Interesting - but hopefully a little less prone to noise from surrounding modules than the twin-T snares out there. I’ll give it a go when I have some time to build it. I might see if I can rearrange it into a single stripboard layout (if it’ll fit)
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The noise portion can definitely be added in a single strip board, if you are doing Kosmo format. I split that off to fit in my eurorack size module. I’d bet there is enough room to squeeze it down enough to get the gate to trigger on there, too.
For reference, the schematic sources: Low & High Toms – DIY Eurorack Synth Stuff
TR-606 CLONE 5U.pdf - Google Drive
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Hello there,
I’d like to have a go at making a stripboard layout, may I ask where the software comes from. I do like the idea of the numbers and letters at the sides.
Cheers
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Most likely to be DIY Layout Creator.
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Hi,
People here like to use DYI Layout Creator. And you can download it here.
Github DYI Layout Creator Download
This link is an official repository on Github
All the best.
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Thanks for the links both, good of you
Cheers
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I use StripboardCAD on the iPad, I like it, it’s very simplistic but more than enough for my needs (it also runs on macOS via the compatibility feature).
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Not sure why but I built ths and it didn’t work. LED stays solid and it fried my filter 
thankfully i had spare chips
A must! Loads of good mechanics, components and if it works? Bonus
(Why post in this thread?)
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This is an excellent question! As in real life, Not sure how I got here.
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Hey @Gwyniad , I’ve just built your clock with divisions and its working… sort of…
The range pot is having little to no effect on the rate of the clock, and only measures 0-0.05v over the whole throw of the pot.
The outputs seems to be dividing properly but are in the audio range, which without the pot functioning properly is probably normal.
One thing that I noticed looking at the schematic vs the stripboard layout is that the transistors are missing in the layout. Is this likely to be causing my issue?
I’m still very much a beginner, so my understanding of things is still somewhat limited. I’ve checked my board and the layout and everything is in the right place. I have enough understanding of things to be able to implement the transistor stage into the layout, but wanted to ask the question first.
Let me know what you think, I’m scratching my head on this one.
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No transistors! Oh, honestly, what am I like. Thanks for picking that up, I’m on hols at the moment and will fix this when I’m back. Sorry!
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The clock oscillator in the upper left of the schematic should not be affected by the transistors or their absence. If it actually oscillates but its rate doesn’t change when you change the pot, there’s a problem with or somewhere close to the pot. And there’s not much at all it could be — the clock is pretty simple and if it’s oscillating, it must be connected pretty close to properly. So I’d say either there’s an assembly problem with the pot — perhaps a solder bridge across it — or the pot is the wrong value, like 1k instead of 100k, if the rate is too fast. A too-small capacitor would make it run too fast, too, but the pot would work in that case.
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Thanks the reply. I have had a couple of different pots connected, both 100k so I’m assuming an issue with the board somewhere.
What exactly is the purpose of the transistors just out of curiosity.
I’ll have to go over the board and check for solder bridges/continuity. If the TL072 is a fake, then I assume it wouldn’t oscillate, which it does. I get a nice square wave on all outputs of about 5v. The divisions aren’t exact on the higher ones though. I’m about 100Hz shy on the 1/8th note and I think the 1/16th is slightly out too but can’t get a good read on my oscilloscope as I haven’t worked out to get it to show kHz. It’s a knock of of the JYE tech DSO138.
When I get home on Monday I’ll check over the board. It’s almost there and likely to be something simple.
As a point of curiosity as well, what voltage change should I expect to see over the range of the pot?
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It’s a variable resistor in the feedback of an op amp with an oscillating output, so a voltage measurement would not give you anything meaningful. But I think you should be able to do an in-circuit resistance measurement between op amp pins 1 and 2 and see that you’re getting a range of 10k to 110k. Or would the cap screw that up? Worth a try.
The incorrect frequencies are odd, the outputs ought to be in lock step synch with the input so should be exact divisions, but maybe fix the clock first.
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The two transistors act as an OR gate for the reset button and Q4 going into the reset of the 4024 so that either of these will trigger the reset without effecting each other. You could also swap them for a couple of diodes and a pull-down resistor like Jos suggested in the post after mine. Or even an actual OR gate IC. I just had some spare transistors and liked the idea of using them.
You were spot on. An in circuit measurement of resistance over pins 1 and 2 of the TL072 gives me 10k to 110k as expected. Likewise the pot gives me 0-100k measuring across its terminals so everything is ok with the pot. I’ll have to test a known good TL072 as this one is an AliEx special but given that it is oscillating I think it’s doing its job. I’ve taken a picture of the output of the opamp reading on my oscilloscope. Not sure if this is the waveform I should be seeing but this is what I have. I’ve done a quick and dirty test to see if there is continuity between the stripboard traces and so far nothing, but I do need to go over it thoroughly.
It might also be worth noting, which I didn’t think of before, that I’m running it on +/-15v not 12. I have the other 2 chips running on 5v as per the schematic, but the opamp is running on dual 15v.
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That says it’s a 66 Hz frequency and the period visible on the scope agrees with that, so it’s the right frequency ballpark. Technically audio frequency but at the low end. (With the pot centered you ought to get roughly 10 Hz, and around 50 Hz with the pot fully at the low resistance end.) The wave shape and voltage levels are strange, though. At the input to the following op amp buffer you should be getting a square wave. With ±12 V it would be ±5 V, with ±15 V it would be ±6.25 V, you have +5 V and about -1.5 V. So yes, looks like something’s messed up. If you measure 10k to 110k from pin 1 to pin 2, and it’s not responding to the pot, then there’s got to be something misconnected. Very strange. Can you post pictures of your build, both sides?
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Now things get complicated haha. I took the jack out that I had in to check the output of the opamp before the 4024. After putting it back in and not changing anything else I now get a 36hz signal with the pot fully clockwise and less than 2hz full CCW. Roughly 5-8 in the middle.
The frequency of the square waves coming out of the 74HC14 are still much the same although slightly lower than before. On the whole note I get a variance of 77-80 Hz.
Here are the pictures of my board. The extreme left has the voltage regulator to get the 5v supply as I don’t have a 5v rail running from my PSU. I hope you can see something that I can’t because it really has me scratching. All components were checked for value when going into the board so I’m confident they are correct.
Ignore the jack with the pink lead in it. That’s just the extra I put in to check the output of the opamp. Not a permanent fixture.
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I think this one might have defeated me. I’ve been over the layout vs my board (updated by Gwyniad to include the transistor stage) and my board vs the schematic and everything checks out in all 3. I’ve swapped the pot out for another one with no change, I’ve wired the pot every which way I can think of which for some reason I can pin down momentarily caused the output to drop to 8hz on the whole note but still with the same variance over the throw of the pot.
The only difference between my print and the layout/schematic is my 7805 stage to bring 5v to the board but I’ve checked over that and it’s completely isolated from the rest of the board and the right voltages are at the right pins of all the ICs.
I can’t see a reason why the pot isn’t changing the tempo of the clock or why the output is so fast in the first place.
On a side note I did work out that the outputs are all dividing properly, it was just that the scope couldn’t display them properly once they reached a certain point. I changed the time window and the correct frequencies were reading so at least that’s a win I guess.