This is a low cost, simple, yet a surprisingly powerful electronic siren powered by just a 9V battery. The circuit may provide the final circuit […]
Tag: alarm circuit
Heat Detector + Siren
This is the diagram of heat detector circuit which already integrated with siren circuit in the output. This circuit applies a complementary pair comprising NPN […]
Safer Security System Alarm
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 […]
Simple Fire Alarm with Thermistor and NE555
The following circuit is a simple fire alarm circuit based NE555 timer and use thermistor as a temperature detector. This sensor will activate the transistor […]
DIY Simple Multitone Alarm
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 […]
Door Knob Touch Alarm
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 […]