Last week the Thonk kit came and I finally had some time over the weekend to start looking at it. First thing was the 4027 board. I pulled out the fancy trannies and put in the Thonk ones. The 4027 was still dead. About this time I started really freaking out. How could something with barely any parts not work! It couldn't be a resistor or cap.... oh wait, maybe the 3906/3904 is bad! I pulled them out and dropped in 2 new ones. There it was! Bummed that I sacrificed some of the rare parts, but, good to know the UT stuff wasn't bad. Keeping this in mind, I pulled out the 3904's in the VCO 2 circuit that's part of the Tri/Sine wave. Again, problem solved!
One last thing was the filter cutoff would raise the pitch of the VCO's as I would raise the cutoff. Another headpounder which ended up being that a keyboard CV needed to be applied. I know that it's mentioned to add a jumper to short the CV to ground, but that didn't change the issue.
To Do is add the reverb tank (which is on order) and add the 2 speakers, which I'll do eventually but it's not a priority for sure. Lastely I'd like to add a MIDI 2 CV internally. Right now I'm using my Kenton Pro Solo, which works great because it can send the gate and trigger needed for the envelopes to fire. I have a midimplant I could add, but I'd need to make a gate to trigger converter. Not hard, just not wanting to do that at the moment.
Below is a quick video of the first patch. It's annoying and ear piercing and sounds like a Tron junkyard bike race, but, it was fun to patch and mess with nonetheless. Soon I'll put together a proper demo.
As for building these: I'll do it, but the availability of future batches is really up in the air. There were some serious issues with the logistics company. They damaged a large amount of the cases and panels (mine being one of them). I know the issue has since been addressed and corrected, but there has not been any word of a new batch being processed. We shall wait and see.