----------- W4DLZ said:
I keep seeing reference to a half sloper..for a transmitt antenna...
I assume this is a 66 Ft sloping wire with a loading coil near the top
after the feed point...
-----------
A "full" sloper would usually refer to a half-wave center fed dipole
with one end supported near the top of a tower and the other run down
near to ground. Four of these around a tower at 90 degree intervals,
with only one fed at a time, was a mildly directional array popular in
the 60's and 70's. So a "full" sloper on 160 would be something over
250'
The half-sloper is a quarter wave pulled away and down, with various
feed arrangements in practice. The conductor will be 125' plus on
160m. If a loading coil is used, the length and the coil would still
be chosen to behave like a quarter wave. 66 feet would be an arbitrary
chosen length for a shortened quarter wave.
Due to the serious susceptibility of this antenna to tower details,
other vertical conductors in proximity and feed/matching details
rarely captured in models, this class of antenna has earned a
well-deserved reputation for wildly unpredictable results varying all
the way from "great" to "a dummy load."
This would apply to both transmitting and receiving performance due to
the uncertainty of the pattern.
73, Guy.
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