OBERHEIM SYNTH

I helped a friend fix his Xa.   We found a bad 2114 RAM chip, and 
also a chip on the lower board that was shorting one of the data bus pinsto gnd, and bringing the whole system down.  We had to cut traces to 
isolate which chip it was, since that one bit went to a number of 
chips, and none of them were socketed, and also the cable between 
the bds was soldered at both ends.  Hate doing that, but we did it 
discretely and got things going again.
    Bob

      From: "synthparts@yahoo.com [oberheim]" <oberheim@yahoogroups.com>
 To: oberheim@yahoogroups.com 
 Sent: Friday, October 3, 2014 1:07 AM
 Subject: Re: [oberheim] OB-Xa LED error code at boot time?
   
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The OB-Xa doesn't have any error reporting ability other than blinking the voices which can't tune during the auto-tune routine. Possibly bad CMOS, ROMs, RAM, or Z80. I've seen failures in all of those on Xas.
Doug synthparts.com