When using a G5RV as a T-antenna the balun at the ladder line to coax transition should be removed. Dave WX7G _______________________________________________ Topband reflector - topband@contesting.co
W8JI solved another problem and saved someone much time and frustration. I'd like to thank Tom for the great help and knowledge he has imparted in me and many, many others over the years. In my exper
A UHF connector won't flash over at 1500 watts if the VSWR is low. _______________________________________________ Topband reflector - topband@contesting.com
To me each of the three 160 meter contests has its unique charm. The Stew Perry 'test tends to level the playing field. The 15 hour operating limit is easier on the mind and body. *I would LOVE to se
N6VW reports driving 5 watts into his apartment plumbing against the AC system ground and making a couples dozen QSOs in the 'test. _______________________________________________ Topband reflector -
Carl, Tree and all the rest I find it fascinating how just about any piece of random metal and low power will yield top band contacts. For the Stew Perry I propose an award for *"lamest antenna*" or
A way to bring back the DX Window is to not work US stations who call CQ in the window. Boycott them if you will. Dave WX7G _______________________________________________ Topband reflector - topband
20 dB implies that the ground system loss is 10X the inverted-L radiation resistance. This would result in an input resistance of 250 ohms and a minimum VSWR if 5:1. I don't think that is what the re
Correction, 100X the loss. The deal difference between a single ground rod and a BC station ground will be about 6 dB. _______________________________________________ Topband reflector - topband@cont
Guy, you make it sound like magic. See the IEEE paper RADIATION EFFICIENCY AND INPUT IMPEDANCE OF MONOPOLE ELEMENTS WITH RADIAL-WIRE GROUND PLANES IN PROXIMITY TO EARTH ______________________________
Guy, here is where I believe your mysterious extra "loss" in NEC is coming from. You are reading the "average gain" loss. NEC calculates that by integrating the power at infinity and dividing by the
Some of us have little choice for low band antennas. I am currently using a Tarheel 200A screwdriver antenna with a 24' whip in an HOA neighborhood. That gives me a 30' base loaded vertical over 90 r
That is quite an improvement. I had to have dropped the base impedance from 400 ohms to 40 ohms for it to do that. Dave WX7G _______________________________________________ Topband reflector - topban
Read the N6LF radial papers and you will see that 1/8 wavelength radials are about as good as one can do. I use #14 stranded copper THHN wire because it is easy to work with. But how good can we get?
Mike that QTH looks alot like the Great Salt Lake of Utah where I have operated a few 160 meter 'tests running a balloon vertical. Dave WX7G _______________________________________________ Topband re
Don, a 36" helium balloon filled to 32" is enough to lift 130' of #26 wire in no wind. It doesn't take much wind to blow it horizontal. A half wave vertical suffers more as it is blown down so I thin
The 10 dB, or was it 20 dB, claim could be a case of "belief preservation" as described in section 3.5 of the paper *Teaching Critical Thinking: Lessons for Cognitive Science*, by Tim van Gelder http
Tom, I think you are extrapolating one case with a particular radial length to all vertical antenna ground systems. The N6LF radial papers detail his NEC-4 simulations and measurements of vertical an
*Half wavelength vertical ground loss* Let's see if we can quantify the conduction losses of a 1.8 MHz half wavelength vertical connected to average earth via a ground rod. This paper by N6LF shows o