JA95-N70 Audio Controller with RX Volume Controls - NVG
Installation and Operating Manual
Rev
C
Page 7
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 JA95-N70 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
In-Line PTT Cordsets
If in-line PTT cordsets (drop cords) are used, be aware that incorrectly configured or improperly shielded in-line PTT
cordsets can lead to significant audio problems.
2.4.5
Legend Replacement
The JA95-N70 illuminated legends are field replaceable. For further information, refer to the
document in Appendix A of this manual.
2.4.6
Post Installation Checks
2.4.6.1
Voltage/Resistance checks.
Do not attach this unit until the following conditions are met:
a) Check P1 pin
19
for lights buss voltage.
b) Check P1 pin
15
for continuity to ground (less than 0.5
Ω
) when the RX Mute switch is closed, if installed.
c) Check P2 pins
16
&
17
for +28 Vdc relative to ground.
d) Check P2 pin
34
for continuity to ground (less than 0.5
Ω
).
e) Check P2 pins
7 thru 10
for continuity to ground (less than 0.5
Ω
) when the relevant switch is closed.
f) Check all pins for shorts to ground or adjacent pins.
2.4.6.2
Configuration
Ensure that the JA95-N70 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
2.4.6.3
Power on Checks.
Power up the aircraft’s systems and confirm normal operation of all functions of the JA95-N70. Refer to
Section 3 (Operation) for specific operational details.
a) Begin with only the pilot’s headset attached. Confirm correct ICS and radio operation for both receive and
transmit. Check yoke or cyclic switch action. Check the radio selection and inputs. Do not proceed until the
radios are functioning correctly.
b) If there is a music source in the system, turn it on and check for proper mute operation.
c) Unusual buzzes, hums or other background audio are symptomatic of multiple grounds, or noisy external
systems such as blowers or pumps sharing wiring with the audio system. If a transmitter fails to key or correctly
modulate it is often the result of not connecting all required grounds to the radio or external audio system.
d) Check the ICS, RX mute and Emergency operation.
e) Plug in the co-pilot’s headset. Check for correct ICS operation. Check yoke or cyclic switch functions.
