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resources, there is an international prohibition against the use of class B damped wave radio emissions (except in the USA under Part 15: "§15.521 Technical requirements applicable to all UWB devices. (i) The prohibition in §2.201(f) and 15.5(d) of this chapter against Class B (damped wave)
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in 1938. However the definition of "damped waves" in these regulations is unclear when applied to modern technology, and recently there have been moves to amend this prohibition to exempt emerging radio technologies such as
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individual nations enforce this prohibition in their communication laws. In the United States this is implemented in regulations of the
Federal Communications Commission:
27:. In this graph, the vertical axis is the amplitude of the wave, in units such as voltage or electric field strength; the horizontal axis is time.
82:) which interferes with other radio transmissions. Because of their potential to cause interference and their resulting wasteful use of
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emissions does not apply to UWB devices operating under this subpart."), established by the
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A complete listing with photos of damped wave telegraph keys (spark keys) by manufacturer.
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63:. Damped waves were the first practical means of radio communication, used during the
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FCC rules where "Type B damped wave emissions" are forbidden.
179:. United States printing office website. December 14, 1984
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A series of damped waves, such as would be radiated by a
208:. US Federal Communications Commission. August 20, 1998
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it is now generally referred to as "Class B" emission.
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51:. Information was carried on this signal by
144:Siwiak, Kazimierz; McKeown, Debra (2004).
150:. USA: John Wiley and Sons. p. 15.
47:) which consisted of a series of damped
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55:, turning the transmitter on and off (
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78:and generate electrical "noise" (
67:era which ended around 1920. In
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80:electromagnetic interference
16:Type of spark gap modulation
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229:Sparks Telegraph Key Review
177:Code of Federal Regulations
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126:Types of radio emissions
35:was an early method of
251:Radio modulation modes
59:) to send messages in
45:spark gap transmitters
39:produced by the first
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25:spark-gap transmitter
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206:ET Docket No. 98-153
121:Amplitude modulation
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210:. Retrieved
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49:radio waves
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61:Morse code
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76:bandwidth
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100:See also
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202:(PDF)
185:2018
152:ISBN
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
