CosmoGirl-Sat CW beacon date format

A few days ago I was asking here if anyone knows the CW broadcast format of KOSEN-1 (See the post HERE)

I come again to ask if anyone knows the CW transmission format of CosmoGirl-Sat.

I looked on the internet but didn’t find anything concrete and I really wanted to understand what the satellite transmits. I contacted the team via the email provided in the IARU coordination, but there was no response until then :worried:

All help is welcome!!

73’s de PU4ELT :brazil:

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Hi Igor,

They put the CW beacon format on their website.

Contrary to this format, they apparently decided to put the satellite’s callsign (JS1YOI) in the position of the groundstation’s callsign and leave the position for the latter zeroed (000000) instead.

You may have noticed that one of the two CW beacon types is always 000000A800. It’s type 2 which has 3 of its 5 bytes for the gyros. However, CosmoGirl-Sat has no gyros, hence it starts by 000000.
The first 3 bytes of type 1 give information about the battery (mV, mA, °C). However there is no conversion formula published how to calculate the hex numbers into meaningful values (not only a Kosen-1 problem).
Since all three satellites are pretty similar, you may try to use SAKURA’s conversion formula.

I noticed, that while Sakura and Sagansat0 has telemetry for solar panels -x as well as for +y and -y, CosmoGirl-Sat’s telemetry table shows -x and +y as well as +x instead.

And I’m in contact with one of the team members who tries to get answers to the above mentioned things and if there will be also a GMSK beacon or not.

I’ve finished the decoder and the dashboard already on September 1st, but now waiting for the last answers.

You may send questions and your reception reports to contact2@cosmosgirlham.org.

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You have a great idea Daniel. Analyzing the first 3 bits of my reception HERE I did the calculations according to the conversion table provided by the SAKURA team and the data really doesn’t seem absurd at all.

I will send a message to the email you provided and hope for a response. Throughout this evening here in Brazil I must try to better understand the rest of the data sent by CosmoGirl-Sat at my reception mentioned above

A47FB81420

B8 = 184 in decimal

(I think B8 is the battery temperature value as mentioned in the table you shared)
Screenshot_4

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Ha, why do anyone come up with this kind of formula for such a simple thing as temperature ?! :smiley:
Like, what’s wrong with slope and offset ? sheesh.

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It’s a question I ask myself too hahahahha. I’m not an engineer or programmer, but I believe there is a more efficient way to send this data in CW

But there is an even bigger problem, which is not making this conversion table available to us :rofl:

The SAKURA team is truly to be congratulated for making the entire process available to build a decoder for the satellite :grin: :grin: