[sdiy] LFO's showing up on VCO

[Simon Brouwer]

I'd look for varying current into the ground. Even though the ground
conductor has a small resistance, it is not zero, so current running
across it will result in a voltage difference. Thus the ground of the
circuit that generates your CV and that of the VCO's may not be at exactly
the same potential. Assuming no current in the CV conductor, the potential
of the CV will be the same on both sides. So the CV that the VCO sees
(referenced to its ground) will include the error voltage.

Does it help if you disconnect R515 and R615? These would inject about 2mA
p/p of square LFO output into the ground.

Mikhail Novikov schreef:
> Hello!
>
> IMHO, this one should be a very good and universal one.
>
> http://www.ucapps.de/midibox_cv.html
>
> Though maybe this is overkill, cause it have 8 CV outputs.
>
> I am going to build one soon too.
>
> Best regards, Mikhail
>
> On Tue, 11 Nov 2008 22:14:24 +0200, Cory Scott <zjcc56 at mac.com> wrote:
>
>> Hello,
>>
>> Im looking for a cheep midi to cv converter... id like to build one
>> but..im not sure if thats practical... its for a MOTM style synth and i
>> saw the PAIA one and the synthesizers.com one and the polydac etc etc so
>> im expecting to pay around $200..
>> anyone have any ideas?
>>
>> Thanks,
>> Cory
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-- 
Vriendelijke groet,

Simon Brouwer
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