Variable oscillator project #477, Variable oscillator (ii) project #478, Project #479 – Elenco Upgrade Kit SC300 to SC750 User Manual
Page 54: Variable oscillator (iii) project #480, Variable oscillator (iv) project #481, Photo variable resistor, Project #482, Variable whistle chip oscillator project #483, Slow adjusting tone project #484, Slow adjusting tone (ii)
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OBJECTIVE: To change the tone using the adjustable resistor.
Set the adjustable resistor (RV) to the bottom position. Turn on the slide switch (S1) and you
should hear sound from the speaker (SP). Adjust the resistor to hear the different sounds.
Variable Oscillator
Project #477
OBJECTIVE: To change the tone using the adjustable resistor.
Variable Oscillator (II)
Project #478
Project #479
Use the circuit in project #477. Connect the
whistle chip (WC) across points B & C and
adjust the resistor (RV).
Variable Oscillator (III)
Project #480
OBJECTIVE: Show variations of project #477.
Variable Oscillator (IV)
Project #481
OBJECTIVE: Show variations of project #477.
Photo Variable Resistor
Use the circuit in project #477. Connect the whistle chip (WC) across points A & B
and adjust the resistor (RV). You should hear a higher tone. This is generated by the
whistle chip (WC).
Project #482
OBJECTIVE: Show variations of project #477.
Variable Whistle
Chip Oscillator
Project #483
OBJECTIVE: Show variations of project #477.
Slow Adjusting
Tone
Project #484
OBJECTIVE: Show a variation of project #483.
Slow Adjusting
Tone (II)
Use the circuit in project #477. Connect the
whistle chip (WC) across points D & E and
adjust the resistor (RV).
Use the circuit in project #477. Replace the 100k
Ω
resistor (R5) with the photoresistor (RP). Wave your
hand over the resistor and the sound changes.
Adjust the resistor (RV) to make more sounds.
Use the circuit in project #477, remove the
speaker (SP). Make three more sounds by
placing the whistle chip (WC) across points, A
& B, B & C, and D & E.
Use the circuit in project #477. Place the 10
μ
F
capacitor (C3) (+ towards the top) directly over the
.02
μ
F capacitor (C1). A tone is generated once or
twice per second, depending on the resistor setting.
Use the circuit in project #483. Replace the 10
μ
F
capacitor (C3) with the 100
μ
F capacitor (C4) and the
tone is much slower. To make it even slower, replace the
100
μ
F capacitor (C4) with the 470
μ
F capacitor (C5).
OBJECTIVE: Show variations of project #477.