Elenco Upgrade Kit SC500 to SC750 - Manual (Page 131)

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Project #PC31
Police Siren Amplifier PC
OBJECTIVE: To show the output of an amplifier.
You may also make different alarm sounds by connecting the alarm
IC using the configurations shown in projects #23-26.
Build the circuit shown and set Winscope to the settings shown
below. The siren sound is very loud. In most cases the waveform
will have flat edges on the top and bottom, indicating the voltage
is too high for the microphone input stage on your computer and is
being distorted. You may sometimes correct for this if you like by
reducing the volume control of your microphone input (see p. 3),
but it is recommended that you return the volume to the normal
level before doing other projects.
Settings
Flat edges
Modify the circuit in PC31 by replacing the alarm IC (U2) with the
music IC (U1). Use the same settings as in PC31 to view the
waveform, you may also use the FFT button to view the frequency
spectrum.
Project #PC32
Music Amplifier PC