the footswitch

 




https://youtu.be/Teu2joRiQj0

This video is, I think, currently the only documentation I have describing the construction of the two-button footswitch for the McGrath Mini.

The video shows the footswitch as it was first built, intended for the Version 1 amp.  As of Version 2, it is similar except the buttons are just labeled "1" and "2" (since they now have varying functions), and the second LED is blue.  The first remains orange; in v1, both were orange.  The resistors setting the comparator threshold in the LM339 circuit are adjusted to make the threshold higher, to operate reliably with the blue LED voltage.

In the video, I say that the construction is "two thick and one thin" layers of plywood, but that's wrong, it's three identical ("thick") layers.


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