{Wireless} {telegraphy or telegraph} (Elec.), any system of
telegraphy employing no connecting wire or wires between
the transmitting and receiving stations.
Note: Although more or less successful researchers were made
on the subject by Joseph Henry, Hertz, Oliver Lodge,
and others, the first commercially successful system
was that of Guglielmo Marconi, patented in March, 1897.
Marconi employed electric waves of high frequency set
up by an induction coil in an oscillator, these waves
being launched into space through a lofty antenna. The
receiving apparatus consisted of another antenna in
circuit with a coherer and small battery for operating
through a relay the ordinary telegraphic receiver. This
apparatus contains the essential features of all the
systems now in use.
{Wireless telephone}, an apparatus or contrivance for
wireless telephony.
{Wireless telephony}, telephony without wires, usually
employing electric waves of high frequency emitted from an
oscillator or generator, as in wireless telegraphy. A
telephone transmitter causes fluctuations in these waves,
it being the fluctuations only which affect the receiver.