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New (to me) QRM

Today I notice a new type of QRM, on/off data type about 19 seconds cycle with varying power.
The screen dump is from the RSP1A and Wellbrook loop HDSDR simply because the Kiwi and LZ1AQ loop is angled and tweaked over time to reduce the pickup from next door so does not show it so well (still really obvious and audible but looks like just noise. Anyone seen this before?
I thing VDSL is higher in frequency but it does look like some data retrying to connect.



  • I have noted odd signals just below 10 MHz here and determined it was an intruder, didn't look like yours however
  • jksjks
    edited September 2018
    I was sure we had a VDSL RFI discussion topic someplace, but I can't find it. Anyway, 8.5 - 12 MHz is a classic VDSL RFI symptom. The pulsing might be a nearby VDSL modem in "re-train" mode trying to figure out the line equalization or something. See here:


  • Thanks for that, the VDSL did seem a good candidate due to the cycle but I could not find the thread just before giving up and going to bed. That spectrum ties up nicely.
    A neighbour reviews stuff on YouTube so I will have to look at his channel see if other than four screens endless gaming kit and 7 wifi access points he has now added a router with a hanging cable.
    I would laugh but I doubt I'd hear myself.

    Could be someone has gone away for a few days and rather than turn the router off they just pulled the plug and left it hanging.
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