[sdiy] How To Make This Oscillator into a VCO

[patchell]

    I was wrong, this circuit will work with any opamp.  If you look in your 1982
National Semiconductor Linear Data Book on page 3-32 ( LF356) you will find a
similar VCO.

patchell wrote:

>     I would have to look at the circuit again...but I think that the common
> mode input range needs to include the negative voltage terminal on the opamp.
> This is strictly a single supply type application, although, I could be wrong.
>
>     One big disadvantage of this circuit is that it is stricktly linear
> response.
>
> Gavin wrote:
>
> > Wow! nice circuit, now ill this work with other op amps?  or is it specific
> > to the properties of the lm324?
> > ----------
> > >From: patchell <patchell at silcom.com>
> > >To: bill berzinskas <housenationmedia at yahoo.com>
> > >Cc: synth-diy at dropmix.xs4all.nl
> > >Subject: Re: [sdiy] How To Make This Oscillator into a VCO
> > >Date: Sat, Oct 19, 2002, 4:46 PM
> > >
> >
> > >    Yes it can...look in a National Semiconductor data sheet for the
> > >LM324.  There is a VCO that will produce a triangle that uses no OTAs.
> > >In fact, this is what I built for my first synthesizer back in 1974.
> > >Worked a lot better than the Paia 2720 oscilator...in some ways.
> > >
> > >bill berzinskas wrote:
> > >
> > >>    Thanks for all the good responses..  tons of good info..
> > >>
> > >>
> > >>
> > >> Next Question:   Can this be done without an OTA?  For the most part,
> > >> i'm working with standard opamp pieces..
> > >>
> > >>
> > >
> > >--
> > > -Jim
> > >------------------------------------------------
> > >* Visit:http://www.silcom.com/~patchell/
> > >*-----------------------------------------------
> > >*I'm sure glad Merry Christmas comes just once a year
> > >* -Yogi Yorgensen
> > >------------------------------------------------
> > >
> > >
>
> --
>  -Jim
> ------------------------------------------------
> * Visit:http://www.silcom.com/~patchell/
> *-----------------------------------------------
> *I'm sure glad Merry Christmas comes just once a year
> * -Yogi Yorgensen
> ------------------------------------------------

--
 -Jim
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* Visit:http://www.silcom.com/~patchell/
*-----------------------------------------------
*I'm sure glad Merry Christmas comes just once a year
* -Yogi Yorgensen
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