Traffic Light Project
Circuit Diagram of Four Tone Siren
Four Tone Siren Project
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 for amplification of audio signal.
This circuit gives sound of Police siren, Ambulance siren, Fire brigade siren and Machine gun sound.