On Wed, 7 Jan 2009, Josh Dersch wrote:
Yet another small repair question --
Picked up an Osborne 1 with a non-functional keyboard. Upon opening
it, I found that one of the plastic/membrane keyboard ribbon
connectors had cracked partially through near where it plugs into the
PCB.
Since these ribbons are actually part of the membrane of the keyboard
I can't just replace the cracked ribbon -- so the only option appears
to be to re-cut the end of the ribbon cable and expose a bit of the
conductive material. What's the recommended means to expose the
conductive stripes at the end? I've tried gently scraping with the
tip of an x-acto knife but it either does nothing or takes everything
off the end :).
Are you sure the ribbon is actually a "sandwich"? My Tandy CoCos and
Atari 800XL units have a similar flex ribbon where the conductors are
on the top surface. I've been able to simply cut them back and
reinsert the remainder. (I initially went down the same path and
tried scraping them - with similar results <g>).
Steve
It's not a sandwich, but there's definitely some sort of coating over
the conductive stripes -- I get nothing out of my continuity tester by
touching the probes on opposite ends of a given stripe. Hmm.
Josh