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Appendix H: Viavi CX300 Tests
MAINTENANCE GUIDE | MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS
Reference Oscillator Adjustment
In the transmitter RSS, enter the Service section and click on “Ref Oscillator”. The reference oscillator frequency
is shown as the “Target Frequency”. Enter this RF frequency into the CX300. Click on the “Key Tx” button and the
transmitter will generate the reference frequency out of the RF output into the CX300.
Monitor the RF Error on the CX300. To change the reference frequency, adjust the softpot slider in the RSS as
shown in Figure H-23.
Figure H-23: RSS Transmitter Reference
Oscillator Alignment
Adjust until the RF Error is as close to 0 Hz as possible. Click on the “Program” button to program in the new
Reference Oscillator softpot value.
Enter the Carrier Reference Oscillator Offset reading on the MT-4E Test Sheet.