fixing the footswitch wiring

 


Here is what I've determined about the wiring of the footswitch and DIN plug, along with the changes I'm proposing to make, to render this three-button footswitch more useful for me.

After this rewiring, button 1 will select the "norm" channel, button 2 will select the "lead" channel, and button 3 will select reverb.  There will no longer be control of the phaser.  There won't be a "combine" button per se (since these switches are SPST, not SPDT); instead, the two channels will have independent selection, allowing both to be on at once if desired.  (Also there will be a new both-off mode, maybe useful as a mute function.)

The original four-button footswitch apparently used the cable shield as a different ground for the channel selection, while using pin 1 as ground for the reverb and phaser.  I'm guessing this had to do with noise issues.  I'm hoping there wasn't an actual DC voltage other than 0 on either "ground" line, so that hopefully I can just use the black wire on pin 1 for everything.  If not, well, I guess I'll be back to the drawing board!  (The cable shield is cut short in the current footswitch wiring, but if I have to, I guess I can dig it out and expose it.)


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