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Old 06-07-2007, 01:57 AM
Grant Stockly Grant Stockly is offline
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Join Date: Jan 2005
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From: Grant Stockly
Date: Sat, 02 Jun 2007 13:42:24 -0800
Subject: Re: [Altair Computer Club] 88-PPG Troubleshooting

This morning I tried to use the programmer "cold" and it failed. At least
its not "me". The problem is for sure in the programmer or interface
card. The symptom of only programming every other byte and not programming
the bytes that it did do correctly is reflected in the logic analyzer
reading. I have uploaded two more files. One is a picture of the problem
and the other is a 170 second log of what happened on the programmer.

A noticed that quite a few of the ICs legs are tarnished. Some are almost
black. This must have been from an incompatible IC and socket combo. What
is the best way to clean these ICs? Its possible that as things heat up
the legs scrape a little and get better contact? Even if the ICs are
cleaned, a tarnished IC must mean that the socket is bad too, right?

I have a Altair 680 Ram card from Tom that has golden pin ram chips. All
of the chips have pins that are literally cracking off. I would think that
this is because of some anode/cathode thing going on. Its not the gold,
but the steel or what ever the legs are made of. Some crack off and some
even break off when the chips are removed from the sockets. The other ram
card I hvae of his has non gold plated pin 4200 chips and they are all
fine. Same sockets.

Tarnished sockets and pins is something we have to look out for in these
old computers...???

Grant
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