Gravity-1 (Orienspace) 2025-10-11 ~02:15UTC

Information has emerged that CAS-11 satellite is scheduled to launch on a Gravity 1 rocket at around 2025-10-11 ~02:15 UTC.

A surprise for me (See IARU coordination HERE). There we have the frequency information…

Unfortunately, I’m working at the moment so I can’t do much research right now and calculate a preliminary TLE.

Edit : :double_exclamation_mark:Apparently we had a false positive about CAS-11 on board

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Anyone who would like to read through all the frequencies and modes on CAS-11 might want to have a drink & snack nearby… it’s a long list!

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I’ve created the entry in DB SatNOGS DB - CAS-11 and I’m adding (slowly :P) the transmitters.

Unfortunately not much information about the orbit, so difficult to calculate TLE to follow it.

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I’ve just discovered in the CAS-11 IARU coordination this “536 km polar orbit”. However a lot of times there are info about orbits and launches in IARU entries which are changed when the launch time comes. Not sure if we should trust it. :confused:

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12 transmitters added in the DB entry, any verification that I’ve added them right is more than welcome. For easier checking here is the entry in IARU splitted in paragraphs and organize transponders in frequency assignment:

Headline Details: A 6U CubeSat. Payloads include
HF/UHF - H/U Mode Linear Transponder
VHF/UHF - V/U Mode Linear Transponder
VHF/UHF - V/U Mode FM Transponder
VHF/UHF - V/U Mode digital store-and-forward Transponder
UHF - CW Telemetry Beacon
UHF telemetry beacon using AX.25 4.8k/9.6kbps GMSK.

The CAS-11 satellite will be equipped with a 2.45GHz multi-mode amateur radio satellite beacon transmitter, which is designed and built by university students, high school students and primary school students from Beijing Donggaodi Science and Technology Museum and Beijing University of Posts and Telecommunications under the guidance of CAMSAT, aiming to cultivate students’ knowledge, skills and interests in amateur radio satellites.

All transmission modes operate at 2.4 GHz, and the working modes are converted by the on-board computer program and ground remote control commands. It can work in the following modes:
CW Telemetry Beacon
FT8 Telemetry Beacon
PPM Telemetry Beacon
USB/SSTV Robot36
USB/SSTV PD120

  1. CAS-11 carries three VHF uplink and UHF downlink transponders, including a linear transponder with a bandwidth of 30kHz, an FM transponder and a digital store-and-forward transponder.

  2. CAS-11 carries a linear transponder with a bandwidth of 15kHz for HF uplink and UHF downlink.

  3. CAS-11 carries a basic CW beacon, which operates in the 70cm band and uses Morse code to send satellite telemetry data, which is a popular feature in the amateur radio community. The above transponders and beacon will work 24/7 when the satellite power supply is sufficient. Amateur radio enthusiasts around the world can use it for two-way radio relay communication, data storage and forwarding communication, and receive satellite CW beacons.

  4. CAS-11 carries three cameras, and the photos it takes are stored in the flash memory on the satellite. We have designed a simple remote control system based on DTMF commands. Amateur radio enthusiasts around the world can send DTMF commands to download the photo catalog and all photos taken by all cameras.

  5. CAS-11 carries an experimental payload, which is a multi-mode amateur radio beacon transmitter. This device is designed and produced by university students, high school students and elementary school students from Beijing Donggaodi Youth Science and Technology Museum and Beijing University of Posts and Telecommunications under the guidance of CAMSAT. This is an unprecedented satellite project in China. It has brought opportunities for learning and practicing amateur radio and amateur satellites to students of all grades from elementary school to university, and promoted the application of amateur radio in space.
    This 2.45GHz experimental beacon transmitter can switch to transmit 5 different modes of radio signals, and it will work continuously when the satellite is fully powered.

Proposing the following bandwidths and data rates:
V/U Mode Linear Transponder: 30kHz bandwidth
V/U Mode FM Transponder: 16kHz bandwidth
V/U Mode Digital Transponder AX.25 GMSK Downlink:4.8kbps
H/U Mode Linear Transponder:15kHz bandwidth
70cm CW Telemetry Beacon:22wpm
70cm AX.25 4.8k/9.6kbps GMSK Telemetry: 4.8k/9.6kbps
13cm Multi-mode Beacon with:

  • CW Telemetry Beacon 22wpm
  • FT8 Telemetry Beacon 11.6bps
  • PPM Telemetry Beacon 138bps
  • USB/SSTV Robot36
  • USB/SSTV PD120

Planning a launch in September 2025 into a 536 km polar orbit from Haiyang Sea Launch Platform, Shandong, China

**The following frequencies have been coordinated.
Downlink frequencies:
-for H/U linear transponder 435.505 MHz, EIRP 24 dBm
-uplink: It is understood that terrestrial amateur stations will access the transponder on 21.320 MHz +/- 7.5 kHz

-for V/U linear transponder 435.540 MHz, EIRP 24 dBm
-uplink: for V/U linear transponder 145.860 MHz,

-for telemetry beacon 435.570 MHz, EIRP 23 dBm

-for V/U FM transponder 435.600 MHz, EIRP 24 dBm
-uplink: for V/U FM transponder 145.925 MHz,

-for GMSK telemetry 435.650 MHz,EIRP, 27 dBm

-for GMSK digital S/F transponder 435.700 MHz, EIRP 24 dBm
-uplink: for AFSK digital S/F 145.895 MHz,

-for multi-mode beacon 2405.500 MHz, EIRP 27 dBm.

Note: for the S/F transponder it seems that the AFSK in uplink is a typo as above in the entry is referred as GMSK transponder, no reference to AFSK.

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Just checked SpaceTrack and don’t see anything new that looks like it’s from this launch. Any info or even a guess on an orbit so we can listen for CAS-11?

On Celestrak:

OBJECT A                
1 65938U 25226A   25285.00220667  .00013044  00000+0  77470-3 0  9992
2 65938  97.6681 359.1341 0013867 281.6622  78.3051 15.11360625   147
OBJECT B                
1 65939U 25226B   25284.27394706 -.00005896  00000+0 -34699-3 0  9991
2 65939  97.6601 358.3928 0015890 294.4818  65.4754 15.11159167    20
OBJECT C                
1 65940U 25226C   25285.00227219  .00012351  00000+0  73609-3 0  9995
2 65940  97.6590 359.1351 0013776 279.4539  80.5133 15.11249265   132
OBJECT D                
1 65944U 25226D   25284.47235729  .00001093  00000+0  66968-4 0  9996
2 65944  97.6470 358.6280 0015449 299.0171  60.9511 15.12261527    45
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  • A rumor circulated that CAMSAT’s CAS-11 satellite would launch yesterday
    on the Gravity-1 rocket from a sea launch platform off the coast of
    Haiyang. Although the launch was successful and the orbital parameters and
    launch information match the IARU filing for CAS-11, it appears that the
    satellite was not on board.

AMSAT News Service 285

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@dl7ndr That’s interesting, thanks for the note!

I’m curious what is the AMSAT source for “it appears that the satellite was not on board.”, maybe a communication with the Chinese team or an other online source?

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Bob (N6RFM) sent me this link which list the 3 sats on that launch. So, I guess we continue waiting for CAS-11.

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BA1DU Alan told me that CAS-11 will be postponed until later next year.
The development progress is much slower than expected.

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