Tektronix WVR4000, Руководство по обслуживанию

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Maintenance
Table 4: Symptoms and causes
Symptom Possible Sources or Recommended Detailed Troubleshooting Procedure
No LEDs lit Perform general checks
Perform power supply checks
Replace the front panel board as indicated by the test results from the above tests
Inconsistent or partial hardware
failures Perform power supply checks
Examine Power On Self Tests (POST) results in the Diagnostic Log
Replace main board
Fails any of these Power On Self
Tests (POST):
Timecode Decoder Comm
SDI Deserializer Comm
DSP FPGA A Comm
DSP FPGA A Program
Display FPGA Comm
Display FPGA Program
Review messages in diagnostic log
Perform power supply checks
Replace the main board
Functional Test Failures
PVD Test Failures In case of failure on either Functional or the Performance tests, the board at fault is generally
obvious. Before replacing a board:
1. Perform the power supply check.
2. Check the diagnostic log for help in isolating the fault.
If those do not isolate the problem, then replace the main board if the test is in one of the
following areas:
SDI
REF
DVI
LTC
If the problem is only the SDI input, fi rst replace the SDI I/O board. If that does not fi x the
problem, replace the main board.
If the problem is only the reference input, replace the Ref I/O board. If the problem persists,
then replace the main board.
If there is no XGA output, replace the DVI I/O board. If that does not
fi x the problem, replace
the main board.
If the problem is in audio, perform the steps in the Audio Troubleshooting section.
Unknown Problems
Often an instrument will come into
service with vague or intermittent
symptoms. In cases like these,
the following set of tests may help
fi nd the problem or the marginal
condition.
1. Check the diagnostic log. This log records a variety of problems and will enable you to see
messages for an error that may not be currently happening.
2. Check the power supply by performing the Power Supply check. A marginal supply can lead
to intermittent operation if it is near the acceptable threshold.
3. Run the functional test. This will exercise a majority of the functions in the instrument and
includes the diagnostics. Some parts of the test may not be necessary for all problem areas.
14 WVR4000 and WVR5000 Service Manual