Wind Sound Generator

Wind Sound Generator

Using this simple circuit, one can generate the sound of wind. The circuit is basically an astable multivibrator build around two NPN transistors.
By adjusting the 1M potentiometer (VR1), the sound can be changed from that of wind to storm, sound of sea, hiss of escaping gas from a container through a small hole etc. A 9-Volt or 6-volt unregulated power supply is enough. How-ever, a battery may be used instead. The output sound will be slightly changed. The prototype has been successful tested with the given power supply. Also and 8-ohm, 5cm, low wattage speaker is recommended.

PARTS LIST
Resistors (all ¼-watt, ± 5% Carbon unless stated otherwise)
R1 = 1 MΩ
R2 = 4.7 KΩ
R3 = 100 KΩ
R4 = 10 Ω
VR1 = 1 MΩ
Capacitors
C1 = 0.01 µF
C2 = 0.0033 µF
C3 = 1000 µF/16V
Semiconductors
T1, T2 = BC548
D1 = 1N4001
Miscellaneous
X1 = 230V AC Primary To 9V/6V – 0V AC Secondary
LS1 = 8Ω speaker