This is an idea for a light detector circuit, using the 555 timer IC. Usually used to produce the frequency (astable multivibrator) much easier.
The only IC with resistors and capacitors aa few, they adjust the frequency to control the unit directly output.Can speakers such as CD ring sounds.The LDR is a resistor to change its value applied lighting.When pin 4 (reset), if the voltage is high this circuit work. R3 with LDR and characterized by a simple comparison circuit voltage.
When the light is very low resistance to the CDS, the voltage at pin 4 is high, the circuit will hear a voice coming out.
The only IC with resistors and capacitors aa few, they adjust the frequency to control the unit directly output.Can speakers such as CD ring sounds.The LDR is a resistor to change its value applied lighting.When pin 4 (reset), if the voltage is high this circuit work. R3 with LDR and characterized by a simple comparison circuit voltage.
When the light is very low resistance to the CDS, the voltage at pin 4 is high, the circuit will hear a voice coming out.
