Powernumpty

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Powernumpty
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  • 30 min disconnection!?!?

    @mdfrc99

    Wow.
    Thank you for illustrating the whole generational stereotype.
    Very funny, made my morning.

    OK here is the real answer:
    These radios are things people have bought themselves, a few hundred dollars of investment initially, then add, buying and putting up antennas, sorting out noise issues even changing what we do around the house to help the radio perform well. Then we share them for people who are interested, want to listen to radio in another location, or who themselves cannot set up such a radio, we don’t get anything back for that other than thinking that perhaps someone has benefited a little.

    If the location is good, and the radio set up well then the limited number of slots is soon used up, it’s not like a streaming radio where numbers are almost unlimited it’s just a few users at any one time and each one takes up a chunk of our internet bandwidth. The way to allow everyone to get a little for testing is to limit connection time, 30 minutes is pretty extreme but you must be looking at a very popular Kiwi (mine is set at eight hours).

    If you come to KiwiSDR with the wrong assumptions it does seem strange, if you realise these are real people trying to help each other for “good will” alone it may make sense, these are not streaming radio services. You may be able to find a less popular Kiwi that also picks up what you are looking to record they may have no time limit or a much longer one than 30 minutes.
    Bjarnerz3dvpjohnk5mo
  • SuperSDR

  • Trying to understand this noise

    Do the slow waterfall refresh thing. If you have a PC/MAC run the slow waterfall on that, set it up to show the noise best on the waterfall, leave it running as long as you can, while you walk around or stress equipment, E.G. run a heavy graphical render on a PC, CPU stress test, .

    Part of the reason I haven't been on here for ages is that I got fairly obsessed with tracking noise down, got the general level low (fibre lines through the house, CAT7 where it made a noticeable difference) lots of grounding, ferrites and careful cable routing, only to then have any one of my neighbours negate the gains, instantly with a Chinese battery charger or bad PC PSU. I should have changed my username to Sisyphus.

    The first step is really to characterise the noise and look for changes during the day. If you can locate it quickly that is great, (walk round with an AM battery radio) but if you at least know it changes on light level, temperature, people being awake in the house, TV on, then that narrows it down. All wires in the house are antennas, those DC lines from power supplies need to be coiled up, and ferrite clipped. I reduced my GPS lead pickup by using a short GPS antenna and a car type repeater from the roof.

    If you have a mobile browser running with a waterfall, keep moving around poking and changing things until nothing makes a difference anymore. Even before you locate the particular problem, I bet you'll find one or more background source to reduce.

    If you have a cable tracer, the type that uses an audio tone, remind yourself of the noise, then go locking for that pickup, or radiation, on any wiring.

    smg
  • Trying to understand this noise

    Ok, sorry, now I've listened to the WAV it sounds like SMPS.

    I had a neighbour with a 1200W computer supply that would put that across the entire HF, he had a noisy supply but would then put that gaming PC in a glass fronted case with extra long white DC lines for appearances.

    For ruling out sources in your own home, I used to start a very slow waterfall plot on one RX channel, and another more normal speed. Then go round turning things off/on seeing if that changed anything. Make changes at set times so it is easier to identify trends in the slow plot.

    The slow plot can help identify things like "Car A pulls up, one minute later noise starts", "house lights opposite go out, noise disappears", "Garage light off, noise reduces".

    Obviously if you have any sort of null on your antenna you can use that to narrow down the direction but that sounds like switch mode. Other things to test are CAT7 cables, and rerouting the GPS antenna, in case there is any pickup on the shields. Little clip on ferrites on the switcher supplies for everything normally helps general noise floor.

    smg
  • Many connections from 199.7.185.10

    tower-research.com

    "Quantitative Trading and Investment Strategies"

    Thanks for the IP.

    rz3dvp
  • Automatic Link Establishment - MIL-STD-188-141a (ALE 2G) decoding extension

    Audacity can also be set to record over a set threshold.

    Preferences - Sound Activated Recording.

    WA2ZKD
  • Replace FPGA? [success!]

  • BBAI Cannot connect via web browser after build - A little help needed

    Just for info jks (ZL) is about 11hr's ahead of us so response is more likely in his normal daylight hours. (nearly midnight there right now). Also wroth checking this forum early in the morning UK time.

    Thanks for the i2cdetect output, looks similar to what I saw when mine was on last evening.

    Gibsonmb
  • How do I discover my serial number when the hand written one on the PCB is illegible?

    At a guess I'd say 4084, as the first and last look the same the range to try is limited ;-)

    2082, 5085 etc.

    From the original PCB image the serial seems to be same way up as the silk screen.

    73

    Stu

    PeterB_VK2OP
  • Backups via USB SD Card Reader?

    FYI. There are micro SD card extenders, that would be a quick way to avoid opening the case.

    I know, not a clever answer ;-)

    KU4BY