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View Full Version : Osborne 1 keyboard fix (tip)



Roland Huisman
September 13th, 2012, 01:15 PM
My Osborne 1 had a strange problem. When I typed DIR I got KDIER.

Some letters like the K and D both gave KD. So i tought some
scanlines were connected together. And yes, after some measurments
it seems there is a weak connection between pin 3 and 7 from the second flatcable.
Approx 750 Ohm

10256

I think this is some moisture damage. Some oxide between two lines.
But how do I remove it? It's impossible to disassemble the keyboard itself.

So I'd put a 35V voltage between the lines, hoping the short will disappear.
And YES! It did. the keyboard is functioning normal again.

Regards! Roland

patscc
September 13th, 2012, 05:16 PM
Congratulations! Nice fix.
patscc