Hello Gary and all, The answer to your question depends on how quiet your
location is. If you have an extremely quiet location I would go with another
section of tubing for 23 feet overall with the Hi-Z. If your location is
pretty normal for noise then 18 feet or so will be fine with the Hi-Z
array. There are times here in the early morning when the band noise drops
below my array noise for a short period of time and I have been using 20
foot elements.
Another point to consider is 3/4 inch fiberglass rod is easy to get and
has proven strong enough for element insulators. Adding a few feet of 3/4
tubing to each element would make your insulators much easier to construct
and increase array gain. You can always add more length later as you see the
need.
Four inches of overlap has seemed to work well.
Lee K7TJR
>I've decided to make the plunge and buy one of the 8 element active arrays
for 160M-40M. Looking at the price for the antenna kit, it's just too much
considering the cost of the electronics, so I need to roll my own.
I was thinking of getting the Telescoping Aluminum Tubing that comes in 6'
lengths from Texas Towers; .375", 5" & 6.25". If I slide each inside 6",
that'll come to a 17' tall element. Is that sufficient height? Would adding
another 2-3 feet make any difference with these kind of active antennas?
73,
Gary
KA1J
_________________
Topband Reflector Archives - http://www.contesting.com/_topband
|