
Preface to Ninth Edition
Wireless—or radio—has branched out and developed so
tremendously that very many books would be needed to describe it
all in detail. In ordinary conversation, 'radio' has come to mean
sound broadcasting, as distinct from TV' which gives pictures as
well as sound, but of course the pictures come by radio just as much
as the sound. Besides broadcasting sound and vision, radio is used
for communication with and between ships, cars, aircraft, satellites
and spacecraft; for direction-finding and radar (radiolocation),
photograph and 'facsimile' transmission, telegraph and telephone
links,
meteorological probing of the uppe ...