<p style=”text-align: justify;”>Hello Guenther,</p>
    Electronic circuits are sometimes mysterious, not ?

    Glad you took the time to build this experiment.
    Actually, this circuit is a thyristor.

    By closing the lower switch, we put a small voltage on the “gate” and activate the thyristor.

    By closing the upper switch, we are “opening” the feedback loop so the thyristor deactivates.

    A hint for the battery connection anomaly : check the grounding of the circuit 😉
    I will publish soon a version with 2 silicon transistors, the diagram will be clearer.


    Another question, Why is there a capacitor of 0,1uF in the circuit ?

    Will it still work without ?