https://archive.org/download/TNM_Manual_on_earth-resistance_testing_-_James_G__20180125_0208/TNM_Manual_on_earth-resistance_testing_-_James_G__20180125_0208.pdf
On 9/9/2021 2:51 PM, Artek Manuals wrote:
Jim et all
One of my heroes of the late 20th century was Ed Demming a noted statistician
( with a degree in EE of all things) who changed the way the world (most
notably the US and Japan in the 70's and 80's) looked at and tried to use
statistics to solve mass production quality problems through design of
experiments techniques. . One of Ed's famous sayings was "If you cant say it
with numbers..you don't understand the problem".
So I will say it AGAIN. What I want to do is measure the ground resistance of
a multi ground rod system in VERY POOR soils in my case. WHY I want to know
this number or what I intend to use it for IS NOT relevant to the discussion
at this point. Please don't get your cart before my horse.
No where in my original query did it indicate that this was for a vertical
antenna system ...but to clarify IT IS NOT. I followed N6LF's work on
measuring soil conductivity and did a lot of measurement to conclude that my
soil is very poor, in the range of .0015. But for the record laying out radial
fields in a jungle with a pure quartz floor is not really practical and I went
to elevated radials a long time ago.
I will happily spend the $10 if N0AX's book ...IF...it talks about actual
measurement techniques for deriving the resistance of a ground system composed
of several ground rods at any given frequency. Those of you who recommended
the book please verify for me that it talks about actual measurement
techniques WHY I want to know is not relevant to the question.
What I want to do is to be able to describe the problem with numbers using
verifiable measurement techniques at different frequencies.
Maybe I am writing an article for next year's April issue of QST for building
a 50 ohm dummy load using an array ground rods outside my shack window. Maybe
I am just curious.
Dave
NR1DX
On 9/9/2021 2:41 PM, Jim Brown wrote:
On 9/9/2021 9:41 AM, Artek Manuals wrote:
I 've read a lot of articles over the years about ground systems and how to
build a good one. Most of them ignore actual soil conditions and few talk
about the differences between "DC/AC (Low Freq)/Lightning" and RF ground vs
frequency
N0AX's ARRL book on the topic is excellent. Also, these two links may help.
The first addresses grounding and bonding, the second about
radial/countepoise systems for verticals.
http://k9yc.com/GroundingAndAudio.pdf
http://k9yc.com/160MPacificon.pdf
Some important points. The ONLY reasons for an earth connection are 1)
lightning safety, and 2) to make certain RX antennas work (Beverages and some
loops. An earth connection has NOTHING to do with noise reduction, and it
does NOT make TX antennas work better. That's the function of
radials/counterpoise.
73, Jim K9YC
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