Electric_megaphone Public_address_system

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a woman using small handheld electric megaphone @ demonstration in portugal. electric megaphones use type of horn loudspeaker called reflex or reentrant horn.


in 1960s, electric-amplified version of megaphone, used loudspeaker, amplifier , folded horn, largely replaced basic cone-style megaphone. small handheld, battery-powered electric megaphones used fire , rescue personnel, police, protesters, , people addressing outdoor audiences. many small handheld models, microphone mounted @ end of device, , user holds megaphone in front of her/his mouth use it, , presses trigger turn on amplifier , loudspeaker. larger electric megaphones may have microphone attached cable, enables person speak without having face obscured flared horn.







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