Northern Airborne Technology 270 User Manual

SM270

270
Universal Interface Amplifier

INSTALLATION AND OPERATION MANUAL

REV 4.10 Dec 12, 2006

Northern Airborne Technology Ltd.

1925 Kirschner Road

Kelowna, BC, Canada.

V1Y 4N7

Telephone [phone]

Facsimile [phone]

Copyright 2006 by Northern Airborne Technology

CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.

SM270 Rev. 4.10 Model 270 Universal Interface Amplifier Manual

Northern Airborne Technology Ltd.
has acquired the assets of dB Systems Inc.,
and has revised and reissued this manual in

standard NAT format.

Northern Airborne Technology Ltd.

will be responsible for all future

amendments and revisions.

Dec 12, 2006 Page ii

ENG-FORM: 820-0110.DOT

CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.

SM270 Rev. 4.10 Model 270 Universal Interface Amplifier 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

Number

Amendment

Date

Section(s)

Changed

Date

Entered

Entered By

Insert any Amendment Instruction sheets after this page.

Consult NAT for any questions regarding product revisions prior to

SM270 Revision 4.10.

Dec 12, 2006 Page iii

ENG-FORM: 820-0110.DOT

CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.

SM270 Rev. 4.10 Model 270 Universal Interface Amplifier Manual

Table of Contents

Section Title Page

1 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 1-5

1.4.3 Environmental Specifications 1-5

1.5 Unit Nomenclature 1-5

2 Installation

2.1 Introduction 2-1

2.2 Unpacking and Inspection 2-1

2.2.1 Warranty 2-1

2.3 Installation Procedures 2-1

2.3.1 Cautions 2-1

2.3.2 Cabling and Wiring 2-2

2.3.3 Adjustments and Selections 2-3

2.3.4 Mechanical Mounting 2-4

2.3.5 Post-Installation Checks 2-5

2.3.6 Voltage/Resistance Checks 2-5

2.3.7 Power On Checks 2-5

2.4 Continued Airworthiness 2-5

2.5 Accessories Required But Not Supplied 2-5

2.6 Installation Drawings 2-6

3 Operation

3.1 Introduction 3-1

3.2 General 3-1

3.3 Operation Specifics 3-1

Dec 12, 2006 Page iv

ENG-FORM: 820-0110.DOT

CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.

SM270 Rev. 4.10 Model 270 Universal Interface Amplifier Manual

Section 1 Description

1.1 Introduction

This manual contains information on the Model 270 Universal Interface Amplifier. All
derivative products will be covered by manual supplements, which can be obtained from
NAT as required.

Information in this section consists of purpose of equipment, features and specifications.

1.2 Purpose of Equipment

The Model 270 Universal Interface Amplifier is designed to provide multipurpose
amplification and switching functions for varying radio, microphone, and custom audio
interface needs. The unit is designed to interface radios to operator headsets and
microphones and provide specialized switching functions such as voice activated
switching, radio PTT switching, or other interface functions. The Model 270 can be used
as a primary amplifier for an aircraft or vehicle operator station or it can be used as an
auxiliary amplifier for interface or other applications.

1.3 Features

The Model 270 has Audio, MIC, and Spare Input channels. The Audio Input (receiver)
channel is a balanced (differential) type input; the MIC and Spare Input channels are
single-ended (ground referenced) and designed for interface to commercial DC-biased
microphones or similar low-level audio signals from virtually any source.

Signals applied to the Audio Input channel are reproduced at the Audio Output channel,
the MIC Input channel is reproduced at the MIC Output channel, and the Spare Input is
reproduced at the Spare Output channel. Signals applied to the MIC Input channel can
also be routed to the Audio Output channel by adjusting the MIC SDTN level adjustment
trimmer for the desired audio level.

The Model 270 also includes a multipurpose switching relay capable of performing
different functions. Model 270 functions and specifications are outlined in Sections

1.4.1.1 through 1.4.1.4. A discrete input is provided for controlling the relay in a keyed
mode (e.g. ground to activate or PTT), or alternate action (e.g. latched to another
position with each ground applied). VOX controlled mode (e.g. by audio signals applied
to the Spare Input) is also available. The switching relay can be used to control radio
keying, audio switching, interphone mode switching, music muting, or other specialized
functions as needed.

Dec 12, 2006 Page 1-1

ENG-FORM: 800-0108.DOT

CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.