Hi Rich,
4 verticals (4sq.) much better than 2 verticals which is much better than 1
vertical.
The wire 4 squares that I made for 80 and 40 blew away any other 2 L and
single vertical antennas that I used previously.
The F/B and F/S got much better as I went from 1 to 2 to 4 verticals.
Comparing 1 vertical to a 4 sq. is like comparing a single rotating element
to a 4L monobander WITH the ability to instantly switch direction!
Even with wire, the 4 squares if properly cut and tuned work VERY well. My
4 square elements all "bend" when they go through the tops of trees - this
introduces a high angle signal component that is not desirable, but this is
better than the alternative. There is also some question of whether or not
the performance of verticals are affected by trees and forests. I don't
know that anyone has ever really addressed and exhaustively tested this
assumption.
You can certainly use a single tree, or tower to support all 4 elements with
either a "T": configuration or an elements "Folded into the support"
configuration. Those designs work well also..
The MOST IMPORTANT consideration is that you ensure that the feedpoints are
the correct distance apart from each other in the "box". I have used twine
for this purpose between elements and to make the diagonals between the
elements. This keeps the "integrity" of the 4 square configuration and
makes a big difference in performance.
You WILL see a significant low-swr bandwidth improvement by using aluminum
tubing vs wire.
NO COMPARISON! I am all but convinced that the aluminum elements provide
better F/B, F/S and forward gain, but I have never modeled that. I would
think that this performance would be even more enhanced if you decide to
use Rohn 25 for part or all of the elements, not to mention providing
additional structural support against ravages of the ice, wind and forest
hazards so prevalent on the East Coast.
GL!
73
Bob KQ2M
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|