A buzzer or beeper is a signalling device, usually electronic, typically used in automobiles, household appliances such as a microwave oven, or game shows.

It most commonly consists of a number of switches or sensors connected to a control unit that determines if and which button was pushed or a preset time has lapsed, and usually illuminates a light on the appropriate button or control panel, and sounds a warning in the form of a continuous or intermittent buzzing or beeping sound. Initially this device was based on an electromechanical system which was identical to an electric bell without the metal gong (which makes the ringing noise). Often these units were anchored to a wall or ceiling and used the ceiling or wall as a sounding board. Another implementation with some AC-connected devices was to implement a circuit to make the AC current into a noise loud enough to drive a loudspeaker and hook this circuit up to a cheap 8-ohm speaker. Nowadays, it is more popular to use a ceramic-based piezoelectric sounder like a Sonalert which makes a high-pitched tone. Usually these were hooked up to “driver” circuits which varied the pitch of the sound or pulsed the sound on and off.

In game shows it is also known as a “lockout system,” because when one person signals (“buzzes in”), all others are locked out from signalling. Several game shows have large buzzer buttons which are identified as “plungers”.

The word “buzzer” comes from the rasping noise that buzzers made when they were electromechanical devices, operated from stepped-down AC line voltage at 50 or 60 cycles. Other sounds commonly used to indicate that a button has been pressed are a ring or a beep. Some systems, such as the one used on Jeopardy!, make no noise at all, instead using light.

1. buzzer’s function buzzer is one kind
of integrated structure electronic news Chinese percussion instrument, uses the DC voltage power

supply, widely applies in the computer, the printer, the duplicator, the alarm apparatus, the

electronic toy, automobile electronic products and so on electronic installation, telephone,

timer makes the sound production component.

2. buzzer’s classified buzzer mainly divides into the piezoelectricity type buzzer and the

electromagnetic buzzer two types.

3. buzzer’s circuit pattern mark buzzer “H” or “HA” (old

standard uses “FM” in the electric circuit with the letter, “LB”, “JD” and so on) to

express.
(two) buzzer’s structure principle the 1. piezoelectricity type

buzzer piezoelectricity type buzzer mainly by the multivibrator, the piezoelectricity buzzing

piece, the impedance matching unit and the acoustical resonator, the outer covering and so on is

composed. In some piezoelectricity type buzzer outer covering is also loaded with the light

emitter diode.
multivibrator by transistor or integrated circuit constitution. After putting through the

power source, (1.5~15V d C operation voltage), the multivibrator starting of oscillation,

outputs 1.5~2.5kHZ the tonic train signaling, the impedance matching unit promotes the

piezoelectricity buzzing piece sound production.
piezoelectricity buzzing piece is made by the zirconium titanic acid lead or the niobium

magnesium sour lead piezoelectric ceramics material. Cover the silver electrode in potsherd both

sides, after polarization and aged processing, again sticks with the 2. electromagnetic

buzzer electromagnetic buzzer by the oscillator, the magnet coil, the magnet, vibrates the

diaphragm and the outer covering and so on is composed.
after connection power source, the oscillator produces the tonic train signaling electric

current through the magnet coil, causes the magnet coil to produce the magnetic field. Vibrates

the diaphragm in the magnet coil and under the magnet interaction, periodically vibration sound

production.

Buzzer’s manufacture

(1) prepares electro-magnet M: Circles 100 on long the approximately 6 centimeter hard bolts

the wire, the terminal leaves behind 5 centimeters to make the lead wire, sticks with the

transparent adhesive plaster the coil, in order to avoid the coil loosens, uses the adhesive

plaster to stick again it on a box, the electro-magnet completed.

(2) prepares shrapnel P: Cuts the next strip width from the hard canned food box the

approximately 2 centimeter long iron sheets, has the right angle curved, meets an electro-magnet

lead wire on the shrapnel, uses the adhesive plaster to cling again the shrapnel on the plank.

(3) makes contact Q with the paper clip, with the book the paper clip barrier height, glues

with the adhesive plaster, draws out a wire, like the chart connects the good electric circuit.

(4) adjusts between M and the P distance (through moves box), enables the electro-magnet to

attract the shrapnel, between the adjustment electronic contact and the shrapnel distance,

enables them to contact exactly, after the circular telegram, may hear buzzing sound.