Northern Airborne Technology AA20-431 - Manual (Page 13)

AA20-431 Cabin PA System Manual SM22 Rev. 4.10
2.3.7.7 Music
Select
The position of the MUSIC SEL jumper is determined by the type of music input. The jumper
should be ‘in’ (shorted) if a portable cassette tape/CD player is attached. The jumper should
be ‘out’ (open) if a remote CD changer/am/fm cassette player is attached.
Note: The unit ships from the factory with the jumper ‘in’.
2.3.8
Post-Installation Checks
2.3.8.1 Voltage/Resistance Checks
Do not attach the AA20-431 until these conditions are met.
Check the following:
a) J101
pins <1> and <2> for +28 Vdc relative to ground.
b) J101 pin <3> for +28 Vdc relative to ground with cabin lights full ‘on’.
c) J101 pins <4> and <5> for open circuit to ground and each other (greater than
10 M Ω).
d) J101 pins <4> and <5> for open circuit to pin <23> (greater than 10 M Ω).
e) J101 pins <20>, <21> and <22> for continuity to ground (below 0.5 ohms).
2.3.8.2
Power On Checks
a)
Install the AA20-431 and connect a music source to the system. Power up the
ship's systems and turn on all required radios and accessories.
b) Set the AA20-431 SPKR switch to PA. Music should be heard in the headsets
but not over the speaker.
c) Key the PA. The music should mute and a chime should be heard over the
speaker and in the headsets. Speak into the microphone. Audio should be
heard over the speaker and in the headsets.
d) Set the AA20-431 SPKR switch to MUSIC. Music should be heard over the
speaker and in the headsets.
e) Key the PA. The music should mute and a chime should be heard over the
speaker and in the headsets. Speak into the microphone. Audio should be
heard over the speaker and in the headsets.
f) Activate, then de-activate the Seatbelt, No Smoking and Message keys in turn.
The music should mute and chime should be heard on activation and de-
activation.
Page 2-4 Apr 21, 2004
ENG-FORM: 805-0106.DOT
Amendment #1 Jan 1 8, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.