Dave wrote:
Cecil --- you are begging the question!!

Of course I am, nobody knows *why* things are the way they
are. There is no 'why' built into quantum mechanics. There
is only probability. Why does one photon wind up in an
inner interference ring and one wind up in an outer
interference ring? Nobody knows.

I reported that the addition of 3 or 4 inches above the coil produces a
much larger shift in frequency than adding the exact same length below
the coil [by almost a factor of 100:1]. That is empirical data. It is
real and measurable.

My question is one of Physics. I think everyone who reads this list
knows it happens. The real question is: Why?? Why the difference in
antenna resonant frequency?

I thought my stub examples would answer that question. Anything
done below the coil affects the number of degrees subtracted
from the antenna by the bottom element to coil interface. Anything
done to the stinger affects the number of degrees added to the
antenna by the coil to stinger interface. For a given element delta
length, the number-of-degrees-added effect is greater than the number-
of-degrees-subtracted effect.

Let's take a lossless resonant electrical 1/4WL stub where Z01 = 600
ohms and Z02 = 4000 ohms.

Source-----Z01A-----+-----Z02-----+-----Z01B-----open

Let's assume that Z01A is 45 degrees and Z02 is 45 degrees.
How many degrees does Z01B have to be to make the stub an
electrical 90 degrees long? Hint: 36.5 degrees is lost at
the Z01A to Z02 junction.
--
73, Cecil http://www.qsl.net/w5dxp

Cecil Moore wrote:
Dave wrote:

Cecil --- you are begging the question!!


Of course I am, nobody knows *why* things are the way they
are. There is no 'why' built into quantum mechanics. There
is only probability. Why does one photon wind up in an
inner interference ring and one wind up in an outer
interference ring? Nobody knows.


Methinks you have left the world of deterministic Physics and moved into Quantum
Physics. Such comments do not contribute to the answer. You are not using
Quantum mechanics to try to explain to me what is happening. You are using
transmission line models. Stick to the transmission line model.

I thought antenna EM Physics was deterministic.

- - - -

your model.

You stated:

"Anything done below the coil affects the number of degrees subtracted
from the antenna by the bottom element to coil interface. Anything
done to the stinger affects the number of degrees added to the
antenna by the coil to stinger interface. For a given element delta
length, the number-of-degrees-added effect is greater than the number-
of-degrees-subtracted effect."

The 4 inch spring is approximately 0.646 degrees long at 5.3 MHz.

Original: Source-----Z01A-----+-----Z02-----+-----Z01B-----open

Case #1: Source-----Z01A-----+-----Z02-----+-0.646-+-----Z01B-----open

Case #2: Source-----Z01A-----+-0.646-+-----Z02-----+-----Z01B-----open

Z01A has not changed. Z02 has not changed. Z01B has not changed. [The L/D ratios
for these components have remained the same and the Zo of each element is
therefore the same.] The physical characteristics of 0.646 have not changed. The
Capacitance to the coil is the same in either case. Only the location has changed.

Do you claim the complex impedance of 0.646[case 1] is different from the
complex impedance of 0.646[case 2]. Why?

Or, do you claim the net Z01B + 0.646[Case 1} is now electrically longer, in
degrees, than Z01A + 0.646[case 2]. Why?

Dave wrote:
Or, do you claim the net Z01B + 0.646[Case 1} is now electrically
longer, in degrees, than Z01A + 0.646[case 2]. Why?

I already explained how to prove to yourself why those
two cases are different. Please perform the Smith Chart
gymnastics and then report your findings.
--
73, Cecil http://www.qsl.net/w5dxp

Cecil Moore wrote:
Dave wrote:
Or, do you claim the net Z01B + 0.646[Case 1} is now electrically
longer, in degrees, than Z01A + 0.646[case 2]. Why?

I already explained how to prove to yourself why those
two cases are different. Please perform the Smith Chart
gymnastics and then report your findings.

If one takes one foot of stinger and transfers it to the
base element section, the antenna length remains the same
and the resonant frequency increases. I assume you already
knew that. So of course, 0.646 is electrically longer when
it is on top of the coil than when it is on the bottom of
the coil. The Smith Chart exercise will show why that is
true.
--
73, Cecil http://www.qsl.net/w5dxp