5. Communications Flashcards
Radio Tuning Panel OFF Switch
Disconnects the panel from the communication radios
Offside Tuning Light
- The radio normally associated with this panel is being tuned by another Radio Tuning Panel or,
- The Radio Tuning Panel is being used to tune a radio not normally associated with this radio tuning panel
VHF Test Switch
- Removes automatic squelch feature, permitting reception of background noise, testing receiver operation,
- Improves reception of weak signals
AM Switch and Light
- Illuminates: HF AM is in use,
- Distinguished: HF USB in use,
- USB: Upper Side Band
Keyline Timer
- Limits VHF transmission to approximately 35s,
- After 25-30s after any PTT selected, transceiver make an aural tone in the headset,
- Tone continues for 5s and after it stops RF transmission stops,
- Then radio is set to receive mode automatically,
- Radio remains in receive mode until PTT is released and selected again
Service INTERPHONE Handset Jack
- Positioned above the PA Hand Mike Jack,
- Used to directly communicate on SERVICE INTERPHONE,
- Bypasses ACP
Voice Recorder ERASE Switch
To erase:
- Push 2s,
- Operates only on the ground and,
- Parking Brake Set
Voice Recorder TEST Switch
To test:
- Push for 5s,
- Status light flashes once,
- A tone may be heard through headset
Voice Recorder Switch AUTO
Powers CVR from first engine start until 5 minutes after last engine shutdown
Master Call Lights in Cabin
- Pink: Flight Deck or other Flight Attendant Station is calling,
- Blue: A Passenger seat call switch activated,
- Amber: A Lavatory call switch is activated
Call RESET Switch
- Extinguishes both pink master call lights,
- Cancels call,
- Disconnect headset from PA system
Audio Warnings
- GPWS, Altitude Alert, Traffic Collision and PWS alerts,
- Heard through the speakers and headsets at preset volumes,
- They cannot be controlled or turned off
Speaker Muting
- Muted for CPT and F/Os PTT microphone operation,
- Not muted for Oxygen Mask microphone operation
Oxygen Mask Microphone
- For some airplanes it’s enabled and boom mic disabled when left oxygen mask door is open,
- It’s disabled and the boom mic enabled when left oxygen mask door closed and RESET/TEST switch is pushed
Normal Audio System Operation
- Located in a common Remote Electronics Unit in the E/E compartment,
- They function independently
Degraded Audio System Operation
- If the Remote Electronics Unit or ACP fails, the ACP cannot control the Remote Electronics Unit,
- Audio system can be switched to a Degraded mode by the ALT-NORM switch,
- In ALT mode, the ACP at that station is inoperative and crew member can only communicate on one radio,
- Transmitter selector of the usable radio illuminates,
- Only usable radio heard at a preset volume through the headset,
- Speaker is not functional on that station,
- Flight and Service interphones cannot be used,
- Hand mic is not usable,
- Mask and Boom mics and MASK-BOOM switch works normally,
- Altitude Alert, GPWS and Windshear alerts are heard
Degraded Audio System Default Radios
- CPT: VHF-1,
- F/O: VHF-2,
- Observer: VHF-1
VHF Communications Antennas
- VHF-1: Upper Fuselage,
- VHF-2/3: Lower Fuselage
CVR
- Uses 4 independent channels (Flight Deck Area Conversations, others ACP output audio and transmissions),
- Records audio for last 120 minutes,
- Equipped with Locator Beacon operable for 90 days
ACARS
ARINC Communications Addressing and Reporting System
CPDLC
Controller-Pilot Data Link Communications
SATCOM
- Some aircrafts has it,
- Provides only datalink communication,
- CDU connects to SDU,
- ACARS management unit connects with SDU to send and receive data signals
