Installation Manual Part 2

FCC ill: CDG-ARTU

MAGNASTAR

EXHIBIT C

C-2000 DIGITAL AIRBORNE TELEPHONE SYSTEM

5.3

AIU FIELD ALIGNMENT PROCEDURE

The following alignment procedure should be used when an AIU is installed and

interfaced to a HF radio or to other equipment, which will require input from J3 pin 3 of

the AIU. This is a manual alignment procedure that adjusts the audio level that is output

at J3 pin 3 of the AIU. The level of this output audio should be set to the specification of

the extemal device that will be using it.

A. Tools And Required Equipment: The following items will be required:

1. Screwdriver: 1/16 Flat Head Adjustment Tool

2. Volt meter

B. Alignment Procedure: The following procedure outlines the required tasks to

perform this alignment.

Procedure

Using the specification of the external device. which will receive audio from J3

pin 3 of the AIU. note the nominal level which should be applied to its input for

normal operation.

Audio Input Level for the Extmal Device

VAG RMS.

Connect the positive lead of the voltmeter to the AlU test point located on the

side of the AIU case and then place the negative lead on any point of the AIU

case. Set the meter to measure AC volts RMS.

Using one of the MagnaStar handsets setup a HF link:

From the handset's Main Menu,

Press '6' to select the "Link" option.

Press '3' to select "HF Radio" (this label can be customized).

With the HF link now connected continually press (or with ARTC 4.0A software

and above press and release repeatedly) anyone of the handset's numeric

keypad digits to generate a fixed tone. This tone will in turn generate and audio

signal at J3 pin 3 of the AIU.

Using the voltage measurement read on the voltmeter and the adjustment

tool/screwdriver, set the AIU audio output level to the level noted in step 1, by

turning the adjustment potentiometer located through the hole in the AIU cover.

Tenninate the call and remove the meter. Place the adhesive backed circular

aluminum cover PN 513917-2 packed with the unit over the AIU adjustment hole.

5-5

RevB