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Re: Topband: Ant Analyzer Assistance request -- funky readings

Subject: Re: Topband: Ant Analyzer Assistance request -- funky readings
From: K4SAV <>
Date: Thu, 24 Jan 2008 16:23:45 -0600
List-post: <>
Rick Hiller wrote:

>I was helping a friend put his ‘postage stamp lot --low to the ground’  80
>meter loop on 160.  So, we opened the loop to cause a ½ wl 160 antenna
>folded into a polygon.
>Placing the MFJ-269 analyzer at the loop (open or closed) feed point shows
>fairly appropriate readings at 3.600 (R 98 +J25) , but anything outside this
>range down thru 1.8Megs and below, or up toward 7Megs shows continuous R
>values of ZERO with a varying j value.  Measurements were taken right at the
>feedpoint, which is 45 degrees off center (approx).
>My concern is the ZERO R value -- for even occurring, but also that it
>occurs over such a very wide range of frequencies ..............

The same reading on 3.6 MHz with the loop open or closed really threw me 
for a moment until I realized that this is an off-center-fed open loop. 
So about 30 feet high should get you into the low teens for R on 160, 
including resistance loss. That should be readable on the MFJ although 
it's not much meter movement. The MFJ could be a little out of 
calibration on the very low end, or more likely it is getting just 
enough broadcast station RF to mess up the reading.

Jerry, K4SAV
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