Posts by DB2OS

    Hier das vorläufige Tagungsprogramm (2 Tage!), kleine Korrekturen sind noch möglich...


    Datum Uhrzeit Uhrzeit Thema Referent
    Samstag, 9. November 2019 9:00 10:00 Kaffee und Kuchen
    10:00 10:15 Begrüßung Thilo Elsner, DJ5YM
    10:15 11:00 Es´hail-2 /QO-100/ P4A Start und Inbetriebnahme Peter Gülzow, DB2OS
    11:00 11:45 QO-100 im NB Betrieb, wie QRV werden Matthias Bopp, DD1US
    11:45 12:00 Beschaffung, Umrüstung und Transport der QO-100 Antenne für die Antarktisstation DP0GVN Michael Lengrüsser, DD5ER
    12:00 13:00 DATV-Betrieb auf dem QO-100 WB Transponder Jens Schoon, DH6BB
    14:00 17:00 AMSAT-DL Hauptversammlung (Gäste sind willkommen) AMSAT-DL
    17:00 18:00 Georg-von-Neumayer 3 Antakrtisstation, Aufbau und Aufgaben Felix Riess, DL5XL
    19:00 gemeinsames Abendessen (Ort wird während der Versammlung bekannt gegeben) Thilo Elsner, DJ5YM
    Sonntag, 10. November 2019 10:00 11:00 50 Jahre AMSAT Peter Gülzow, DB2OS
    11:00 12:00 ARISS - Amateurfunk auf der internationalen Raumstation ISS und AREx - das NASA ARTEMIS Project (Deep Space Gateway) Oliver Amend, DG6BCE
    12:00 13:00 Digitalbetrieb auf dem QO-100 NB Transponder Heiner Jürs, DD0KP
    13:00 Ende

    A look at the block diagram sometimes says more than 1000 words ;-)



    There is ony one single S-Band Uplink antenna dedicated to us and RHCP was the best choice.

    NB and WB path are completely independed, separated after the antenna via redundant paths.

    There is also only one dedicated feed for our X-Band Downlink.

    Since any commercial LNB use H/V polarization, this was the perfect solution to connect both NB and WB to the same feed and same antenna. Like on the commercial Sat-TV downlinks, we could also use the same frequency or overlapping frequencies just with different polarization.

    We always propagated the use of Dual-LNB in case you want to receive both NB and DATV at the same time and it costs almost nothing...

    It is about wireless to me, but I bet it is possible to do and something that Amsat as a governing body could operate for schools and colleges if they wanted to show the technology, and my questions were actually genuine. How would you authenticate licenced operators?


    Yes, I was somehow joking.. but technically it would be doable...


    We don't have authentication in the real hamsphere either, except for announcing our callsigns.. so a perfect simulation ;-)

    DB2OS That already exists. People making 'QSO's' via the internet (no, I am not talking about Echolink ; -) because they can't install an antenna or experience too much QRM.

    Not sure what you mean exactly... I know there is Brandmeister etc. on Internet and you can use it even without RF...


    I was talking about a virtual linear transponder with say 1 MHz bandwidth and "analog" tunig..

    enough room for SSB, FM, DSTAR, etc.. linear modes, digital modes..

    Even LEILA-3 with notch filter could work, or even better the STELLA with adaptive leveling of all signals ;-)


    So for what do we need QO-100 than?


    Gentlemen, I was joking !!! :D:D


    At least for me, our hobby still is about wireless radio..


    73s Peter

    There seems to be a lot of users with uplink only and completly depending on the WebSDR...


    Which brought me to the following idea:


    How about a "Virtual Transponder" in the cloud?


    Imagine a server creates a virtual passband and you can tune into it like with the existing WebSDR.

    Than imagine that you can transmit like with SDR-Console!

    Instead of actually radiating RF and receiving RF, everything is handled by Software on the Server and you are just streaming IQ data via internet in both ways.


    Does'nt this sound great? ;)

    Hi George,


    this is not official... it was an proposal/experiment by BATC ..


    The proposal didn't really work, the chat in WebSDR is still the better variant. Or why not Duplex RB-DATV?


    After recent experiences with FM stations overpowering the WB, our acceptance has declined. The proposal will not be pursued further. That's also why it will not be in the official bandplan.


    73s Peter

    Von der JARL FO-29 Kommandostation:


    Der FO-29 Transponder ist verfügbar, bis UVC in der CW-Telemetrie aktiv ist.


    Wie folgt UTC-Datum und Uhrzeit:


    10/5 06:40 15:00

    10/6 07:25 17:35

    10/12 05:30 15:35

    10/13 08:00 14:40

    10/19 07:45 14:25

    10/20 05:10 15:15

    From JARL FO-29 control center


    FO-29 Transponder will be available until UVC active in the CW telemetry. as follows UTC date and time.


    10/5 06:40 15:00

    10/6 07:25 17:35

    10/12 05:30 15:35

    10/13 08:00 14:40

    10/19 07:45 14:25

    10/20 05:10 15:15

    I think nobody expected these problems.


    I did.


    Having significant 'hands on' experience with SNG (satellite news gathering) in one of my former lives, and as former satellite co-ordinator of the Dutch government I spoke with several co-workers of Es'hailSat during IBC2018 and IBC2019 concerning 'how to deal with an 'undefined' user group'. They were flabbergasted ...


    Actually WE did!


    I'm not surprised that they were flabbergasted. These are mostly Sales people...

    I hope you did not scare them too much, since we are still hoping for a follow-up on Es'hail-3


    AMSAT-DL is not building linear transponders for the first time and I can assure you, that "uncoordinated multiple access" was our number one topic in the technical discussions! Already from the first day meetings with Es'hailSat and AMSAT-DL some 6 years ago, even before the manufacturer was selected.. Later on, we had several workshops and design reviews in Qatar and Japan regarding the implementation of these means. Except for TWT stage all other components of the QO-100 transponders are "non-standard" compared to their commercial TV transponders and in some cases specially re-designed to fulfill our requirements, including AGC and other functionalities which we will not describe here further for known reasons.


    There will be no damage to the satellite, but the owner of the satellite has an high (commercial) interest to extend the lifetime of the TWT. They are just getting nervous about what have happened recently.


    I think there is no need to discuss what we AMSAT or Es'hailSat could have done or should do..


    The message for the ham radio community is very simple: Stick to the Bandplan and follow the Rules!


    Be happy and thankful to the State of Qatar for giving us such a fantastic satellite and the opportunity to have the QO-100 transponders.


    operators using QO100 do know

    • where to point the antenna
    • which frequencies to use
    • which power is required


    and the easiest way to spread and share this information is not only via Twitter/Facebook/Chat, but on the transponder itself !! Yes, by You!