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Project #pc21 buzzing in the dark pc – Elenco Computer Inteface for Snap Circuits® User Manual

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Project #PC21

Buzzing in the Dark PC

OBJECTIVE: To build a circuit that buzzes.

Build the circuit shown. If continuing from the previous experiment
then close the Winscope program and run it again, to reset the
settings. Set Winscope to the settings shown below and click on
the On-Line button to activate. A sample waveform is shown here.

The actual waveform will vary depending on how much light is
shining on the photoresistor (snap part RP). If you cover the
photoresistor then the circuit shuts off.

Settings

The waveform above is weak and
erratic, so replace the 0.02mF
capacitor (snap part C1) with the
0.1mF capacitor. A sample of the
new waveform is at left, with the
same settings. It is lower in
frequency but higher in amplitude.