Musical Water Shower

Won’t it be nice to have music playing in the background all the while when you take a shower? This simple circuit does the same. It plays different tunes repeatedly for...

TRAFFIC BATON

In small towns, there are no traffic lights and the police regulates the traffic with hand signals. Since their hand signals may not be visible at night, it is necessary to...

TRAFFIC CONTROLLER

This simple traffic controller can be used to teach children rudiments of traffic rules. The circuit (shown in Fig. 1) uses readily available components. It mainly comprises rectifier diodes (1N4001), a 5V...

Hot-Water-Ready Alarm

Electric kettles turn off automatically when water has boiled. What if the boiler beeps to alert you when your water has boiled? The tripping sound of the thermal switch may not...

Peak Hour Timer

Electrical appliances like refrigerators and air-conditioners consume heavy current if the line voltage drops during the peak hours between 6 pm and 9 pm. If there is no low-voltage cut-off in...

Touch Alarm

This is a new type of touch alarm that uses an RF oscillator at its input. One special feature of this touch alarm is that it can use a big-size touch...

Heat Control Unit

This circuit will turn the heater ‘on’ when the temperature of water falls below the lower limit set by you and turn it ‘off’ when the temperature increases above the higher...

Electronic Heart

With this electronic heart glowing on and off, you are sure to steal the heart of that special someone. The circuit uses an NE555 timer wired in astable multivibrator mode. Its...

CAR ANTI-THEFT GUARD

Here is an easy-to-build car anti-theft guard. The circuit, shown in Fig. 1, is simple and easy to understand. When key-operated switch S2 of the car is turned on, 12V DC...

GLOW PLUG CONTROLLER

In diesel engines, the air in the cylinders is not hot enough to ignite the fuel under cold conditions. Therefore each cylinder of these engines is fitted with an electric heater...