Electronics projects

Circuit diagram: Line Follower Robot Circuit Principle: This circuit consists of ATmega8 microcontroller, two IR sensors, motors and motor driver IC. The line follower robot needs mechanical arrangement of the chassis. Assume a two wheel robotic vehicle with a castor wheel. The two IR sensors are mounted on the robot facing towards Earth. When robot is placed on the fixed path, it follows the path by detecting the line. The robot direction of motion depends on the two sensors outputs. When the two sensors are on the line of path, robot moves forward. If the left sensor moves away from the line, robot moves towards right. Similarly, if right sensor moves away from the path, robot moves towards its left. Whenever robot moves away from its path it is detected by the IR sensor. IR sensor consists of IR transmitter and IR receiver on a board. When the vehicle is moving on a black line, IR rays are continuously absorbed by the black surface and there is no reflected ray makin

Circuit diagram: Line Follower Robot Circuit Principle: This circuit consists of ATmega8 microcontroller, two IR sensors, motors and motor driver IC. The line follower robot needs mechanical arrangement of the chassis. Assume a two wheel robotic vehicle with a castor wheel. The two IR sensors are mounted on the robot facing towards Earth. When robot is placed on the fixed path, it follows the path by detecting the line. The robot direction of motion depends on the two sensors outputs. When the two sensors are on the line of path, robot moves forward. If the left sensor moves away from the line, robot moves towards right. Similarly, if right sensor moves away from the path, robot moves towards its left. Whenever robot moves away from its path it is detected by the IR sensor. IR sensor consists of IR transmitter and IR receiver on a board. When the vehicle is moving on a black line, IR rays are continuously absorbed by the black surface and there is no reflected ray makin

Transmitter: Receiver: Wireless Metal Detector Robot Circuit Principle: The proposed system consists of transmitter and receiver circuit. The transmitter circuit transmits the commands required to operate the robot. The receiver circuit receives these commands through RF and moves the robot according to the received commands. A metal detector is interfaced to the controller in the receiver side. Thus whenever any metal is detected the robot stops there and buzzer starts ringing. Circuit Components: AT89c51 microcontroller. RF encoder and decoder RF transmitter and receiver pair. Push buttons. Buzzer. Robot. L293d Rs 232 cable. Software Components: Keil software Flash magic Proteus. Circuit Design of Metal Detector Robot using Microcontroller: The metal detection robot project can be divided into sections 1) Transmitter section, 2) Receiver section. The transmitter section consists of RF encoder, RF transmitter and Push buttons. RF enc

Circuit Components IC LM358 555 Timer IC Laser light 150 Ohm, 10K Resistor 10 K POT 220uF capacitor LDR Breadboard 9 Volt Battery and Connector LED Working of Laser Security Alarm Circuit In this circuit we have set reference voltages of comparators by using potentiometer, we can say this sensitivity of the circuit. Comparator is configured in non-inverting mode. In this system we have placed laser light and LDR facing each other, so laser light continuously falls on LDR. Due to this a potential difference generated across the non- inverting pin of comparator, then comparator compare this potential difference with reference voltage and generate a digital output as HIGH. Before this we have configured 555 timer in mono- stable mode so we it required a LOW trigger pulse at its trigger pin to activate buzzer and LED. So we applied output of comparator at trigger pin of 555 timer. Even comparator’s output is HIGH when laser lights falls on LDR so at

12v DC to 220v AC converter:- Principle Behind this Circuit:- The basic idea behind every inverter circuit is to produce oscillations using the given DC and apply these oscillations across the primary of the transformer by amplifying the current. This primary voltage is then stepped up to a higher voltage depending upon the number of turns in primary and secondary coils. Also get an idea about 12V to 24V DC Converter Circuit Inverter circuit Using Transistors A 12V DC to 220 V AC converter can also be designed using simple transistors. It can be used to power lamps up to 35W but can be made to drive more powerful loads by adding more MOSFETS. The inverter implemented in this circuit is a square wave inverter and works with devices that do not require pure sine wave AC. Components required:- 12v Battery MOSFET IRF 630 -2 2N2222 Transistors 2.2uf capacitors-2 Resistor 680 ohm-2 12k-2 12v-220v center tapped step up transformer. 2N2222 Datasheet

Components required: Power supply Resistors (1kΩ) Potentiometer (10KΩ) Capacitor (10µF, 16V) BC548 transistor High resistance thermistor (NTC) Diode (1N4001) 6V Buzzer Working of fire alarm circuit Working is based on the switching property of transistor. The thermistor and R1 forms a potential divider network which drives the transistor. The heart of this circuit is a thermistor. Thermistors are low-cost, easily-available temperature sensors widely used for uncomplicated temperature measurements. Thermistors are temperature sensitive resistors. When temperature increases resistance offered by the thermistor decreases and vice versa. At normal temperature, the resistance of the thermistor is around 10kΩ. All resistors vary with temperature, but the semiconductor materials used for thermistors are especially sensitive to temperature. The transistor is turned ON by the voltage drop across the resistor R1. Consider the temperature of the atmosphere is around

Automatic Door Bell Using Object Detection: You can do this by viewing below image & see all components ,connect like this We all have a doorbell at our homes. When a visitor comes to our house, he searches for the doorbell switch and then rings it to let us know his presence. If the who came to our house cannot find the doorbell or else if the person is so short that he cannot reach the doorbell, what can be done? How will it be if we use an automatic doorbell which rings as soon as a person arrives at our place? There are no more hassles. The person who comes to our house need not search for the doorbell and press it any more. If we install this automatic doorbell using object detection circuit, the circuit will automatically sense the presence of the person and it rings the doorbell. When a visitor comes to our house, he searches for the doorbell switch and then rings it to let us know his presence. If the who came to our house cannot find the doorbell or e

Cell phone detector Circuit Components: V1 = 12V L1 = 10uH R1 = 100Ohms C1 = 100nF R2 = 100K R3 = 3K Q1 = BC547 R4 = 200 Ohms R5 = 100 Ohms IC1= LM339 R6 = 10 Ohms LED = Blue LED Detector Circuit Design: The detector circuit consists of an inductor, diode, a capacitor and a resistor.  Here an inductor value of 10uH is chosen. A Schottky diode BAT54 is chosen as the detector diode, which can rectify low frequency AC signal. The filter capacitor chosen in a 100nF ceramic capacitor, used to filter out AC ripples. A load resistor of 100 Ohms is used. Amplifier Circuit Design: Here a simple BJT BC547 is used in common emitter mode. Since the output signal is of low value, the emitter resistor is not required in this case. The collector resistor value is determined by the value of battery voltage, collector emitter voltage and collector current. Now the battery voltage is chosen to be 12 V (since maximum open source collector emitter

Required components: *At89c51 controller *At89c51 programming board. *16×2 LCD *5V Relay *Bc547 (NPN) transistors – 5 *Resistors (1K) – 4 *Resistor – 330 ohm *AC Motor *Pot – 10k *Programming cable *Connecting wires Water Level Controller using 8051 Circuit Design: The main heart of this project is AT89C51 microcontroller. The water level probes are connected to the P3.0, P3.1, P3.2, and P3.3 through the transistors. Port P2 connected to the data pins of LCD and control pins RS, RW and EN of LCD are connected to the P1.0, P1.1, and P1.2 respectively. Initially when tank is empty, LCD will display the message EMPTY and motor runs automatically. When water level reaches to quarter level, now LCD displays QUARTER and still motor runs. For further levels, LCD displays the messages HALF and ¾ FULL. When tank is full, LCD displays FULL and motor automatically stops. Again motor runs when tank is empty. How to Operate Water Level Co