Longwave slowly returning


jim_kr1s <jkearman@...>
 

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/ 

Join main@UltralightDX.groups.io to automatically receive all group messages.