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Old July 11th 17, 12:35 PM posted to rec.radio.amateur.antenna
Pat[_7_] Pat[_7_] is offline
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First recorded activity by RadioBanter: Oct 2013
Posts: 22
Default Magnetic receiving loop theory

On Mon, 10 Jul 2017 18:36:07 -0700, Jeff Liebermann
wrote:

On Mon, 10 Jul 2017 06:28:08 -0400, Pat wrote:

On Sun, 09 Jul 2017 14:29:18 -0700, Jeff Liebermann
wrote:
That should be the E and B field, not H field. My mistake.


E and H are fine. I think it depends on which books you are reading
or maybe how old you are? I remember E and H from school (a long time
ago).


At this time, I'm 25,384 days old[1]. That's long enough to have
forgotten or confused most everything which I had pretended to learn
in skool.

I am 1.088 kilodays younger than you. Not much in the overall scheme
of things. (Thats only 78 fortnights. I had a professor in school
who would measure velocity in furlongs per fortnight.)

I'm perpetually mangling the various fields. So, I decided
to search for some clarification. This is least confusing explanation
I could find:
https://www.physicsforums.com/threads/in-magnetism-what-is-the-difference-between-the-b-and-h-fields.370525/#post-2537765
I think I understand most of it, maybe, or at least some of it:
https://www.physicsforums.com/threads/in-magnetism-what-is-the-difference-between-the-b-and-h-fields.370525/
There are 114 articles in the thread, most of which disagree with each
other. That suggests that not everyone understands the various fields
in quite the same manner.

E and B are the total electric and magnetic fields.
D and H are the free electric and magnetic fields.
P and M are the bound electric and magnetic fields.?
E = D + P (except that for historical reasons E is defined
differently, so we need to multiply it by the permittivity,
and for some reason P is multiplied by minus-one).
B = H + M (except that for the same historical reasons
B is defined like E, so we need to divide it by the
permeability).

At this point, I usually say "I hope this help". However, I think
that "I hope this doesn't hurt too much" might be more appropriate.

True, but I appeciate your responses anyway.


I look forward to hearing the results. Sounds like a great
experiment.


I'll post something. Right now, I don't see it happening until after
I design and build the one, true, ultimate, and best magnetic loop
antenna. Probably next year.


Sounds good. As an aside, I just watched a youtube video of someone
trying out one of these magnetic loop antennas. With his particular
set of circumstances, it reduced the noise floor on 80 meters
significantly.



[1]
http://www.calculator.net/age-calculator.html?today=01%2F10%2F1948&ageat=07%2F10 %2F2017&x=54&y=14