Hey guys, looking for your recommendations on schematics or PCB for a cv clock divider/multiplier. After a quick search I’ve seen some decent commercial solutions as well as some nice DIY.
This guys module is arduino-based and pretty badass but is pretty overkill for what I’m trying to do. https://youtu.be/pWMr9-NZZ2c
Kristian Blåsol has a fairly minimalist divider here:
This is great! I’ve watched some of his other vids before. Nice he shows all the plans he didn’t end up building as well
This one is pretty easy to build too. I made a strip board version for my EuroRack by substituting the 40106 (clock source) for an input jack and all the useful outputs (2-9&12-15) to the divided outputs. Actually not all of them-you get up to about a 1 every 256 here IIRC, which isn’t musically very useful for me.
(Edit: Oopsie-I meant to put a link in. At least it sounded like I was +1ing what @Dud said! Here’s where I meant to send you:
Hmmm. I think I’m missing something.
I really want a clock divider. And I was going to build Kristian’s…but didn’t like how it was inverting. I saw he referenced the one @Dud built but I only have 2n2904’s and BC547’s on hand not the BC550’s called for in that schematic. Well, those three are all close enough in spec for this they’re probably interchangeable I figure and I have a LOT more 2904’s than 547’s so … I broke out the breadboard to test. Wired up the clock input, 1/1 out and 1 divided out (which for now I have on the 1/8 pin)
And it seems to work. But…either I’m confused or misunderstanding something because it DOES seem to be inverting like Kristian’s even though the write up on this one specifically says it doesn’t invert and it doesn’t have the inverting op-amp on the input that Kristian’s does
Quick video of my test circuit:
It’s highly likely I’m just confused. I mean…in the video I say it’s setup for 1:4 but…it’s actually wired for 1:8 so obviously I’m at least a little confused 
I don’t show it in the video but I did try the 1:4 and 1:2 outputs as well. Maybe my brain just got mixed up because 1:2 was basically an inversion of 1:1…I think it will make more sense when I see multiple outputs going at once.
So…I’ll go ahead and do a stripboard and panel for it and see how it goes since it seems to be at least working.
It should be non inverting. And the divided output changes state when the 1/1 LED turns on (not off), so that’s all right.
Is there any chance your LFO LED is inverted?
You know what…it appears that it is. I hadn’t really noticed that before but now that you mention it I watched/listened more closely and realized that it is. And that explains a few other things that have seemed reversed to me. I’ll have to take a closer look at the LFO circuit in the morning.
I’m not very impressed with this LFO overall (it’s the mysterious “Roland 100m” that’s easy to find as a stripboard layout but has no real resemblance to an actual Roland 100m schematic) and have been debating messing with it to try and improve it vs. just building a better one already. I’m loving the LMNK VCLFO I got built the other night but it’s almost too much … maybe I need to find a “just right” LFO circuit I’m happier with next.
Got the clock in and 3 outputs drawn up on stripboard but time for me to call it a night. Will have to tackle the rest tomorrow. And it’s going to get tricky and/or ugly to fit it on the board I have available…but I think I’m ready for the challenge.
Ever make any headway on this? I’m looking for a clock divider and it would be amazing to find one with an LFO built in.
I did finish the clock divider, details here: My first DIY modules - starting a Kosmo format build
It works well, but for some reason the /8 output keeps flaking out on me and I can’t figure out why. Initially there was a small solder bridge and it came back after I cleared that up. Then a few days later it stopped working entirely. I swapped out the transistor on that line and it came back but then a few days later it was out again. So I’m not sure what’s happening. I’ve traced the circuit several dozen times but can’t find a problem. Could just be a couple of bad transistors…they’re from a cheap box of 200 I got for like $5 or something…but seems like there’s probably something still off. Maybe I damaged the IC when I had that bridge.
And there’s no LFO built in…and I’m not very happy with the LFO I built. I love the LMNC 1145 LFO - but it’s kind of overkill for what I want from a LFO. But I’m still debating what other LFO to build next. Now that I have a system for making my own PCB’s working fairly reliably it opens up a few more options for me and lets me stop dealing with quite so much stripboard 
I am in the same boat. I love the LMNC VCLFO, but the thing is a beast and it seems like overkill to use it just to run a sequencer.
It’s a shame to waste an LFO on clock duty. The Gate Grinder has a clock output, but at 10 cm wide it kind of needs to be something you use for its other functionality too. There aren’t that many simple DIY clock modules, most of them have an Arduino or something giving lots of other features. But a simple 555 based circuit is enough to run a sequencer.
For a simple clock, you can’t beat the 555.
A nice simple LFO (from looking at the schematics…) is the Syinsi one.
A TL074, some passives, a pot, Square/Triangle/Sine outputs.
You could put two of them in a 25mm module.
You can also get away with using an lmnc EG on loop mode if you mess with the settings
Which reminds me, I need a gate to trigger setup
Hmm. Following as I’m def in need of a clock divider.
This will definitely be one of the next modules I will build!
I have a clock divider that is 90% done. One small problem:
The 1/2 has shifted down into the 1/4 position and so on. So I lost 1/32 and I have a dead output in the middle. This is based on the Fonik divider
this makes me laugh every time.
And my take on it…with eurorack power and outputs brought out to headers instead of randomly located across the board and including all divisions possible instead of stopping at /64:
Just the cuts:
3D printable panel files and diylc source for the stripboard in my git: https://github.com/jhitesma/Modular-Synth-Build/tree/main/Clock%20Divider
Other than my flaky /8 I’ve been very happy with it…and that’s almost certainly my own fault for an initial missing cut and a solder bridge.
