User's Manual

5-6
5.6
RECOMMENDED PERIODIC CHECKS
Perform local oscillator frequency verification, receive local oscillator frequency verifica-
tion, and transmitter output check 1 year after initial setting and at 5-year intervals
thereafter to correct possible drift caused by aging.
5.7 TROUBLESHOOTING
The digital radio system is equipped with alarm circuitry and automatic switching (in hot-
standby, frequency diversity, and space diversity configurations) to provide protection
against loss of traffic. This automatic switching, coupled with adaptive equalization of mul-
tipath distortion, provides protection against equipment outage and propagation varia-
tions. Because of the finite life of electronic equipment, failures occur.
5.7.1
Test Procedures
All referenced test and check procedures are in Appendix E on attached CD.
5.7.2
Linear/Ring Radio Troubleshooting
Troubleshoot linear and ring radio systems using alarm troubleshooting Figure 5-3
through Figure 5-14. Ring troubleshooting is further explained in the Maintenance section
on the attached CD. After isolating the fault to the most probable cause, replace modules
or repair as directed. The Module Replacement Matrix identifies the alignment procedures
to be performed after a module has been replaced.