190-01878-02
GMA 342/345 Installation Manual
Rev. 5
Page 4-5
4.4 Lighting Bus
The GMA 342/345 can be configured to track a 14 or 28 Vdc lighting bus using these inputs. Refer to
for lighting interconnections.
Backlighting refers only to the lighting of the text labels on the front panel and is controlled by the inputs
in Table 4-4. The brightness of the LED annunciators that illuminate each key when selected is controlled
by a photocell that operates independently of the backlight input.
NOTE
If the lighting bus inputs are not connected, the backlighting will use the photocell.
4.5 RS-232
The RS-232 outputs conform to EIA Standard RS-232C with an output voltage swing of at least ±5V when
driving a standard RS232 load.
4.6 Audio Inputs/Outputs and Mic Keys
4.6.1 Mic Audio Inputs and Mic Keys
Table 4-4 Lighting Bus
Pin
Connector
Pin Name
I/O
5
J3402
LIGHTING BUS 14V LO/28V LO
--
6
J3402
LIGHTING BUS 14V HI/28V LO
IN
7
J3402
LIGHTING BUS 14V HI/28V HI
IN
Table 4-5 Lighting Bus
Pin
Connector
Pin Name
I/O
17
J3402
RS-232 IN
IN
18
J3402
RS-232 OUT
OUT
Table 4-6 Mic Audio Inputs and Mic Keys
Pin
Connector
Pin Name
Description
I/O
34
J3401
PILOT MIC KEY* IN
Enables respective MIC audio into
the selected transceiver unit
IN
33
J3402
COPILOT MIC KEY* IN
IN
33
J3401
PILOT MIC AUDIO IN HI
Pilot Mic audio input and ground
reference
IN
35
J3401
PILOT MIC AUDIO IN LO
--
32
J3402
COPILOT MIC AUDIO IN HI
Copilot Mic audio input and ground
reference
IN
34
J3402
COPILOT MIC AUDIO IN LO
--
35
J3402
PASS 1 MIC AUDIO IN HI
Passenger 1 Mic audio and ground
reference
IN
36
J3402
PASS 1 MIC AUDIO IN LO
--
