Posts by DB2OS

Quote from HB9SKA

Hallo Peter

I want receive with my radio, not via SatNOGS. Otherwise I could also receive via WebSDR. But that's not my thing.

Thomas,

you misunderstood me.. I tried to help you and give you a hint how to use MMSTV with your recorded Wave-file !!!

The SatNOGS is my own station and not a WebSDR. I wanted to decode the recorded file of my own station, nothing more, nothing less.. just read the instructions in my original post and you will see how you can play a recorded file within MMSTV..

73 Peter

Hallo Thomas,

Du kannst doch MMSSTV auch ohne Soundkarte benutzen:

MAI-75 SSTV activity planned for Aug 4 and 5, 2020

Gruß Peter

Hi Manuel,

Yes - the WB+24MHz connector should be the marked one.

In the the most recent batch of LNB's it is now reversed because the LNB internal layout was changed.

New LNB:

[Blocked Image: https://shop.amsat-dl.org/wp-content/uploads/2021/01/modifizierter-LNB-v2-300x289.jpg]

Anyway, you can't destroy if you connect wrongly.. without Reference Clock the LNB will simply not work..

73s Peter

Hello,

in order to better organize the documentation of the various AMSAT-DL hardware and software projects, we have now created a dokuWiki especially for this purpose.

here the link --> https://wiki.amsat-dl.org

This should hopefully be clearer and easier to update than directly on the homepage or here in the lexicon.

Special thanks also to the authors, Matthias DD1US and Kurt dj0abr for providing and maintaining the contents.

73s Peter

Quote from on1arf

It's a bit strange as there does exists a system called 'rsid' (*) that does allow easy identification of a digital signal.
Why do people not use this feature?
Do people not know that this exist? It is a standard feature of gqrx, so I guess other SDR software will also have it.

(*) http://www.w1hkj.com/RSID_description.html

Hi Kristoff,

I assume most people on QO-100 might even not know GQRX and thus not about RSID.

I also hear about RSID for the first time, but the idea behind sounds good.

Perhaps Kurt can implement this in HSMODEM too.

73s Peter

Quote from PE4WJ

Thanks Peter!

I agree there is nothing wrong with QO-100 - our investigation mostly focused on the frequency accuracy of the transponder LO to determine the source of the frequency offset that was observed, not so much on its frequency stability.

Hi Wouter Jan,

Thanks! Yes - absolutely correct regarding frequency accuracy and stability.. indeed both are covered and referenced above, while originally analyzing the short term frequency stability, an offset of ~70 Hz in frequency accuracy has been indeed observed.. I should have better emphasized this...

73s Peter

Thomas,

the AMSAT-UK information is from the launch service provider GK-launch and other sources.

You can also check here: https://community.libre.space/…2021-03-22t06-07-utc/7523

73s Peter

from AMSAT-UK, see https://amsat-uk.org/2021/03/22/soyuz-2-launch/

The Soyuz‑2.1a LV was launched from Baikonur in Kazakhstan on March 22, 2021. The following satellites, operating in frequency bands allocated to the amateur satellite service have been coordinated by the IARU Satellite Frequency Coordination Panel:

• Beesat‑5

• Beesat‑6

• Beesat‑7

• Beesat‑8

• FEES

• SMOG

• GRBAlpha

• KSU_Cubesat

• DIY‑1

• STECCO

• CubeSX-HSE

• CubeSX-Sirius-HSE

• Orbicraft-Zorkiy

• NanoSatC-BR2

Operating in frequency bands allocated to the amateur satellite service without IARU frequency coordination is KMSL. Additional satellites may follow.

Operating in frequency bands allocated to the amateur satellite service while the IARU Satellite Frequency Coordination Panel has declined coordination are UNISAT‑7 and WildTrackCube-Simba.

Further information including the IARU coordinated frequencies at http://amsat.org.uk/iaru/

I merged the latest thread into this already existing thread, because this is actually known and nothing is wrong with QO-100.

Please see previous posts and also check the analysis made by Dani EA4GPZ more than 1 year ago.

https://destevez.net/?s=QO-100

Quote

At least here in ON-country- there are in fact situation where encryption is not only allowed but even mandatory.

1. - emergency communication carrying information about individuals.
2. - to remotely control amateur-radio infrastructure,
3. - to remotely control amateur-satellite radio infrastructure

There is a general misunderstanding between 'security', 'safety', 'privacy' and 'authentication'

In particular for Point 2. and Point 3. encryption is absolutely not required. On all P3-Satellites we never used encryption, but authentication.. There was no need to hide the commands, but indeed you wanted to make sure that only real command stations could execute commands. So instead of encryption, the protection was using a kind of trustable signature..

73s Peter

Yes - protocol description and other details must be placed in the public and easily accessible.

In the past this was mainly publishing articles in widely available media, for example magazines etc.

Nowadays Internet is indeed very well suited if it can be easily found, for example via Google or GitHub, etc...

73 Peter

Hi Kristof,

Quote

If the message itself cannot be decoded -because it is encrypted emergency communication or some new experimental mode-, the listeners have no way to verify if that is indeed a message from that station.

And this would be illegal anyway and I assume the user community will quickly start to find out what it is and start counter actions, as we have seen in the past.. quite successful actually.

I assume that any proposal to experiment with new modes here on the transponder will follow the guidelines, international and local regulations, therefor it needs to be fully documented before any experimental transmissions takes place, to allow others to decode. Otherwise it would be treated as illegal..

73s Peter

Hi Kristoff,

As far as I know, the proper standard "identification signal" given by ITU and local regulators for "experimental" modes is either speech or morse code for the callsign. It may also be possible to use other digital formats as long as they are well-known standards in amateur radio, easy to identify or decode. For example the "callsign" field in AX.25 Packet Radio became such a standard and Morse code identification was only required in the very early days.

Indeed we are looking forward to see and learn more about your experiments than..

73s Peter

Quote from hb9bla

I opened my Opticum LTP-04H and it looks very different from the ones you have..

Did you buy it recently??

It's seems to be an very old one, obviously with DRO instead of XTAL and PLL..

You can scrap it...

Edit: Just noted.. on the sticker: yours is "blue" line, the correct one is "red" line.. so it's not the same..

Version 3 February 2021 – The following updated DATV (DVB-S2) bandplan and guidelines are designed to enable the most efficient use of the QO-100 wideband transponder (WB) for all amateur radio satellite users. Please make sure that you understand the guidelines and follow them accordingly. The use of DVB-S2 as the most efficient transmission mode is advised.

https://amsat-dl.org/en/p4-a-w…and-operating-guidelines/

or for direct Download: QO-100 WB Transponder Bandplan V3

this morning ISRO launched several satellites with frequencies in the amateur satellite spectrum, unfortunatly all of them seems to be without IARU coordination..

• SDSAT 3 at 435.500 Mhz (uncoordinated)
• GHRCESat at 437.500 Mhz (uncoordinated) and at 436.000 Mhz (uncoordinated)
• JITSat 1 at 437.500 Mhz (uncoordinated) and at 436.000 Mhz (uncoordinated)
• SSIETSat 1 at 437.500 Mhz (uncoordinated) and at 436.000 Mhz (uncoordinated)

I've also got my BETA tester pre-order announcement by direct eMail

But here is something more interesting to learn about the antenna itself:

Enjoy, 73s Peter

Hello,

here is the link for tomorrow live stream of Mars2020 until cruise stage separation from Bochum

I will start the stream about 1h before cruise stage separation at 20:38 UTC, which is 10 minutes before EDL..

73s Peter

You are seeing a live spectrum view from Tianwen-1 telemetry transmitter received by the 20-Meter Antenna at the Bochum-Observatory in Germany. Tianwen-1 ("questions to heaven," or "questioning the heavens") is a Mars mission by China consisting of an orbiter and rover. It launched in July 2020 and enters Mars orbit on 10 February 2021 around 12:00 UTC. The rover will not land until May. Mission Lead: CNSA
Follow us on Twitter: https://twitter.com/amsatdl
For more details about our antenna: https://amsat-dl.org/en/20-meter-ante...

Tune in into our live stream and listen to the Emirates Mars Mission (EMM) Hope Probe when it arrives at Mars. We will track EMM with our 20-Meter Antenna at the Bochum Observatory about 2 hours before orbital insertion. Fingers crossed for HopeProbe!