Warning: long rambling explanation of my Time Machine problems. Please skip it if you're not interested.
Those of you that have this module, maybe you can help me: I just finished building my MOTMized Blacet Time Machine, and I'm not sure if it's working properly. It may well be that I just don't know how to use it, but I've been fooling with it for several days now, and I just can't seem to get a long delay/echo type sound out of it. It does make some sort of trill-like reverby/warble noises that are really cool, but something does not seem right. Here's how I have it set up: standard VCO-VCF-VCA-2EGs patch with the output of the VCA into IN of TM and TM out to mixer/monitors. I'm assuming that I don't need any sort of LFO into any of the other TM inputs to get the standard long and short delays, right? Anyway, assuming that, I have been attempting to calibrate it with the Blacet instructions that say to set the Delay pot to 3, the Regen to 0 (center detent), the Mix to wet, and all other pots CCW. Ok. Then, when adjusting the trim pot (I think it's RT4, I don't have it in front of me right now) until the processed signal can be heard when the Mix pot is fully wet, I hear sound, but no delay. As I turn the delay pot, the sound changes, it makes a sort of warble sound as I move the pot back and forth, but no delay sound. Only when I turn the Regen knob to either the far right or far left to do I start to get any sort of "delay", but this is sort of a trill-like reverb sound that quickly gets distorted. I realize that analog delays are supposed to do something like this, but that is the only effect I can get from this thing. Now, I followed the directions very carefully, checking the voltages on the board before installing the ICs, and calibrating that one trimpot for 10.0V. Then I installed the ICs, and at first only got a really distorted sound that didn't sound right at all. The next morning, when I looked at it again, I noticed that I had installed one of the ICs improperly--one whole side of the chip had the pins hanging over the edge of the socket, not connected. D'oh! So I fixed that, and also loosened the board to re-inspect all my solder joints, and fixed a few that looked less than perfect, checkd the pot wires to make sure they go where they're supposed to etc. After all that, I put it back together and pluged it back in, and it's pretty much as I described above: no delay except when Regen is fully CW or CCW. Just FYI for anyone who is kind enough to help me with this, I did both of Larry Hendry's mods--the bypass switch, and the negative voltage protection (the one with the teepee resistors and 2 diodes, as the one with the "piggyback diode" was double protection and not needed, right?). Also, I built the board before Larry's fine, fine instructions were put up on his site, and when changing some of the resistors required for his mods, a bit of the trace started to come loose from the board. But when I soldered the resistor in place, it seemed to stick down fine, and never broke free or anything. I am relatively new at building MOTM and electronics in general, and thus not very good at diagnosing a problem using the schematics, especially on one as dense and the TM, otherwise I would try to figure this out myself. Could I have damaged the IC that was not seated properly while powering up the module, or could it be one of those traces ∗is∗ broken, or...maybe since I don't have a frequency counter, the 2 trim pots that require one to set them are way out of whack? I just don't know. I tried to give as much info as possible in this post so any potential helpers could help me diagnose this problem. Someone help, please! Thanks, in advance,
Kevin