I want to take this opportunity to thank several members of the list for
responding to my question about elements being out of exact horizontal. A
number of people had personal experiences that they could report, and
several great towertalkians went to the effort to model the effects on
their software programs, which was really what I was hoping some
industrious towertalkian would do....
thank you very much.
What is clear from the models and the personal observations is that having
the reflector out of exact horizontal will have a small deleterious effect
on gain, but a much more significant effect on front to side. That is
great. I really appreciate it.
One fellow encouraged me to get up the tower and make the change. In my
case, the 40 is 10 feet above the 205CA on a mast with no foot-holds and
even I had enough to drink apriori to get me to actually try that shinny up
the pole (110' up to begin with), the rough part would be crawling out on
the stock Mosley aluminum boom 10 feet from the center support (with no
boom truss supports), loosening the element clamp, and getting the element
horizontal. Given that I currently weigh 215#, I think that this might be
just a little bit dangerous !!??!! (Grin)
This job is going to have to wait until I either
1.) am able to snag the element with a ground line and pull it horizontal
(with a little pushing up from a guy on the tower),
2.) removal of the rotator, dropping the whole darn 20' mast down inside
the tower, removal of the yagi, and pulling the yagi over to the tower for
adjustment, or
3.) the next time a 150' crane passes down my road and I have the presence
of mind to offer the operator a case of beer to detour into my "back 40" to
pick the yagi off the top and let me make the adjustment.
Seriously, I hired a professional tower climber (like the kind of fellow
that will climb up a ladder on the side of a 2,000' tower to make
repairs....) last summer to handle some damage from a lightening strike
that I was physically not able to deal with, and I have found that almost
all the work that he did, has had to be done again at least once (by me
this time), since everything he did seemed not to have been tight enough or
torqued enough to handle typical "ham" installations.
Gary W5FI
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