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1919 Pop. Sci. Monthly Oct. 49/2 What is a radio beacon?

1922 Nature 20 May 650/1 Until two or three years ago the radiophares—or radio-beacons as they are called in America—were purely stations for giving ships their positions.

1929 Techn. News Bull., Bureau of Standards Nov. 108 The Bureau has found it necessary to give..attention to marker beacons, for two purposes. One is the adaptation of the marker beacon principle for use..on the airways in connection with the visual beacon system. Another is the provision of marker beacons as auxiliaries..with fog-landing equipment.

1932 F. E. Terman Radio Engin. xvi. 593 The instant when the received beacon signal goes through zero.

1937 Jrnl. Royal Aeronaut. Soc. 41 591 An analysis of the flight of an aeroplane, when directed by means of a radio beacon.

1962 Times 21 Feb. 10/2 Direct communication with the capsule was briefly lost as it reentered the atmosphere because of an ionization process, but beacon signals were received.

1929 Techn. News Bull., Bureau of Standards Nov. 108 The Bureau has found it necessary to give..attention to marker beacons.

1934 Jrnl. Royal Aeronaut. Soc. 38 828 When a pilot had to maintain height, to observe instruments to ensure that he did not get into difficulties, and had also to listen for the marker beacon.

1971 Gloss. Electrotechnical, Power Terms (B.S.I.) iii. vi. 24 Marker beacon, in aviation, radio beacon which radiates a signal to define an area above the beacon.