Topband: Fw: GAP VERTICAL QUESTION

[Tom W8JI]

> This is ~true only for a "far field" analysis (as defined by NEC software)
> for a vertical monopole -- which includes the propagation losses present 
> in
> the radiated fields from that monopole, over an infinite, FLAT, real-earth
> ground plane.
>
> However that is not reality.

I think what is going here is we have a bunch of anecdotal results based on 
one unknown compromised system compared to another compromised system when 
dozens of things are changed, and we are trying to generate physics to 
support one thing as being the cause.

I am 100% sure, based on dozens of comparisons with three stations located 
not too far from me, that it is "pretty difficult" to make an antenna of 
reasonable size and construction -20dB based on ground system shortfalls.

Some of this has gone beyond reasonable or logical, and is poisoning our 
knowledge base.

In Toledo, a good friend lived on a small city lot behind a restaurant. His 
backyard, the only place for an antenna, was just a few feet deep and maybe 
100 feet long. He tied in everything he could; heating ducts, plumbing, 
short radials, a short chain link fence. He was consistently, over many 
years, within a few dB of my full size quarter wave in an ideal soil and 
ground system. This was night after night, DX or local, over and over again.

Another fellow in a neighborhood had a short TV tower with inverted L, and 
his radials ran to a sidewalk maybe ten or fifteen feet away. He had radials 
crossing the ceiling of his basement. His signal was the same way.

Another station, W8KWN, just had driven rods.

NONE of these stations were even close to 20 dB down. It was more like 5 dB 
to maybe a just little more at times, and a little less at times. The driven 
rods were the worse system, but even they were not -20 dB.

Now there was one station who had bad luck. He had bigger back yard, and it 
was just full of wires and antennas. He had all these bamboo supports and 
quads and other things, a yard full of "stuff". His signal was so weak he 
actually would swear and cuss at the other guys and accuse them of illegal 
power because his antennas "were so good" in his own mind that there was not 
way these other guys would beat him so badly unless they were cheating. No 
amount of conversation could convince him he had the problem.

In my experience, it is more about having a neat, clean, uncluttered 
installation and not doing things grossly wrong, like using coaxial stubs 
for loading inductance or packing 900 pounds of antennas into a two pound 
back yard area, than any sort of grounding issue.

The only -10 dB or -20 dB things I ever see are people who jam too much in 
small area, or have some other serious system error they created but just 
cannot see.

My ten foot tall mobile antenna with a pickup truck for a ground is about 20 
dB down from my TX antenna. If someone else has that issue with a 50 foot 
tall inverted L, they better look at something other than a compromised 
ground system. They have a more serious issue.

73 Tom