[Antennas] Re: Painting Antennas and Fiberglass Spreaders for Quads

[Barry L. Ornitz]

Unable to argue on the technical merits, Steve, W1GOR, ranted 
the following:

> Your response, albeit interesting, reminds me of a fellow 
> whom I knew many years ago... He was the type who, when 
> asked, "what time is it..?", would respond with a lengthy 
> lesson on quantum physics and celestial mechanics...,
> when all I wanted was the correct time...!

I have found most readers here actually wish to learn some 
science behind their hobby.  If you do not, that is certainly 
your right.  There was nothing wrong with the website you 
suggested except that it made it sound like there was only one 
exact type of paint that could be used which is certainly not 
the case.
 
> BTW, the manufacturers of these vertical antennas DO refer 
> to the housings as RADOMES, so that's why the article also 
> used the term RADOME.  

That does not make them right.  :-)   The definition I used is 
basically that given in Chapter 44, Radomes, in Johnson and 
Jasik's "Antenna Engineering Handbook, 2ed."  The distinction 
is important in this discussion for the reasons I listed.  
Quoting from the book,

"Radome effects can be qualitatively explained and understood 
in terms of TEM (plane) wave propagation through and 
reflection from planar dielectric panels.  The curved radome 
wall is considered to be locally plane at each point.  Waves 
emanating from the enclosed transmitting antenna are also 
considered to be locally plane at each point of incidence on 
the radome wall.  The reflected and transmitted waves can then 
be approximated from plane-sheet theory, and the resultant 
effects on overall antenna performance can be calculated."

This is quite different than the situation where the insulator 
is located in the near-field (reactive field) of the antenna 
where the dielectric properties of the insulator affect the 
resonance and efficiency of the antenna itself.

>While your frequent responses are interesting, they tend 
>toward being pedantic and extreme... It would be in the 
>interest of all readers for you to submit simplified 
>responses, and stick to the issue at hand, rather than 
>submitting a professional resume along with your comments... 

No, just SOME readers.  These are the people who ask "is a 
vertical better than a long wire" without ever understanding 
why the answer depends on a myriad of conditions.

>Since my professional credentials are similar to yours, I 
>find that the best response is one that addresses the 
>majority of readers.  

I seriously doubt the first statement.  While my Ph.D. is in 
chemical engineering, I have taken graduate courses in 
antennas and transmission lines, integrated circuit 
manufacturing and basic semiconductors.  My industrial work 
was primarily in online instrumentation, but I was the Eastman 
expert in the electrical properties of plastics and polymers.  
While I was located in the Research Laboratories, I spent 
considerable time assisting their Technical Service department 
in areas such as dielectric heating and sealing, and in 
electrical property measurements such as surface and bulk 
resistivity, insulation resistance, surface arc tracking, 
electrostatic spraying, and static electricity abatement.  
Much of Eastman's business is in providing materials to the 
paint industry, so it is natural to have to be familiar with
paint technology.

>Also, I'm not into pissing matches, because they bore the 
>hell out of me... besides, I refuse to have a 'battle-of-
>wits' with unarmed men..!

It surely sounds like you are.  Yet you have not provided any 
technical or scientific point to argue on.  Instead, you claim 
my answers are too technical and boring.  Perhaps they are for 
some readers, but then again, this is a technical hobby and I 
hope the readership will learn something of science and not go 
to the lowest common denominator of appliance operators so 
prevalent these days.  I received several encouraging notes 
from other readers about this same article on paints with 
yours being the only negative one.

Besides, this response contradicts two personal notes you sent 
me earlier this year.  In one, you noted my article was 
"interesting and informative" and then asked for a copy of my 
table of galvanic series of metals.  In the second, you 
thanked me for my explanation of the characteristic impedance 
of cables noting it was clearer than the one your professors 
taught years ago.

If you wish to debate technical points in my articles, please 
bring them up.  If you do not understand some of my points, 
ask me to explain further.  But don't expect me to answer 
questions like the "vertical versus long wire" with a one word 
answer.

        73,  Barry L. Ornitz     WA4VZQ     ornitz@tricon.net

As to misspelling you call, I apologize.  As my peripheral 
neuropathy progresses, I find touch typing to be more 
difficult.  I try to proofread everything, but I did not catch 
this error.