Northern Airborne Technology AA82 User Manual

Installation and Operation Manual

AA82 InterMUSIC™

Stereo Intercom System

SM09-1

ISSUE 4.11

Northern Airborne Technology Ltd.

1925 Kirschner Road

Kelowna, BC, Canada.

Telephone [phone]

Facsimile [phone]

Issued on the authority of Northern Airborne Technology Ltd.

Copyright 2004

V1Y 4N7

AA82 InterMUSIC™ Stereo Intercom System

SM09-1 Installation and Operation Manual

Prepared By: Checked By: Approved By:

The status of this installation and operation manual is controlled by issue shown on the title page. The
status of each section is controlled by revision shown in the footer of each page. All revisions affecting
sections of this manual have been incorporated into the latest issue.

ISSUE/REVISION RECORD

Manual Issue

Number

Section

Revision Number

Revision Description Issue Date

4.11 Section 1 Rev: 1.00
Section 2 Rev: 1.00
Section 3 Rev: 1.00

Updated Installation Kit Information.

Update to current templates.

Aug 29, 2008

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AA82 InterMUSIC™ Stereo Intercom System

SM09-1 Installation and Operation Manual

Table of Contents

Section Title Page

1. Description

1.1 Introduction 1-1

1.2 Product Description 1-1

1.3 Design Features 1-1

1.4 Specifications 1-2

1.4.1 Electrical Specifications 1-2

1.4.2 Physical Specifications 1-3

1.4.3 Environmental Specifications 1-3

2. Installation

2.1 Introduction 2-1

2.2 Unpacking and Inspection 2-1

2.2.1 Warranty 2-1

2.3 Continued Airworthiness 2-1

2.4 Installation Procedures 2-2

2.4.1 Warnings 2-2

2.4.2 Cautions 2-2

2.4.3 Cabling and Wiring 2-2

2.4.4 Mounting 2-3

2.4.5 Post Installation Checks 2-3

2.5 Adjustments and Connections 2-3

2.5.1 Radio Settings 2-4

2.5.2 Setting Up Music and Muting 2-4

2.5.3 Setting Balance and Bass Potentiometers 2-4

2.5.4 Other ICS Functions 2-5

2.5.5 Music Selection (AA82-060 only) 2-5

2.5.6 Final Check 2-5

2.6 Accessories Required 2-6

2.7 Installation Drawings 2-7

3. Operation

3.1 Introduction 3-1

3.2 General Information 3-1

3.3 Controls and Indicators 3-1

3.3.1 Stereo & Intercom Special Features 3-2

3.3.2 Logic Explanation 3-2

3.3.3 Tie/Split Operation 3-2

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AA82 InterMUSIC™ Stereo Intercom System

SM09-1 Installation and Operation Manual

Section 1 Description

1.1 Introduction

Information in this section consists of product description, design features and specifications for the AA82
InterMUSIC™ Stereo Intercom System. All derivative product information shall be contained in the
applicable manual supplement, which may be obtained from NAT as required.

Review all notes, warnings and cautions.

1.2 Product Description

The AA82 InterMusic™ Stereo Intercom System is a system for passenger entertainment and
communications. The system is available in two models, the AA82-001 and AA82-060. The AA82-001 is
compatible with AA80 intercoms and allows four stereo positions. The AA82-060 is compatible with AA83
intercoms and allows six stereo positions. Each is linked via the ICS Tie Line to the crew audio system.

The AA82 InterMUSIC™ Stereo Intercom offers the passengers full control of their intercom and
entertainment functions. The front panel controls permit adjustment of Intercom level, VOX threshold and
Music level. Internal adjustments set Receive lev e l, Receive balance, ICS balance, ICS bass, Music
muting and Music balance. These controls allow unique features such as making the intercom audio
appear to be coming from the left and receive audio coming from the right, which is helpful in relating the
audio to the source. The stereo audio is muted during intercom operation or when receive audio is
detected, permitting greater intelligibility of in coming transmissions. A front panel annunciator allows
easy visual setting of the VOX threshold and also indicates RX signal reception.

1.3 Design Features

The AA82 uses surface mount technology and provides true stereo music audio to the headset.
The InterMUSIC™ system employs NAT's unique audio processing, which red uces noise and tailors the

frequency response to produce clean, crisp intercom audio.
High output power and low distortion results in better on-board communication and greatly reduces noise

fatigue.
Employing highly integrated stereo audio processors, component numbers were substantially reduced

and product reliability is increased.
With the reduction of component size, more features were incorporated (Adjustable music muting by

intercom and receive audio, bass control of intercom and stereo audio).
Designed into the smallest possible chassis, it allows mounting in the remotest locations (usually close to

the passengers).
The AA82's ICS Tie Line is fully compatible with existing NAT products, making it possible to chain

multiple systems together (3 units max).
The unit has overvoltage and reverse voltage protection to insure operability in severe aircraft

environments.

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1.4 Specifications

1.4.1 Electrical Specifications

Input Power +11 to +32 Vdc
Supply Current 385 mA max. (full output power)
Headset Power 400 mW per channel (total power)

100 mW typical into each headset element (300 Ω/side)
4 headsets (AA82-001)
6 headsets (AA82-060)

Lighting 160 mA at 28 Vdc
600 mA at 5 Vdc

Modes of Operation Voice track trigger circuit
Adjustable threshold on panel
‘Live’ or ‘Hot’ mic by rotating VOX control counterclockwise

Indicators Receive monitor (Green LED)
VOX ICS triggered (Amber LED)

Front Panel Controls ICS Volume
Music Level
VOX Threshold

Internal Side Panel Controls RX Volume
RX Balance
ICS Balance
Music Balance

Inputs (AA82-001) 4 microphone ‘carbon equivalent’, 250 mVrms for full output,

150 Ω input impedance
4 ICS keylines (active ground) for all users
2 music inputs compatible (left & right), configurable for portable

CD/cassette only, phones compatible (3 Vp-p)
Inputs (AA82-060) 6 microphone ‘carbon equivalent’, 250 mVrms for full output,

150 Ω input impedance
6 ICS keylines (active ground) for all users
2 music inputs compatible (left & right), configurable for either

portable CD/cassette, phones compatible (3 Vp-p) or CD

changer Line Out compatible (100-500 mV @ 10 kΩ)
Inputs (all models) 1 radio input, 2.5 Vrms for full output, 1 kΩ input impe dance

1 bi-directional ICS Tie Line, 1 Vp-p for full output, 2 kΩ input

impedance

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AA82 InterMUSIC™ Stereo Intercom System

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Outputs (AA82-001) 4 aircraft stereo headsets (300 Ω/side)
Note: Not designed for 8 Ω headsets.

Outputs (AA82-060) 6 aircraft stereo headsets (300 Ω/side)
Note: Not designed for 8 Ω headsets.

Logic ICS and RX audio both mute the music channel
No emergency or transmit functions

1.4.2 Physical Specifications

Height 1.30" (33.0 mm)
Depth 5.60" (142.2 mm) excluding front panel controls
Width 2.60" (66.0 mm)
Weight 0.6 lbs (283.5 g) excluding external hardware
Mounting Horizontal or vertical with reversible faceplate for through-panel

mounting

1.4.3 Environmental Specifications

Temperature -40 to +70°C (operating)

-55 to +85°C (storage)
Altitude 25,000 feet max.
Humidity 95% Non-condensing

Section 1 ends

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AA82 InterMUSIC™ Stereo Intercom System

SM09-1 Installation and Operation Manual

Section 2 Installation

2.1 Introduction

Information in this section consists of unpacking and inspection procedures, installation procedure s, po st­installation checks and installation drawings for the AA82 InterMUSIC™ Stereo Intercom System.

Review all notes, warnings and cautions.

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. Check that all items listed below
are present before proceeding and report any shortage immediately to your supplier:

- Warranty Card

- Operators Manual

- Certificate of Conformity or Release Certification

- Installation kit with faceplate (crimp type connector)

2.2.1 Warranty

All Northern Airborne Technology Ltd. products are warranted for 2 years from date of installation by an
authorized NAT dealer, to be free of defects in workmanship or performance. This warranty covers all
materials and labour, but is exclusive of any transport to deliver the defective unit to and from NAT or its
designated warranty repair center, or any labour to remove or re-install the defective unit in the aircraft.
Contact NAT for any questions regarding this warranty, its applicability to your units and/or for return
authorization. NAT is the final arbitrator concerning warranty administration. Units which have been
physically damaged, burned, immersed in water or otherwise abused beyond the scope of normal use will
not be considered for warranty. WARRANTY IS VOID UNLESS THE PRODUCT IS INSTALLED BY AN
AUTHORIZED NAT DEALER. Product for which a warranty card is not returned shall be warranted from
date of manufacture.

2.3 Continued Airworthiness

Maintenance of the AA82 InterMUSIC™ Stereo Intercom System is ‘on condition’ only. Periodic
maintenance of this product is not required.

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2.4 Installation Procedures

2.4.1 Warnings

High volume settings can cause hearing damage.

Set the headset volume control to the minimum volume setting prior to

conducting tests, and slowly increase the headset volume to a

comfortable listening level.

2.4.2 Cautions

DO NOT use mono aircraft headsets in this system. Mono aircraft headsets will

short out one side of the AA82 power amplifier when installed in the stereo jacks.

This may result in eventual unit failure. Use only stereo headsets with this system.

WARNING:

CAUTION:

2.4.3 Cabling and Wiring

All wire shall be selected in accordance with the original aircraft manufacturer's Maintenance Instructions
or AC43.13-1B Change 1, Paragraphs 11-76 through 11-78. Unshielded wire types shall qualify to
MIL-W-22759 as specified in AC43.13-1B Change 1, Paragraphs 11-85, 11-86, and listed in Table 11-11.
For shielded wire applications, use Tefzel MIL-C-27500 shielded wire with solde r sleeve s (fo r shield
terminations) to make the most compact and easily terminated interconnect. Follow the connector map in
Section 2.7 as required.

Allow 3" from the end of the shielded wiring to the shield termination to allow the connector hood to be
easily installed. Reference the interconnect drawing in Section 2.7 for shield termination details. Note that
the hood is a "clamshell" hood, and is installed after the wiring is complete. Aircraft harnessing shall
permit the unit to be removed from the panel for easy access to all side adjustments. Do NOT mount the
unit until all adjustments have been performed.

Maintain wire segregation and route wiring in accordance with the original aircraft manufacturers
Maintenance Instructions.

Unless otherwise noted, all wiring shall be a minimum of 24 AWG, except power and ground lines, which
shall be a minimum of 22 AWG. Reference the Interconnect drawing for additional specifications. Check
that the ground connection is clean and well secured, and that it shares no path with any electrically noisy
aircraft accessories such as blowers, turn and bank instruments or similar loads. Power to this unit must
be supplied from a separate circuit breaker or fuse (fast blow), and not attached to any other circuit
breaker without additional protection. Verify that the selected circuit breaker size and wire gauge are
adequate for the installation using the techniques specified in AC43.13-1B Change 1, Paragraphs 11-47
through 11-51 and 11-66 through 11-69.

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2.4.4 Mounting

The AA82 InterMUSIC™ Stereo Intercom can be mounted in either a vertical or horizontal orientation.
Place the adhesive backed drill template in an appropriate place on the instrument panel and drill through
the indicated locations. The mounting nuts on the faceplate controls should not be removed at any time.
The clearance holes for the nuts should be 3/8" to allow them to fit through the instrument panel. The unit
is secured by three black Phillips screws, which require 5/32" hole s.

Notes: 1) The clock mount faceplate used with the AA80 Series is not supplied.

2) Perform all functional tests and adjustments prior to mounting. Secure the unit to the panel
prior to flight.

2.4.5 Post Installation Checks

2.4.5.1 Voltage/Resistance Checks

Do not attach the AA82-xxx until the following conditions are met.

Check the following for the AA82-001:

a) Check pin 1 for +11 to +32 Vdc relative to ground.
b) Check pin 14 for continuity to ground (less than 0.5Ω).

Check the following for the AA82-060:

a) Check pin 1 for +11 to +32 Vdc relative to ground.
b) Check pin 16 for continuity to ground (less than 0.5Ω).

2.4.5.2 Power On Checks

Power up the aircraft’s systems and confirm normal operation of all functions of the AA82-xxx. Reference
Section 3 for specific operational details.

a) Check that headsets are installed correctly.
b) To verify proper operation, all functions and levels shall be checked in-flight.
c) Check preset adjustments are completed before aircraft departure.

Upon satisfactory completion of all performance checks, make all required log book entries, electrical
load, weight and balance amendments and other documentation as required by your local regulatory
agency before releasing the aircraft for service.

2.5 Adjustments and Connections

All AA95/AMS4X Audio Controllers used with the AA82 must have the ICS Tie Line and Gain
Modifications installed. This applies to units with a serial number less than 1918.

The AA82-xxx has internal trimpot adjustments accessible through holes in the right and left sides of the
unit. The AA82-060 also has internal jumper settings for music input types. Reference Section 2.5.5 for
jumper settings.

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2.5.1 Radio Settings

To achieve correct radio volume settings, check that the headset radio level is acceptable. This
adjustment should be made with the radio volume set to about 50%. Adjust the headset volume control
(if it exists) for something less than full volume, such as 75% (full output on active headsets will give the
worst over-all signal to noise ratio, as it will increase the low level noise floor). Adjust the RX VOL on the
side of the AA82 to a preferred level.

Check that the music is muting at this stage when a radio signal is received. If not, the radio itself set too
low and must be increased at the radio to properly activate the internal muting circuit in the AA82. Once
the radio settings are satisfactory, perform all other adjustments. The RX VOL trimpot sets only the radio
level heard during normal operation and has no effect on any other function, including muting.

2.5.2 Setting Up Muting and Music

Rotate the front panel VOX potentiometer until the VOX indicator is off. The music audio can now be
heard. Adjust the music to a comfortable level with the front panel potentiometer. If the music is louder in
one ear than the other, the side panel MUSIC BAL control may need adjusting, although this could be a
problem with your music source, as this adjustment should be correct from the factory.

With the front panel VOX potentiometer turned fully counter-clockwise (LIVE ICS, the indicator should be
ON), adjust the MUSIC MUTE trimpot to the desired level of music audio in the background. This is the
level the music will default to whenever it is muted and can range from OFF to only slightly muted as
preferred.

2.5.3 Setting Balance and Bass Potentiometers

With the VOX control still in the LIVE ICS position, talk back and forth on the intercom to determine the
voice quality. If more bass is desired, the ICS BASS potentiometer may be adjusted for the preferred
tone. Check that this adjustment is compatible with the headsets and that it does not increase distortion. If
the ICS audio seems distorted, reduce the ICS BASS potentiometer for best results. Some aircraft
headsets do not have very good internal microphone amplifiers and achieve "noise reduction" by shunting
the microphone with a large capacitor to reduce high frequency noise. This may make the voice very bass
heavy and muffled. Best results were obtained in NAT testing with the following headsets:

Bose (may require re-wiring of plug for stereo)
David Clark (may require modification for stereo)

Most aircraft headsets do not do a good job of reproducing wide bandwidth music information, which
seriously compromises the performance of the AA82. NAT will test any headset for system compatibility if
the unit is supplied for evaluation with the AA82.

If you wish the ICS audio to come from a particular location (left to right), adjust the ICS BAL
potentiometer for the desired position.

Note: If you have not controlled the Left/Right headset jack wiring, it may appear to change locations

between different users.

Set the location to suit your preference, listen to an incoming radio transmission and position it (ideally) in
the opposite location with the RX BAL trimpot. The best setup should give some perceived difference in

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location for these two sources (radio & ICS), as it will improve recognition of who is speaking in the
system.

2.5.4 Other ICS Functions

Check all installed functions and check the ICS function for all users. The VOX potentiometer on the front
controls all passengers. Adjust as needed for the best performance.

Note: Significantly different headsets may have different microphone characteristics, which affect VOX

squelch settings.

Note: The David Clark M-7 microphone is more active than M-4 or M-1 micro phones and may

aggravate headset imbalance if used in a mixed system.

To test KEYED ICS operation of the AA82-060, be sure the VOX potentiometer is set fully clockwise and
all ICS audio is shut off. Keying the ICS switches should activate the specific microphone involved.

Note: Each microphone is individually gated in the AA82-060 and only the microphone involved with a

key signal is activated.

The front panel indicator should illuminate orange when there is activity on the intercom.

2.5.5 Music Selection (AA82-060 only)

The cover of the unit must be removed in order to access jumper locations. Reference Section 6 for
Exploded View AA82\060\904-0 and Component Locator AA82\060\924-0 drawings.

Note: The AA82 is a static sensitive device. Use proper ESD handling procedures when the cover is

removed.

To gain access to the jumpers, remove the cover from the AA82. Remove the top PCB by removing the
three pan head screws and carefully lifting it straight up. When reassembling the unit check that the pins
and connector are aligned properly before screwing the PCB down.

The two types of music inputs are configured by the position of jumpers JP101 and JP102, located on the
main PCB near the access hole for Q101. Music input type is determined as shown in Table 1:

Music Input Type Jumper Positions

Low Z/Portable cassette/CD compatible JP101 and JP102 Installed

High Z/CD changer compatible JP101 and JP102 Removed

Table 1

Music Input Type and Jumper Position

2.5.6 Final Check

Before leaving the aircraft, check that the mating connector is securely fastened to the AA82 and the unit
is securely fastened to the aircraft panel.

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2.6 Accessories Required

Installation kit p/n AA82-001-IKC (25 pin D-min Female Crimp) is required to complete the inst allation.
The kit includes NAT Part No. D25SL-IKC.

AA82-001-IKC consists of:

Quantity Description NAT Part No.

1 D-min 25 Socket Housing 20-21-025
25 MS Crimp Socket 20-26-901
1* Jack Screw Set 20-27-002
1* Lock Clip Set 20-27-004
1 25 Pin Connector Hood 20-29-026
3 5/8" 6-32 Black Pan Head Screw 25-11-427
2 Fluted 1/8" Knob 40-18-002
1 Fluted 1/8" Music Knob 40-18-MUS2
1 Hole Overlay 43-10-083
1 Rectangular Faceplate 50-04-821
* Use as required.

Installation kit p/n AA82-060-IKC (44 pin D-min Female Crimp) is required to complete the inst allation.
The kit includes NAT Part No. D44SL-IKC.

AA82-060-IKC consists of:

Quantity Description NAT Part No.

1 D-min 44 Socket Housing 20-20-044
44 Mini D Crimp Socket 20-26-703
1* Jack Screw Set 20-27-002
1* Lock Clip Set 20-27-004
1 25 Pin Connector Hood 20-29-026
3 5/8" 6-32 Black Pan Head Screw 25-11-427
1 Fluted 1/8" ICS Knob 40-18-ICS2
1 Fluted 1/8" Music Knob 40-18-MUS2
1 Fluted 1/8" VOX Knob 40-18-VOX2
1 Hole Overlay 43-10-080
1 Rectangular Faceplate 50-04-821
* Use as required.

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2.7 Installation Drawings

Use of the "#" symbol in the REV. column indicates that the document is listed elsewhere in the manual.
Refer to the applicable NAT Part No. to locate the referenced document.

DOCUMENT REV. DESCRIPTION TYPE SERIAL NO.
AA82-001

AA82\001\302-0 1.02 InterMUSIC Stereo Intercom Block Diagram All
AA82\001\403-0 1.01 InterMUSIC Stereo Intercom Interconnect All
AA82\001\405-0 1.01 InterMUSIC Stereo Intercom Connector Map All
AA82\001\921-0 1.00 InterMUSIC Stereo Intercom Mounting Plate All

AA82-060

AA82\060\302-0 1.01 InterMUSIC Stereo Intercom Block Diagram All
AA82\060\403-0 1.20 InterMUSIC Stereo Intercom Interconnect 1338 to 1477
AA82\060\403-0 1.31 InterMUSIC Stereo Intercom Interconnect 1478 and up
AA82\060\405-0 1.02 InterMUSIC Stereo Intercom Connector Map All
AA82\001\921-0 # InterMUSIC Stereo Intercom Mounting Plate

Section 2 ends following the above documents

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Confidential and Proprietary to NAT

Confidential and Proprietary to NAT

Confidential and Proprietary to NAT

A

AA82 InterMUSIC™ Stereo Intercom System

SM09-1 Installation and Operation Manual

Section 3 Operation

3.1 Introduction

Information in this section consists of functional and operational procedures for the AA82 InterMUSIC™
Stereo Intercom System.

3.2 General Information

The AA82 is available in two models, the AA82-001 and AA82-060. Both are designed for passenger
entertainment and communications. The AA82-001 is compatible with AA80 series intercom and allows
four stereo positions. The AA82-060 is compatible with AA83 series intercoms and allows six stere o
positions. Each is linked via the bi-directional ICS Tie Line to the crew audio system.

3.3 Controls and Indicators

The front panel controls shown in Figure 1 permit user adjustment of frequently needed signals, such as
Intercom Audio Level (ICS Volume), Microphone VOX Threshold (VOX Squelch) and Music Level
(Musical Note).

ICS Volume

Music Volume

Figure 1: Front Panel Controls

Internal adjustments set default values for Receive Audio Level, Receive Balance, ICS Balance, ICS
Bass, Music Muting and Music Balance. These extensive controls allow some u nique features, such as
making the intercom and radio sources appear from distinct listening space positions to aid in recognition.

Music Muting allows the dynamic range of the music muting function to be set to suit individual
preferences and Bass adjustments allow tailoring to the exact characteristics of the headsets chosen.
Music muting occurs in a smooth, fast attack/slow return sequence, for maximum comfort and clarity of
communication in all modes.

nnunciator

VOX Squelch

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3.3.1 Stereo & Intercom Special Features

The stereo music audio is muted during intercom operation and when radio receive audio is detected,
permitting greater intelligibility of incoming transmissions. The AA82 Muting adjustment ranges from
complete music muting to gentle background music on command, with a fast attack and slow level return
for optimum user comfort. Each microphone is individually gated for the best possible noise performance
during VOX operation. A front panel annunciator allows easy visual setting of the VOX threshold and also
indicates radio signal reception.

3.3.2 Logic Explanation

When ICS or RX functions are active, any music will be muted quickly as shown in Table 1. The music will
slowly return when transmission is completed. The degree of muting is set at the time of installation. The
relative volume of the music can be changed from the front panel by adjusting the music volume knob
marked with a musical note.

Active: Function being used
Muted: Functions that are overridden by the active condition
Idle: Functions that are not active, but still available for use

Music ICS RX

Active Idle Idle
Muted Active Idle
Muted Idle Active
Muted Active Active

Table 1

Music Muting

3.3.3 Tie/Split Operation

The crew audio system that the AA82 is connected to may have a Tie/Split mode of operation. The crew's
Tie/Split switch connects or disconnects the ICS Tie Line from the passengers' intercom system. Intercom
between the passengers is maintained, but they are cut off from the crew ICS and radio audio. Many
different circuit combinations can be set up depending on what device is hooked to the Tie Line.

Section 3 ends

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