> OK, I can visualize how this might work, but I'm missing a couple of
> steps. On a shunt fed tower, for example, where is the "drop wire"
> connected to the system? Is it tuned by changing the length, or by
> adding capacitance or inductance somewhere?
In general you want a modest length of drop wire, something that uses
a fairly large capacitor for tuning. The drop wire connects someplace
above the point where the system ties to the tower.
That keeps the Q low, and bandwidth wider. Multiple drops also have
more bandwidth, because they use larger C values for a given drop
wire length.
You adjust the capacitor's reactance to tune the system. In BC
systems we used a small variable L in series with a fixed
capacitor...but for amateur use a conventional air variable would
work just fine.
By the way, if anyone can e-mail me a file that shows severe or even
modest interaction of a K9AY antenna with a metal mast I'd appreciate
it. I'm stumped about why that would happen, and could not duplicate
that effect here. Maybe I just haven't hit the bad combination.
73, Tom W8JI
W8JI@contesting.com
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