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Page 7-6
G1000 System Maintenance Manual
Rev. A
190-00903-00
VHF COM Interference Test
This test must be conducted outside. Use of a GPS repeater inside a hangar may result in a failed
test. Once the signal acquisition test has been completed successfully, perform the following
steps:
1.
On the MFD, monitor GPS signal strength bars on the 3
rd
AUX Page.
2.
On the PFD, ensure that the CDI is set to GPS. If it is not, press the ‘CDI’ softkey until GPS
ENR is displayed.
3.
Verify that the GPS “INTEG” flag is out of view (see Figure 2-1).
4.
Select 121.150 MHz on the No. 1 COM transceiver.
5.
Transmit for a period of 30 seconds while monitoring GPS 1 signal strength levels.
6.
During the transmit period, verify that the GPS “INTEG” flag does not come into view on
the PFD and verify that GPS 1 does not lose a 3-D navigation solution on the MFD.
7.
Repeat steps 5-6 and re-transmit while monitoring GPS 2 signal levels on the MFD.
8.
Repeat steps 4 through 7 for the following frequencies:
•
121.175 MHz
•
121.200 MHz
•
131.250 MHz
•
131.275 MHz
•
131.300 MHz
9.
Repeat steps 4 through 8 for the No. 2 COM transceiver (GIA2).
10.
One the MFD, select the 4
th
AUX page.
11.
Under the COM CONFIG field, change the COM channel spacing from 25 kHz to 8.33 kHz.
12.
Go back to the 3
rd
AUX page.
13.
Select 121.185 MHz on the No. 1 COM transceiver (GIA1).
14.
Transmit for a period of 35 seconds while monitoring GPS 1 signal strength levels.
15.
During the transmit period, verify that the GPS “INTEG” flag does not come into view on
the PFD and verify that GPS 1 does not lose a 3-D navigation solution on the MFD.
16.
Repeat steps 14 and 15 while monitoring the GPS 2 (GIA2) signal levels on the MFD.
17.
Repeat steps 14 through 16 for each of the following frequencies:
•
121.190 MHz
•
130.285 MHz
•
131.290 MHz
18.
Repeat steps 14 through 17 for the No. 2 COM transceiver (GIA2).
19.
On the MFD, select the 4
th
AUX page and change the COM channel spacing back to 25kHz.
