New Satellites Suggestions for db: MemSat and EnduroSat

Yes, I saw that Tweet as well, so maybe the scheduling of their downlink transmissions is changing, maybe based on battery levels or other considerations.

I should have a chance to listen myself tonight, so I’ll see if any are transmitting. In the meantime, I guess we’ll keep the observations going, and see if they resume.

73,
Alan

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@fredy you were right that the ISS TLEs are still valid - I copied EQUiSat right on schedule tonight, but nothing from the other 2!

There might be a signal here, too (recorded at the same time as my personal one) but it is hard to tell:

 https://network.satnogs.org/observations/183660/

I guess we’ll see with more observations.

I vetted 183660 as good, there is a signal for sure :slight_smile:

For the rest let’s keep scheduling. :slight_smile:

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I see that 9 new TLE have been published, but not identified:

 https://celestrak.com/NORAD/elements/tle-new.txt

I guess we have to wait for someone (the CubeSat builder?) to do Doppler analysis to figure out which one is associated with each CubeSat.

Hopefully this will happen soon, as the most recent observation of EQUiSat shows that the current TLE being used (which show as “Using TLE 999 issued 4 days, 3 hours ago” ) aren’t very accurate anymore:

https://network.satnogs.org/observations/184444/

73,
Alan

I can use the new TLEs with my SDR on my laptop to see which one comes out correct.

From a 24h scan of the 70cm band (434 to 438MHz), only EQUISat at 435.550MHz is heard.

FSK signals were seen in the waterfall of 5 passes. A comparison of the Doppler curves against the recent TLEs shows that EQUISat is object 43551/98067NZ.

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I have updated EQUISAT TLE to object 43551/98067NZ one and for the rest to 43552/98067PA

EDIT: already scheduled observation will use the old TLE… I’ll try to update them later to the latest TLE.

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Nice work @cgbsat! ENDUROSat is only occasionally transmitting, and even then only one pulse per pass. See https://network.satnogs.org/observations/184278/ as our most recent successful observation of ENDUROSat. I don’t think anyone has received anything from MemSat yet.

Should we let the EQUiSat folks know about this analysis?

I have scheduled a number of new observations for EQUiSat starting at 17:54 UTC, so they should test out the new TLE, thanks @fredy!

I’m starting to understand the whole process now - very educational for me.

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Greetings from EnduroSat team. Thanks for the efforts.

The CW beacon (Morse Code + Melodie) is every 10min, when the battery level is above 80%.
There is also AX.25 beacon every 30 seconds

At that moment we received only AX.25 packets.

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The new TLE for EQUiSat looks perfect based on:

 https://network.satnogs.org/observations/184919/

:+1:

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One hint: If you would just use the link, it would be much easier to follow them:

https://network.satnogs.org/observations/184919/

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Hi @cgbsat, @fredy and KU2Y, thanks for your help on finding EQUiSat! We had been thinking it was 43550/98067NY but looking at your observations it seems like 43551 is spot on. We’re about to test decoding EQUiSat using those TLE. Our stations don’t give waterfalls so we’re really grateful for SatNOGS!

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hmm… I wonder why we haven’t been able to decode any of EQUiSat… @BSE is there anything special about the encoding? We have it as 9600 baud FSK. (sounds like there are beeps before the bursts though, maybe that is tripping up our decoder)

Hi @cshields, it’s 9600 baud 4FSK but unfortunately uses special encoding developed by Pacific Crest. We’ve only been able to decode transmissions with the same radio we used on EQUiSat, an XDL Micro.

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Do you know which of the protocols you selected?
From the user guide I see that the XDL Micro has the following ones that it can use.

^ From https://drive.google.com/file/d/0B1or6_Res46OMDA2VE42Ymx1Wlk/view Under the EQUiSat Resources page/

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Welcome to SatNOGS @LZ1IGI !

We finally got an observation that has both the CW beacon twice and the AX.25 beacon twice. The TLE used (for 43550) is pretty close, but does not seem to be an exact fit.

https://network.satnogs.org/observations/186457/

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Nice!

I’ve updated TLE for Endurosat to object’s 43552. Let’s see in the next observation if that fits better :slight_smile:

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You made great job . Your eco system is really incredible. I’m looking forward to contribute to it. I’m expecting more nice surprises from EnduroSat ONE in next days.

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Hi @cshields and @KD9KCK, regarding EQUiSat’s decoding we use “Transparent EOT.” We were hoping that would be decodable by conventional 4FSK decoders but we haven’t gotten any to work. Someone contacted us interested in trying to write a decoder in GNU radio, but he is currently on vacation. He got pretty far initially, and said that he determined the FSK offsets to be -2400Hz, -800Hz, 800Hz and 2400Hz. He was also able to identify periodicity in the data he was getting (we were sending “EQUiSat” over and over). Though Pacific Crest has also told us that the data is not fully “transparent;” there are some headers and checksums and other overhead in a transmission.

I personally plan on working on this starting in August (this is Mckenna, the tech lead of BSE), as I’ve always hoped for EQUiSat’s transmissions to be decodable by the HAM radio community in software!

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I might try my hand at manual decoding it. As 4FSK can spit out symbols then you need to figure out the framing. (I think)