Northern Airborne Technology AMS43 - Manual (Page 5)

AMS43 Single Channel Audio Controller
SM59 Installation and Operation Manual
Section 1 Rev: 1.00 Issue 4 Page 1-1
ENG-FORM: 800-0113.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
Section 1 Description
1.1 Introduction
Information in this section consists of product description, design features and specifications for the
AMS43 Single Channel Audio Controller. 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 AMS43 provides control of 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 Design 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 additional 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.