Squarewave generator designed for 480Hz output (untested). The circuit uses an NE555

Internal components:

C1 0.1uF capacitor
C2 0.01uF capacitor
R1 10K resistor
R2 10K resistor

External connections:

1 Vout (oscillates 0V - Vin)
2 Not connected
3 GND
4 Not connected
5 Vin (5V-12V)

Here's an example of how you might hook-up the generator

Important: Failure to use a resistor causes the 555 to overheat; a proper tone is not generated.

The frequency of oscillation off the 555 timer is:

f = 1.44/(C1(R1+2R2))

Given C1= 0.1uF, R1=R2=10K produces a theoretical frequency of 480Hz.

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