Northern Airborne Technology AMS43, Инструкция по установке и эксплуатации

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AMS43 Single Channel Audio Controller Manual SM59 Rev. 4.00
Page 2-4 Nov 10, 2003
ENG-FORM: 805-0106.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
2.3.5.2 Power On Checks
Power up the aircraft's system with the unit installed, and turn on the radios and
accessories required for the system. Refer to Section 3.0 for operation and set-up
information.
Start with only the pilot's headset installed. Check for correct Intercom (ICS), radio, and
transmit (TX) operation. Do not proceed until the radios are functioning correctly. The S/T
trimpot accessible through the left side of the controller and the transceiver internal trimpot
may have to be adjusted for correct balance for the pilot. Adjustment of the individual radio
receive (RX) levels should be set first with the AMS43 in
PILOT ISO/EMR (Pilot
isolate/emergency) mode, then adjust the AMS43 front panel RX master volume control
level in
NORMAL mode.
Unusual buzzes, hums or other background audio are symptomatic of multiple grounds
or noisy external systems sharing the same wire bundle. Incorrect jack wiring is a
common fault, especially for passenger stations, and may cause loss of audio, a tone
on the headset lines, or other problems. Failure to key or correctly modulate a
transceiver may be caused by missing grounds on the radio or audio controller.
Plug in the hand mic and test for correct operation. Wiring faults for this accessory may
cause peculiar loss of ICS or TX functions because it has over-riding priority in the
system.
Plug in the remaining headsets and check for proper operation. An incorrect drop cord
or improper jack wiring may cause a wide range of problems from loss of audio to a
tone heard in the headset. For further information, see section 2.3.6 below.
Check levels and operation of all functions in flight to ensure proper adjustments and
settings have been made.
Upon satisfactory completion of all performance checks, make the required log
entries and complete the necessary Regulatory Agency paperwork before
releasing the aircraft for service.
2.3.6 In-line PTT Cordsets
2.3.6.1 General
In-line, push-to-talk (PTT) cordsets (also known as drop cords) can be used to
create/provide PTT capability for the user headsets that do not have yoke or cyclic
mounted PTT switches. For headsets connected to the PILOT or COPILOT
inputs/outputs of the AMS43, ICS and TX keylines are needed to properly activate the
associated PTT circuitry inside the AMS43. For headsets connected to the
PASSENGER inputs/outputs of the AMS43, a method of controlling the microphone on
the headset is needed because of the 'hot mic' circuitry. This is best accomplished with
a 'mic interrupt' switch in the PTT cordset.