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Unread 11-04-2006, 22:53
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Re: Potentiometer 5 or 6 detents

Quote:
Originally Posted by Travis Covington
The rotary switch seems like a good solution, if it does in fact have solid feeling stops, so we could easily differentiate between the 6 positions.

The only problem is, I would be the one wiring it up and have practically zero electronics knowledge and would need some help selecting resistors and wiring it up to specific pins on the switch and the RC. If you guys could help me out there, It would be HUGELY appreciated.
The idea here isn't as much the actual resistance as the concept. The current through the circuit I is defined as I=V/Rtotal where Rtotal is the sum of the two resistors: the initial one connecting from 5V to the common lead, and the secondary resistor from the switch to ground. Then the voltage measured at the common lead can be calculated as V=IRswitch (the resistance from the switch to ground). The actual R value will cancel out.

----- Rc ----- Rswitch <--the dashes are just spacers here...
5V--^v^v--|--^v^v--gnd
________Input
Rc=R, Rswitch=#R
I=(5V)/(Rc+Rswitch)
Vinput=I(Rswitch)=(5V)(#R)/(R+#R)=(5V)(#)/(1+#)

Hope this helps.
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Last edited by Adam Shapiro : 11-04-2006 at 23:18.