Project #539, Electronic sound project #541, Lighthouse – Elenco Upgrade Kit SC100 to SC750 User Manual
Page 162: Electronic sound (ii) project #540

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Build the circuit and turn on the slide switch (S1), you hear a high-
frequency tone. Press the press switch (S2) to lower the frequency by
increasing the capacitance in the oscillator. Replace the 0.1
μF
capacitor (C2) with the 10
μF capacitor (C3, “+” on the right) to further
lower the frequency of the tone.
Project #539
OBJECTIVE: To make different tones with an oscillator.
Electronic Sound
Project #541
OBJECTIVE: To make a blinking light.
Lighthouse
Build the circuit and turn on the slide switch (S1), the LED (D1) flashes
about once a second.
You can also change the frequency by changing the resistance in the
oscillator. Replace the 100K
Ω resistor (R5) with the 10KΩ resistor
(R4), place the 0.1
μF capacitor (C2) back in the circuit as before.
OBJECTIVE: To make different tones with an oscillator.
Electronic Sound (II)
Project #540
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