An open letter

This isn’t the first time this topic is brought to our attention but after reading this call I felt obliged to share one of the important parts and a link to the original posting.

Original quote:

“According to the ITU Radio Regulations for the Amateur and Amateur-satellite Services, “Transmissions between amateur stations of different countries shall not be encoded for the purpose of obscuring their meaning, except for control signals exchanged between earth command stations and space stations in the amateur-satellite service.” A strict interpretation of this rule means that the specifications of all digital protocols used by Amateur stations should be publicly available, so that anyone is able decode the data. The use of protocols with undisclosed specifications can be seen as a try to obscure the meaning of the data.”

Source: By Dr. Daniel Estévez, an open letter about ESEO telemetry specifications.

LilacSat-2 Telemetry

LilacSat-2 Telemetry 23-09-2015 17:10 UTC

When you want to decode the LilacSat-2 telemetry you have to dive in to the world of *nix and GNURadio. Now I do have a lot of experience with *nix but GNURadio is every time a difficult road. But Persistence pays off.

Decoded packet:

****byte_corr = 0
* MESSAGE DEBUG PRINT PDU VERBOSE *
()
pdu_length = 112
contents =
0000: a2 54 39 00 bb a1 01 0f 09 17 11 10 29 5f 00 01
0010: 00 00 00 09 00 00 00 00 00 03 1a 05 0f cb 13 4c
0020: 26 7f 39 02 0a 1a b3 09 a2 19 c0 0a 00 00 00 00
0030: 20 05 c0 00 00 55 00 09 05 08 05 d0 d0 d0 e2 00
0040: 55 01 ec 0e 37 0f fc 0f 99 01 9c 1e 20 01 11 00
0050: 10 00 10 00 10 00 ff 3e 4d cb ff 13 f8 ff 12 00
0060: 02 00 a6 00 bd 80 31 01 00 00 00 00 aa 49 f5 8d

A brief summery:

I made with the help of SDR# and my FUNcube Dongle Pro+ SDR receiver an IQ file at 23-09-2015 17:10 UTC. Installed GNURadio with the help of the following script www.sbrac.org/files/build-gnuradio on Linux Mint.

When this was successful I cloned the gr-lilacsat source from github and compiled the gr-lilacsat source. After that I changed the lilacsat GNURadio front-end so it would accept an SDRSharp IQ recording as input.

lilacsat-2-gnuradio-decode

After that only some small changes to get the front-end up and running and connect it via localhost udp sources to the BPSK 9600 demodulator block.

I got the following confirmation: BG2BHC Great! Length is OK and the 5th and 6th bytes aa/bb a1 means that the packets are beacon packets created by OBC A/B

Second decode but this time real time with a RTL-SDR dongle. We are getting somewhere.

realtime-rtl-lilacsat

Download the IQ recording so you can test with your GNURadio environment

RS-39 (CHIBIS) invitation

From UA3XBU, origin: CHIBIS invitation

We invite all radio amateurs of the world to take part in the reception of the last signal the RS-39. Signals will be transmitted at a frequency of 435365 MHz, CW. As part of the call signals microsatellite and 16 parameters telemetry signals. TM information is transmitted at intervals of about 15 seconds has 3-4 index letters and three digits parameter.

The observations in the form of audio files will be accepted at the address plis@kaluga.ru. Participants will be awarded diplomas…

Original posting by Vladimir at DK3WN Satblog

ZAcube-1 Telemetry decoder

The ZAcube ground station have made a Decoder application available to decode the satellite telemetry.

ZAcube decoder

The application receives KISS encoded messages from a TNC and decodes the messages to understandable values. Configure the application by using the drop down boxes to select the serial port that your TNC is connected to and set the baud rate for your TNC and click connect. MixW and a virtual serial port emulator can also be used with the decoder application.

Download location: ZAcube decoder

MASAT-1 designated MagyarSat-OSCAR-72 (MO-72)

Masat-1 ModelMASAT-1 designated MagyarSat-OSCAR-72 (MO-72)

OSCAR Number Administrator Bill Tynan, W3XO reports, “Congratulations on the successful launch of the MaSat-1 Cubesat that the team at Budapest University of Technology and Economics have been responsible for designing, building and testing.

“Since you have met all of the requirements for being issued an OSCAR number, including coordination through IARU and requesting an OSCAR number, I, under authority vested in me by the President of AMSAT-NA, do hereby name MaSat-1 as MagyarSat-OSCAR-72 or MO-72.” Bill concludes, “I, and all at AMSAT-NA wish MagyarSat-OSCAR-72 great success in fulfilling all of its mission objectives.”

[PE0SAT thanks Bill Tynan, W3XO for the above information]