It’s a simple metal detector design that has the quite good characteristics. the principle of operation which one differs from the classic schemes (BFO, transmit-receive known as “two-boxes” metal detector, inductive). The dynamic mode is used to find targets in interference environment. There is known from theory of signal filtration that if signal shape is [...]
This Sensor circuit was designed as an aid in parking the car near the garage wall when backing up. LED D7 illuminates when bumper-wall distance is about 20 cm., D7+D6 illuminate at about 10 cm. and D7+D6+D5 at about 6 cm. In this manner you are alerted when approaching too close to the wall. All [...]
This is a simple fire alarm circuit based on a LDR and lamp pair for sensing the fire. It uses a very simple approach to detecting smoke in the air. The alarm works by sensing the smoke produced during fire.The circuit produces an audible alarm when the fire breaks out with smoke. This probably isn’t [...]
Here’s a alarm clock circuit based on PIC Controlled. Two circuit boards put together a simple PIC based design comprising of two interlinked vero-board cards. The larger of the two circuit boards holds the 5V power regulator, the display processor (a PIC 16F74), the real time clock (Dallas DS1307), 3V backup battery and buzzer. See [...]
Here’s a simple home alarm circuit is for those who are eager to know the concept of home security system. It consists of three 555 timers gets the input from a contact that could be connected to a motion detector or any momentary contact that monitors a certain process. Once the contact is momentarily closed, [...]
This circuit is xenon lamp flash detector. It has a very low standby current requirement yet has very high sensitivity toward the light flashes from a xenon lamp. When connected to a flip/flop it can serve as an on on/off controller. Souce: Xenon Lamp Flash Detector See more: Phototransistor Detector
Circuit is Infrared gate sensor. It’s an infrared gate with two sensors planned to use in the wall in the way behind a door. It can be applied in a toilet to keep track of that someone is inside exceeding a certain amount of time. After that time elapsed, the circuit triggers the digital output [...]
