1 . Piezo Buzzer : piezoelectric buzzer multivibrator, piezoelectric buzzer, impedance matching and resonance box, shell, etc.. Some piezoelectric buzzer housing is also equipped with light-emitting diodes. Multivibrator constituted by transistors or integrated circuits. (1.5V-15V DC operating voltage) when the power is turned on , themultivibrator start-up , output 1.5-2.5kHZ audio signals, impedance matching is to promote the piezoelectric buzzer sound. The piezoelectric buzzer piece is lead zirconate titanate or lead magnesium niobate piezoelectric ceramic material . Plated on both sides of the ceramic sheet on the silver electrode, the polarization and the aging treatment, and then glued together with the sheet brass or stainless steel sheet. 2 . Electromagnetic buzzer : the electromagnetic buzzer by the oscillator, the electromagnetic coil, magnet, diaphragm and housing. After power on, the audio signal generated by the oscillator current through the electromagnetic coil, the electromagnetic coil generates a magnetic field. The diaphragm in the electromagnetic coil and the interaction of the magnet, periodically vibrating sound.
8 x 5 x 2,
"Ships in 24 hours": Processing Time is guaranteed to be shorter than 24 hours.
os correios perderam minha encomenda, mais a MiniInTheBox mandou novamente todos pedidos, e logo depois os correios acharam a outra que estava perdida e mandou novamente eu nem sei o procedimento de devolução. Empresa Eficiente Honesta.