Loading Coils in 20th ARRL Antenna Book
 

Just got the 20th edition of ARRL Antenna Book and the "thing" about current in
loading coils is perpetuated in it.
Actually, book contradicts itself. On page 16-4 Fig 7 shows rough current
distribution with center loading, showing drop across the coil.
On page 16-7 Fig 10 "sticks" to no drop in current across the coil, proclaims
"stretching" the current by the coil. The shaded area is back, it actually
represents the current coming out of the coil, but the reality is lost in the
formulas.
My experiments were grounded by lousy stormy weather and flu, mybe I get the
web page spruced up.

Merry Christmas everybody, that includes Art!

Yuri

Yuri Blanarovich wrote:

Just got the 20th edition of ARRL Antenna Book and the "thing" about current in
loading coils is perpetuated in it.
Actually, book contradicts itself. On page 16-4 Fig 7 shows rough current
distribution with center loading, showing drop across the coil.
On page 16-7 Fig 10 "sticks" to no drop in current across the coil, proclaims
"stretching" the current by the coil.

That's what happens when someone gets seduced by the steady-state model
and ignores the component forward and reflected waves.

What is important is the delay (phase shift) through the coil. That delay
can be measured in a circuit without reflections and then applied to a
network with reflections.

A little deductive reasoning should resolve the issue. Assume the current
is unchanged through the loading coil feeding a 6 ft stinger on 75m. That
6 ft stinger has a certain impedance. So if the current out of the coil
is high, the voltage out of the coil must also be proportionally high. That
would increase the voltage at the end of the stinger. Is the voltage at
the end of the 6 ft stinger very much higher than the voltage at the end
of a 1/4WL monopole driven by the same power?
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

A little deductive reasoning should resolve the issue.

It strikes me that the "flat earth" er, equal current society arguing that coil
MUST have the same current going in and out, must have a problem then with the
extreme case of coil - stretched wire, which must have even more "samer"
current at its ends. :-)
I like the statement on the cover of ARRL Antenna Book: "The ULTIMATE reference
for Amateur Radio antennas, transmission lines and propagation"


Yuri

Yuri Blanarovich wrote:
I like the statement on the cover of ARRL Antenna Book: "The ULTIMATE reference
for Amateur Radio antennas, transmission lines and propagation"

But Yuri, shouldn't an "ULTIMATE reference" contain both sides
of the issue? :-)
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

"Cecil Moore" wrote in message
...
Yuri Blanarovich wrote:
I like the statement on the cover of ARRL Antenna Book: "The
ULTIMATE reference
for Amateur Radio antennas, transmission lines and propagation"

But Yuri, shouldn't an "ULTIMATE reference" contain both sides
of the issue? :-)
--
73, Cecil http://www.qsl.net/w5dxp


Was the previous edition of the ARRL Antenna Book the penultimate
reference?

Frank Dresser

Cecil,

If it is the "ultimate reference" there is no need for multiple points of view.
Everything contained in the ultimate reference will be complete, correct, and
indisputable.

Sorta like RRAA.

73,
Gene
W4SZ


Cecil Moore wrote:
Yuri Blanarovich wrote:

I like the statement on the cover of ARRL Antenna Book: "The ULTIMATE
reference
for Amateur Radio antennas, transmission lines and propagation"


But Yuri, shouldn't an "ULTIMATE reference" contain both sides
of the issue? :-)

Gene Fuller wrote:
If it is the "ultimate reference" there is no need for multiple points
of view. Everything contained in the ultimate reference will be
complete, correct, and indisputable.

Guess there's no such thing as an "ultimate reference", eh?
Some physicists are questioning whether time really exists.
If time doesn't exist, then all of our something per second
measurements are bogus and current magnitude becomes moot.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

On Sat, 20 Dec 2003 13:07:05 -0600, Cecil Moore
wrote:

Gene Fuller wrote:
If it is the "ultimate reference" there is no need for multiple points
of view. Everything contained in the ultimate reference will be
complete, correct, and indisputable.

Guess there's no such thing as an "ultimate reference", eh?
Some physicists are questioning whether time really exists.
If time doesn't exist, then all of our something per second
measurements are bogus and current magnitude becomes moot.

Every thing is relative.

You can measure in handsprings per furlong as long as at least two
people can agree on the terms.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair?)
www.rogerhalstead.com
Return address modified due to dumb virus checkers

Cecil Moore wrote in message
Some physicists are questioning whether time really exists.
If time doesn't exist, then all of our something per second
measurements are bogus and current magnitude becomes moot.

Time as we deal with it, is a man made measurement system. Time in
itself is infinite. So in a way, it doesn't exist. I imagine the
earliest notice of "time" was noticing the sun rises and sets at a
regular period. An "hour" could have been anything. But the
sun/moon/seasons led to the basic time structure we now use. The
measurements are not bogus to us because they are compared to our man
made reference system. But they might be bogus to an alien from
another galaxy who knows of no such reference... :/ MK