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Could someone help me identify these components? Answered

Hello everyone,
                            I was opening up a pair of  old piezo buzzers and found these inside(attached picture).Dunno what they are nor what they do but when I opened up a relatively new buzzer,I found that this has been replaced by a 470 ohm resistor.The rest of the circuit remains the same which include a few resistors,a BC 547 NPN transistor and a speaker.The observation is that the old buzzer produces a much louder noise than these new ones with the same volts and amps...Given all that,anybody seen 'em before?

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iceng

Best Answer 4 years ago

Both are inductors which are better then resistors in buzz applications.
Resistors limit current flow but turn that excess current to Heat !
That is wasted away.

Inductors limit current by storing it in a magnetic field which is returned
later in a buzz cycle as the magnetic field collapses causing a louder sound,

A

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Adarsh_tronix

4 years ago

So,Will the buzzer produce a louder noise with an inductor of a higher or a lower value?

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icengAdarsh_tronix

Answer 4 years ago

That is very hard to answer without a circuit schematic and the other component values.

Usually the inductor must resonate with the capacitor for the loudness to be at the highest.

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Adarsh_tronix

4 years ago

Thank you everyone,So they are inductors huh?I believe their unit is henry....but any idea about the magnitude of inductance of these inductors ?I need to purchase some to try a buzzer of my own so I require the value.

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icengAdarsh_tronix

Answer 4 years ago

Put  some dimensions or a millimeter scale in a better picture.

In the meantime try 150 uH to 300 uH like this one.

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Adarsh_tronixiceng

Answer 4 years ago

Thanks for the reply.I'll try the suggested inductors and I am working on the picture too.

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Josehf Murchison

4 years ago

Ok they are inductors.
You have RC and LC oscillators.
The buzzer you have has an LC oscillator driver.
A pic of the whole thing would be better.

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benmurton

4 years ago

this is an inductor, the resistors and transistors create the oscillating dc current to make the sound, then the inductor amplifies it. an inductor is just a coil of wire.