1. Four relay switched vertical wires at the center bottom voltage node.
The antenna has about a 25 KHz 2:1 bandwidth so a "binary" ladder of 4
wires can cover the whole band if the natural loop is resonant at about
2Mhz. Of course, the wires are not 8:4:2:1 in ratio, so I've been trying
a lot of length combinations to get full, no gap coverage and have a
compromise set that "works". I've also got a continuous tuning
controller scoped out to sequence the relays.
I would not load at a voltage maximum.
I would series load at the feedpoint, where voltage is reasonable. A series
inductor system would work, or series capacitors to move it up, or both to
move it around. The nice thing about this is the relay feed could share the
same choke balun cores by taping the cable to the shield of the coaxial
feedline.
I'm not sure how a low apex height vertically polarized delta antenna would
work. I suspect not nearly as well as an inverted L or T with modest ground
system.
73 Tom
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Topband reflector - topband@contesting.com
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