Looking for a "spare parts" quarantine antenna project

Hi all! New here. I became familiar with SatNOGS at Hamvention but sort of tucked it into the back of my mind as I didn’t have the time, space, 3D printer, etc to consider building a directional station. The TAPR conference video got me interested in playing around with the idea of a non-rotator station with stuff I had laying around.

For now I have an Arrow dual-band satellite yagi in my attic. It’s literally wire tied to a scrap piece of tubing and leaning against a post. I’ve removed some elements to make it less directional. It’s actually working quite a bit better than I would have expected, but as you can imagine some passes are better than others.

I have a ton of magnet wire scrap from a place the wife used to work, appears to be aluminum conductor roughly equivalent of 12 or 10 gauge wire. It bends and holds form quite well. I also have plenty of 50 ohm coax in various types and a bunch of RG-6 (75 ohm). I’ve been researching antennas to build to replace the Arrow, using materials on hand as I’m trying to avoid going out much.

It looks like a Moxon seems to be a good choice with the on-hand materials, no special impedance coax needed outside of what I already have, and seems more forgiving of less than perfect dimensions than other designs. I’d love to hear your thoughts on this, or other antenna projects I might be missing. I’ve looked into QFH, but there’s a lot of information out there and it seems like it would be more difficult to get right.

Hi
Been there done that. Thinking what antenna to build and it all started with wanting to get those weather-maps from the NOAA satellites. This also got me started with SDRs, needing the 40kHz bandwidth.

I have tried verticals, turnstyles, Lindenblad, dipoles, Slim Jims (J-pole like) Eggbeaters, Moxon and eventually built QFH antennas and I consider them to be the best Omnidirectional antenna for satellites. They are not that hard to build for VHF and UHF. Look at my stations 568 & 724.

I feed them with Satellite TV, low loss, 75Ohm coax because I consider low loss is more important than a slight mismatch in Z as I am not transmitting and have LNAs at the antennas

There is plenty information available like https://www.jcoppens.com/ant/qfh/calc.en.php
Pay attention on how to get Right hand circular polarization as this can be confusing when feeding the QFH from the top.

Have Fun, 73 Bob

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I live in Athens which is actually like a “forest” of TV reception antennas on rooftops. Many of them are just old and unused. In the past I have been scrapping such old TV antennas (especially VHF) to build cross dipoles. If you take care of the polarization and feeding, you can build yourself a quite decent antenna for reception.

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