- Joined Oct 27, 2009
I am looking for a simple circuit to drive a relay with a potentiometer when at its fully clockwise position. Here is the dealio: I have a quad ganged 1 meg log taper pot, two of the sections of the four ganged pot are used for signal, the other two are free to do what I like with. I need to have the signal pot sections at the extreme fully clockwise to open circuit. To do this I have been modifying the pots by cutting the carbon at the extreme of travel which works fine but is a bit of a pain to do. If I set one of the other unused sections up as a simple voltage divider that when the wiper is in the extreme position (basically shorting the wiper)to one side of the pot it would trigger a relay. I Imagine I could do this with a simple transistor driving a relay. I have a bipolar 15 volt supply in the circuit. I have a pretty good idea with my limited knowledge of electronics of what to do, but I thought I would post this and see if anyone had a simple, proven, low parts count (preferably single transistor) circuit to do this. Any help would be greatly appreciated!