Back in December, I carried out an experiment to find and record the peak of the Geminids meteor shower by listening to the GB3MBA 50 MHz beacon which is 500kms from my location. See post HERE
On the afternoon of 4th of January 2024, there was the peak of the Quadrantids meteor shower which tends to be very narrow but intense. This time, I just took some screenshots of the meteor reflections.
Introduction... Back in 2022, a new radio beacon called GB3MBA was put on air on the 50 MHz band and its primary purpose was carrying out meteor scatter experiments. Located near the town of Mansfield in the centre of England, the beacon runs 75-watts into a small Moxon antenna which beams straight up.
Unlike most amateur radio beacons, this one is basically a carrier that is on nearly all of the time which is exactly what is needed for meteor scatter experiments. The main coverage area is the UK itself but as I'm 502 kms from the beacon, I'm close enough for it to be of use.
For the Quadrantids meteor shower, I was using a Yaesu FT817 on USB as a receiver and the antenna was a 2-element Yagi in the attic of my house. The antenna was beaming about 120 degrees which is about 45 degrees off the beam heading for the beacon (The choice of beam heading is determined by the space in the attic and I wasn't trying to beam away from the beacon).
Quadrantids screen shots...
The image above shows the composite collection of seven different screenshots. As can be seen, there was plenty of evidence of pings and bursts from the GB3MBA beacon.
The images on the blog are quite small and a link to a larger version of the image is on Facebook HERE.
I'll use the more detailed example above to explain what you are looking at. The time is moving from right to left and you will notice the 30-second timestamps. As my receiver isn't GPS locked, I'm probably around 5 Hz off frequency which is ok.
If I was hearing the beacon directly, it would show up as a solid yellow line going across the centre of the screen. Instead, you are looking at the signal reflecting / refracting off the trail of electrons left behind by the meteor as it burnt up. As these electrons are in motion in different layers of the upper atmosphere, there is some doppler shift on the signal.
In the example above, the 50 MHz signal lasted for about 90-seconds.
The signal on the far right of the image above is one of my favourites. This is called an 'epsilon' echo as it twirls around. What causes such a complex pattern as opposed to the other 'smudges'?
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