Hi Rick, Thanks for your comments, and the correction on the split-stator cap. I'm sure that the refinements you suggest will improve the loop symmetry and null depth of the LW box loop, and when the full PVC loop article is finished, I'm hopeful of trying them out. They were a little beyond the initial scope of the project, however, which was simply to create a practical, large-size LW box loop on a PVC frame. Refinements can certainly be done at leisure. Last night I did take the opportunity to remove one of the coil turns from the LW box loop, which optimized the frequency coverage from 149 to 374 kHz. I'm very pleased with this range, so I'll go ahead and nail it down. The final LW box loop coil now has 21 coil turns of #18 wire, for a total length of 542 feet. The side dimension of the loop is approximately 6.5 feet. Of course, the ultimate value of this project will be in the comparison against other types of LW antennas, and hopefully some other DXers will feel motivated to build one of these giant LW box loops, and compare it with their existing LW antenna designs. 73 and Thanks, Gary DeBock In a message dated 5/5/2009 8:57:28 A.M. Pacific Daylight Time, [email protected] writes:
[email protected] wrote: > After adding three more turns of #18 wire to the 9' LW box loop, I now have > 567 feet of wire in 22 coil turns, and a tuning range from 142 to 350 kHz. > This should be OK for DX testing, so I'll probably wrap it up this way. > It's amazing how much wire you need to add to get the tuning range a little > lower, on LW. Yes, i sure is. And I think adding the spreaders, maybe 4 per side in each loop side for total of 16 would likely increase the upper tuning limit of the loop without decreasing the lower limit. These splay the turns apart, every other turn being spread in opposite directions. > The variable cap used in this project (and all the PVC loops) was a > compact, 8:1 vernier drive single-section unit from the eBay seller > "crystalradiosupply." This split-stator cap fits neatly inside of a section of 1.5" > diameter PVC pipe, for waterproofing the loop tuning system. If it's a single section cap it isn't a spit-stator cap, and can't be used with a loop primary winding center-tap. These center-tapped connections do improve loop symmetry and null depth. Rick Kunath _______________________________________________ IRCA mailing list [email protected] http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: [email protected] **************A Good Credit Score is 700 or Above. See yours in just 2 easy steps! (http://pr.atwola.com/promoclk/100126575x1221322931x1201367171/aol?redir=http://www.freecreditreport.com/pm/default.aspx?sc=668072&hmpgID=115&bcd =May5509AvgfooterNO115) _______________________________________________ IRCA mailing list [email protected] http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: [email protected]
