Rick Hiller wrote:
>Hello,
>
>
>
>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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