I have recently uploaded a pdf file, "BPloops2.pdf", with an article
describing loop receiving antennas I have built recently for the 500kHz and
136kHz bands, to the UK500kHz google group site (
http://groups.google.co.uk/group/uk500khz , then select "files" from the
menu).
These designs are an update of the "Bandpass loops" article I wrote some
years ago (still available from G3YXM's "features" page). They are 1 metre
square single turn loops with an element made of copper water pipe. They
have a bandpass characteristic, to give coverage of the amateur band plus a
bit more without re-tuning, while at the same time giving useful rejection
of out-of-band signals. With the preamp also described in the article, they
are sensitive enough to hear the band noise under quiet band conditions.
There is also a switched dual-band version.
If you can't access the UK500kHz group for some reason, let me know and I
will send the file direct.
Hope this is of interest - Any comments welcome,
Cheers, Jim Moritz
73 de M0BMU
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