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Comment by th0ma5 | Hacker News Reader

Sort of a goal of mine has been to bounce off the ISS APRS digipeter at least, but building a satellite aiming rotator setup has been my hangup, although in theory I could try handheld yagi? I would like to make a rotating setup though for general satellite work tho.

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Try it handheld first. It won't be perfect but you'll hear the APRS and get a feel for how (not) precise it has to be. You're going to need the antenna either way. It's impossible for me to convey how extremely janky my first DIY antenna was for this. It's not a super-precise operation: https://www.youtube.com/watch?v=2y6A6ur7yas&t=520s

I'd like to do the same thing. I have a goto mount telescope, and I've used this software: (https://heavenscape.com) to track the space station with the telescope. It's a little tricky, and you don't have too much time to realign the mount etc if something is wrong, given that the ISS passes usually only last a few minutes, but I did manage to get it to work after a couple of tries. If I had to do it again I'd practice with other random satellites first.

What I've been thinking about is coaxially mounting an antenna and using the telescope mount as an antenna mount. The only problem is that you do need a telescope on the mount to shoot some alignment stars, so you can't just mount the antenna, and I don't know how much the metal in the telescope would interfere with the antenna.

I've had good luck with a handheld D74A and a handheld arrow yagi. I don't make it in every time but I've hit it successfully a few times.

There's a low-cost tracking antenna mount that's quite popular for first attempts, known as "a friend".

You lash an inclinometer to the boom, and hand them a compass. Tell them where the pass begins, and hope they can acquire it visually after that.

The hardest part is doppler correction, really. Get the software for that squared away well in advance.

I have managed to do this without a directional antenna. I just kept trying. Using nothing more than a dual band vertical antenna in my attic with 50w power.

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