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Thread: ICAO code allocation ranges

  1. #11
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    Receiver as pictured. Running dump1090 on macOS.

    I have hundreds of verified correct hits over many days, and for those listed I have multiple hits over successive minutes and then they are not seen again. It seems to me (as a developer and IT professional) that the decoder and software are behaving consistently and the bad data, if that's what it is, is being transmitted that way.

    IMG_0413.jpg

  2. #12
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    Quote Originally Posted by zkarj View Post
    Running dump1090 on macOS.

    I have hundreds of verified correct hits over many days, and for those listed I have multiple hits over successive minutes and then they are not seen again. It seems to me (as a developer and IT professional) that the decoder and software are behaving consistently and the bad data, if that's what it is, is being transmitted that way.
    It's very unlikely anything like that is transmitted. Much more likely that it is a repeated 1-bit decoding error that doesn't get corrected or filtered. I have seen it many times when CRC checking gets turned off by mistake, or too aggressive mode is used for signal detection.

    Post your dump config.

    /M
    F-ESDF1, F-ESGG1, F-ESGP1, F-ESNK1, F-ESNV2, F-ESNV3 F-ESSL4, F-LFMN3
    P-ESGR, P-ESIA, P-ESIB, P-ESGF

  3. #13
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    I'm running it with the following command (lat & lon dumbed down for public consumption):

    ./dump1090 --interactive --net --lat -41.000000 --lon 174.000000 --modeac --mlat --write-json /usr/local/var/dump1090-mut-data

  4. #14
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    Shouldn't need modeac, and I'm surprised it's going with interactive. That changes the output to screen priority and not data out relay..

    Sent from my XT1092 using Tapatalk
    Posts not to be taken as official support representation - Just a helpful uploader who tinkers

  5. #15
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    I've taken out the modeac, but leaving off interactive makes it spew copious amounts of unreadable (due to speed) output, which I suppose I could pipe to /dev/null. but it seems like more work than just the live readout. Running interactive it's got plenty of headroom on the CPU using only about 15% of one core out of four.

  6. #16
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    Like I said, you are not doing any CRC correction. Add --fix , and I think that will remove the faulty decodes.

    /M
    F-ESDF1, F-ESGG1, F-ESGP1, F-ESNK1, F-ESNV2, F-ESNV3 F-ESSL4, F-LFMN3
    P-ESGR, P-ESIA, P-ESIB, P-ESGF

  7. #17
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    Thanks, I've added that in. I'm going through now and purging all of the known dodgy codes (quite a few more had shown up since my original post and were similarly out-of-range of any allocations). I'll see if anything new shows up. I noticed that all of them had shown up on only one occasion each, which is certainly possible for ordinary aircraft (especially non-locals) but does lend weight to the spuriousness of them. I also have 260 minutes' observation of 000000 but that seems like it might be a different thing.

    I'll post back here after a while if anything has (or hasn't) cropped up with --fix in operation. Meanwhile, I have a bunch more codes to research in case they're real. We had a Royal Jordanian G650 over the other day – one of only two aircraft I've captured in the 4xxxxx range. It's amazing what comes into this little place on the bottom of the world.

  8. #18
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    Two more have appeared:

    5d849c between 2018/01/15 23:26 - 23:30
    44d310 between 2018/01/17 05:44 - 05:48

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