Sample And Hold

[abacab]

I build the Sample & Hold for the Sound Lab Mini Synth.
It work for output VCO-1 and VCO-2 but not working for VCF.
When I turn the switch on for the VCF in the Sample & Hold output.
The Cut-Off Frequency go hi and no sample & hold on the filter.
Any Hints.
Thanks

[Pehr]

I think you need negative voltages to get the COF down to the lower freq. I tried to conect a 0 - +5 V source (modulation wheel) to my VCF-CV-input and I only got high COF range, like a wah-wah instead of the mmmwwhhooooaaaa I really wanted...

[Uncle Krunkus]

I've got the same problem with mine. When I get around to it, I'm going to put a little shifter circuit in there to transpose the S&H output down into the -ve ranges.

[Wild Zebra]

Me too, mine is 'patched out' and I can't get it too react too well with the filter.

Oops I edited this cause it said I "can" my badddd

[abacab]

First thank's for the respond.
That's give me some clue.

[sohcahtoa]

What do you guys think is a good solution to this problem?

[Uncle Krunkus]

I know it involves a single op-amp set up as a level shifter with unity gain. Something which I know I'll be able to find when I get around to it, but if someone wants to post an example here in the meantime, it will shorten my search when the time comes.

[skylab76]

Hi guys, any updates on a level shifter circuit? I'm thinking about creating a small level shifter panel with input and output jacks to shift my CV outs which all seem to be 0 to 5V.
I found an op amp based circuit here that goes from -5 to 5V to 0 to 3.3V for ADC applications.
http://www.daycounter.com/Circuits/OpAmp-Level-Shifter/OpAmp-Level-Shifter.phtml

But I get a little nervous messing with the voltages going into my soundlab

UPDATE: Actually, I found a good example, let me try it out, test it (safely outside of SL) , and post it.