First, I'll assume that you have a transformer with separate primary and
secondary windings, with separate grounds. This provides common-mode
isolation between antenna and feedline.
Re-radiation from the feedline into the RX antenna is another matter. If
your feedline is buried, it's shielded by the earth and all is well. If the
feedline is elevated above ground it is an efficient receive antenna and can
contribute significant re-radiation.
In between is your feedline lying on the ground. Here in the agricultural
Midwest, on-ground is nearly as good as buried. I suspect it's different in
the desert and other low-conductivity locations. I usually drop two
Beverages off their support posts when I am not active, to keep the deer
from getting tangled in them. These two are insulated wire, so I can use
them as BoG. On bare or rough cultivated ground, the signal strength is 20+
dB lower than the normal 36-in. height. It takes extra preamp gain, but they
work OK as BoG. When these antennas are Beverage-on-snow (BoS) or draped
across corn stubble (BoCS), signal levels are noticeably higher than BoG.
Even a small height makes a difference, so I recommend keeping those
feedlines buried or smack dab on the ground.
73, Gary
K9AY
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