Propagation Information

Propagation for Shortwave Radio (0 - 30 MHz)

Shortwave radio is radio transmission using shortwave radio frequencies. There is no official definition of the band, but the range always includes all of the high frequency band (HF), and generally extends from 1.7–30 MHz (176.3–10.0 m); from the high end of the medium frequency band (MF) just above the mediumwave AM broadcast band, to the end of the HF band.

Radio waves in the shortwave band can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere. Therefore, short waves directed at an angle into the sky can be reflected back to Earth at great distances, beyond the horizon. This is called skywave or "skip" propagation. Thus shortwave radio can be used for very long distance communication, in contrast to radio waves of higher frequency which travel in straight lines (line-of-sight propagation) and are limited by the visual horizon, about 40 miles (64 km). Shortwave radio is used for broadcasting of voice and music to shortwave listeners over very large areas; sometimes entire continents or beyond. It is also used for military over-the-horizon radar, diplomatic communication, and two-way international communication by amateur radio enthusiasts for hobby, educational and emergency purposes, as well as for long distance aviation and marine communications.

Realtime HF Propagation Tools and Solar Data


Realtime IONOGRAM FROM RÜGEN 54.6N 13.4E

WSPR (Weak Signal Propagation Reporter)

WSPRLite Kit from SOTA Beams. It is a self-contained propagation beacon transmitter. The WSPRlite is a special test transmitter that sends a signal to a Worldwide network of receiving stations. When used with our web-based DXplorer system, it's a powerful new way to evaluate antenna performance. Going way beyond antenna modelling or antenna analyzers, this unique system allows you to see how your antenna is performing in its actual location and in real-time!

Realtime WSPR DXplorer Map of HB9RYZ (20 Watt Transmitter) Firmware v1.07 - 20m from 5.- 15. June 2017

My Conclusion
After almost 2 weeks transmitting my WSPR signal with my small ATAS 100 Antenna and about 20 Watt on 20m, I was pleased to see my signal received in Europe, North America and South America. I was wondering, why my signal was not received in Africa, Middle East, APAC or Australia. It was possible to have Phone-QSOs in this time period with VK. So I guess, WSPR stations are just a few in these areas or the band condition on 20m was very poor at that time.

Received by: CX1EUY (7751km SNR -23), KL7L (7751km SNR -11), VY0ERC (Eureka Weather Station 4953km SNR -29), TI5LUA (9387km SNR -24), KP3FT (7432km SNR -21).

Finally, the WSPR Lit Kit from sotabeam is excellent. Easy to install and configure. It could be interesting to observe the band condition on a certain band over a long period from your home QTH and than compare with other Ham Radio propagation results. But this is not real time, this is the past, the history which does not count for me!
To be frankly, to know if your antenna has the right performance - it's just a guess (band conditions, availability of WSPR receivers, etc.) . It's easier to switch on your transceiver - check the DX-Cluster - and you will know right away how good your antenna will perform.

WSPR Informations
WSPRNet Weak Signal Propagation Reporter Network Portal. The WSPRNet is a group of amateur radio operators using K1JT's MEPT_JT digital mode to probe radio frequency propagation conditions using very low power (QRP/QRPp) transmissions. The software is open source, and the data collected are available to the public through this site.

WSPRLite Introduction and Presentation by Richard G3CWI [1'183 KB]

More information on the WSPRLite Facebook Group.