VCO's for homebuilt synths

[Christopher List]

>On Thu, 10 Aug 1995, SuperBAD MoFo wrote:
>
>> As the Chroma SM put it, the Charge Pump design 
>> is often found in instrumentation, but rarely in synths.  The only catch 
>> is, I don't know how available the charge pump chip...
>
>I've used this design for some of my VCOs, and it works very well.
>The 4151 V-to-F converter has been manufactured by at least Raytheon
>(RC4151) and Exar (XR4151). I've been able to get the XR4151 for around
>$2 in small quantities. There's also the RC4152, which has better
>linearity, but is also much more expensive. National has a second
>source for the latter (LM-something...).


Are schems for this available anywhere on-line? Anyone wanna post 'em?


-Thanks,
Christopher_List @ sonymusic.com