......
"The difference was startling, in favor of the flat-top dipole. I used the
same center height for the inv-vee as the flat-top height. As the
inverted-vee center gets higher than the dipole, the performance levels
out, and bringing the ends up helps also. Different heights and
frequencies will give vastly different results, but for the
typical 80 meter antenna up 40 or 50 feet, the difference is substantial.
...this fits with the rule of thumb U have always heard spoken that it is
the average height of the antenna that determines its performance...if you
are comparing a flat topped antenna with an inverted vee and the flat top
has a height of x and the apex of the v is also at height x, then the
flat-top will rule.....I believe the predominance of inverted vees is due
to ease of installation in the average amateur installation-especially
since most hams have one tower.
73,
Jim, K4OJ
Florida Contest Group - visit our website at:
http://www.4w.com/deemer/fcg.htm
The Florida Contest Group sponsors the Florida QSO Party, check out the FQP
website@:
http://home1.gte.net/wd4ahz/fcg/ssqp.htm
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