[sdiy] AR envelope and 4066

[gabriel at lindeborg.org]

Hi Ryan!

You do realise that you by closing the 4066 switch and setting the Attack
to 0ohms will have a hefty current running thru the 4066 until the cap is
fully charged? Sort of like shortening the 15V to ground...

//Gabbe

> hi all,
>
> I've just buiit a simple AR or AD envelope generator. it's based on ray
> wilson's design, but now different. the schematic is here:
> http://www.sdiy.org/destrukto/temp/ad-ad_eg.pdf
>
> but, there is something terribly wrong with it. It works at first, but
> when I adjust the attack (and possibly decay) pot to 0ohm, the CD4066
> gets hot burns. I've blown 2 cd4066's already. Should I be limiting the
> current into the 4066? I've looked at a few designs that use a 4066 and
> one has 47ohm resistors in series with the attack/release pots, and the
> other does not.
>
> it is possible that there is a short somewhere on the board. I made it
> on a CNC milling machine and small bits of copper sometimes cause
> shorts. I have went over the whole board with an exacto knife and
> continuity tester, but still could have missed something.
>
> this was supposed to be a test board. I planned to have PCBs made if it
> worked out, but I can't say if the problem is with the design or the
> construction so I'm not sure what to do. any ideas on the design?
>
> -ryan
>