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Old January 23rd 06, 08:47 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Default Vertical on a tower

wrote:
The dipole was at 36 ft. The base of the GP was at 36 ft.


Well, there's the problem. You stopped your dipole where
your vertical started so any comparisons are bogus. Your
dipole was an NVIS antenna. :-) It's not a fair comparison
since the vertical was given a 2x height advantage. (That's
like putting my three foot six inch grandson up against
Shaquelle O'Neal in basketball. :-) Put the dipole at 70
feet, like the vertical was, and see what happens.

The top of my vertical was at 53 ft. and my dipole was
one of its upper guy wires at about 50 feet so the two
heights were essentially opposite yours.

Which brings up another question. If the top of a vertical
is at a certain height, what height of dipole would be a fair
comparison? It is certainly unfair to compare feedpoints
at the same height, like you did. It may also be slightly
unfair to compare them at the same maximum heights, like I did.
It seems a fair comparison might be made when half the vertical
is lower than the dipole and half is higher than the dipole,
i.e. the height of the dipole is at the midpoint of the
monopole?
--
73, Cecil
http://www.qsl.net/w5dxp