Thread: Magnetic Loops
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Old October 15th 15, 03:36 AM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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Default Magnetic Loops

On Wed, 14 Oct 2015 20:38:23 -0400, rickman wrote:

I hope you realize that your experiment is not at all conclusive since
wrapping the duct tape around your loop changes many things other than
just adding a shield. Those other effects may or may not improve any
given loop antenna.


Yep. However, wrapping did improve the SNR a few dB, which is a sure
sign that I must have done something right.

Do you understand the details of how such a shield should work? The
link you provided gives several conflicting opinions on this including
one very detailed post which claims there is little or no suppression of
the E-field, rather it is only the nulls that are useful.


It gets worse, I just found this link, which says my explanation
doesn't work:
http://www.w8ji.com/magnetic_receiving_loops.htm
What little is mentioned about shielded loops claims that it does not
suppress the E-field and details how skin effect makes it work. I
gotta work through this again to make sure I understand it.

It was finding posts like this that have made me doubt the suppression
of the E-field by the shield.


Yep. The author of the above article definitely agrees with that. It
may take me a while before I agree, but only after I understand how a
shielded loop really works.



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Jeff Liebermann
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