Well, HF is a garden of endless sound varieties.
Now, what's this? Something out of order?
Recorded on 6990 USB, wide filter setinng, at approx. 2109 UTC, S5-S7 signal strength.
A decent portable receiver and simple antenna allows everybody to discover the sounds, noises and mysteries of the Airwaves. Believe me: there is still life on Shortwave! And many, many mysteries...