NCDXF/IARU beacons on 14100 kHz: eighteen stations in three minutes

What you hear

On 14100 kHz in CW there is a callsign in fast Morse, about 22 words per minute, and then four dashes of one second each, every dash ten times weaker than the one before: 100 watts, 10 watts, 1 watt, a tenth of a watt. Ten seconds later another callsign from another continent does the same. In three minutes the whole chain has run through and it starts again from the top: 4U1UN at the United Nations in New York, VE8AT in the Canadian Arctic, W6WX in California, KH6RS in Hawaii, ZL6B in New Zealand, VK6RBP in Western Australia, JA2IGY in Japan, RR9O in Novosibirsk, VR2B in Hong Kong, 4S7B in Sri Lanka, ZS6DN in South Africa, 5Z4B in Kenya, 4X6TU in Israel, OH2B in Finland, CS3B on Madeira, LU4AA in Argentina, OA4B in Peru and YV5B in Venezuela.

The dashes are the point. If all four come through, the path is excellent and a few watts would do for a contact; if only the first one is audible, the band is barely open in that direction. The timing is held by GPS, so if you know the UTC time you know who is on without reading any Morse: 4U1UN starts at the top of every third minute on 14100, VE8AT ten seconds later, and so on down the list.

Who transmits and why

The system is run by the Northern California DX Foundation together with the IARU, the international union of amateur radio societies. It began in 1979 with a single beacon in California and grew into the present layout of eighteen stations on five bands in the 1990s. Each site is hosted by a local club or institution and runs the same kit: a 100 watt transmitter, a GPS receiver for timing and a vertical antenna that radiates equally in all directions, so that what you hear reflects the ionosphere and not the antenna. The purpose is a free, continuous sounding of the shortwave bands for anyone with a receiver, and automated monitoring networks use the same beacons to map propagation hour by hour.

Not all eighteen are on the air at any given time. Equipment breaks, sites lose power, and a beacon can be silent for months; the foundation's website shows which ones are running.

When and where to listen

20 m is open to somewhere at almost any hour, which makes 14100 the band to start with. From a European receiver the morning brings the east: JA2IGY, VR2B, RR9O, 4S7B and 4X6TU, with OH2B and CS3B audible nearly always because they are close. The afternoon and evening bring the west: 4U1UN, W6WX, LU4AA, YV5B, with ZS6DN and 5Z4B from the south. Around the equinoxes the band stays open late and the long paths to ZL6B and VK6RBP appear at dawn and dusk. A receiver in North America hears the opposite pattern, with Asia and the Pacific in its evening.

The beacons sit on exactly 14100.0 kHz, so with a narrow CW filter they all land on the same note and only the rhythm and the strength change from one to the next. The same chain runs on 18110, 21150, 24930 and 28200 kHz, each band ten seconds behind the previous one, and the catalogue has them all.

In ShackDeck

Station catalogue → Beacons → NCDXF beacons 20 m. The program picks a public receiver that covers 14100 kHz, tunes it in CW and shows the waterfall, where each beacon appears as a short burst of Morse followed by four steps that shrink and vanish. No receiver, antenna or account of your own is needed.