This is asimple siren sound that high power output and very noisy. ICs, Digital ICs are easy to use number CD4046 Inverter circuit and four transistor power increase current out to horn speaker 20 watt 4ohm – 8ohm.
How This Circuit works
Operation of the circuit when the circuit is connected to power. Frequency generator circuit starts, the cycle will be the second frequency generator set to a first set of IC1 / 1, R2, C2 generator frequency 1Hz.Output can be modulated. With integrated suite 2, which is R3, R4, C3, ZD1 the modulation and frequency of Set 2 is the origin of IC1 / 2, R5, C4 are the output out of pin 12 of IC1 / 2 to Pin 1 of IC1 / 3.The output from the pin 2 is connected to IC1 / 4, IC1 / 5 and pin B of the Q1 output of IC1 / 4, IC1 / 5 is connected to pin B of Q2. we can observe that Q1 and Q2 will run switch. Well, if work makes Q1 Q4, Q5 run a current through the speakers and will work if Q2 Q3, Q6 running a current flowing through the speakers. The nature of the circuit of Q3-Q6 will result in high currents flowing through the speakers, the sound of the siren is very loud. [...]
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