Hey there all,
Myself and a friend are trying to build a bar (or at least a beer tap) into a working piano. we currently have a servo rigged up to pull the tap of the kegs set up and working. i am using a setup i found ( http://makezine.com/projects/control-a-servo-motor-without-programming/ ) here to use a pot to control the servo but i am looking to make it work by pressing a key on the piano. my thoughts are that i could have two pots both set to the two positions that i need them to be and have it so when you press the piano key it would bypass the first pot that is set to first position and bring the second pot into play. I am not really sure how to do this but i essential just want a way to wire a switch between the two pots and the servo. Any suggestions?

cheers

 

Are pots connected as rheostats?

 

Thanks for the reply and diagram. I am pretty sure the diagram i found for this setup uses all three of the terminals on the pots so it wouldnt be as rheostats

 

Do you need the smooth motion from the servo or just have it move to one of two positions? The latter is easy to do. You can replace the fixed resistors in this example with pots wired as variable resistors ( as in an earlier post) for adjustment. Take a look at these diagrams.
http://m.instructables.com/id/Using-Servos/step7/using-a-555-and-push-buttons/
Or
http://www.555-timer-circuits.com/images/ServoTester.gif

 

Then use a double throw switch.