If a COMM antenna is found to be the problem, a 1.57542 GHz notch filter (GPN 330-
If a COMM is found to be radiating, the following can be done:
1)Replace or clean VHF COMM rack connector to assure good coax ground.
2)Place a grounding brace between the GNC 300, VHF COMM, and ground.
3)Shield the VHF COMM wiring harness.
2.1.6COMM ANTENNA INSTALLATION INSTRUCTIONS
The COMM antenna should be installed according to the manufacturer's recommendations.
2.2RACK CONSIDERATIONS 2.2.1 ACCESSIBILITY
Plan a location which gives the pilot complete and comfortable access to the entire keypad and which is plainly visible from the pilot’s perspective. Check that there is adequate depth for the rack in the instrument panel. A location away from heating vents or other sources of heat generation is optimal. Figure
2.3CABLING AND WIRING
The recommended antenna cable type for both antennas is
U)per
Cabling for the GNC 300 should not be routed near components or cabling which are sources of electrical noise.
Do not route the COMM antenna cable near any ADF antenna cables.
Route the GPS antenna cable as far as possible away from all COMMs and COMM antenna cable.
2.4COOLING AIR
Cooling air is not required for the GNC 300 but is highly recommended because, as with any electronic equipment, reduced operating temperature can contribute to increased reliability. Additionally, location of the GNC 300 in a stack of other power
Av. Kit Install. Manual
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