This morning I came across a strange pattern noise or sound on the MW band.
The radio wave must have been strong as even my YAESU VX-8D amateur radio could be received. Now China and Taiwan broadcast on 1206kHz near my country. In short, I might have received either Radio Taiwan International or Yanbian People's Broadcasting Station.
A legend radio Sony ICF-2010(ICF-2001D) and Sangean ATS-909X can also be received. This is not an internal spurious noise.
I recorded the sound, here.
The strange noise is such as short repeated sound generated by scratches of the CD. This broadcasting station may not manage their owned CDs properly. Intentionally or unintentionally, the scratched CD sound must have been on the air as a result.
The noise or sound has been continued more than 30min. At 5:30 JST(at 20:30 UTC, October 7th) the noise or sound has been faded out then new musics with clear sound has started instead.
Although I doubt the medium wave a Chinese or a North Korean pirate radio for the first time I heard, at last I found the medium wave Yanbian People's Broadcasting Station spoken to Korean language.
That was an interesting broadcasting accident.