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Monday, 4 March 2019

notes on satellite LNB (eshailsat 2, qo-100) information as I learn and try to understand it

Wide band TV receiving 

https://forum.amsat-dl.org/index.php?thread/101-software-dvb-s-demodulator/&pageNo=1
Current Version: 2.0.9
Download Link: http://v.1337team.tk/dvb-s_gui_amsat.zip
also need to install VLC media player
url you need to put in vlc is udp://@:8888
10492.500MHz S2 2msps qpsk 2/3

Install sdr sharp
set to spy server network (source)
in the space below paste the following address: sdr://80.229.173.194:55557
click on play, yu now have live feed of the narrow band, direct to your sdr client.

for viewing the TV try some of the links below
http://www.vivadatv.org/tutioune.php?om_id=DL9SAD&station_id=1 

http://www.vivadatv.org/tutioune.php




Universal LNB’s work by the receiver selecting one quarter of the channels at any one time. It does this by alternating the voltage between 13V and 18V which will enable the LNB to switch between Horizontal and vertically polarised signals. A 22kHz tone then switches the LNB from a low and high band. Hence a quarter of the channels at any one time. Vertical Low, vertical high, horizontal low, horizontal high.

Satellite signals are beamed down from the satellites in space to the satellite dish at a frequency which is far too great to be contained by the coaxial cable. At this point the signals are oscillated to fall down to a frequency band – Satellite intermediate frequency (IF) which sits just above the UHF band used for terrestrial TV and 4G internet signals and has a bandwidth of around half of that which was previously available before being oscillated. So the universal LNB will oscillate one half of the frequency band at a great rate than the other half, hence the high and low band.

Ku-Band, which is divided in a low band from 10.7GHz to 11.7GHz (Lo: 9.75 GHz) and a high band from 11.7GHz to 12.75GHz

on eshailsat 2 we are looking at  a receive frequency of 10489690 MHz take away the Local Oscillator (LO of 9.75GHz) gives us 739Mhz. 739 is where we point our SDR or receiver.


GNURADIO can be used on hackrf etc as an ssb transmitter using blocks created by DL9SW
https://www.qrz.com/lookup/DL9SW

Phaselocking to Es’Hailsat-2 / QO-100’s upper PSK400 beacon


raspberry pi 2 sdr cat control to a 817-nd
SAT CONTROLLER SDR NANO

For the wideband TV stuff you can start reading on here, looks like to just get the beacon (wide signal) you change the crystal in the lnb and tune your sky box. more later when I have time to test
https://wiki.batc.org.uk/Receiving_Oscar_100_DATV_signals


narrow band RX LNB can be bought cheaply from here:
https://www.amazon.co.uk/Goobay-67321-Universal-Single-LNB-grey-white/dp/B00DO49CVC/ref=dp_ob_title_ce

Bias-t
https://www.sotabeams.co.uk/blog/biast-for-lnb-a-few-notes/

Decoding TV beacon
https://www.pabr.org/radio/qo100sdr/qo100sdr.en.html

record IQ (raw) file from gqrx, then process with leandvb and ldpc_tool

./leandvb  --f32  -f 2400e3  --sr 2000e3  --sampler rrc  --rrc-rej 30  --standard DVB-S2  --ldpc-helper ldpc_tool  -v  -d  --gui < /tmp/gqrx_YYYYmmdd_HHMMSS_742ffffff_2400000_fc.raw  > /tmp/video.ts

./leandvb  --f32 -f 750e3  --sr 333e3  --sampler rrc  --rrc-rej 30  --standard DVB-S2  --ldpc-helper ldpc_tool  -v  -d  --gui < gqrx_20190319_220745_748051800_750000_fc.raw > x5.ts

Testing live streaming direct to vlc

airspy_rx -f 742.500 -a 10000000 -h 14 -p 0  -r /dev/stdout |  ./leandvb --s16 --standard DVB-S2 -f 10000000 --sr 2000e3 --cr 2/3 --ldpc-helper "./ldpc_tool" --drift --hq --gui --strongpls |vlc -


**be aware when copy and paste lines, I had issues with " chnaged to @ and | turned to ~**