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Re: [TowerTalk] Liberal Arts Question on Dipole Antennas

To: Lee Buller <k0wa@swbell.net>,TowerTalk Reflector <towertalk@contesting.com>
Subject: Re: [TowerTalk] Liberal Arts Question on Dipole Antennas
From: "Joe, aa4nn" <aa4nn@earthlink.net>
Reply-to: "Joe, aa4nn" <aa4nn@earthlink.net>
Date: Thu, 1 Jun 2006 16:45:55 -0600 (GMT-06:00)
List-post: <mailto:towertalk@contesting.com>
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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