So… weird one… I’ve built the MIAW dual VCA based from @juggles stripboard layout…
Tested using my LFO to the CV in at a very slow rate, this seemed to work OK opening and closing with the square out of the LFO
Took the LFO out of the loop and hooked up the CV in to the keysteps gate output…
Odd thing is when connected to the Keystep.
I press a key - VCA closes audio stops.
Release the key VCA opens and continuous note from the VCO…
Has anyone experienced this?
I’ve checked the keystep config in the PC Spftware for the keystep and tested both settings (V-Trig 5v and V-Trig 12v) for the gate output.
In order to test the output I connected a LED direct to the gate output with it set to 5V and it operates as expected (keypress lights LED, release turns off LED)
strange, it looks like your VCA is working backwards, here is the diagram if that can help you
check if you don’t have a mistake on the Op Amp input (+/-), this can invert the signal
i don’t really understand, you use the LFO and the Keytstep ?
You can use the LFO loop or the Keytstep gate out to trigger the VCA CV in .
Sorry that’s my poor choice of words.
By taking it out of the loop I meant unplugging it.
VCO - VCA - (CV = LFO) appears to work (may still be inverted)
VCO - VCA - (CV = Keystep) is definitely inverted (Key press closes VCA)
I believe I did warn that it’s not a very good VCA 
(Much like MIAW where I got it from warned.)
At the time I built mine I didn’t have anything that generated gates I could test with so I had also just used an LFO.
I just tested it with my keystep…and yeah…with the bias dead in the middle it almost works as expected - but it never fully mutes the signal so it just goes gets louder when I hit a key to send a gate.
But at any other point on the bias it works inverted.
So…it’s not you.
But I’m not sure if it’s my stripboard layout or Kristian’s original circuit I based it on. I’ll try and take a look at it later tonight and figure out which of us the blame falls on.
That’s odd I quite liked Christian’s vca day. Do keep us posted.
OK so I half fixed the issue…
Managed to stop the inverting by tying the 4.7k Resistor to ground rather than -12V.
This gives the correct operation of the gate closing when key is released.
However the issue with the gate not working unless the pot is in the middle (and not fully closing the VCA) is still there
OK so I’m just having a look.
Looks like there’s maybe some missing circuitry and the initial idea “MAY” have been based on this
Please excuse the amount of tabs open in chrome
Hmm…looking at my stripboard layout and the schematic Kristian provided…it looks they both have the 4.7k resistors going to -12 so that at least isn’t on me
I seem to remember in his video he mentioned that the VCA never really closed well and tended to bleed a lot of signal. In fact I got the impression from the video that he didn’t really recommend building this one…but I did anyway because it was simple and I had the parts on hand so even if it didn’t work well it would be better than nothing and I was able to toss it together in an evening.
Shortly after I made it I got my LMNC 1183 quad VCA and honestly haven’t touched this module since until I tested it today.
I probably never noticed it working inverted before because I only used it with an LFO and didn’t notice if it was triggering on the positive or negative.
I had built it, but it was not inverted, just not very good, big “clic” at triggering and yes not a real silence between, i talked about it here
Nothing against Kristian B , he make many good things, but not this one (for me 
)
Ahh… ill breadboard it out tomorrow and see if I can get something a little better working 
- I’ve already printed the panel so I’m not going to let this beat me 
or …
I built Niklas Rönnberg’s 4 times, and I recommend it more, it’s simple and easy to build but efficient, other here had build it too.
