[cgabios]

Try this at home (and only at home), on a signal generator:

EAS combined tone (TV) 853 Hz sine-wave + 960 Hz sine-wave ("+" means simply combine both waves together, neither modulation nor any other fancy convolutions)

EAS single tone (AM radio) 1050 hz sine-wave

For iOS, http://sgenerator.scorpionzzz.com/en/index.html is a full-featured signal generator.