>
>> I seem to also remember another post where someone (Tom perhaps? -
>> I don't
>> remember now) said they had talked with Orr about this
>> configuration and he
>> later agreed that perhaps it didn't work as stated in the book.
>
> If you can hoist a wire (or that twinlead) to the height you've
> described,
> the best way to utilize it is as a top-loaded vertical Tee. Simply
> tie both
> sides of that feedline together at the ground and feed it against
> radials.
> Tweak the length of the top horizontal section to bring the vertical
> to
> resonance. That will give you something on the order of 30-35 ohms
> at the
> feedpoint.
You may want to take advantage of your twin-lead other than just using
it as to parallel connected fed 2 wires.
Consider
it as a folded unipole vertical fed by gamma-match. -( source "
Vertical Antenna Handbook from Paul H. Lee, N6PL).
This has the advantage to increase the real-part of feedpoint
impedance ( R of R+jX ) .
Here is how it should go:
At the bottom:
Tie one end of twinlead-vertical to radials common point (ground).
Use the other as your feed point ( fed directly with 50 Ohm coax or
thru a capacitoras said elsewhere or L-network if not matched.
At the top ( at hight abt 20M times velocity factor of twin-lead
equalling a quarter wave-length of 80M ):
Tie both end of twin lead together on top . Tie to them your
horizontal section (abt 20 meters normal wire ) to complete your
antenna to in fact what it looks like :an inverted L as already said
in earlier posts. It should resonate at 160M. If you disconnect that
horizontal section, you should have a close 80M exclusive vertical.
( as opposed to 160M where you will have some horizontal radiation
lobes).
73
Pierre
F3WT
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