Using a 4PDT to switch two pots

Elktronics

Active member
I think it can be done, but I’m struggling to wrap my head around it.

I built a RAH clone from here and love it, I leave it on all the time. What I’d like to do is use a footswitch so that I can have a preset option.

The switch would change from the stock volume and gain pots to a different set of pots set up for more drive and lower volume. This could be done either with trim pots or full size pots

Any clue on if this is doable with a 4pdt switch?
 
Sure. Just leave one lug of each pot connected to the circuit all the time and switch the other two with the 4PDT.

I can draw a diagram later if no one beats me to it.
 
You can do it with a 3PDT also.

 
If you look on the build instruction on that link there is a schematic that is super simple.
 
You can even do it with a DPDT.

If your pot is a voltage divider, use two pots of twice the value and swap the wipers. So, say you have a 100kA volume pot. Parallel lugs 3 and 1 of two 200kA (or 250kA) pots and use 1/2 of the switch for the wipers.

If your pot is wired as a variable resistor, use two pots of the same value and switch out one end.

Edit: also, in the second scenario (variable resistor) if you get a pop on the switch there are a couple tricks you can do. 1) add a 4M7 or 10M resistor between B1 and B3 or, 2) add one 10uF cap before B1 and another one before B3. + ends goes towards the switch contacts.

swap.png
 
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