I gave a presentation on the history of transoceanic radio communications
to the Frankford Radio Club a few days ago.
www.youtube.com/watch?v=pLN0MMxCvlc
My presentation covers radio technology development from the Maxwell's
mathematical description of electromagnetic waves in 1860-1865, Hertz's
development of a crude spark transmitter and spark receiver that proved
the existence electromagnetic waves in 1886-1888, Fessenden's hetrodyne
receiver patent in 1901, Marconi's development of two way transoceanic
high power radio spark communications from 1901 through 1907, the
development of multi-hundred-kilowatt spark, arc and electron tube
transmitters from 1906 through the 1930s, Armstrong's development of
regenerative and superhetrodyne receivers from 1913-1918, ARRL's very
successful one way transatlantic test in 1921 at about 1 MHz, the development
of military and commercial HF receiver, transmitter and antenna technology
from 1921 through the 1970s, and the development of early operational
military satellite communications capabilities from before 1960 through
the 1970s.
My presentation closes with a brief description of recent Armed Forces Day
operations on the site of the original NSS station.
Enjoy!
73
Frank
W3LPL
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