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Tam/WB2TT Tam/WB2TT is offline
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Default Repairing mylar cable?


"John E." wrote in message
obal.net...
Cable was damaged by melting several (6) traces worth of conductors. It's
part of an expensive controller assembly for which no individual
replacement
parts such as this are available. Terminated end is under membrane switch
panel which is affixed to the front of the controller. Disassembly to
reach
the other end of the cable would be near-destructive.

So I'm resolved to fix it. The best approach I can think of is to scrape
away
the light protective coating over the conductors (which aren't copper PC,
but
some painted-on conductive substance) but not scrape too deeply (I've
found
by experimenting that this is Not Good )c: ) and affix 30 ga wires via
conductive epoxy, bridging the damage.

I dread this approach because of the fine pitch of the conductors, and not
knowing until I've finished each patch whether 1) there remains enough
conductor to patch and 2) the epoxy "took".

There is about 1 inch undamaged conductor on either side of the damage to
effect a connection, so if any one attempt at bridging a conductor fails I
can attempt another, if need be.

It's going to be rough going, I fear.

Any other suggestions? Maybe find source for this type of cable and graft
it
to the existing one?

Sources for these cables?

Thanks,
--
John English

I can't quite visualize your cable, but can you cut it at the bad spot, and
clamp it between two pieces of PC board, where one or both PC boards have
traces on them that line up with your conductors? The connection would be
made by compression.

Tam