Hi Pete,
Unless you're planning more than 30 radials eventually, there's no reason
to install radials longer than the 50-60 feet you're already using.
This is one of several classic references on the topic. See
see Figure 3 and the 160 meter column in Table X:
https://ncjweb.com/bonus-content/k3lcmaxgainradials.pdf
73
Frank
W3LPL
----- Original Message -----
From: "N4ZR" <n4zr@comcast.net>
To: "topband reflector" <Topband@contesting.com>
Sent: Monday, September 2, 2019 7:08:16 PM
Subject: Topband: Inverted L redux
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
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