Hello Jeff and group,
maybe someone can pass this message on to F6BWO since I don't have his
email address (if he has internet access):
I was in contact with Jeff this morning at DK4U, and the QRM was
surprisingly low. F6BWO was 539 here (at DK4U).
The antenna impedance was very ununual too, and after half an hour, the
PA ran wild and finally the supply's current monitor tripped.
Not sure what exactly happened but looks like after many years of
reliable operation, one of the MOSFETs has blown.
Possibly the gate bias control didn't like the -2°C shack temperature ....
Hope to be QRV on LF again soon, with a more endurable FET than the
IRF540 (possibly a HUF75343, giving one or two dB's more output).
73,
Wolf DL4YHF .
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