Hobbie & Craft Article:
Radio Controlled Hobbies: A Technological History
You push a lever on your remote, and your remote control plane veers to the left. It almost seems like magic. Radio control is one of the most magical inventions of the modern era. It has a very long and intriguing history.
Linguistic research into the origins of the word radio reveals that it was from the prefix "radio-"meaning concerned with radiations. The word radio came into being before Hertz's discovering of electromagnetic radiations. Initially what was radio-telegraphy and radio-telephony over time came to be just radio. One of the first people to popularize the term was another pioneer in America in the field of wireless transmission: Dee Forest.
Tesla demonstrated wireless telegraphy in 1893 almost eight years after the discovery of the electromagnetic waves by Hertz. Jagdish Chandra Bose in 1894 used electromagnetic waves to ignite gun powder and strike a gong in Calcutta (Now Kolkatta) in India. That possibly was the dawn of wireless/radio communications and its applications in science. Tesla in 1896 transmitted wireless signals for nearly 30 miles distance and patented his first four tuned circuit wireless system as being the first practical wireless transmission equipment. Marconi in 1899 spanned the English channel with this wireless transmission.
The dawn of the new century also was the beginning of a new era when Marconi performed the first trans-Atlantic radio signal in 12th December, 1901. The crystal sets which were patented by J.C. Bose came to be commonly used for detecting and receiving radio signals. There have been numerous disputes over who exactly was the first to conceive the idea or wireless transmission, Tesla or Marconi. In between somewhere there is one Popov who was also a pioneer in this field! Tesla is said to have run into financial troubles that greatly limited his run in the race. But nevertheless, Tesla seems to have been the first, but the controversy over this is not our concern now. Whoever it was, the truth stands is that it was one of the finest inventions in the history of science.
The first decade of the century saw many entrepreneurs and experimenters working with wireless radio but it was about at the near end of the first decade that definite hobby interests sparked. Radio signals were originally produced by spark transmitters, which were noisy and inefficient. Then the alternator-transmitter and then the arc-transmitter came into being.
The invention of vacuum-tude diodes and triodes revolutionized the radio transmission and receivers. The invention of triode amplifier generators made audio possible and started a new era of "audio radio". The vacuum tubes were the staple component for a long time until the invention of the transistor which made the equipment more precise, concise and efficiently mobile!
Then, AT&T used the vacuum tubes to transmit voices over phone lines and this lead to the experimenting of speeches over long distances for audience to hear over loudspeakers. Commercialization was thought about from the initial days but there was no way to restrict the transmission to specific paid users and broadcasting remained commercial-free. Then AT&T started the idea of advertising to finance the programming, and it is here to stay until this very date. There have been constant innovations in the field of radio broadcasting with the latest craze being internet radio. So, radio is NEVER out of date but it is forever coming in new forms.
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