Rain Alarm

GIVES BEEP WHEN WATER IS IN CONTACT WITH THE WIRE Rain Alarm Project Here is an interesting electronics project to detect if there is raining or not. Same circuit can also be used as water level indicator or as a tank overflow indicator. Working: Water is a conductor of electricity. Read more…

Musical Bell

This circuits uses very few component and gives melody sound. It uses 3 terminal IC UM66 and can be build small enough to be placed inside a greeting card and operated off a single 3V flat button cell. There is not much to the circuit. The UM66 is connected to Read more…

Heat Sensor

Here is a simple circuit which can be used as a heat sensor. In the following circuit diagram thermistor and 10K Ohms resistance is connected in series and makes a potential divider circuit . If thermistor is of N.T.C (Negative temperature Coefficient ) type then after heating the thermistor its Read more…

Four Tone Siren

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. Read more…