DOM MB V5 Diagnosis
page
Board ID:
V5 00242
Source:
Azriel Goldschmidt
Symptoms:
After ATWD 0 replaced, still fails ATWD 0 STF tests
Analyst(s):
G. Przybylski/George Chao
Analysis Procedure(s):
While running STF tests, probe
signals at ATWD input test points, and control input voltages.
The Trigger Bias level on ATWD 0 was anomylous, however the voltages at
the controlling DAC were reasonable (matched the values for ATWD B).
While probing ATWD 0 pin 22, Q9 was noted to be standing on two leads,
instead of three (tomb-stoned).
After Q9 was soldered back down, the board was retested with STF, and
found to have one bad channel on ATWD 0.
Control voltages were rechecked. No surprises here.
Recommend replacing ATWD 0 again. then retesting.
George Chao helped diagnose this board; taking a dive off the
deep end :-)
Root cause:
Tomb-stoned component
Mitigation:
Repair
Disposition:
SOFTWARE Test ONLY, since the
board
Any Other Information:
Traveler
