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Loggings => HF Mystery Signals => Topic started by: Treehouse SWL on January 07, 2019, 0714 UTC

Title: Constant tones on 6925 USB
Post by: Treehouse SWL on January 07, 2019, 0714 UTC
Around the clock in recent weeks on 6925 kHz USB, I'm getting a long tone that lasts for 20-30 seconds, ends for a second or two, and then resumes.

Anybody know what that might be? It's made hearing weak pirate signals really difficult here.
Title: Re: Constant tones on 6925 USB
Post by: MDK2 on January 07, 2019, 1512 UTC
If you can make a recording, please do so and share it here. I suspect that you're experiencing something local because I've had no such experience here (QTH Denver) but I have other things like a spur from my local AM station on 1390 that's ever present at 6950 (5th harmonic) which can make receiving pirates at that frequency tricky, depending on the time of day.
Title: Re: Constant tones on 6925 USB
Post by: Strange Beacons on January 07, 2019, 1648 UTC
I'm in Seattle. I tuned to 6925 kHz in USB mode (http://strangebeacons.proxy.kiwisdr.com:8073/?f=6925usb) and monitored for about an hour and heard nothing. Possible RFI local to your position?
Title: Re: Constant tones on 6925 USB
Post by: Treehouse SWL on January 08, 2019, 2132 UTC
It could be RF from something local, but the tone seems to have some sort of pattern.

My recording equipment is not fancy (cellphone), but I took a video earlier today; the tone is already going when the video starts; I also included what it sounds like in AM mode, which is a bit less distinguishable: https://youtu.be/wQ1L6Xwu73o
Title: Re: Constant tones on 6925 USB
Post by: Strange Beacons on January 08, 2019, 2234 UTC
Interesting. The tone if very subtle, bu definitely there. I'll keep listening for this myself and will see if I can make a recording, too.