190-00917-01
GMA 240 Installation Manual
Rev. D
Page 1-3
1.3.2 Electrical Characteristics
Table 1-2 Electrical Characteristics
Characteristic
Specification
Temperature
Range
-20 C to +55 C (operation)
-55 C to +85 C (storage)
Altitude
55,000 Feet
Audio Panel
Functions
Dedicated Transceiver inputs: 3 (including TEL)
Dedicated Receiver inputs: 4 (all independently selectable)
Alert (unswitched) inputs: 3 (each with configurable volume)
Input impedance: 500
Ω
Input isolation: 60 dB minimum
Alert/Receiver/Transceiver bandwidth: 100 Hz to 6.5 kHz
Special functions: Fail-safe operation
MASQ™ processing (Master Avionics Squelch)
Configurable button push aural annunciation
Intercom Functions
Positions: 4 (pilot, copilot, 2 passengers)
Volume controls: 3 (pilot, copilot/passengers, music)
VOX level controls: 2 (pilot, copilot/passengers)
VOX circuits: 4 (one per mic input)
Microphone input impedance: 450
Ω
(compatible with 150 to 600
Ω
mics)
Microphone bias voltage: about 10 Vdc delivered through 450
Ω
Microphone response: 9-pole characteristic cabin noise de-emphasis
Intercom isolation modes: 2 - all, pilot (or configure for all, crew)
Telephone interfaces: 1 full-duplex (use LRU pins or front jack)
Headphone
Outputs
Output amplifiers: 2 stereo (pilot, copilot/passengers)
Fidelity: Load Power Distortion (typ.)
150
Ω
50 mW <0.03% THD+N
150
Ω
100 mW <0.07% THD+N
50
Ω
150 mW <0.07% THD+N
50
Ω
300 mW <0.10% THD+N
Compatible with higher headphone impedances, those shown are for worst-case
distortion and bandwidth
