Transmit digital television signals over Qatar Oscar 100 satellite

Introducing Adalm Pluto - The Full-Duplex SDR Transmitter Receiver

This page is the official rules established for satellite QO-100 broadband transponder usage, March 2020 edition. See the BATC website for the current version.

Due to the very large number of potential users, all transmitting stations should monitor the wideband spectrum monitor and the co-ordination chat window that has been established by AMSAT-DL and the BATC at https://eshail.batc.org.uk/wb/

Transponder Usage

As a general principle, the transponder should be only be used for short-duration tests and contacts.  The only long-duration (more than 10 minute) transmissions should be:

  • The TV beacon channel uplinked from Qatar or Bochum.
  • Video of the live proceedings of AMSAT and Amateur TV Lectures and Conferences of wide interest. Examples might include:
    • National AMSAT Conferences
    • National Amateur TV Conventions

The following content is unacceptable:

  • Recordings of events, or broadcast of events, not explicitly concerned with Amateur Satellites or Amateur TV
  • Transmission of any copyright material (such as movies or TV channels)
  • Repeated transmission of test videos unless essential for equipment alignment

The relaying of terrestrial Amateur TV Repeaters is discouraged unless the content is of exceptional amateur radio interest.

Transmission Power

All uplink transmissions should use the minimum power possible. QPSK transmissions should have a downlink signal with at least 1 dB lower power density than the Beacon – the web-based spectrum monitor enables users to set their uplink power to achieve this. Transmissions with symbol rates of less than 333 kS using 8PSK, 16 APSK or 32 APSK should use the minimum power density required to achieve successful reception.

Transmission Modes

Transmissions should use DVB-S2 where possible. For normal standard definition transmissions, 2 MS is the maximum symbol rate that should routinely be used.

To enable easy decoding the following DVB PIDs are recommended: Video 256, Audio, 257, PMT 32 or 4095, PCR 256 or 258. Service Name should be set to CallSign. PMT PIDs 4000 – 4010 should not be used.

On Wednesdays (UTC time), experimenters are encouraged to try other modes – perhaps 6 MS using the whole transponder for brief (less than 10 minute) periods. It is essential that users announce their plans on the chat room page, and always monitor it.

Experiments using unusual modes (for example ranging) should use the lower 1.5 MHz of the “Wide and Narrow DATV” Segment.

Beacon

The beacon transmits continuously (10491.5 MHz, DVB-S2, SR 1500 kS) to provide a test signal and to allow new users to precisely align their antennas.

Bandplan

QO-100 Es’hail-2 Wideband Spectrum Monitor

  1. Narrow DATV transmissions should be confined to the “Narrow DATV” section, but may use the “Wide and Narrow DATV” section if the Narrow DATV section is fully occupied.
  2. A maintenance uplink occupying 10494.0 MHz – 10497.0 MHz will be used very occasionally; users are requested to give it absolute priority when notified.
  3. Recommended spot frequencies for various usages and symbol rates are listed below.
Mode Symbol Rate Uplink Freq MHz Downlink Freq

MHz

Notes
Beacon 1500 kS 2402.0 10491.5 Beacon DVB-S2 FEC 4/5
Wide 1 MS 2403.75 10493.25 1.5 MS and 2 MS transmission should use this part of the band
Wide 1 MS 2405.25 10494.75
Wide 1 MS 2406.75 10496.25
Narrow 333 kS 2403.25 10492.75 Use these 14 frequencies for

500 kS, 333 kS and 250 kS

 

Use frequencies above 10497.0 first

                     Then every 500 kHz until
Narrow 333 kS 2409.75 10499.25
Very Narrow 125 kS 2403.25 10492.75 Use these 27 frequencies for

125 kS, 66 kS and 33 kS

 

Use frequencies above 10497.0 first

                     Then every 250 kHz until
Very Narrow 125 kS 2409.75 10499.25
  1. Uplink 2401.0 – 2410.0 MHz RHCP, Downlink 10490.5 – 10499.5 MHz Horizontal.

14 thoughts on “Transmit digital television signals over Qatar Oscar 100 satellite

  1. Christian,

    Congratulations, this is one of the Blog articles I’ve read about how to setup a DATV station for QO-100.

    Thanks for sharing with the community.

    73’s
    Alex EA4BFK

    (Traduction)
    Christian,

    Félicitations, c’est l’un des articles de blog que j’ai lu sur la façon d’installer une station DATV pour le QO-100.
    Merci pour avoir partagé avec la communauté.

    73’s
    Alex EA4BFK

    1. Merci Christian Superbe tuto !! A bientôt sur QO-100
      73 de ON1RC
      Chris

      (Translation)
      Thank you Christian Superb tuto ! See you soon on QO-100
      73 from ON1RC
      Chris

      1. Bonjour Christian
        Mais quel superbe outil de travail, moi qui suis totalement néophyte dans le mode DATVet dans l’utilisation du logiciel OBS.
        Me voici équipé pour comprendre le fonctionnement et pouvoir parfaire mon installation.
        Félicitations pour la qualité de tes tutos qui sans nul doute vont être un fabuleux tremplin à beaucoup pour créer sa station.

        73 cordialement salutations et au plaisir de te retrouver sur le satellite Q0-100. F3CJ

        (Translation)
        Hello Christian
        But what a great tool, I’m a total neophyte in the DATVet mode in the use of OBS software.
        Here I am equipped to understand how it works and to be able to perfect my installation.
        Congratulations for the quality of your tutorials which will undoubtedly be a fabulous springboard for many to create their station.

        73 cordially greetings and I look forward to seeing you on the Q0-100 satellite. F3CJ

  2. Merci beaucoup Christian.
    Des informations très précises et détaillées.
    Superbe.
    73 de Aitor F4VTB EB2AT

    (Translation)
    Thank you very much, Christian.
    Very precise and detailed information.
    Superb.
    73 of Aitor F4VTB EB2AT

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  4. Thanks for the wonderful guide. Very comprehensive. Thanks again for sharing your experiences. With gratitude 73 de Ros i4wrm

    (Traduction)
    Merci pour le merveilleux guide. Très complet. Merci encore de partager vos expériences. Avec reconnaissance 73 de Ros i4wrm

  5. Bonsoir Christian F5UII,

    Merci pour votre tuto, très instructif. J’ai échangé avec Pascal F4BRF et Nicolas FR4LI au sujet de la modification à base de 2 x 4N35 (montage vu sur le net pour l’ADALM PLUTO).L’idée, une commutation TX/RX pour la partie amplificateur SG-LAB depuis le PLUTO.
    J’aimerai avoir votre avis avisé sur le sujet svp. En vous remerciant par avance.
    Au plaisir de vous lire Christian F5UII.
    73 de Axel FR5GS

    (Translation)
    Good evening Christian F5UII,

    Thank you for your tutorial, very informative. I discussed with Pascal F4BRF and Nicolas FR4LI about the modification based on 2 x 4N35 (assembly seen on the net for the ADALM PLUTO) The idea, a TX/RX switching for the SG-LAB amplifier part from the PLUTO.
    I would like to have your opinion on the subject please. Thank you in advance.
    Looking forward to reading you Christian F5UII.
    73 from Axel FR5GS

    1. Oui, le logiciel SDR Console et également le firmware PlutoDVB d’Evariste F5OEO pilotent les sorties GPO0 et GPO1 lorsque l’on passe en émission. On utilise les 2 sorties car toutes les deux passent en émission à la mise sous tension du Pluto pendant environ 5 secondes.
      Commutation émission PTT sur Adalm Pluto SDR
      On trouve deux schémas permettant la commutation PTT, l’un à base d’optocoupleurs, l’autre à base de transistor et relais reed. J’ai choisi de mettre en œuvre la seconde technique, avec double circuit de commutation, permettant d’alimenter distinctement 2 sorties indépendantes. Une commande groupée sera certainement prochainement proposée. Tous les détails sur cette page.
      Il existe une autre solution, mais que je ne conseille pas au vu du risque engagé sur le Pluto. Il s’agit de celle qui consiste à détecter l’activité du bit0 du bus 12 bits du convertisseur numérique /analogique. Pour la curiosité, je vous laisse découvrir cette mise en œuvre de DH1NFJ sur ce site internet (langue allemande).

      (Translation)
      Yes, the SDR Console software and also the PlutoDVB firmware of Evariste F5OEO drive the GPO0 and GPO1 outputs when you switch to transmission. Both outputs are used because they both switch to transmission when the Pluto is switched on for about 5 seconds.
      Amplifier PTT control - Adalm pluto SDR
      We find two schematics for PTT switching, one based on optocouplers, the other based on transistor and reed relay. I chose to implement the second technique, with a double switching circuit, allowing to supply separately independent 2 outputs. A grouped order will certainly be proposed soon. All details on this page.
      There is another solution, but which I do not advise in view of the risk involved on the Pluto. It is the one which consists in detecting the activity of bit0 of the 12 bits bus of the digital/analog converter. For curiosity, I let you discover this implementation of DH1NFJ on this website (German language).

      1. Bonsoir Christian,
        Merci pour toutes ces informations. Inscription faite de mon côté pour la prochaine commande groupée (PTT Pluto). 73 de Axel FR5GS

        (Translation)
        Good evening, Christian,
        Thank you for all this information. Registration made on my side for the next group order (PTT Pluto). 73 from Axel FR5GS

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  7. Christian,

    Congratulations, for great work.

    Thanks for sharing with the community.

    Jose EA3HMJ

    (Translation)
    Christian,

    Félicitations, pour votre excellent travail.
    Merci d’avoir partagé avec la communauté.

    Jose EA3HMJ

  8. Bonjour Christian,
    Merci pour vos articles qui nous permettre d’avancer sur la construction de notre deuxième station DATV à l’Ile de la Réunion. Nous sommes actuellement actif sur QO100 en bande étroite.
    La station DATV est en cours de construction en suivant à la lettre votre tuto.

    Nous recherchons un système à base d’Arduino capable de mettre off le PA du SG Lab lors d’un SWR élevé et qui serait capable de faire les mesures de puissance OUT/IN. Ceci en utilisant les points de mesures en tension prévu à cet effet. Avez vous une idée si un Om c’est déjà penché sur la question.
    Par avance merci,
    Nicolas Dhiver
    FR4LI

    (Translation)
    Hello, Christian,
    Thank you for your articles which will allow us to progress on the construction of our second DATV station in Reunion Island. We are currently active on QO100 in narrowband.
    The DATV station is under construction following your tuto to the letter.

    We are looking for an Arduino based system able to turn off the SG Lab PA at high SWR and which would be able to make OUT/IN power measurements. This by using the voltage measurement points provided for this purpose. Do you have an idea if an Om has already looked into the matter.
    Thank you in advance,
    Nicolas Dhiver
    FR4LI

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  10. This is a great guide, helped me a lot. Merci!
    Ed PY2RN

    (Traduction)
    C’est un excellent guide, qui m’a beaucoup aidé. Merci !
    Ed PY2RN

    1. Bonjour Rudy,
      La carte exploite le changement d’état de la voie GP0, et GP1 qui, lui, bloque le passage à l’émission lorsque le Pluto démarre (GP1 actif en même temps que GP0 au démarrage). Elle est compatible avec les logiciels qui font commande le GP0 au passage en émission du pluto. C’est le cas en effet PlutoDVB d’Evarise F5OEO et SDRConsole de Simon G4ELI. Peut être d’autres le propose… ou le proposeront.
      D’après ce qui est indiqué sur le wiki de l’Analog Device, on doit pouvoir ajouter cette instruction (entre autres lignes) pour ajouter la commande automatique de la voie GP0.
      iio_attr -a -D ad9361-phy adi,gpo0-slave-tx-enable 1

      Bons essais. N’hésitez pas à partager vos conclusions ici.
      73 Christian

      (Translation)
      Hello, Rudy,
      The board exploits the state change of channel GP0, and GP1 which locks the switch to transmit when the Pluto starts (GP1 active at the same time as GP0 at start up). It is compatible with the software that controls GP0 when the Pluto is transmitting. This is indeed the case of PlutoDVB from Evarise F5OEO and SDRConsole from Simon G4ELI. Maybe others propose it… or will propose it.
      According to the wiki of the Analog Device, it should be possible to add this instruction (among other lines) to add automatic GP0 channel control.
      iio_attr -a -D ad9361-phy adi,gpo0-slave-tx-enable 1

      Good try. Feel free to share your findings here.
      73 Christian

  11. Wonderfull site and good OM thanks for all your time

    GRTZ the Alain ON7ATV

    (Traduction)
    Site merveilleux et bon OM merci pour tout le temps passé

    GRTZ le Alain ON7ATV

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