Gyro rotation, first described by Micheal Faraday, is clearly described in
almost any standard radio engineering textbook. To quote from Terman's Radio
Engineers Handbook, 1943 edition: Page 711, first paragraph:
"The electrons in the ionosphere exist in the presence of the earth's
magnetic field. Such a magnetic field exerts a force on a moving electron
that is proportional to the instantaneous velocity of the electron, and to
the component of the magnetic field at right angles to the direction of
motion. The direction of this force is at right angles to the direction of
motion of the electron, and to the component of the magnetic filed producing
the deflecting effect. (follows an extended description of gyro frequency and
its effect on electrons and radio waves that propagate in an ionized medium.)
This trend continues until at a frequency termed the gyro frequency and
having a value of approximately 1.4 mc (mHz), the electron vibrates in a
spiral path... in which the velocity becomes increasingly great...."
"It will be noted that in all cases where the magnetic filed of the earth has
an influence, the effect is to cause the vibrating electrons to have some
motion at right angles to the direction of vibration that would exist in the
absence of a magnetic field. The polarization of the fields reradiated by the
vibrating electrons will hence differ from that of the passing wave, causing
the polarization to be affected by the presence of the earth's magnetic
field."
Terman continues at length, through page 723, with an extended explanation
and mathematical explication of what I have already stated more briefly. I
commend anyone who really wants to know to a book on propagation - with the
observation that it would be well to make at least a brief survey of optics,
since it seems some confusion between the behaviour of light "wavicles" and
UHF and VHF radio waves has arisen.
And for my part enough is enough.
73 Pete Allen AC5E
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