[Lowfer] Copper pipe loop question

[Doug Reed]

Hi John.
Check YouTube for the W1VLF channel. He did a series of loop antenna videos
a couple years ago. The largest was made of screen about 2ft wide and 6ft
square.  And it was broadband coupled with a toroid as you are suggesting.
But his results were that it was good for MW-LF-VLF, but lousy for HF.
Before that he made a large pipe loop antenna (4ft sq?) but I don't
remember the specs. That one ended up hanging from a tree to allow
rotation. As I remember he had fairly good luck with the ferrite coupling
and a 2 or 3 turn secondary feeding coax to the receiver. But you had to
choose the ferrite for your primary range of interest. The type 31 ferrite
favors low HF and down, while type 43 is a bit more full range HF? I found
it interesting how he could turn and tilt the loop to maximize rejection of
a strong signal.
73, Doug Reed, N0NAS.