With only one turn, maybe you could build a collapsible frame, with spokes which can be removed from a 'hub', or if you can find a beach umbrella with out any metal, to use as a collapsible frame.
I know it is not directional, but my 4 foot loop is usually hung flat next to the ceiling, where it is out of the way. - FARMERIK
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--- In ultralightdx@..., "jim_kr1s" <jkearman@...> wrote:
Yesterday I modified my 62-inch-tall PVC loop frame for one turn of
wire, which measured 7 uH. Calculations showed this loop should be 4 dB
better than the Hoop Loop. The frame is 1-1/2" PVC in a cross, and is
unwieldy indoors. It originally held a single-turn, tuned coax loop for
80 meters, which sat outdoors on a tripod until it broke the tripod.
Once I added the appropriate matching winding to the LW
transformer-resonator, on-air tests with local beacons confirmed the
calculations, showing a 4-dB improvement in signal strengths over the
Hoop Loop.
A few minutes of listening around sunset turned up two new beacons in
Florida. LW BC stations from Europe show a modest peak at sunset here,
and then get weaker until the sun starts rising in Europe, after 0300Z
(11 pm EDT). Conditions from Europe were fair then, with the usual
French, German, Algerian and Moroccan stations. BBC Radio 4 was weak,
which fit with the auroral image from NOAA.
On one last pass across the band, a few kHz above a beacon 30 miles
north of me, I thought I heard another one, but very faint. After a
minute or so, there it was: "MPG." No, not the latest import hybrid car,
but the airport beacon in Merida-Progreso, Mexico, about 730 miles away.
These three loggings were further confirmation that even slight
improvements in your antenna system can pay off. I had the matching
transformer arranged so I could unplug the PVC loop and plug in the Hoop
Loop. Then -- and this is important -- I had to tune the PL-380 off
frequency and back on, to tell it to tune the antenna. None of these
three stations was audible on the Hoop Loop, which is admittedly a tyro
on longwave.
Overall, not a bad return to LW after 5 days off: 3 new stations and one
new country. LW countries total now 11, and of course I'm scheming up an
even bigger antenna, for outdoor use on warm Florida nights. I hate to
say it, but the high-latitude Canadian observatories are showing
moderate disturbances in the last few hours, so I may have sneaked under
the wire with these loggings. Tonight I think I'll try the larger loop
on MW. It's hard to turn the thing without colliding with the furniture,
and the PVC loop has to go on the porch when company comes, so the Hoop
Loop need not fear a premature demise!
Date
UTC
KHz
Call
City
S/P/C
04-10
2321
206
VNC
Venice
FL
2345
221
FX
Ft Lauderdale
FL
04-11
0345
280
MPG
Merida-Progreso
MEX
73,
Jim, KR1S
http://kr1s.kearman.com/ <http://kr1s.kearman.com/>
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