Bill: My comments are below. Dick Weber K5IU's papers on the subject includes equations for calculating force of the wind on tubular elements and booms, all of which start with the calculation I desc
Mike, Bill, et al: Hold everything! Multiplying by 0.6 or 0.67 as a shape factor is NOT the correct number. It's 1.2 - at least according to Mechanical Engineering in Radar and Communications, one of
I take it that no one finds my suggestion of collecting physical measurements of antenna components of value. Oh, well,... back to the hole in my yard! 73 de Gene Smar AD3F --Original Message-- From:
TT: I gave up on digging the hole by hand! (I can hear the I told you so's now.) Paid a fellow around here to come by this afternoon. He made quick work of getting down to the proper depth, but he co
TT: Not much accomplished since the last update except I framed out the cap (above-ground piece of the foundation) and set the rebar cage. I temporarily left the top two pieces of horizontal rebar an
TT: Bottom section bolted together and set on top of cap (and missing pieces of rebar cage installed), hole was inspected this morning (and passed), Georgia buggie and vibrator will be delivered on W
TT: That tower ain't goin' NOWHERE! This afternoon Bill N3RR and Pat, my neighbor's son, came over to help with the concrete. After we waited for over two hours, the truck finally arrived. The best w
Speaking of off-topic topics: Anybody have a used CC D40 rotatable dipole and/or a CC 13B2 Boomer w/balun and/or a M2 2M9(12) they'd like to sell? Prefer within 50 miles of DC area, but we can discus
Mike: I'm planning for a self-supporting tower in the back yard at my QTH. I debated the same things: slotted or solid conduit; DB jacket or not; corrugated or smooth; gold or silver (just kidding.)
Eric: This entire project sounds too "iffy" - lots of back-of-the-envelope calculations, opinion, conjecture, don't want to/can't spend money for a proven solution (crane), etc. All obtained over the
TT: Mark hasn't written a book (yet) but his work, found at http://www.qsl.net/n1lo , is well worth a look. (And I've told him so.) 73 de Gene Smar AD3F --Original Message-- From: Tom Osborne <w7why@
Gerry: The Bencher Skyhawk had a similar problem until they came up with a set of phenolic spacers. But I'm afraid they might have patented it. ;>) 73 de Gene Smar AD3F --Original Message-- From: Ger
All: The variation in SWR during QRO operation with certain autotune amps is the main issue with open sleeve-fed Yagis. In an earlier posting I mentioned (tongue in cheek) that Bencher developed a so
I've had one of these 30 foot masts in use in one form or another for over 20 years. They're worth the listed asking price. (Suggest you use a through-bolt between sections, though.) 73 de Gene Smar
TT: I just finished putting together an equation to calculate the angle of max wind force on a Yagi. (I couldn't find it in my own TT archives, and wanted to shake the cobwebs out of my forty-somethi
Guy: Thanks for the comments. I agree that flexible elements (Skyhawk) are likely to shed wind by bending a little,thereby reducing the actual force on the element/mast/tower. Would it be safe to say
Hi, Kurt: If what you're asserting here is accurate (which I haven't satisfied myself that it is yet), then what you're saying is that my calculations show exactly the OPPOSITE of what I think they s
TT: I'm feeling less and less certain that my equations are correct! Thanks to Kurt, Steve, Michael and Guy for pointing me toward previous sources. I've inquired from the sources about reprints of t
TT: I bought a half-dozen ground clamps from Harger for my soon-to-be-delivered Trylon Tower. The clamps are their model 213T, tinned bronze with stainless steel bolt and washer. If anyone is interes
Josh: Whatever you do with antennas, assume one thing - That electric supply wire is lethal! Don't fling an antenna or guy wire across it, even temporarily! Make sure your tower, if you go that way,