Northern Airborne Technology 246 - Manual (Page 11)

Model 246 Isolation Amplifier
SM246 Installation and Operation Manual
Section 2 Rev: 1.00 Issue 2 Page 2-5
ENG-FORM: 805-0115.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
2.4.7 Post Installation Checks
If any preset requires adjustment, be sure this is carried out before the aircraft leaves, and that the unit
and its mating connector are secured before departure. Make all required log book entries, electrical
load, weight and balance amendments and other paperwork as required by your local regulatory agency.
2.4.7.1 Voltage/Resistance Checks
Do not attach the Model 246 until the following conditions are met.
Check the following:
a) Check pin for +28 Vdc relative to ground.
b) Check pin
for continuity to ground (less than 0.5 Ω).
2.4.7.2 Power On Checks
WARNING:
High volume settings can cause hearing damage.
Set the headset volume control to the minimum volume setting prior to
conducting audio tests, and slowly increase the headset volume level
to a comfortable listening level.
Power up the aircraft’s systems and verify normal operation of all functions of the model 246.
Upon satisfactory completion of all performance checks, make all required log book entries, electrical
load, weight and balance amendments and other documentation as required by your local regulatory
agency before releasing the aircraft for service.
2.5 Adjustments and Connections
2.5.1 Mechanical Installation
The Model 246 may be mounted and operated in any position; however, access to the gain adjustment
should be considered. The amplifier chassis must be electrically bonded to the airframe. The finish on
the chassis is electrically conductive and need not be removed for electrical bonding. If the Model 246
will be driving more than approximately 2 Watts into a load, it is recommended that the unit be mounted
on a metal surface of no less than 100 square inches.
2.5.2 Adjustments
2.5.2.1 Internal Gain Adjustment
The Model 246 has an internal gain adjustment, accessible through an opening in the cover.