Northern Airborne Technology AA85 - Manual (Page 21)

SM38 Rev. 4.10 AA85 InterVOX II™ Intercom Manual
Jun 9, 2004 Page 2-7
ENG-FORM: 805-0106.DOT
Amendment #2 Apr 11, 2006
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
2.3.6.1 RECEIVE LEVEL
The minimum volume level of receive audio is controlled separately for the passengers
and crew. The crew setting can be adjusted by potentiometer RECEIVE LEVEL C. The
crew setting can not be fully muted. The passenger setting can be adjusted by
potentiometer RECEIVE LEVEL P. The passenger level can be fully muted, if desired.
The cw rotation of either of these controls will increase receive audio volume level.
Adjust the crew setting in both CREW and PLT ISO modes to ensure satisfactory levels
in both modes.
Note: If the radio TX sidetone seems too loud, it may be necessary to ‘balance’ the
radio RX audio, TX sidetone, and AA85 Receive level ‘C’.
2.3.6.2
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 and passengers. The
crew setting can be adjusted by potentiometer MUSIC MUTE C. The passenger setting
can be adjusted by potentiometer MUSIC MUTE P.
To set the mute level, set the AA85 to ALL mode and the associated VOX knob to live
(fully ccw). Inject music and adjust the associated mute trim pot to adjust the amount of
muting (cw to increase and ccw to decrease). The fully ccw position gives a minimum
muting of 25%. At 12 o’clock, the muting level is 50% and at fully cw the muting level is
100%.
2.3.7
Adjustment procedure
2.3.7.1 To set the configuration desired, see the applicable drawings as listed in
section 2.5.
2.3.7.2
Inject radio audio as adjusted in section 2.3.6, inject music (if being used
in the installation) and then listen to a crew headset. Adjust RECEIVE
LEVEL C until the desired level is reached. The music should be muted.
2.3.7.3
Listen to a PAX headset and adjust RECEIVE LEVEL P until the desired
level is reached.
2.3.7.4 Discontinue
the radio injection.
2.3.7.5
Put on a crew headset. Adjust MUSIC MUTE C until the desired level is
reached, while speaking into the mic.
2.3.7.6
Put on a PAX headset. Adjust MUSIC MUTE P until the desired level is
reached, while speaking into the mic.