7.8 Hertz Resonant Circuit

[tim123]

Hi Tim
See: https://en.wikipedia.org/wiki/Schumann_resonances

Hi Groundloop,
  ok, found it:

"The real Earth–ionosphere waveguide is not a perfect electromagnetic resonant cavity. Losses due to finite ionosphere electrical conductivity lower the propagation speed of electromagnetic signals in the cavity, resulting in a resonance frequency that is lower than would be expected in an ideal case, "

Oh, no that's back to front... 7.83 is a higher frequency than 7.14. Hmmm, so - no that's not it then...

Which part of the page do you think explains the phenomena?

Regards, Tim

[Groundloop]

Hi Groundloop,
  ok, found it:

"The real Earth–ionosphere waveguide is not a perfect electromagnetic resonant cavity. Losses due to finite ionosphere electrical conductivity lower the propagation speed of electromagnetic signals in the cavity, resulting in a resonance frequency that is lower than would be expected in an ideal case, "

Oh, no that's back to front... 7.83 is a higher frequency than 7.14. Hmmm, so - no that's not it then...

Which part of the page do you think explains the phenomena?

Regards, Tim

Tim,

Consider the distance between earth surface and the top of the Ionosphere as a waveguide.
Then use your math to find the frequency based on the thickness of the waveguide.

GL.

[tim123]

Tim,
Consider the distance between earth surface and the top of the Ionosphere as a waveguide.
Then use your math to find the frequency based on the thickness of the waveguide.

Hi GL,
  - distance between earth surface and the top of the Ionosphere  = 600Km
- a waveguide of 600 Km has a cutoff frequency of about 250Hz

I'm no wiser... Would you mind giving a full explanation?

[Groundloop]

Hi GL,
  - distance between earth surface and the top of the Ionosphere  = 600Km
- a waveguide of 600 Km has a cutoff frequency of about 250Hz

I'm no wiser... Would you mind giving a full explanation?

Hi Tim,

Quote:

"The fundamental mode frequency for Schumann resonance
is a standing wave in the Earth–ionosphere cavity with
a wavelength equal to the circumference of the Earth."

End quote.

My personal view is that the above conclusion is not correct.
I do not think that the cavity theory explains the observed reality.

The theoretical frequency is found to be 7,48Hz.

(The circumference of the earth at the equator is 40075,16 kilometers.
Speed of light, c = 299792458 meters per second.
Frequency = 299792458 / 40075160 = 7,48 Hz.)

The real frequency measured is 7,83Hz. When a real measurement
is different from the predicted theoretical value, then one must
conclude that the theory is wrong.

My theory is that the observed frequency is the result of reflections
of radio frequency energy from the different layers in the Ionosphere
and that some ELF frequencies more easy can be reflected.

So the RF energy from the lightning is radiated away, and most of
the RF is converted to heat by atmospheric damping. For some frequencies
the damping is less and the signal can be reflected back and forth between
the layers. This frequency happens to be 7,83Hz.

I have not studied the Schumann resonance in detail, and I'm not a Phd.
Maybe some other forum members can offer a explanation to why the
measured result frequency is different from the predicted one.

GL.

[tim123]

When a real measurement is different from the predicted theoretical value, then one must
conclude that the theory is wrong.

Agreed.

I like your theory, but the observed frequency remains something of a mystery...

I suppose I'll just have to put it on the back-burner, and see what turns up...