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Temperature Sensor using 741 OPAMP & LM35

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This project uses IC LM35 as a sensor for detecting accurate centigrade temperature. Linearity defines how well over a range of temperature a sensor’s output consistently changes. Unlike thermistor, Linearity of a precision IC Sensors are very good of 0.5°C accuracy and has wide temperature range. its output voltage is linearly proportional to the Celsius (Centigrade) temperature. The LM35 is rated to operate over a -55° to +150°C temperature range.It draws only 60 µA from its supply, it has very low self-heating, less than 0.1°C in still air. LM35 Operates from 4 to 30 volts. Output of IC is 10mv/degree centigrade for eg if the output of sensor is 280 mV then temperature is 28 degree C. so by using a Digital multimeter we can easily calculate the degree temperature. For trigger point you should set the voltage of pin 2 of IC 741 by using preset or potentiometer. Our aim of this project is not to construct a thermometer but to activate or deactivate a device at a particular m...
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Small stereo amplifier project for computer

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If you want will build a Small stereo amplifier project for computer. This projects is best for you. Before read detail of they we should read mono model on This is Super Small Power Amplifier BCL 1.2W by TDA7052. If you are seeking the circuit amplifies small-sized. I begs for to advise this circuit because tiny economize with the equipment is a little. This is Super Small Power Amplifier BCL 1.2W by TDA7052. If you are seeking the circuit amplifies small-sized. I begs for to advise this circuit because tiny economize with the equipment is a little. And still can use force against large-sized get comfortablely ( I has tried already ) besides it still use volt power supply very wide be about 1.5V arrive at 15V as well. Regard as IC TDA7052 be worthwhile very much. For you who want to try build this circuit. I has model PCB give a friend tests to see with. Request have fun the circuit amplifies miniature please.
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How to interface the stepper motor

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       This project is an extension to two-phase  Unipolar Stepper motor interfacing with AT89C51 using IC L293D .  In the previous project, transistor switches were used to interface the stepper motor with the microcontroller.         Stepper motor is a variable reluctance DC motor.  When correct input sequence of signal is given to  the motor, it starts rotation in steps.  (For more detail refer Unipolar Stepper motor interfacing with microcontroller AT89C51). Note: Stepper motor is a DC motor in which the rotor is made to rotate in steps of x- degrees, where x depends on the type of excitation. In this example we would be considering a simple unipolar stepper motor.   The conceptual model of the unipolar stepper motor is as shown below                  
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Fastest Finger First Mini Project using 8051 Microcontoller

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The quiz buzzer systems are widely used in school, colleges and TV programs. The team which presses the buzzer earliest is entitled to give the answer. At times it becomes very difficult to identify which team has pressed the button when two teams press the buzzer within a very small time gap. In such cases the decision can be biased due to human intervention. The quiz buzzer presented here takes care of the aforesaid problem. This quiz buzzer disables the other inputs as soon as the first buzzer is pressed. This quiz buzzer can be used for a maximum of eight teams. It is build around 8051 microcontroller (AT89C51).
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Custom Character Display in 16X2 LCD

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The commonly used 16x2  LCD  can also display custom made characters besides numbers, alphabets & special characters. Any character can be made to appear on a 5x8 pixel matrix element without knowledge of its ASCII value. The idea explained here demonstrates the principle and operation of a simple LCD custom character display using 8051 microcontroller  (AT89C51 ).
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Multiple 7 Segment LED display interfacing

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Many electronic devices use two or more than two seven segment displays to display their output. The two seven segment displays can be connected in two ways. One way is to connect the two displays to the two ports of the microcontroller. However this is not a good way, as this will block all the ports and we cannot use microcontroller for any other purpose. To overcome this problem, we use multiplexing of seven segment display. In multiplexing we use the concept of persistence of vision i.e., human brain cannot differentiate between two events occurring at a time difference of less than .04 sec. In this case the two digits are displayed one after the other so fast that the human brain cannot detect the difference. Although only one digit is displayed at a time it appears as a two digit number. The circuit presented here demonstrates the above principle in form of a counter which counts from 0 to 99 with a small delay. Schematic diagram for interfacing multiple 7 segment ...
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Alarm Clock without RTC using AT89C52

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     This clock works in 12 hour mode and is configured by programming the microcontroller  AT89C52 .  The program uses a delay function for producing a delay of 1 second.      On reset, the LCD prompts the user to set time. Only the hour and minute components can be set by pressing the corresponding switches, repeatedly. These switches are made active low and so they provide ground to the corresponding input pins of the controller. The AM/PM mode is set by toggling the switch between ground and Vcc. Ground would set the clock in AM mode while Vcc would set it in PM mode. The clock starts when start pin is connected to Vcc by pressing the switch.        The set time is displayed on LCD screen and changes as the time passes on. Seconds are increased after every one second by making use of delay function. As second reaches 59, minute is incremented by one and second is reset to 0. Similarly, as minute reache...
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