Topband: poor antenna- big dx ?

[Herb Schoenbohm]

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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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