Soyuz 2-1b Fregat-M 2020-09-28

@fredy FYI: NORAD just published the TLE data from this launch.

Cool I’ll take a look, just have in mind that the published objects could describe more than one satellite currently.

From spacetrack objects:

  • SALSAT: one of OBJECT D-M (46489-46497), selected OBJECT K (46495) to follow in DB
  • DEKART: one of OBJECT D-K (46489-46495), selected OBJECT H (46493) to follow in DB
  • MEZNSAT: one of OBJECT D-F (46489-46491), selected OBJECT D (46489) to follow in DB
  • NETSAT 1-4: one of OBJECT M-P (46497-46499), selected OBJECT P (46499) to follow in DB

Without received any signal:

  • YARILO-1: selected OBJECT L (46496) to follow in DB
  • YARILO-2: selected OBJECT L (46496) to follow in DB
  • NORBI: selected OBJECT J (46494) to follow in DB
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@fredy You seem to be right. Our guesses were 46495 vs. 46496 but taking the shifts it seems to be 46495.

This also fits the small sat separation sequence taking the direction vectors into account.

For YARILO-2 OBJECT F (46491) is suitable now, but the signal is very weak.

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An update on TLE sets (letters on OBJECTS names doesn’t follow the first line letters on spacetrack, I’m going to use letters from line 1(tle1) and not from the names (tle0)):

  • SALSAT : one of OBJECT J-K (46494-46495), selected OBJECT K (46495) to follow in DB (7 objects rejected)
  • DEKART : one of OBJECT E-J (46489-46495), selected OBJECT H (46493) to follow in DB
    (2 objects rejected)
  • MEZNSAT : one of OBJECT D-F (46489-46491), selected OBJECT D (46489) to follow in DB (nothing changed)
  • NETSAT 1-4 : one of OBJECT S-X (46502-46507), selected OBJECT U (46504) to follow in DB (changed a lot, still we can not separate each NETSAT, however we receive them all)
  • YARILO-2 : one of OBJECT E-G (46490-46492), selected OBJECT F (46491) to follow in DB (received, so found possible TLE sets, confirming @EU1SAT observation)

Without received any signal:

  • YARILO-1 : selected OBJECT H (46493) to follow in DB (changed to be closer to YARILLO-2)
  • NORBI : selected OBJECT J (46494) to follow in DB (nothing changed)

@R4UAB is it possible to get in contact with the teams of DECART or NORBI?

We have the DB pages that we would like to make better (pictures, descriptions, operators, transmission details, decoding schemes!)

e.g. https://db.satnogs.org/satellite/99783

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Here there is a description of decoding schema of MEZNSAT’s beacon.

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I’ve just seen @EU1SAT’s tweet and I checked NORBI’s observations and can confirm that NORBI transmits a faint signal every 2min.

Interestingly it seems that the random assignment of OBJECT J (46494) seems to be the one that currently fits better the faint signal. Another candidate is OBJECT K (46495) but given that it fits better to SALSAT I doubt it is NORBI. Will keep tracking it and see.

Apparently NORBI is using standard 9k6 FSK G3RUH AX.25 packet radio. See this tweet by EU1SAT.

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NORBI decoded for me also as 9k6 FSK using both UZ7HO-HS & Direwolf:

I was antenna tracking Object-J (#46494) and that produced several visible packets + one strong enough to decode. However, I did not attempt to measure the doppler accuracy of whether this is in fact the correct object for NORBI.

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Changed YARILO-1 to follow OBJECT E (46490).

Source PA0DLO tweet:

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Has anyone been able to decode YARILO-A/B or knows what mode they transmit?

Some information can be gleaned from the developer’s website. The presentation video “Onboard UHF transceiver” mentions module RFM69HW ( FSK 9600) and Reed-Solomon codes (each frame 64 bytes, the decoder can correct up to 8 bit errors), probably RS(64,48)?

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I’ve change to FSK 9600, the yarilo transmitters based on your post, however I have some doubts.

Disclaimer, my russian language skill are close to 0 :slight_smile: maybe @R4UAB could help on this.
In the video you linked (at 01:48) there is slide with two transceivers:

The first one, in the page described that downlink can be BPSK or GMSK and uplink FSK. The second one, again talks about GMSK and nothing for FSK. So, my guess, if any of these two was used then probably wasn’t customized to transmit FSK on downlink.

Also about the RFM69HW, in https://www.hoperf.com/%20modules/rf_transceiver/RFM69HW.html, it says that supports “FSK, GFSK, MSK, GMSK and OOK modulations”, so it doesn’t limit modulation to only FSK.

However in the video at 01:32, it says “модуляция: FSK”, but I’m not sure if it refers to uplink, downlink or both.

EDIT: I’m not very familiar with transceivers, so I may miss something

Have YARILO-A/B been seen since the post by PA0DLO? I tracked objects E/F on a high 1800utc pass today (2-Oct) along the U.S. East Coast w/ nothing heard around 435.350

Haven’t vetted the latest observations, but earlier today YARILO-2 was transmitting (faint signal). Check https://network.satnogs.org/observations/2916115/ waterfall at ~450s (the 3 dots). About YARILO-1 I’m still not sure if it transmits.

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The above transceivers are mentioned in the presentation as possible alternatives that have been rejected due to their large size, insufficient RF power, low data rate (maximum 38400 bps required) and high cost.

At the bottom of the webpage, in the “Radio communication system” section, it is stated: “The data transfer rate to the Ground Control Center is not less than 9600 bps; the speed can be increased to 38400 bps. The data exchange rate between nanosatellites is not less than 1200 bps.”

In the video at 04:59 “Radio link budget” on the left side there is a table for GCC -> Yarilo (downlink), it says “скорость передачи данных: 9600 бит/с”, on the right side there is a table for Yarilo -> GCC (uplink), it says “скорость передачи данных: 2400 бит/с”.

The data rate on the uplink is 2400bps, but it is noted that it is associated with the radio link budget (power 13dBW: 20W, feeder length 30m - losses 5.33dB). It is indicated that if it is possible to achieve an improvement in the radio link budget, it is possible that the data transfer rate will be increased.

I have not found in open sources information about the other modulation used for that project.

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The LoRa transmitter on NORBI is alive & well! Decoding it is another matter - will work on that…

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