My Beverage uses a toroidal transformer with separate primary and secondary.
I ground the primary (antenna input)winding to a ground rod surrounded by
a mini radial system of about 10 radials about 15'long. After lightning
wiped out the transformer, I rewound it and placed it inside an plug-in coil
form, and unplug it when the ant is not in use, and so far, no more damage,
even during several nearby hits this summer.
The secondary is not grounded at the transformer end, but it is grounded at
the receiver end, to the station ground system, which is designed for both
rf and lightning. There are no chokes or ferrite installed along the
feedline.
I notice that with the transformer unplugged, I hear extremely weak signals,
almost completely buried in the background hiss. Of course, when I plug in
the transformer, the antenna comes alive. I assume that if the coax feeder
were picking up unwanted signal and noise, that it would still be present
with the transformer unplugged. I notice little, if any difference between
unplugging the transformer, and disconnecting the antenna with the
transformer plugged in. In any case, the signal pickup I get from the
feedline-less-antenna is too small to significantly degrade the performance
of the Beverage.
Don K4KYV
Does anyone disagree with the above assumption?
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