Maintenance Manual

INSTALLATION AND MAINTENANCE MANUAL
Tsunami FAMILY
SPREAD SPECTRUM RADIOS
SEPTEMBER 1999
SECTION 4: TROUBLESHOOTING PAGE 4-19
4.9 Back-to-Back Testing
Back-to-back testing, as shown in Figure 4-1, is an ideal method of testing the Tsunami radios.
This testing eliminates link problems caused by auxiliary equipment, installation, or the radio path
and isolates potential radio hardware problems. Back-to-back testing must be performed with both
radios at the same location. The following test equipment is required:
❖ DC power source capable of supplying approximately 90 Watts (total) to the radios (or
two AC adapters)
❖ One low-loss coaxial cable, N-to-N male
❖ One (or more) coaxial in-line calibrated fixed attenuators, 40 to 80 dB total attenuation
The following test equipment may also be useful to perform further testing of the Tsunami radio:
❖ BER tester
❖ Variable (60 dB range or more) RF attenuator (rated for the proper frequency, 2.4 or 5.8
GHz)
❖ RF power meter
Back-to-back testing must be performed to verify a radio
problem before returning any radio to the factory for repair.
When the equipment is connected as shown in Figure 4-1, both Tsunami radios should have no
alarm conditions. When Link Test is enabled at either end, no errors should be registered by the
ERROR indication. If these conditions have been met, then it is likely that the Tsunami radio is
operating in accordance to specifications. If errors or alarms occur during this test, verify that all
DIP switch settings are properly set. If alarms or errors are still present, the radio is likely to be
faulty.
If further troubleshooting is required, a variable RF attenuator can be inserted between the radios
to fade down the path to determine that the threshold specification is being met. The threshold
tests can be run in both directions to isolate the radio problem (if any). More information testing is
provided in Section 4.10. An RF power meter can be used to individually test each radio’s output
power.