G900X/G950 Installation and Maintenance Manual – GMA 1347
Page 3-3
190-00719-00
Revision D
3.2
Electrical
Specifications
Table 3-1. GMA 1347 Electrical Specifications
Characteristics
Specifications
Power Requirements
14/28 VDC See the Environmental Qualification Form for details on surge
ratings and minimum/maximum operating voltages. See Table 1-2 for
current specifications.
Audio Panel
Transceiver inputs: 3
Receiver inputs: 5
Unswitched inputs: 4
Input impedance: 500
Ω
Input isolation: 60 dB minimum
Special functions: Failsafe operation
MASQ
TM
processing
Intercom
Positions: 6 (pilot, copilot, 4 passengers)
Volume controls: 2 (pilot, copilot/passengers)
VOX level controls: 2 (pilot, copilot/passengers)
VOX circuits: 6 (one per mic input)
Music inputs (stereo): 2 (one input mutable)
Music input impedance: 5 k
Ω
Music input level: Less than 500 mVAC RMS for full output (typical).
1 VAC RMS MAX (3 V p-p)
Microphone signal processing: 9 pole characteristic and special cabin
noise band de-emphasis
Intercom isolation modes: 4 (All, Pilot Isolate, Copilot Isolate, Crew
Isolate)
Special functions: Recorder with playback (automatic recording of
selected COMs) up to 2.5 minutes of recording time.
Automatic squelch: 6 (one per mic input) pilot selectable between auto
and manual.
Headphone Outputs
Output amplifiers: 3, stereo (pilot, copilot, passengers)
Fidelity: Power into 150
Ω
Distortion
50 mW <0.5%
100 mW <5%
Frequency response: music; 50 Hz to 20 kHz nominal
Aircraft radio: 200 Hz to 6 kHz nominal
ICS mic: (Special cabin noise band de-emphasis)
Speaker Outputs
Outputs selectable: 1, pilot selectable
Output power: 10 watts into 4
Ω
or 8
Ω
, @ any normal supply voltage.
Frequency response: 350 Hz to 6 kHz nominal
Special functions: PA Mode, pilot selectable, including split operation
Marker Beacon Receiver
Frequency: Crystal controlled at 75 MHz
Sensitivity: LO 1000
μ
V; HI 200
μ
V
Selectivity: 6 dB @ ±10 kHz min, 40 dB @ ±200 kHz max.
Input impedance: 50
Ω
External lamp drive: 125 mA max each output
Other outputs: Middle MKR sense
Special functions: SmartMuteTM marker audio muting