My variable AC power supply has gone through several revisions over the years. It started out as a simple unenclosed variac (variable autotransformer) and electrical outlet mounted on a block of wood. I eventually put it in the case of what used to be an old audio signal generator for safety and appearance. Among the other added features, I used a 0-250VAC analog meter that I had on hand to display the output voltage because otherwise it was annoying to whip out the multimeter to monitor the voltage coming out of the variac. Over the years I realized that the meter was inaccurate and simply useless, so a new readout was necessary.
Digital AC Voltmeter - [Link]
One of the earliest methods of wireless transmission used was with infrared light. Using wireless IR links has many advantages with the primary two being low cost and low part count to implement. The simplest of on/off switches using wireless IR would take no more than 10 parts, but this tutorial will be going to send asynchronous serial data over a wireless IR link.
This tutorial will create a wireless infrared transmitter using an IR LED and a wireless IR receiver using a phototransistor. Asynchronous serial will be transmit over this link at 9600 BPS. The PIC 18F452 will be used to transmit and receiver this data.
Wireless Infrared Link - [Link]
Remembering to take a vitamin daily is simple enough. Remember to take a vitamin every three days is nearly impossible (for me). I wanted a solution which will remind me to take the pill and require zero effort. This small project holds two bottles in a fairly nice looking box and flashes red until you take the pill. The act of picking up the bottle (the pill ingestion is assumed) is the entire interface.
Pill Reminder - [Link]
Aktakom redefines the meaning of the functional yet affordable oscilloscope by introducing to the market the newest series of smart, affordable oscilloscopes that feature up to 300MHz bandwidth and 32 automatic measurement functions.
Miami Fl., July 25, 2011 – T&M Atlantic., distributer of the test and measurement equipment today unveiled a new series of digital oscilloscopes by AKTAKOM. These newest instruments achieved the quality, speed and functionality of world leading brands, yet sold for the fraction of the price. ADS series of oscilloscope feature 25 – 300 MHz bandwidth, 2- 4 channels with a 500M – 2GSa/s sample rates as well as a 7 inch color TFT-LCD screen. Models marked with the letter M in the model number offer huge amounts of memory up to 10Mpts. All devices in the series come with USB and some with the additional LAN interfaces, allowing control of the device from the PC, as well easy flash storage support.
32 Automatic measurements functions don’t just make these devices smart but also functional. For example, these oscilloscopes can detect the peak and average values of a waveform and store as much as 5000 waveform points on each channel. Besides peak and average the list of automatic measurement functions includes: Vpp, Vmax, Vmin, Vamp, Vtop, Vbase, Cmean, Mean, Vrms, Crms, ROVShoot, FOVShoot, RPREShoot, FPREShoot, Freq, Period, Rise time, Fall Time, +Width, -Width, +Duty, – Duty, BWid, Phase, FRR, FRF, FFR, FFF, LRR, LRF, LFR and LFF.
These smart oscilloscopes could be utilized for electronic circuit debugging, design and manufacturing, maintenance and testing, circuit testing, education and training. More information can be found at www.tmatlantic.com
Introductory Prices start from $299.00
AKTAKOM ADS – The Series of Smart, Affordable Oscilloscopes - [Link]
Although optical touch screens are available in a wide variety of designs they do share a common principle in that the touch of a finger will either cast a shadow or reflect light. In basic versions an array of infrared emitters (IREDs) and detectors create a grid of vertical and horizontal beams. The components are housed in a low-profile frame, known as the bezel, measuring a half to one millimeter in depth around the screen.
Osram’s new ChipLED SFH 4053 measures just 0.5 x 1 mm so it takes up very little space. With a height of 0.45 mm in industry standard 0402 (length/width) it is one of the smallest on the market. [via]
ChipLED for ultra low profile displays - [Link]
Atmel announced additional unique features to the already-successful 8/16-bit AVR XMEGA microcontroller (MCU) family with the industry’s lowest power consumption of 100nA with 5µS wake-up time. The new Atmel AVR® XMEGA® family includes full-speed USB, the fastest and highest-precision analog systems, a Direct Memory Access (DMA) controller and the innovative event system that maximize real-time performance and throughput while reducing CPU load. This new family lowers overall system cost through higher integration, capacitive touch support, and ultra-low power consumption. The AVR XMEGA microcontrollers are designed for applications in the industrial, consumer, metering and medical segments. [via]
Atmel AVR XMEGA Series with USB and High-precision Analog - [Link]
Taking a cue from ‘whispering galleries’ built into cathedrals by Renaissance architects, researchers at the University of Pennsylvania adapted the principle to nanoscale devices to drastically reduce emission lifetime, a key property of light-emitting semiconductors. A whispering gallery is a circular chamber designed to reflect and direct sound waves so that a whisper can be heard across the room.
When a semiconductor material is excited, it takes a few nanoseconds to return to the ground state, which is accompanied by emission of light. This delay is called the emission lifetime. For devices such as modulators, which must switch back and forth between two states, the emission lifetime sets a limit to the switching rate. The novel approach taken by the researchers reduces the emission lifetime to less than a picosecond – more than a thousand times faster than anything else currently available. [via]
Nanoplasmon ‘whispering gallery’ slashes emission lifetime in semiconductors - [Link]
US semiconductor technology company RoseStreet Labs (RSL) has announced what it claims to be the world’s first long wavelength LED device built on a low-cost silicon wafer substrate. According to RSL, LEDs operating at green or longer wavelengths would fill a demand gap in the rapidly growing commercial and industrial markets for lighting and illumination.
RSL’s device compliments its proprietary thin-film InGaN-on-silicon technology for high efficiency photovoltaic applications and power devices. These longer wavelength devices are fabricated using commercial scale deposition tools at RSL’s Nitride Research Center in Phoenix, Arizona. Silicon substrates have a substantial cost advantage over the more traditional sapphire or silicon carbide substrates typically utilized in LED fabrication, the company claims. [via]
Novel green LED built on silicon substrate - [Link]
Researchers at the California Institute of Technology (Caltech) have now created the first tunable acoustic diode-a device that allows acoustic information to travel only in one direction, at controllable frequencies.
The mechanism they developed is outlined in a paper published on July 24 2011 in the journal Nature Materials.
Borrowing a concept from electronics, the acoustic diode is a component that allows a current — in this case a sound wave — to pass in one direction, while blocking the current in the opposite direction.
The new mechanism brings the idea of true soundproofing closer to reality. Imagine two rooms labeled room A and room B. This new technology would enable someone in room A to hear sound coming from room B; however, it would block the same sound in room A from being heard in room B. [via]
Acoustic diode developed - [Link]
Satellite design team launches blog about project; deployment to be broadcast live on NASA TV and online
A volunteer team of Microchip engineers spent nearly four years working on nights and weekends to develop the ARISSat-1 amateur satellite. On August 3 at 7:30 a.m. (Pacific Time) their hard work will come to fruition when the crew of the International Space Station (ISS) is scheduled to deploy the satellite during a spacewalk.
The deployment will be broadcast live on NASA TV and online. Additionally, ARISSat-1 design-team leader Steve Bible launched the limited-series Chips in Space Blog on EE Times’ Web site last week, to both educate and entertain readers by relating the story of how he and his colleagues came to build the satellite, and the challenges they ran into along the way. Bible will also provide analysis of the satellite’s deployment and functionality. [via]
ARISSat-1 Amateur Satellite built by Microchip engineers - [Link]