Time for another annotated stripboard, this time Sam’s Simple DIY Envelope Generator:
The trigger to gate stage confused me a bit; see discussion here.
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Much to my shame but I’ll ask a stupid question.
Does the ground from the jack sockets connect to the ground of the power supply?
Built this circuit, on power up the supply gets very hot quite quickly.
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All grounds should be connected to each other and to the ground (0 V) from the supply. You want all parts of the system to agree on where 0 V is.
If your supply gets hot with only this module plugged in something’s wrong; this uses very little current.
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This will absolutely save me the next time i build this. I had to fiddle about with it a bit.
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I’m a bit late to the party on this one but quick question: is the 10nf capacitor electrolytic, poly, ceramic?
Thanks!
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Ceramic works, but maybe film are better ?
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You’d have a bit of trouble finding a 10 nF electrolytic. Mostly they tend to be above 100 nF.
I’d probably use film, but as @Dud says, ceramic should be good.
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Thanks both. I had thought that it would be small for an electrolytic but only the 1uf had been called out specifically as non-polarised. Appreciate the help 
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Based on a conversation in a separate thread with @analogoutput, it might be worth adding in a pulldown resistor on the output. The output sits at around -2v for me without one, but adding in a resistor to ground (I used 1M, but 100K suggested too) keeps it sat at 0v until the envelope is triggered.
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As mentioned here, R9 and D7 after R8 creates a voltage divider that reduces the maximum amplitude at the output to something like 6 V, which may not be enough to fully open some VCAs or VCFs. I think most Eurorack EGs put out something more like 8 to 10 V. If you move R9 and D7 to before R8 then the maximum output should be in something more like the 9 V range.
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The LED if positioned after the 1k output resistor also alters the shape of the envelope as seen in this simulation. Blue is with the LED after the output resistor and green is with the LED before it (with a voltage divider added to scale it to about the same amplitude for comparison). There’s also a 100k pulldown added before the output resistor in both cases.
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