[sdiy] Vactrols subbed for dual-gang pot

[lanterma at ece.gatech.edu]

On Jul 10, 2010, at 12:20 PM, Tom Wiltshire wrote:

> In practice, LDRs are slow to respond to changes (often 10s of mS). If the PWM runs at a high enough rate, the filtering effect of the LDR alone is sufficient to provide the averaging.

Grant Richter constructed a "scanning interpolator" circuit along these lines, using an LM3914 bargraph chip and a clever dithering scheme:

http://www.musicsynthesizer.com/Corpse/VCEOM.html

- Aaron