4 switch combination Combination Lock
This circuit is very basic to build. To open a lock which is connected to the K1 Load, you must press each momentary switch in the correct sequence. The sequenc...
Proximity Alarm
Inverters U1a and U1b are connected in a simple RC oscillator circuit. The frequency is determined by the values of R1, C1 C2 and the internal characteristics o...
Infrared Alarm
This circuits consist of two parts, the first part will transmit a signal, and the second part will detect that signal and trigger a relay.To adjust the circuit...
Password Based Door Locking
Security is a prime concern in our day-today life. Everyone wants to be as much secure as possible. An access control for doors forms a vital link in a security...
RFID Based Security System with AT89S52
This project aimed to develop a wireless system to detect and allow only the authorized persons. The system was based on Radio Frequency Identification (RFID) t...
Home Security System with microcontroller
Security is a prime concern in our day-today life. Everyone wants to be as much secure as possible. An access control for doors forms a vital link in a security...
FingerPrint Security circuit
Personal Safes are revolutionary locking storage cases that open with just the touch of your finger. These products are designed as secure storage for medicatio...
Ringing Phone Light Flasher
I have received several emails asking how to connect up some lights so that when the phone rings, they flash. This is very useful in a situation were there is l...
laser gun, detector unit and control pad
The hardware for this project had three main components: laser gun assembly, detector unit, control pad. The detector units function was to simply detect a lase...
Doorknob touch alarm
The project was originally intended as a present for my brothers dorm room, but a bad capacitor and the lack of a proper oscilloscope caused delays. It has not ...
Mains Remote Alarm
Beeper and/or LED remotely-operated via mains supply line. Pressing the pushbutton of the transmitter, a sound and/or light alert is activated in the receiver. ...
Fridge Alarm with 4060
This circuit, enclosed into a small box, is placed in the fridge near the lamp (if any) or the opening. With the door closed the interior of the fridge is in th...
warbler siren
This circuit provides a good siren noise suitable for warding off robot-predators! Change the pitch by adjusting R2, and R5....
Siren
An electronic siren made from discrete components. The sound produced imitates the rise and fall of an American police siren. When first switched on the 10u cap...
Doorbell light for the Deaf
This circuit provides a delayed visual indication when a door bell switch is pressed. In addition, a DPDT switch can be moved from within the house which will l...
Doorbell light for the Deaf
This circuit provides a delayed visual indication when a door bell switch is pressed. In addition, a DPDT switch can be moved from within the house which will l...
Intruder Alarm
This is a simple single-zone burglar alarm circuit. Its features include automatic Exit and Entry delays and a timed Bell/Siren Cut-Off. It`s easy to use. First...
Motorcycle Alarm II
This circuit features an intermittent siren output and automatic reset. It can be operated manually using a key-switch or a hidden switch; but it can also be wi...
Motion-detection Digital Camera circuit
When the sensor detects movement in a room it will take a burst of 10 photos with the digital camera. Each photo is taken at 0.5sec interval. After the 10 photo...
alarm using PIC16F628-04
This article describes a 2-Input alarm developed on the PIC LICK-1 Module using a Microchip PIC16F628-04. The program uses the internal 4MHz oscillator and if ...