[sdiy] CMOS as voltage variable resistor

[Grant Richter]

Hi Jurgen,

Thanks you for pointing that out.

> 
> ARP used the 4007 for many applications, including VC resistors.
> (http://home.t-online.de/home/jhaible/hj_qph_1.gif - not the
> original ARP circuit, but the VC resistor part is used as in the
> original.)
>