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Four Tone Siren - Electronics Project and Circuit
Circuit Diagram of Four Tone Siren UM3561 Project Picture UM3561 IC includes oscillator and selector circuits so few external component is used for construction of four tone siren. The UM3561 contains programmed mask ROM to simulate siren sound. Power consumption of IC is low. It is powered by 3 Volt. One NPN Transistor is used …