clifto writes:

Golf wrote:
I did a similiar test. Only without light bulb. Properly biased the
trans. It worked. Removed the base voltage, and it still conducted
with the same forward voltage across the emitter and collector. My
conclusion, since I can't turn off the transistor by removing base
voltage, it's shot.

I always feel safer shorting base to emitter to shut off a BJT.

That B-E resistor really should be low enough to do that.

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