Hi All Here's the problem: I want to control a potentiometer with a foot pedal. Pot is read by Uno analog input. If I connect the potentiometer direct to the foot pedal axis, I will get a a range of about 40 degrees movement on the pot. This is actually 20 degrees forward and 20 degrees backwards with center off (for forward and backward speed control). I know there are commercial products out there such as actuators and foot pedals as well as means to extent the range of the pot mechanically, but this is a hobby project and I want to keep cost low and mechanically simple.
40 degrees on a standard 270 degree pot translates to a value of about 152 in the ADC register. This is too small for me, I would like to use as near to full range of the register as I need presision (well 70-80% will still be good).
My other idea is to electronically amplify this with opamps but I must have been sleeping when we studied opamps in class all those years ago. I can not come up with a circuit.
So, anybody got any ideas? With opamps, I want to input say 2.5V-3.5V and want to circuit to output about 0-5V which I then use as analog input. Upper and lower limit must be adjustable. What would you call a opamp circuit like that (since just about all opamp circuits got names :) )