Mark, I fully agree.
The amount of unscreened signal picked up by an unscreened multi-turn loop
is negligible compared with what is picked up by the action of the loop
itself and then magnified by the Q of the loop. The unwanted signal cannot
possibly be more than that which would be picked up by a very short vertical
of height equal to the loop diameter and would probably be less.
If there's a problem it is more likely to be picked up on the feedline which
is not influenced by the presence or absence of a screen around the loop.
If something must be screened then screen the feedline.
Loop screening is needed only when precision direction-finding bearings are
being taken with an in-the-clear, precision-constructed, large loop.
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Reg, G4FGQ
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