When not in the AJ mode, it operates as a tone
transmission switch only.
Standby Operation. Normal operation
using the aircraft survivability equipment/ avionics
control system (ASE/ACS) is described in chapter 4.
Turn on procedure:
(overhead control panel, fig. 2-15) - ON.
UHF transceiver 164
switch (pedestal extension, fig. 2-14) -
Function select switch - MAIN BOTH
position, as required.
If function selector is at MAIN setting,
communications will be received. If
emergency communications on the
Transceiver operating procedure.
(audio control panel, fig. 3-1) - 3.
Microphone switch - Depress to transmit.
Preset channel selection.
Function selector switch - MAIN.
Mode selector switch - PRE.
Manual frequency selector switches - Set
frequency to be placed into memory.
Preset channel selector switch - Set
desired channel number.
SET switch - Depress.
(COMPLETE PROVISIONS ONLY).
Complete provisions only are provided for a TSEC/ KY-
58 voice security system. This system provides secure
(ciphered) two-way voice communications for the pilot
and copilot in conjunction with the # 1 UHF, VHF-FM
(SINC-GARS), and # 2 (BU VOW) transceivers. The
be located in the left equipment rack behind the pilot.
System circuits are protected by the UHF, VHF-FM, and
BU VOW circuit breakers on the overhead circuit breaker
panel (fig. 2-9).
3-9. BACK-UP VOICE ORDER WIRE (BU VOW)
A transceiver identical in type and performance to the
UHF transceiver (fig. 3-3) is located on the left
equipment rack, to serve as a back-up voice order wire.
The transceiver can only be controlled by the ASE/ACS.
Standby control is not available. The transceiver is
selected on the audio control panel (fig. 3-1) by
transmitter-intercom selector switch position number 5
and by radio audio monitor control number 5. This set
provides for secure communications through interfacing
with a voice security system. The back-up voice order
wire set is protected by the 7 1/2-ampere BU VOW
circuit breaker in the overhead circuit breaker panel (fig.
2-8). The back-up voice order wire shares an antenna
mounted on the aircraft belly with the transponder (fig.
2-1 and 2-2).
3-10. VHF COMMUNICATIONS TRANSCEIVERS
Introduction. The VHF communications
communications on 1360 channels from 118.00 through
151.975 MHz, and are operated by two CTL-22
transceiver control units, located on the pedestal
extension (fig. 2-14).
The solid-state transceiver includes capture-
effect automatic squelch to help prevent missed radio
calls, plus audio leveling and response shaping to
ensure audio quality. Transmitter sidetone comes from
detected transmitter signal, and is therefore a reliable
check of transmission quality. Each VHF transceiver is
powered through its respective circuit breaker, placarded
VHF # 1 or VHF # 2, located on the overhead circuit
breaker panel (fig. 2-9).
(VHF-22B). All operating controls for the transceivers
are located on the CTL-22 transceiver control units and
on the FM/AM alternate communication switch panel
(pedestal extension, fig. 2-14).
Active frequency display. Displays
the active frequency (frequency to which the transceiver
is tuned) and diagnostic messages.
switch is a three-position spring-loaded toggle switch
placarded XFRI MEM, which when held to the XFR
position, causes the preset frequency to be transferred
up to the active display and the transceiver to be
returned. The previously active frequency will become
the new preset frequency and will