Thread: Magnetic Loops
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Old October 14th 15, 08:32 PM posted to rec.radio.amateur.antenna
Roger Hayter Roger Hayter is offline
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Default Magnetic Loops

rickman wrote:

I just read the wikipedia article on small loop antennas and it seems I
was laboring under a misapprehension. I thought receiving loops were
"magnetic" because they were shielded (this is often stated in various
web pages about constructing such loops). But the wikipedia article on
small loop antennas says the nature of a small loop is to not be very
sensitive to the E field in near field.

So if the shield has little to do with rejecting near field electrical
noise, what does the shield do? A lot of antenna designs make a big
deal of the shield. So I assume it must be a useful addition to the
small loop antenna for some purpose.


I have read that the electric field sensitivity is non-directional, and
therefore interferes with directivity even though the sensitivity is
low. I have no idea if this makes sense when worked out quantitatively.

--
Roger Hayter