Fritzing? Or KiCad? KiCad’s been very stable for me.
haha thank you I should take the time to look at all this! the guy is well dressed 
no it’s on fritzing when I start the automatic routing it crashes. I would have to install the new version but to make my pcb I will install KiCad if it’s better…
Take the time to follow the tutorials @BlackDeath has posted above.
Kicad is much more complex that Fritzing, but that’s because it can do way more things…
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OK yes it’s true that the circuit is quite complicated!
I asked for this circuit but it was in gereral. but in spite of that I would really need a VCO 1v/oct because all those I made based on the AS3340 were fried and in the end I had to burn 5 or 6 AS3340 and a good ten TL072. 
I love this guy. from zero experience I just followed along with his entire series on my own simple circuit (multiples) and I managed to get a working module with only like 15 mistakes 
. You just have to go for it and be ready for a little disappointment when you have to reprint your design twice
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A caveat is that those videos are a couple of years old and appear to be based on KiCad version 4. The current version is 5. These are the tutorials I used, based on version 5. They’re pretty good. But perhaps the DigiKey ones are better (I haven’t gone through them) and you could just skim these for updated information.
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That’s a good point, forgot there were a couple times I had to watch update vids (I learned on kicad5) but the core of the series holds up
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yes thanks for the links I’ll also look for a video in french that would make it easier for me to understand. 
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I have just made a new stripboard layout of the same dimensions but now the transistors and the Thermistor are close together and there are no more jump wires. It’s not verified yet but I’ve gone over and over it, checking for mistakes and I can’t find any. Here it is:
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I’ve put the new layout up on my website in three parts: wiring diagram, print only view and cuts only view. Again, it’s not verified but I’m confident it’s good. I’m going to build it myself soon to verify it.
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UPDATE: I have just completed the building of a second Thomas Henry VCO-555 using the new layout, so that I could verify it, and I’m happy to say it worked first time. If you put all the trimmers in the middle position before you solder them in, you will find that you don’t even need to adjust the sinewave trimmers 
It’s working perfectly. The one thing I wasn’t happy with was the limited range of the Pulse Width Modulation of the VCO so I changed resistor R47 from 330K to 190K and now PWM goes from 1% to 95%. The layouts are updated with the new value for R47.
All the details are on my website https://www.eddybergman.com
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Hi Eddy. Hope you doing well.
Trimming my 2nd TH. VCO555 module but im having trouble getting perfect round sine wave.
I followed the steps changing some resistors because im running +12,-12 and changed R27 from 39k to 22k. I also set both trimmers to their mid values and i expected a perfectly balanced sine wave. Well its not. Upper side is nice and round but the low half is more like triangle. I had better results with the 39k, but is it possible that i need a higher value for R27? A 47k maybe? Or do i need to look at something different?
This is with both trimmers set to their midpoints
This is when both trimmers are fully ccw
I think i need to change a resistor around the 100k trimmer. This trimmer is a little smaller so it has less turns (15), while the bigger ones have 25 or so. Dont know which resistor to replace to have more range for the less turns trimmer
Hmmm weird. Well if you have better results with the 39K over the 22K then I would try a 47K or 51K but it’s weird that this is necessary. I suppose you made sure your voltage rails are at +/-12V exactly? Also check the values of the resistors around that LM13700 opamp. There’s a 300K to +12V, a 390 Ohm from pin 13 to ground. You can also experiment with the 1M going from the wiper of the sine symmetry trimmer to pin 13. Take a 1M resistor and touch the resistor legs with it, putting it in parallel over the 1M and see if the shape of the sinewave changes.
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Hi Eddy
Thanks for your tips. Did not check the output of the Triangle wave. When this wave is not 50/50 the sine will be off too. Well, i guess im gonna have a testing day tomorrow. Thats what DIY is all about. Im sure i figure it out eventually.
Thanks
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Yes you need to set the triangle wave first before you get to the sinewave because the sine is made from the triangle. Good luck. I hope you find the cause.
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Hi
I now have better results. 39k resistor changed to 47k. Still the 22k trimmer all the way up. 100k trimmer all the way down. What i would like to achieve is to have more margins on both trimpots. Sine wave top still has a very small dent, and lower side is still a bit pointy, but with both trimmers at max i dont know what else i can do to get more headroom back on the trimmers so that i can get a better looking round sine wave.
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Still sounds like something is off. Some other resistor values maybe. Those trimmers shouldn’t need to be in their full throw positions. But if it works it works. 
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Hi
Turns out that I’ve had taken some photo’s from my first VCO555 a while ago while building it. Guess what: I did change resistor R27 (39k) to 22k, but I also changed the 25k trimpot for a 100k. Apparently this combination results in a more symmetrical Sine wave. So back to the soldering iron.
I hope someone will tap in and have ideas where to look at regarding the trimmers
Update:
I came across the VCO555 simulation in falstad.
Used these values.
Now i have a nice rounded sine, but only the top half. Lower half is still pointy like a triangle.
This is how my triangle looks like.
Looks ok to me (maybe small distortion on low half??)
Need to investigate this further. All other wave forms are looking good.
Update: a better looking sinewave
I reverted everything back to original. Only thing i changed was the R27 connected to pin 16. I used a 33k resistor and ive changed the 5.6k into a 2.7k resistor. Now im happy with the sinewave.
Moving up to the Pulse/Square wave. Ive changed the 330k into a 180k resistor and have more width now when modulating BUT, there’s always a but 
, when i turn my potentioneter all the way CCW it goes through zero. Flatlined. Thats nice, but when i turn it all the way up to the right (CW), its not going through zero. I see some amount of pulse there. Also. I dont have a 50/50 square wave when the pot is in middle position. How to fix this? Well. Ive read an article to use 1n4148 steering diode connected to pin7 , and for pin 6 another diode with both a 1k resistor. Does anyone have. Another solution or does this one work?
update: a litany of dumbassery has occurred.
I accidentally used a Logarithmic potentiometer instead. Duh.
Now I need to finetune it so when the PW potmeter is entered, that I get a nice 50/50 duty cycle.
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