Hi all, I'm building the U-boat using the layout from the blog. Only changes I have made from the posted layout are:
- NE5532 in place of LM833
- TL084 in place of TL074
Everything else is identical. I made a lot of mistakes in my initial build, but I believe I fixed them all and have been over my build many times carefully. The problem is I'm not getting a lower octave. With the mix all the way to the octave side I get a dull, fuzzy unison tone. The DPDT switch doesn't seem to make any audible difference in tone, and the tracking pot has no effect on the results.
The tilde (~) means the voltage was fluctuating a lot, so the value is an average. Nothing was fluctuating more than a few tenths of a volt, though.
If I'm audio probing this, at what point should I expect to encounter an octave down? Is it after the flip-flops or after the JFET? I read through Valve Wizards description of how the circuit works, so I'm thinking the latter, maybe? Anything else I can check with the probe?
PS -- I Have also tried the 10M resistor from pin 5 to pin 8 of the 5532, it made no discernable difference.