||VCO iss. 3 Expo Cap
| br>Hi, I'm referring to https://www.muffwiggler.com/forum/viewtopic.php?t=163399 where Tony says:
|Synthbuilder wrote: |
|The 2227 is much faster device and can be used for audio and DC.
The extra speed it has over the 2277 won't be noticeable in the VCO as
I slow the output of the expo with a rather large capacitor.
I was trying to figure the time constant, but even failed to find this capacitor on my issue 3 VCOs.
So maybe it's just not on this old version?
Michael. br> br>
| br>It's C4 and a 1nF capacitor on the older issue 3 boards. I use 470pF now... but you can almost certainly go a lot lower. It's there to add stability to the circuit and the value I used was what I have always used because I know it's stable.
I'm pretty sure you'll not be able to work out a time constant since it'll vary with the input voltage. That said I'm a numpty and DC analysis of that circuit is about all I can do.
Tony br> br>
| br>oh, I see! I "ignored" C4 since it's so small and considered it just being there to stabilise the OP.
Then again ... ignorance just didn't help thinking.
"numpty" ... really?? Man ...
cheers, Michael. br> br>