

recep-

tion

areas.
low-pass
put

is

recommended.
cussion
special

Amateur's

Radio

problems

Relay

Do not,
attempt
equipment
familiar
within

In

filter

of

measures
Handbook"

League.

this

such

cases,

connected

of

this

IMPORTANT

under

to

operate

before

with

the

manual.

a good

at

the

For a more

that

may

be

type,

refer

published

any

circumstances,

the

Model

becoming

instructions

commercial

transmitter

complete

used

to

to the

by the

American

HT-46

completely

contained

out­dis-

handle

"Radio

Vl 12AT7

V2

V3 6EAB 9

V4

Tuning

Heterodyne

Types

12AT7

6AH6

Ranges

Oscillator

of

Emission

...................

First

and

Second

Amplifier
Carrier

Microphone

MC

Amplifier
Transmitter

.............

Oscillator

IF

Amplifier

Crystals

SECTION

TECHNICAL

TUBES

Microphone

and

Amplifier

and

Mixer

.........

AND

Third

AALC

.

*10M
*10M

*10M
*Heterodyne

* 7.0

*21.0
*28.5

*Supplied with Model

. .

..

II

SPECIFICATIONS

FUNCTIONS

V5
V6

V7
V8

V9

Full

frequency

ranges
80M

40M
20M
15M

10M

mitter.
crystals.)

Type

CR-23/U

Band

28.0

29.0

29.5

SSB -

CW

-

12BY7A

6HF5

6BA6 VFO

6EA8

OA2

coverage

as

follows:

3.5 to 4.0

7.0

to 7.5

14.0 to 14.5

21.0 to 21.5

28.0

to 28.5

28.5 to 29.0
29,0 to 29.5

29.5 to 30.0

oscillator

(Transmitter

in

HC-6

Selectable

Keyed

RF

MC
MC

crystals

Frequency

21,500.000 KC
25,000.000 KC

32,000.000 KC
32,500.000 KC
33,000.000 KC
33,500.000 KC

HT-46.
USB/LSB with
carrier.

Transmitter
Transmitter

fier

Heterodyne
lator

Voltage

of

the

MC

MC
MC
MC
MC
MC

will

accommodate

Holder

and

Mixer

Regulator

Amateur

not

supplied

suppressed

Driver

Power

Crystal

bands

with
full

Ampli-

Oscil-

in

eight

trans­set

carrier.

of

2 -

Frequency

Control

Type of Sideband

Transmission

Dial

Calibration

Calibration

Frequency

Output

Power

Impedance

Input . .

Microphone

Audio

Response

Distortion

Control

Accuracy.

Stability

...

Input

Overall

Products
Unwanted Sideband
Carrier

Power
Station

VOX Unit

SX-146

Transceive

Number

Dimensions

Net

Shipping
Accessories

Suppression

Supply

Control

Input.

of

Weight

Weight

Requirements

Receptacle

. . . . . . . . . . . . . . . . . . . . . .

Cable

Tubes

Overall

. . . . . . . . . . . . . . . . . . . .

.......

Generation

.....

. . . .

. . . .

..

.

.....

.

......

. . . . . . . . . .

Rejection

Capability

Outlet

. . . . . . . . . . . . .

................

Impedance

..........

........

.

..

.

...........

.

....

........

..

.
.
.

Self-contained
SX-146

Solid

receiver.

state

(Nominal
SSB -

CW

- Manual.

5 KC

increments,500

Less

than

indexing
Less

than

minute

warm-up,

VFO

modulator

BW

= 2.1 KC).

Push-to-talk
outlet
cessory.

circuitry.

(Model HA-16.)

Rear
inch two
at

control

one

at

3.5

500

conductor

outlet.

pointer

MC.

cycles

and

or

transceive

with

at

microphone

VOX

key

KC tuning

width

drift

less

operation

9 MC, 6 pole

or

through

control

jack

accepts

phone plug.

is

Key

range.

error

in

first

than

across

hour,

100

cycles

with

crystal

control

optional

standard

circuit

the

dial

after

per

Model

filter

ac-

1/4-

also

after

fifteen

hour

thereafter.
Fixed,

accepts
SSB - 175

CW

0.005V RMS
accepts

500 CPS (Max.) to 2200
26 DB (Min.)
50 DB (Min.)

50

..

117V AC,
Rear

.

Amphenol

contacts,

control,
Rear

.

type
power

Rear

(Supplied.)
operation

75

8

5-7/8 x 13-1/8

26

28 pounds

VOX
attachment
voice

Model
three
pound. Shipping

50

ohms.

RCA type phono plug. (Supplied.)

Watts

- 150

Watts

into

standard

below

below

DB (Min.)

below

50/60

chassis

type

speaker

etc.

chaSSis

71-6S

and

chassis

mounted

plug. (Supplied with

control

receptacle

Provides

with Model SX-146.

ohms.

Use

Amphenol

plus 1 voltage

pounds.

(Approximately)

Control

to

controlled

HT-46

tubes

through

and

Rear

PEP

Maximum

Maximum

high

impedance

1/4-inch

CPS

PEP

PEP

output

PEP
cycles,
mounted

86-PM11

muting,

six-pin

for

VOX

inter-connection

regulator

x 11

inches

Unit

Model HA-16.

rear

of

Model

operation.

single
sensitive
Weight-1-l/2

chassis

mounted

load.

three

conductor

(Min.)

at

6 DB.

reference.

at

800 to 2200 CPS input.

output.

350

Watts.

eleven-pin

plug. (Supplied.)

receiver

socket

muting,

accepts

jumper

Adaptor,

accepts

cable

and

NO.

Model HA-16.

RCA

21-597

15

diodes.

(HWD).

Designed

HT-46

(VOX)

plug-in

VOX

Power

connector.

relay.

cabinet

Net

pounds

receptacle

Panel

connector

phone plug.

socket

accepts

Provides

relay

transmitter

Amphenol

wire.)

type

Provides

phono plug.

for

transceive

or

equivalent.

for

to

is

derived

quick

provide

from

Contains

Weight -3/4

(approximately).

Fuse

. . . . . . . . . . . . . . . . . . . . . . . . . .

.. 3 amperes,

slow

blow, 3

AG

type.

- 3

SECTION

III

INSTALLATION

WARNING

LETHAL

HIGH

VOLTA

GE

IS

PRESENT

WITHIN

THIS

EQUIPMENT.

BE

CARE-

FUL

WHEN

INSTALLING THE

UNIT

OR

PERFORMING

CHECKS

OR

ADJUS T-

MENTS

INSIDE

THE

CABINET.

3-1.

UNPACKING

.

Ca

refully remove

the

equipment

from it

s

carton and

packing material

and

examine

it

for

possible dama

ge

which may

have occurred

in

transit

. Should any sign

of dama

ge

be

apparent

,

immediately

fil

e a

claim

with the c

arrier sta

tin

g

the extent

of the

damage.

Che

ck

all

shipping lab

els

and

tags

for

special

instructions be

for e r emoving

or

destroying

them.

3-

2.

LO

CATION.

The transmitt

er

may be

installed

in any

l

ocati

on

that

will

permit

free

circulation

of

air

thr

ough

the

ventilation

openin

gs

in

the

cab

ine

t.

Do

not

place

any

obj

ect

on

top

of

the

cabinet

in

o

S

X-146

INJEC

T

J3

t t

•

GROUND

AN1ENNA

J4

J5

a

manner

that

will

obs

tru

ct

normal

ventilation

.

Avoid

exce

ssiv

ely

warm locations

such

as thos

e

near

radiators

and

heating vents.

3

-3.

PO

WER

SOURCE

.

Th

e Mo

del

HT-46

Transmitter

is design

ed

to

operate

from

a 105/ 125V 50/ 60 cycle

AC

pow

er

Sour

ce.

Nominal line voltage

for

testing

and mea-

surements

is

117V

.

The outlet

should

be

capabl

e

of

handlin

g a 350 w

att load

with

good reg

ulati

on.

IMPORTAN

T

If

in

doubt

about

your

power sour

ce,

co

nta

ct your loc

al

pow

er

company

prior

to

inserting the

power

cord into an

y

po

wer outl

et.

Plugging the power

co r d

into the wr

ong

source

of

power can

cause exte

nsive dama

ge

to the

trans-

mitter.

Set the

OPERATION c

ontr

ol

at OFF (fUll

co

unt

er clockwis

e)

and

make

all

installation

con

-

nection

s b

efo

r e connecting the transmitter

to a

source

of

power

.

•

PI, J6

R33

MODEL

HT-46

105/125

VOLTS

50160

CPS

@\

POWER

CONSUIolPTION

350

WATTS

,

_'!/J

BIA

S

KEY

f

AMP

ADJ

J2

FI

156-0070

28

Figure

2.

Rear

View

of

Transmitter

.

4 -

SPKR

I

,~

HUH

,~

SX

GND

,~

I

146

GND

EXTOSC@

INPUT

.8

SLAVE

6~\~~~

®

ANT

®<

AHPHENDL

lY

PE

21-591

lh

TRANSCEIVE

CABLE

1-"

HT-46

,----5

q

SX-4~

®

ii

ANTENN

'\.7

L------J-------+-------+----t----

L-------+-------+---------t

3-4.

ANTENNA_

The

Model

terminate

into a
line. A non-reactive
results,
modated
results.
antennas
give

however

by

Any of

using

excellent

For
antennas,
book"
by

the

refer

or

the"

American

Some
be

provided

code

The

ANTENNA
chassis
nector.
for

feed

apron

Use

line
changeover
details.

3-5.

GROUNDS.

All

station
gether

with

connected

ground.
provided
for

this

An

on

purpose.

HT-46
50

a VSWR

the

50

results.

further

to

ARRL

Radio

form

of

requirements.

mates

RG-58/U

to a linear

relay,

heavy

to a cold

external

the

Model

EARIH
WATER
GROUND

Figure

Transmitter

ohm

unbalanced

load

is

of

transmitter

the

popular

g,q.~

transmission

information

the

"Radio

Antenna

Relay

IMPORTANT

lightning

which

will

connector

with

an

co-axial

Refer

to

eqUipment

copper

water

chassis

HT

-46

OR

COLD

PIPE

RG58/U-50~

3.

Typical

Interconnections

is

designed

transmission

preferred

2.5/1

for

can

with

di-pole

optimum

be

accom-

acceptable

or

lines

on

the

subject

Amateur's

Book" ,

both

Hand-

published

League.

protection

comply

located

RCA-type

cable

amplifier

should

with

local

on
phono

or

equivalent

or

the

antenna

Figures 2 and 3 for

should

wire

pipe

or

or

ground

rear

chassis

be

bonded

braid

outside

terminal

apron

to

beam

will

of

rear
con-

to-

and

earth

is

I

i

----1I--.:;;;-;:--

CALIBRATE

SIGNAL

PICKUP

LEAD

WHEN

REQUIRED

for Model

STANDARD
1/4-INCH

Figure

STANDARD
1/4-INCH

Figure

3-6.

front
with a standard
plug
high
phone

usually

especially

~

~ ~ ~ ~ ~ ~ m ~ ~

I, t UJ6

E

Xl

SPEAKER

1-"

HT-46

32

~

RG58/U-5DA

and

Model

2-,lJ

I 5 1

III

VAC

ANTENNA

SX·146.

COAXiAl

b

TIP

RING

:3

PHONE

4. Microphone Wiring for

0

c5

TIP

RING SLEEVE

PHONE

5.

Microphone

MICROPHONE.

The

microphone

panel.

wired

as

impedance

may

be

for

SLEEVE

CONDUCTOR

PLUG

:3

CONDUCTOR

PLUG

Control

The

microphone

1/4-inch,

shown

crystal

be

used,

achieved

voice

Wiring for

Unit

in

with a microphone

communications

3

LLk.~~J:l~~H

KEY

CONNECTION

(J:

DR

RS58tU

--

III

VAC

156-007044

-,

I

Bf

RElAY

d:

A

RS8tU

~-"'I"":;';:';;';";;;;";~---

RT

1-"

1-

1°

--

I

I

~C~O~

Push-

To-

Talk

Transmitter

--

--

I
I

I

I

I

l.!:!!C~~

Transmitter

Model

receptacle

three

Figures 4 and

or

dynamic

however

HA-16.

cable

conductor

best

Control

is

located

should

results

--

~

5. Any good

type

use.

I

':'

-l

156-007026

Control.

I

I

G

I

-

-1

156·007027

with

VOX

on

the

be

fitted

phone

micro-

will

designed

- 5

The

microphone

may

also

be
microphones
mute

the

microphone
pressed,
Ie

ss

3-7.

hence

the

microphone

KEY.

The

station
transmitter
rear

chassis
Refer
two
so
which
TROL
with
tion

to

Figure

conductor

that

the

is

at

OUTLET

Pins

NO.1

to

the

keyer.

used

fitted

VOX

at

the

apron

3. The

1/4-inch

key

base

ground

maybe

or

circuit

with

VOX

with

push-to-talk

element

operation

switch

keyer

may

closed

or

at

the

key

phone plug.

connects

potential.

used

NO. 8 used

shown

control,

in

Figure

however

switches

until

the

switch

is

not

possible

is

altered

be

circuit

accordingly.

connected

key

jack

CONTROL OUTLET.

jack

accepts a standard

Wire

the

to

the

plug

sleeve

Pin

NO.

90f

the CON-

to

key

the

transmitter

for

ground

connec-

some

also

un-

to

the

at

the

plug

is

4

Receiver

Keying

PTT

SPDT

Calibrate

3-10.

FUSE.

Specifications: 3 amperes,

muting:

circuit:

control

relay

signal

Pins

Pins

circuit:

contacts:

coupling:

NO.6

NO.9

Pins

Pins

AND

and

NO.

NO.3,

NO.

Pin

slow

and

NO.8

NO.8

10

and

5

NO. 11

blOW, 3 AG

NO.

NO.4

8

type.

3-11.

ACCESSORY

INSTALLATION.

When

the

the

keyer

tune

circuit

up

in

the CW-TUNE

TION contro1.

When the
OUTLET,
jack

3-8.

insert a dummy

to

hold

the

SX-146

INJECT.

Transceive
able

when a
between
Model SX-146

The
INJECT
SLAVE
removing
receiver
venient
should

75-ohm

the

Model

receiver.

cable

receptacle

OUTPUT

the

receptacle.

length to

be

made up
RCA-type phono
75-ohm
(NO. 21-597)
microphone

3-9.

be

station

that

control

co-axial

CONTROL

The

required

wiring

the

following

outlet.

is

type

control

by the

Speaker

keyer

is

plugged into the KEY

must

be

position

keyer

is

wired

phone plug into the

circuit

type of

open

operation

co-axial

HT-46

is

connected

on

the

connector

82

ohm

dummy

The

cable
reach
of

plugs

cable

between

75-ohm

at

each

made

recommended.

cable

for

this

OUTLET.

outlet

circuitry

station

circuit

is

shown

facilities

muting:

Pins

NO.7 & NO.1.

jack

closed

into

for

of

the

SSB

the

or

CW

OPERA-

CONTROL

key

for

CW

operation.

is

made

avail-

cable

is

connected

transmitter

between

transmitter

on the

receiver
load
may

co-axial
end.

Small

by

Amphenol

Do

not

and

the SX-146

and

plug

be

any

the

units

cable

diameter

use

shielded

the

after

in

con-

and

with

Corp

the

the

application.

mayor

may

not

installation. A typical

in

Figure

are

available

NO.2 & NO.8

3. Note
at

the

and

1. 10
tional
coverage.
sary
(Refer
indicate

crystals

To

to

remove

to

paragraph

their

BAND

28.0

29.0

29.5

2.

VOX

Model HA-16

voice

control
mitter.
mitter

It

is

cabinet

A.
sently
on
Save
the

installed

the

rear

the

control

jumper

unit

B.

of

the

transmitter

about

1/8

inch

C. Hook

unit

into the two

wall

just

above the

notched

ground

flange between the

bolt.

D.

the

control

unit

is

now

ready

Meter
install

location.

Band

will

be

the

the top

7-2).

FREQUENCY
32,000.000

33,000.000

Crystals:

required

crystals

portion

Chassis

The

crystals

for

full

it

will

of the

markings

required

KC

KC

Three

10

be

NUMBER

019-201963

019-201965

33,500.000 KC 019-201966

Control Unit Model HA-16: The

adapter

operation

installed

as

Remove the

chassis

Loosen

unit

of

the

on the

follows:

in the

VOX

apron

plug

for

is

disconnected.

the

and

space

is

available

Model

rear

jumper

UNIT

of

it

must

ground

HT-46

of the

plug
socket

the

transmitter.

be

bolt

the

flat

to

(PI)

replaced

at

apart.

the

Tighten

Plug

unit

into the

for

Model HA-16

key

holes

ground

the

ground

the

inter-connecting

VOX

adjustment

in

bolt

flat

the

and

washers

bolt

UNIT

and

VOX

rear

insert

nut.

socket.

operation.

addi-

meter

neces-

cabinet

will

are:

PART

provide

Trans-

trans-

pre-

located

the

rear

washers

control
cabinet

the

of

the

cable

The

if

of

6 -

SECTION

IV

4-1.

TUN

ING

The
quency
of
a

of

the

transmission

separate
operating
the

Model SX-146

this

control

mission

is

Note

to

right

for

the

calibration
logged
from

below

right

The

lowest

frequency

tuned.

4-2.

OPERATION

The OPERATION

switch

as

which

follows:

POSITION
OFF

STBY

USB/LSB

(Two

CW-TUNE

CONTROL.

tuning

control

VFO to

when the

unit.

(VFO

the

transmitter

receiver

is

disabled

controlled

that

the

two

bands

marks.

these

marks,

to

left.

BAND

SELECTOR

of

CONTROL.

controls

positions)

FUNCTIONS

is

select

transmitter

switch

as a transceiver

(VFO

and

the

by

the

frequency

whose

numbers

For

the

the

band

control

the

mode

Removes
from

Application

power

and

plate
tubes
in a stand-by
transmitter

permits

cuits
time.

In

these
transmitter
operation

band

mode
color
or

LSB

and

is
SELECTOR
ings.

This

transmitter

carrier
ing

the

operation.

position,

may

also

operation.

used

to

vary

the

desired

at

XMTR.) When

switchatRCVR)

frequency

receiver.

increases

the

remaining

frequency

setting

or

band

segment

is a six

of

transmission

FUNCTION

all

primary

the

transmitter.

places

voltages

which

are
condition. The
control

the

receiver

to

function

two pOSitions

is

for

suppressed

of

transmission.

code

indicates

for

the

so

coded

panel

position

on

only

to

transmitter

In

the
be

keyed

OF

the

frequency

is

used

of

trans-

from

appear

indicates

of

single

above
bands

increases

being

position

power

primary

both

heater
on the

biased

relay

at

placed

side-

carrier

band

in

on

the

BAND

mark-

places

the

air

permit

for

this

same

transmitter

for

OPERATING

fre-

as

with

left

the

off

cir-

this

the

in

The

USB

use

the
with
tun-

SSB

CW

4-3.

balanced
audio

range
level
tions.

4-4.

tuned
driver

The

mitter
as a transceiver

4-5.

output
transmitter
tion.

switch
level.

4-6.

rotary

crystals

shown

refer
band

4-7.

capacitor

the

calibrated

the
procedure.

4-8.

metered

idle

trol,

current

voltage

the

CONTROLS

STBY

MIC

GAIN.

This

control

modulator

amplifier

to

handle

microphone

DRIVER

The

circuits

control

CARRIER

The

The

is

BAND

The

switch

on
to the

pOSitions on

FINAL

The

P A

capacitor

METER

The

1.

plate

and

2. At RFO,

output

TUNE.

DRIVER TUNE

stages

is

output when

CARRIER

level

for

tuning

control

set

at

SELECTOR.

BAND

which
required
the

dial.

TUNE.

FINAL TUNE

that

stage

in

band

SWITCH.

METER

circuits

At

MA

current

to

indicate

on

the

across

of

the

This
position
heater
and

ceiver

sets

stage

stages.

any

high

deSigned

of

the

signal

driving

always

tuned

operating

with

the

LEVEL.

LEVEL

CW

process

also

ON to

control

SELECTOR

selects

to tune

The

color

USB/LSB

the

OPERATION

tunes

the

to

the

antenna

segments

near

resonance

switch

in

the

the

meter

when

final

40 to 300

the

the

50

transmitter.

is a second

which

and

again

circuits

the

audio

from

The

control

impedance

for

voice

control

frequency

the

final

for

as a transmitter

SX-146

control

operation

for

CW

functions

the

is

the

tuned

the

frequency

coded

coding

control

pi-network

load.

to

permit
during

selects

transmitter.

is

setting

the BIAS ADJ.

amplifier

milliampere

meter

ohm

indicates

transmission

The

stand-by

retains

supply

permits

the

voltages

the

re-

to function.

level

to the

the

microphone

has

sufficient

high

or

low

communica-

resonates

mixer

amplifier

maximum

the

and

stage.

trans-

or

receiver.

sets

the

RF

and

during

or

SSB

when

calibrate

an

eight

circuits

the

opera-

the

CAL

signal

position

and

ranges

panel

markings

for

the

two

side

control.

drives a variable

used

to couple

The

control
presetting
the

tuning

either

used

to

of

read

two

the

con-

stage

plate

range.

the

RF

line

scale

is

cali-

is

at

- 7