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No one else I knew was doing anything like that, but the closest was the Moonbounce radio group at Dapto.
The receiver isn't too hard to design, a SDR with an high gain pre amp will do, even a decent scanner with a pre amp will give results. Especially on sun noise.
That said, a dedicated design with a proper narrow band front end and low noise cascaded, double balanced mixer, would be needed. I do have a homemade double balanced mixer receiver, and I first thought it faulty when I made it as there was absolutely no noise from it when I switched it on. After some hours checking and rechecking, I decided to connect an aerial to it and see if a signal could force its way through. When my ears recovered from the cacophony of stations, I realized that I had been tricked by the very characteristic of a double balanced mixer, lack of conversion noise as its cancelled out in the miser stage. My receiver has no RF amp stage, so is a bit 'deaf' but works well enough and uses only 3 easy to get integrated circuits, no surface mounted bits and is built on a perfboard, not even a circuit board.
I may design a cascaded RF amp stage, along with an outboard attenuator and filter, and have another go, but with the coming world problems, astronomy, and radio in general, is on the back burner.
The intermediate stage would need some more rejection as two tuned circuits aren't enough and there is some 'double spotting' on strong signals.
I seem to remember that a frequency of around 20 megahertz was optimin, and also for Jupiter around 22 megs was a good place to start. The signals sound like an electrical storm on earth, with frequent crashes and bangs. It is a rather wide band, for space exploration, signal, but much narrower than a normal broadcast station, and more difficulty is added because the signal drifts around quite a bit, so some form of adjustable oscillator, tuned by the signal strength may be needed, its possible a phase locked loop would do it, with the phase being fed back into the oscillator from the biggest noise level.
Then there is the matter of an aerial, 'cause at 20 megs, 1/2 wavelength is 10 meters, so a tuned dipole would be 20 meters long and need to be steerable, unless a fixed aerial was used and the timing of the planets rise above the horizon calculated for the location etc.
Thanks for replying, at least someone is watching !!
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