Garmin GTN 635 Installation Manual page 119

Once the Signal Acquisition Test has been completed successfully, perform the following steps:
1. View the GPS Status Page and verify that at least 7 satellites have been acquired by the GTN.
2. Verify that the GPS ―LOI‖ flag is out of view.
3. Select 121.150 MHz on the COM transceiver to be tested.
4. Transmit for a period of 35 seconds.
5. Verify that the GPS ―LOI‖ flag does not come into view.
6. Repeat steps 4 and 5 for the following frequencies:
For VHF radios with 8.33 kHz channel spacing, include the following frequencies in
addition to those listed above.
7. Repeat steps 3 through 6 for all remaining COM transceivers installed in the aircraft.
8. If aircraft is TCAS-equipped, turn on the TCAS system and verify that GPS position remains
valid (if position is lost, the status on the GPS Status page will change to ―ACQUIRING‖).
9. If aircraft is SATCOM-equipped, use the SATCOM system and verify that GPS position remains
valid (if position is lost, the status on the GPS Status page will change to ―ACQUIRING‖).
If the GPS ―LOI‖ flag comes into view, see 4.11.1 for options to improve performance.
GTN 625/635/650 TSO Installation Manual
190-01004-02
25 kHz COM CHANNEL SPACING
121.150 MHz 131.225 MHz
121.175 MHz 131.250 MHz
121.200 MHz 131.275 MHz
121.225 MHz 131.300 MHz
121.250 MHz 131.325 MHz
131.200 MHz 131.350 MHz
NOTE
8.33 kHz COM CHANNEL SPACING
121.185 MHz 130.285 MHz
121.190 MHz 131.290 MHz
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Rev. C