Command Post Radio Operation

TM 11-5821-285-12-1

interphone selector switch to PVT on the private

indicated by

intercom.

the

(b) Set the desired applicable ICS box RECEIVERS

presence of

short

INT switch down to converse on the private intercom

beep in the

without listening to the normal intercom.

headset. If

such a tone

(1)(d) above.

heard,

b. Command Post Radio Operation. The radios can

the cipher

be operated from any console position. Any FM radio

equipment

can be operated in an unciphered or ciphered mode

must

depending upon installed equipment.

adjusted for

CAUTION

receipt of a

PLAIN/CIP

ciphered

HER

message as

indicator

in (2) below.

lamps will

(2) Cipher mode operation

light with or

(a) Set the PLAIN/CIPHER switch on the KY-28

without

control head to the CIPHER position. The CIPHER

cipher

indicator lamp (green) should light.

equipment

(b) For only the KY-28 control head and its

installed.

associated cipher equipment, set the RE-XIREG switch

Check that

to REG. A constant tone of 1, 200 Hz should be heard

TSEC

for approximately two seconds. After two

equipment

is installed

and

connected

prior

cipher

mode

operation.

(1) Plain mode operation (unciphered).

(a) Set the PLAIN/CIPHER switch on the KY-28

control head to the PLAIN position. The PLAIN indicator

lamp (red) should light.

(b) Set the applicable ICS box transmit- interphone

selector switch that is associated with your headset as

follows:

For UHF communications, set switch to 4.

For FM-1 radio communications, set

switch to 1.

For FM-2 radio communications, set

switch to 2.

For FM-3 radio communications, set

switch to 3.

CAUTION

Ensure that

antennas

are

connected

before

transmitting

U-94A/U and speak into the microphone to transmit.

Release the switch to listen.

NOTE

Receipt of a

ciphered

message

will