On Sun, 09 Jul 2017 14:29:18 -0700, Jeff Liebermann
wrote:

On Sun, 09 Jul 2017 14:16:20 -0400, Pat wrote:

On Sun, 09 Jul 2017 10:53:33 -0700, Jeff Liebermann
wrote:


How can a varying electric field from a noise source
not also create a corresponding magnetic field?

The transmitter generates both. You can reduce the sensitivity of a
receiving loop to the electric E field by shielding, leaving only the
magnetic H component.

I understand making antennas that are sensitive to only the H field.
My question is why would I want to? If the noise has both components,
how does an H field only antenna reduce unwanted noise?
Pat

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).

snip

I may soon see how well a magnetic loop really works. A friend
recently installed a 55ft tower and a collection of HF yagi antennas.
I bet him that I could build a magnetic loop antenna that would hear
the same stations as his monster yagi, but near ground level and much
smaller size and cost. The bet is for lunch at the local coffee shop.
This is going out on a limb, but I believe that it can be done
receive. Unfortunately, because of the narrow antenna bandwidth, I
can't use WSPR and PSK Reporter to compare gain and coverage.


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

Thanks for your responses.
Pat