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. The signals are automatically analysed to detect natural radio events such as whistlers, aurora, and triggered emissions. 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. Two computers are used to share the load. They are located in Germany on Hetzner Linux hosts.


The maintainers and other interested parties tend to congregate on the Yahoo! VLF_group. The site owner Paul Nicholson can be reached at