[sdiy] New VCO... maybe...

[Shawn Rakestraw]

I am patiently waiting for Mr Hutchins to split the thread off into his own
and lead off with a paper about why making CDs won't work, then explain
that this has already been done.

And PLEASE take this with the humor that I intend it as! No disrespect,
just humor :)

On Wed, Dec 9, 2020 at 6:21 PM Aaron B. <aaron at zadzmo.org> wrote:

> On Wed, 9 Dec 2020 22:56:22 +0100
> Roman Sowa <modular at go2.pl> wrote:
>
> > I haven't used that phrase for long, so here it goes:
> > Comments welcome!
> >
>
> I've got something similar in my notes: I used an MCP602 wired as a
> comparator as well. I only used one opamp section; the integrator was
> just a capacitor to ground, fed by a current source, discharged through
> a 2n7000. No waveshaping as I was intending to drive a digital shift
> register circuit with it.
>
> Messy hand-drawn schematic here: https://ircz.us/AdY3JZw1
>
> I abandoned it as I had a spare LM13700 section and used a simple
> triangle core design with that instead, which performed much better.
> The thought of using the other half of the MCP602 as an integrator
> never occured to me.
>
> In general, I like the idea of 5 volt oscillator cores. Build it around
> it's own TO-92 voltage regulator and basically eliminate power supply
> tuning and coupling issues, then have a TL072 or whatever scale the
> waveform to normal modular levels.
>
>
> Also the trapezoid generator mentioned on the page but not in the
> email: those are underrated waveshapers. Very musical, interesting
> timbres; low parts count; easily made voltage controllable with a VCA.
> They work equally well with sawtooth waves too.
>
> --
> Aaron B. <aaron at zadzmo.org>
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at synth-diy.org
> http://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20201209/aab353cc/attachment.htm>