Ondrej Karas of DoItWireless writes:
This is simple illustration how to build easy PWM LED control with IQRF TR module and a few other components.
This device is powered from 12V/6A DC power supply and can power up to 5m of LED strip. This device can be controlled via RF, buttons or potentiometer. RF controlling is compatible with remote control device RC-04 with low battery signalizing – fast 3 time LED blinking.
RF PWM LED control - [Link]
The LTC3350 is a supercapacitor charger and backup controller IC that includes all of the features necessary to provide a complete, standalone capacitor-based backup power solution. Many applications require reliable short-term uninterrupted power in the event of a main power failure. Examples include data backup for solid state drives (SSDs) and nonvolatile dual in-line memory modules (NVDIMMs), power fail alarms in medical and industrial applications, as well as a host of other “dying gasp” power fail indicators. The LTC3350 provides all PowerPath control, capacitor stack charging and balancing, and capacitor health monitoring to ensure that the backup system is capable of reliable operation.
LTC3350 – High Current Supercapacitor Backup Controller and System Monitor - [Link]
by Chang Fei Yee @ edn.com:
This paper discusses the essential steps taken to achieve a low-EMI prototype before conducting compliance tests in an anechoic chamber. These steps include electronic circuit design for minimal radiation, and pre-compliance inspections. The pre-compliance inspections include simulated EMI analysis of a printed circuit board (PCB) layout model using 3DEM software, and a near-field EM scan of the prototype PCB using a spectrum analyzer (SA). Success is confirmed by anechoic testing.
Build low-EMI prototypes: The essentials - [Link]
By Sergey Feingold @ makezine.com:
For makers, engineers, and DIY enthusiasts, Shenzen, China is a bit of a dream world. Once you get past the shoddy internet and questionable origin of the components you buy in the markets, you realize just how quickly and easily you can get almost anything done. For about $100 you can get a couple dozen 4-layer PCBs and a stainless steel stencil. For another $50 you can get it in 2 days. That’s seriously cheap, and the game changes when you have such ready access to fast, cheap manufacturing. The electronics market puts Wal-Mart to shame, and you can’t walk 20 feet without bumping into someone carrying a reel of components or pushing a cart full of capacitors. I was there with Lavie Sak, my co-founder for Shot Stats, makers of Challenger, a tennis swing tracking device. We were excited and overwhelmed by this new place and it seemed like anything was possible.
Prototyping a Tennis-Tracking Device in Shenzen: A Lesson - [Link]
ElecFreaks @ elecfreaks.com writes:
We were just wondering in the current market where capacitive touch screens, resistive touch screens, TFT displays are flooding, DIY enthusiasts have been rarely used dot matrix screens. Here we use 5mm 8 * 8 dot matrix screen and phototransistor to achieve a pen write function. Sounds fun? But how to specifically make it? Can we achieve a larger area pen write?
Dot Matrix Pen Write Screen - [Link]
Ondrej Karas of DoItWireless writes:
This article describes temperature and humidity measurement with DHT11 sensor connected to TR module. Circuit diagram is very simple. You need only power supply for sensor and one wire for data line. This line has to be “pull-uped” – sensor has open collector output.
Temperature and humidity measurement with DHT11 - [Link]
Jack Arcade @ jameco.com writes:
Flashlights are always useful especially if you like to camp like me. Out in the woods, when you are away from your iPhone flashlight, a Mini Maglite comes in real handy. Now, what if you hate its yellow color and carrying extra batteries? What if you want a white color for your flashlight and a longer battery life? Sound exciting? Let’s make one.
Convert Your Mini Maglite to LED - [Link]
Another Instructables by Jan Henrik, a police light with a Attiny25/45/85. He writes:
Hello, in this project I want to show you how to build a multi functional Police Light with a Attiny25/45/85 .
It will have several animations , which can be changed with a button on the circuit board, it has 2 channels, which can be controlled with PWM. That allows us to add serval animations or police light flashing sequences. The maximum rated current per channel is 500mA, that allows us to control high power LED´s, LED stripes or old Light Bulbs!
Attiny25/45/85 police light with Arduino - [Link]
Over 90 % of the worlds solar cells are made from silicon but they are not particularly efficient at converting light to energy. They are made from layers of high purity crystal more than 150 micrometers thick which is costly to produce. Thin-film solar cells are an alternative technology; they convert the sun’s energy using a more efficient semiconductor process and can get similar efficiency using lower purity material that is only 2 micrometers thick. This results in much lower production costs.
The majority of thin-film cells are made from a sandwich of cadmium telluride and cadmium sulfide (CdTe/CdS) which, thanks to recent advances are now approaching the efficiency of silicon cells. The problem with this technology is that cadmium based products are extremely harmful to living organisms. Researchers at Liverpool University in the UK have discovered that magnesium chloride is a good alternative to cadmium chloride. It is extracted from sea water and has uses such as road de-icing and as a coagulant for tofu, the vegan protein foodstuff based on soy milk.
Vegan Additive makes Non-toxic Solar Cells - [Link]
By Dean Segovis @ makezine.com:
A transistor is an electrical component that functions, most basically, as a switch — in principle not so different from a light switch. Instead of a physical movement, however, a transistor is controlled by a flow of electricity. And unlike your basic light switch, a transistor can be on, off, or somewhere in between.
Non-Contact Voltage Detector - [Link]