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Lostgallifreyan Lostgallifreyan is offline
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Default help diagnose old circuit board, fault

"James Sweet" wrote in
news:2B1Fi.3192$qV3.2218@trndny02:

one interesting thing i noticed is one of the alphanumeric LED cells
has artifacts (slight glowing) displayed in it and the artifacts
shimmer and change slightly when a BAD buton is pushed could this
indicate a failure of
some component ?



Sounds like there might be a missing ground, which would cause current
to flow down paths it shouldn't. It's common for problems like this to
be caused by cold solder joints or hairline fractures in circuit
boards, I'd start by touching up any suspect joints.


Exactly. As well as what I said in my other post, look for other possible
stress points like the one by the failed switch group, there might be more
about to fail, and reworking the connections is far easier and faster than
doing elaborate diagnostics which you might never have to do.