Hi, Well I did it and it heats up a lot at 60 Hz....... This gapped core was a high-frequency one. Maybe that's why although I doubt it.
I tried it at 50KHz with a 555 timer. It doesn't heat.
Approximately:
I have .5 ohm and .23mH on the primary (28 turns) and
2.8 ohms and 28 mH on the secondary (330 turns).
The primary pumps 20 Watts at 4 volts. But I don't read a significant voltage on the secondary.
This seems consistent with Np/Ns= sqrt(Lp/Ls)
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