General Operating Features

1-15. General Operating Features

The receiver/transmitter used in models AN/URC-100, AN/URC-101 and AN/UBC-104 is a solid-state voice line-of-sight

radio set normally used to receive and transmit plain text voice messages. They can also be used with external

COMSEC equipment to transmit and receive cipher text (encrypted or scrambled) messages. The AN/URC-100 and

AN/URC-101 operate in the 116 to 150 MHz VHF band and in the 225 to 400 MHz UHF band The AN/URC-104 radio

operates in the 30 to 88 MHz VHF band and in the 225 to 400 MHz UHF band. The three models are tunable across their

frequency ranges in 25 kHz steps.

Operating power for the receiver/transmitter comes from the battery pack that supplies -28 V to operate the radio circuits

and the front panel lamps. The display operates from +5 V which is stepped down from the +28V.

The receiver/transmitter should be operated at a 9:1 receive to transmit duty cycle. When operating at this ratio, the

batteries will last 8 hours for low power (5 watts) output and 6 hours for high power (20 watts) output. Operating in the

beacon mode the batteries will last 1.5 hours with low power (5 watt) output.

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