An acoustic hailing device (AHD) is a specialized loudspeaker that produces sound at high power for communicating at a distance. AHDs vary in design, output, and usability.
An acoustic hailing device (AHD) is a specialized loudspeaker that produces sound at high power for communicating at a distance. AHDs vary in design, output, and usability. (en)
An acoustic hailing device (AHD) is a specialized loudspeaker that produces sound at high power for communicating at a distance. AHDs vary in design, output, and usability. (en)