Alarm and strange sound appear at the same time on shortwave!

[senderjaeger]

The "alarm" noise on 15260 kHz is jamming (some country tries to block a foreign broadcast that it doesn't want to be received by its citizens). The second noise sounds like some kind of digital communication on the 20 m amateur radio band.

[superarticulation]

@senderjaeger Thanks for reply in my channel. I bought a Satellit 750 and listen shortwave everyday. The alarm appears on 7520KHz before UTC 15:00 quite often. As for the 2nd sound, is there some kind of software decrypt it?

[fancysnake1]

it sounds like a weather radio

[MattExzy]

YES. It's the WEIRD ALARM NOISE :O

[SWL1409]

It could be SSTV but I have never hear that noise on 15260kHz.

[superarticulation]

@SWL1409 As for 15260 noise. It came out at any frequence and even 20 years ago I could receive it. 15260 is the highest frequency I found it came out. Usually it appears below 10000KHz, and shows quite far from me.

Regard from China.