| Here’s a 555-based project that can be used as mailbox alarm. By suitable mounting of the LED and the phototransistor, the circuit is able t...
More about Alarm (115)
| A digital alarm clock which decodes and synchronises itself to the time signal picked up from the Rugby ‘MSF’ transmitter on 60 kHz.This is...
| This alarm system uses two PIC16F84 processors and is relatively easy to build and install. The cost is very low compared to ready-made syst...
| This time, Velleman have sent us a car burglar alarm construction kit for evaluation. This is a fairly simple but highly functional circuit,...
| Crime in general is still on the rise, and having an alarm system installed is no longer a privilege of the wealthy. This article show...
| The alarm may be used for a variety of applications, such as frost monitor, room temperature monitor, and so on.
| The alarm circuit uses infra-red light beams to bridge distances between 3 m and 5 m (10 ft to 16 ft), but if the transmit diode is give...
| The alarm uses a pyrosensor to detect the presence of animals or human beings by changes in hear radiation.
| Every day a large number of private cars get stolen or broken into. One of the available deterrents against car thieves is a loud car ala...
| These days, if you want to protect your home and valuables, you can't avoid installing a clever and reliable alarm system. The circuit...