3.5GNC 300 INSTALLATION AND REMOVAL

The GNC 300 is installed in the rack by gently sliding it straight in until it rests against the back of the rack. A 3/32 inch hex drive tool is then inserted into the access hole at the bottom of the unit face. Rotate the hex tool clockwise while pressing on the left side of the Bezel until the unit is firmly seated in the rack.

To remove the unit from the rack, insert the hex drive tool into the access hole on the unit face and rotate counter-clockwise until the mounting screw turns freely and the unit protrudes about 3/8 inch from the panel.

Be sure not to over tighten the unit into the rack. The application of hex drive tool torque exceeding 15 in*lbs can damage the locking mechanism.

3.6COMM ANTENNA INSTALLATION CHECK

Check for insertion loss and VSWR. VSWR should be checked with an in-line type wattmeter inserted in the coaxial transmission line between the transceiver and the antenna. Any problem with the antenna installation will most likely be seen as a high reflected power. A VSWR of 3:1 will result in a 25% loss in power.

SECTION 4 POST INSTALLATION CONFIGURATION & CHECKOUT

PROCEDURE

Before starting the below operations, unit initialization must occur. Do this by first removing any data cards and then turning the unit on. Press enter in response to “Select operating mode Normal ok?”. Press enter in response to “No Jeppesen database rte/prx limited to user wpts ok?”. After the satellite status page is displayed for 5 seconds the unit may be turned off. Proceed with the following steps.

4.1TEST MODE OPERATIONS

With power applied to the aviation rack and the GNC 300 unit off, depress and hold the ENT key and turn the unit on (release the ENT key when the display activates). The first page displayed is the Display Test Page. While in TEST MODE, test pages can be selected by ensuring the cursor is off and rotating the outer knob either direction. To change data on the displayed test page, depress the CRSR key and the cursor will highlight the standby COMM frequency. Press cursor again to move to configuration selections. The inner knob will change the data on the selected field. The ENT key or the outer knob will advance to the next field on the page. Pressing the CRSR key again will stop the current field from flashing, allowing the outer knob to select the next test page. The ENT key is used to enter a new value into the OBI data field after selecting the desired value using the inner and outer knobs (see the appropriate chapter of the Pilot's Guide for more information on page and data selection). Note that some pages found in test mode are intended for bench testing and are not discussed here.

Av. Kit Install. Manual

190-00067-02 Rev. J

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