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szpajder / dumpvdl2

VDL Mode 2 message decoder and protocol analyzer
GNU General Public License v3.0
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No decoded data. #17

Closed thebaldgeek closed 3 years ago

thebaldgeek commented 3 years ago

vdlm2dec and acarsdec both work Ok (thousands of messages per day) so I am confident that the antenna and RTLSDRv3 dongle are working correctly.

Built on a Pi 3 with the lite OS version. Did an apt-get update and apt-get upgrade before starting the build. No other ADSB etc software installed. Just 1 USB SDR dongle installed.

I carefully followed the instructions on the github page:

  1. git clone git://git.osmocom.org/rtl-sdr.git
  2. cd rtl-sdr/
  3. mkdir build
  4. cd build
  5. cmake ../
  6. make
  7. sudo make install
  8. sudo ldconfig
  9. sudo apt install build-essential cmake git libglib2.0-dev pkg-config
  10. sudo echo "blacklist dvb_usb_rtl28xxu" >> /etc/modprobe.d/blacklist.conf`
  11. Rebooted the Pi.
  12. git clone https://github.com/szpajder/libacars
  13. cd libacars
  14. mkdir build
  15. cd build
  16. cmake -DMIRISDR=FALSE -DSDRPLAY=FALSE -DSOAPYSDR=FALSE -DSQLITE=FALSE -DETSY_STATSD=FALSE -DRAW_BINARY_FORMAT=FALSE -DZMQ=FALSE ../
  17. make
  18. sudo make install
  19. dumpvdl2 --rtlsdr -0 --gain 42 --correction 7 136.725 136.775 136.800 136.975

dumpvdl2 2.1.0 (libacars 2.1.3) Sampling rate set to 1050000 sps Found 1 device(s): 0: Realtek, RTL2838UHIDIR, SN: 00000001

Using device 0: Generic RTL2832U OEM Found Rafael Micro R820T tuner Exact sample rate is: 1050000.026077 Hz [R82XX] PLL not locked! [R82XX] PLL not locked! Center frequency set to 136 Hz [R82XX] PLL not locked! Device #0: gain set to 42.10 dB Device 0 started Allocating 15 zero-copy buffers

After running for 2+ hours, there is no output. With vdlm2dec I see output within 15-20 seconds during the day. I prefer the decoded text output rather than JSON and have dumpvdl2 running Ok from 2-3 years ago, just the newer version is not showing any output.

Thanks for your help.

szpajder commented 3 years ago
  1. git clone https://github.com/szpajder/libacars
  2. cd libacars
  3. mkdir build
  4. cd build
  5. cmake -DMIRISDR=FALSE -DSDRPLAY=FALSE -DSOAPYSDR=FALSE -DSQLITE=FALSE -DETSY_STATSD=FALSE -DRAW_BINARY_FORMAT=FALSE -DZMQ=FALSE ../
  6. make
  7. sudo make install

So you have built and installed libacars (giving it plenty of -D options which it does not care about, since they all apply to dumpvdl2 rather than libacars), but have you actually built dumpvdl2?

  1. dumpvdl2 --rtlsdr -0 --gain 42 --correction 7 136.725 136.775 136.800 136.975

dumpvdl2 2.1.0 (libacars 2.1.3)

OK, it shows version 2.1.0, so let's assume that you've built it at some point. But this is not how you pass channel frequencies to it. Check out the help text:

common options:

[ [...]] VDL2 channel frequencies, *in Hz*
thebaldgeek commented 3 years ago

I am an idiot. I need to carefully and fully RTFM Thank-you Frequency in Hz and getting output.