You’re welcome Michael, I’m glad I can help !

    Hi Bbarry,

    So I constructed the 2 circuits and everything works as described in the manual.
    Could it be possible that your light bulb is not the correct one ?

    There’s always a possibility to open the boxes and replace the transistors. Use a sharp cutter to cut between the top and case.

    I hope this is not needed.
    Can you build an oscillator circuit to check the transistors ?

    Have you read my forum posts ?

    I always explain that we need a protective resistor in series with the lamp. This is a basic rule for experimenting and will save the delicate transistors.

    Here the 2 circuits with protective resistors.

    The BE junction is always delicate so please be attentive when experimenting.

    Keep us informed !

    Circuit 1Circuit 2

    • This reply was modified 4 years ago by LectronFan.