Hi Lee,
You have some interaction between the 40m dipole
and the 80m dipole. Take down the 80m dipole
temporarily and ground its ends to your tower ground.
You can then find a lowest SWR on your 40m dipole
which should be 1.0:1
Gud luck
de Joe, aa4nn
-----Original Message-----
>From: Lee Buller <k0wa@swbell.net>
>Sent: Jun 1, 2006 8:26 AM
>To: TowerTalk Reflector <towertalk@contesting.com>
>Subject: [TowerTalk] Liberal Arts Question on Dipole Antennas
>
>Ladies and Gents....
>
> Recently, I had to replace my 40 meter dipole (more of an Inverted-Vee)
> antenna because the coax center lead had broken off the. The dipole worked
> OK, but I was never really sure that I liked it. What is there not to like
> about a dipole antenna? (I sure I get some wise cracks here). The dipole
> did not seem to have a resonate point. It was below 1.8:1 on CW and was
> about 3:1 on SSB. So, the antenna was long.
>
> The new antenna, using a Budwig connector this time, shows the same
> characteristics. I cut the the antenna at 66 feet and I made sure that both
> sides of the antenna were the same length....33 feet. The antenna is mounted
> at 45 feet using a bracked that runs through the tower. The antenna in
> question is on the east side of the tower while an 80 meter antenna is on the
> west sime of the tower mounted on the same bracket. The feed points are
> about three feet apart....on seperate coax feeds.
>
> The end of the Inverted-Vee on 40 comes down to about 20 feet off the
> ground...while the 80 meter antenna ends about about 12 feet off the ground.
> The 80 meter antenna is in a straight line, while the 40 meter antenna has a
> slight VEE to to the tie points. So it has VEE to the the east....and a Vee
> down. This is hard to explain in words. I hope you experts get this.
>
> The new antenna was failry good on SSB but not great ... about 1.8. I
> attached two test leads to each end and the antenna show that it was at 1.8
> on CW...around 7.025. It seems that the test leeds were too long and now it
> is resonate below 7.0.
>
> But, there seems to be a crazy problem that I cannot get the anntenna any
> lower than 1.8 to one....thinking that there should be a length in there that
> should be "perfect." I cannot find the "perfect point" which I would like to
> have around 7050.
>
> Reading the Antenna Handbook...this antenna is working as stated although I
> did not anticpate the length of an inverted Vee to go longer. I've read the
> articles, but it seems there is something wrong with the antenna.
>
> Is there an interaction between the tower...the 80 meter antenna...the Vee
> to the east?
>
> Is the coax bad? IT has been up there for quite some time and it was used
> at another location before I put it up here.
>
> Comments, flames, postulations, editorials, and pontifications are all
> welcome. They might show on my web pate later on....so...you have been
> warned.
>
> Thanks for the discourse on a simple dipole
>
> Lee Buller - K0WA
>
>
>In our day and age it seems that Common Sense is in short supply. If you
>don't have any Common Sense - get some and use it. If you can't find any
>common sense, ask for help from somebody who has some common sense.
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