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Old September 28th 05, 05:16 PM
Richard Harrison
 
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Jim Kelley, AC6XG wrote:
"I think Farqaday stilll provides the best explanation."

Yes. Faraday showed d-c had nothing to do with wireless. It was the a-c
motivating wireless electrical coupling.

An Englishman, Faraday, constructed a transformer in 1831. He used two
isolateed coils of wire wound on the same spool. He connected a
galvanometer across one coil. He noticed a brief deflection of the
galvanometer each time he connected or disconnected a battery to the
second coil.

Joseph Henry, a professor at Albany Academy in New York was
independently making the same observations at the same time as Faraday.
When Henry got news of Faraday`s discoveries, he made no effort to claim
credit for his own work but often referred to Faraday`s discovery.

It was the change in the magnetic field which induced electricity
without a direct connection, not the value of the steady magnetic field
itself.

Same with antennas. A battery connected to an antenna sends no signal. A
varying field is required to produce a signal in an antenna.

Best regards, Richard Harrison, KB5WZI