The other day I received an email requesting info on my Moxon 40m mod for the Cushcraft XM240, as used at K3LR, 8P5A, K1KP, WE9V and others. A specific question was, "What is the exact element spacin
The story on modeling the Moxon Yagi is that I got lucky. Because I had been working with Brian, K6STI, I designed this antenna in 2003 using AO, and built it to the dimensions it produced. No offset
Thanks all. 256.75" it is. One more question: The Cushcraft 1-3/8" center element sections EA and EH have internal reinforcement, as is clear by the fact that the fiberglass center spacer is 1" OD bu
... and any reinforcements in the EB and EC sections? TU On 1/9/22 2:26 PM, Leeson wrote: Thanks all. 256.75" it is. One more question: The Cushcraft 1-3/8" center element sections EA and EH have int
I've been using a TIC ring rotator here on a big 7el 10m Yagi for the past 20 years with good success, but it has a couple of well-known unresolved problems: In the high winds we have on our hilltop
I do two things here on windy ridge: when the power's off I use relays to put a short circuit across the DC motor in the prop pitches and also the TIC Ring (2-motor). A DC motor with shorted terminal
I guess emails with attachments just don't make it, so here's a repeat: Here's the story on the flexdisc ("Giubo") isolator: I learned about flexdiscs because my race car used them on the rear (drive
Sorry, it's 26-11-1-229-065, I'd recommend the OEM Febi-Bilstein unit. _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mail
Here are the attachments re flexdisc mounting. Thanks to K7LXC. Dave _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailma
My thought on this is that the very shallow angle grazing reflection from the dielectric discontinuity at the distant ground surface is pretty much 100%. The ground permittivity and conductivity vari
This looks like a very good call. I was browsing various other catalogs for Delrin 64 pitch hub spur gears, and eventually came up with the same page Jim had already identified. I should first have r
If you're really curious about the Zo of a transmission line, you can measure it with almost any antenna impedance instrument: At one end, put a resistive load you expect will be a mismatch, say ZL =
Ah the memories! I saw my first ham radio setup when I was 4 years old, and still recall the thrill of learning that those beeps and dits were from people all over the world. That led to a life in ra
On this Saint Patrick's Day, let those of us so inclined raise a glass of Jameson's to Guglielmo Marconi: We hunt for our own pot o' gold at the end of an ionospheric rainbow, enjoying radio that owe
From W6NL: The history of this antenna begins with my 2003 antenna with 27-foot boom, designed for our 125 mi/h (200 km/h) winds. See https://www.kkn.net/dayton2004/dayton-2004-antenna-forum.html Thi
It goes without saying, but I'll repeat it anyway: For antenna or tower use, avoid the eye bolts that are just bent in a circle, only use the ones that are forged as a solid ring. Same for seat-belt
I've had the same reliability issue with prop-pitches, tried using heavier water-proof grease made for trailer axles with some success. I sent a dozen or so prop-pitch "cores" to Kurt before he passe
A few thoughts on this: 1. Yes, the wind force on a cylinder is essentially perpendicular to its axis. See for example https://www.kkn.net/dayton2007/w6nl_ant.pdf So the maximum twisting force (torqu
Thanks for the link to the very detailed Weber papers. They clarify the issue. The effect is even bigger for side-mounted antennas, say on a rotating tower. The calculations are based on the assumpti
Yep, it works as you suggest, have used it here and in HC8. Because the 40m band is a narrower percentage width, it takes only a half-wavelength 50-ohm line, plus the quarter-wave transformer, to cov