If wired correctly, there would be ~0.0v at the gates' inputs with no water detected. If water is detected (or there is a jumper to the drive electrode), there should be ~10V at the gates' inputs. What I was suggesting is a way (+12V through a 10K resistor) to bypass the input's voltage-doublers and try to directly activate the gates. But you did say, you were getting ~+10V on the non-functioning gate's inputs. Was that measured directly on the gates' IC pins, or on other component leads that would be connected to the pins?Your point no. 2 is I think -12V not + 12volts.
by Jake Hertz
by Duane Benson
by Jake Hertz
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