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Author Topic: 5 kHz bursts, 9 times per 10s, all over HF, deviating ±5 kHz around center freq  (Read 1244 times)

Offline Alain4S

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1.  Frequency (kHz)

No specific frequency. I've noticed those signals poping up, here and there, in about every HF band, dispersed both on amateur and broadcast bands.

2.  Time (UTC)

Any time of the day.

3.  Duration

The broadcasts last for very long, several minutes to several hours.

4.  Receiver Mode

AM and/or SB

5.  Receiver Location

South of Montreal, Canada

6.  Description.

The signal consists of 5 kHz wide bursts of what seems to me white noise. They are centered on a frequency (for instance, 11866 kHz) and deviate ± 5Khz, making this mode 10 kHz wide.

Audio sample : https://whyp.it/tracks/37510/audio-sample?token=1ZP4t

« Last Edit: August 19, 2022, 1347 UTC by Alain4S »

Offline Alain4S

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I had hoped that this forum would be frequented by useful people who know about these signals.

Offline Shortwave_Listener

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The picture looks like it might be local QRM (interference) to me. The audio recording link goes to a 404 error so I can’t hear what it sounds like.
Lucas Bandura
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Songs are identified with Shazam if needed. I usually use KiwiSDR receivers. Reception from my QTH is using an SDRPlay RSP1A for SWL with a 40 meter band Inverted V at 40 feet. Kenwood TS-570D for ham use.
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Offline Charlie_Dont_Surf

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Yes, likely interference generated near by you.

I say that because 1) no one else is reporting this and 2) broad signals that appear in random places often are unintended electromagnetic interference from computers or perhaps from power inverters, battery chargers, some motor control circuits. It's hard to point to an exact source at this time.
I don't STRETCH the truth.

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Every minute Charlie squats in the bush, his signal gets stronger."

Offline redhat

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Another clue is that it occurs day and night.  Signals propagating from afar will not behave in such ways, especially across the HF spectrum.

Somewhere under the stars...
Airspy HF+, MLA-30/Mini-whip/Chi-Town Loop
Please send QSL's and reception reports to xfmshortwave [at] proton [d0t] me


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