On Jun 29, 2008, at 8:19 PM, Gregg Seidl wrote:
> I replaced my trusty A-3S with a Bencher Skyhawk.I wanted to take
> the A-3
> and mount it at 40 feet on my new Rohn 45 tower.It is mounted about
> 5 feet
> above the guys but it is NOT at the top of the tower.The tower is 85
> feet
> tall.I wanted to point it E/NE and jsut leave it there.
> We got it up for FD and noticed the SWR was not very good.It was
> great
> on the top of the old tower.We changed nothing.The guys are farther
> away
> then they were with tower top monting.The guys are steel but are 77
> feet
> long.The driven element is about 2 feet away from one of the legs of
> the
> tower.
> I'm lost as to why it changed,any ideas.The swr is about
> 2.5:1.Feedlines
> check good.Balun is good.
Gregg, I didn't see an answer to your question from this old message.
Here are some ideas:
It could be the guys are affecting the antenna. Rotate the antenna
about 90 degrees and see if the SWR changes appreciably. That might
indicate the guys are an interaction problem.
It may be that one of the trap connections has failed during the move.
The trap connections are terminated with sheet metal screws. These can
work loose or can corrode slightly and make the connection
intermittent or open.
If the antenna has been up for a while, it may be good to open up the
traps and clean them out. Often spiders or other bugs can get in the
traps and leave debris there. Make sure the traps are installed with
the drain holes pointed down, you don't want the traps to fill up with
water from condensation.
Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
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