Hi Steve and all,
> In a message dated 98-08-19 16:10:03 EDT, w9rpm@lse.fullfeed.com writes:
>
> << My question is will this be possible
> without interaction and will it perform better than the inverted V for
> 80m? >>
>
> Yes. A high horizontal dipole is a wonderful antenna. An inverted
vee has
> some cancellation problems that reduce it's efficiency a bunch
(scientific
> term).
Folding the legs down mainly changes efficiency by decreasing feedpoint
impedance and lowering the effective height of the antenna. If we "vee" the
antenna enough to increase current by twice the amount, the LOSS in the
antenna conductors will be 4 times greater (that would mean feedpoint
resistance at resonance would drop to about 1/4 the value of a dipole at
the same effective height). That would be one VERY tight V, and yet
conductor loss would jump from one percent to maybe four percent of total
power!!
The majority of loss is external to a copper wire dipole antenna using any
reasonable size wire (such as ground loss in the area below the antenna
and feedline loss). Antenna efficiency is generally near 100%, even if we
"V" the antenna.
There is precious little difference in directivity or efficiency. The
biggest problem is the effective height is reduced by drooping the legs.
Model it, and you will see the VERY small difference between an inverted V
DIPOLE and a regular dipole.
73 Tom
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