A wireless microphone, as the name implies, is a microphone without a
physical cable connecting it directly to the sound recording or amplifying
equipment with which it is associated. Various individuals and organizations
claim to be the inventors of the Wireless Microphone. John F. Stephens
developed an FM wireless microphone for a Navy musical show in 1951 on
the Memphis Naval base. Each of the principal players/singers had their own
microphone/transmitter. Subsequently, the Secret Service had Stephens modify
his invention to be used in government "bugging" operations. In the
''60s, Stephens marketed his more famous capstan less multi track recorder/reproducers.Shure
incorporated claim that their "Vagabond" system from 1953 was the first.
In 1957 German audio equipment manufacturer Sennheiser, at that time called Lab
W, working with the German broadcaster Norddeutscher Rundfunk (NDR) exhibited a
wireless microphone system. From 1958 the system was marketed through
Telefunken under the name of Microport.Another German equipment manufacturer, Bayer
dynamic, claim that first wireless microphone, was invented by Hung C.
Lin. Called the "transistophone", it went into production in 1962.
It
is claimed that the first time a wireless microphone was used to record sound
during filming of a motion picture was on Rex Harrison in the 1964 film My Fair
Lady. More commonly known as a Radio Microphone, there are many different
standards, frequencies and transmission technologies used to replace the microphone''s
cable connection and make it into a wireless microphone. They can transmit, for
example, in radio waves using UHF or VHF frequencies, FM, AM, or various
digital modulation schemes. Some low cost models use infrared light. Infrared
microphones require a direct line of sight between the microphone and the
receiver, while costlier radio frequency models do not. Some models operate on
a single fixed frequency, but the more advanced models operate on a user
selectable frequency to avoid interference, and allow the use of several
microphones at the same time.