DOM MB Diagnosis page
Board ID:
Rev 5.0 SN 0232
Source:
From STF testing crew
Symptoms:
Fails Local Coincidence Loopback
tests
Analyst(s):
G. Przybylski
Analysis Procedure(s):
Test with terminations on both
transformer outputs. Run both LC transmitters with pulse outputs
of both polarities.
Transmit signal into Z2
looks normal, however Receive signal from Z2 looks distorted (instead
of absent)
Recommend removal and testing of Z2, and checking for shorts on
the board.
Lifted lead of T3 and substituted 75 ohm load on output of Z2.
Waveforms now OK. T3 must be bad.
Root cause:
Defective T3 MUB510D
Mitigation:
Disposition:
Sent to Helen for part removal.
Send to Helen for T3 replacement 9/3/04
Any Other Information:
Travler