Posts by ha7dcd

    For best performance i modified today sample rate of rtl_sdr to 300000 and now i can see perfect the beacons. 1MHz would be too mouch for RPi to handle regarding the 8 clients that i set the max users.

    In my case i have center_freq=739675000 and shown_center_freq=10489675000.

    Also posted online on for about two weeks now

    73! de YO9HZN!

    unfortunately any special sampling speed will make you trouble... as Andras told me (the author of OpenWebRX) the best is to set 1024000 sampling rate. Thats processed the best by the rlt_sdr chain.

    I'm using RPi 3, without any issues with this setting (RPi 2 or older has somewhat lower performance)

    Yeah, as other told before me you need to use this command:

    shown_center_freq = 10489790000

    in my case I set the receiver frequency to this (universal LNB):

    center_freq = 739790000

    Hmm... I thought my online setup went wrong, or the heavy wind rotated my dish :) Glad to hear that might not a local issue, I was seeing no signal at all too.



    Lucky Peter ;)

    I guess we have to wait and see under real working conditions how unmodified LNBs would work.

    73s DB8TF

    I confess that my LNB is already modified (will edit this in my previous post) It has the original xtal inside but the plastic cover is broken in many places and the metal part exposed to the external world. This might a good explanation why I have so strong fluctuation up and down (+it's raining here)... Thanks for checking that!

    I have a feel that might extra thermal insulation layer(s) of the LNB could drastically improve this. I learnt that from G0UPL Hans, when he shared his OCXO development experiences in case of WSPR mode:


    When you see signals but not the expected patterns or only one of the two, you are likely pointed to the wrong satellite. This can easily happen as other satellites used beacons on almost the same frequencies, and are located e.g. at 31.5e and 19.2e.

    It is easier when you have a DVB-S(2) receiver as you can verify the satellite you are pointed to by checking the TV programmes you receive.

    When you are checking from Europe (i.e. not from the target area of these satellites) you cannot receive most programmes, but e.g. on 11996 MHz Horizontal 27.5MS/s 3/4 FEC you can receive a strong transponder with Arabic versions of news programmes. This is not from Es'hail-2 but from another Arabsat at 26e.

    Hi Rob,

    Thanks for the detailed answer! I made another effort and realized that I made a mistake: I didn't changed polarization while jumping from the upper to the lower frequency beacon (right now I need to rotate my LNB by hand...:) ) this is why the lower freq beacon's side bands was not showing up (buried in noise). Just right after I rotated the LNB by hand it's magically moved up from noise :) So I was on the right bird but wrong polarization... (V instead of H).

    I've put up an online stream for you guys (perhaps sporadically turns down, an experimental setup, changed my Inmarsat setup to this temporary):
    OpenWebRX + RPi 3 + RTL-SDR V3 + Inverto LNB

    (edit: the LNB is somewhat modified, was opened once and the plastic cover is broken so the metal part is exposed to air)



    Dear All,

    Made my first reception attempts and looks like got the 11205 MHz beacon (Hungary, Budapest). I see something on the 10706 MHz part as well but suspicious that not seeing side bands (may just my signal too weak?). It was a fun to me as my first Ku band SAT dish adventure :) Satellite AR android helped me but still was not easy. Using an old, abandoned and rusty analog sat TV dish, Inverto universal LNB, DIY bias tee + Signal Hound (later RTL-SDR V3 and OpenWebRX live stream)