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Broadcast band

The broadcast band is actually several chunks of the radio spectrum. In the U.S. the major broadcast bands are:

Common Name Frequencies Cycles/Second Modulation Band Notes
"FM"88 to 108MHzFrequency Modulation (FM)Very High Frequency (VHF) Usually music, due to the clarity and high bandwidth of FM. Relatively short range.
"AM"535 to 1700kHzAmplitude Modulation (AM)High Frequency (HF)Usually speech and news, where a lower bandwidth will suffice. Long range at night due to the ionosphere lowering in altitude.
"Shortwave"5.9 to 26.1MHzMostly FM, some AM and single-sideband (SSB) modes.HFVery long range through "skipping". Standard time frequencies can be heard here.
"Broadcast Television"54 to 88, 174 to 216, and 470 to 806MHzvestigial sideband modulation for video and FM for audioVHF and Ultra High Frequency (UHF)Channels 2 through 6 are from 54 to 88 MHz. Channels 7 through 13 are from 174 to 216 MHz. Channels 14 through 69 are from 470 to 806 MHz.

In Europe, North Africa and Asia, longwave radio frequencies between 153 and 281 kHz are used for domestic and international broadcasting.


See also

01-04-2007 01:16:19
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