Northern Airborne Technology AMS50 - Manual (Page 27)

SM50 Rev. 4.00 AMS50-000 Stereo Audio Panel with Marker Manual
2.3.8
Post-Installation Checks
2.3.8.1 Voltage/resistance checks
Do not attach the AMS50 until the following conditions are met.
Check the following:
Check P101, pin <20> for dimmer buss voltage relative to ground (28 V installations). a)
b)
c)
d)
Check P101, pin <21> for dimmer buss voltage relative to ground (14 V installations).
Check P101, pin <22> for +11 to 33 Vdc relative to ground.
Check P101, pins and for continuity to ground (less than 0.5 Ω).
Check P201, pins and for continuity to ground (less than 0.5 Ω) with
the remote select switch activated to the relevant position. e)
2.3.8.2
Power On checks
Install the AMS50 and power up the aircraft’s systems. Verify normal operation of all
functions. Refer to Section 3 (Operation) for specific operational details.
a) Begin with only the Pilot's headset installed, no hand mic. Check for correct
radio operation, both receive and transmit. Check yoke (or cyclic) switch action.
Check radio audio inputs and selection of same.
b) If there is a music source in the system turn it on and verify that music is muted in the
CREW mode and removed in the PLT ISO mode. Check for proper mute operation.
Note: Unusual buzzes, hums or other background audio are symptomatic of multiple
grounds, or noisy external systems such as blowers or pumps sharing wiring
with the audio system. Failure to key or correctly modulate a transmitter is
often the result of forgetting to connect all required grounds to the radio or
external audio system.
c) Check the ICS Modes (ALL, CREW, PLT ISO), and the SPLIT transmit selection
and manual Fail-safe operation.
d) Plug in the Co-pilot's headset. Check for correct ICS and SPLIT transmit
operation. Check that the Co-pilot looses transmit capability during PLT ISO.
Check yoke switch functions.
e) Plug in the hand mic, if installed, and test for correct operation in all modes.
f) Plug in any remaining headsets, and check for correct ICS operation.
Note: Incorrect jack wiring is a common fault for rear passenger stations, and
may cause a wide range of problems.
No 12, 2003 Page 2-9
ENG-FORM: 805-0104.DOT
Amendment # 2 Mar 20, 2006
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.