Garmin GMA 342 Installation Manual page 48

4.6.5 Failsafe Warning Audio
Failsafe audio is audio from another device that is heard when the GMA 342/345 is in failsafe mode
(power off or unit failure) and is desired to be heard in addition to the COM audio.
Pin Connector
29 J3402
14 J3402
CAUTION
During failsafe mode both FAILSAFE WARN AUDIO IN HI and COM 1 AUDIO INPUT
are connected to the PILOT HEADSET LEFT OUTPUT. When in failsafe the output of the
COM 1 radio and the output of the device connected to FAILSAFE WARN AUDIO IN HI
will become shorted together, potentially causing damage or interference. If the
FAILSAFE WARN AUDIO IN HI is used, it may be necessary to install summing resistors
in series between these sources and the inputs to the audio panel to protect the outputs
from damage.
4.6.6 Music Inputs
The MUSIC LO signals are not the same reference as other ground connections. The MUSIC LO signals
should be used as part of a differential pair (along with the MUSIC RIGHT and MUSIC LEFT signals). If
the MUSIC LO signal is tied to a ground connection, the music will contain noise, and the audio quality
will be degraded.
Pin Connector
23 J3402
24 J3402
25 J3402
26 J3402
27 J3402
28 J3402
190-01878-02
Rev. 5
Table 4-11 Failsafe Warning Audio
Pin Name
FAILSAFE WARN AUDIO
IN HI
ALERT 2 LO, FAILSAFE
AUDIO IN LO
Table 4-12 Music Inputs
Pin Name
MUSIC 1 IN LEFT
MUSIC 1 IN RIGHT
MUSIC 1 IN LO
MUSIC 2 IN LEFT
MUSIC 2 IN RIGHT
MUSIC 2 IN LO
Description
In the event of power loss, if wired,
failsafe warning audio will be heard in the
Pilot's Left headset in addition to the
COM1 Audio Input.
Ground Reference for Failsafe Warning
Audio Input
Description
Music 1 Input
Differential Reference for Music 1
Music 2 Input
Differential Reference for Music 2
GMA 342/345 Installation Manual
I/O
IN
--
I/O
IN
--
IN
--
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