Digital stop watch
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This document describes a digital stopwatch circuit built around a timer IC and 4-digit counter IC. The circuit uses one IC to generate clock pulses and another IC to count the pulses and display the time on 4 7-segment displays. It has switches to start, stop, and reset the stopwatch. When the start/stop switch is pressed, it either resets the counter to zero to start timing or latches the current count to stop timing and store the time.
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Physics Numerical Problem, Metric Physics, Kinematic Problems Karachi, Federa...
Physics Numerical Problem, Metric Physics, Kinematic Problems Karachi, Federa...Al-Saudia Virtual Academy
Physics numerical solutions, kinematics numericals solutions karachi board, federal board physics, SUVAT problems, metric physics solutions karachi, Physics solved numericals of Karachi board,Numericals of Physics metric (X) Federal Board,Federal Board Class X Physics SSC (9th & 10th),9th class physics numerical,Q1. A car is moving on a straight road at 5 m/s. It is accelerated at 3 m/s. What will be its velocity after 4 seconds?Q.2. A bullet train starts from rest and moves with uniform acceleration of 0.12 m/s2. Find its final velocity and distance covered after 5 minutes?Q.3. A bus is moving with a velocity of 72 km/hr. By applying brakes, a deceleration of 0.4 m/s2 is produced. Find the distance, covered by the bus before it stops?Q.4. What is the acceleration of an object which accelerates along a straight path from rest, and attains a velocity of 20 m/s after covering a distance of 50 m in 5 s?Q.5. a wicket keeper catches a ball moving at 30 m/s.
(a) if he does not move his hand the ball comes to rest in his glove over a distance of 1 cm. What is the average acceleration?(b) If he moves his hand as the ball is caught so that it comes to rest over 10 cm. What is its acceleration?
for complete solutions visit our blog: http://hometuitionsinkarachi.over-blog.comdigital Counter
This document discusses counters, which are digital circuits used for counting pulses. It describes asynchronous and synchronous counters, and different types including up/down counters, decade counters, ring counters, and Johnson counters. Examples of counter applications are given such as in kitchen appliances, washing machines, microwaves, and programmable logic controllers. Counters are used for tasks like time measurement, frequency division, and digital signal generation.
Chapter 1 : SIGNIFICANT FIGURES AND STANDARD FORM
Define the significant figures
Determine the significant figures
Identify the rounding off the significant figures
Calculate the whole number and determine the significant figures.
Identify and evaluate the Standard Form
Perform the conversion of length and volume of liquid .
LINEAR and ANGULAR Measurement
In this ppt according to BE syllabus linear and angular measurement is try to describe.
The instruments of this measurements is described in this ppt.
Basic electrical measuring instruments
This document discusses different types of basic electrical measuring instruments. It describes absolute instruments, like tangent galvanometers, which directly measure electrical quantities without needing calibration. Secondary instruments require calibration against a standard, examples being multimeters, clamp meters, ammeters and voltmeters. Multimeters are described in detail, including their display, selection knob and ports. The document explains how to use a multimeter to measure AC voltage, DC voltage, resistance, current and test continuity. Clamp meters and the working of ammeters and voltmeters are also briefly covered.
Measuring instruments
1. Indicating instruments measure electrical quantities by deflecting a pointer on a calibrated scale. They use a deflection system to produce a force proportional to the measured value, a control system to limit deflection, and a damping system to prevent oscillations.
2. Permanent magnet moving coil (PMMC) instruments have a coil mounted between magnet poles that deflects proportional to current. They are used as ammeters, voltmeters, and galvanometers. As an ammeter, the coil is connected across a low resistance shunt; as a voltmeter, it is connected in series with a high resistance.
3. Moving iron instruments can measure AC using an iron core acted on by a coil
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Implementing a Digital Stopwatch Using Basic Stamp2
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Stopwatch counting measuring style design 2 powerpoint ppt templates.
Stopwatch counting measuring style design 2 powerpoint ppt templates.
Physics Numerical Problem, Metric Physics, Kinematic Problems Karachi, Federa...
Physics Numerical Problem, Metric Physics, Kinematic Problems Karachi, Federa...
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Introduction to Integrated Circuits
CoolJunk is India's fastest growing DIY (do-it-yourself) kits company focused on project-based learning in science, engineering and technology. Having 20,000 users in India, US, Singapore, Middle East and New Zealand, the CoolJunk kits are known for quality, innovation and high production value. CoolJunk has been featured in national and international journals including Wallstreet, Yourstory, Hindu Business Line, NextBigWhat and was tagged as the coolest Indian start-up in IAN Bootcamp-2011.
Automated alarm circuits
This document describes two automated alarm circuits - one that produces a bird-chirping sound and another that produces a British police siren tone. The control unit uses ICs CD4047 and CD4027 to trigger the alarm circuits when a door is opened based on the state of a reed switch. Figure 1 shows the circuit for the bird chirping alarm and Figure 2 shows the circuit for the police siren tone alarm, which can be integrated with the control circuit from Figure 1. The document provides instructions on how to assemble and use the circuits as security alarms.
555 timer ic_tesitngcircuit
This document presents a minor project on designing a 555 timer integrated circuit testing circuit. It discusses the objective to create a basic circuit using active and passive components to test if a 555 timer IC is functioning properly. The circuit diagram and components include a 555 timer IC, resistors, capacitors, LEDs, and a power supply. The circuit operates in astable mode to test the 555 IC by checking if the LEDs blink alternately, indicating the IC is working, or remain off/unchanged, indicating it is faulty.
Led chaser
This circuit uses two ICs, including a 555 timer IC, to create a simple LED chaser. The 555 timer IC is configured as an astable multivibrator to generate pulses that drive a Johnson decade counter IC. The counter IC sequentially lights up the LEDs such that each LED remains on for 1 second before the next one turns on, creating a running light effect. A variable resistor can be adjusted to control the speed of the LED chasing by changing the frequency of the pulses from the 555 timer.
Cspass
This document summarizes the Card Swiping and Password Authentication Security System (CSPASS). The system uses an AT89C52 microcontroller, optocoupler, keys, relay, buzzer, and LCD display. It requires a user to swipe their card which is read by the optocoupler, then enter a password on the key matrix which is authenticated before a relay is activated, granting access. Power is supplied through a transformer, rectifier, and voltage regulator to power the various components.
Digital dice
The circuit functions as a digital dice using a binary counter, logic gates, and LED display. The counter cycles through counts from 0 to 6 to randomly display the six faces of a dice. The logic section uses the outputs of the 3-bit counter and logic gates like NOR, NAND to determine which of the 7 LEDs will light up to display the number. Placing a finger on the touchpad starts the oscillator and random counting to simulate rolling a dice.
Clock timer
This circuit uses signals from an alarm clock to automatically turn on a TV or radio at a preset time. When the clock triggers, it sends a signal to a transistor amplifier and comparator chip. This triggers a monostable multivibrator and SCR, which energizes a relay and powers the appliance. The appliance will remain on until the power is disconnected or fails. The circuit allows automatically turning on appliances based on the time set in a standard alarm clock.
Manual fsr'14
This document contains instructions for several electronics projects using common integrated circuits. It includes summaries of voltage regulator IC 78XX, motor driver IC L293D, and describes how to build a line following robot, automatic street light control system, electronic code lock, and water level indicator. Useful online resources for learning electronics are also provided.
SIMULATION OF AN ELECTRONIC DICE CIRCUIT USING LEDs IN PROTEUS SOFTWARE
The following content consists of the brief details about the topic
INTRODUCTION
CONCEPT OF ASTABLE MULTI VIBRATOR
CONCEPT OF DECADE COUNTER IC4017
CIRCUIT EXPLANATION
CIRCUIT DIAGRAM
VIDEO OF CIRCUIT WORKING
WORKING OF CIRCUIT
INFERENCE
REFERENCE
A SYNOPSIS ON VARIABLE POWER SUPPLY WITH DIGITAL CONTROL
This document is a synopsis for a variable power supply with digital control submitted by four students. It describes a circuit built around regulators, counters, and a timer that provides adjustable and stable positive and negative DC voltages. The circuit steps down AC mains voltage before rectifying and regulating it. A timer and counter are used to sequentially activate presets that set the output voltage level. LEDs indicate the voltage levels, and switches allow resetting the output voltage or turning the power off.
Bayas
This document describes a clap switch circuit that can control devices without physically touching switches. The circuit uses a NE555 timer and CD4017 counter IC. When a clap is detected by a microphone, it triggers the NE555 to produce a clock pulse that makes the CD4017 counter change states. Each state controls an output that can turn on a device. Up to 10 devices can be controlled in this way by clapping once to turn on the first device, clapping again to turn on the second, and so on.
Mini project
This anti-sleep alarm keeps you awake. This circuit keeps you vigilant by sounding intermittent beeps and emitting flashing light so as to remind you that you are not on the bed but driving a vehicle. It works only at night due to the control of a light-dependent resistor (LDR) based switch.
Electronic dice
This document describes an electronic dice circuit that uses a 555 timer IC and 4017 counter IC to randomly cycle through dice number displays on 7 LEDs when a push switch is pressed. The circuit provides clock pulses from the 555 timer to step through the counter outputs, which are combined with diodes to illuminate the LEDs in dice number patterns. Pressing the push switch starts the random cycling through the numbers, simulating the rolling of dice.
Assignment#5
This document discusses various types of flip flops including RS, JK, D, and T flip flops. It provides the theory of sequential circuits and flip flops. It also gives the truth tables and explanations for each type of flip flop. The aim is to verify the truth tables of these flip flops experimentally using logic gates, input switches, and output LEDs. The procedure and result are to check the components, make the circuit connections, provide various input combinations, and note the output to verify the truth tables for each flip flop type.
Dice with 7 segment display
This document describes a digital dice circuit using common integrated circuits. The circuit uses a NE555 timer configured as an astable oscillator to generate a 100Hz clock signal. A CD4026 or CD4033 decade counter/display driver counts the clock pulses and displays the random number on a 7-segment display. Pressing switch S1 simulates throwing the dice by extending the clock signal, while S2 resets the display to 0. The random number displayed falls between 0-6, simulating the values on a dice.
Final report
This document describes a remote control circuit that allows home appliances to be turned on and off using an infrared remote control from up to 10 meters away. The circuit consists of an infrared transmitter based on a 555 timer IC and an infrared receiver module that detects the signal from the remote and uses a CD4017 IC and relay to switch the appliance. The circuit provides a low-cost solution to remotely control appliances like lamps, fans, and radios from televisions and DVD players.
Construction of digital voltmeter by Bapi Kumar Das
The document describes the construction of a digital voltmeter. It discusses 6 main sections: 1) a pulse train generator, 2) control and gating circuitry, 3) a counting section, 4) an analog input/transducer, 5) a latching and display section, and 6) completing the connections between all sections. The pulse train generator and control/gating circuitry work together to start and stop counting pulses based on the input voltage. The counting section then counts these pulses. The analog input converts the measured voltage to a signal. This signal is then latched and displayed on the digital readout.
Termómetro digital de -50 a 150 grados con ICL7107
This digital thermometer measures temperatures from -50 to +150°C with 0.1°C resolution. It uses an ICL7107 analog-to-digital converter chip and an NPN transistor as the temperature sensor. The sensor should be connected with shielded cable and properly grounded to avoid noise interference. The ICL7107 requires +5V and -5V feeding voltages which are generated from voltage regulators. The assembly involves soldering components like resistors, capacitors, and regulators before installing the ICL7107 chip due to its sensitivity to static electricity. The thermometer is calibrated by adjusting potentiometers while measuring ice water and boiling water.
Water level controller
This document describes a microcontroller-based water-level controller and motor protector circuit that monitors the water level in an overhead tank and controls a pump motor accordingly. It uses an AT89C51 microcontroller along with sensors to detect the water level and turn the motor on or off to fill the tank. It also protects the motor from high/low voltages, power fluctuations, and dry running conditions using voltage monitoring circuitry. The circuit displays the system status and any faults on an LCD module. It is powered by a 12V supply from a step-down transformer and regulated to 5V for the microcontroller components.
Automatic street light controller
This document describes an automatic street light controller circuit using an LDR (light dependent resistor) and 555 timer IC. The circuit works by using an LDR to sense light levels - when it gets dark, the LDR's resistance increases and triggers the 555 timer to turn on an LED, representing a street light. During the day when light falls on the LDR, its resistance decreases and the LED turns off. The circuit provides automatic light control without manual operation and can be used for applications like street lights that need to turn on at night.
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SIMULATION OF AN ELECTRONIC DICE CIRCUIT USING LEDs IN PROTEUS SOFTWARE
SIMULATION OF AN ELECTRONIC DICE CIRCUIT USING LEDs IN PROTEUS SOFTWARE
A SYNOPSIS ON VARIABLE POWER SUPPLY WITH DIGITAL CONTROL
A SYNOPSIS ON VARIABLE POWER SUPPLY WITH DIGITAL CONTROL
Construction of digital voltmeter by Bapi Kumar Das
Construction of digital voltmeter by Bapi Kumar Das
Termómetro digital de -50 a 150 grados con ICL7107
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Friendly charger for mobile phones
1) The circuit described provides a friendly charger for mobile phones that regulates voltage and current at around 5.6V and 180mA respectively to slowly charge batteries and extend their life.
2) It incorporates over-current protection and a 10 second delay after power is applied to prevent voltage spikes and protect the phone.
3) An op-amp, transistors, resistors, capacitors and zener diodes are used to regulate voltage and current, provide short-circuit protection, and indicate charging and fault status with LEDs.
Flying saucer
This document describes the circuit design for an electronic toy modeled after a flying saucer. It has three sections: a rim flasher circuit using LEDs around the edge that flash sequentially, a dome flasher circuit with LED groups that flash at different rates, and a sound generator circuit. The circuits are built on separate PCBs and mounted in plastic bowls covered with a transparent dome to create the visual effect of a flying saucer when powered on.
Flashing cum running light
This circuit generates flashing running lights using LEDs. It uses a decade counter and two astable multivibrators. The decade counter outputs activate the LEDs one by one. An astable multivibrator produces an 8.4Hz clock signal that switches the LED supply on and off, causing each LED to blink at that rate as the output shifts to the next LED every 1.3 seconds, creating a running light effect. The circuit can be built on a general-purpose PCB and works with a 12V regulated power supply.
Flashing beacon
This document describes a flashing beacon circuit that uses the LM317T regulator IC. The circuit uses a 12V DC power supply, LM317T regulator IC, 12V 10W bulb, resistors, and capacitors. The bulb flashes approximately 4 times per second as the capacitors charge and discharge. The LM317T can deliver over 1 amp of current to power the bulb. A heat sink is included to dissipate heat from the IC. Minor adjustments to the resistor and capacitor values can alter the flashing rate.
Fire alarm using thermistor
This document describes a fire alarm circuit that uses a thermistor as a heat sensor. When the thermistor's resistance decreases due to increased temperature, it provides a low-resistance path that extends positive voltage to trigger an oscillator circuit. The oscillator uses a NE555 timer IC to drive a transistor and sound an alarm through a loudspeaker. The circuit operates off a 6V-12V regulated power supply and can be easily constructed on a general-purpose PCB.
Electronic watchdog
This circuit comprises an infrared (IR) transmitter unit and receiver unit that are mounted on opposite gate pillars. When the IR beam between the units is interrupted, a melody is triggered to sound for 30 seconds from the receiver unit to alert someone that someone is at the gate. The transmitter unit uses a 38kHz IR LED and timer to transmit the IR beam. The receiver unit uses an IR sensor and timer connected to a melody generator IC to detect the beam interruption and play the melody. The units are powered separately but connected to allow the receiver to trigger when the beam is blocked.
Electronic security system
This electronic security system can monitor and alarm for multiple zones like doors and windows. It uses a monitoring circuit and closed loop sensors on each zone. When a sensor detects its zone is opened, it triggers the alarm circuit which sounds an audible alarm. The alarm continues until the triggered sensor is closed again and the reset switch is pressed. The system can monitor additional zones by expanding the monitoring circuit. It operates on battery power, making it portable for various installation locations like homes and businesses.
Electronic horn
This circuit diagram shows an electronic horn that uses an LM3900 integrated circuit with four op-amps. Op-amp A1 generates a low-frequency square wave, op-amp A2 works as an integrator, and op-amp A3 works as a comparator to generate a wandering voltage along with op-amp A2. This wandering voltage modulates the frequency of a transistor and transformer voltage-controlled oscillator circuit comprising op-amp A4, transistor T2, and transformer X1, which produces the sound. The circuit can produce different tones by connecting the wandering voltage to different pins of the LM3900 and can be used as a car horn with a 10W audio amplifier.
Electronic bicycle lock
This document describes an electronic bicycle lock circuit that provides an affordable anti-theft alternative for bicycle owners. The circuit uses a 9V battery, key lock switch, and tone generator integrated circuit to sound an alarm if the security loop between its two input jacks is broken. The simple circuit can be assembled on a small printed circuit board and housed in an enclosure to attach to bicycles in place of a standard lock.
Dtmf reciever ic mt 8870 tester
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Drinking water alarm
This document describes a drinking water alarm circuit that notifies people when water supply resumes. It uses a simple water sensor made of aluminum and plastic foil rolls to detect water flow. When water touches the sensor, it completes a circuit that triggers a 555 timer chip configured as an astable multivibrator. The timer chip's output is connected to a loudspeaker to produce an audible alert. The circuit can be assembled on a PCB and housed in a cabinet to install the water sensor in the tap, allowing it to sound an alarm whenever the water supply starts again.
Desktop power supply
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Current sensor
The document describes a non-contact current sensor circuit that detects current flowing through high-wattage appliances and provides an audible alert every 15 minutes. It uses a step-down transformer as a current sensor, whose primary winding ends are connected to a full-wave bridge rectifier. The rectified output is fed to an op-amp comparator IC. When current is detected, the op-amp output triggers a 14-stage ripple counter IC to generate periodic signals that activate a buzzer through a transistor oscillator circuit, reminding the user that the appliance is still on.
Computerised universal timer
This circuit provides a universal timer functionality that can be used to automatically switch electrical devices on and off after preset time intervals. The program was written in QBasic and allows the user to set the timer in increments of 10 seconds by pressing F1. Once set, pressing F2 will turn the device on and start the countdown. The timer output is connected to the computer's parallel port to control power to the device. When the display reads 0:0:0, the device will turn off. This simple, low-cost timer circuit can be used in applications like laboratories, darkrooms, and time-keeping for educational competitions.
College quiz buzzer
This circuit allows up to 8 players to buzz in during a quiz competition. It uses an IC and passive components to identify the first player to press their button. The circuit is divided into a power supply section and a quiz buzzer section. The power supply generates 5V from mains power. The buzzer section uses an octal latch IC to transfer the button press signals to corresponding outputs. When a button is pressed, the corresponding bulb lights and a buzzer sounds to identify the player.
Clap switch
This document describes a clap switch circuit that uses two integrated circuits and a microphone to turn an appliance on or off based on detecting two claps within 3 seconds. The microphone detects claps and sends signals to timer IC1 and IC2. On the first clap, IC1 provides power to IC2 and lights an LED for the preset time. On the second clap within that time, IC2 triggers a decade counter that changes the output state to turn the appliance on or off. The circuit costs around 80 rupees to build.
Child's lamp
This document describes a mini emergency lamp circuit for a child's study room that uses a light sensor and LED flasher. When ambient light is present, the light sensor keeps the flasher circuit powered off. When it gets dark, the light sensor activates the flasher circuit, causing a white LED to flash on and off instead of staying continuously lit, to conserve battery power. The circuit is built around a CMOS IC oscillator and uses a light-dependent resistor, transistors, diode, and other passive components to trigger the LED flashing when light levels drop. The flashing rate is about once per second to serve as an emergency light for the child to safely exit the room during a power outage.
Car anti theft guard
This document describes a simple car anti-theft circuit that uses a door switch, transistor, SCR, relay, and buzzer to alert the owner if someone opens the car door. When the door is closed, the circuit is in sleep mode. When the door opens, the transistor conducts, triggering the SCR to energize the relay and sound the buzzer, alerting the owner that someone is accessing the car. To reset it, the owner turns the car key switch off, cutting power to the circuit and stopping the buzzer.
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This circuit provides an audio-visual warning of potential brake failure in vehicles. It constantly monitors the brake switch and uses an op-amp voltage comparator and monostable timer to detect changes in the brake switch voltage. When the brake is applied normally, a green LED blinks and buzzer sounds briefly. If brake fluid pressure drops, the red LED will remain lit and buzzer will not sound, alerting the driver to potential brake failure. The circuit can operate from the vehicle's battery and regulated power supply to avoid unwanted triggering.
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Digital stop watch
- 1. CIRCUIT IDEAS DIGITAL STOP WATCH S.C. DWI VED I C.H. VITHALANI push-on-switch S3. When S2 is momen- Thus, when switch S3 is pressed, reset tarily pressed, the count value becomes pin 13 of IC2 is connected to ground H ere’s a digital stop watch built 0, transistor T1 conducts and it resets via transistor T1 and the oscillator does around timer IC LM555 and 4-digit IC1. Counting starts when S2 is in ‘off’ not generate clock pulses. This is done counter IC with multiplexed 7-seg- condition. to achieve synchronisation between IC1 ment output drivers (MM74C926). A low signal on the latch-enable input and IC2. IC MM74C926 consists of a 4-digit pin 5 (LE) of IC2 latches the number in First, reset the circuit so that the dis- counter, an internal output latch, npn the counter into the internal output latches. play shows ‘0000.’ Now open switch S2 output sourcing drivers for common- When switch S2 is pressed, pin 5 goes for the stop watch to start counting the cathode, 7-segment display and an low and hence the count value gets stored time. If you want to stop the clock, close internal multiplexing circuitry with four in the latch. Display-select pin 6 (DS) de- switch S2. multiplexing outputs. The multiplexing cir- cides whether the number on the counter Rotary switch S1 is used to select the cuit has its own free running oscillator, or the number stored in the latch is to be different time periods at the output of the and requires no external clock. The displayed. If pin 6 is low the number in astable multivibrator (IC1). The circuit counter advances on negative edge of the output latch is displayed, and if pin 6 works off a 5V power supply. It can be the clock. The clock is generated by timer is high the number in the counter is dis- easily assembled on a general-purpose IC LM555 (IC1) and applied to pin 12 played. PCB. Enclose the circuit in a metal box of IC2. When switch S2 is pressed, the with provisions for four 7-segment dis- A high signal on reset pin 13 of base of pnp transistor T2 is connected to plays, rotary switch S1, start/stop switch IC2 resets the counter to zero. Reset pin ground and it starts conducting. The emit- S2 and reset switch S3 in the front panel 13 is connected to +5V through reset ter of T2 is connected to DS pin of IC2. of the box. JULY 2004 ELECTRONICS FOR YOU