Seeing noise blips go across the screen...the 6700 sees everything!

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I am seeing noise and signals that I have never seen before! As I watch the panadapter, periodically I see pulses of various sizes and shapes cruise across the screen accompanied by clicks, grunts, and other sounds. Many of the blips travel too fast to identify.

It would be neat if there were a capture button and if I were fast enough to press it, to capture and save the noise blips for later analysis. I guess this really is a moot point since once I capture it I would not know how to analyze it...

Just musing....
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  • es-static

Posted 7 years ago

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You've probably heard these signals for years, but are seeing them now. They have different names, whistlers, birdies...I've even heard them called radio "sprites". They are most often thought to be generated by the atmosphere, or storms, and always move up the band, like someone tuning across the frequency. They are not just someone spinning the dial while keyed down, as the signals will continue up the band, well past the amateur radio band edges. Set your panadaptor display on it's widest setting and just watch how far you can track them. Here is a far better explanation:
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Dave - WB5NHL

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I see exactly the same thing. I agree. It would be neat to know where they come from. They have no impact on operation just a curiosity.

However, this comment is a symptom of the SDR disease. Now that we see an entire spectrum at a low level we become much more sensitive to the local RFI environment!
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Ken - NM9P

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I remember seeing a flex post linked to a video that said one source of a traveling blip was an iono-sonde transmitter at a university in Austin, TX that shoots a sweeping RF beam into the atmosphere in order to measure the ionospheric height and and MUF, etc. On one video, you could see the first moving hump from the direct path, and a second moving hump following it which was reflected off of the ionosphere. Pretty cool!
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Graham - KE9H, Employee

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Some of those are vertical chirped radars looking at ionospheric layers, called ionosondes.

Some of those are modern replacements for the "Woodpecker" over the horizon radars, that don't interfere with narrow band communications, like the "woodpeckers" did.

For further reading:

Articles in QST by Eric Nichols, KL7AJ
such as:
HF Ionospheric Propagation, QST_2010_DEC

--- Graham / KE9H