noaa 19 direct sounder broadcast?

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weathersatelite
Posts: 7
Joined: Tue Jan 14, 2020 4:34 am

noaa 19 direct sounder broadcast?

Post by weathersatelite » Tue Feb 25, 2020 10:31 pm

what is it? all I know is from gpredict/look4sat(android). it broadcasts on 137.7700 MHz. mode BPSK.
what is that mode? and are there programs to decode it if it is something like a picture.

Aussie Susan
Posts: 41
Joined: Sun Jul 31, 2016 1:55 am

Re: noaa 19 direct sounder broadcast?

Post by Aussie Susan » Wed Feb 26, 2020 2:28 am

The NOAA satellites (and others) that work in the 137MHz range use APT (Automatic Picture Transmission).
I think you will find that the modulation is a bit more complex the BPSK (binary phase shift keying) but the first step to decoding is to use an FM receiver. That will produce an audible signal (basically a tone that clicks every second or so) that itself can them be decoded to the data stream.
Start with looking up APT and you should find lots of references.
Susan

weathersatelite
Posts: 7
Joined: Tue Jan 14, 2020 4:34 am

Re: noaa 19 direct sounder broadcast?

Post by weathersatelite » Wed Feb 26, 2020 5:20 pm

I have received apt and decoded it. was wondering what other thing is

Aussie Susan
Posts: 41
Joined: Sun Jul 31, 2016 1:55 am

Re: noaa 19 direct sounder broadcast?

Post by Aussie Susan » Thu Feb 27, 2020 2:07 am

Where did you get the information from?
Looking at http://mdkenny.customer.netspace.net.au ... .html#noaa, the only mention of BPSK is on the 'Command' section and in the 2GHz range.
There is a 137.77MHz mentioned in the TIP section that talks about '8320 BPS bi-phase-level/PM - TIP is 'TIROS-N Information Processor (https://www.ssec.wisc.edu/mcidas/doc/pr ... ts-10.html)
Susan

weathersatelite
Posts: 7
Joined: Tue Jan 14, 2020 4:34 am

Re: noaa 19 direct sounder broadcast?

Post by weathersatelite » Thu Feb 27, 2020 3:13 am

as mentioned it is in gpredict/ and look4sat an android sat tracker.
open gpredict. choose to view NOAA 19.
right-click sat info/noaa 19.
click transponders
3 item down.
in android app
chose view noaa 19
tap on it
you will see a sky map
below is info
3rd item down

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