NEC-LIST:NEC2 and Beverage antennas

Hi All:

When I compare the results of my NEC2 models of Beverages with my previous
calculations, I am seeing some significant differences. Also, my NEC2
Beverage models aren't matching published data in papers such as Litva and
Rook's report and also Knight. I assume they don't match Beverage himself.

For example: in Litva & Rook, the theoretical beamwidth of a certain
Beverage is about 35 degrees while my NEC2 model gives 57 degrees. The front
to back ratio should be about 25 dB with the given parameters while I get
only 13 dB.

Things get even worse. My velocity (propagation coefficient) should be near
90% but mostly the values are near 30%.

I can guess that I have made at least one large error and that would be the
load placement and grounding. I'm not terribly sure what I need to do about
connecting the load to ground (via radials? How many?) and how to insert a
termination. Is there a way to have NEC2 calculate the ZO and
automatically terminate the antenna with the correct complex termination?
I'm not having correct results when inserting the load at the top end of the
connection from the Beverage wire to earth, and am wondering whether I have
the afore-mentioned ground model problem or my idea of the load placement
(modelling) isn't what I think it should be.

Any pump priming would be very gratefully received. EZ files would of course
help if I were to be so lucky as to find some.

Thanks,

Chuck

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