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Roy Lewallen wrote:
The current reported by EZNEC isn't referenced to source phase.

If the source phase is set to zero and I want EZNEC to reference
the antenna currents to 77 degrees, how would I go about that?
--
73, Cecil http://www.w5dxp.com

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On Mon, 17 Dec 2007 18:42:29 -0600, Cecil Moore
wrote:
The phase assigned by the user to the source obviously becomes
the default reference phase.

On Tue, 18 Dec 2007 00:53:03 GMT, Cecil Moore
wrote:
If the source phase is set to zero and I want EZNEC to reference
the antenna currents to 77 degrees, how would I go about that?

Hmm, still confused about two different phases? In all of four lines
you whip-saw from knowing it all to knowing nothing at all for what
appears to be the same phase.

At the fear of being presumptions, why don't you move the source 77
degrees along the radiator? Or insert a line 77 degrees long (which
phase?). Or insert a lumped reactance that offers 77 degrees phase
(which phase?).

This is getting fun. Who woulda thunk? :-)

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On Mon, 17 Dec 2007 17:09:50 -0800, Richard Clark
wrote:

On Mon, 17 Dec 2007 18:42:29 -0600, Cecil Moore wrote:
On Tue, 18 Dec 2007 00:53:03 GMT, Cecil Moore wrote:

I've just solved the phase duality problem!!!!!!!!! [observe above]

Set your system clock to CST when you design the
circuit/antenna/whatever and then reset your system clock to GMT
before you press the Currents button.

That should give you 90 degrees shift. Sorry, but this method only
works in cardinal points of 15 degrees. Perhaps there is some
neighboring county that uses Mars Twilight Savings Time for finer
granularity.

[These last two messages were performed as a public service to Roy,
whose newsreader e-barfz in gag reflex to fuller quotations from
Cecil.]

73's
Richard Clark, KB7QHC

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Cecil Moore wrote:

Take a look at the current reported by EZNEC and you will
understand. Until you do that, I'm afraid you will just
continue to show your ignorance.

Hint: Given a reference zero phase for the source signal,
EZNEC reports all current phases with respect to that
source phase. So either choose to understand or remain
ignorant - I just don't care which.

It's probably a matter of perspective, because from here it seems that
you are the one reporting the nonsensical results. I use Mathcad and
Sigma Plot for plotting functions like I(x,t) = Imax sin(kx) cos(wt).
Maybe you could give one of those a try.

73, ac6xg

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Cecil Moore wrote:
Gene Fuller wrote:
As usual you have twisted the question so that you can provide some
type of answer. You still have not answered the original question
posed by Keith.

What was that question? I suspect the question was irrelevant
because Keith didn't understand what phase shift I was talking
about. I also suspect that Keith is beginning to understand
what I am talking about. His silence seems a little strange.
What are you going to do when your realize you are on the
wrong side of the technical argument? Sandbag - like some
others have done and try to obscure the technical facts?

How about an answer from you? What is the phase shift through
the impedance discontinuity between Vfor1 and Vfor2 below?

--43.4 deg 600 ohm line--+--10 deg 100 ohm line--open
Vfor1--|--Vfor2

I doubt that you even know how to solve the problem. Your lack
of an answer will speak volumes.


Twist, twist, twist.

Do you also open the (black) box to see how Schroedinger's cat is doing?

73,
Gene
W4SZ

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Richard Clark wrote:
At the fear of being presumptions, why don't you move the source 77
degrees along the radiator?

I don't think that will make Roy's statement true.

Roy said:
"The current reported by EZNEC isn't referenced to source phase."
--
73, Cecil http://www.w5dxp.com

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Jim Kelley wrote:
I use Mathcad and
Sigma Plot for plotting functions like I(x,t) = Imax sin(kx) cos(wt).
Maybe you could give one of those a try.

Sorry, EZNEC doesn't use that equation. EZNEC needs a
reference phase. Roy seems to know how to make that
reference a different phase angle than the specified
source phase angle but I don't know how to do that.

Here's the plot for that equation above:

http://www.chemmybear.com/standing.html

Obviously, EZNEC cannot report those results in tabular
form.
--
73, Cecil http://www.w5dxp.com

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Gene Fuller wrote:
Do you also open the (black) box to see how Schroedinger's cat is doing?

I do whatever I need to do to solve the problem, Gene.
If I have to open the box to see if the cat is dead
or alive, that's what I will do. I do not believe in
erecting silly artificial barriers in the quest for
knowledge - and we are not talking about a quantum
physics paradox.

So let me repeat: The phase shifts at the -j567 points
in the two following 1/4WL stubs are not the same.

--43.4 deg 600 ohm line--+--46.6 deg 600 ohm line--open

--43.4 deg 600 ohm line--+--10 deg 100 ohm line--open

The phase shift at '+' in the 1st example is zero.

The phase shift at '+' in the 2nd example is 36.6 deg.
--
73, Cecil http://www.w5dxp.com

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Jim Kelley wrote:
It's probably a matter of perspective, because from here it seems that
you are the one reporting the nonsensical results.

I'm not reporting the results, Jim. EZNEC is reporting
the results. Choose the "Loads Dat" display.

http://www.w5dxp.com/coil512.ez

http://www.w5dxp.com/travstnd.gif

Have you ever even looked at those files?
--
73, Cecil http://www.w5dxp.com

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Jim Kelley wrote:
Maybe you could give one of those a try.

I'm well aware of what the math models show, Jim.

Let's say we have current probes installed at
'x' and 'y' in a 1/4WL wire. 'x' and 'y' are
30 degrees apart.

We apply a standing wave with the equation
I(xt) = Imax*cos(kx)*cos(wt)

source------------x---------------y-------------open

What will be the relative phase difference between
the current measured at 'x' and the current measured
at 'y'?

Now apply a traveling wave with the equation
I(x,t) = Imax*cos(kx+wt)

source------------x---------------y-------------load to ground

What will be the relative phase difference between
the current measured at 'x' and the current measured
at 'y'?
--
73, Cecil http://www.w5dxp.com