[sdiy] Weird MFOS VCO max CV problem

[Travis Thatcher]

I've had a MFOS VCO in my rig for some time now and its more or less 
been functioning well.  I finished it as a build a friend started and 
had some initial problems but after going through the circuit everything seemed to be okay. The problem I'm having is that if you feed it a CV 
above a certain threshold, when the pitch is high, the VCO just turns 
off. I suspect the summing op amp for CV is just getting stuck in a 
state where its hitting the rails, but I've tried a few different chips 
to be sure that's not the issue.  Not really sure where else to poke 
around to troubleshoot this. Has anyone else ever had this problem?

Travis Thatcher
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