Download PK-101 REV

EXPERIMENT #35: ELECTRONIC NOISEMAKER
Connect the circuit, connecting the battery last since it will turn the circuit on. Press the switch several times quickly. Then
turn the variable resistor knob to change the frequency of the sounds.
Do you understand what’s happening when you press the switch? You increase the oscillator capacitance by putting the
0.005µF in parallel with the 0.047µF, and this lowers the oscillator frequency.
As usual you can experiment with changing component values if you like.
.005µF
+9V
502
S
33kΩ
P
473
470Ω
51