Live VLF Natural Radio

A collection of live natural radio streams of the VLF band.


The VLF signals are picked up by amateur receivers where they are timestamped by GPS and filtered to remove power-line interference. The cleaned signals are sent across the Internet to a central server.

The receivers use either Spectrum Lab on Windows or vlfrx-tools on Linux.


Incoming VLF streams from the receiver sites are processed and recorded. There the signals are automatically analysed to detect interesting natural radio events such as whistlers and aurora. The server re-broadcasts the signals over the Internet as live audio streams.

The server uses vlfrx-tools for signal processing and Icecast for re-broadcasting the streams. The server is located in Germany on a Hetzner Linux host.


Signals are stored on the server for about 20 days where they are available for free access for research or hobby interests such as amateur radio. There is also a large database (about 300Gbyte) of detected events going back several years which is available for research.


If you are running a reasonable quality GPS timed VLF receiver, continuously, and intend to do so for a long period of time, and if you have spare Internet bandwidth of about 80kbps, then you might like to contribute a signal to the network. High latitude locations are especially desirable, and locations outside Europe and North America.


The maintainers and other interested parties tend to congregate on the Yahoo! VLF_group. There you can get advice on how to set up your receiver and GPS timing system, and how to access and use the data.


The site owner Paul Nicholson can be reached at