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An Easy-To-Use LCR Meter Miguel‘s portable LCR meter makes it easy to analyze the analog performance of virtually any device under test， whether in the lab or on the job.The dsPIC30F4012-based meter uses DDS techniques and DSP methods to condition the resulting voltage and current signals. Its handy user interface and graphic LCD make it easy to operate and read. In the back of my mind， I keep two lists of tools that I would like to add to my electronics workbench. The first is made up of too...

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Build a Simple USB DAC Yoshiyasu describes the step-by-step construction of a simple USB DAC around an ATtiny45 and a MAX517.You can use the system as a programmable power supply. In this article， I‘ll explain how USB communication can be implemented on an Atmel ATtiny45 eight-pin DIP with open-source software packages（libusb， Cygwin， WinAVR， and AVRUSB）。WinAVR compiles the target firmware program under Windows. AVR-USB is an open-source USB protocol stack for firmware， which can be com...

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Build A Variable-Speed Drive For Motors Richard's single-phase, variable-speed drive for AC induction motors is an excellent device for powerful, yet quiet, pump operation. Designed for use with a capacitor-start/capacitor-run motor, it includes active power factor correction (PFC) and inrush current limiting. Over the past few years， I‘ve done various renovations to my house，including adding a new backyard deck to support a hot tub. Last year， I finally decided to buy one. I looked for a se...

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Target And Display Web Site Content Fernando's SwissJazz system retrieves artist and song title information from an Internet radio station's web site without a PC. Information is shown on an LM3S811 evaluation board's display and updates every time a new song begins. What type of music do you listen to？Here in Switzerland， I listen to Radio Swiss Jazz， which plays jazz music around the clock. The problem， however，is that the station doesn‘t announce artist and title information for the son...

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Build A System For Powering AC Induction Motors The Electric Vehicle （EV） Inverter project is a starting point for the conversion of a vehicle with a gas engine to one with an electric motor. The inverter was built using a control board and software based on Microchip Technology‘s MC-1 development board. The finished design can power a wide range of AC induction motors. The world is in the process of advancing alternative sources of energy， and the concept of electric vehicle （EV）conversio...

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Build an Internet-Connected News Ticker James no longer has to turn on a TV or computer to get news updates. His innovative design retrieves news headlines from RSS feeds and constantly scrolls them across a dot-matrix LED display. The system checks for updates every 15 minutes When I first heard about WIZnet‘s iEthernet 2007 design contest， I was really excited about all of the possibilities an integrated Ethernet chip would open up to smaller microcontrollerbased systems. I knew there were t...

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Construct An Ultrasonic Snow Depth Sensor Gerhard used the sonar components from an autofocus camera, a Microchip PIC18F452 microcontroller, and several off-the-shelf parts to construct an ultrasonic snow depth sensor system. The low-power design provides accurate snow depth measurements and is easy to integrate into other weather station systems. Snowfall and snow depth measurements are important to anybody who receives regular snowfall. Several traditional methods of measuring snow accumulatio...

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Ring Signal Detection And Interpretation You'll never miss another voicemail message with Peter and Monica's voicemail monitoring system. Their device monitors the signal from an analog phone line, analyzes it, tracks the number of calls and messages, and displays the number on a VFD. In some institutions， the internal phone exchange system （aka private branch exchange， or PBX） offers voicemail，but it can‘t drive the "Message Waiting" indicator （typically a flashing light）。 In other ins...

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Unlike old-school mechanical alarm clocks that you have to set manually， DJ‘s Internet-connected alarm clock provides three primary features： automatic time setting on power-up，streaming MP3 music， and remote management. The PIC24FJ64-based clock is connected to an ENC28J60 Ethernet chip， an MP3 decoder chip， an organic LED graphical display， and a 24LC512 EEPROM for storage. My wife is a morning person. She gets up at the crack of dawn and goes to bed early. I‘m more likely to wake at ...

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A Virtual Linux Environment on a Windows System Imagine this: a flexible embedded Linux development environment running under Windows.Now it's a reality. David created a virtual Linux environment on a Windows system usingcoLinux. This is your platform for embedded cross development. The development environment for my first system consisted of LEDs and switches. Today， embedded developers expect capable tools for the systems they work with. Embedded systems are getting smaller，more powerful， c...

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Dennis describes an efficient method for detecting FSK signals using a correlator and analog signal processing in a PSoC. The method is readily applicable to caller ID technology. When combined with a UART， it forms the core of a Bell 202 half-duplex modem. Frequency shift keying （FSK） is the modulation cornerstone of a number of digital data transmission systems. The transmit signal is fairly easy to generate. Receive processing is tolerant of a wide range of signals and relatively immune to...

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Miguel explains how to build a vertical plotter system that can draw on canvas with a pencil or charcoal stick. The compact, portable system consists of a pen holder hanging from pulleys on two stepper motors. In this article, he describes the entire process, from hardware development to programming the system. Throughout history, painters have used whatever technology was available to help them with their art. It is believed that Johannes Vermeer, like other Dutch masters, used a dark chamber t...

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Ada95 is a standardized object-oriented programming language that was developed in the late 1970s by the U.S. Department of Defense. Today, engineers like Daniel use the highly structured language to increase the safety and reliability of their new robotics applications. What do robots in space, the International Space Station, the Canadian robot arm, the European Arienne rocket, the Boeing 767, the Eurobus jet, and the French Grand Vitesse bullet train have in common? The answer is Ada95, a com...

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Obtain Lighting Control Via Ethernet Ready to build your own DMX lighting controller? Matt’s design enables him to remotely control up to 512 channels through an IP-based network or directly interface them to embedded systems with a serial connection. It is perfect for distributed lighting systems where low-cost Ethernet wiring is a better option than RS-485 wiring. The DMX Portal is a self-contained lighting control unit that you can use to control moving lights or special effects equipped wit...

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Victor and Serhiy’s USB optical mouse enables you to measure your pulse rate while you work at your PC.You can design a similar system for numerous other sensory applications. Over the past few years, mouse manufacturers have been trying to improve the functionality and performance of their devices. Some companies have added buttons and Zwheels to their mice. Other manufacturers have developed optical units featuring capacitive sensor buttons. As a result, the average consumer can choose from a...

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