Palomar Amateur Radio Club STEM Experimentation Lab PARC STEMLab

WSPR - Weak Signal Propagation Reporter

WSPR, Weak Signal Propagation Reporter, is a radio protocol that is used to probe potential propagation pathways using low-power transmissions that can be monitored at distant stations.

A well-developed reporting network then publishes these reception reports. It was originally developed by Joe Taylor, K1JT. WSPR uses a transmission mode called MEPT-JT (Manned Experimental Propagation Transmitter – Joe Taylor) and narrowband FM modulation. Stations will transmit the beacon with their callsign, location and transmit power for about two minutes.

There are usually multiple frequencies used by WSPR in each amateur band:

WSPR Frequencies
Band Receive Transmit
160 meter 1.836600 MHz 1.838000 – 1.838200 MHz
80 meter 3.586600 MHz 3.570000 – 3.570200 MHz
60 meter 5.287200 MHz 5.288600 – 5.288800 MHz
40 meter 7.038600 MHz 7.040000 – 7.040200 MHz
30 meter 10.138700 MHz 10.140100 – 10.140300 MHz
20 meter 14.095600 MHz 14.097000 – 14.097200 MHz
17 meter 18.104600 MHz 18.106000 – 18.106200 MHz
15 meter 21.094600 MHz 21.096000 – 21.096200 MHz
12 meter 24.924600 MHz 24.926000 – 24.926200 MHz
10 meter 28.124600 MHz 28.126000 – 28.126200 MHz
6 meter 50.293000 MHz 50.294400 – 50.294600 MHz
2 meter 144.488500 MHz 144.489900 – 144.490100 MHz

Anyone can participate with the correct (free) software. The PARC SDRs using OpenWebRX+ or the KiwiSDR can monitor various WSPR frequencies and can report receiving messages to the network.

WSPR can even be used for antenna testing by doing before and after comparison of received data. This is more of a long-term test regimen and requires accurate time synchronization.

References: