Add more short (50 - 60 foot) radials, IMHO. Some 45 years ago I worked as
a wireless operator in fixed service on 60m band (my call has been 4NC24L)
and we used L antennas. At my surprise, ground was just 3' of galvanized
pipe knocked into the ground. At company's electrician workshop I got heap
of scrap insulated copper wire different lengths which I used to lay down
some 40 or 50 radials different lengths, (in a half circle due to building
in which we were located). My signal improved so much net control asked me
what I was done and was asked to travel to another stations to install
radial systems there as well...
73, Mirko, S57AD
V V pon., 2. sep. 2019 ob 21:08 je oseba N4ZR <n4zr@comcast.net> napisala:
> More as an experiment and a thought-provoker than anything else, I've
> started adding 50-60-foot, on-the-ground radials to my 135-foot inverted
> L. In the latest incarnation I'm up to 4 radials. On my ancient
> MFJ-259B the lowest SWR is 1.3:1 at 1825 KHz, with an R of 77. X=0 (the
> 259B doesn't give the sign of j) from 1808 to1894, which I assume is
> roughly centered on the actual cross-over point.
>
> With my rudimentary knowledge of such things, I'm guessing that there
> remains something on the order of 50 ohms of ground resistance to be
> reduced for efficiency, through addition of radials. Question is,
> would I profit most by adding another 4 50-60 foot radials, or 2 radials
> each 100-120 feet?
>
> Comments appreciated.
>
>
> --
>
> 73, Pete N4ZR
> Check out the Reverse Beacon Network
> at <http://reversebeacon.net>, now
> spotting RTTY activity worldwide.
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> "retail" DX cluster.
>
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--
Mirko S57AD
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