Nat AA21-400 User manual

CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
SM34
AA21-400
Cabin PA System
INSTALLATION AND OPERATION MANUAL
REV. 4.00 November 10, 2003
Northern Airborne Technology Ltd.
1925 Kirschner Road
Kelowna BC, Canada
V1Y 4N7
Telephone [phone]
Facsimile [phone]
Copyright 2003 by Northern Airborne Technology
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SM34 Rev. 4.00 AA21-400 Cabin PA System Manual
Nov 10, 2003 Page ii
ENG-FORM: 820-0109.DOT Amendment #2 May 24, 2006
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
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
Number Amendment Date Section(s) Changed Date Entered
Entered By
1 Jan 18\05 2
2 May 24\06 Pg iii, 1
3 Apr 21\09 2
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Performed at factory
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INSTALL_OPS
MANUAL AMENDMENT
Manual: SM34 (AA21-400) Amendment #: 3
Document # SM34\Install_Ops\809-0003 Amendment Date: Apr 21, 2009
Amendment #3 Apr 21, 2009 Page 1
ENG-FORM: 809-0109.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
The purpose of this amendment is to add the latest drawings to the manual.
Amendment Instructions:
1 Remove Pages Replace With Pages
2-5 Rev 4.00 Amendment 1 2-5 Rev 4.00 Amendment #3
2 Remove Drawings (Section 2) Replace or add Drawings (Section 2)
AA21\400\403-0 Rev 1.00 AA21\400\403-0 Rev 1.01
AA21\400\905-0 Rev 1.00 AA21\400\905-0 Rev 1.10
3 Update the Amendment Record sheet at the front of the manual.
4 Insert this page into the manual after the Amendment Record sheet (page ii).
Manual Amendment ends after the following amended pages
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INSTALL_OPS
MANUAL AMENDMENT
Manual: SM34 (AA21-400) Amendment #: 2
Document # SM34\Install_Ops\809-0002 Amendment Date: May 24, 2006
Amendment #2 May 24, 2006 Page 1
ENG-FORM: 809-0109.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
The purpose of this amendment is to correct the numbering sequence and add section
1.5 Accessories Required But Not Supplied to the table of contents.
Amendment Instructions:
1 Remove Pages Replace With Pages
Title Section Page iii Rev 4.00 Title Section Page iii Rev 4.00 Amendment #2
1-3 and 1-4 Rev 4.00 1-3 and 1-4 Rev 4.00 Amendment #2
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
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INSTALL_OPS
MANUAL AMENDMENT
Manual: SM34 (AA21-400) Amendment #: 1
Document # SM34\Install_Ops\809-0001 Amendment Date: Jan 18, 2005
Amendment #1 Jan 18, 2005 Page 1
ENG-FORM: 809-0109.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
The purpose of this amendment is to add the Environmental Qualification Form (521-0)
to section 2.5 and to update the section 2.3.4 Cable Wiring statement paragraph 1.
Amendment Instructions:
1 Remove Pages Replace With Pages
2-1, 2-2 and 2-5 Rev 4.00 2-1, 2-2 and 2-5 Rev 4.00 Amendment #1
2 Remove Drawings/Documents (Section 2) Replace or add Drawings/Documents (Section 2)
- AA21\400\521-0 Rev 1.20
Note: Ensure that all drawings are inserted in the order shown on the latest drawing lists.
3 Update the Amendment Record sheet at the front of the manual.
4 Insert this page into the manual after the Amendment Record sheet (page ii).
Manual Amendment ends after the following amended pages
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SM34 Rev. 4.00 AA21-400 Cabin PA System Manual
Nov 10, 2003 Page iii
ENG-FORM: 820-0109.DOT Amendment #2 May 24, 2006
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
Table of Contents
Section Title Page
1.0 Description
1.1 Introduction 1-1
1.2 Purpose of Equipment 1-1
1.3 Features 1-1
1.4 Specifications 1-2
1.4.1 Electrical Specifications 1-2
1.4.2 Physical Specifications 1-4
1.4.3 Environmental Specifications 1-4
1.5 Accessories Required But Not Supplied 1-5
2.0 Installation
2.1 Introduction 2-1
2.2 Unpacking and Inspection 2-1
2.3 Installation Procedures 2-1
2.3.1 Note to Installers 2-1
2.3.2 Warnings 2-1
2.3.3 Cautions 2-2
2.3.4 Cabling and Wiring 2-2
2.3.5 Post-Installation Checks 2-2
2.3.6 Adjustments 2-4
2.4 Continued Airworthiness 2-5
2.5 Installation Drawings 2-5
3.0 Operation
3.1 Introduction 3-1
3.2 Operation Specifics 3-1
3.3 Techniques of Voice Transmission 3-1
3.4 Basic operation 3-1
3.4.1 Power Up 3-1
3.4.2 Input Function Selection 3-2
3.4.3 Volume Control 3-2
3.4.4 Mode switches 3-3
3.4.5 Remote Power Switch 3-3
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SM34 Rev. 4.00 AA21-400 Cabin PA System Manual
Section 1.0 Description
1.1 Introduction
This manual contains information on the AA21-400 Cabin PA System.
Information in this section consists of purpose of equipment, features and specifications.
1.2 Purpose of Equipment
The AA21-400 Cabin PA control unit is designed to provide centralized control for an
aircraft’s internal and external PA systems. The design is contained in one panel-
mounted unit, with an illuminated faceplate. All audio and keylines are interfaced to
existing aircraft audio systems. Front panel switches provide selection of the various
operational modes of the AA21 and a potentiometer provides output volume control.
1.3 Features
The AA21-400 provides selection and control of internal and/or external PA system(s)
installed in an aircraft. The integrated 25 W speaker driver circuit is designed to drive
one 8 Ωspeaker arrangement for internal paging. The AA21-400 also provides a low-
level audio signal output that drives the input on a remote mounted power amplifier. The
output is designed to drive the NAT PA110/220 or PA250/700 series amplifiers. The
AA21-400 provides generation of wail and yelp siren audio on the low level output when
selected on the front panel.
A ‘+3 dB’ function allows the output level of the system to be varied by 3 dB. When the
input control line is grounded, the output is reduced by approximately 3 dB, and
removing the ground returns the system to full output.
Thermal protection is designed into the intermediate and final stage amplifiers to protect
the unit during very hot or extended high power operating conditions.
Four front panel switches provide selection of the various operational modes of the
AA21-400 as described in Section 3 of this manual (Operation).
Nov 10, 2003 Page 1-1
ENG-FORM: 800-0106.DOT Amendment #2 May 24, 2006
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AA21-400 Cabin PA System Manual SM34 Rev. 4.00
1.4 Specifications
1.4.1 Electrical Specifications
Power Supply Linear DC (with reverse & over voltage protection):
Normal: +27.5 Vdc nominal.
+22.0 Vdc minimum.
+30.3 Vdc maximum.
+18.0 Vdc emergency.
Input Current: 2.3 A max. full speaker power (35 W) @ +27.5 Vdc.
2.9 A max (35 W) with 0.40 A load on Switched
Power Output.
0.40 A idle @ +27.5 Vdc.
Backlighting: 150 mA max @ +27.5 Vdc.
Input Signals
Microphone: 150 Ohm amplified dynamic.
250 mVrms rated input level.
ALC Automatic level controlled for maximum intelligibility
without distortion starts @ 130 mVrms.
Impedance 130 Ohm ±10%.
Music: Only one of Radio (Receive) or CD may be enabled at
a time.
Radio (Receive) 2.5 Vrms into 1k Ω±10%.
CD 1.0 Vrms into 11k Ω±10%.
PA key: Active low. Max. current source 15 mA.
+3dB key: Active open, isolated through optical relay. Max.
current source 13 mA. Reduces all audio, except
sidetone, by 3 dB when grounded. The output will be
reduced 2 to 3 dB if operating above 25 W on speaker
output, or above 6.5 Vrms on PA output.
Input to Input Crosstalk: ≤-40 dB from rated output.
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SM34 Rev. 4.00 AA21-400 Cabin PA System Manual
Output Signals
Speaker: Impedance and short circuit protected.
≤10% THD 20 W single tone into 8 Ω@ 50% duty cycle. Continuous.
20 W voice/music into 8 Ω@ 100% duty cycle. Continuous.
Note: Distortion is ≤3% THD at 10% of continuous
output power rating.
> 10% THD 35 W max. into 8 Ωwith 2.5 Vrms into Radio (Receive) input.
Non-continuous (short term).
Audio bandwidth: Mic input: ≤3 dB roll-off from 350 Hz to 3 kHz
Radio (Receive)/CD input: ≤3 dB roll-off from 350 Hz to 6 kHz
PA: Selectable by internal jumper for either
PA110/220 (6.5 Vrms ±10% into 600 Ω) or
PA250/700 (0.5 Vrms ±10% into 600 Ω) for rated output.
Distortion: ≤3% THD at rated output.
Audio bandwidth: Mic input: ≤3 dB roll-off from 350 Hz to 3 kHz
Radio (Receive)/CD input: ≤3 dB roll-off from 350 Hz to 6 kHz
Siren: Only available on PA output (735 to 1620 Hz). Yelp
and wail modes with adjustable rates. Siren level
control provided for yelp/wail by one internal trimpot.
Sidetone: Adjustable 0-100 mW into 600 Ωwith ≤10% THD
Audio bandwidth: ≤3 dB roll-off from 350 Hz to 3 kHz
Input to Output ≤-50 dB from rated output.
Crosstalk:
Audio Noise Level: ≤-50 dB from rated output.
(without signal)
Switched Power: +27.5 Vdc @ 0.40 Amps max. Over current protected.
Temperature Sensor The unit contains a temperature sensor IC which
when triggered reduces the input signals by 3 dB.
The IC threshold is set to approximately 130°C.
Annunciator Power On (illuminates green when active)
Nov 10, 2003 Page 1-3
ENG-FORM: 800-0106.DOT Amendment #2 May 24, 2006
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AA21-400 Cabin PA System Manual SM34 Rev. 4.00
1.4.2 Physical Specifications
Height 1.11 ±0.03” (28.1 ±0.8 mm)
Depth 6.53 ±0.03” (165.9 ±0.8 mm) behind panel (including
connector).
Width 4.96 ±0.03” (126.0 ±0.8 mm) behind panel.
5.75 ±0.03” (146.1 ±0.8 mm) in front of panel.
Weight 1.40 ±0.07 lbs. (0.64 ±0.03 kg)
Mounting Std. Dzus Mounting (4 fasteners)
Faceplate Engraved acrylic edge lit panel, with 28 Vdc backlighting.
Material/Finish Chassis & cover: 5052-H32 brushed aluminum with
chromate conversion finish.
Heat sinks: de-burred 6063-T6 aluminum with chromate
conversion finish.
Connector Male filtered 25 pin D-subminiature with Positronics
V5 locking tabs.
1.4.3 Environmental Specifications
Operating Temp -30°C to +55°C
Survival Temp -55°C to +85°C
Humidity > 95%
Altitude 25,000 ft.
DO-160D Env. Cat. B4-BAB[(SBM)(UF)]XXXXXXZBABB[TTX]MXXXX
TSO Compliance TSO-C50c, RTCA DO170 Class II
(Applicable to units Serial # 1200 and up)
Page 1-4 Nov 10, 2003
ENG-FORM: 800-0106.DOT Amendment #2 May 24, 2006
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SM34 Rev. 4.00 AA21-400 Cabin PA System Manual
1.5 Accessories Required But Not Supplied
Installation kit p/n AA21-400-IKC (crimp) or AA21-400-IKS (solder) is required to
complete the installation. They consist of the following:
AA21-400-IKC (crimp) NAT Part #:D25SV-IKC
Quantity Description NAT Part #
1 D-min 25 Socket housing 20-21-025
25 MS Crimp Socket 20-26-901
1 25 Pin JVL Hood/Locklever 20-29-250
AA21-400-IKS (solder) NAT Part #:D25SV-IKS
Quantity Description NAT Part #
1 D-min 25 Socket Solder Cup 20-20-025
1 25 pin JVL Hood/Locklever 20-29-250
End of section 1.0
Nov 10, 2003 Page 1-5
ENG-FORM: 800-0106.DOT Amendment #2 May 24, 2006
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SM34 Rev. 4.00 AA21-400 Cabin PA System Manual
Nov 10, 2003 Page 2-1
ENG-FORM: 800-0106.DOT Amendment #1 Jan 18, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
Section 2.0 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:
- AA21-400 Cabin PA System
- Warranty Card
- Operator’s Manual
- Release certification
Verify that all items are present before proceeding and report any shortage immediately
to your supplier.
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.
2.3 Installation Procedures
2.3.1 Note to Installers
The AA21-400 is intended for use as a cockpit-mounted control for an internal or
external aircraft PA system, where such a system is not installed to fulfill the
airworthiness requirements for the aircraft or an operating rule.
The AA21-400 is certified to RTCA DO-160D Section 20 (RF Susceptibility) Category T,
for installation in a well-protected electromagnetic environment such as an enclosed
avionics bay in an all-metallic aircraft. The equipment shall therefore not be installed to
satisfy the requirement of FAR 25.1423 for a Public Address system.
2.3.2 Warnings
Never ground any audio output line from the AA21-400 or permanent damage may result.
Always check ADF and compass calibration after installing external speakers or PA
amplifiers. Significant single cycle errors may be caused by the concentration of steel and
magnetic material. Do not bundle any lines from these units with transmitter coax lines.
Do not bundle any lines from this unit with 400 Hz synchro wiring, or AC power lines.
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AA21-400 Cabin PA System Manual SM34 Rev. 4.00
Page 2-2 Nov 10, 2003
ENG-FORM: 800-0106.DOT Amendment #1 Jan 18, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
2.3.3 Cautions
Use shielded cable exactly as shown and ground as indicated. All audio installations
can be severely degraded by incorrect wiring and shielding. Unusual buzzes, hums or
other background audio are symptomatic of multiple grounds, or noisy external systems
such as blowers or pumps sharing wiring with the audio system. Never operate any of
these units below their 8 Ωrated impedance.
2.3.4 Cabling and Wiring
All unshielded wire shall be selected in accordance with AC43.13-1B Change 1,
Paragraphs 11-76 through 11-78. Wire types should be 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 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. To
prevent system failure or inadequate equipment protection, power must be supplied
from a separate breaker or fuse and not connected to any other source.
2.3.5 Post-Installation Checks
2.3.5.1 Voltage/resistance checks
Do not attach the AA21-400 until the following conditions are met.
Check the following:
a) P101 pins <1> <2> and <3> for +28 Vdc relative to ground.
b) P101 pins <14>, <15> and <16> for continuity to ground (below 0.5 Ω).
c) P101 pins <18>, and <22> (with switches open) for infinite resistance to ground (> 10 MΩ).
d) P101 pin <5> to pin <7> for 4 – 6 Ω(typical).
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