New DXpatrol "Groundstation" now Full-Duplex !

  • Hello,

    i just found a new DX-Patrol toy on their website, they call it QO-100 Groundstation. Other than again there is no way to toggle RX/TX by a wire or switch , the manual says some things like how easy it is to use and the like. I heard someone on QO-100 say he is using the DX-Patrol QO-100 groundstation and he can NOT receive while transmitting. :/ There is no reference in half- or full-duplex in the manual. Anyone have info?

    73, Martin

  • Tnx for the pictures Rob !.

    DXPatrol did not respond to my request for pictures :-/

    • On the first pcicture - there is an unpopulated battery next to the GPS unit? How long will the GPS fix take?
    • On the second picture - the board is mounted slanted in the case or is this an optical illusion?
    • What are your experiences with the ground station? The VOX is working fine? Also with CW?

    Thanks in advance Rob!


  • Hello Martin,

    looking at the manual of the QO-100 Groudstation of DX-Patrol indeed it shows that the transverter is working only simplex.

    AMSAT-DL has made very clear for a long time than full duplex operations is requested by users who want to use QO-100.

    DX-Patrol is making money by leveraging the investment others have made by implementing the QO-100 ham radio satellite
    and they should respect the rules given by the operator of QO-100. Yet it looks like they are simply ignoring it.

    I think this is very disappointing!

    We can already today see the problems many people, who are using simplex operations, have to demonstrate proper operation.
    They talk over each other frequently without noticing. In pileups it is quite easy to distinguish those with a proper full-duplex setup
    and good operating skills from the others.

    Hopefully many radio amateurs will understand that this transverter is not compliant to the requested operation mode on QO-100
    and will thus choose one of the many other better solutions.

    Kind regards


  • Hello Dieter,

    • It seems indeed a upopulated place for a battery, see picture. GPS does take a looooong time to fix >5 min
    • Optical illusion due distortion of the wide angle lens on the camera
    • VOX working suberb in SSB, CW not tried. Overal i am pleased with the ground station. Its a grab and go for portabel use of the oscar 100. No build up heat in the unit. You have to use the enclosed LNB because the DX patrol goes straight to 70 cm.

    73's Rob, pa3eke

  • Hello Martin,

    Good point, indeed no duplex facility in the unit. You have to find a solution for your self. I have a second dish with RTL stick and raspberry PI and RTL_TCP server. I am synchronizing the Icom 705 with SDR console and Omni rig. In the field I can monitor by using the websdr and a phone. But for sure a duplex facility is missing. A build in downconverter to 2 meter can do the trick but it’s lacking

    73 Rob

  • Hi Guys,

    use a modern SDR-Concept and all the trouble is gone. Full duplex, easy tuning, synchronize with the PSK_Beacon, only one oscillator for tx-stability, tx-equalizer, envelope compression, spectrum display, two tone signal for linearity tests, what else do we need? Don't be afraid in front of digital technologies. You are not alone. Don't hesitate to use it. If nessecary, you get help. The terminal program from G4ELI is free of charge. From my point of view this is very remarkable.
    Have fun.

  • Hello

    I think the operator is more responsible for being simplex or duplex at the sat instead off people who sell the stuff. I use mostly my simplex station with a websdr on the background( on smartphone or pc) instead off my other setup and had never complains about being of freq.

    When there is a dx station active, and not working split, why so much duplex working stations are to high or to low on his freq??? Their stations not calibrated correctly? +-30% stations are off freq! This is not the case when the dx station is working split because you can call wherever you want.

    Allways complains about being simplex or duplex, why not complaining about all the stations being much stronger then the beacon? That's also a 'rule'.

    Best 73's, Jerry

  • DB2OS

    Changed the title of the thread from “DX-Patrol new "Groundstation" no Full-Duplex?” to “DX-Patrol new "Groundstation" no Full-Duplex!”.
  • Hello, I got the new GS from DX-patrol monday.

    A few remarks about the duplex, yes the unit is not duplex, so what.

    advantage: if i turn on 70cm and hear a station in downlink, I know i am on the correct uplink.

    I have been listening a few weeks on QO-100


    I see the tuning carrier from a lot of stations going over the band till they are plus minus on the situation they want to work, not good

    I hear a lot of stations up to a few hundreds of Hz above and below the station they want to work, not good

    I hear a large number of stations who are extremely loud (just above the beacon level), sound to me they want to see when Leila kicks off,, not good

    There is nothing wrong with QO100 simplex groundstation, on the contrary, the whistling and hola is not necessary anymore....

    Have I got full duplex, yes (otherwise i could not see the whistlers going across the band).

    How was it done?

    I split the RX signal coming from the LNB to a SDR stick (the splitter has a DC by pass on one port so that LNB works OK)

    Using SDR consoles V3 get radio and stick nicely synchronised.

    A few more things about the QO100-GS:

    - it is vox operated, 2 VOX (one for PA and one for transvertor), both inside

    -there is provision for a hard line PTT, (F6-1 F6-2 connector), short them out for PTT.

    One thing is that you might need to connect the external PTT of the amplifier to the F6-1 line aswell

    The lock (from the OCXO takes just abt a minute.

    The lock from the satellite takes a few minutes.

    Now let the flames come :huh:

  • No flames, just my 2 cents:

    A few remarks about the duplex, yes the unit is not duplex, so what.

    It violates the rules set up by Amsat when used as advertised, that's what. No mention of simplex in their advertise, why? Do they know things the buyer shouldn't? If i was a clueless buyer, i'd feel betrayed pretty soon. And by watching the signals on qo-100 one may sense that not all, but some, dx-patrol users are clueless. That's why they listen to the promises by D-P and believe inconsistent statements.

    if i turn on 70cm and hear a station in downlink, I know i am on the correct uplink.

    Well, that is what the vast majority of users does . They link their receiver to their transmitter. I've been listening since early 2019, it got a LOT better over time. Only few user don't.


    Your observations all relate to operator skills.

    How come you have a full-duplex setup, when there is nothing wrong with the simplex setup?

    I stick out my neck a lot farther than i should, but couldn't hold me back. It sure will turn out i should have. Oh my.. :/

    73, Martin

  • Martin,

    The RX setup (SDR-RTL stick) is used as wideband RX monitoring.


    I see the whole band and where there is activity.

    I see the tuners drifting over the band and see where they stop,.

    And the unit does not violate any rules at all.

    It all depends on how it is used, so down to operator.

    (just like those transmissions that are stronger than the beacon)

    If you use a nice sdr (with the added advantages) you play nice.

    ps1: I have made ZERO QSO on the QO100 bird, playing just on RX for a long time.

    ps2: when I saw the unit advertisement, it was clear to me that it was simplex unit.

    I sold my seperate dx- patrol up down convertor (144/432) , which was full duplex, but to much cabling, GPSDO, seperate amp etc etc

    Main reason for getting the DX-patrol GS, that it had all in a box, up/down/gpsdo, and its small, very small size to take in hand luggage.

    I even got the dxpatrol helix antenna as the size compared to poty and LNB is smaller.

    I considered DXTO from India (as that one has a 28MHz IF) which would have been cheaper on the IF rig , but price +taxes scared me off.

    Now just need to get a small dish antenna that will fit the luggage as well (after the covid pandemic)

    And to stay in the sat footprint when picking a location.


    • Official Post

    I think Johan was misunderstood because he did not tell us his whole station with SDR stick. Full duplex operation is an important rule for satellite operation and "Simplex" is a red cloth in this context. But I think also as Martin, that a new user think "Ah fine, it is a complete ground station and I can plug in the antenna and talk over QO-100". You know the result...

  • as time passes the 1st mods on the grounstation have been done.

    My unit has external ptt control added already.

    At the moment i'm looking to mod the rx circuit to have the rx splitter inside so that the sdr stick can be put inside the box.

    The backplane of the box has room left for a usb receptable.

    Would be less cabling .. and an answer to the duplex question.

    • Official Post

    Can we stop this discussion? Rules are Rules.. an the Rule is if you want to use QO-100 you need to be "full-duplex" capable.

    Yes - it's the shooter who kills people with a gun. So does the manual tell you, please respect the guidelines?

    It's quite funny that a unit is sold as a "PC-free", but you need a Laptop or Internet to check/monitor your own signal?

    This isn't funny. Actually it's sad that this is advertiued and sold this way. :thumbdown:

    Again - please respect the rules!

  • Well, a whole bunch of mods to make a unit usable that is sold as "plug 'n play" , right? Add RTL-Stick & Laptop, add PTT, put RX-Splitter inside, add USB..

    Ok, this is my last post in this thread. Again i "lean out of the window too far" as we say here. Will stop now and adjust to the overall mindset: Who cares...