Length & number of radials
On Fri, 21 Jul 2006 11:28:02 -0500, "hasan schiers" wrote:
"Reg Edwards" wrote in message
...
In the case of RADIAL_3 the obvious purpose of the program is to
assist with choosing an economic length and number of radials to be
used with a given test antenna height. It is also educational in that
after reading the introductory notes and using it, the user will have
a better understanding of how radials work.
snip
================================================= ======
We need to know: does the predicted attenuation of current along a radial
wire happen as quickly as you predict? This can be measured. This can be
modeled. That's what makes this fun. Let's find out. Let's see what agrees
with what and what doesn't. Then we can conjecture as to why, and which
approach is to be "believed".
================================================= =======
snip
...hasan, N0AN
I've been reading this thread, and sent the following msg to hasan. I then
decided to post it here for others to see.
Walt, W2DU
Hi Hasan,
I've been reading the radials thread on the rraa, with the works of BLE bandied
about. I have a copy of BLE in PDF that I can put on a CD and mail it to you if
you don't have a copy, which I'd be pleased to do.
Incidentally, I worked for many years with Jess Epstein, the 'E' of BLE, in
Brown's antenna laboratory at the RCA Labs in Princeton, where Brown is the 'B'
in BLE. I also know Bob Lewis, the 'L' in BLE, as we've spent many hours
together as hams. Bob is W2EBS.
Bob and I were attending a ham meeting in NJ in the 1960s where Jerry Sevick was
demonstating how radials worked with verticals. He had annular rings of wire
connecting all the radials at various radial distances from the center. He even
had a wire connecting the ends of all the radials together. I asked him what the
annular rings were for, and he replied that they kept the currents in each
radial equal. I asked him if he was acquainted with the BLE paper, and he said
he had heard of it but was not familiar with it. So I asked him if he'd like one
of it's co-authors to explain it He agreed, but was totally shocked to know
that Bob Lewis was in his audience. Bob then proceded to straighten Sevick out
on how radials worked. A fun night, indeed.
The graphs reporting BLE's measurements are pretty conclusive. In addition, the
BLE paper is the basis on which the FCC set the requirements for the ground
systems on all AM BC stations since 1939. So there's thousands of empirical
proofs of the correctness of their measurements in every situation where field
strengh measurements were required for proof of performance.As I'm sure you
already know, for every AM BC station that uses a directional antenna system the
FCC requires field strength measurements. There has never been any such
measurements that disagreed with those of BLE. Even Tom's (W8JI)
Please let me know if you'd like me to burn you a copy of BLE.
Walt,W2DU
PS--If any others reading this would like a copy of BLE let me know and I'll
burn it for you.
|