ISS Deployment (JAXA) J-SSOD#35 - 2026-02-03 08:20 UTC

[K4KDR]

Temporary NORAD ID	Satellite	Frequency	Notes	Deployed
VHF
98532	KNACKSAT-2	145.825 MHz	FSK 9600.0	-
98398	UiTMSAT-2	145.825 MHz	AFSK 1200.0	-
UHF
98532	KNACKSAT-2	400.630 MHz	FSK 9600.0	-
98397	LEOPARD	400.960 MHz	CW	-
98397	LEOPARD	400.960 MHz	GMSK 4800.0	-
98396	CoRAL	401.140 MHz	FM	-
AMATEUR UHF
98531	GXIBA-1	437.300 MHz	FSK AX.100 Mode 5 9600.0	-
98398	UiTMSAT-2	437.375 MHz	CW 20.0	-
98398	UiTMSAT-2	437.375 MHz	GMSK 4800.0	-
S-Band
98397	LEOPARD	2279.100 MHz	BPSK	-

From https://x.com/JAXA_Kiboriyo/status/2014538069089911294

… we have -6- sats scheduled for deployment from the Kibo Module (ISS) on 03-Feb-2025.

With help from 6 CubeSats to be deployed from the “Kibo” Japanese Experiment Module on Tuesday, February 3, 2026 | JAXA Human Spaceflight Technology Directorate , ITU, IARU, SatNogs, & Google, my notes so far:

===========

Gxiba-1
take pictures of Mexican active volcanoes
98531
https://upaep.mx/gxiba
IARU Sat Coordinator
9k6 GFSK downlink using AX100 mode 5. Planning a JAXA deployment from the ISS in June 2025. 437.300 MHz has been coordinated

CoRAL
401.14 (max BW = 20 kHz)
Testing Distributed Telemetry Networks and Inter-Satellite Links (ISL) through
Internet of Things technologies

KNACKSAT-2
98532
145.825
400.63
https://insted.kmutnb.ac.th/KNACKSAT-2.html
Camera Mission
APRS digi
IoT Store & Forward

HMU-SAT2 (Teruteru)
light messages from space using LEDs

UiTMSAT-2
437.375 MHz 20 wpm CW beacon and 4k8 GMSK AX25 Telemetry and mission data
145.825 MHz coordinated
Camera mission
Store-and-Forward mission (VHF-up / UHF-down)
APRS digi (VHF-up / UHF-down)

LEOPARD
400.96 (45 kHz max BW)
2279.1 (408 kHz max BW)

[dl7ndr]

Database entries:

• Gxiba

• HMU-SAT2

• KNACKSAT-2
  KNACKSAT-2.pdf (294.2 KB)
  (Beacon (400 MHz), Digipeater (9k6), Data Submission, Dashboard, Rewards)
  

  

• UiTMSAT-2

• LEOPARD

[K4KDR]

Greetings!

For anyone who would like to test their RX & decode setup for KNACKSAT-2, the Team has kindly shared a sample I/Q file (32-bit float, samp-rate 1250000) as well as an even easier file to test with, demodulated 48k audio.

That URL is:

knacksat-iq-wave - Google Drive

… and if you have obtained an API Key for use w/ the ‘KnackSat Packet Forwarder’, you can confirm that it is working correctly for you as well.

Here’s an example of the sample frames decoded in GNU Radio:

… and now that we know the source host name being used (or destination if you prefer), an AX.25 check block can be used to not send false/trash decodes to neither the Team nor SatNogs:

… and finally, the Team’s Packet Forwarder indicating successful uploads:

… Thanks very much to the KnackSat-2 Team for providing all the info, tools, & sample files so that we can know that we are setup properly to receive their satellite!

One more thing! If you would like to bookmark:

https://dashboard.knacksat.com/

… you can see a list of the decodes uploaded to the KnackSat-2 database.

[K4KDR]

Regarding the KnackSat-2 Telemetry Forwarder, please be sure to download the latest version from

knacksat-packet-forwarder - Google Drive

… and as of v4.0.7, the Team has confirmed that our decodes are being uploaded correctly. However, there is a lingering “Bad request: Invalid AX.25 frame format” error message in the log that can be ignored.

[fredy]

From the LEOPARD team:

Here is an online document for logging and decoding CW LEOPARD CW Decoder Operation.xlsx - Υπολογιστικά φύλλα Google

Also there is a decoder for windows:
LEOPARD CW Decoder.zip (4.1 MB)

[K4KDR]

Here is the deployment livestreams:

Small Satellites Deployment J-SSOD#35 (Gxiba-1/ CoRAL/ KNACKSAT-2) /「きぼう」から超小型衛星放出 J-SSOD#35｜1回目配信

-and-

「きぼう」から超小型衛星放出 J-SSOD#35｜2回目配信/ Small Satellites Deployment J-SSOD#35 (HMU-SAT2/ UiTMSAT-2/ LEOPARD)

[alpha_adhito]

Gxiba-1 and CoRAL

KNACKSAT-2

[K4KDR]

We had a frequency for CoRAL, but this is the first I’ve seen about the modulation details:

Wouldn’t it be nice if all the space agencies posted a list like this when they are deploying satellites?

[EU1SAT]

GXIBA-1 Active and Demodulated!

9k6
Interval 1 min.
2 Frames uploaded

[alpha_adhito]

HMU-SAT2, UiTMSAT-2 and LEOPARD also deployed at 10:55UTC. Beautiful formation flying captured by ISS camera.

[fredy]

I’ve missed the launch time, I thought it was tonight UTC, I’m making active the satellites in DB and scheduling in the Network.

[fredy]

Here are the TLE, it is the ISS TLE from space-track.org changed to follow the tempoary NORAD IDs from SatNOGS DB:

GXIBA-1
1 98531U 98067A   26034.04958920  .00010142  00000-0  19604-3 0  9999
2 98531  51.6308 243.5964 0011016  59.0626 301.1443 15.48354905550966
UiTMSAT-2
1 98398U 98067A   26034.04958920  .00010142  00000-0  19604-3 0  9990
2 98398  51.6308 243.5964 0011016  59.0626 301.1443 15.48354905550967
KNACKSAT-2
1 98532U 98067A   26034.04958920  .00010142  00000-0  19604-3 0  9990
2 98532  51.6308 243.5964 0011016  59.0626 301.1443 15.48354905550967
HMU-SAT2
1 98403U 98067A   26034.04958920  .00010142  00000-0  19604-3 0  9997
2 98403  51.6308 243.5964 0011016  59.0626 301.1443 15.48354905550964
LEOPARD
1 98397U 98067A   26034.04958920  .00010142  00000-0  19604-3 0  9999
2 98397  51.6308 243.5964 0011016  59.0626 301.1443 15.48354905550966
CoRAL
1 98396U 98067A   26034.04958920  .00010142  00000-0  19604-3 0  9998
2 98396  51.6308 243.5964 0011016  59.0626 301.1443 15.48354905550965

[fredy]

I’ve updated the first post with the satellites entries sorted by frequencies and finished scheduling the Network for the next two days.

I’m sorry I missed the deployment, I was tired from traveling and i didn’t do the right timezone maths…

[PE0SAT]

TLE Update GXIBA-1

GXIBA-1
1 98531U          26034.58392332  .00000000  00000-0  19604-3 0    02
2 98531  51.6308 241.5297 0011016  59.0626  41.8164 15.49249862    02

# 20260203.45-20260203.58, 11 measurements, 0.070 kHz rms

Jan | PE0SAT

[K4KDR]

The 1525utc pass over the Eastern U.S. was nothing heard from KNACKSAT-2 on 400.630 nor 145.825 and nothing heard from CoRAL on 401.14.

There was a VERY weak signal about where CoRAL should have been, but it looked to be much too narrow for 9k6. Will keep an eye on that.

P.S. - just noticed that an earlier decode from some other object in the 401 MHz satellite band got uploaded as a decode for CoRAL. Sorry about that. SO much nicer when we have payloads w/ AX.25 addresses so that all the false hits can be filtered out.

[PE0SAT]

TLE Update CORAL

CORAL
1 98396U          26034.58391738  .00000000  00000-0  19604-3 0    00
2 98396  51.6308 241.0238 0011016  59.0626  41.9183 15.48794783    09

# 20260203.45-20260203.59, 30 measurements, 0.108 kHz rms

Jan | PE0SAT

[PE0SAT]

No signals received from KNACKSAT-2 on 400.630.

Jan | PE0SAT

[dl7ndr]

Knacksat-2’s 400 MHz mode should be FSK 9.6 kbps and for the digipeater

The APRS-DP active schedule time will be announced once the satellite
health check is complete.

according to Apiwat, HS4SCI via email.

[N6RFM]

Same here earlier as well in North Texas.

[K4KDR]

Ok, thanks to SatNogs observation

SatNOGS Network - Observation 13328501

… it appears that the CoRAL 9k6 downlink on 401.140 is the AX.100 variety!