Traffic Baton
In small towns, there are no traffic lights and the police regulate 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...
Cordless Multi-Door Alarm
Thwart the attempt of burglary by detecting intrusion with this alarm circuit. Each door is protected by a separate circuit built around an independent 555 timer IC in conjunction with reed...
