Monthly Archives: May 2017

Contest + Meteors + SDR = Fun!

The first weekend of May each year hosts a Europe-wide VHF/UHF contest. It’s one I always look forward to: there’s a decent chance of tropo on some of my favourite bands (unfortunately not this year); a slim chance of Es (definitely not this year!); and, most reliably, it’s around the peak of the Eta Aquariids meteor shower.

Eta Aquariids meteors are quite unusual because they are relatively swift (at 66.9km/s) compared with many other shower meteors. When seen visually, they leave long and persistent trains in the night sky. In a similar fashion, from a radio perspective they often result in long and intensely strong “bursts”. Combined with a decent peak hourly rate of 40 and a lot of QRO, well-sited stations all over Europe, this can make for some interesting listening! This year did not disappoint with many bursts heard on 144MHz, some lasting tens of seconds.

A step up from simply tuning around searching for meteor-scatter bursts is to use a Software Defined Radio (SDR), with appropriate software, to record a portion of spectrum to hard disk for a period of time. This data can then be viewed after the event, tuning across the recorded spectrum as if it was in real-time. As an example, I used Simon Brown’s excellent SDR-Radio suite (Version 2.3 in my case) to do just that at various points through the weekend, capturing several very good meteor bursts.

Included below is a video of me using SDR-Radio’s data file analyser to play back signals captured during one good burst on 144 MHz, which I’ve annotated with information about each station received, wherever possible.  Enjoy!

This data was captured in IO51vw using an 11el F9FT antenna at 6m a.g.l., azimuth 095 degrees, a mast-head preamp into an active 0dB loss splitter, feeding an RTL SDR dongle on one port. The recorded spectrum was originally 1MHz wide, centred at 144.280MHz, but I’ve used the data file analyser to zoom in such that the spectrum now covers from approximately 144.150 MHz to 144.410 MHz.