Ollie and the gang,
And the winner is....
The vertical antennas were modeled with 15 ohms of extra ground loss to
account for NEC-2 not fully modeling ground losses. One 90-deg radial is run
along
the ground directly under the horizontal wire. The dipole is an inverted-vee
at 65 feet, and 140 feet long. It is loaded with two 35 uH, Q = 300 coils.
15 deg TOA:
DIPOLE -8 dBi
90-deg Inv-L -5 dBi
135-deg Inv-L -8 dBi
30 deg TOA:
DIPOLE -3 dBi
90-deg Inv-L -5 dBi
135-deg Inv-L -2 dBi
50 deg TOA:
DIPOLE -0 dBi
90-deg Inv-L -3 dBi
135-deg Inv-L -2 dBi
70 deg TOA:
DIPOLE -2 dBi
90-deg Inv-L -11 dBi
135-deg Inv-L -2 dBi
For your use it looks like a toss-up between the 135-deg Inv-L and the short
dipole. For you use. For all around goodness I think the 135-deg Inv-L is the
winner.
If you decide on an antenna I can send you accurate data on loading,
matching, VSWR, etc. I'll also look into the inverted-U today. I have not done
much
modeling with these. If you look at the inverted-L's they are sideways U's.
Like
a vertical dipole with the ends bent to the horizontal. Due to being close
the ground the bottom dipole wire suffers high ground loss.
BTW, I'm finally springing for NEC-4 so that I can more accurately model
radials in the ground. With NEC-2 I have to add some base loss and hope for the
best.
Dave WX7G
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