Tremelo trouble

[Mike Nichting]

Hey all,
I am building a tremelo. Not from any known schematics. I am having trouble with it. I am only hearing a thumping sound where there should be tremelo. The thumping speeds up and slows down when I turn the RATE control but other than that there is no sound. I don't get any sound in bypassed mode either. I am not using a regular 3PDT switch but a SPST switch. It's pretty much the kind of tremelo that is in a tube amp except I'm using an IC (TL072) instead of a LDR/Neon bulb setup like is used in tube amps.
It's a pretty simple design and that is what is driving me crazy that I can't get any sound out of it. If anyone can help out I would appreciate it very much~!!

P{eace,
Mike
NUKLHED

[mikeb]

Schematic?

Mike