Foxx Tone Machine Bias Mod

[wmoore567]

Hi, i just built my first stompbox, it's a clone of the Foxx Tone Machine, which i bought the parts & circuit board for in a kit from General Guitar Gadgets...

I love the sound, but I wanted to try one modification- I wanted to put a knob on there that would give me a similar effect to the "Sputter" control on the Red Witch Fuzz God II pedal... when the knob is turned up all the way, the fuzz sounds like you'd think a fuzz pedal should; as it is turned down, it, well, sputters... kind of weird mosquito sounds... until it is turned all the way down, you get no volume. But it's a much different sound than turning down the volume or sustain...

I found this post on simple stompbox mods: http://www.diystompboxes.com/pedals/mods.html

Here is the schematic for the pedal I built: http://www.generalguitargadgets.com/pdf/ggg_ftm_sc.pdf?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

So, I took a 1K pot and followed the instructions tying 2 of the legs of the pot together, and ran one of those legs and the third one to either ends of R3, which I removed. I tried it out, and I didn't get the effect I was hoping for at all- the tone changed slightly as I turned the pot from one extreme to the other, but the effect was extremely subtle. Besides that all I was doing was picking up some radio frequencies. Also, the pot was just flying free, not installed in the pedal, so I don't know if the housing of it would be grounded, or if that would affect anything...

Perhaps I should be doing it with a different resistor? or in a different way completely? Does anyone know how to implement a mod which would achieve the effect I'm describing?

Thanks!