Topband: 1/4, 1/2 or 5/8 vertical summery
Bob Eldridge
eldridge at direct.ca
Fri Jan 13 21:34:04 EST 2006
> The wire I use for my balloon held verticals is a Stainless Steel Wire
Rope.
> The material is 302/304, Diameter 3/32" and is 1 at 17 strands. Again with
six
> 1/4 wave radials number 12 copper wire on a clay and rocky soil. With this
> information can you figure the loss for a 1/2 and 1/4 wave vertical system
> on 160 meters?
"The loss" is a figure dancing on the head of a pin. For a given location at
a given time in a given direction under given ionospheric and geomagnetic
conditions a given antenna will be the best.
If a vertical is slightly off true vertical it will respond more to signals
from above, so if the balloon is not precisely overhead all bets are off.
It may be that one reason a 1/4 wave "works better" than a 1/2 wave is that
it DOES NOT discriminate so well against slightly higher arrival angle
signals (after 60 years of topband operation I am convinced that most
signals come in from higher angles than most people think - I also know that
if you live near the sea or on a big flat plain the band will open earlier
in the morning if your antenna responds to low angles. The band will also
close earlier with that antenna. It all depends what you want and when you
want it, and to cover everything you just have to have a CHOICE of
antennas.)
A very interesting thread, but there's not only no free lunch, there's no
satisfactory lunch that is good for everybody, at any price.
Bob VE7BS
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