In a message dated 15.11.99 12:37:27 Pacific Standard Time, K7GCO writes:
For those who can't imagine long runs of open wire line or the simplicity
of using one 135' dipole on all bands:
Runs up to 1500' long are practical due to the low loss. It allows
antennas at locations like on a hill without moving the shack. You need to
broaden your horizons of new, old and different techniques.
Why is an antenna that is far away so unusual if the feedline losses
are low, cheap and there are physical reasons to do so? LW and rhombic
antennas are long and frequently terminated at the end. What's the
difference of just running open wire line to that point on short poles (like
a Beverage) and connected to an antenna that radiates it all if there is a
radiation advantage to do so? It's been done for years by many. Both took
the same amount of distance. The latter took one pole for the antenna and
the feedline was supported on short poles to get there. The rhombic took 4
big poles to get there. A rhombic is a wide and long transmission line that
radiates to get to a termination resistor and waste 40% of the power to
eliminate the back lobe. Sometimes open wire lines are run to the other end
for pattern reversing purposes. It works and I will have 1 or 2 of them at a
very low retirement cost.
Long live open wire line.
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