After seeing your message I found this. What do people think about these towers? http://www.onemantowers.com/ Dudley, WA1X I have heard that someone in the USA is making One Man Towers under license
I agree with those who say that modeling is a valuable place to start with a complex antenna design. Then one must translate the model results to the real world, understanding the limitations of the
Actually, in a stepper motor driven system, you only need to sense one absolute position and let the stepper motor do the relative positioning. Its an age old trick in automation. On power-up, you h
I have been following the lightning/grounding threads on this list for quite some time and have read articles and literature from ICE and PolyPhasor. Now I would like to ask some practical questions
Bryan, For years our club has used aluminum extension ladders for antenna supports on Field Day. A small number of people can stand up the unextended ladder and guy the lower section very quickly. Th
-- Also, there was an article in Ham Radio sometime in the 80s, that detailed exactly how to make a tilt-over tower out of steel tubing. It had some formulas for calculating the length and size for e
Jim, The term "600 ohm line" doesn't refer to the impedance of the line itself. In old audio systems where all the lines were balanced, the input and output impedances of amplifiers and mixers were 6
Yes, that concerns me, too. The distance between the two entry points will surely produce a difference in potential on one utility ground vs the other if one utility gets hit. And when they combine a
Mark, I can understand your confusion. You are right about the term Grid Dip Meter. It is a holdover from when everything was powered by glass bottles with grids in them. The modern ones work the sam
Jason, I have been wondering the same thing myself. I am about to call some vendors to see what they say about it. As an alternative, I believe there are some hefty clamps for this purpose. A while a
Chuck, I think you have two choices. You could do the rod bending thing as you suggested, or you could cut the ground rods in half and use twice as many of them. The rule of thumb from the Polysphaso
Scott, Scott, Yes, the literature about radials can be confusing unless you keep in mind an important distinction. In the case of an elevated 1/4 wave vertical, the main purpose of radials is to make
Tom, Yes, you are right. I think my feedpoint resistance scenario is oversimplified. But we ought to bring it back to an answer for Scott. I have a feeling he is itching to get something on the air.
Tom, Yes thanks. That last paragraph of yours puts it completely in perspective. Dudley Chapman The bottom line is you can make a real project out of it and maybe gain a couple percent, but once you
There is definitely a subjective difference between solid state and tube type audio amplifiers. But as many have indicated here, it is the artifacts that the tube type amplifiers provide that make it
Jerry, Radials on the surface do not need to be 1/4 wavelength long since they don't serve to resonate the structure like elevated radials do. They are there to improve ground conductivity only. Radi
Al, Yes, I was surprised when I happened onto the same discovery. I think it goes against intuition, but it's not really surprising once you look into it. A good way to look at is to first consider a
Keith's comment below reminded me of a question I had about horizontal ground rods on lightning protection systems. Current wisdom seems to suggest that if it is impossible to drive ground rods verti
Gary, Thanks for those comments. Yes, driving rods down into the soil is the best thing, of course. But say you had to lay a perimeter ground in sandy soil that was on top of bedrock only a few feet
More important, how do you properly ground a plastic owl for RF, Lightning, and electrical safety. Do you need a single point owl? How do you calculate the wind load of a plastic owl? Jim Idelson K1I