"Sonar Ping", 7631.5kHz

[caylorman]

All,
    I recorded this unusual signal on 7631.5 kHz at 18:58 UTC on 20 March 2020.  The only thing I can describe it as is a sonar ping.  It's a repeating series or short pips that descends in volume like an echo.  Just posting it to see if anyone has heard anything like it before, or could tell me is this is an actual digital signal or just some local QRM.

https://soundcloud.com/e-j-caylor/20-mar-2020-18h58m04sz-76315-mhz-usb/s-cAIIJwanPKb

Caylorman

[Josh]

A weird one for certain, never heard before by me as well.
Radar, sounder, lid playing with an amp pecker or adjusting his bug, who knows.

https://www.qsl.net/ei7ba/Woodpecker.htm
https://www.youtube.com/watch?v=wyzsjqI9-OY

[blw]

That's and interesting one, for sure. Thanks for the audio sample. It's a good audio file.

[Token]

I have heard a very similar signal from a stuck automatic antenna tuner.  Not saying that is what this is, I don't know what it is, but it sounds similar to that stuck tuner.

It is about a 70 msec cycle (~30 msec on, ~40 msec off), or about 14 pulses / sec.

T!