Elenco Upgrade Kit SC500 to SC750 - Manual (Page 65)

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Project #646
OBJECTIVE: To build a high pitch oscillator.
High Pitch Oscillator
Project #648
Low Pitch
Oscillator (II)
OBJECTIVE: To modify project #646. OBJECTIVE: To modify project #646.
Project #649
Low Pitch
Oscillator (III)
Replace the 0.1 μ F capacitor (C2) with the 10 μ F capacitor (C3) placing
the “+” sign towards the top. Turn the slide switch (S1) on; now the circuit
oscillates at a lower frequency.
Replace the 10 μ F capacitor (C3) with the 470 μ F capacitor (C5) placing
the “+” sign towards the top. Turn the slide switch (S1) on and the circuit
oscillates at a lower frequency now.
Set the adjustable resistor (RV) to the top position and then turn the
slide switch (S1) on. You hear a high pitch sound and the LED (D1)
flashes at the same rate. Change the oscillator frequency by adjusting
RV.
OBJECTIVE: To modify project #646.
Low Pitch Oscillator
Project #647
Replace the whistle chip (WC) with the 0.1 μ F capacitor (C2). Turn the
slide switch (S1) on and now the circuit oscillates at a lower frequency.