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Old November 16th 07, 05:12 PM posted to rec.radio.amateur.antenna
Richard Harrison Richard Harrison is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 588
Default RSGB RadCom December 2007 Issue

John Smith wrote:
"From the above, are the two in a constant state of interaction?"

On page 1 of Terman`s "Electronic and Radio Engineering":
"These waves, which are commonly called radio waves, travel with the
velocity of light and consist of magnetic and electric fields that are
at right angles to each other and are at right angles to the direction
of travel. If these electric and magnetic fields could actually be seen,
the wave would have the appearance indicated in Fig. 1-1."

Maxwell`s first field equation says that a changing magnetic field will
produce an electric field. The second equation says that a changing
electric field will produce a magnetic field.

The alternating magnetic field creates an alternating electric field in
the space surrounding it. Due to the alternation of the electric field
an alternating displacement current will exist in space, which will give
rise to another alternating magnetic field in the space surrounding the
displacement current, etc., etc., etc..

Maxwell`s proof is courtesy B. Whitfield Griffirh, Jr.`s
"Radio-Electronic Transmission Fundamentals", now in reprint by Scitech
Publidhing, Inc..

Best regards, Richard Harrison, KB5WZI