Ключевые слова: alarm, alert, amp, amplification, amplifier, announce, announcement, antenna, asia, asian, audio, blue, bright, broadcast, cable, calling, column, communication, disaster, disasterprevention, electric, equipment, forecast, horizontal, information, japan, japanese, loud, loudspeaker, megaphone, metal, new, news, outdoor, pillar, post, power, public, safety, shout, siren, sky, sound, soundsystem, speak, speaker, station, steel, surveillance, system, talk, tell, tower, voice, volume, warning, wire, wireless,