[tech] circuitry...

[Alexander Hill]

I haven't done EE yet, heh. Hoping one of you guys can help me out.

I'm trying to build a footswtich for a Peavey Envoy 110 amp. The
footswitch has two functions - to select and deselect the lead channel,
and to enable and disable reverb. LEDs indicate the status of each.

The footswitch is connected to the amp via a stereo cable. That is,
three conductors; in this case we'll call them lead, reverb, and ground.
There is +15V from the lead wire to ground; the reverb wire is neutral.

When the lead and ground are connected, the lead channel is selected.
When the reverb wire is connected to ground, the reverb effect is disabled.

The problem here is that there is no voltage in the reverb wire. So, how
can I tap the power, as it were, from the lead wire, and light the
reverb LED (when the reverb loop is open)?

Attached is a rough attempt...it doesn't work. The LEDs do weird things
which I can't recall at this moment, but it might give you more of an
idea of what's going on...

Any help would be fantastic. Sorry for the strange formatting, heh.

Alexander Hill
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