Radio "wave" ?

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Moose

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Forgive me if not the correct forum, but I thought you guys might know what I'm seeing. I recently started using a RTL-SDR device with SDR# software. I'm tuned to a random station on SW and I'm just zoning out looking at the zig-zag noise level running left to right when I see a spike on the left side of the screen. I thought it was a station but the spike traveled left to right like a wave in the ocean. I was in AM mode and I didn't hear anything when it crossed my frequency. I've only seen this happen twice in the last several months. Thanks
 

ka3jjz

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It would be much more helpful if you would supply a time (in UTC, preferably) and frequency. A screenshot of your display would also help identify what you are seeing

Mike
 

aggie72

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I've seen this before. Several years ago I had my spectrum analyzer hooked up to my shortwave antenna. While watching the amplitude of the broadcasting stations there was this small blip that ran completely through the screen. I kept moving the center point of the SA to watch the blip for a few minutes as it kept moving for many Mhz. It finally lost strength until I couldn't see it. I don't recall the frequency band but I did some internet searching at the time and found a few articles about shortwave propagation testing that may be related.
 

ridgescan

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A guy here whose handle is Token once explained this thing but I cannot find it and cannot recall the jist of it. I think he said it's something that is some sort of band propagation checker for some unknown entity.
I'm off to search further for this.
I found this in the University of Twente site about this.

http://websdr.ewi.utwente.nl:8901/chirps/article/

I see the same thing on my spectrum scope but I actually hear the "chirp" as it passes over the frequency I'm on. I suspect the reason you didn't hear that chirp like you said, is you might have had an Auto Notch Filter engaged.
 
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majoco

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I often hear and see 'sweepers' going right through the HF spectrum but it's not one of them, they'e much too fast. Another thing I see on my WinRad G33DDC is a 'hump' of noise that slowly travels across the screen from either direction, sometime a bit unstable and have a distinct warble if I'm set to SSB as it passes through the selected frequency. In the end I tracked it down to a birdie from a laptop - I guess there's many of them at various harmonics - every laptop that I have does the same. It's not a biggie, the "hump" is probably only about 10dB more than the background noise.
 

majoco

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OK, here's a pic of a hump...as you can see, it's just noise and it cover about 200kHz, it's slowly moving left to right and takes about 2 minutes to go from one side to the other, so it's moving about 250kHz per minute. You can see in the waterfall it's just a fuzzy line with a couple of jitters in it but that's only showing about 20seconds.
 

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Fletch

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I've seen this a lot

Anyone know what this might be? (In the red circle, a little hard to see)? It looks like a a pulse type transmission going across the entire spectrum. Kind'a like what was described previously. I captured this from the Netherlands web radio radio receiver.
 

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