Although this circuit has a few wonderful features, it is quite simple to construct. Controlled by a PIC micro-chip, the features include: 1. A car alarm (connected to the door switch) 2. A hi-jack mode (which will activate if the reset button is not passed, after the door has been opened while the car engine is running) and 3. An immobiliser (which is connected to the ignition coil) When the alarm is activated, the siren will gibe one bleep and the indicators will also flash once (twice when the alarm is switched off). The alarm is also self-activating (activates after two minutes) if you should forget to activate the system.