I love this build. It’s like the lovechild of Jan Ostman and Dave from Notes & Volts. Bravo @Synthlurker !
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Welcome! Great job. How many did you make?
How varied are the audible effects?
Post a pic and maybe a recording when you can.
Crack on!
I posted about it on Twitter - it has the original circuit diagram I found on Modwiggler, some build pics, and a video of the quad LPG in action!
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Perfect timing! Where would i find the schematic?
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I had transcribed the schem from the simulation’s site
it’s here on my blog 
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Et une autre contribution solide et fiable. Merci encore, vous êtes une star!
In @Dud we trust!
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Greetings everyone! Long time lurker, first time posting 
Gotta say, this community has been super helpful in my Synth DIY journey. I’m very impatient, so having some stripboard layouts to complete while I work on my own knowledge of electronics has been super helpful in keeping me invested in the hobby.
Here I have a simple stripboard layout of the transistor VCA schematic from @moritzklein . I didn’t worry about adding a gain knob or anything, just kept it basic. I’ve been having a hard time finding VCA layouts that work for me (pretty sure my LM13700s are counterfeit) so getting this one to work on the first try was good enough for me!
Let me know if any of you see anything I could improve on! This is my very first stripboard layout, so I’m sure it could be better.
Thanks!
EDIT: Had an incorrect resistor highlighted, so I corrected it
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Regulated power supply suitable for guitar effects and 9V modules. As usual, make sure to use a suitable DC wall-wart at the input and attach heatsink to the voltage regulator.
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forgive my ignorance, but what sort of fuse do you use?
It’s supposed to be a glass fuse that will blow if the circuit draws more current than either the wall-wart or the regulator can handle, so it should be rated at 500mA-1A depending on the wall-wart. I used an axial (pigtail) glass fuse, but if you make the distance/pitch on the stripboard a couple of columns longer, then you can install a fuseholder to insert the fuse.
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Nice one! Thanks for the info!
This is a good schematic. It’s pretty much the same as juanito Moore’s vca. I built off juanitos schematic and the dual circuits both work nice!
Forgive my ignorance as well, but what I understand to be a diode, noted in blue on D,C and F,C, with the two little arrows…I’ve never seen that before, and I see a diode notated somewhere else very clearly. Can someone please explain?
I believe that’s a LED, so yes, it’s a diode and I think the two little arrows are meant to be rays of light.
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I am slapping myself, of course, thank you @jaradical !!
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Yes, it’s an LED. The component image was not clear enough to indicate the cathode, so I used the schematic notation instead. The LED will light to indicate that there is power and, in addition, provide a light load so as not to damage the wallwart (apparently wallwarts don’t like to work without any load attached to them).
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I’d always heard it’s negative regulators that want to have a load, and without it it won’t regulate, though it won’t be damaged. From http://musicfromouterspace.com/analogsynth_new/WALLWARTSUPPLY/WALLWARTSUPPLY.php:
The load resistors were added as a convenience for testing without a load and are not necessary. The negative regulator needs a slight load to begin regulating which is normally provided by the circuit being powered. These resistors provide a small load so the output voltage can be observed prior to connecting the supply to your circuit.
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If my wall-wart is rated 700mA, and after calculating my total current draw shouldn’t ever be over 500mA, would a 670mA glass fuse be sufficient? Having difficulties finding one that isn’t 2A
seems like this would be sufficient https://www.digikey.com/en/products/detail/bel-fuse-inc/5MFP-700-R/1010076