COMMUNICATIONS Flashcards
What does selecting a radio transmitter switch do?
Transmitter selector switches illuminate when the respective transmitter is active. Only one transmitter may be selected at a time. A microphone is then used to transmit over the selected transmitter. Reception is enabled when a transmitter is selected, regardless of the position of the receiver switch below.
What is the purpose of the ALT-NORM switch on the ACP?
The ACP may be placed in degraded mode using the ALT/NORM switch.
ALT allows for alternate operation (degraded mode) in the event of an ACP panel malfunction. In degraded mode, the ACP transmitter selectors are not functional. The receiver selectors are not functional and only the usable radio is heard at a preset volume, through the headset.
In degraded mode, the following ACP is latched to the associated radio as follows:
• ACP 1 to VHF 1
• ACP 2 to VHF 2
• ACP 3 to VHF 1
What is the purpose of the VHF TEST switch?
The VHF TEST switch removes the automatic squelch feature, permitting reception of background noise and thereby testing receiver operation. Removing the automatic squelch improves the reception of a weak signal.
What does the white offside tuning light indicate on the RTP?
If any transceiver other than the onside VHF or HF radio is selected, the white offside tuning light will illuminate at the top of the RTP.
What is the indication of a radio failure?
If the transceiver has failed, the two frequency indicators show FAIL. This indicates a failed radio.
What is the indication of an RTP failure?
The frequency indicators show PANEL FAIL when there is an internal failure of the RTP.
Which switch is used to key transmission over the selected transmitter?
Each hand microphone has a PTT switch
Selecting RADIO on the associated ACP, MIC PTT on the glareshield or PTT on the control wheel for headset
boom transmissions.
What is the purpose of the PA hand mic on the aft electronic panel?
This handset is only used to make a Passenger Address. Use of the PA handset bypasses the ACP and allows pilots to make a PA regardless of ACP selection.
What precautions, if any, should be taken when keying an HF radio on the ground?
Do not key the HF radio while the aircraft is being fueled/ defueled. Injury to personnel or fire may result.
Ensure that personnel stay a minimum of 10 ft from the vertical stabilizer when the HF system transmits. Energy from the antenna can cause injuries. Do not operate the HF radio while the aft service door or entry doors are opened.
How is an incoming SELCAL indicated?
A white call (C) light illuminates on the ACP associated transmit switch and a chime sounds.
How are the MEDLINK headset jacks controlled?
Control for the MEDLINK headset audio is the observer’s ACP (ACP3).
What is the purpose of the service interphone switch on the aft overhead panel?
External jacks for use by Maintenance or Service personnel can be added to the system by use of the SERVICE INTERPHONE switch on the aft overhead panel.
How are incoming calls from the passenger cabin handsets indicated?
Pushing 2 on the handset calls the Flight Deck, sounds a chime, and illuminates the CABIN call light on the ACP.
What does the GRD CALL switch do when pushed?
The GRD CALL switch sounds a horn in the nose wheel well while the switch is selected.
What does the ATTEND switch do when pushed?
This sounds a two-tone chime in the Passenger Cabin and illuminates both pink Master Call lights in the Passenger Cabin.
