Table 1-3.-UHF-1 and UHF-2 Operating Modes
guard receiver is a separate module and is a complete
and independent fixed-tuned, crystal-controlled
receiver that operates on the guard frequencies. The
receiver sections receive command signals from the
control box, placing it in the proper condition for the
mode selected. All receiver outputs derived from guard,
FM, FSK, wide-band, and voice modes are routed
through the audio interface, and then switched through
the COMM switching matrix to the external equipment.
UHF-2 Receive
The RF signal received at the UHF tailcap or UHF
lower antenna is coupled into the UHF-2 RT through the
antenna switching relay, and the UHF filter. From this
point on, the operation is the same as in the UHF-1 radio
set.
Modes of Operation
Table 1-3 shows the modes of operation for the two
radio sets.
HF COMMUNICATIONS
Learning Objective:
Recognize components
and operating principles of the HF radio
system.
The AN/ARC-161 HF radio system provides
two-way communications between the aircraft and any
similarly equipped platform. It provides transmission,
reception, and processing of intelligence and tactical
data. The cipher voice communication is provided by
the TSEC/KY-75 high-frequency security unit.
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