Codan MT-4E, Руководство по обслуживанию

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MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS | MAINTENANCE GUIDE
Chapter 5: Codan Radio System Testing Page 31
In the receiver RSS, enter the Service section and click on “Bit Error Rate”. The receiver frequency
should automatically be shown in the frequency box. Select the Test Type to “Continuous” and Average
Frames to “8”. Click on the “Start Test” button to start the BER test. You should get 0% BER at the -70
dBm default RF carrier level.
Monitor the BER reading while slowly reducing the RF carrier level as shown in Figure 5-14. The
5% BER point should be at an RF carrier level less than the specifi ed Digital Sensitivity point of the
receiver.
Figure 5-14: RSS Receiver Bit Error Rate Test
Enter the Reference Sensitivity (5% BER) reading on the MT-4E Test Sheet.
If the BER measurements are not within Codan published specifi cations, the RF Preselector may need
re-alignment. Refer to the Receiver RF Preselector Alignment and Tuning section.