Hi Gunther,

You continue to amaze me with these Lectron kits.

Great info !
From the schematic, I see that the triggering is somewhat different.
They had to use another transistor as amplifier and used a diode rectifier for the AC audio signal.

With the improved amplifier, the signal is so strong (about 3V pp) that it can be used as a trigger for the Schmitt trigger.
I like the approach of the Lectron kit as well !

Maybe the published circuit can be adapted to this approach !

I will let you know,


  • This reply was modified 2 years, 7 months ago by Michael.