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  2. 1951 USAF resolution test chart - Wikipedia

    en.wikipedia.org/.../1951_USAF_resolution_test_chart

    A 1951 USAF resolution test chart is a microscopic optical resolution test device originally defined by the U.S. Air Force MIL-STD-150A standard of 1951. The design provides numerous small target shapes exhibiting a stepped assortment of precise spatial frequency specimens.

  3. High Frequency Global Communications System - Wikipedia

    en.wikipedia.org/wiki/High_Frequency_Global...

    The High Frequency Global Communications System (HFGCS) is a network of single sideband shortwave transmitters of the United States Air Force which is used to communicate with aircraft in flight, ground stations and some United States Navy surface assets.

  4. Airband - Wikipedia

    en.wikipedia.org/wiki/Airband

    Airband or aircraft band is the name for a group of frequencies in the VHF radio spectrum allocated to radio communication in civil aviation, sometimes also referred to as VHF, or phonetically as "Victor". Different sections of the band are used for radionavigational aids and air traffic control. [1] [2] [3]

  5. Have Quick - Wikipedia

    en.wikipedia.org/wiki/HAVE_QUICK

    Once the target frequencies were identified, radio frequency jamming could easily be employed to degrade or completely disable communications. The Have Quick program was a response to this problem. Engineers recognized that newer aircraft radios already included all-channel frequency synthesizers along with keyboards and displays for data entry.

  6. Aircraft emergency frequency - Wikipedia

    en.wikipedia.org/wiki/Aircraft_emergency_frequency

    The aircraft emergency frequency (also known in the USA as Guard) is a frequency used on the aircraft band reserved for emergency communications for aircraft in distress.The frequencies are 121.5 MHz for civilian, also known as International Air Distress (IAD), International Aeronautical Emergency Frequency, [1] or VHF Guard, [1] and 243.0 MHz—the second harmonic of VHF guard—for military ...

  7. Air Force Spectrum Management Office - Wikipedia

    en.wikipedia.org/wiki/Air_Force_Spectrum...

    Obtains certification and frequency licenses to operate satellites, land mobile radios, emergency radio systems (air-to-ground and air-to-air), radars, weapon guidance systems, and all capabilities that are spectrum-dependent. Provides functional management for the spectrum management career field. [1]

  8. Military Auxiliary Radio System - Wikipedia

    en.wikipedia.org/wiki/Military_Auxiliary_Radio...

    The military station operator will announce the specific amateur-band frequency being monitored. Usually, MARS stations are located in military and government installations such as The Pentagon, [5] Fort Huachuca, Andrews Air Force Base, Nellis Air Force Base, as well as Navy bases such as NAS Whidbey Island and several Coast Guard locations.

  9. Emergency Action Message - Wikipedia

    en.wikipedia.org/wiki/Emergency_Action_Message

    The messages are then relayed to aircraft that are on alert by the U.S. Strategic Command at Offutt Air Force Base in Omaha, Nebraska, via single-sideband modulation radio transmitters of the High Frequency Global Communications System (formerly known as the Global High Frequency System).