I have an audio mixer with a mono jack output which enables me to turn off the reverb between songs when I just want to speak to the audience. I have a momentary foot switch plugged in, which just shorts the signal for however long you push down on the switch. It basically toggles between two states internally in the mixer. When the reverb is off, there is an LED indicator that switches on. The problem is that the indicator on the mixer isn't always visible from the stage, so it's difficult to tell if the reverb is on or off. I've been wanting to add an LED or two to the switch itself. I've discovered that there is a 5v signal coming out of the mixer into the switch. When the switch shorts the signal, the reverb goes on or off on the mixer. I have an extra CD40106 hex Schmitt trigger that I thought might be useful, but since it needs a power supply that's always on, I guess I won't be able to use it as a toggle switch in this case. The circuit inside the mixer is able to toggle using a 5v signal that is momentarily shorted. Is there an easy way to do this electronically? It's also a very small foot switch with not a lot of room for electronics and no room for a battery.