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  2. 40-meter band - Wikipedia

    en.wikipedia.org/wiki/40-meter_band

    A HB9XBG Full Size Vertical Antenna for the 40m-band on Simplon Pass with view to Mount Fletschhorn. The 40-meter or 7-MHz band is an amateur radio frequency band, spanning 7.000-7.300 MHz in ITU Region 2, and 7.000-7.200 MHz in Regions 1 & 3. It is allocated to radio amateurs worldwide on a primary basis; however, only 7.000-7.200 MHz is ...

  3. Shortwave bands - Wikipedia

    en.wikipedia.org/wiki/Shortwave_bands

    Shortwave bands are frequency allocations for use within the shortwave radio spectrum (the upper medium frequency [MF] band and all of the high frequency [HF] band). Radio waves in these frequency ranges can be used for very long distance (transcontinental) communication because they can reflect off layers of charged particles in the ionosphere and return to Earth beyond the horizon, a ...

  4. Amateur radio frequency allocations - Wikipedia

    en.wikipedia.org/wiki/Amateur_radio_frequency...

    The list of frequency ranges is called a band allocation, which may be set by international agreements, and national regulations. The modes and types of allocations within each frequency band is called a bandplan; it may be determined by regulation, but most typically is set by agreements between amateur radio operators.

  5. Radio spectrum - Wikipedia

    en.wikipedia.org/wiki/Radio_spectrum

    As a matter of convention, the ITU divides the radio spectrum into 12 bands, each beginning at a wavelength which is a power of ten (10 n) metres, with corresponding frequency of 3×10 8−n hertz, and each covering a decade of frequency or wavelength. Each of these bands has a traditional name.

  6. Shortwave radio - Wikipedia

    en.wikipedia.org/wiki/Shortwave_radio

    For example, in the official bandplan of the Netherlands, [34] the 49 m band starts at 5.95 MHz, the 41 m band ends at 7.45 MHz, the 11 m band starts at 25.67 MHz, and the 120 m, 90 m, and 60 m bands are absent altogether. International broadcasters sometimes operate outside the normal the WRC-allocated bands or use off-channel frequencies.

  7. Frequency allocation - Wikipedia

    en.wikipedia.org/wiki/Frequency_allocation

    Frequency allocation (or spectrum allocation) is the part of spectrum management dealing with the designation and regulation of the electromagnetic spectrum into frequency bands, normally done by governments in most countries. [1] Because radio propagation does not stop at national boundaries, governments have sought to harmonise the allocation ...

  8. Slow-scan television - Wikipedia

    en.wikipedia.org/wiki/Slow-scan_television

    Band Frequency Sideband 80 meters: 3.845 MHz (3.73 in Europe) LSB 43 meters: 6.925 MHz (pirate radio) USB 40 meters: 7.171 MHz (7.165 in Europe) LSB 40 meters: 7.18 MHz (New suggested frequency to include General Class licensees) LSB 40 meters: 7.214 MHz Australian digital SSTV frequency (Easypal and DIGTRX) LSB 20 meters: 14.23 MHz Frequency 1 ...

  9. Skywave - Wikipedia

    en.wikipedia.org/wiki/Skywave

    On October 10, the Third National Radio Conference made three shortwave bands available to U.S. amateurs [8] at 80 meters (3.75 MHz), 40 meters (7 MHz) and 20 meters (14 MHz). These were allocated worldwide, while the 10-meter band (28 MHz) was created by the Washington International Radiotelegraph Conference [ 9 ] on 25 November 1927.