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To All from PA0SE
Many thanks to those who gave me their views on the matter of FETs
versus bipolar transistors in LF transmitters.
I now understand why at unpredictable moments one of the four
HEXFETs IRF520 in my TX fails, though they are operated within their maximum
ratings. It must be the class B operation for which the FETs were not
designed.
I will turn down the supply voltage down to 30V again at which I
started on LF. The FETs seemed to accept that over prolonged transmission
times.
73, Dick, PA0SE
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