JA37-300 Aural Message Generator - 3 Channel - Analog Inputs
Installation and Operating Manual
Rev B
Page 5
2.4.2
Cabling and Wiring
All wire shall be selected in accordance with the original aircraft manufacturer’s maintenance instructions, or AC43.13-
1B Change 1, Paragraphs 11-76 through 11-78. Unshielded wire types shall qualify 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 tag ring or equivalent (for shield terminations) to make the most compact and easily
terminated interconnect. Follow the Connector Map in Appendix A of this manual.
Allow 3” from the end of the shielded wiring to the shield termination to allow the connector hood to be easily installed.
Refer to the Interconnect drawing in Appendix A of this manual for shield termination details. Note that this unit has a
‘clamshell’ hood that is installed after the wiring is complete.
Maintain wire segregation and route wiring in accordance with the original aircraft manufacturer’s maintenance
instructions.
Unless otherwise noted, all wiring shall be a minimum of 24 AWG, except power and ground lines, which shall be a
minimum of 22 AWG. Refer to the Interconnect drawing for additional specifications. Check that the ground
connection is clean and well secured, and that it shares no path with any electrically noisy aircraft accessories such
as blowers, turn-and-bank instruments, or similar loads.
2.4.3
Mechanical Installation
The JA37-300 can be mounted in any attitude and location with adequate space for the front panel and sufficient
clearance for the connector and wiring harness. It requires no direct cooling.
2.4.4
Post Installation Checks
2.4.4.1
Voltage/Resistance checks.
Do not attach this unit until the following conditions are met:
a) Check P1 pin
1
for +28 Vdc or +14 Vdc relative to ground.
b) Check P1 pin
14
for continuity to ground (less than 0.5
Ω
).
c) Check all pins for shorts to ground or adjacent pins.
2.4.4.2
Configuration
Ensure that the JA37-300 contains the correct configuration settings. This may be done at the factory, on the
maintenance bench or in the aircraft before the power on checks are performed. Refer to
section 2.5.1.
2.4.4.3
Power on Checks.
Power up the aircraft’s systems and confirm normal operation of all functions of the JA37-300.
a) Check that all configuration settings are correct.
When all performance checks are satisfied, complete the necessary regulatory documentation before releasing the
aircraft for service. Refer to
2.5
System Operation
Many of the System Operation parameters are configured using ProCS™ (see
2.5.1
Configuration Operation
The JA37-300 accepts configuration commands on the Configuration connector via the configuration cable(s) and the
configuration tool (ProCS™) – refer to section 2.6.
2.5.2
Message Mute Operation
The JA37-300 stops playing all messages if the MESSAGE MUTE input is activated momentarily while any
MESSAGE TRIGGER input is active (or when Power On Self-Test is occurring) and stays muted until the next
message trigger event.
