HB9AW Bakenmonitor 60 m

The HB9AW beacon in Sursee (Switzerland) transmits on 5291 kHz every five minutes: its call sign in CW, then five two-second dashes at 10 W, 5 W, 1 W, 100 mW and 10 mW. A network of receiving stations across Switzerland and beyond measures how strongly the beacon arrives at each location — the data the Radio Club Sursee publishes hourly.

This app shows those measurements.

STATIONS
All receivers with their current signal-to-noise ratio, calculated from the reported signal and noise levels, the distance from your own locator and the age of the last report. Sort by distance, SNR, name or last report, ascending or descending — the app remembers your choice. Stations that have stopped reporting are marked as silent rather than shown with stale values.

STATION DETAIL
The last 36 hours as three curves (signal, noise floor, SNR), an hour grid of the month — days by hours, coloured by SNR — that shows when the band is open at that location, the mean per hour and how reliably the station reports.

MAP
Your own outline map (no map service, no tracking), the transmitter, rings at 100, 200 and 400 km, every station coloured by SNR, and a time slider over the last 36 hours: watch the night move across the map. An optional trend layer estimates the coverage between stations and is labelled as an estimate, not a measurement.

PINNED STATIONS
If you operate a receiver, pin it. The app then checks once an hour in the background whether it still reports and whether its noise floor has risen, and notifies you when something changes. Without pinned stations there is no background activity at all.

YOUR LOCATION
Enter your Maidenhead locator (six characters, e.g. JN47BE). It stays on the device and is used only for distances. The app does not access GPS.

DATA AND CONNECTION
The app loads public measurement files from the beacon project's server and keeps them on the device, so it works offline with the last known data. It sends nothing but the request for those files. Server data is updated hourly; the app shows the server time stamp rather than pretending to be live.

Measurement data: Radio Club Sursee HB9AW. This app is an independent viewer for that data.