Thanks for the insight, I'll have to come up with a suitable substitute - turns out the VCO part is not available - the part I had my eye on has +/- a zero vs. the proper part...
http://www.organforum.com/forums/showthread.php?18878-latest-OrganGrinder-listI'll get there eventually!
Elie
--- In yamahacs80@yahoogroups.com, The Old Crow <oldcrow@...> wrote:
>
> The 159 is a linear timing/voltage sequence generator that uses the
> exponential input of the 151 to create the exponential sloped envelopes.
>
> Crow
> /∗∗/
>
> On 11/15/2011 9:16 PM, elie wrote:
> > Hi, I'm implementing a CS-80 Ring Modulator design on another Yamaha Synth. No problem getting the Modulator& buffer amps, VCO chip but the VCA (IG00151)and Envelope Generator (IG00159) are not practical to purchase.
> >
> > My question is if the VCA and Envelope Generator are Linear or Exponential in function?...not sure if the service manual might answer that so just in case anyone knows?
> >
> > Thanks!
> > Elie
> >
> >
>