Posts by AMSAT-DL

    Effective immediately, we are opening the QO-100 NB transponder to general contest operation in the upper mixed-mode range.

    see also:

    Updated band plan

    valid: from 4 April 2021

    Contest Zone (CW and SSB)

    Uplink area 2400.370 – 2400.490 MHz
    Downlink area 10489.870 – 10489.990 MHz

    Of course, the usual QO-100 NB transponder guidelines also apply here. Therefore, the bandwidth should still be limited to 2.7 kHz and the transmitting power should be reduced to the necessary level, i.e. only as much power as necessary should be used.

    Experimental Multimedia Beacon

    The attentive observer will not have failed to notice that the upper limit of the mixed mode range is now 10489.990 MHz. This is because the upper CW beacon at the end of the band will soon be changed to an experimental multimedia beacon, based on DJ0ABR’s AMSAT-DL HS Multimedia Modem.

    Positive experiences

    In the last few months, a number of activity competitions (challenges or contests) have been held. However, after initial reservations, these activities and the way they were conducted were viewed positively by the majority. Due to further requests, we have now decided to designate a suitable frequency range on QO-100 for such activity competitions, which allows a more orderly and undisturbed coexistence of supporters and opponents of such competitions.

    The “unwritten” law

    Until now, there was an “unwritten” law that, as a matter of principle, no contests should be carried out via satellites. Some still know it as lore from the early days of OSCAR satellites almost 50 years ago! This had technical reasons, some of which are still valid today. For example, previous OSCAR amateur radio satellites and also CubeSats tend to have very limited resources, i.e. low bandwidth, small batteries and low-power solar cells. Excessive load on the linear transponders, for example, repeatedly leads to unplanned shutdown in OSCAR-7. AMSAT-NA has reconfirmed this upon inquiry and still does not wish to have contest operations over AO-7.

    We are in a more fortunate position with the first QO-100 AMSAT geostationary transponder on the Es’hail-2 satellite. Again, we don’t have unlimited resources at our disposal, but with large powerful solar generators and higher battery capacities, we are much more relaxed. LEILA will also help if someone is using excessively high transmitting power.

    From a technical point of view, there is therefore currently no reason to prevent contest style operation, albeit within a limited scope, on QO-100.

    We expressly point out that each owner and operator of an amateur radio satellite owns the house right, as by the way with each terrestrial repeater also. Therefore, each operator decides for himself whether or not to allow contest operations on his amateur radio satellite. In case of doubt, the permission of the respective AMSAT organization or the owner of the satellite should always be obtained beforehand!


    With this decision we hope that this will also contribute to an increase in activity on QO-100 and broader interest among radio amateurs in the QO-100 footprint.

    Downside, youll need over 10Watt FM to get a desent S9 R5 signal...

    In stead of the 4 watt needed for a similar USB signal...

    Hi Benno,

    This is already the reason.. FM is the most ineffective method on satellites and we just don't want to promote this among other technical reasons. We also have had abuse in the past using strong FM on both NB and WB.. There have been a period of experiments using FM as a back channel, but it was not feasible for the above reasons and that's why we banned FM in general on QO-100.

    73s Peter

    All attendees are invited to join the virtual user meeting taking place at 17:20 CEST (15:20 UTC) on the narrow band transponder. You are invited to announce your participation in advance via WB tpx chat on [1] (please set you nick Name with "/nick N0CALL" to your callsign) or the YouTube chat on [2]. We will collect all the pre-registrations and call you one by one on 10489.830 MHz using the callsign DK0SB. As soon as the list is processed we go split and listen 10 up for any other user.




    Der eBay-Link taucht weiter oben mehrfach auf und funktioniert... wo ist das Problem?

    Wenn jemand es hier aber überstrapaziert (wie geschehen), dann müssen wir korrigierend eingreifen.

    Wir verdienen hiermit auch kein Geld und stellen das Forum kostenlos zur Verfügung.

    In general, we ask not to post any commercial or trade offers in this forum.

    There is nothing wrong with individual offers for purely personal and non-commercial reasons, but here too there should be no price discussions and a discreet approach.

    Ideal zum neuen DownConverter V3d passt natürlich ein von AMSAT-DL fertig umgebauter LNB, d.h. modifiziert für eine Referenzclock direkt gespeist aus dem Down-Converter und dort durch einen hochstabilen OCXO oder TCXO+GPS erzeugt.

    Weitere Details sind der Beschreibung des DownConverter V3d auf unser Webseite zu entnehmen.

    Wichtig: die externe Referenz liegt nur am "WB" Eingang des Konverters an und muss dann entsprechend auch mit dem oben gekennzeichneten Anschluß des LNB verbunden werden!

    Hier im Shop:

    a small reminder for given reasons:

    Remote operation of an amateur radio station via QO-100 is only permitted if the station belongs to the operator himself and is operated at his own location. He must always have full control over the station and in particular be able to switch it off immediately if, for example, interference occurs. Special cases of unmanned and automatically operating stations require both permission from the operator of the space station, in this case represented by AMSAT-DL, and special permission from the regulatory authority responsible in the respective country. The international and national legal regulations must always be complied with by the operator. The above agreement is in accordance with AMSAT-DL, AMSAT-UK, QARS and Es'hailSat.