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[TowerTalk] Re: tuning M2's 40m1L antenna

To: <towertalk@contesting.com>
Subject: [TowerTalk] Re: tuning M2's 40m1L antenna
From: jonk@jskent.com (Jonathan Kaplan)
Date: Sun, 4 Jul 1999 14:31:09 -0700
Ok, Guys, we're getting somewhere. I first tried the normal setup (into the
1:1 balun) with a uncoiled length of RG58 (the only cable of any length I
could liberate)between the MFJ-259 and the balun. It showed SWR 3+ (5 or
10?):1, the same as the 9913 jumper I had been using.

Next, I coiled the RG58 as instructed and connected that to feedpoints on
the antenna--bypassing the balun. When the balun remained connected to the
feedpoints, the SWR improved only marginally--3.5:1. But when I disconnected
the balun from the feedpoints the SWR changed decisively -- 2.75:1. Still
not great, but maybe that tells us more about what's going on.  BTW, what IS
going on?

Thanks Again

Jonathan KO6XS


-----Original Message-----
From: Phil Clements <philk5pc@tyler.net>
To: Jonathan Kaplan <jonk@jskent.com>; w5ozi <w5ozi@ktc.com>;
towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Sunday, July 04, 1999 12:50 PM
Subject: Re: [TowerTalk] Re: tuning M2's 40m1L antenna

>
>Try this test....remove the balun and connect the coax directly
>to the antenna. At the feedpoint, roll up the coax into a 8-10
>turn coil about 10 inches in diameter which makes a choke balun.
>I agree that there is no way to tune that antenna near ground level,
>but whatever your readings before the change should remain the
>same if the problem is in the antenna itself.  This at least is a
>cost efficient way of eliminating  the existance of a balun problem.
>
>GL!
>
>(((73)))
>Phil, K5PC
>
>-----Original Message-----
>From: Jonathan Kaplan <jonk@jskent.com>
>To: w5ozi <w5ozi@ktc.com>; towertalk@contesting.com
><towertalk@contesting.com>
To: <towertalk@contesting.com>
>Date: Sunday, July 04, 1999 2:10 PM
>Subject: [TowerTalk] Re: tuning M2's 40m1L antenna
>
>
>>
>>Pat,
>>    I agree that the freq. of the best SWR will change as the antenna is
>>raised. But that shouldn't prevent me from getting a good SWR SOMEWHERE on
>>the spectrum. Right now, the best I'm getting is 3+:1.  Not good! The only
>>change I see downward is when I touch one of the linear loading rods. And
>>that's why I need know  what affect my touching the antenna is having.
>>Maybe, you have a better insight into what might be wrong here.
>>
>>Jonathan
>>
>>-----Original Message-----
>>From: w5ozi <w5ozi@ktc.com>
>>To: Jonathan Kaplan <jonk@jskent.com>
To: <towertalk@contesting.com>
>>Date: Sunday, July 04, 1999 11:36 AM
>>Subject: Re: tuning M2's 40m1L antenna
>>
>>
>>>As long as you are holding the antenna right at the mounting plate, it
>>>shouldn't matter whether it is grounded or not, but if you have to touch
>>the
>>>antenna on either side of the mounting plate it will obviously change
>>>things.  Doesn't the instruction manual suggest exact dimensions  for
>>>matching?  I cannot imagine that you could set the match at 7 feet AGL
and
>>>have it even close when it is up on the tower.  Pat
>>
>>
>>
>>--
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>>
>>
>
>
>--
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>


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