Another optional step. On the underside of the upper PCB, there is a small black circle (inside the pink scribble on the photo) with two bare wires coming out of it. If you look closely, you'll also see that there is a + and a - marked on the PCB next to those wires. The wires are coming from a small bulb inside the black box on the other side of the PCB. The bulb pulses according to the settings of the pots, and that in turn modulates the vibrato effect.

As the bulb pulses, it provides a visual indication of how you have the pedal set (very useful if you are playing on stage, and aren't able to bend down to see where the knobs are set). Cool, sure, but with the original design, the bulb is hidden inside the pedal housing, so the user will never know, visually anyway.






The solution is to attach 2 wires, a resistor, and an LED. Just connect one wire to each of the small bare wires coming out of the black circle. (One wire must have the resistor on it, or you'll smoke the LED). Now the new LED will display the "tempo," for lack of a better term, of your pedal as it's operating.

A few rehousing tutorials recommend that you tinker with the bulb assembly and the thingy inside it (called an LDR). Usually the rationale has to do with getting a brighter light, or making the interior of the black box more reflective. That sounds promising in theory, and who doesn't like a good reflection? In practice, the results are somewhat uneven, so I don't recommend it.