How would you guys who are stuck in an endless thread of loading coils like
to take on 'linear loading'?? are the currents the same at each end of the
loading line?? do they cancel completely along the length of the loading
line? does the loading line replace so many degrees of the length of the
elements or cause some kind of delay???

the antenna i am working on is an m-squared 40m4lldd where, for example, the
reflector is 50' tip to tip, about 10' out from the boom there is an
insulator, a rod about 9' long connects with a metal bracket on each side of
the insulator and folds back toward the boom where they are connected with
an aluminum shorting bar that then uses a piece of phillystrand that goes to
an element truss support bracket. then of course beyond the insulator is
another 15' or so of element, the tips are adjusted to tune the elements.

"John - KD5YI" wrote in message
news:uP70g.270$_s5.47@trnddc04...
Dave wrote:
How would you guys who are stuck in an endless thread of loading coils
like to take on 'linear loading'?? are the currents the same at each end
of the loading line?? do they cancel completely along the length of the
loading line? does the loading line replace so many degrees of the
length of the elements or cause some kind of delay???

the antenna i am working on is an m-squared 40m4lldd where, for example,
the reflector is 50' tip to tip, about 10' out from the boom there is an
insulator, a rod about 9' long connects with a metal bracket on each side
of the insulator and folds back toward the boom where they are connected
with an aluminum shorting bar that then uses a piece of phillystrand that
goes to an element truss support bracket. then of course beyond the
insulator is another 15' or so of element, the tips are adjusted to tune
the elements.



What's "linear loading"? What's a "loading line"?

i probably didn't do a very good job of describing it, but basically you
take a shorter than 1/4 wave element and cut it in the middle somewhere and
put in an insulator. instead of putting in a loading coil as you would
normally expect you use a shorted piece of parallel wire line to tune it.
in the case of the 40m4lldd the parallel wire line is made of aluminum rod
and is folded back to use it as a truss for the element.

"Dave" wrote in message
...

"John - KD5YI" wrote in message
news:uP70g.270$_s5.47@trnddc04...
Dave wrote:
How would you guys who are stuck in an endless thread of loading coils
like to take on 'linear loading'?? are the currents the same at each
end of the loading line?? do they cancel completely along the length of
the loading line? does the loading line replace so many degrees of the
length of the elements or cause some kind of delay???

As far as acting as loading element, it is another form of (real life)
loading inductance, so it is similar to loading coil, but worse performer in
the loaded Yagi situation. Have look at the end of my article
http://www.k3bu.us/loadingcoils.htm
where EZNEC plot shows current distribution along the loaded Yagi element,
using loading stubs.

the antenna i am working on is an m-squared 40m4lldd where, for example,
the reflector is 50' tip to tip, about 10' out from the boom there is an
insulator, a rod about 9' long connects with a metal bracket on each
side of the insulator and folds back toward the boom where they are
connected with an aluminum shorting bar that then uses a piece of
phillystrand that goes to an element truss support bracket. then of
course beyond the insulator is another 15' or so of element, the tips
are adjusted to tune the elements.



What's "linear loading"? What's a "loading line"?

i probably didn't do a very good job of describing it, but basically you
take a shorter than 1/4 wave element and cut it in the middle somewhere
and put in an insulator. instead of putting in a loading coil as you
would normally expect you use a shorted piece of parallel wire line to
tune it. in the case of the 40m4lldd the parallel wire line is made of
aluminum rod and is folded back to use it as a truss for the element.


It has been found and published in articles in CQ magazine, where loading
stubs were replaced by the loading coils and the performance of the antenna
like KLM 80m 3 el. loaded Yagi was improved significantly. Better gain and
better and cleaner F/B and pattern. Real modeling and measurements confirmed
that, regardless what the "flat earth - same current" believers claim and
try to "prove".
Folding the loading stubs along the elements seems to distort the current
distribution along the element and deteriorate its' performance. So you are
better off replacing loading stubs with loading coils, and that's what the
whole debate about the current distribution, reality and understanding it is
about.

73 and GL Yuri, K3BU.us

On Sat, 15 Apr 2006 12:06:45 -0400, "Yuri Blanarovich"
wrote:

it is similar to loading coil, but worse performer in
the loaded Yagi situation. Have look at the end of my article
http://www.k3bu.us/loadingcoils.htm

Hi Yuri,

As usual, your statement has nothing to do with your link. What is
worse, this EZNEC model is from a third party who is not available to
comment as to the accuracy of your statements about performance.

Even more is the compounding of error at the link:
"G5RV antenna using inductors in the form of loading stubs"
Clearly, then, it is NOT a G5RV.

When we continue with the commentary we find:
"When simple inductance in Eznec is inserted in place of the
stubs, the current erroneously is shown as the same at the both
ends of the inductor."
Clearly, then, the model designer who expected something other does
not know how to design the model. It would seem after several years
of corrections to this error you continue to publish, that you would
have updated your page by now.

It is easy to offer broken solutions. This group sees many of them
that are then used to discredit either the tool or the theory. What
these broken models reveals are the bankrupt designer.

Perhaps you should vet the material from your contributors more
closely.

73's
Richard Clark, KB7QHC

Hi Richard,
I thank you for posting such revealing evaluation of my deficient,
misleading knowledge.
Yes, my web site is full of old no good stuff. Even my C6AYB picture is too
many pounds old.
Anyone with spec of antenna knowledge can see that "G5RV" is operated as
dipole, judging by the standing wave current distribution, and it is not
cardinal sin to call it G5RV dipole or vice versa.
If I can get away from deflecting mumbo-jumbo and over holidays, I will
start working on the project. Looks like audience here is looking for
sticking needles rather than providing answers and suggestions to questions.
The main thrust of question posted here was, should he stay with loading
stubs or do something better. I described what was done, and stubs suck,
coils are MUCH better and that current distribution is what it is and
illustrated in that "butchered" drawing by W5DXP.
I humbly bow in view of your much better, educational posting. I am sure the
questioner is fully satisfied with your answers and solutions.

Happy Easter from bankrupt designer

73 Yuri, K3BU

"Richard Clark" wrote in message
...
On Sat, 15 Apr 2006 12:06:45 -0400, "Yuri Blanarovich"
wrote:

it is similar to loading coil, but worse performer in
the loaded Yagi situation. Have look at the end of my article
http://www.k3bu.us/loadingcoils.htm

Hi Yuri,

As usual, your statement has nothing to do with your link. What is
worse, this EZNEC model is from a third party who is not available to
comment as to the accuracy of your statements about performance.

Even more is the compounding of error at the link:
"G5RV antenna using inductors in the form of loading stubs"
Clearly, then, it is NOT a G5RV.

When we continue with the commentary we find:
"When simple inductance in Eznec is inserted in place of the
stubs, the current erroneously is shown as the same at the both
ends of the inductor."
Clearly, then, the model designer who expected something other does
not know how to design the model. It would seem after several years
of corrections to this error you continue to publish, that you would
have updated your page by now.

It is easy to offer broken solutions. This group sees many of them
that are then used to discredit either the tool or the theory. What
these broken models reveals are the bankrupt designer.

Perhaps you should vet the material from your contributors more
closely.

73's
Richard Clark, KB7QHC

On Sat, 15 Apr 2006 21:44:55 -0400, "Yuri Blanarovich"
wrote:

Hi Richard,
I thank you for posting such revealing evaluation of my deficient,
misleading knowledge.

Hi Yuri,

Your appreciation is well placed.

Anyone with spec of antenna knowledge can see that "G5RV" is operated as
dipole, judging by the standing wave current distribution, and it is not
cardinal sin to call it G5RV dipole or vice versa.

Anyone? No, this is embracing a crowd to insulate you from
sloppiness. You rail about accuracy, bewail efficiency, demand
perfection, and this is your defense? It works better in a teenager's
diary - not here.

If I can get away from deflecting mumbo-jumbo and over holidays, I will
start working on the project. Looks like audience here is looking for
sticking needles rather than providing answers and suggestions to questions.

More sobbing. Yuri, if "doing" this had anything to offer you, you
would have done it by now. Others, including myself, have already
posted results, answers and suggestions. We merely wait for you to
either catch up, or pass us.

In light of the many promises of more horsepower, faster acceleration,
and better gas mileage, that has been a long wait.

The main thrust of question posted here was, should he stay with loading
stubs or do something better. I described what was done, and stubs suck,

Suck goes right up there with BS that is sold for a dime a truck full.
coils are MUCH better

How much better? This sounds like a fractal sales pitch.

and that current distribution is what it is

Zen and BS depress the price to a nickel a truck load.

and illustrated in that "butchered" drawing by W5DXP.

This confirms my comment that you should vet your references closer.

I humbly bow in view of your much better, educational posting. I am sure the
questioner is fully satisfied with your answers and solutions.

Not something I would take for granted. You have to careful about
being humble, I whip peasants for fun too.

73's
Richard Clark, KB7QHC
protecting the world against fractal salesmen for 10 years.

"Richard Clark" wrote

How much better? This sounds like a fractal sales pitch.


Your HOW MUCH is getting a bit TOO MUCH!
Comparing this to fractal sales pitch??? That is TOO MUCH!
Go read the article in CQ magazine if you like to find out details. Geeez!
Guy asked question, I gave some answer, better than nothing that you gave or
anyone else. If you expect me to write a book, than wait!
Looks like you got TOO MUCH time and enjoy sticking needles.
Sorry I don't write exactly as you would wish.
Get a life!

73 Yuri

On Sun, 16 Apr 2006 01:33:10 -0400, "Yuri Blanarovich"
wrote:
How much better? This sounds like a fractal sales pitch.

Your HOW MUCH is getting a bit TOO MUCH!
Comparing this to fractal sales pitch??? That is TOO MUCH!

Would it touch a raw nerve to ask how much too much is?

Go read the article in CQ magazine if you like to find out details. Geeez!

Hi Yuri,

A vanity rag? When you can't remember what you read, that has to be
the hallmark of a grand article. I bet GQ will give me better
details, I would learn to dress better too - if that mattered.

Get a life!

OK, so this is about the style of men's fashions. Do the lash marks
show through your hair shirt?

73's
Richard Clark, KB7QHC

On Sat, 15 Apr 2006 12:06:45 -0400, "Yuri Blanarovich"
wrote:

As far as acting as loading element, it is another form of (real life)
loading inductance, so it is similar to loading coil, but worse performer in
the loaded Yagi situation. Have look at the end of my article
http://www.k3bu.us/loadingcoils.htm

Hi Yuri,

Now, when we actually "look" at the design at your link, we find we
don't know much about:
1. How tall the antenna is (never said);
2. How long the radials are (never said);
3. How many turns in the coil (have to squint and count and hope);
4. How long the coil is (you gotta guess);
5. What frequency this resonates at (well, actually it doesn't say it
resonates anywhere);
6. What the drive point Z is (as if that mattered)

But we do know that some one can find
7. The current into the coil and;
8. The current out of the coil;
9. which according to breathless reports makes all the difference in
the world,

until
10. I threw away that trash coil, replaced it with a distributed load
(aka shorted transmission line) and boosted the performance.

73's
Richard Clark, KB7QHC

Dave wrote:
How would you guys who are stuck in an endless thread of loading coils like
to take on 'linear loading'?? are the currents the same at each end of the
loading line?? do they cancel completely along the length of the loading
line? does the loading line replace so many degrees of the length of the
elements or cause some kind of delay???


All of the petty arguing and self-promotion aside, linear loading is
just a very poor form of a loading coil. Like any poorly designed
system, the ill effects of design shortfalls can range from very small
to very large.

As a general rule, linear loading reduces efficiency over a lumped coil
of good design. Again the exact amount and the overall effect varies
with where the loading is placed in the antenna, how it is constructed,
and where and how the loading coil compared to it is constructed and
placed.

A transmission line, even a very good one, generally has a Q of
someplace around 20-75. The definition of Q I am using is reactance
over ESR. Say you need a reactance of 400 ohms to resonate an antenna.
Linear or stub loading would add a series resistance of 5 to 20 ohms as
loss resistance at that point in the system.

It would take a very poor coil to have that Q, but it can be done.

Depending on where in the antenna you insert that loss resistance, the
effects can be large or small. Myself, I avoid linear loading. I'm not
a person who likes to gamble.

We have now all seen first hand how a fascination with destroying
others really just destroys the ability to learn anything ourselves
and to help others learn. This loading coil thing has become a mental
illness, like uncontrolled shoplifting. One fellow wrote a nice book on
transmission lines and a long argument about amplifiers and a long
argument about reflected waves on amplifiers did the same thing.

This stuff is more a demonstration of emotional problems or mental
illness than science and education. It's one step below someone going
postal and just shooting everyone else in the world who is responsible
for his failures and unpopularity!

I hope this post gives insight into how arguing or fixations ruin the
educational process, and also sheds light on linear loading. Something
for everyone.

73 Tom