W8JI wrote:
>The same effect will occur in a shunt fed tower's drop lead.
If we add a second conductor spaced well away from the
first, the unit-length inductance is reduced anv BW is
increased. At the same time voltage across the capacitor is
reduced, and bandwidth is increased.
Tom, very timely info since I've been considering
adding a second wire to my system. Bandwidth was not
a problem with a single #12 wire feeding my 180' tower,
but when I added parasitic dir/ref elements, 2:1 BW
decreased from about 70 kHz to about 30 kHz. I was
considering a 3-wire cage but had wondered if a 2-wire
system might work just as well with the flat part
facing the tower. What if any difference does wire
orientation make? Or am I wasting my time because of
the narrowing effect of the parasitic elements? The
other alternative I have is a motor drive on the
shunt capacitor since I've been manually changing it
to shift resonance when necessary (mainly contests).
73, Bill W4ZV
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|