OBERHEIM SYNTH

Hi Rich,    I seem to have deleted the old emails.  Just to confirm, you have a later(rev 3 schems) Xa?   And we were talking about U164, right?   Now you 
are saying that only the gnd and +5MEM pins are connected.  Is that correct?The 47 pf cap suggestion was testing delay sensitivity for one of the digitalconnections to that chip, not the power supply.   If only connecting the supplypins makes a difference, then it's a different sort of problem.  On the supply pin,you can use 0.1 uF instead of 47 pf.   Also, +VMEM should already have two capsto gnd, C4 and C5.   Maybe C4 is bad?  Sounds like you need to scope +VMEM.
     Bob


 

     From: "richtrix@... [oberheim]" <oberheim@yahoogroups.com>
 To: oberheim@yahoogroups.com 
 Sent: Wednesday, April 22, 2015 12:25 AM
 Subject: [oberheim] Re: Finding Clock frequency of my OBXa