Let us say the radiation resistance is 12 ohms, not an unusual value for a short, top loaded vertical, which basically what an inverted-L is. With a poor ground system, the ground loss might be on t
I have heard it said many times that one should not weld the rebar cage together, but tie it together using tie wires. But I have never heard any explanation of why. What problems would be caused by
That's pretty much my take on it. I built mine almost 30 years ago, and tack welded the rebar together using a homebuilt arc welder. I don't see how that would weaken the rebar, since it didn't thor
This gigantic antenna system called Duga-3 is located near Prypiat in the Chernobyl area. It was built in the 70's as an early missile detection system (over-the-horizon radar system). It was also ca
What is so difficult about trying to match a half wave antenna, fed at one end? I have done this many times without difficulty, by using a parallel tuned circuit, with one end connected to the groun
"The problem with end feeding a half wave wire on 160 (in this case configured as an L) is that most people who operate 160 soon discover that you need an amplifier. That translates into big voltages
That's why it's a good idea right now to be hoarding all the leaded rosin-core solder you can find, particularly at flea markets, estate sales, etc, but maybe even at full retail price if that's all
Question 2: I have a 90' tower with a Tribander on top which makes it very close to a 1/4 wave for 160-m. I installed an Inverted L on this tower with 85' vertical and the Inv. L radiating efficiency
My 127' Rohn 25G tower has now been up for 29 years. I put it up myself, single-handedly. It has 4 sets of guys, each using 3/16EHS guy cable, broken up every 18' with strain insulators. I live in mi
Back in the 70's I bonded a radial system to the common point at the base of my inverted-L using ordinary lead/tin solder. I quickly discovered that the solder reacted with moist earth and almost imm
I would recommend approximately # 10 gauge solid galvanised "high tensile" fencing wire for temporary guys. It is inexpensive and available at about any agricultural supply outlet. It doesn't stretch
I would not consider any kind of fibre rope for temporary guys for several reasons already cited here. One more danger is the possibility of improper tying. That happened to me years ago putting up a
<<I am planning a 160m vertical with elevated radials, using Rohn 25G tower sections. I plan to have the tower insulated at 30' above ground. Rohn is very proud of their 25TG insulated section and I
I am looking for some 502 johnny ball insulators to use in re-guying a tower. The old insulators are the little type 500Ds, which have lasted 33 years but don't have the proper contour to correctly s
Bill W4WHW wrote: "...a point current source in the ground at some distance between two separated ground points will cause a different voltage at each ground point caused by the resistance between th
I agree that NOTHING should penetrate the concrete/soil interface. At a guy anchor, make absolutely sure the anchor rod does not come anywhere near the re-bar inside the concrete. It's not a matter o
This spring I plan to re-guy my tower. The old guy wires, which have been in place since 1981, are getting rusty enough to make me nervous. The tower is 25G, 127' tall, base insulated and used as a 1
In recent years, the guy wires on my tower have become what may be dangerously rusty, and I plan to re-guy. The tower is 127' tall with four guy levels, one every 30 feet. The rust pattern is very in
When I erected my tower 30-plus years ago, the cable clamps sold with Rohn towers were listed as 3/16 CCM, 1/4CCM, etc. In the current catalogue they are listed as 3/16 CCF, 1/4 CCF etc. The ones lis
Better still, run the OWL down through the interior of the tower. I use plexiglass strips attached to the Rohn 25G rungs, one every 10' to keep the wires properly spaced apart and at the geometric ce