> Thanks Tom for the clear "balanced vs. unbalanced" treatise. I had
> planned to ask questions about shielded Flags on down the log, but
> decided to it now, while the iron is hot. The Little Gunn desperately
> needs a 160M receiving antenna breakthrough now, for use on a
> subdivision lot.
I don't understand why we would want to shield an antenna.
By definition, we can't shield an antenna for "bad signals" like
noise or it won't hear any "good signals" like DX. Noise from
undesired or unintentional transmitters is just another EM field that
propagates and affects antennas exactly like "good waves" radiated
from intentional or desired transmitters.
We can't "shield" an antenna and filter noise from desired signals,
nor will shielding reduce "noise coupling" to surrounding structures
any differently than it will affect desired signal coupling. Noise is
exactly like a signal so far as an antenna is concerned.
73, Tom W8JI
W8JI@contesting.com
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