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Author Topic: FSK signals around 27359 USB 1701 UTC  (Read 1460 times)

Offline circuitmike

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FSK signals around 27359 USB 1701 UTC
« on: November 05, 2022, 1703 UTC »
I'm hearing FSK data bursts on 27359 USB. There are others on 27355 USB as well. WTF? I'm in the US and this is a CB radio frequency - FSK data is generally not allowed. I know sometimes CB channel 23 has some FSK paging signals (I hear them all the time at my QTH) but they're nothing like this.
QTH: Western Massachusetts (FN32rp)
Receiver: KiwiSDR (on-site)
Antenna: Wellbrook ALA-1530LN loop

Offline radiogaga

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Re: FSK signals around 27359 USB 1701 UTC
« Reply #1 on: November 05, 2022, 1721 UTC »
Turn on your USA only filter, that should help.

rgg

Offline circuitmike

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Re: FSK signals around 27359 USB 1701 UTC
« Reply #2 on: November 05, 2022, 1724 UTC »
Oh, right, I completely forgot to do that! You know, the thing I love most about HF Underground is the helpful and friendly users.
QTH: Western Massachusetts (FN32rp)
Receiver: KiwiSDR (on-site)
Antenna: Wellbrook ALA-1530LN loop

Offline Token

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Re: FSK signals around 27359 USB 1701 UTC
« Reply #3 on: November 05, 2022, 1814 UTC »
I'm hearing FSK data bursts on 27359 USB. There are others on 27355 USB as well. WTF? I'm in the US and this is a CB radio frequency - FSK data is generally not allowed. I know sometimes CB channel 23 has some FSK paging signals (I hear them all the time at my QTH) but they're nothing like this.

My old wireless mouse used a CB channel freq.  I don't remember which channel off the top of my head, but it was most definitely an FSK signal.  The signal was very bursty, it only showed up when I was actually moving the mouse.  Also I had a car alarm pager that was around channel 35, and that was also FSK.

T!
T!
Mojave Desert, California USA

Offline circuitmike

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Re: FSK signals around 27359 USB 1701 UTC
« Reply #4 on: November 06, 2022, 0020 UTC »
Interesting idea. Somewhere I have an old wireless keyboard that also worked on 27 MHz. These signals sounded too slow and had too long of a preamble to be keyboard presses, I think. I suspect 45.45 or 50 baud. They also were the same, relatively short, length, which wouldn't be likely to be a mouse.

I tried to make an IQ recording but the signals kept getting weaker and falling into the noise (or the stronger stations, assuming more than one station, were listening at those times).
QTH: Western Massachusetts (FN32rp)
Receiver: KiwiSDR (on-site)
Antenna: Wellbrook ALA-1530LN loop

 

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