On air this second on the NCDXF/IARU beacon network: 20m 4U1UN (United Nations, New York), 17m YV5B (Caracas, Venezuela), 15m OA4B (Lima, Peru), 12m LU4AA (Buenos Aires, Argentina), 10m CS3B (Santo da Serra, Madeira). 18 beacons, 3-minute cycle, 10 seconds each. Server snapshot, refreshed every 5 minutes. The tool below is live.
Updated
Who is transmitting right now on each band, where to point the beam from your locator, and which beacons you have actually heard. The 18 beacons rotate on a fixed 3-minute cycle, computed from UTC.
All 18 beacons
· cycle on the selected band, tap a row to highlight itHeard log: nothing yet| Call | Location | Grid | Heading | Distance | Next Tx | Heard |
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What it does
Shows which of the 18 NCDXF/IARU beacons is transmitting right now on 20, 17, 15, 12 and 10 metres, the next two in the cycle, and the beam heading and distance from your locator, with a compass on every band.
Data and refresh
The beacon schedule is fixed: 18 beacons, 10 seconds each, a 3-minute cycle synchronised to UTC. Nothing is fetched; the monitor computes the slot from the clock, so it works offline too.
How to read it
Tune to a band, wait for the beacon shown as on air, and listen for the callsign in CW followed by four dashes at 100, 10, 1 and 0.1 watts. Tick the ones you hear: the log stays in your browser.
Who it is for
Anyone checking a path or an antenna in a minute: if you copy the 100 mW dash from a beacon, that band is wide open in that direction.
What it cannot tell you
This page knows the schedule, not the propagation. It derives who is transmitting from the clock, so it will happily show you a beacon that is inaudible at your end, or one that is off the air for maintenance. Whether the path is open is your receiver’s job to answer, not this table’s. It also cannot tell you how well you are hearing: the beacon steps down through 100, 10, 1 and 0.1 watts precisely so that you can judge that yourself by counting the dashes you can still copy.
Using it in practice
Give one frequency a full three minute cycle rather than tuning around. Sit on 14.100, follow the highlighted row, and note which of the eighteen beacons you copy and how many dashes you get from each. Four dashes is a strong path, callsign only is a marginal one. Do that on two bands in the same quarter of an hour and you have a better picture of where the openings are than any prediction can give you, because you measured it from your own aerial with your own ears.
Frequently asked questions
How does this page know which beacon is transmitting without hearing it?
It is not listening to anything. The IBP schedule is fixed and locked to UTC, so the beacon on any of the five frequencies at any instant can be worked out from the clock alone. That has one consequence worth knowing: the display is only as accurate as your computer clock, so if yours has drifted by ten seconds, so has this page.
What is the Heading column measured from?
From your own locator, which you type into the box at the top or set with the locate button. It is the great circle bearing from you to that beacon, with the distance beside it, so you can turn a beam onto the path before the beacon comes round again.
What happens when I mark a beacon as Heard?
The count is kept in your own browser and nothing is sent anywhere. It is there so that over a few cycles you build a picture of which paths are genuinely open for you and your antenna, rather than which ones ought to be open. The Clear button empties the log.
Why does the highlighted row keep moving?
Each beacon transmits for ten seconds on a band before handing over to the next, so with eighteen beacons in the network the full cycle comes round every three minutes. The highlight follows that cycle live, and three minutes is also how long you wait for one particular beacon to return to one particular band.
What do the five tabs across the top do?
They switch the table between the five IBP frequencies: 14.100, 18.110, 21.150, 24.930 and 28.200 MHz. Every beacon appears on all five in turn, so listening for the same beacon on two tabs is a direct comparison of which band is open on that path.
Why can I hear a beacon on one band and not the one above it?
Because each band has its own maximum usable frequency, and the beacons are there to find it. If 20m brings in a beacon that 15m does not, the path is open but the ceiling is below 21 MHz. Work up the tabs until the signals stop: the last band that still copies is the highest one worth calling on for that direction.