[sdiy] cv scaler

[Mountain Man]

Thanks very much, Larry  :)  I may take you up on your offer, but I'm
going to
try to use the info from you and Byron "on my own" first.    I've looked
for
LT1013CP in the Mouser catalog, and not found it.  Since I'm putting an
order
together from them anyway, are there substitutes that would do the job
for me?

Thanks again,
Elby


"J. Larry Hendry" wrote:

> This would be a simple circuit composed of a single dual op amp.  I would
> use something very DC friendly like the LT1013CP dual op amp.
>
> Look on my website at my JLH-831 schematics on page 2.   There are 3
> channels of offset in my schematic.  My circuit provides offset in exact
> increments.  Just leave all that stuff out and use a pot for the offset
> voltage.
>
> The pot would be hooked from +15 to -15.  (each end).  The wiper would
> connect to the "A" input of the 831 op amp circuit.  The size of resistor
> R16 would set the range of the offset pot.
>
> To vary the size of the CV, you can vary the size of R14 or R15.  Or if you
> wanted the output to be reversing, take the output of the first op amp and
> the second op amp to opposite ends of a pot with the wiper going to the
> driver op amp stage.
>
> I would be happy to draw this out for you if you need any assistance.
>
> Larry Hendry
>
> http://24.12.85.234/larry/diy.htm
>
> ----- Original Message -----
> From: Mountain Man <mtman at cloud9.net>
> To: synth-diy <synth-diy at node12b53.a2000.nl>
> Sent: Sunday, April 22, 2001 1:06 PM
> Subject: [sdiy] cv scaler
>
> For my next mini-project, I want to build a circuit that will let me
> either amplify or attenuate any control voltage (up to audio
> frequencies), and be able to add a plus or minus offset.  I'm
> envisioning something with two pots - a scale and an offset - both with
> center detents.  With both in the center position, the signal would pass
> unchanged.  Does anyone have a circuit like this, or could someone give
> a beginner enough hints to "build from scratch"?  :)
>
> Thanks much,
> Elby