A megaphone, speaking-trumpet, bullhorn, blowhorn, or loudhailer is usually a portable or hand-held, cone-shaped acoustic horn used to amplify a person’s voice or other sounds and direct it in a given direction. The sound is introduced into the narrow end of the megaphone, by holding it up to the face and speaking into it, and the sound waves radiate out the wide end. A megaphone increases the volume of sound by increasing the acoustic impedance seen by the vocal cords, matching the impedance of the vocal cords to the air, so that more sound power is radiated. It also serves to direct the sound waves in the direction the horn is pointing. It somewhat distorts the sound of the voice because the frequency response of the megaphone is greater at higher sound frequencies.
Open the Back Cover by releasing the Latch. Remove the 2 plastic Cell Containers and insert 8 nos. UM-2 Cells with correct polarity as indicated on the CelI Containers. Then place the Cel Containers in the cell compartment maintaining correct polarity as shown on the inside wall of the compartment. Carefully close the Back Cover and lock the Latch. To activate the megaphone, press the Trigger Switch on the Grip. When using the megaphone, place your lips as dlose as possible to the Microphone. Adjust the Volume Control to the desired level without causing any howling or feedback.