Northern Airborne Technology AMS50 - Manual (Page 25)

SM50 Rev. 4.00 AMS50-000 Stereo Audio Panel with Marker Manual
2.3.7 Adjustments
See Adjustment Hole Marks drawing AMS50\000\908-0 at the end of this section of
the manual for all adjustment locations.
The unit ships from the factory with all internal adjustments set to the normal test levels.
Once installed in the aircraft, it may be desirable to change some of these settings to
best suit the local operating environment.
CAUTION
Before performing the following adjustments ensure receive (radio) audio
source is set to produce 2.5 Vrms
±10 % at the input to the AMS50, or the
mute functions may not operate correctly.
2.3.7.1 Music Mute
The music mute level sets the volume that the music will drop to during a music mute
condition. There are separate level adjustments for the crew (C MUSIC MUTE) and
passengers (P MUSIC MUTE).
To set the mute level, set the AMS50 to ALL mode and the VOX knob to live (fully ccw).
Inject music and adjust the associated mute trim pot to set the desired level of muting
(cw to increase and ccw to decrease). The fully ccw position gives a minimum muting
of 30%. At 12 o’clock the muting level is 50% and at fully cw the muting level is 100%
(music fully muted).
Note: In CREW mode, the crew's music level is automatically set to the muted level
selected above.
Nov 12, 2003 Page 2-7
ENG-FORM: 805-0104.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.