Analysis of information sources in references of the Wikipedia article "Specific Area Message Encoding" in English language version.
Note: Severe thunderstorm and Tornado warnings are also accompanied by a 1050 Hz warning tone to trigger basic tone alert receivers.
The FCC specifies that the message portion may be audio, video, or text. In practice, neither text nor video is actually embedded into the audio signal. Video and text accompany video broadcasts of EAS alert audio, but these elements are not part of the audio encoding of EAS, and are not propagated through the "daisy chain" architecture of EAS decoding receivers.
Note: Severe thunderstorm and Tornado warnings are also accompanied by a 1050 Hz warning tone to trigger basic tone alert receivers.
The FCC specifies that the message portion may be audio, video, or text. In practice, neither text nor video is actually embedded into the audio signal. Video and text accompany video broadcasts of EAS alert audio, but these elements are not part of the audio encoding of EAS, and are not propagated through the "daisy chain" architecture of EAS decoding receivers.