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Thread: FT8 QRM....

  1. #1
    The Fluid of Spock KD8TUT's Avatar
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    FT8 QRM....

    Hi guys,

    I was working some Olivia around 14.073 and kept seeing weird spiked signals pulse up into the narrow bandpass I had setup for a 500hz filter. Kept looking at it more deeply... and it seems to be a really sophisticated attempt to QRM FT8.

    Essentially a tone is transmitting every 60hz or so from just below the FT8 segment to just above. It does severely interfere with decoding if the signal is strong enough.

    I've seen it on 20 and 40 meters now. Initially it seemed to me that it was a really mucked up transmitter. Don't think that's the case. I would not have noticed it except it shows up 1khz below and above the FT8 segment.

    On the bright side the tones didn't derail my Olivia QSO.

    Another case of FT8QRM is really funny:

    Some station had the voice capability enabled in JTAlert to call out frequencies and call signs observed. He was blasting that voice out across the segment when transmitting. Got a laugh out of that...

    Hope you are eating well today!!
    --
    So there I was, totally naked. With only a rubber hose and a stuffed animal...

  2. #2
    Forum Addict WZ7U's Avatar
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    I guess jammers come in all stripes...
    Signature void - please reinsert credentials or call tech support

  3. #3
    Administrator N8YX's Avatar
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    Bearings on the jammer(s)?
    "Everyone wants to be an AM Gangsta until it's time to start doing AM Gangsta shit."

  4. #4
    The Fluid of Spock KD8TUT's Avatar
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    Quote Originally Posted by N8YX View Post
    Bearings on the jammer(s)?
    I don't have a directional antenna.
    --
    So there I was, totally naked. With only a rubber hose and a stuffed animal...

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