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 4 years, 8 months ago by Michael.