Com Audio (Gtn 635/650 Only) - Garmin GTN 625 Installation Manual

5.2.12 COM Audio (GTN 635/650 Only)

5.2.12.1 COM Audio Function
Activation of MIC 1 TRANSMIT enables MIC 1 AUDIO IN HI and causes the transceiver to transmit.
500 COM AUDIO is a 100 mW audio output that is intended to drive a headset or an audio panel.
5.2.12.2 COM Audio Electrical Characteristics
5.2.12.2.1 COM Mic Audio (GTN 635 and GTN 650 Only)
COM MIC 1 AUDIO IN HI
MIC AUDIO IN LO
COM MIC 1 AUDIO IN HI is standard carbon or dynamic mic input with integrated preamps providing
minimum 70mVrms into a 1000Ω load.
COM MIC 1 AUDIO IN HI is set in the factory so that 100 mVrms modulates the transmitter to 85%
nominally at 1000 Hz. The microphone gain adjustment is made through Configuration Mode. See
Section 6.6.11.
5.2.12.2.2 COM Audio
500 COM AUDIO HI
500 COM AUDIO LO
500 COM AUDIO supplies 100 mW into a 500 load. This is a balanced output and the LO output must
be connected.
500 COM AUDIO is the summation of the COM receiver audio, COM sidetone audio, and intercom
audio.
GTN 625/635/650 TSO Installation Manual
Page 5-24
Pin Name
Pin Name
Connector Pin I/O
P1003 5 In
P1003 20 In
Connector Pin I/O
P1003 7 Out
P1003 18 Out
190-01004-02
Rev. F