First activity on QO-100 from French Guiana

As usual, I have the opportunity to return to Guyana at the end of October to participate with the radio club FY5KE RACK (Radio club of Kourou) at the CQ WW DX SSB 2019. a few days before the weekend, from 22 to 25 October 2019, and this as much as time allows, we hope to make the first contacts via the new geostationary satellite Qatar Oscar 100, from French Guyana.

The celestial mechanics

Kourou is very close to the equator, at 5 degrees latitude in the northern hemisphere, and longitude 52 degrees west. The geostationary satellite positioned at 26°East longitude with a distance of 41,400 km from Kourou. To be able to focus the satellite from Kourou, we will have to point the sky full East with only 2.8 degrees of elevation above the horizon. This will not necessarily be obvious, especially if we find tropical vegetation on our way. The Skew angle is remarkable, it is very close to 90°: the polarized wave at the departure vertically by the satellite arrives practically in a horizontal way.

  • Latitude: 5.1745°
  • Longitude: -52.6865°
  • Locator: GJ35PE


  • Azimuth: 91.0° (109.3° magnetic)
  • Elevation: 2.8°
  • LNB Skew: -84.7°

The operators

We will be two operators, who will try to activate FY for the first time on QO-100: Florent F4CWN and Christian F5UII.

The equipments

Satellite dish

The dish used will be “limited” to an 80cm television offset dish.


We are bringing with us two transceivers, of two different technologies.

The F4CWN equipment: Very compact Up/Down converter

• IF : 431 MHz, 2w drive
• Outpout power P3dB 40W
• Input NF : 1.5dB
• Rx Conversion Gain : 30dB
• Single ADF4351 based Local Oscillator
• Size : 13x12x8cm box
• Weight: 1.7 kg
• UpConverter/DownConverter/PA F6BVA Design


QO-100 Compact Transceiver – Block Diagram

Compact satellite transceiver for Qatar Oscar 100

Dual Band feeder

Compact satellite transceiver for QO-100

Thanks to F6BVA who has made the design, and also to F1GHB, F1VL, F4BXL, F5AQC, F5BUU, F5NZZ who participated to the success of this project.

The F5UII equipment: Transmitter / receiver of SDR technology

• Full Duplex  SDR Transmiter Receiver : Lime SDR Mini
• Output power P3dB 2,5W
• Amplification : 31dBm (CN0417 + EDUP AB007)
• Dimensions: box of 24 x 10 x 5.5 cm
• Weight: 0.8 kg



SDR QO100 Transmission and reception

LimeSDR Mini Full Duplex

CN0417 Analog Device

LNB feeding by Tee bias

Activation schedules

Unfortunately, there is no specific activation program, as the main objective of this week in French Guiana is not traffic via the geostationary satellite, but first and foremost the implementation of the FY5KE station for the CQ WW DX Contest on 6 bands, in SSB. Nevertheless, we hope to find some slots available between October 22nd (~23 UTC) and October 25th to make the very first contacts since FY on QO100. We apologize to those who will not have the opportunity to contact us….

Real-time news

You can get news from us by following the publications made through the @f5uii twitter account.

4 thoughts on “First activity on QO-100 from French Guiana

  1. Hello 🙂

    i hope you will be QRV on QO-100 after 15:00-16:00 UTC to give a chance to working people also a chance to work FY.

    GL and best DX, Franz

    Bonjour 🙂 J’espère que vous serez QRV sur QO-100 après 15:00-16:00 UTC pour donner une chance aux travailleurs.

    1. Bonjour,

      Pour information, un compte-rendu de l’activité sera publié dans la revue Radio-REF (membres du REF) de décembre 2019, et également dans le Journal des membres de l’AMSAT-DL en décembre 2019.

      Bonne lecture
      Christian F5UII


      For information, a report of the activity will be published in the December 2019 edition of the radio-ref magazine (REF members), and also in the December 2019 issue of the AMSAT-DL Journal in December 2019.

      Have a good reading
      Christian F5UII

  2. Hi Christian,
    I am Ram VU2GRM,
    I have configured Lime Mini SDR and using SDR Console v3.0.20 software. It is working fine on SSB. With a virtual cable I am able to receive SSTV with MMSSTV S/w. On transmit, a drift is seen on the signal and no one is able to lock on to my signals. Lime is connected to the PC through a externally powered hub. Could you please let me know how to solve this.
    I am also keen on using this on CW. How can I do this ?

    I have fan over the Lime and temperature is around 32-35 deg. Have not provided any heat sink as seen in your QRZ page. Should this be ok ?


    Bonjour Christian,
    Je suis Ram VU2GRM,
    J’ai configuré Lime Mini SDR et j’utilise le logiciel SDR Console v3.0.20. Il fonctionne bien sur SSB. Avec un câble virtuel, je suis capable de recevoir SSTV avec MMSSTV S/w. A l’émission, on voit une dérive sur le signal et personne ne peut se verrouiller sur mes signaux. Le LimeSDR est connecté au PC par un hub alimenté. Pourriez-vous me faire savoir comment résoudre ce problème ?
    J’aimerais également utiliser ce système en CW. Comment puis-je faire cela ?

    J’ai un ventilateur sur le LimeSDR et la température est d’environ 32-35 degrés. Je n’ai pas fourni de dissipateur thermique comme vous pouvez le voir sur votre page QRZ. Est-ce que cela devrait aller ?

    Je vous remercie

    1. Hello Ram,

      The LimeSDR is subject to drifting when there is air movement on the VCTXO-equipped side. As you can see on the pictures of my article, the fan (small fast fan) blows into the housing above the LimeSDR, the FGPA side being on top. The air extraction is done without a fan at the other end of the box. In steady state, frequency variations are not disturbing.
      Moreover to work in CW, I advise you to use the F8EHO Pascal EHOCw software . This software, very complete, allows you to generate morse code. It offers the possibility to send predefined sequences by keyboard shortcuts, but can be directly used with a morse manipulator connected to a serial port of your computer. I mentioned it in my talk at the beginning of March (page 30 of the presentation in French)

      Hoping to have given you some guidance. Looking forward to the next QSO on QO-100!
      73 Chris

      Bonjour Ram,

      Le LimeSDR est sujet à dériver lorsqu’il y a des mouvements d’air sur la face équipé du VCTXO. Comme vous le voyez sur les photos de mon article, le ventilateur (petit ventilateur rapide) souffle dans le boitier au-dessus du LimeSDR, le coté FGPA étant au-dessus. L’extraction d’air ce fait sans ventilateur à l’autre bout du boitier. En régime établi, les variations de fréquences ne sont pas gênantes.
      Par ailleurs pour trafiquer en CW, je vous conseille le logiciel de F8EHO Pascal (EHOCW). Ce logiciel, très complet, permet de générer du morse. Il offre la possibilité d’envoyer des séquences prédéfinis par touches de raccourcis clavier, mais peut directement être utilisé avec un manipulateur morse branché sur un port série de votre ordinateur. Je l’ai évoqué dans ma conférence de début mars (page 30 de la présentation en français)

      Espérant vous avoir guidé quelque peu. Au plaisir d’un prochain QSO sur QO-100 !

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