[sdiy] photo resistor as CV source

[daryl groetsch]

hi all, 
i'm trying to use a photo resistor as a CV source for
my -/+15 Volt modular synth. the circuit i made is
just a >2 Meg photo resistor in series with 2 9 Volt
batteries (18 Volts), with a jack coming off. it works
from about 8 Volts up to 18 Volts, but i can't get it
down to 0 Volts. I tried putting a potentiometer
inline and that lowered it, but not enough. i know i'm
missing something simple probably. can anyone give me
ideas or point me in the direction of a schematic?
thanks very much!
Daryl



		
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