Page 3-8 500 SERIES INSTALLATION MANUALRev Q 190-00181-023.7 RACK INSTALLATION1. The back plate of the rack may optionally be removed for ease of mounting in the aircraftpanel. To do so, remove the two #4-40 screws, tilt the back plate away from the tray, and thenslide the back plate to the side.2. Figures F-2 and F-3, starting on page F-5, shows outline dimensions for the aviation rack forthe various 500 Series units. Install the rack in a rectangular 6.320” x 4.600” hole (or gapbetween units) in the instrument panel (refer to Figure F-6, page F-13). The lower-front lip ofthe rack should be flush with, or extend slightly beyond, the finished aircraft panel.CAUTIONIf the front lip of the mounting rack is behind the surface of the aircraft panel,the 500 Series unit connectors may not fully engage.Make sure that no screw heads or other obstructions prevent the unit from fully engaging in therack. Exercise caution when installing the rack into the instrument panel. The rack is designedto facilitate removal of the 500 Series for use in Demo Mode outside the aircraft. Deformationof the rack may make it difficult to install and remove the 500 Series unit.3. Install the rack in the aircraft panel using six #6-32 flat head screws and six self-locking nuts.The screws are inserted from the inside through the holes in the sides of the rack.4. If the back plate was previously removed (see step #1), replace the back plate by positioningthe tabs on the back plate in the slots of the left side of the rack (viewing it from the cockpit)and attaching it by replacing the two #4-40 screws.3.8 500 SERIES UNIT INSERTION AND REMOVALIt may be necessary to insert the hex drive tool into the access hole and rotate the mechanism 90°counterclockwise to insure correct position prior to placing the unit in the rack. The 500 Series unit isinstalled in the rack by sliding it straight in until it stops, about 1 inch short of the final position. A 3/32”hex drive tool is then inserted into the access hole at the bottom of the unit face. Rotate the hex toolclockwise 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 rotatecounterclockwise until the unit is forced out about 3/8” and can be freely pulled from the rack.Be sure not to over tighten the unit into the rack. The application of hex drive tool torque exceeding15 in•lbs can damage the locking mechanism.3.9 COM ANTENNA INSTALLATION CHECK (GNS 530)Check for insertion loss and VSWR (voltage standing wave ratio). VSWR should be checked with an in-line type VSWR/wattmeter inserted in the coaxial transmission line between the transceiver and theantenna. The VSWR/wattmeter should be inserted as close to the transceiver as possible. When rack andharness buildup is performed in the shop, the coax termination may be provisioned by using a 6” inlineBNC connection. This would be an acceptable place to insert the VSWR/wattmeter. Any problem with theantenna installation is most likely seen as high reflected power. A VSWR of 3:1 may result in up to a 50%loss in transmit power.