Thread: Why?
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Old March 28th 07, 12:39 AM posted to rec.radio.amateur.antenna
art art is offline
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First recorded activity by RadioBanter: Sep 2006
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Default Why?

On 27 Mar, 15:12, (Richard Harrison) wrote:
Art wrote:

"I have his (Kraus`) second edition (Antennas) and I find no mention of
radiation from the beginning where current is applied onward."

I think I have that edition too. If you review the chapter on "Point
Sources" you`ll find: power patterns, a power theorem and its
application to isotropic sources, rediation intensity, source with
hemispheric power pattern, unidirectional cosine power pattern, etc.,
etc..

The new, now available 3rd ed. of "Antennas" by Kraus, Marhefka, and a
host of others is greatly expanded and improved. It is worth the
investment.

Being uncertain of what Art really wants, doesn`t stop me from advising
him to start by having a look at the famous Sommerfeld formula on page
804 of Terman`s 1955 opus.
It predicts 1 kilowatt will produce 186 mv per m at a distance of 1 mile
from a short vertical transmitting antenna given a certain ground
conductivity and other conditions.

Best regards, Richard Harrison, KB5WZI


Richard, I have lots of books but as yet have not found the answer
even tho many have posted none appear to really have an answer other
than to throw stones. You apparently have found the answer! Could you
quote from the books that you are refering to the angle of radiation
relative to the radiator, thats it ? If you can't understand that then
relay to me the angle of a radiation front relative to a radiator, I'm
sure some other people are interested in what you found. Even better,
let me know the TOA of a dipole in free space and how much it varies
to that of the same dipole over a perfect ground. Use a computor
program if you like, anything that sheds light on the matter . The
books say that a horizontal "v" antenna should be tipped for max gain,
doesn't that raise your interest about the reasoning and mathematics
behind this? Jimmie D asked me to state this angle but I have only a
expensive computor program that doesn't give the math with the answer.
Please read off the angle and the specifics so we all can move on, I
don't want a 160 thread postings some thrust upon Walt
Art