PSE HELP ME - TX LIGHTING ZONE OF QO-100 -> solved QRT

  • Hello...

    I have a problem here ... I've been trying to connect to the QO-100 for 4 weeks!!!!


    I tested with 1 to 20 watts (Kuhne UP2424B) and a 90cm satellite dish (CAS90 - Kathrein).

    I can only get over the QO-100 with a very very weak signal! Not even max 0.5-1db above the noise only with 20watts on the webSDR:eshail.batc.org.uk . You can only see the signal with a dish larger than 120cm!


    I got the same result with a DuoBand-Feed 2.4 / 2 x 10 GHz from BaMaTech and a Helix antenna with 5 turns.

    I also tested the upconverter UP2424B directly on the feed with a 1 meter cable! Always the same result!


    I have a clear view to the satellite! I receive the CW-beacons here with S9 + 4 dB!


    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 !


    I have checked the transceiver, cables and antennas and had the UP converter checked by Kuhne electronic in Germany.


    At the moment I'm at a loss! I do not know how to continue... !?!?!


    I hope the problem is not the illumination in the TX-uplink here at my location!


    The picture of my station in the appendix...


    Note! You can answer/contact me here in English or directly via email in German! Thank you in advance!

  • Hello Andreas,

    your nice documentation did not show what cable type and cable loss is on the TX side between the PA and the helix.

    Did you have measured the TX power nearby the feed? Return loss from the feed?


    I don't believe in a flaw in the 2.4 GHz RX antenna diagram of QO-100.


    There is a station in Asiatic Russia, R0AU, there QO-100 is 4 degrees above the horizon, with no problems.


    Here a KGSTV Picture ....




    73 de Robert

  • Hello Thomas...

    the QO-100 has the uplink at 13cm with a dish and he has a 3cm downlink with a dish ... right?

    The illumination/footprint on 3cm is not the same as on 13cm because there are always technical deviations.

    It's about the edge zone and the sensitivity of the uplink of the QO-100!


    Wouldn't it be possible that the sensitivity of the uplink in the marginal zone is not the same everywhere or that there are deviations in the calculation and simulation?


    My question is there any practical experience or test results from the AMAST with the footprint here in the north of 13cm?


    Calculations and simulations are one thing. The practice on site can look completely different again.


    Please don't get me wrong ... I'm just saying, what if?


    I have the above problem and I am looking for answers and a solution ...

    I ask myself the question... where are the 20db from my station on the QO-100???

  • Hello Andreas,

    How far is the powermeter on the Kuhne-uplinkconv blinking, full range output LED's? Assuming full lighting bar means 20w out? Did you measure the current when in tx? PTT line ok?

    On the picture you have 1500mW at feed, so normally this should be good enough to have a better signal when using a 90cm dish.


    Best 73's,Jerry

  • Hi Robert... thanks!


    I connected the upconverter to the dish with a piece of coaxial cable (1m). Measurement cable from the 6GHz spectrum analyzer! Return loss is 20 to 25 db with the feed and helix antenna. In terms of measurement technology, I have no abnormalities here. All measured values were normal!


    До свидания и оставайтесь здоровыми!

  • Hi Andreas,

    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

  • Hello Jabi...

    yes, the configuration of the UP converter is correct. IFin=144MHz.

    I have now tried everything and had the upconverter and the BaMaTech Poty tested again in Germany.

    All measured values are okay and the connection via QO100 works without problems with the lowest power!


    I'm giving up the QO100 project here. My special permit ends on March 30, 2021 with 1.5 watts!


    NOTE!

    If anyone here in the forum is interested in a Kuhne UPconverter MKU UP2424B last current HW version and a Poty from BaMaTech 1x2.4GHz & 2x10GHz H/V, then write to me. Date of purchase in November 2020 with invoice.


    You can find my email address on my website or on QRZ.com


    I really am very sorry!

  • SA2BFO

    Changed the title of the thread from “PSE HELP ME - TX LIGHTING ZONE OF QO-100” to “PSE HELP ME - TX LIGHTING ZONE OF QO-100 -> solved QRT”.