this post was submitted on 30 Aug 2023
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Amateur Satellites

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Discussion about amateur reception and processing of data from artificial satellites, primarily through radio signals but data from internet resources is welcome too.

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The main image in post was decoded with WXtoIMG as both noaa-apt and SatDump fail to synchronize it correctly.

Unprocessed image from noaa-apt:

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Waterfall:

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There you can see some breaks, the noticeable horizontal lines.

Which sounds like so (note: the waterfall shown above isn't from the same time as audio):

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And the bonus, DSB images:

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Channels 1-20 are left-to-right then bottom.

And also AVHRR scan motor current as of today:

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[–] [email protected] 2 points 1 year ago* (last edited 1 year ago) (2 children)

To je mi jasné, digitální vysílání bude několikanásobně efektivnější. Ale tyhle věci slyším poprvé: ten skener je pohyblivý optický senzor? Ty data o motoru jsi získal jak? Satelit je vysílá jako digitální hodnoty ve stejném pásmu?

Edit: Holy shit, NOAA-15 je jen 25 let starý. Tou dobou už přece existoval JPEG!

[–] [email protected] 1 points 1 year ago

Telemetria pochádza s tadiaľto: https://www.star.nesdis.noaa.gov/icvs/status_N15_AVHRR.php
Myslím že je to vysielané v DSB downlinku v rovnakom pásme.

JPEG mohol existovať, ale musela by sa vymeniť existujúca technika. Tieto satelity vysielajú aj HRPT, digitálne vysielanie v pásme L so 4x vyšším rozlíšením než APT v 5 kanáloch namiesto dvoch.
Info o príjme HRPT

JPEG kompresiu v pásme 137MHz využíva LRPT. LRPT aktuálne vysiela len Meteor-M No. 2-3 ktorý má bohužiaľ poškodenú anténu, takže signál je dosť kolísavý.

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago)

By the way, do you see my other reply under this (your) comment? I correctly set the comment language to Slovak, so it's possible it got filtered out if you don't have it in the Lemmy language settings.

It's not even a good comment though (mine).