ELECTRICAL AND SIGNAL CHARACTERISTICS

TM 11-5895-1141-34

operator's microphone is amplified and processed by this assembly. The assembly output is sent to the selected radio

channel selector module and to the recorder-monitor module. A brightness control for all the indicator lamps, as well as

the ac power fuse, are located on the front panel of this assembly.

b. Recorder-Monitor Module. This module is used to couple the transmitted audio originating at the operator's

microphone and the received audio from the radio receiver to a recorder (not furnished). An indicator lamp mounted on

the front panel of the module flashes when audio is being recorded.

c. Volume Control Module. Received audio is amplified by this module whose output is then delivered to either the

loudspeaker or the operator's headset. Two volume controls are mounted on the front panel of this module, one for the

loudspeaker audio and the other for the headset.

d. Radio Channel Selector Module. The keying and interlocking functions are performed by this module. When the

operator depresses his push-to-talk switch, and the lock/nonlock switch (located on the front panel of the module) is

closed, the transmitter is then keyed, provided the channel is not already engaged by another operator. In the event the

channel is already engaged, the interlock circuits prevent keying the channel transmitter from this position and an audible

tone is generated to notify the operator. Note there is provision for up to 8 selector modules to control up to 8 radio

channels located on the selector unit. A three section lamp display on this module indicates (1) when the operator has

keyed the transmitter from this location (red lamp), (2) when the locking-lock switch is on (green lamp), (3) when the audio

is being received from the channel's receiver output (amber lamp).

e. Headset/Microphone Jack Panel Assembly.

Receptacles are mounted on this panel for mating with the

microphone or headset being used by the operator.

1-7. ELECTRICAL AND SIGNAL CHARACTERISTICS

The C-10931(P)/FRC electrical and signal characteristics are listed in TM 11-5895-1141-12.

1-8. OPERATION

A general description and operating instructions for the C-10931(P)/FRC is given in TM 11-5895-1141-12.

1-9. DIFFERENCES BETWEEN MODELS

There is only one model of the C-10931(P)/FRC.

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