Posts by HB9EKO

    Hallo Wolfgang,

    ich verwende für den Uplink einen FT-891 auf 10m mit 70cm Transverter von, mit dem ich dann einen 13cm Transverter von SG-Lab ansteuere. Ich habe die Version mit TCXO, damit lässt die Stabilität nichts zu wünschen übrig. (In älteren Beiträgen hier im Forum war die Stabilität anscheinend mal ein Thema) Längere Durchgänge in SSB oder auch Betrieb in FT-8 ist damit problemlos möglich, ohne dass ich eine Frequenzdrift bemerkt habe. Die Signalqualität ist gut, und im Gehäuse hat es noch genug Platz um einen Bias-Tee unterzubringen. Ich lege damit beim Senden ein 12V Signal auf das Kabel zum SG-Lab Transverter, um damit die PTT zu schalten.

    73 Jens

    Hi Geert,

    when I want to test something then I use a spot close to the upper beacon, around 10.489.980 or so, there is hardly any traffic there.

    Especially when changing settings, hardware or trying to optimize the setup, since most paople's QO-100 setup is somehow experimental, there's an obvious requirement for testing, since monitoring the UL TRX is not aleays what you hear on DL. I don't understand why people have problems with other people testing. Nobody is forced to listen to somebody else's test signals. There is enough space on the transponder for eveybody.

    73 Jens HB9EKO

    I started with a SG Lab transverter and a 75cm dish. It was enough for SSB QSOs (I saw my signal approx. 5-6 dB below beacon level), but not very efficient in breaking pile-ups. Upgrade to a 1m dish got me a couple of DB extra.

    I upgraded with a SG lab PA, but in order not to exceed the beacon level, I had to reduce the output power of the PA. Depends on what you intend, you may not need a PA.

    73 Jens HB9EKO

    The VOX is always active. As long as you just use SSB, it's not necessary to do anything with the PTT.

    However, at CW speeds higher than 15 WPM or so, my setup tends to "eat" the first dot (no dashes), i.e. either the PA's or the transverter's VOX doesn't react fast enough. If you plan to use CW more than occasionally, I'd recommend to wire the PTT.

    73 Jens

    Hi Enzo,

    I have locked my LNB to a GPSDO. When I switch everything on and the GPSDO has not been running for a week or so, I have a similar effect for a few seconds before the GPSDO is locked to the satellites. (The waterfall looks similar) Thus, to me it looks like an unstable reference frequency.

    73 Jens HB9EKO



    any tested models for buck converters as I am afraid of high noise or is that something not concern?

    I use a cheap Chinese buck converter to supply my SG-Lab PA…042311.0.0.27424c4dUd5DT4

    No issue with noise from the DC-DC converter, at least not in the DL receive frequency range.issues with noise so far. Output voltage, and thus output power of the PA can easily be adjusted.

    My setup: I have my SG-lab transverter, PA and DX-Patrol bias tee in a outdoor enclosure close to the dish, all on a common power supply. From that box, 15m RF cable to a RTL-SDR stick (for DL) and FT-817 (for UL), 8m cable to the 12V power supply,

    73 Jens, HB9EKO

    Giebt es eigendlich Alternativen wie zb sowas wie SDR Console V3 für linux??

    Und was möglichst noch auf einem Pi läuft ich habe noch nichts gefungen.

    Hallo Oliver,

    ich kenne noch CubicSDR. Keine Ahnung wie das auf einem RasPI läuft, aber auf meinem PC ist die CPU Auslastung ähnlich wie bei GQRX. Ich habe es mal ausprobiert, bin dann aber bei GQRX geblieben. Die Benutzeroberfläche ist etwas anders, das Ganze ist wohl Geschmackssache.

    73 Jens HB9EKO

    Now GQRX as master and the FT-817 as slave for the sync is still on the wishlist. So the next step is probably understanding the code of this tool...

    Easier than expected. I found out that without modifying anything in the code, I can simply swap the CAT information of RX and TX, as well as the start frequency entries. This makes the FT-817 follow the RX frequency of GQRX. Done some cosmetics by replacing "TX" with "Master" and "RX" with "Follower" and changed the default entries accordingly. Now the tool does what I expect it to do, The "Follower" follows the "Master" regardless what is TX and what is RX.

    73 Jens HB9EKO


    as promised, I would like to provide an update:

    Now I just have to find the time to continue .... / Jetzt muss ich nur noch die Zeit finden, weiter daran zu arbeiten....

    i finally found some time to follow up on this subject.

    In a first attempt, I tried to run Satcontrol on my Shack PC instead of a Raspberry Pi. Unfortunately, I did not manage to run it on my Kubuntu 20.04. Python 2 is not available by default for this Distri, and my attempts to install Python 2 with instructions from the web did not result in Satcontrol and Python 2 cooperating with each other. Porting it from Python 2 to Python 3 turned out to be something major, so I put this on hold for the moment.

    I spent a rainy weekend learning some python basics and understanding how I could code what I want, but then I realized it will take me much more time to learn how to use libraries to create a GUI for the programme and hamlib to read and write the frequencies from GQRX and the FT-817. So I put this on hold, too.

    Shortly before ordering the mentioned issue of Funkamateur, I found a tool called "QTrackUplink" : and decided to give it a try. After spending a couple of hours setting up QT Creator and understanding how to use it, I managed to compile the source code on my PC and got it working.

    This is almost what I was looking for. I can tune UL and DL with a basic offset. After that, the RX frequency in GQRX follows the TX frequency when I change it at the FT-817.

    I'm happy with this for the time being. Now GQRX as master and the FT-817 as slave for the sync is still on the wishlist. So the next step is probably understanding the code of this tool...

    73 Jens, HB9EKO

    Hi Andreas,

    Are there any active stations with the same equipment here in the north or further north of me in SM, OH, LA, UA? Who has similar observations or problems here in my direction?

    My Locator is JP94UX !

    The northernmost OM I had a QSO with was LA6OP in JP67WJ. I don't remember how much power he used, but the QSO was in SSB, his signal was considerably above the noise. So there must be another reason why it's not working for you, it's definitely not the latitude.

    73 Jens HB9EKO

    The Python program you can download here:

    Maybe that on your system some additional packages need to be installed. On the complete Raspberry image everything is already prepared.

    Thanks a lot, I will give it a try

    Hallo Jens, ergänzende Informationen:

    • Für den DL wird ein rtl-Dongle verwendet; ich verwende einen mit TXCO.
    • Für den UL wird über einen USB/Seriell-Wandler ein geeigneter Transceiver angesteuert. Einzige Bedingung: der Transceiver muß in dem Programm rigctld (aus der Hamlib) gelistet sein.

    Besten Dank, dann weiss ich, dass sich bei Bedarf eine Heftbestellung lohnt.

    Now I just have to find the time to continue .... / Jetzt muss ich nur noch die Zeit finden, weiter daran zu arbeiten....

    73 Jens HB9EKO

    Hi there,

    thank you for your replies / Danke für Eure Antworten.

    It looks to me like there is no "out of the box" solution for my specific setup, but I got some good inputs that might help me to get towards what I'm looking for, provided I find the time.

    Es schaut so aus, als ob es keine fertige Lösung für mein spezielles Setup gäbe, aber mit Euren Hinweisen habe ich ein paar gute Ansatzpunkte wie ich weitermachen kann, wenn ich die nötige Zeit dafür finde.

    Not really adressing your questions, but i wrote some small Python program to 'organise' the CAT control of the FT-817. See…ster/ for more info.

    Maybe this helps you in some direction.

    vy 73 de Johan, PA3ANG

    Hi Johan,

    This looks similar to what I'm looking for, I would have to modify this script to read the RX frequency from GQRX rather than a FT-817.

    I have limited programming skills, since I wrote my last programs decades ago in Turbo Pascal. In the "External applications" section of, I found some tools like gqrx-hamlib that also go into that direction, however I failed to get it running on my machine so far.
    Maybe it's a sign that I should invest the time and learn some python and/or go deeper into details with my Linux setup? :/

    in Heft 12/19 der Zeitschrift "Funkamateur" ist genau dieses Problem behandelt worden von DG7BBP unter dem Titel "Sende-Empfangs-Synchronisierung per Software beim QO-100-Betrieb".

    Dieses Lösung läuft bei mir auf einem RaspberryPi 3 stabil.

    vy73 de Hermann-Josef

    Hallo Hermann,

    kannst Du mir ein paar Details nennen? Setzt diese Lösung ebenfalls einen RTL-SDR Stick für den DL und einen externen TRX für den UL voraus? Wenn ich damit weiter komme würde ich das Heft bestellen.

    Maybe this will work for you: SAT Controller SDR Nano

    Hi Frank,

    I am sure it would work, but since my PC in the shack is already connected to the FT-817 and gqrx is perfectly working, I would like to avoid setting up a separate hardware only for SAT control.

    I would appreciate if I could use the software/sourcecode. However, reading other related threads in this forum, I understand that Satcontrol is only available as a RasPI image and not generically for installation on any Linux machine. You certainly have your reasons for distributing the solution only in this way.

    Thanks for all the hints, I will update this thread when I make some progress. / Danke für all die Hinweise, ich werde diesen Thread aktualisieren, wenn ich Fortschritte mache.

    73 Jens HB9EKO

    Hi there,

    has anybody successfully managed to synchronise the UL and DL frequencies of a RTS-SDR and a FT-817 with Hamlib on Linux?

    On the RX side with my RTL-SDR, I can use GQRX or CubicSDR which are both fine.

    It gets tricky when I try to hook the software up with my FT-817 CAT control:

    In GQRX, there are some python scripts available which are supposed to link GQRX with hamlib. I did not manage to install them on my machine running Kubuntu 20.04, since they require an older version of QT.

    CubicSDR also looks quite nice and it has some TRX control functions included. However, they seem to be made to use CubicSDR for a panadapter with a TRX. Proper documentation does not seem to exist, and when playing a bit with the respective functions, I did not manage to set my TX frequency on 70cm to anything without CubicSDR setting the same 70cm frequency on the RTLSDR-stick :(

    Has anybody got an idea how to approach this subject with either GQRX or CubicSDR??

    73 Jens HB9EKO

    Hi Nick,

    being active in SOTA myself, I know very well how it feels like to struggle for the 4 QSOs. I will watch out for your activations to chase you. I don't have a portable setup for QO-100, but will gladly chase you if I'm at home during your activations. Having said that, this is more likely on the weekends or after work, even on the days when I can do home office, i can't always be QRV.

    73 Jens HB9EKO