TABLE 2-1. RECEIVER/EXCITER CONTROLS AND INDICATORS

TM 11-5820-919-12

TABLE 2-1. RECEIVER/EXCITER CONTROLS AND INDICATORS

NOTE

Prefix reference designators with Al

Reference

Control/Indicator

Designator

Function

AUDIO connector

A4A2J1,

Interface connection with input/output devices

A4A2J2

FREQUENCY-KHZ switch

A4S1-A4S6

Selects 1 of 280,000 discrete frequencies between 2-

and 29.9999-MHz

SB switch

A4S7

Selects either USB (upper sideband) or LSB (lower

sideband) operation

MODE switch

A4S8

Selects four modes of operation:

V-RCV - Voice and cw receive only

V-TR - Voice and cw transmit and receive

D-TR - Data transmit and receive

D-RCV - Data receive only

VOLUME OFF/MAX

A4S9/R1

Turns power on or off and adjusts the audio level;

switch control

OFF removes power; MAX indicates maximum audio

level

LIGHT switch

A4S10

Illuminates FREQUENCY-KHZ readouts (with red

light) when pressed

Connector

Interface connection with amplifier/coupler

increase, the antenna is open, shorted or otherwise

free of obstructions, adjust the antenna length, clear the

faulty.

tune fault and attempt a retune. If all efforts to tune fail,

the antenna tuner is defective. If a spare

2-13.

NO-TUNE INDICATOR.

If the tuning tone

amplifier/coupler assembly is not available and

continues for a very long time (8 thru 12 seconds) and a

communication is essential, refer to paragraph 2-15 on

beeping sound is heard after the tuning tone stops the

use of the bypass mode.

tuner has failed to tune and a tune-fault has occurred.

(The beeping tune-fault tone will also be heard if the

2-14.

VSWR INDICATOR.

If the antenna or its

operator selects a frequency below 2 MHz). Turn the

radio off and then back on and momentarily press the

immediate environment is disturbed during a

PTT switch to start a second attempt at tuning. If a

transmission, its impedance will change and a high vswr

second tune fault occurs, the antenna is open or shorted

(unmatched) condition will occur. The antenna tuner will

or possibly not suitable for the frequency in use. If all

measure the vswr at the beginning of the next

connections to the antenna are tight, no shorts are

transmission and will retune if the impedance change is

evident, and the antenna is

permanent.

A short beep at the beginning of a

transmission indicates a previous momentary high

2-3