I could give it a go, but at my current pace and style I’ll have invented a new construction method by next August and will be waiting for a supply of wool with which to knit the front panel. After I learn to knit. After I design the front panel. After I learn how to solder conductive spaghetti.
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VC knitting machine with a Jacquard/cnc like sequencer might round that off nicely. Have fun.
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Searching further I found a stripboard layout for the Thomas Henry 555 VCO which the designer confirms has been tested. It’s a fairly simple if capable design. Henry himself described it as his attempt to approximate the CEM3340 chip using easily available parts. That it is, comprising only 555, a couple of TL074 quad op amps and an LM13700, and what looks like the contents of a keen DIY synth hobbyist’s back pocket. Nothing unusual or frightening.
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Be carrefull it’s on the same page i found the Barton Wave Animator stripboard with a lot of errors
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Apparently the success of the Thomas Henry design depends a lot on having the right type of 555. This is much discussed on the thread. I’m old enough to remember when there was only one type of 555, and naive enough to wonder why it was deemed necessary to produce new chips with the same numeric designation.
Looking at the discussion ought to be enough to convince anyone of the wisdom of using monolithic VCO chips like the 3340 for serious tone generation.
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Which made sense back when 3340 wasn’t produced by anyone, but makes less sense today when there’s multiple sources…
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Part of the reason for continued interest in the Thomas Henry designs may be reverence for the name. He was producing and generously distributing module designs at a time when there was comparatively little on the market to match the demand of hobbyists, so the name became a brand in a very organic way.
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Throwing one more on the pile, the 4093/NAND Synth.
Sounds like shit and there’s only a kit PCB and no perfboard schematic, but here ya go anyway:
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Seeing the royal game of ur be chopped up made me sad.
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One more, kind of an interesting one. The AD9833 Programmable Waveform Generator.
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a vid with the AD9833
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This is a really simple circuit for 4x CV controlled square VCOs using a 40106.
http://castlerocktronics.com/modular/articles/CR-001_-_4xSQUARE.pdf
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Extremely simple square generator using the SN74HC14N, which costs between 13 and 30 cents:
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Technically I guess it’s a voltage controlled oscillator, though the voltage controls the amplitude, not the frequency.
If you want a very simple oscillator whose frequency is voltage controlled (V/Hz, not V/Oct) you can use a CD4046B phase locked loop chip.
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… and here the CV basically allows you to turn the oscillator on and off, which if you do it at audio frequency gets interesting. But again, it’s not VC of frequency at least in the usual sense.
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Ahhhhhhhhh, good eye! That still might be useful for pulsating drones without needing a bunch of VCAs.
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Here’s a v/oct mod for it. We’ve talked about this previously somewhere… https://www.youtube.com/watch?v=cLp_9nHhEEw
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In this thread 
All the step to make a VCO 1V/oct and more with a CD40106 chip
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KiCad files and Gerbers are here for a non 3340 VCO:
It appears to be nearly if not exactly identical to the MFOS VCO.
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that case is dope! sounds nasty too 