5 Comments

1. Mark Colan says:

   November 12, 2014 at 5:45 am

   Could you be more specific about the specs or type of Vactrol used in this circuit? Or is it simply that the characteristics of most available Vactrols are similar enough to be compatible with this circuit?

   thanks!

2. Steve Harmon says:

   November 14, 2014 at 11:35 am

   Hi Mark, since we have the trimmers, really most any optocoupler / Vactrol should work fine. Good question!

3. Mark Colan says:

   November 18, 2014 at 12:17 am

   Are they all likely to fit the PC board? Can you give parts numbers for a few easily obtainable types?

4. Raf says:

   November 28, 2014 at 6:54 am

   Hey Mark Colan!
   You can easily do your own DIY ”homebrew” vactrols!! Check this out :
   http://z11.invisionfree.com/BendModDIY/ar/t18.htm
   http://www.hard-core-dx.com/nordicdx/antenna/loop/k9ay/vactrol.html
   Google it!! Just be aware to avoid those transparents super-bright LEDs, it work best with regular colored ones, like red, green yellow. You can even had a nice ramp effect with a capacitor in parallel!! Nice day mate!!

5. Steve Harmon says:

   November 28, 2014 at 8:14 am

   True that, pretty easy and cheeep!