The NCDXF International Beacon Project

The location of the international beacons (Image: NCDXF)

The location of the international beacons (Image: NCDXF)

How can you work out what parts of the world an HF band is open to and in only three minutes?

The answer is to listen to the International Beacon Project beacons, run by the Northern California DX Foundation (NCDXF).

The NCDXF, in cooperation with the International Amateur Radio Union (IARU), constructed and operates a worldwide network of high-frequency radio beacons on 14.100, 18.110, 21.150, 24.930, and 28.200 MHz.

The beacons are in USA (New York, California and Hawaii), Canada, New Zealand, Australia, Japan, Russia, Hong Kong, Sri Lanka, South Africa, Kenya, Israel, Finland, Madeira, Argentina, Peru and Venezuela, although some may be off the air at time due to maintenance/failure – you can find out the current state of play of all the beacons at any time by going to

Each beacon transmits in turn – a 10-second sequence every three minutes. Once they have sent their sequence on, say, 14 MHz, the beacon moves up to 18 MHz and repeats it and another beacon takes up their slot on 14 MHz.

These beacons help you assess the current condition of the ionosphere.

All you have to do is just listen on the beacon frequencies and copy the CW callsigns of the various beacons to figure out where the band is open to.

Working on the beacon at 4X6TU

Working on the beacon at 4X6TU (Image: NCDXF)

Because the beacons transmit at known times, it is easy to know which beacon is transmitting without actually knowing Morse code.

To know which beacon is transmitting see the schedule or use a computer program like BeSpeak by G0TLK or VOAProp by Julian G4ILO.

The beacons starts to transmit at 100W, before stepping down to 10W, 1W and 100mW in one-second steps. You may be surprised but it is very easy to hear some of the beacons transmitting at 100mW – which is 1,000th the full power of 100 Watts!

So how can you help the beacon project? Just make sure that you don’t transmit on or near any of the beacon frequencies listed – please check the bandplan

You can find out more about the beacons, including how to conduct unattended propagation research using a program called Faros, at

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