Radio propagation beacon

An amateur radio propagation beacon is a radio beacon, whose purpose is the investigation of the propagation of radio signals. Most radio propagation beacons use amateur radio frequencies. They can be found on LF, MF, HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.

The International Amateur Radio Union (IARU) and its member societies coordinate beacons established by radio amateurs.

Most beacons operate in continuous wave (A1A) and transmit their identification (call sign and location). Some of them send long dashes to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like radioteletype (F1B) and PSK31 (G1B).

Amateur experiments in the 2200-meter band (135.7-137.8 kHz) often involve operating temporary beacons.

In the United States and Canada, unlicensed experimenters called Lowfers establish low power beacons on radio frequencies between 160 kHz and 190 kHz.

The International Amateur Radio Union Region 2 (North and South America) bandplan for 160 meters reserves the range 1999 kHz to 2000 kHz for propagation beacons.

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