Beechcraft C-12C Operator And Technical Reference Manual page 358

TM 1-1510-218-10
(a) VHF
microphone signals to the #1 VHF transceiver.
(b) VHF
microphone signals to the #2 VHF transceiver.
(c) HF – Permits reception of audio from
the HF transceiver and routes key and microphone
signals to the HF transceiver.
(d) V/UHF – Permits reception of audio
from the V/UHF transceiver and routes key and
microphone signals to the V/UHF transceiver.
(e) PA – Permits cabin paging.
c. Operation.
(1) Turn-on Procedure. The audio pilot and
copilot control panel is on whenever electrical power is
applied to the aircraft and the AVIONICS MASTER
POWER switch is ON.
(2) Interphone Operating Procedure.
1. Transmitter Selector Switch – PA.
2. Microphone Switch – Press (listen for
sidetone).
3. VOLUME Control – Adjust sidetone
and interphone
headphone.
(3) Navigational Aid and Receiver Monitoring
Procedure.
1. Pilot and Copilot Switches – As
required.
2. VOLUME Control – Adjust volume
control of system being monitored.
(4) Transmitting Procedure.
1. Transmitter Selector Switch – As
required.
2. Microphone Switch – Press (listen for
sidetone).
3. Applicable
Control – Adjust for comfortable audio
level.
3C-4
1 – Routes key
2 – Routes key
audio level
Transceiver VOLUME
and 3C-7. AUDIO CONTROL PANEL
a. Description.
and located on the instrument panel, Figure 2-17, contains
controls and switches which provide the pilot and
copilot with a means of selecting desired reception and
transmission sources, and also a means of controlling
the volume of audio signals received from interphone,
communication, and navigation systems.
Figure 3C-2.
V/UHF, or HF transceivers. The audio control panel is
fed through two 2-ampere circuit breakers, placarded
AUDIO PILOT and COPILOT, located on the
overhead circuit breaker panel, Figure 2-16.
b. Controls and Functions.
(1) Pilot
Switches. The pilot and copilot are each provided with
a set of the following list of receiver audio switches,
which are located across the top of the audio control
panel. These two position switches permit monitoring
of the selected audio facility.
listed in this paragraph using their placarded names.
The switches are moved to the up position to select
the desired audio facility and down to the off position,
which is placarded either PILOT AUDIO OFF or
COPILOT AUDIO OFF.
(a) VHF 1 Switch – Permits monitoring
of VHF 1 audio.
in
(b) VHF 2 Switch – Permits monitoring
of VHF 2 audio.
(c) HF – Permits monitoring of HF
audio.
(d) V/UHF Switch – Permits monitoring
of the ARC-210 audio.
(e) NAV 1 Switch – Permits monitoring
of the NAV 1 audio.
(f) NAV 2 Switch – Permits monitoring
of NAV 2 audio.
(g) MKR BCN 1 Switch – Permits
monitoring of marker beacon 1 or 2 audio.
(h) MKR BCN 2 Switch – Permits
monitoring of marker beacon 1 or 2 audio.
(i) DME/TACAN
monitoring of DME/TACAN audio.
(j) ADF 1 Switch – Permits monitoring
of ADF 1 audio.
T2 .
The audio control panel,
The user selects between the VHF,
and Copilot Receiver
These switches are
Switch
Refer to
Audio
– Permits