Search results
Results From The WOW.Com Content Network
The most common type of receiver before vacuum tubes was the crystal set, although some early radios used some type of amplification through electric current or battery. Inventions of the triode amplifier, motor-generator, and detector enabled audio radio.
John Hays Hammond Jr. and Sr., 1922. John Hays Hammond Jr. (April 13, 1888 – February 12, 1965) was an American inventor known as "The Father of Radio Control".Hammond's pioneering developments in electronic remote control are the foundation for all modern radio remote control devices, including modern missile guidance systems, unmanned aerial vehicles (UAVs), and the unmanned combat aerial ...
Before the discovery of electromagnetic waves and the development of radio communication, there were many wireless telegraph systems proposed and tested. [4] In April 1872 William Henry Ward received U.S. patent 126,356 for a wireless telegraphy system where he theorized that convection currents in the atmosphere could carry signals like a telegraph wire. [5]
The crystal radio used a cat's whisker detector, invented by Harrison H. C. Dunwoody and Greenleaf Whittier Pickard in 1904, to extract the audio from the radio frequency signal. [9] [31] [70] It consisted of a mineral crystal, usually galena, which was lightly touched by a fine springy wire (the "cat whisker") on an adjustable arm.
In Popov's lightning detector the coherer (C) was connected to an antenna (A), and to a separate circuit with a relay (R) and battery (V) which operated an electric bell (B). The radio noise generated by a lightning strike turned on the coherer, the current from the battery was applied to the relay, closing its contacts, which applied current ...
(Before that, the most common type of receiver was the crystal set, although some early radios used some type of amplification through electric current or battery.) Inventions of the triode amplifier, generator, and detector enabled audio radio. Westinghouse buys DeForest's and Armstrong's patent.
On October 18, 1985, Nintendo released a limited batch of NES in New York City — the first time the home console was available for purchase in the U.S. 25 years later, Wired would call the NES ...
Collins became an expert in radio technology, writing many books on the subject, and conducting research on improving radio components. An unusual example were his experiments in using brain tissue to detect radio waves. [6] [7] [8] The first radio receivers prior to 1904 used a primitive device called a coherer to detect the radio waves. The ...