I had a similar problem when I installed the 2 element version
of this antenna. It turned out that the balun was faulty. Disecting
the balun revealed no problems, but when it was promptly
replaced by M2, the new unit made all problems go away and
worked for many years.
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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