ADSR threads

koenpepping · Joined: Jun 25, 2014 Posts: 8 Location: utrecht NL

Hi,

First of all thanks for the designs.
I've built the noise gen, sample and hold and some mixers they work great!

Now I have build the ADSR envelope generator, but the sustain is always full 10v. (so i don't know if the decay is working). attack and release work fine inverted works also.

also the led isn't working (i measure 0.5v without gate, and 0.7v with gate), changed r22 to 470r doesn't work voltage stays the same. (led works fine on a battery btw)

I tried this:

replace the tl074 and 7555 by new ones
checked the wiring multiple times
measured connections and paths
checked all components on value
ic's aren't heating

nothing solved the problem so far.. any idea, tips or suggestions?

thanks already!

capicoso · Joined: Nov 19, 2012 Posts: 127 Location: Argentina

If you built new version, -i think it's not fixed in the pcb drawing yet-, to fix the led: the diode before the led is backwards, so take it off and put it the other way around.

koenpepping · Joined: Jun 25, 2014 Posts: 8 Location: utrecht NL

koenpepping · Joined: Jun 25, 2014 Posts: 8 Location: utrecht NL

I turned the attack, sustain and release to 0%. the decay was set to +-50%
and the decay started to work. after the doing that it works perfect!

changing the diode worked perfect.

it looks totally nice on my scope but I still don't have an vca/vco/filter or something to control with my envelope generator so thats my next project!

Thanks!