Tonepad Tremulus Debug

[ParlorCitySound]

Tremulus Lune (Tonepad Version)

Layout/Schematic
http://tonepad.com/getFile.asp?id=84

Modifications: Symmetry mod w/out fine knob.
I found the diagram for this in an older post. I did it per this: http://i176.photobucket.com/albums/w196/pbody_pics/circuits/LUNE_MODS2.jpg

What it is doing: It passes sound when bypassed just fine. No sound when the effect is on. The knobs seem to effect the speed LED logically. The speed knob makes it blink faster. Symmetry knob has an obvious effect (hard to explain). Smooth makes the blinking...smoother.

What I have Done: I looked for any obvious mistakes (IC's are in place). Reflown nearly every solder joint. Looked for solder bridges.

Voltages: (all voltages read with speed knob at max. voltages in red are approx. voltages when speed knob is half way up)
Battery - 8.59v

IC1 (TL072CP)

1 - 4.34
2 - 4.34
3 - 4.14
4 - 0
5 - 4.11
6 - 4.30 (this leg crackled through the amp when I touched the probe to it)
7 - 4.26 (I read pin#7 should change with turning the "spacing" knob. It did not)
8 - 8.58

IC2 (JRC4558D)

1 - 4.19 3.0-5.5
2 - 4.19 3.5-5.5
3 - 3.49 3.0-4.5
4 - 0
5 - 3.44 2.0-4.5
6 - 6.48 3.0-6.0
7 - 4.30 1.0-8.0
8 - 8.55

Any help would be great. Thanks!

[MikeH]

Did you check for proper orientation of your opto resistor?  One side has a corner angled off, and this is supposed to correspond with the anode of the LED.  IIRC on the tonepad version, this orientation causes the printing on the opto resistor to face down against the board, which is a problem that some people run into, because they install it with the writing face up.

Other than that, I'd try an audio probe and find out where you're losing signal.

[ParlorCitySound]

Thanks Mike! Flipped it around and viola!

I didn't give it much thought as the text on the actual VTL5C2 has "LED+" on the cathode side, while the angled corner is on what I thought to be the cathode. I can honestly say debugging something like that will make your solder joints absolutly perfect when you start redoing them 3-4 times making sure they are flawless.

[MikeH]

Yay- that was easy.