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1

Save time and aggravation. Get a Mobilinkd TNC-3 with cables and a ferrite bead for less than $200. The AFSK cables don't work well with VOX since (at least my cheap UV-5R) adds a hang of a few seconds after the tx ends. Not so with the Mobilinkd. UV-5R works pretty flawlessly with the TNC-3 and APRSdroid as well as MixW on my laptop. It is well worth the ...


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I've received the ISS during a school contact as described in the linked article on my UV5R using its supplied helical antenna. Copy was good from a high pass but held up for a long time. A beam should give better results for a low elevation pass. The ground station was 150 miles away so I couldn't hear that, of course. I've not tried sending to the ISS e.g. ...


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Some friends of mine and I launched a balloon a couple of years ago. We used an antenna based on the design shown here: http://www.trackuino.org/2010/04/trash-digging-at-its-finest-111-swr-vhf.html Unfortunately, the links are rotting. That page still exists, but the linked photos don't, nor the original reference they used. But the latter was captured by ...


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A quarter length antenna needs a ground plane, correct. Or at least large conducting plane. The radiation pattern of dipole antenna is just the double (like mirrored) as a quarter length antenna. The RC planes usually have two dipole antennas, that are positioned 90 degrees with respect to each other, so it can cover almost any angle. But for a baloon, ...


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You definitely can, but would benefit a lot from a dual band directional antenna. There are plenty of examples of self-built yagi antennas that are perfect for satellite work (such as https://hackaday.io/project/25143-wa5vjb-ultra-portable-dual-vhfuhf-yagi but there are lots of others in varying degree of sophistication and effectiveness). I particularly ...


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In theory, yes. In practice, "probably not". In my experience, the front end on Baofengs is not very good. We have a UV-82, and it just did not work when we tried to use it for amateur satellites (AO-91, AO-92, etc). When we replaced it with a Yaesu FT-60R we were finally able to receive the "birds". So while theoretically you should be able to receive LEO ...


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Radio waves will travel for billions and billions of miles through space if they're not interfered by matter. Consider the New Horizons Interplanetary Space Probe that did a fly-by of Pluto in 2015. I am not sure how far that was but Pluto is about 2.6 Billion miles from Earth at its closest. The transmitters have a power of 12 watts! One of the antennas ...


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You don't need to imagine it, because it's true. Many amateur satellites have around half a watt of output, and they're easily received on the ground with only a modest antenna (a 3-element yagi helps, but I've worked AO-91 and AO-92 with quarter-wave verticals). 8 watts is far more than enough. It doesn't take that much power to get above the noise floor ...


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