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[Reply #15 on:]

Bell crank linkage to increase pot travel Vs pedal travel?

Lefty

[Reply #16 on:]

Not sure what other vital information I'm with holding

Well there is:-

I just don't have spare pins

and

want to stick to using the analog input

and

that encoders needs to be reset every time to find reference

and

still expensive in time spend building and setting it up

All would have been good to know at the start.

You can use an op amp to add an offset voltage and a reduced Vref. However, that means you need a negative voltage rail so I suppose that rules it out. If not look up "op amps DC offset level shift" for the simple circuits.

[Reply #17 on:]

@Grumpy_Mike: I thought I was quite clear in my initial post that I am using a pot with analogue input. I have years of experience working with encoders to know that it would not suit this application so I did not even consider it. You are right about the op amps though, and I have scrapped that idea.

@Lefty: Yes, this is one of my ideas. I was thinking using R/C servo linkages. Even if it would only give me just under 180degrees of travel on a pot. Problem I got with it is that it might mechanical lockup if you go over the 180 degrees and I might not have the space for this. I have not ruled out this idea either.

@fungus:This is the current idea I am entertaining right now. You get these plastic experimental/educational kits with gears to play with. One I want to try is a straight rail gear which turns a round gear on the pot when the pedal is depressed. Then there are also the toy and R/C electric motor gearboxes. That might also work. Thanks.