I do something similar here. I load one of the verticals from my 80m array
on 160 with a base loading coil.
It's pretty simple... it's a coil about 5" in diameter made of 1/4" copper
tubing. The feedpoint impedance is rather low, so I use a hairpin matching
coil across the feedpoint to make it a perfect 1:1 match.
I've considered a full-size radiator, but it hasn't become a high priority
because the short vertical seems to work well enough. Running 1500w, I can
work anything I can hear and I listen on 600' Beverage antennas that border
1.8 million acres (~0.73 million ha) of national forest.
In other words, I think I hear pretty well and I can already work everything
I hear. Until I can hear like W4ZV I don't see much point in improving the
radiator.
It's worth mentioning that the vertical sits over a pretty large radial
field (about 40,000' of wire under the two 80m verticals). Some say the
radials become even more important for short radiators; perhaps part of my
results is because of that.
73,
Tom, NI1N
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|