Unknown mess of a signal 6831khz

[mbstone99]

Does anyone have any idea what this mess is? I was band-scanning on the U of Twente WebSDR tonight and came across this data signal/feedback loop. Whatever it is for me at least has been like this as well for the last hour.

Matt

 

[vagrant]

Probably some encrypted data stream. Hmmm…Google results offer U.S. Navy and or NATO use.

 

[jimmy9999]

It looks like a STANAG signal

 

[mbstone99]

It looks like a STANAG signal

Unfortunately I didn't get a recording of it but I did notice that it sounds like a STANAG with the way it cycles up when it restarts the data stream every 10 minutes or so just with a lot more feedback.

Matt

 

[Token]

Does anyone have any idea what this mess is? I was band-scanning on the U of Twente WebSDR tonight and came across this data signal/feedback loop. Whatever it is for me at least has been like this as well for the last hour.

Matt

This is feedback. It happens occasionally, and there is lots of speculation exactly what causes it, but I suspect several different things may cause it. It has been noted from various sources, including US, Russian, French, etc. Sometimes it appears on known military frequencies or networks (such as your case, this frequency is known to be used by the US Navy, out of Peurto Rico), and other times it appears on random freqs. Sometimes you hear the normal traffic for the network in question mixed with the feedback, other times you hear random things mixed with the feedback, and still others, only the feedback.

Occasionally you hear someone argue this is data or some encrypted mode, but that idea falls apart under analysis. However, since a thought, once published on the internet, never goes away, that suggestion is still pretty common.

Many years ago it was given the nickname "Whales", "Backwards Music", and received the ENIGMA noise ID, "XM". If you search for examples under those names you should find something close to your sound. Since this is almost certainly an accidental signal, there is a good bit of variation in how they sound.

Below are a few examples of XM / Whales / Backwards music from my own YouTube channel:

Oddity station Whales, Backwards Music, or ENGIMA ID XM, 5768 kHz, LSB mode, 16 April,2021, 1902 UTC
Oddity station, XM Whales / Backwards Music, 4457 kHz USB, September 7, 2014, 0426 UTC

T!

 

[vagrant]

@Token - Now that you point it out it is easy to hear/realize the feedback. I figured it was some unknown data mode and probably encrypted due to the uniqueness both audibly and visually on the waterfall. Not that I can recognize all data modes, but I had not heard the OP audio before. Thanks

 

[mbstone99]

This is feedback. It happens occasionally, and there is lots of speculation exactly what causes it, but I suspect several different things may cause it. It has been noted from various sources, including US, Russian, French, etc. Sometimes it appears on known military frequencies or networks (such as your case, this frequency is known to be used by the US Navy, out of Peurto Rico), and other times it appears on random freqs. Sometimes you hear the normal traffic for the network in question mixed with the feedback, other times you hear random things mixed with the feedback, and still others, only the feedback.

Occasionally you hear someone argue this is data or some encrypted mode, but that idea falls apart under analysis. However, since a thought, once published on the internet, never goes away, that suggestion is still pretty common.

Many years ago it was given the nickname "Whales", "Backwards Music", and received the ENIGMA noise ID, "XM". If you search for examples under those names you should find something close to your sound. Since this is almost certainly an accidental signal, there is a good bit of variation in how they sound.

Below are a few examples of XM / Whales / Backwards music from my own YouTube channel:

Oddity station Whales, Backwards Music, or ENGIMA ID XM, 5768 kHz, LSB mode, 16 April,2021, 1902 UTC
Oddity station, XM Whales / Backwards Music, 4457 kHz USB, September 7, 2014, 0426 UTC

T!

Oh I read about Whales and heard samples of it but never live on the radio. But yes that does sound similar to what XM Whales sounds like. Hmm interesting info about the feedback. Thanks!

Matt

 

[a417]

@Token - Now that you point it out it is easy to hear/realize the feedback

It just clicked for me, as well. Almost a Homer moment once I read @Token 's post.

 

[Token]

@Token - Now that you point it out it is easy to hear/realize the feedback. I figured it was some unknown data mode and probably encrypted due to the uniqueness both audibly and visually on the waterfall. Not that I can recognize all data modes, but I had not heard the OP audio before. Thanks

My reply: "Occasionally you hear someone argue this is data or some encrypted mode, but that idea falls apart under analysis. However, since a thought, once published on the internet, never goes away, that suggestion is still pretty common" was not aimed at your post. More than once I have had people insist, sometimes to the point of anger in the exchange, that this is data. Their argument is (sometimes) that it is encrypted and masked so that you cannot tell it is data. And occasionally they point to some web resource that claims it is data (most often very old, unless it is repeating / rehashing some old reference), to strengthen their argument.

T!

 

[vagrant]

I did not perceive you were addressing me in particular, but rather sharing your insight which I and a417 appreciate. My guess was not based on something previously read nor heard. An open mind, to some degree, has helped me along the way. Although, girlfriends might disagree.