3Com SM69 Stereo System User Manual

SM69
AA12S Series
Compact Audio Controller
INSTALLATION AND OPERATION MANUAL
REV 4.00 October 13, 2005
Northern Airborne Technology Ltd.
1925 Kirschner Road
Kelowna, BC, Canada.
V1Y 4N7
Telephone (250) 763-2232
Facsimile (250) 762-3374
Copyright 2005 by Northern Airborne Technology
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
AA12S Series Compact Audio Controller Manual
Periodically NAT will release manual amendments. In order to maintain the most
accurate and up to date manual these amendments should be carried out immediately
upon receipt and recorded on the following amendment record.
AMENDMENT RECORD
Amendment Amendment
Number
Date
806-0001
Oct 14/05
Section(s)
Changed
1,3
Date
Entered
Entered By
Performed at factory
Insert any Amendment Instruction sheets after this page.
Oct 13, 2005
Page ii
ENG-FORM: 820-0109.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
INSTALL_OPS
MANUAL AMENDMENT
Manual: SM69 (AA12S)
Document # SM69\Install_Ops\809-0001
Amendment #: 1
Amendment Date: Oct 14, 2005
The purpose of this amendment is to change the Revision of the manual to 4.00 (to
reflect its status as a 2-part manual), and to correct a Direct Audio statement (removed
from Section 3.3.1, added to Section 1.2.1.
NB. This amendment can be performed on both Rev 1.00 OR Rev 4.00 of this manual.
Amendment Instructions:
Remove Pages
Replace With Pages
1-1 and 1-2 Rev 1.00 or 4.00
3-1 to 3-4 Rev 1.00 or 4.00
1-1 and 1-2 Rev 4.00 Amendment # 1
3-1 to 3-4 Rev 4.00 Amendment # 1
1
2
Update the Amendment Record sheet at the front of the manual.
3
Insert this page into the manual after the Amendment Record sheet (page ii).
Manual Amendment ends after the following amended pages
Amendment # 1
Oct 14, 2005
Page 1
ENG-FORM: 809-0109.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
AA12S Series Compact Audio Controller Manual
Table of Contents
Section
Title
1
Description
1.1
1.2
1.2.1
1.2.2
1.3
1.3.1
1.3.2
1.3.3
1.3.4
Introduction
General Information
Features
Installation Adjustments
Specifications
Electrical Specifications
Physical Specifications
Environmental Specifications
Unit Nomenclature
2
Installation
2.1
2.2
2.2.1
2.3
2.3.1
2.3.2
2.3.3
2.3.4
2.3.5
2.3.6
2.4
2.5
2.6
Introduction
Unpacking and Inspection
Warranty
Installation Procedures
Warnings
Cautions
Notes
Cabling and Wiring
Post-Installation Checks
Adjustments
Continued Airworthiness
Accessories Required But Not Supplied
Installation Drawings
3
Operation
3.1
3.2
3.2.1
3.2.2
3.3
3.3.1
3.3.2
3.3.3
3.3.4
3.3.5
Introduction
General Information
Features
Installation Adjustments
Operation Specifics
Radio Selection
Intercom
PILOT ISO / NORM Modes
Entertainment Audio
Automatic Fail-safe
Oct 13, 2005
Page
1-1
1-1
1-1
1-1
1-2
1-2
1-4
1-4
1-5
2-1
2-1
2-1
2-1
2-1
2-2
2-2
2-2
2-2
2-3
2-4
2-4
2-5
3-1
3-1
3-1
3-1
3-2
3-2
3-3
3-4
3-4
3-5
Page iii
ENG-FORM: 820-0109.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
AA12S Series Compact Audio Controller Manual
Section 1 Description
1.1
Introduction
Information in this section consists of the functional and operational procedures for the
AA12S Series Compact Audio Controllers.
The information in this manual is applicable to all models unless otherwise specified.
1.2
General Information
The AA12S is a compact Dzus-mounted audio controller with an integral 4-place stereo
voice-activated intercom. It provides intercom capabilities for the pilot, co-pilot and two
passengers (PAX). The AA12S accepts stereo music inputs from either portable or
fixed entertainment systems to produce high quality stereo headset output.
Radio functions include selectable transmit capability for pilot and co-pilot on 3 COM
radios and a PA. Receive audio selections include COM1, COM2, COM3, MKR, NAV,
ADF, and DME.
1.2.1
Features
All four mics have individual VOX gating. Each gate may also be activated with the
corresponding ICS keyline.
ICS muting is automatic during radio transmission.
The unit is supplied to suit a standard NAT bidirectional ICS audio TIE line for multi-unit
interface (configuration dependent). The crew and PAX are always connected except in
the case of Pilot ISO mode, when the pilot is disconnected from the ICS tie line.
If required, one or more receiver audio inputs may be configured at the factory prior to
ordering as (an) unswitched Direct Audio input(s). A new part number may be
assigned. Contact NAT Product Support for further information.
1.2.2
Installation Adjustments
The following audio levels can be adjusted at the time of installation, or during service
by an approved dealer, using individual level trimpots.
•
Music Mute level
•
Sidetone level
•
ICS Bass level
•
ICS Balance
•
RX volume level
•
RX Balance
•
Music Bass level
•
Music Balance
Oct 13, 2005
ENG-FORM: 800-0107.DOT
Page 1-1
Amendment # 1
Oct 14, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
AA12S Series Compact Audio Controller Manual
1.3
Specifications
1.3.1
Electrical Specifications
Power Supply
Input voltage
Internal supply
SM69 Rev. 4.00
11-30 Vdc operating. Linear regulator with
reverse and over voltage protection.
11 Vdc
Nominal Lighting Voltage 27.5 Vdc @ 200 mA max (AA12S-001)
13.5 Vdc @ 400 mA max (AA12S-004)
Nom. Operating Voltages 27.5 Vdc @ 600 mA max
(one input for both) 13.8 Vdc @ 600 mA max
Maximum Operating
30.3 Vdc
Minimum Operating
11.0 Vdc
Note: The AA12S is not designed to operate under emergency electrical system
conditions for 14 Vdc operation.
Input Signals
Mic:
Quantity
Rated level
Impedance
Circuitry type
4 (Pilot, Copilot, 2 Passengers)
250 mVrms nominal (125 to 500 mVrms)
150 Ohm ±10 %
unbalanced
TX Keyline:
Quantity
Rated level
2 (Pilot, Copilot)
ground activates keyline, <20 mA source current
ICS Keyline:
Quantity
Rated level
4 (Pilot, Copilot, 2 Passengers)
ground activates keyline, <1 mA source current
Receive Audio:
Quantity
Rated level
Impedance
Circuitry type
7 (3 COM, 4 NAV)
2.5 Vrms nominal (1.3 to 5.0 Vrms)
1 kOhm ±10 % (1 to 3 kOhm for sidetone)
unbalanced
Music Inputs:
Quantity
Rated level
Impedance
Circuitry type
2 (left channel, right channel)
1.4 Vrms nominal (850 mVrms to 2.4 Vrms)
11 kOhm ±10 %
unbalanced
Page 1-2
ENG-FORM: 800-0107.DOT
Oct 13, 2005
Amendment # 1
Oct 14, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
AA12S Series Compact Audio Controller Manual
Bidirectional Signals
ICS TIE Channel:
Quantity
Rated level
Impedance
Circuitry type
1
340 mVrms nominal (170 to 680 mVrms)
2 kOhm ±10 %
unbalanced
Output Signals
Phones:
Quantity
Rated level
Impedance
Circuitry type
4 (Pilot, Copilot, 2 Passengers)
>5.5 Vrms (>100 mW, RX, ICS and music)
>0.7 Vrms (TX sidetone, adjustable)
1.5 Vrms nominal (Pilot ISO mode)
>0.2 Vrms (Automatic failsafe mode)
300 Ohm ±10 %
transformer, unbalanced
Quantity
Rated level
Impedance
Circuitry type
4 (COM1, COM2, COM3 and PA)
250 mVrms ±10 %
150 Ohm nominal
direct throughline via relay
Keylines:
Quantity
Rated level
Circuitry type
Audio Performance
4 (COM1, COM2, COM3 and PA)
<1 A
grounded relay contact
Mics:
As per RTCA DO-170 Product Classification 1a except where noted.
* Manufacturers Specification
** Exceeds DO-170 requirement
Rated Output Power (each stereo channel)
Audio freq. Response:
Receive
Intercom
ICS Tie
Music
Distortion
≤3dB down from 350 - 6000 Hz
≤3dB down from 350 - 3000 Hz
≤3dB down from 350 - 3000 Hz
≤3dB down from 300 - 15000 Hz
(Music Bass control at mid setting)
≤10%, ≤3 % typical (350 to 6000 Hz)
Input - Input crosstalk
-37 dB max*
Input - Output crosstalk
-55 dB max
Input - Mic crosstalk
<200 µVrms*
Oct 13, 2005
100 mW min. into 300 Ω
Page 1-3
ENG-FORM: 800-0107.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
AA12S Series Compact Audio Controller Manual
SM69 Rev. 4.00
Audio noise
-60 dB max**
Output Regulation
≤3 dB variance (350 to 6000 Hz)
Audio Communication
Loud & Clear
ICS Volume controls
<35 dB range*, 40 dB nominal
Music Volume controls
<35 dB range*, 40 dB nominal
Receive Input impedance 1 kΩ ±10 %
1.3.2
Mic Input impedance
150 Ω ±10 %
Music Input impedance
11 kΩ ±10 %
ICS Tie Line
2 kΩ ±10 %
Physical Specifications
1.3.3
Width
4.95" (125.7 mm) max, behind panel
Depth
5.80" (147.3 mm) max, behind panel
Height
1.15" (29.2 mm) max
Weight
1.2 lb (0.50 kg) max
Mounting
Dzus rail, four fasteners, 5.366" horizontal
spacing, and 0.750" vertical spacing
Faceplate
Lighted panel is laser-engraved acrylic edge lit
with blue-white backlighting
Material/Finish
Brushed aluminum with chromate conversion
Connectors
One 25-pin female D-min connector with jackposts
One 44-pin male high-density D-min connector
with jackposts
Installation Kit
AA12S-IKC
Environmental Specifications
Temperature
-20 °C to +55 °C
Altitude
50,000 ft
Shock
6g/11ms, 20g/11ms
Safety of Flight requirements per RTCA DO-160D Environmental Conditions
DO-160D Env. Cat. [(A1)(D1)X]BXB[(SMB)(UF)]XXXXXXZBAXXXMXXXX
Page 1-4
Oct 13, 2005
ENG-FORM: 800-0107.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
1.3.4
AA12S Series Compact Audio Controller Manual
Unit Nomenclature
Variants of the AA12S series Compact Audio Controllers are identified as follows:
AA12S-001
Unassigned Options
1.3.4.1
Lighting Voltage
Unassigned Options
These portions of the designator may be assigned to future special options.
1.3.4.2
Lighting Voltage
This portion of the designator refers to the lighting voltage of the specific model.
001 = 28 Vdc lighting
004 = 14 Vdc lighting
End of section 1
Oct 13, 2005
Page 1-5
ENG-FORM: 800-0107.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
AA12S Series Compact Audio Controller Manual
Section 2 Installation
2.1
Introduction
Information in this section consists of: unpacking and inspection procedures, installation
procedures, post-installation checks, and installation drawings.
2.2
Unpacking and Inspection
Unpack the equipment carefully and locate the warranty card. Inspect the unit visually
for damage due to shipping and report all such claims immediately to the carrier
involved. Note that each unit should have the following:
- AA12S Series Compact Audio Controller
- Warranty Card
- Operator’s Manual
- Release certification
Verify that all items are present before proceeding and report any shortage immediately
to your supplier.
2.2.1
Warranty
Complete the warranty card information and send it to NAT when the installation is
complete. If you fail to complete the warranty card, the warranty will be activated on
date of shipment from NAT.
Note: An appropriately rated facility, e.g. Certified Aircraft Repair Station, must install
this equipment in accordance with applicable regulations. NAT Ltd’s warranty is
not valid unless the equipment is installed by an authorized NAT Dealer. Failure
to follow any of the installation instructions, or installation by a non-certified
individual or agency will void the warranty, and may result in a non-airworthy
installation.
2.3
Installation Procedures
2.3.1
Warnings
Do not bundle any lines from this unit with transmitter coax lines. Do not bundle any
audio or DC power lines from this unit with 400 Hz synchro wiring or AC power lines. Do
not position this unit or wiring from this unit next to any device with a strong alternating
magnetic field such as an inverter, or significant audio interference will result.
Oct 13, 2005
Page 2-1
ENG-FORM: 805-0106.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
AA12S Series Compact Audio Controller Manual
2.3.2
SM69 Rev. 4.00
Cautions
In all installations, use shielded cable exactly as shown and ground as indicated.
Significant ground loop and noise problems may result from not following these
guidelines.
The shielding and routing of the MIC and ICS TIE LINES used in the AA12S installation
is very critical and poor performance of the aircraft audio system will result if these
issues are not handled properly.
The operation of the VOX intercom can be severely degraded by the quality and type or
mix of microphones used in the aircraft. If one user has a very 'hot' microphone, it will
present more electrical signal to the VOX circuit and the VOX SQUELCH will have to be
set to quiet this microphone. The other microphones may not be able to generate
enough electrical energy to overcome this VOX SQUELCH setting, and will break up or
not be heard at all.
2.3.3
Notes
Audio performance can be impaired by the introduction of airframe electrical noise at
the headset jack locations. For best results, all headset jacks should be fully isolated
from the airframe.
2.3.4
Cabling and Wiring
All unshielded wire should be MIL-W-22759 or equivalent.
For shielded wire
applications, use Tefzel MIL-C-27500 shielded wire with solder sleeves (for shield
terminations) to make the most compact and easily terminated interconnect. Follow the
wiring diagrams in Section 2.6 as required.
Allow 3 inches from the end of the wire to the shield termination to allow the hood to be
easily installed. Note that the hood is a ‘clamshell’ hood, and is installed after the wiring
is complete.
All wiring should be at least 22 AWG, except power and ground lines, which should be
at least 20 AWG. Ensure that all ground connections are clean and well secured.
2.3.5
Post-Installation Checks
If any preset requires adjustment, be sure this is carried out before the aircraft leaves,
and that the unit and its mating connector are secured before departure. Make all
required log book entries, electrical load, weight and balance amendments and other
paperwork as required by your local regulatory agency.
Page 2-2
Oct 13, 2005
ENG-FORM: 805-0106.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
2.3.5.1
AA12S Series Compact Audio Controller Manual
Voltage/Resistance Checks
Check the following:
a)
P101 pin <1> for avionics buss voltage.
b)
P101 pin <16> for continuity to ground.
c)
P101 pins <9> <10> <11> and <12> for continuity to ground when the relevant
switch is closed. (Also check pins <13> and <14> if switches are installed in
these positions.)
d)
P301 pin <5> for avionics lighting bus voltage relative to ground (with lighting on).
e)
P301 pin <17> for continuity to ground.
2.3.5.2
Power On Checks
a)
Install the AA12S and power up the ship’s systems. Turn on the radios and
accessories required for the system.
b)
Check for correct radio audio and adjust for acceptable level.
c)
Run through all installed functions, and check the ICS and TX functions for all
users. Refer to Section 3 for specific operation details.
Note: Significantly different headsets may have different mic characteristics.
d)
If any preset requires adjustment, be sure this is carried out before the aircraft
leaves, and that the unit and its mating connector are secured before departure.
Make all required log book entries, electrical load, weight and balance
amendments and other paperwork as required by your local regulatory agency.
2.3.6
Adjustments
The internal adjustments that can be varied are located along the sides of the unit and
are accessed through necessary switches and trimpots.
Note: The unit is shipped 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.
2.3.6.1
ICS
BAL
R
ICS
BASS
Left Side Adjustments
MUSIC
MUTE
L
Oct 13, 2005
The adjustments found on the left side of the unit are:
ICS BAL R L, which controls the ICS Balance;
ICS BASS, which controls the ICS bass level;
and MUSIC MUTE, which controls the Music mute level.
Page 2-3
ENG-FORM: 805-0106.DOT
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AA12S Series Compact Audio Controller Manual
2.3.6.2
SM69 Rev. 4.00
Right Side Adjustments
RX
The adjustments found on the right side of the unit
BAL
are:
TX S/T, which controls the sidetone level;
R L
RX BAL R L, which controls the RX Balance;
RX VOL, which controls the RX volume level;
MUSIC BASS, which controls the Music Bass level;
and MUSIC BAL R L, which controls the Music balance.
RX
VOL
MUSIC MUSIC
BASS
BAL
R
TX
S/T
L
Upon satisfactory completion of all performance checks, make the required log
entries and complete the necessary Regulatory Agency paperwork before
releasing the aircraft for service.
2.4
Continued Airworthiness
Maintenance of the AA12S is ‘on condition’ only. Periodic maintenance of this product is
not required.
2.5
Accessories Required But Not Supplied
Installation kit p/n AA12S-IKC (crimp) is required to complete the installation. The kit
consists of one 44-Pin D-min Female Crimp Kit (NAT Part # D44SL-IKC) and one 25-Pin
D-min Male Crimp Kit (NAT Part # D25PL-IKC).
The D44SL-IKC consists of:
Quantity
Description
NAT Part #
1
44
1*
1*
1
D-min 44 Socket Housing
Mini D Crimp Socket
Jack Screw Set
Lock Clip Set
25 pin Connector Hood
20-20-044
20-26-703
20-27-002
20-27-004
20-29-026
The D25PL-IKC consists of:
Quantity
Description
NAT Part #
1
25
1*
1*
1
D-min 25 Pin Housing
MS Crimp Pin
Jack Screw Set
Lock Clip Set
25 Pin Connector Hood
20-11-025
20-26-891
20-27-002
20-27-004
20-29-026
* Use as required.
Page 2-4
Oct 13, 2005
ENG-FORM: 805-0106.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
2.6
AA12S Series Compact Audio Controller Manual
Installation Drawings
DRAWING
AA12S\001\403-0
AA12S\001\405-0
AA12S\001\905-0
AA12S\001\922-0
REV.
1.10
1.10
1.10
1.10
DESCRIPTION
AA12S Compact Audio Controller
AA12S Compact Audio Controller
AA12S Compact Audio Controller
AA12S Compact Audio Controller
TYPE
Interconnect
Connector Map
Faceplate
Mech. Installation
SERIAL #
All
All
All
All
Section 2 ends after these Drawings
Oct 13, 2005
Page 2-5
ENG-FORM: 805-0106.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
R
L
R
L
MUSIC MUSIC
BASS
BAL
MUSIC
MUTE
RX
VOL
ICS
BASS
RX
BAL
L
ICS
BAL
R
TX
S/T
SM69 Rev. 4.00
AA12S Series Compact Audio Controller Manual
Section 3 Operation
3.1
Introduction
Information in this section consists of the functional and operational procedures for the
AA12S Series Compact Audio Controllers.
The information in this manual is applicable to all models unless otherwise specified.
3.2
General Information
The AA12S is a compact Dzus-mounted audio controller with an integral 4-place stereo
voice-activated intercom. It provides intercom capabilities for the pilot, copilot and two
passengers (PAX). The AA12S accepts stereo music inputs from either portable or
fixed entertainment systems to produce high quality stereo headset output.
Radio functions include selectable transmit capability for pilot and copilot on 3 COM
radios and a PA. Receive audio selections include COM1, COM2, COM3, MKR, NAV,
ADF, and DME.
3.2.1
Features
All four mics have individual VOX gating. Each gate may also be activated with the
corresponding ICS keyline.
ICS muting is automatic during radio transmission.
The unit is supplied to suit a standard NAT bidirectional ICS audio TIE line for multi-unit
interface (configuration dependent). The crew and PAX are always connected except in
the case of Pilot ISO mode, when the pilot is disconnected from the ICS tie line.
3.2.2
Installation Adjustments
The following audio levels can be adjusted at the time of installation, or during service
by an approved dealer, using individual level trimpots.
•
Music Mute level
•
Sidetone level
•
ICS Bass level
•
ICS Balance
•
RX volume level
•
RX Balance
•
Music Bass level
•
Music Balance
Oct 13, 2005
ENG-FORM: 806-0106.DOT
Page 3-1
Amendment #1
Oct 14, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
AA12S Series Compact Audio Controller Manual
3.3
Operation Specifics
3.3.1
Radio Selection
VOX/TX Annunciator
3.3.1.1
RX Select Switches
SM69 Rev. 4.00
TX Select Switch
Receive
The AA12S is typically configured to select the RX audio from three transceivers and up
to four additional receivers.
The RX Select switches are white double-throw centre-off switches. Receiver audio can
be selected by setting the appropriate RX select switch to the down position.
Transceiver audio can either be selected by setting the appropriate RX select switch to
the up position, or as a function of the TX select switch. The transceiver that is selected
by the TX select switch is also automatically selected for receive. Receive/sidetone
audio for the selected COM is automatically provided.
When a switch is in the centre-off position, no transceiver/receiver audio is selected.
3.3.1.2
Transmit
The TX select switch is a 4-position rotary control that provides radio selection for up to
three transceivers and a PA. By selecting the desired transceiver and pressing the
external TX PTT switch, the AA12S is activated for transmit operation, connecting the
respective mic to the selected transceiver. The transceiver that is selected by the TX
select switch is also automatically selected for receive. The front panel annunciator will
illuminate green to indicate transmit operation (see section 3.1.3.)
TX selections are available only to the pilot and copilot. Activation of either TX PTT
input connects the user’s MIC to the selected COM, and activates the output PTT to the
selected COM. When PTT is pressed, all audio except the sidetone of the selected
COM and NAV inputs is removed from the headphone of the particular PTT user. The
sidetone of the active COM is provided from the COM radio.
The PA position provides PA mic audio and PA keyline to an external amplifier (e.g.
AA21, AA23, PA250) for use as either a Loudhailer or Passenger Address system.
A priority transmission feature allows the pilot to override the co-pilot.
Page 3-2
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Oct 13, 2005
Amendment #1
Oct 14, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
3.3.1.3
AA12S Series Compact Audio Controller Manual
VOX/TX Annunciator
The VOX/TX Annunciator is a bicolour LED that indicates the intercom status.
During VOX activity, the annunciator LED is illuminated red. If TX is keyed with no ICS
or sidetone, the annunciator LED is illuminated green. If TX is keyed with mic or
sidetone, the combination of red and green will cause the LED to appear amber.
Note: If the LED is still illuminated green after transmission is concluded, this indicates
a possible stuck mic.
3.3.2
Intercom
ICS VOL/VOX Squelch Control
VOX/TX Annunciator
The VOX and ICS VOL control is a fluted concentric knob, with the ICS volume on the
centre knob, and the VOX control on the outer knob.
3.3.2.1
VOX Control
The VOX control is used to set the level of audio required to activate the microphones.
The AA12S provides three modes of intercom operation, selected by the position of the
VOX control.
LIVE ICS
When the VOX control is positioned fully counter-clockwise (ccw), all mics
will be live, and any sound picked up by the microphone(s) will be
processed by the ICS system
KEYED ICS When the VOX control is positioned fully clockwise (cw), the intercom will
be in a keyed-only mode.
VOX ICS
When the VOX control is positioned between fully cw and fully ccw, the
intercom is in VOX mode. To establish the VOX threshold, rotate the
control ccw until the LED turns red, and then rotate the control cw until the
LED goes dark. Continue turning the control cw until the desired voice
sensitivity is set.
Oct 13, 2005
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Page 3-3
Amendment #1
Oct 14, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
AA12S Series Compact Audio Controller Manual
3.3.2.2
SM69 Rev. 4.00
ICS Volume Control
The ICS VOL control, which has a line to mark rotational position, is at minimum volume
when fully ccw. As the knob is rotated cw, the ICS volume for crew and PAX increases.
The ICS is muted during transmit operations.
3.3.3
PILOT ISO / NORM Modes
Pilot Isolate Switch
The PILOT ISO/NORM control is a red, two-position toggle switch that allows selection
of either NORM (Normal) or PILOT ISO (Pilot Isolate).
In NORM mode (default) everyone on the system can talk to each other, listen to music,
and hear all selected radio audio.
The PILOT ISO mode separates the pilot from the intercom network, allowing
confidential radio communications without interference from the copilot or passenger
intercom or music, while maintaining complete control of all the radio functions of the
audio panel. The copilot and passengers retain normal intercom and music functions.
Note: In PILOT ISO mode, the receive/sidetone levels may require adjustment at the
audio source.
3.3.4
Entertainment Audio
The AA12S accepts stereo music input from portable entertainment units, CD players or
other integrated on-board systems. The stereo output delivers music to stereo, or
standard monaural, general aviation headsets (installation dependent).
Music muting occurs during any radio or intercom activity.
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ENG-FORM: 806-0106.DOT
Oct 13, 2005
Amendment #1
Oct 14, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM69 Rev. 4.00
3.3.5
AA12S Series Compact Audio Controller Manual
Automatic Fail-safe
In the event of a power failure, automatic fail-safe operation will be activated. This
routes the pilot’s phones, mic audio, and mic PTT directly to the COM radio selected by
the position of the TX rotary selector switch, and selected audio inputs. Copilot and
passengers will have no ICS, music, or receive functions.
In the unlikely event of an AA12S circuit failure that results in a communication failure,
the automatic fail-safe mode can be enabled by pulling the AA12S circuit breaker.
Note: In Automatic Fail-Safe mode, the receive/sidetone levels may require adjustment
at the audio source.
The pilot should confirm that all aspects of Automatic Fail-Safe operation are
working before accepting the aircraft into service.
End of section 3
Oct 13, 2005
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ENG-FORM: 806-0106.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.