> Secondly, I don't often disagree with Tom, but I did not
experience a
> problem with my 160 shunt fed vertical when I hung an 80
meter sloping dipole.
>
> There was no change in the tuning and I did not "see" a
difference in
> performance.
I mentioned Inverted Vee dipole or a sloper in reference to
suggestions an Inverted Vee dipole or 1/4 wave sloper be
hung from the tower.
The problem is the tower is a hat loaded vertical. When you
have feedlines attached or very near the vertical element
and that feedline is also connect to something spread out
from the vertical element, a good deal of current tries to
flow out onto that wire (especially if it is 60 feet long).
If you have a balun at the feedpoint of an Inverted Vee the
stress on the balun is very large. With a sloper the shield
of the feeder is attached to the tower, and the tower is hot
with RF. Generally bad news.
If all the tower does is support the end of a wire and the
feeder for that antenna is kept away from the tower by a
long distance, no problem!! Often works fine. Same for a
marconi 1/4 vertical hanging a few feet from the tower and
worked against a good ground system instead of the tower.
Likely to work.
73 Tom
_______________________________________________
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
|