4.3.9VHF COMM INTERFERENCE CHECK
a)Go to the Satellite Status Page, verify that 7 to 8 satellites have been acquired
b)See that the “NAV” flag is out of view
c)Select 121.15 MHZ on COMM1
d)Transmit for a period of 20 seconds
e)Verify that the flag does not come into view
f)Repeat steps d) and e) for the following frequencies:
121.175, 121.20, 131.250, 131.275 and 131.300
g)Repeat steps
h)If the “NAV” flag comes into view, refer to Section 2.1.5 for options to improve performance.
4.3.10VHF COMM CHECK
A flight test is recommended after the installation is completed to insure satisfactory performance. To check the communications transceiver, maintain an appropriate altitude and contact a ground station facility at a range of at least 50 nautical miles. Contact a ground station close in. Press the squelch disable button to defeat the automatic squelch feature and listen for any unusual electrical noise which would reduce the COMM receiver sensitivity by increasing the squelch threshold. If possible, verify the communications capability on both the high and low end of the VHF COMM band.
SECTION 5 CERTIFICATION
The GNC 300 is certified for IFR enroute, terminal and
The GNC 300's initial certification was accomplished via a STC by GARMIN in a Mooney M20J. See Appendix C for a copy of the STC.
All installations must be certified. For more information, see FAA Advisory Circular “Airworthiness Approval of Global Positioning System (GPS) Navigation Equipment for use as a VFR and IFR Supplemental Navigation System”, Appendix 1. All new certifications after GARMIN's Mooney installation will be
SECTION 6 CONTINUED AIRWORTHINESS
Maintenance of the GNC 300 is on condition only. Periodic maintenance of the GNC 300 is not required.
Av. Kit Install. Manual
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