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Bill, Thanks for the advice on the delta loop. The original Delta loop
information claimed that a corner fed *inverted* delta with 2 wooden supports
was able to produce a better vertical lobe and thus a better DX antenna. It
sort of mental conditioning, with a standard delta for 1.8 with 170 feet of
wire (33 percent) a few feet above ground, it would appear that a "whole lot
of cloud warming" is going on. One might infer that significant magic occurs
by taking a "poor antenna" inverted vee and merely running a wire from one
near ground end to the near ground end other. Yet the Q is reduced, the
efficiency improved, some losses mitigated, noise is reduced somewhat, and
things start to happen in the DX department. If I can think of the Delta's
horizontal wire as the ground system and the two sloping parts as in phase
semi verticals with the high current portions about 3/8 wave apart creating
some broadside directivity, is this what is going on here?
Herb
P.S. Your latter sentence is correct. The "squashed" Delta (~145' per
vertical leg and ~250' for the horizontal leg) yields optimum gain. Feed
1/4 wave from the top using 1/4 wave 75 ohm matching section to match the
~110 ohms to 50 ohms. This has been covered previously in the archives!
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