QO-100 Realtime Live DVB-S2 Decoding Success with very low SNR , using leandvb

  • This is Realtime live DVB-S2 Decoding done , without need to record .RAW file , its live and easy method by one click ! In this video i decoding 2MS symbol rate from wideband transponder of QO-100 beacon , you can decoding 1MS , 0.5MS , 333KS , 125KS symbol rate ! The lower Symbol, the faster speed for decoding! , the Amateurs operators on QO-100 Uplink DATV DVB-S2 at 0.5 , 333 , 125Ks , so its easy to Live Decoding Now ! With very low SNR ! , so the normal SDR can coverage wideband beacon of 2Ms symbol and all Ham uplink ! , if you have an SDR that can coverage 27.5 mb of bandwidth, so you can easy decoding Live a standard commercial satellite channels! But it need a high speed Pc . The softwares i use : Leandvb, LDPC .
    http://www.pabr.org/radio/leandvb


    For LIVE VEW AND DECODING DIRECTLY WITHOUT RECORD ANY FILE :
    rtl_sdr -f 742500000 -s 2400000 -g 10 - | ./leandvb --gui --inpipe 32000000 --nhelpers 6 --sr 2000e3 --sampler rrc --rrc-rej 30 --standard DVB-S2 --ldpc-helper ldpc_tool -v -d | vlc -

    you can change the frequency or symbol rate to any frequency you want to decoding !


  • (((((( For LIVE VEW DIRECTLY WITHOUT RECORD ANY FILE !! : ))))))



    rtl_sdr -f 742500000 -s 2400000 -g 10 - | ./leandvb --gui --inpipe 32000000 --nhelpers 6 --sr 2000e3 --sampler rrc --rrc-rej 30 --standard DVB-S2 --ldpc-helper ldpc_tool -v -d | vlc -

  • another method :


    for live recording .ts video format to TMP folder :




    sudo -s


    echo 32000000 > /proc/sys/fs/pipe-max-size




    rtl_sdr -f 742500000 -s 2400000 -g 10 - | ./leandvb --gui --inpipe 32000000 --nhelpers 6 --sr 2000e3 --sampler rrc --rrc-rej 30 --standard DVB-S2 --ldpc-helper ldpc_tool -v -d > /tmp/stream.ts



    then to run the .ts file just use this :



    vlc /tmp/stream.ts


    or:


    mplayer /tmp/stream.ts

  • for piping to the max you need to activate it in terminal :



    sudo -s

    echo 32000000 > /proc/sys/fs/pipe-max-size

  • dl7kay Hi, i run Lubuntu 16.04. . I was following the install guide on leandvb website, this failed. Removed everything and git cloned to github.

    Now on github, the process is completely different. What command should i issue to see a signal in VLC ?

  • dm4im : Use this installation guide here, please:


    http://www.pabr.org/radio/leandvb/leandvb.en.html#install


    After building the LDPC binary copy it into the same directory where the leandvb binaries are located. If you didn't change the paths it should be ../leandvb/src/apps


    Questions: Call me 🖒

  • Here's what i get now:



  • Did you do


    sudo -s

    echo 32000000 > /proc/sys/fs/pipe-max-size



    And did you copy the LDPC_tool binary into apps?


    Or: Did you compile both toolchains with the same user? In fact permission denied means wrong rights, too.


    Or: You can pn me a


    ls -l


    of the app directory.


    Or: After doing sudo -s I had to quit the root user again. Did you do that?


    The parameter


    --ldpc-helper ldpc_tool


    means that the external tool ldpc_tool will br called. I has to be in the app dir.

  • hello all,


    name: nico


    testing out the software in ubuntu....16.04 lts


    i am using a q-force 10 year old cpu with 1 core @2 ghz speed and 4 ram memory


    had problems installing leansdr , with the libiio missing and also no libX11


    i installed with synaptic all what i could find from libX11 and also from libiio


    after cleaning up and remove all directory , i had luck and no errors in the fresh install proces from leansdr/leandvb




    After building the LDPC binary i have also copy it into the same directory where the leandvb binaries are located. If you didn't change the paths it should be ../leandvb/src/apps


    this means all was copied from ldpc folder into leandvb/ src/apps


    still it not working after the rtl_sdr command to run , had errors


    i had to copy from the ldpc folder the ldpc_tool and leandvb to the standard home dir


    than it worked....


    for example the image from a uk station on 333ks with auto detection fec in h264 dvbs2



    the stream was not constant , but the picture quality was impressive


    it was tested out with mplayer and vlc , both worked


    not bad with very slow cpu pc


    yes , forgot the gain was best -g 25,4 , the -g 10 was quitte low for nb stations


    had also decoded 3b8fa in 500 ks


    the best thing from this software is that it find the fec automatic and the transmit mode 8 psk or qpsk and the locking goes vy fast


    a station in 8 psk was almost locked , the 8 dots symbol where on the constellation seen here on const screen , but 8 psk must have very strong signal.... but it works , no daught...


    thanks for reading .....73


    can someone tell if the streaming gives no errors more in the streaming procces with a very fast cpu??


    someone who could test this?


    good luck








  • did some test today for best offline decoding , this was my command


    open terminal 1:

    rtl_sdr -f 742455000 -s 2400000 -g 32 capture.iq


    : let the terminal 1 window open


    open a new terminal 2 :

    ./leandvb --gui -v -d -f 2400000 --sr 2000e3 --sampler rrc --rrc-rej 30 --standard DVB-S2 --ldpc-helper ldpc_tool < capture.iq > capture.ts


    let it also open (terminal 2 , do not close for 12 minutes)


    wait about 12 minutes to write the full time videocontent from beacon in the capture.ts file


    now close nr 1 en nr 2 terminal


    then open again a terminal : mplayer capture.ts


    i should playback without any errors

  • @dl9dac message


    i am also no expert in linux , will try to make some guide for ubuntu 18.04 or 19.04


    however there is still a change that you will need some libraries when they are missing on your cpu when building it


    good luck , nico de roo , on7ndr