Voodoo Labs Tremolo

[fenderguy79]

Does anyone know how I would go about adding a rate blinking LED to this pedal (4 knob version)?  I have not been able to find a schematic thus far.  I'm thinking it would be to tap off the modulating section, and drive the LED using a BJT.

Thanks,
Will

[PRR]

> I have not been able to find a schematic thus far.  I'm thinking it would be to tap off the modulating section

If you can't find a guts-guide (schematic), it may be awful hard to figure where the "modulating section" is and how to connect something to it without messing-up the trem.

[amz-fx]

Find the photocell, which is a black epoxy cylinder with two wires on each end. One end is connected to the audio signal path and the other end is an internal LED.

Once you find the LED end, determine which wire is grounded. Then follow the other wire back to a resistor in series with it. The end of that resistor which is away from the LED is the main modulation point and you can just tap off there and add a new resistor (10k) going to your visible LED and then to ground. You shouldn't need the BJT.

Disclaimer: This is deciphered from a pic I found of the VL tremolo 2 knob version pcb, but I would think the 4 knob is similar.

Best regards, Jack

[fenderguy79]

Thanks Jack!