bad keys on terminals - test-drb@ccmp.vtda.org

12 Sep 2006

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Subject: Re: bad keys on terminals
   From: "Dave Dunfield" <dave06a at dunfield.com>
   Date: Tue, 12 Sep 2006 05:31:07 -0500
     To: "General Discussion: On-Topic and Off-Topic Posts"	<cctalk at
classiccmp.org>

Dave

BTW: I have similar vintage PETs with identical keyboards in
which the conductive rubber is fine ... anyone know what
conditions accelerate the deterioration of conductive rubber?

Ozone and other airborne contaminants.  I have a old (30 years old)
peice of black conductive foam that is stored in a large jar with 
cmos parts and some dessicant is in perfect condition.  A peice 
...
 from the same block exposed to the air died (crumbled)
over 15  years ago.  

I've also had several keyboards with foam backed pads (Cherry?)
die on me.  Same problem, either the glue dies or the foam.

Allison