Northern Airborne Technology AA9x - Manual (Page 47)

AA9x Series Single Channel Audio Controller
SM56 Installation and Operation Manual
Section 3 Rev: 1.00 Issue 4 Page 3-4
3.3.3.1 LIVE (Hot Mic Operation)
ICS mode switch (orange switch bat) set to the up (VOX) position and the VOX squelch control set to the
full counter-clockwise position.
3.3.3.2 KEYED ICS (PTT Operation)
ICS toggle switch (orange switch bat) set to the down (KEY) position. In some models of AA9x audio
controllers, set the VOX squelch control to the full clockwise position. Keyed ICS is inherent to the pilot
and copilot microphone circuits only. Passenger microphone circuits will be LIVE with this mode selected.
3.3.3.3 VOX (Voice Activated)
ICS toggle switch (orange switch bat) set to the up (VOX) position. Set the ICS VOX Squelch control fully
counter-clockwise and then slowly rotate clockwise until the intercom just becomes quiet. This setting will
vary with ambient noise conditions and the quality and number of microphones connected in the system.
3.3.3.4 General ICS Functions
Passenger ICS audio is LIVE when the controller is in the LIVE or KEYED mode of ICS operation. In the
KEYED mode of operation the passenger microphones are LIVE. Utilize drop cord assemblies
incorporating microphone circuit interrupt switches for keyed ICS operation. Passenger ICS is VOX
triggered when VOX mode is selected.
All ICS audio is controlled by the front panel ICS volume control and may be varied to suit conditions. The
ICS VOL control provides adjustment from approximately 1% to full output.
In the AA95 and AA97 models the mode switch (red switch bat) is used to select between NORMAL and
PILOT ISO/EMR modes. In the NORMAL position (down), all operations of the ICS are functional as
described above. When the switch is in the pilot isolate/emergency position (PILOT ISO/EMR), the pilot is
isolated from the rest of the passengers. If the controller is operated in the ISO/EMR mode, ICS operation
will continue (if there is no fault condition) between the passengers and copilot, but will exclude the pilot.
See Section 3.5 for further details.
3.4 Optional Features
ENG-FORM: 806-0111.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
Some of the more common optional features can be seen on the AA95-728 (shown in Figure 4, section
3.3.3) and Figure 5 below.
Figure 5: AA95-729