Any ideas as to what I might be picking up on SDR? They make for some strange patterns. Picked them up at the following coordinates: (31.514596, 74.345092) using GQRX, tuned to 217.25 MHz. As for the second snapshot, I'm not sure what the exact frequency was but it was close to 217.25 MHz.
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3$\begingroup$ Can you provide your location, your setup, frequency and time axes on your plots, and spectrogram parameters? $\endgroup$ – Juancho Jun 12 '17 at 12:09
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1$\begingroup$ Hello and welcome to ham.stackexchange.com! Please consider taking the tour to get the most from the site. $\endgroup$ – Mike Waters♦ Jun 12 '17 at 12:33
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$\begingroup$ Do the side tones disappear quicker than the centre tone if you reduce gain? Might be clipping or intermodulation! $\endgroup$ – Marcus Müller Jun 12 '17 at 12:36
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$\begingroup$ What's the relationship between the first and second pictures, if any? $\endgroup$ – Phil Frost - W8II Jun 12 '17 at 13:28
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2$\begingroup$ The first signal is almost certainly just noise from some electronics, possibly the receiver itself. Notice how it doesn't change over time: this means it contains no information. $\endgroup$ – Phil Frost - W8II Jun 13 '17 at 11:46
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"it might be European television broadcasting. What is your location?"
From the spectrum, it's neither video or DAB.
Looks like a spurious or other radiation from a nearby source.
Frank
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According to https://fccid.io/frequency-explorer.php?lower=217.2&upper= it might be European television broadcasting. What is your location?