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Old 05-17-2019, 07:55 AM
OldTimer OldTimer is offline
Junior Member
Join Date: Oct 2014
Location: The Netherlands
Posts: 10
Thank you for your help, much appreciated! And I don't mind at all if you assume I know nothing, because I can only learn from that, and I indeed don't know much about electronics (yet) :-)

So. Did as you described, and found the following behavior:
Voltage diff between base and emitter starts at around .4 volts, then it has this cycle of jumping up and then stabilizing for a moment, then jumping up further. Have tried that with 500K resistor, 1M resistor, with 1.5M, but all yield the same results. I've stopped each time I reached 1.7 volts across base/emitter, because that's when I can smell the transistor heat.

Will try with higher resistor still, and come back with that. Is the stabilizing/jumping higher behavior something you recognize by any chance?

As for the turns: it stated 2x 100 turns bifilar around a 32mm pvc pipe in the drawings, which is what I did and what you see in the pic (about 10cm/4inches of coil). I have no objections to increasing the wire length/number of turns, I just thought I'd start with as much of an exact copy of the circuit as I can.

Kind regards,
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