UM3561 alarm systems circuit
This alarm systems circuit is designed using the UM3561 integrated circuit which can be used in various alarm systems using few electronic parts.
This UM3561 alarm systems circuit project require few electronic parts and is powered from a simple 3 volts dc power supply.
T1 transistor enables supply to the sound generator IC when the base current starts following trough it .
When the two points A and B are unconnected the alarm circuit is activated and sound will be provided to the speaker.
Sound that will be hear when alarm is active can be selected using some jumper that must be connected between pin 1 and 6 .