I was wondering if there is any chance to you making another batch of boards again? 1) it's a lot more work than it looks :-) 2) I wouldn't want to do exactly the same board run, there are some additional mods I'd make, including the possibility of doing it as SMD 3) There are a few other options o...

I have too many things already on my plate to offer to make them, but cables with a dotcom header on on one end and an MOTM or Modcan on the other should work just fine with the dotcom power supply (I don't have specific experience with Modcan, but I just looked it up and it's supposed to be bipolar...

We probably could dig in and swap chips and eliminate the odd double-press for the Klee to load the first time, but it'd be a lot of work for "fixing" what's ultimately a working module. So I think adding the double-press to the warm-up routine for your system may be the less anxiety-inducing appro...

Try with a cable plugged in somewhere else.

That kinda sounds like a dicey ground somewhere, which is strengthened by having ground coming in from another module over the cable.

The fact of IC's having flat pins and not round ones is the main explanation both for "not fitting as well" and for the heated difference of opinion. That's part of why I qualified my own :) Edit: I suppose it is possible that there are high quality leaf spring sockets out there -- I just can't say ...

Machine pin (round) chip sockets are higher quality than the leaf spring types. Particularly if you are removing and re-inserting. I have done repairs on PCBs with the leaf spring types where the spring was pushed in, and not actually making contact with the chips. I've also done repairs once where ...

I would definitely look at your solder joints directly for evidence of cold solders, as you've correctly identified.

Did you start with page 93 of the build guide (the original) where it talks about checking for power shorts and power to all the various chips? Power is the first thing to check, almost always. When you power on, do any of the step LEDs light? Or are they always off? It's not uncommon for the Klee t...

Aren't the gate levels settable with the trimmers now?

That would be safer than having a random clamping cable around that could be fitted backwards.

So I'm going to take it that since it appears that the LM301 is at fault, I'm not going to do those measurements :-D Looks that way for now. I shall be experimenting with an SMT LM201 shortly, along with a few other changes for a forthcoming Rev 7. They way things are going, it’ll end up being enti...

Thanks - rotation tag or not doesn't matter, but there are "fake" Alpha pots that look fairly similar to the Thonk ones but have a slightly larger shaft diameter. I've tried before, unsuccessully, to fit them through Random Source panels. I would recommend getting one of these https://www.harborfre...

So I'm going to take it that since it appears that the LM301 is at fault, I'm not going to do those measurements :-D

I apologize, it's been a long day, I haven't forgotten you but I have no steam left. I will try to do the promised measurements tomorrow.

One other question: how does the unquantized output look? Aside from being higher voltages, of course.

I got my kit from Synth Cube - PCB revision V6a - and all IC's are matched with part numbers on the Synthcube BOM 1.6.1. Good to see I'm not crazy about TP4 - So you verified that the sawtooth wave is clipped at the top and offset by around +7V yes indeed it is.... Solder joints look good on all fa...

One other thing -- have you already calibrated, or are you trying to troubleshoot first? I've found with these there are times when stuff isn't working, but starts doing so once it's calibrated. Most commonly I've seen that with the clock speed (before calibration, lowest clock speed doesn't run the...

The TP4 thing is "normal". I have a note in my copy of the service manual that it has about 7 / 7.5V offset from what is shown and the one I have in front of me shows the same behavior but works 100%. Kind of wonder if It's not a mistake in the manual. The thing about the quantizer though, that's we...

I see Ian responded on the other thread, so ... that would be the thing then.

The teezer had some revisions after the beta builds. I'm not sure if the docs got updated with the revised layout. My "day job" work day is under way, but I will try to dig out my beta PCB and my final PCB and compare them to what you're showing later ....

Very nice arthurdent

I've been kinda quiet this year, but figured I should throw one quick thing under the door as it's closing. I've had these rails kicking around for ages, but they were on metal side panels, which only really allowed "front & back" and I didn't really go for that. Last night I realized nothing stoppe...

Exploding Shed has a tool for the knurled nuts.

Yeah the instructions on this point were not great. I figured it out by looking at the CGS/Elby instructions for the same module.

WOW!

Look at where -7V connects. The zener is actually a 5.1V, so the -7V is -12V + 5V = -7V. The place I see it is feeding U2 & U3 (LM311) power pins, but those are actual loads, not just dead to ground or anything, so that's what's limiting the current. I would imagine the reason it's a + voltage now i...