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:
Compatibility image link
Waterfall:
Compatibility image link
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):
Compatibility audio link
And the bonus, DSB images:
Compatibility image link
Channels 1-20 are left-to-right then bottom.
And also AVHRR scan motor current as of today:
Compatibility image link
Wow, nevedel som, že satelity ešte stále vysielajú analógovo. Miliarda ľudí si musela vymeniť televízny prijímač a tisíce meteorológov stále ladí SSTV…
A čo sú tie zubaté šikmé hrany v horných rohoch obrazu?
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!
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 HRPTJPEG 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.
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).
Does the embedded audio work for anyone? I think it’s not even an official Lemmy/Markdown feature.
It works in the default Lemmy web UI. I tried it with Opera (Android) and Firefox (Manjaro). It relies on the browser’s media player.
There’s still the link below it, for when it doesn’t work, which I expect from most Lemmy clients and probably Kbin too.
Oh, I didn’t check if the compatibility link is any different, I assumed it was the same.
Of course you cannot embed an external site in a comment but the raw file does seem to work, in browsers at least.
Another interesting thing I noticed about these broken APT images is the channel B sync marker is repeated twice instead of the channel A marker. This is why the sync fails, and it makes a “tick tick” sound instead of the “tick tock” sound it normally makes.
I’d love to know what is causing this, but I think only NOAA knows what is going on with that.
