SM48 Rev. 4.00
AA86/87 Stereo Intercom Manual
Nov 12, 2003
Page 3-3
ENG-FORM: 806-0104.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
3.2.3
MUSIC Vol, MUSIC Mute and Isolate Controls
The MUSIC Vol, MUSIC Mute and Isolate controls are dual concentric potentiometer
assemblies with an integral push on/push off switch.
3.2.3.1
Music Volume
The automatic music muting feature of the AA86/87 intercom makes it necessary to set
the initial/maximum music volume when neither the radio audio nor any microphone
input is active. Alternatively, the Music Mute control may be rotated to its non-muting,
fully clockwise position. (See section 3.2.3.2)
If the stereo music source also includes a volume control, it is recommended that the
AA86/87 Music Volume control is set at a nominal position, and that further volume
changes be made by adjusting the control provided on the music source.
3.2.3.2
MUSIC Mute
Rotating the Music Mute control fully clockwise
gives
minimum
music muting (i.e. full
music volume) and full counterclockwise
rotation represents
maximum
muting
(i.e. total
muting or zero music volume).
The interaction between the Music Volume and Music Mute controls described in
section 3.2.3.1 requires that the initial (maximum) music volume should be set prior to
setting the music mute level.
The Music Mute control determines the depth of muting; that is, the music volume when
the radio audio is active and/or when someone in the aircraft is speaking on the
intercom. The Music Mute control may be adjusted for the desired 'background' level
when either the radio audio input or any intercom mic is active.
3.2.3.3
Pilot Isolate
The Isolate function of the intercom is controlled by pushing the smaller (inner) portion of
this knob. Each switching action will change the state of the AA86/87 between the
isolate and non-isolate configurations, and the
indicator lamp located to the right and
below the Pilot Isolate switch (when the intercom is in its horizontal position) illuminates
green to indicate that Pilot Isolate
mode has been selected. This indicator also
functions as a Co-Pilot PTT indicator, and lights red during Co-Pilot PTT operation.
Pilot Isolate functions to completely isolate the pilot from the passengers (including the
co-pilot). The pilot will not hear any other lntercom user or music. Similarly, the co-pilot
and remaining users, while hearing each other and the music, will not hear the pilot or
the radio audio.
