Very strange noise over the entire HF spectrum...

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  • Updated 5 months ago
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While exploring the HF bands I found today a very strange noise pattern coming from NE direction over the entire HF is peculiar that the noise isn't affecting the amateur radio bands, it's cut off exactly where the bands are. Anyone has seen something like this? Very weird...hard to explain.


Here is the recording:
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Posted 5 months ago

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Photo of Mark - WS7M

Mark - WS7M

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 Maybe a close by solar system?  No idea really just a guess based on the hash sound and the regular on/off cycle.

Was this recorded during daylight?
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It was recorded around 10PM EST....this was active in the morning as well, then stopped. 
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Ken - NM9P, Elmer

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With what looks like the ham bands carefully notched out of the spectrum, it looks like it could be a Broadband-Over-Power-Line (BPL) system.  Are there any located along the bearing you are aiming?

Other options include: 

RV/Boat Shore power inverter/charger. ( My had a neighbor's that wiped me out whenever he hooked it up to charge before his next camping trip, and to top it off when they returned.)

Switching wall mount power supply.  (My under-counter Halogen hockey-puck lights do this whenever my wife turns them on.)

Plasma TV in the neighborhood?
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Rory - N6OIL

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HAARP maybe?
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Tim - W4TME, Customer Experience Manager

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The extraterrestrials have HAARP shut down for maintenance 
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Steven G1XOW

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From the very sharp ham band notching, this is almost certainly a digital comms system such as a PLT device, and its pretty close too. I am not aware of any SMPSU or Solar IV or power transfer system that could notch to that level of precision over such a wide spectrum.