PS
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Actually what I did here was a bit different I had already added the Astra 1 19E transponder parameters from kingofsat.net into xdipo, selected it in the xdipo browser with middle mouse, and then you can move the dish for maximum pitch of the test tone in xdipo. One swing, right on, fix screws, ready.
10 seconds, use bluetooth headset from PC audio. Last time that was needed was after a huge storm some year ago when it blew the dish a bit off-center, fixed the screws a bit more after that.
Now there are 2 LNBs, different bands, one extra taped against the other... Tape has stayed in one piece all year...
Was also doing some weather sat reception tests at 137.xxx MHz, with a slim-jim antenna.
From my own help file: ~# cat how_display_commands_weathersat.txt
-------------------- #cat noaa_15_137.62_MHz_5_weather.wav | aplay -r 44.1k -f S16_LE -t raw -c 1 #cat a2.wav | aplay -r 60k -f S16_LE -t raw -c 1 #cat a2.wav | aplay -r 60k -f S16_LE -t raw -c 1
# record weathersat as mp3 /root/compile/pantel/rtl-sdr/librtlsdr-0.5.3/build/src/rtl_fm -d 0 -F 9 -M fm -E deemp -f 137912500 -s 44.1k -r 44.1k -l 0 | \ lame -r -s 44.1 --bitwidth 16 -m m - - | \ tee -a /mnt/sda5/video/movies/satellite/noaa_15_137.62_MHz_4_weather.mp3 | \ mpg123 -
# record weather sat as wave -E wav not supported in my rtl_fm ###/root/compile/pantel/rtl-sdr/librtlsdr-0.5.3/build/src/rtl_fm -g 49.6 -d 0 -F 9 -M fm -E wav -E deemp -f 137912500 -s 60k -l 0 /mnt/sda5/video/movies/satellite/a3.wav # will be raw file at 60 kbps /root/compile/pantel/rtl-sdr/librtlsdr-0.5.3/build/src/rtl_fm -g 49.6 -d 0 -F 9 -M fm -E wav -E deemp -f 137912500 -s 60k -l 0 /mnt/sda5/video/movies/satellite/a3.wav
# test if signal in mp3 xine noaa_15_137.62_MHz__weather.mp3
##cat a2.wav | aplay -r 60k -f S16_LE -t raw -c 1 ##cat a2.wav | sox -t raw -r 60k -e signed-integer -b 16 -c 1 - aq1.wav rate 11025
# make 11025 file from mp3 mpg123 -r 11025 -w sig2.wav noaa_15_137.62_MHz_2_weather.mp3
# check start signal again xine sig2.wav
# extract signal part, times in seconds, use wcalc wavcut -if sig2.wav -bt 24000 -et 24480 -of sig2_cut.wav xine sig2_cut.wav
# backup cp sig2_cut.wav sig2_cut.BAK.wav
atpdec sig2_cut.wav xv sig2_cut-1.png
--------------------- using atpdec as decoder on noaa15 and noaa18 sats, waiting for a pass... result:
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Noisy, slim-jim (a piece of TV lint) as indoor sat antenna is not good enough.
Not into a large high 137 MHz antenna atm. There are better weather pictures on geostationary sats, but I think you need a subscription for those, not in hacking mood today.
The slim-jim antenna will work much better when out on the ocean for example, with free view to the horizon.
I use the 'predict' program to find a usable pass: Orbit Calendar For NOAA-15 Date Time El Az Phase LatN LonW Range Orbit -----------------------------------------------------------------
Wed 15Aug18 16:52:58 0 147 236 29 338 3293 5354 * Wed 15Aug18 16:54:36 7 145 240 34 340 2648 5354 * Wed 15Aug18 16:56:13 15 140 245 40 341 2023 5354 * Wed 15Aug18 16:57:48 28 132 249 46 343 1465 5354 * Wed 15Aug18 16:59:15 46 110 252 51 345 1074 5354 * Wed 15Aug18 17:00:25 55 66 255 55 348 956 5354 * q1.gpl # gnuplot q1.gpl
# Only use 44100 samples/s then xpequ fft shows right values
/root/compile/pantel/rtl-sdr/librtlsdr-0.5.3/build/src/rtl_fm -d $device_nr -F 9 -M fm -f 430125000 -p $correction -s 44.1k -r 44.1k -l $squelch | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc 250-4k | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 40 1020-980 | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 60 1290-1220 | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 60 1500-1400 | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 60 1680-1620 | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 60 1880-1820 | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 60 2080-2020 | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 60 2280-2220 | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 60 2480-2420 | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 60 2680-2620 | \ sox -t raw -r 44.1k -e signed-integer -b 16 -c 1 - -t raw - sinc -t 60 2880-2820 | \ /root/compile/pantel/xpequ/xpequ -i - -z 44100 -c 1 -b 16 -o - -s | \ lame -r -s 44.1 --bitwidth 16 -m m - - | \ tee -a /mnt/sda1/video/nbfm_430125000_pi2nos_$serial_number.mp3 | \ mpg123 -
xpequ I wrote, on my site, latest version audio AGC (no more whispering) and spectrum display, equalizer.
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It is interesting that removing significant parts of the middle audio spectrum does not kill intelligibility.
Anyways, so much for a change from squirrels :-)