Amp footswitch reversed LED operation

[rockhorst]

A guy asked me the following today: he has a footswitch that switches between rythm and lead channels of his amp. The LED turns on when in rythm mode and turns off when in lead mode. Quite understandably, he would prefer it the other way round. Is there a way to do that without changing the footswitch loop of the amp itself?
The footswitch at the moment works like this (from amp = ring, to amp = ground).

I was thinking this might work, but I know to little about actual footswitch design at the amp side to know for sure (no, I don't have the amp to check it at the moment):


Any thoughts much appreciated.

[trixdropd]

I doubt it because of the fact that the amp is supplying the voltage to the led. if he were to add dc or a battery to his pedal and up the switch to a dpdt or a 3pdt this would work. maybe someone knows more than me, as i've only built a few amp footswitches.

[rockhorst]

Hey Trixdropd: I was thinking the same thing, but adding an external power part to the switch seems a bit beyond the point. I was thinking that maybe I can use a resistor that can drain all the excess voltage. But that wouldn't work if the amp actually switches by sensing current. And I don't know how that part of an amp works. Thanks for thinking along!

[trixdropd]

Hey Trixdropd: I was thinking the same thing, but adding an external power part to the switch seems a bit beyond the point. I was thinking that maybe I can use a resistor that can drain all the excess voltage. But that wouldn't work if the amp actually switches by sensing current. And I don't know how that part of an amp works. Thanks for thinking along!

the voltage drain could potentially stop the amp from switching, as many use relays for the switch.  The real question I would have in you proposed scenario  is you wanna drain the voltage on 1 end, but on the other end  where you gonna get the voltage? I think a battery and a switch upgrade solves this with no headeache.

[nico13]

Disconnect the wire coming from the tip (or ring) of the jack from the switch and insert your LED between them.

The anode of the LED soldered on the tip (or ring) wire and its cathode on the switch.

I can tell you that works for Peavey Footswitch.