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  2. Amateur radio satellite - Wikipedia

    en.wikipedia.org/wiki/Amateur_radio_satellite

    e. An amateur radio satellite is an artificial satellite built and used by amateur radio operators. It forms part of the Amateur-satellite service. [ 1 ] These satellites use amateur radio frequency allocations to facilitate communication between amateur radio stations. Many amateur satellites receive an OSCAR designation, which is an acronym ...

  3. Amateur radio - Wikipedia

    en.wikipedia.org/wiki/Amateur_radio

    The amateur radio service (amateur service and amateur-satellite service) is established by the International Telecommunication Union (ITU) through the Radio Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual station licenses with a unique identifying call sign , which must ...

  4. History of amateur radio - Wikipedia

    en.wikipedia.org/wiki/History_of_amateur_radio

    Beginnings. Amateur radio came into being after radio waves (proved to exist by Heinrich Rudolf Hertz in 1888) were adapted into a communication system in the 1890s by the Italian inventor Guglielmo Marconi. [6] In the late 19th century there had been amateur wired telegraphers setting up their own interconnected telegraphic systems.

  5. Communications satellite - Wikipedia

    en.wikipedia.org/wiki/Communications_satellite

    t. e. A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military ...

  6. Amateur radio repeater - Wikipedia

    en.wikipedia.org/wiki/Amateur_radio_repeater

    Coaxial cavity RF filter at 2 meter repeater. An amateur radio repeater is an electronic device that receives a weak or low-level amateur radio signal and retransmits it at a higher level or higher power, so that the signal can cover longer distances without degradation. Many repeaters are located on hilltops or on tall buildings as the higher ...

  7. OSCAR 1 - Wikipedia

    en.wikipedia.org/wiki/OSCAR_1

    OSCAR 1 (Orbiting Satellite Carrying Amateur Radio 1, also known as OSCAR 1) is the first amateur radio satellite launched by Project OSCAR into low Earth orbit. OSCAR I was launched December 12, 1961, by a Thor-DM21 Agena B launcher from Vandenberg Air Force Base, Lompoc, California. The satellite, a rectangular box (30 x 25 x 12 cm) weighing ...

  8. Amateur radio frequency allocations - Wikipedia

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

    Historically, amateur stations have rarely been allowed to operate on frequencies lower than the medium-wave broadcast band, but in recent times, as the historic users of these low frequencies have been vacating the spectrum, limited space has opened up to allow for new amateur radio allocations and special experimental operations.

  9. AMSAT-OSCAR 7 - Wikipedia

    en.wikipedia.org/wiki/AMSAT-OSCAR_7

    AMSAT-OSCAR 7 (AO-7) AMSAT-OSCAR 7, or AO-7, is the second Phase 2 amateur radio satellite constructed by the Radio Amateur Satellite Corporation (AMSAT). It was launched into Low Earth Orbit on November 15, 1974 and remained operational until a battery failure in 1981. After 21 years of apparent silence, the satellite was heard again on June ...