As Tony AD0VC pointed out, the commutating diode across L14 is definitely a good idea regardless ?of which FET you use. The TN0106 produces a much higher spike voltage than the BS170 because it’s turned on much harder. For some reason, the BS170 isn’t very tolerant of voltages exceeding the 60V breakdown voltage while the TN/VN devices seem to be able to tolerate a lot more. Still, the data sheet specs should be strictly honored regardless of what others are reporting.
My suggestion of alternative FETs is to improve reliability. The additional power output is a pleasant side effect.
This is interesting, Tony. I'm gonna have to study the schematic to determine the direction of the diode. I think I read of this solution in another post.?
For now...I live in the far SE corner of GA, and we are preparing for the arrival of Idalia. Ooph! I can't wait for this to get over with...
