Gene Fuller wrote:
But you already knew that . .

Of course I did. "Through the coil" does NOT mean "through
the coil wire". It means "through the coil". You still uttered
a falsehood but I doubt that you will ever admit it.
--
73, Cecil http://www.w5dxp.com

Cecil Moore wrote:
Tom Donaly wrote:
No, Cecil, it's your theory. You have to provide the method and
then everyone else will decide whether or not they agree with you.
You're not chicken are you?

Actually, I wanted to see if anyone besides me could
solve the problem - no one else has.

You're chicken.
73,
Tom Donaly, KA6RUH

Cecil Moore wrote:
Tom Donaly wrote:
Actually, you got it wrong, Cecil. It's -43 degrees, which means
if you wanted to make one it would be about 317 degrees.

Tom, you are just showing your ignorance. 43 degrees
of 600 ohm line attached to 10 degrees of 100 ohm
line makes a dandy 1/4WL stub. Why are you so totally
ignorant of that fact of physics?

O.k., now prove it using standard transmission line theory.
You can say it over and over again, but if you can't give anyone
a reason to believe it, you're just blowing hot air.
73,
Tom Donaly, KA6RUH

Cecil Moore wrote:
Tom Donaly wrote:
If you know how to do it, Cecil, don't be coy about it. Just state
your case and be done with it. Since you already stated that
the total electrical length is 90 degrees, you're just asking me
to prove your point. Do it yourself, and then I'll tell you
whether I agree with you or not.

Does that mean you don't know how to do it?

I already did it on another thread, Tom. Adding 43 degrees
of Z0=600 ohm feedline to the 10 degrees of Z0=100 ohm
feedline will turn the stub into an electrical 1/4
wavelength (90 degree) open stub. And that's exactly
how base-loaded mobile antennas work.

It will, will it? I'm waiting for you to prove it. Do you
really expect it to be resonant at the right frequency?
This is getting tiresome, Cecil. I guess you think that
stating things over and over again will make them come
true. Oh, well, it's my fault. I shouldn't waste my time
trying to get blood out of a turnip.
73,
Tom Donaly, KA6RUH

Tom Donaly wrote:

...
It will, will it? I'm waiting for you to prove it. Do you
really expect it to be resonant at the right frequency?
This is getting tiresome, Cecil. I guess you think that
stating things over and over again will make them come
true. Oh, well, it's my fault. I shouldn't waste my time
trying to get blood out of a turnip.
73,
Tom Donaly, KA6RUH

You mean at the frequency where the 600 line length is 53 degrees and
the 100 line 10 degrees length ... well, I guess that already answers
your own question, doesn't it?--but then, you should have already knew
that ...

JS

Cecil Moore wrote:
Tom Donaly wrote:
No, Cecil, it's your theory. You have to provide the method and
then everyone else will decide whether or not they agree with you.
You're not chicken are you?

Actually, I wanted to see if anyone besides me could
solve the problem - no one else has.

O.K., Cecil, I finally figured out what you want to do. You want
a zero ohm input impedance, just like a 1/4 wave open stub. In that
case, you're absolutely right, the 600 ohm line should be 43.387
degrees long. If you call the 100 ohm line, line 1, and the 600
ohm line, line 2, then the criterion for what you want is:
tan(Bl1)*tan(Bl2)= Z01/Z02. This behaves sort of like a backwards,
transmission-line, Helmholtz resonator. I still don't know where you
come up with the 90 degree stuff. It isn't necessary to explain the
phenomenon, but if it waters your lawn, go for it.
73,
Tom Donaly, KA6RUH

(P.S. Check my math. Bl2 = atan((Zo1/Zo2)/tan(10)) =
atan(.166667/.17633) = 43.387.)

John Smith wrote:
Tom Donaly wrote:

...
It will, will it? I'm waiting for you to prove it. Do you
really expect it to be resonant at the right frequency?
This is getting tiresome, Cecil. I guess you think that
stating things over and over again will make them come
true. Oh, well, it's my fault. I shouldn't waste my time
trying to get blood out of a turnip.
73,
Tom Donaly, KA6RUH

You mean at the frequency where the 600 line length is 53 degrees and
the 100 line 10 degrees length ... well, I guess that already answers
your own question, doesn't it?--but then, you should have already knew
that ...

JS

I'm beginning to see why Roy plonked you, Smith, or whatever your
present pseudonym is. It looks as if you've been taking opacity
lessons from Art.
73,
Tom Donaly, KA6RUH

Tom Donaly wrote:
Actually, you got it wrong, Cecil. It's -43 degrees, which means
if you wanted to make one it would be about 317 degrees. (Actually,
I got -46.613 degrees.) Maybe you can make a length using negative
degrees, but it's tough for me to do.

What you apparently don't realize is the negative sign
simply indicates the direction on the Smith Chart of
"toward the source". This is absolutely reasonable since
we are indeed going in the direction away from the open
end of the stub toward the mouth of the stub, i.e. from
right to left if the source side is on the left.

From -j567.128 ohms to zero ohms "toward the source" is about
43.4 degrees. From -j567.128 ohms to zero ohms "toward the load"
is 316.6 degrees. Your signs are correct - you just didn't
understand what they mean.
--
73, Cecil http://www.w5dxp.com

Tom Donaly wrote:
No, Cecil, it's your theory. You have to provide the method and
then everyone else will decide whether or not they agree with you.

I appreciate your crediting me with a transmission
line theory, Tom, but after hundreds of years of
established theory, I seriously doubt that I have
discovered anything new. It is much more likely
that you slept through a few days of Fields and
Waves 301.
--
73, Cecil http://www.w5dxp.com

Tom Donaly wrote:
O.k., now prove it using standard transmission line theory.
You can say it over and over again, but if you can't give anyone
a reason to believe it, you're just blowing hot air.

Does that imply that you are incapable of verifying
it for yourself? - incapable of proving it wrong? I
went through the math in a reply to Dan and I have
verified it using MicroSmith. IMO, these dual-Z0
shortened stubs are best understood using the Smith
Chart.

Let's see how much you have learned. If we make the
600 ohm section equal in length to the 100 ohm
section, how many physical degrees of length will each
section have to be to achieve 1/4 wavelength resonance?
--
73, Cecil http://www.w5dxp.com