Posts: 1,083
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Joined: Sep 2006
Until you get some more answers, try substituting the LiIon batteries with some NiCd or NiMH.
The voltage of the LiIon are 1.60 each for a total of 3.2 volts. The design called for NiCd at 1.22 topping out a 2.44 volts.
Normally this would not be a problem but the increased voltage may be to much for the aged circuits. It does sound like a circuit is heating up and then shutting down.
I had a very old Casio calculator (their first battery model). It would only work for 5 minutes until the IC heated and then it shut down. I could get it to work indefinitely if I sprayed the IC with a can of "Cold" (can't remember the brand name) for testing circuits.
My first home computer was a 486 which froze 20 minutes after start up. Shut it down and allow it to cool and it worked again for 20 minutes. Turns out the CPU had 'crept' out of its socket and the heating was enough to disconnect one of the pins. Had to reseat the CPU and all was well.
Cheers, Geoff
Posts: 1,083
Threads: 126
Joined: Sep 2006
George,
It still sounds like a power supply problem and we all know how finicky the Woodstocks are.
I would try tracing the circiuts back from the battery contacts.
Try spraying with a can of Cold spray, various power supply components, when the display appears correct you may have isolated the problem.
cold spray link
It does not sound like the Logic CPU as it cold starts correctly.
Cheers, Geoff
Edited: 8 Sept 2009, 2:38 p.m.
