On Sat, 29 Aug 1998 18:09:59 EDT W6osp@aol.com writes:
>What Is this Pennant I have been reading about? Bruce
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It's a variation of the Ewe that Jose, EA3VY and I developed using
antenna modeling software.
The Ewe is very much influenced by the soil conductivity over which it is
erected, requiring widely different-sized Ewes and widely different
termination resistor values for best results depending on the soil
conductivity. Also, the Ewe requires two good ground systems, one at
each end of the antenna.
The Pennant was developed to preclude these shortcomings of the Ewe. The
Pennant is virtually "terra-proof", as Jose says. It is totally above
ground and requires no connection to ground. Different soil
conductivities have virtually no effect on its directivity and input Z.
It is also very broadbanded, with 30 to 40 dB F/B from 1.8 to 7.5 mHz.
I have named it the "Pennant" because of its triangular shape which
resembles a pennant when erected. It's optimum size it 14' high and 29'
long, with the top at 20' high and the bottom at 6' high. The
termination resistor (900 ohms) may be installed at either the "point" of
the Pennant, or in the center of the vertical section. The feedpoint
also may be in the center of the vertical section or at the "point", at
the opposite end of the antenna from the termination. The input Z is 900
+ j0 ohms on 160m.
Its height may be raised to 40' at the top or reduced to 3' high at the
bottom with very little effect on its performance.
Directivity is the same as an Ewe, with a cardioid pattern with a deep
null to the rear (about 43 dB F/B on 160m). Gain on 160m is about -36
dBi, increasing to about -12 dBi on 40m. No preamp is needed for it
with my FT-1000MP.
We've also developed the "Flag" antenna, which is rectangular with the
same dimensions (14' vertical, 29' horizontal, with the bottom wire 6'
above ground). It performs identically to the Pennant, but with about
-30 dBi gain on 160m. It is terminated (by 950 ohms) and fed in the
centers of opposite vertical sections. Its input Z on 160m is 950 + j0
ohms.
Another similar configuration we've come up with is the Diamond.
Some hams are planning rotatable use of the Flag or Diamond using quad
element construction methods.
73, de Earl, K6SE
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