Northern Airborne Technology AMS43, Installation And Operation Manual

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SM59 Rev. 4.00 AMS43 Single Channel Audio Controller Manual
Nov 10, 2003 Page 1-1
ENG-FORM: 800-0107.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
Section 1.0 Description
1.1 Introduction
This manual contains information on the AMS43 Single Channel Audio Controller. 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 AMS43 provides control for all aircraft audio, allowing selection of transmit (TX) and
receive (RX) audio, LIVE, KEYED, or voice activated (VOX) intercom, interface for an
additional hand-held transmit microphone (hand mic), and pilot isolation/emergency
(ISO/EMR) operation.
TX and PA functions are controlled with a single rotary switch. RX audio, intercom
(ICS) operations and tape audio are controlled with toggle switches. RX volume, ICS
volume and ICS VOX squelch are individually adjusted with rotary controls. Sidetone
(S/T) level is adjustable internally.
1.3 Features
The AMS43 is a Dzus rail mounted unit with a backlit faceplate. Transceiver interfacing
is accomplished through directly switched microphones. To ensure maximum radio
compatibility, it has a ground-referenced keyline that does not incorporate diodes or
other steering components.
Independent control is provided for S/T, ICS audio, and RX audio.
Boom mic support is provided for the pilot and co-pilot, with both ICS and TX functions
via cyclic or yoke switching. Live (Hot Mic) and VOX ICS allow immediate transmission
without further control panel switching, with immediate return to ICS operation on
completion. The ICS function is achieved using dynamic noise reduction and active
filtering. This provides the clearest possible ICS audio under high ambient noise
conditions by rejecting airframe and wind noise, and passing only voiceband
information.
All audio, except the S/T of the radio in use and DIRECT AUDIO 2 input signals, is
muted during TX for clarity. ICS operation allows TX during any ICS mode by using the
TX push-to-talk (PTT) switch.
All external interconnect, switches and relay contacts are gold plated for maximum
reliability. Switches and relays are sealed. G10-FR flame-retardant circuit boards are
postcoated for maximum moisture resistance and corrosion prevention.
Relays are sealed, high vibration rated (50g shock), dry nitrogen filled units.