Many hams have just gone thru an ice storm where many have lost the end
portions of their elements due to the
weight of ice. Strange thing is that many of those hams who suffered damage
are confinced that they see NO difference in their shortened antennas and a
few were adamant that the performance had IMPROVED
One local guru who had many books on radio thought that maybe the real world
was different to what he read in books!
He then took out his ARRL book and right there is said that gain of two
dipoles side by side increases gain in proportion to the spacing between the
ends of the dipole.
Since this revelation was in a book it was obvious that what other hams were
experiencing with their damaged antennas must be true. So the guru purchased
two dipole
and put them side by side and then remove the ends just as the ice storm
would and thus increased the gap between the two dipoles, which the A.R.R.L
BOOK said would produce more gain.
The guru is now befuddled
He listened to experiences in the REAL WORLD and merged it with what must
be right because it was in a BOOK but did not get all this extra gravy he
was looking for !.
What is going on between the real world and what is written in books.?
He He!
Regards
Art

Art,
Your 'local guru' should pay more attention to what
he reads. But then, he should also be able to understand
what he read. There is no virtue in misunderstanding what
you read. Unless it's the entertainment value of misreading
what you read.
'Doc

" Art Unwin KB9MZ" wrote in message news:4tBOb.94287$xy6.169075@attbi_s02...
Many hams have just gone thru an ice storm where many have lost the end
portions of their elements due to the
weight of ice. Strange thing is that many of those hams who suffered damage
are confinced that they see NO difference in their shortened antennas and a
few were adamant that the performance had IMPROVED

What type antenna? How did they test? Dunno...I think they were
imagining things..

One local guru who had many books on radio thought that maybe the real world
was different to what he read in books!
He then took out his ARRL book and right there is said that gain of two
dipoles side by side increases gain in proportion to the spacing between the
ends of the dipole.
Since this revelation was in a book it was obvious that what other hams were
experiencing with their damaged antennas must be true.

Good grief....:/

So the guru purchased
two dipole
and put them side by side and then remove the ends just as the ice storm
would and thus increased the gap between the two dipoles, which the A.R.R.L
BOOK said would produce more gain.

Uh....I guess it hasn't sunk in that he no longer has 1/2 wave dipoles
anymore.

The guru is now befuddled

I don't doubt it...

He listened to experiences in the REAL WORLD and merged it with what must
be right because it was in a BOOK but did not get all this extra gravy he
was looking for !.
What is going on between the real world and what is written in books.?

He is taking what he is reading in books, listening to hokey, most
likely untested claims from the real world, and misapplying the info
to the antennas he is testing. The book info is correct. I guess it
hasn't occurred to him to try two full half wave dipoles like the book
intends. MK

Art, KB9MZ wrote:
"What is going on between the real world and what is written in books?
He He!"

Often, execution of what`s written is done poorly. If antenna
performance on the band for which an antenna is designed improves when
part of the antenna is removed, it`s likely due to poor design or poor
implementation, or both.

Books are usually carefully done because a mistake is very exposed and
is likely to be around on view for a very long time.

Art`s quixotic quest is now for high performance in a miniature antenna.
I think he wants someone to describe it for him to patent. Such hopes
may derive from the observation that gain from parasitic elements in an
antenna is optimum with close spacing. Driven arrays such as the W8JK
also get gain from close spacing. A price is paid for close spacing.
Mutual impedance between elements (coupling) goes up. This reduces
radiation resistance and drivepoint resistance. A low radiation
resistance is less significant as a part of an antenna`s total
resistance. It hurts efficiency. A low drivepoint resistance often
requires lossy coils to match to a power source.

If shorter elements are used to try to shrink an antenna, they may have
low radiation and drivepoint resistances which cause the same
inefficiencies as closely coupled elements.

Stack elements vertically and more space is required. Place elements end
to end and they require a longer space. Put elemants in a plane for an
end-fire array and even with close spacing, more space is required.

It`s not unusual to yearn for the unattainable but it may be unrealistic
to expect an antenna which is tiny, efficient, made of ordinary
materials, and uses ordinary construction techniques.

Let`s see, if we could only replace the less effective parts of an
antenna with parts like the more effective parts---hummmm!

Best regards, Richard Harrison, KB5WZI