(one) buzzer's introduction
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 <dnt> </dnt> <dnt> the </dnt>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         

The speaker divides into the built-in speaker and outside sets at the speaker, but outside sets

at the sound box which the speaker namely refers to generally. The built-in speaker is refers to

the MP4 player to have the built-in loudspeaker, such user not only may also be possible to

listen to the sound which through the telephone jack through the built-in speaker the MP4 player

sends out. Has the built-in speaker's MP4 player, may not use the external connection sound box,

might also avoid the long time matching inconvenient which the belt earphone brought.
    speaker commonly used parameter physics significance:
   speaker's parameter is refers to uses the speaker concrete each performance parameter value

which the special-purpose speaker test system tests. Its commonly used
parameter mainly includes: Z, Fo, η0, below
SPL, Qts, Qms, Qes, Vas, Mms, Cms, Sd, BL, Xmax, Gap gauss. respectively is these kind of

parameter its physics significance.
   1.1 Z: Refers to speaker's resistance value, including: Rated impedance and direct-current

impedance. (unit: Ohm /ohm), usually refers to the rated impedance.
  speaker's rated impedance Z: Namely for the impedance curve first maximum value's behind

smallest impedance mold value, the resistance value which namely Figure 1 center point B      

it is calculates the speaker electric power the datum.
   direct-current impedance DCR: Is refers to the voice coil coil static situation, passes

directs current the signal, but tests resistance value.
   we usually called 4 ohms or 8 ohms refer to the rated impedance.
  1.2 Fo (lowest resonance frequency) is refers to the speaker impedance curve first maximum

value correspondence the frequency.
  unit: Hertz (Hz).
Speaker's impedance diagram of curves is the speaker under the regular service conditon, obtains

the speaker impedance mold value with the constant flow law or the constant pressure law along

with frequency
change curve.
  1.3 η0 (speaker's efficiency): Is refers to speaker output accoustical power rate and the

input electric power ratio.
  1.4 SPL (acoustic pressure level): Is refers to the loudspeaker when passes by the rated

impedance 1W electric power voltage, in the reference axis with the loudspeaker is distanced 1m

the sound pressure which lights
to produce. Unit: Decibel (dB).
  1.5 Qts: Speaker's total quality factor value.
  1.6 Qms: Speaker's mechanical quality factor value.
  1.7 Qes: Speaker's electricity quality factor value.
  1.8 Vas (loudspeaker's dischargeable capacity): Is refers to closes tightly air acoustic

compliance and the speaker unit's acoustic compliance is equal when the rigid vessel the <dnt>  

 volume. Unit: Rises (L).
  1.9 Mms (vibration quality): Is refers to the speaker to participation in the rate process

vibrates various parts' quality sum total, including drum paper part, voice coil, bullet wave by

  and participation vibration air quality and so on. Unit: Gram (gram).
  1.10 Cms (strength along): Is refers to the speaker vibrating system's support part's mild-

manneredness. Its value is bigger, speaker's entire vibrating system is softer. List
    position: Millimeter/Newton (mm/N).
  1.11 Sd (vibration area): Is refers to speaker's vibration process, drum paper/membrane

effective vibration area. Unit: Square meter (m2).
  1.12 BL (magnetic force): Gap magnetic induction intensity and effective sound loop line long

product. Unit: (T*M).
  1.13 Xmax: Voice coil in vibration process movement linear traveling schedule. Unit:

Millimeter (mm).
  1.14 Gap Gauss: Gap magnetic induction intensity value. Unit: Tesla (Tesla).
 may know the principle nearly same difference by above is the former vibrates the latter with

the reed is directly the coil is shaking a paper cone frequency to request low one to request

the high-tech the former simpler the latter multiple structure in turn

Maintains beloved earphone's 10 to suggest 

     After an earphone succeeds in obtaining, we first are must praise the earphone, does the reason believed that I did not say everybody will also know. After praising, we might enjoy, but was so long as praised on is well with everything? The answer whether, some earphone's quality does go through a strategic pass very much, is because we usually do not add in the use carefully only then cause our beloved earphone premature die young! Below repairs the situation which on me in the earphone process often saw, for everybody some maintenance suggestion!
    1, should better not when sleeping matches the belt earphone. Average person impossible night of motionless, the time, the ear equipment and lines were not steadily absolutely the winding on the neck are twisting which two line bread twists resembled likely in the same place, some big earphone outer covering is even crushed. at the beginning of the 100th, 200 crossbeams is also the quite frail place! If some friends said that I do not listen to the song I not to be able to fall asleep, then should better be hangs the earphone, is above yours head, ties up the ear equipment and lines with a rubber band to hang in the head. Falls asleep, as soon as will tilt the head the earphone quilt “to pull” gets down, regardless of your turning over will not press! Is plays the cushion with the rubber band advantage in the anchor ear machine-hour the role!
    2, uses the earphone, must and so on wipe off the ear equipment and lines on sweat. These human bodies secrete the thing, includes fat anything, causes <dnt> the </dnt> wire rod stealth murderer, for instance e2c in ear knee bend place. The time has been long, the wire rod will get older, finally will cause the slot, the break.
   3, in uses time the earphone should better not smoke. Everybody has is not careful, regardless of being the earphone outer covering, the ear equipment and lines has burnt, hundred and thousand of oceans you can not love dearly??? Moreover the cigarette ash will enter to the earphone outer covering in sticks in shakes on the membrane, the time long sound has not been right.
    4, use, certain pass small volume. If your output unit's volume is oversized, not only shakes the ear, light shakes the membrane fold. Heavy earphone's voice coil overburning.
    5, the earphone are far away from the strong magnetism. Unit magnet magnetism will drop, gradually the sensitivity will drop!
    6, the earphone are far away moistly. In the earphone unit welds at the plate meeting to rust, the resistance increases, your earphone can the leaning sound.
    7, connector flange. Some friends like mp3 anything placing in the pants pocket, the plug going beyond a line part very easy booklet, the time long to have been able the broken line.

   8、, do not disassemble. The curiosity has been too strong, opens has a look. Some earphones are very difficult to disassemble, mx500 does not use the special method is cannot make, was you opens 80% to be also bad. Perhaps small 2 open spoils the outer covering, or presents the leaning sound, 888 and 808 such alright, are quite fond of playing jokes.
   9, the winter should better not use in outside. The winter is cold, the wire rod is quite hard, crisply, the excessive knee bend is very easy to break off the wire rod. By now do not to the ear equipment and lines heating, the high temperature accelerate the wire rod the aging.
   10, is far away from chemistry goods. The earphone outer covering coats with lacquer dissolves very much in the organic chemistry material, mishandles flowers has been unattractive.
     this was the platitudes thing, said nothing but is hopes everybody's earphone to be able the multipurpose years!