Over the weekend I cobbled one of these together

http://www.greertech.com/hfloop/mymagloop.html

and was rather pleased with the results. My
version was made on a scrap wood hexangonal armature which allowed
approimately 15' 4" total loop circumference of salvaged RG58/u. It took
just over an hour to build, start to finish.
I tested it mounted on the roof of my camper van feeding a Sat800.
With my Barker and Williamson VR300 pi section tuner it has a frequency
range from about 2.3 Mhz up to somewhere around 26 Mhz...in short all of
the usual shortwave frequencies of interest. The tuning is fairly sharp
in all frerquency ranges, but not so much so as to be touchy. The Sat800
seems to have ample sensitivity to make up for the difference of
strength compared to the high long wire I usually use.
The most dramatic effect is the quiet! The noise floor usually
runs about S4 on the meter with the high long wire, but was reduced to a
barely registering S1 with the sheilded loop. An S6 signal is
completely in the clear. There is usually a band of RF garbage in my
neighborhood extending from about 17 Mhz up to about 23 Mhz which
normally obliterates the 15 and 13 meter bands. With the shielded loop
this was very much reduced...there wasn't a lot of activity on these
bands at the hours I was listening. I never heard WWV at 20 Mhz but did
hear one broadcaster in 13M band and some CW on 15.
I'm taking the van on vacation to the Shenandoah region next week,
will try this antenna out in the field, nd give further impressions when
I get back.



AR de KC2LVQ