This circuit is a wireless car alarm system that is built using two circuit modules, namely modules of transmitter and receiver modules. This circuit works on FM radio waves. Car alarms can be used on vehicles that have a 6-12VDC power supply. You can use the voltage stabilizer if your car power supply is too… Read More »
This is a car alarm simulator which using the LED as a simulation output. This simple circuit can tell you whether your car is running or not by detecting the voltage difference when the car is on and off. This occurs because when your car is running the Alternator puts a out a voltage a… Read More »
Here the circuit diagram of safer security system alarm. There are many security systems use a closed loop of wires and switches arranged so that whenever a door or window is opened, the loop will be broken and the alarm will sound. An obvious problem is that someone can tamper with the system, short out… Read More »
Here is the circuit diagram of simple multitone alarm. This is a low cost circuit which is simple and easy to build. The main components of this circuit is based on dual op-amp MC1458 and LM 380. The two op amps inside the MC 1458 are used to produce square and triangular waves. LM 380… Read More »
This is door knob touch alarm for your home security purpose. The alarm will be activated when someone touch the metal door knob. This circuit won’t work on full metal door.