OBERHEIM SYNTH

Could the CPU be getting a spurious reset pulse every now and then?
Also, maybe try programming some new firmware EPROMs, in case the old 
ones are starting to get "bit rot".   Not new code, just newly programmed 
EPROMs, as something to try.   I guess you could also try replacing the 
6809 itself.   There are two of them, so I guess either one could be causing 
your symptoms, right?

Bob


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On Sat, 6/18/16, skoteinos@... [oberheim] <oberheim@yahoogroups.com> wrote:

 Subject: [oberheim] Re: Xpander intermittent boot failures, hangs, memory loss
 To: oberheim@yahoogroups.com
 Date: Saturday, June 18, 2016, 7:01 AM
 
 
 
 
 
 
 
 
 
 
         
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 I replaced the old varistors today, no improvement.