Nuts and Volts - November 2010

you connect the piezo speaker leads to the input leads of an oscilloscope and tap on the speaker with your finger, you ought to get a trace very similar to Figure 2.

You could also see voltage change with the application of a temperature change. I do not recommend applying heat to see this voltage change. It is too easy to permanently damage the film. If you are adventurous, try applying heat from a bare incandescent lamp while observing the trace on a high impedance oscilloscope. NV

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REFERENCES

Kawai, H., (1969). Jpn. J. Appl. Phys, 8, 975-976.

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