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Things to make and do.

Things to make and do.

Hack your solar garden lights. Solar garden lights.... How on earth do they manage to sell something with a solar panel, rechargeable battery, step-up converter, LED and the plastic and metal casing for a dollar/pound. You can't even buy the bare components for anywhere near that, in fact the solar panel alone would probably cost you five times the cost of the whole light! This project is about hacking your solar lights to make them different colours and potentially increasing the battery life too.Solar lights are great to hack. Here's the test subject for this project. Inside is a small NiMh cell and a PCB with the LED, a small inductor, a switch and a COB (Chip On Board) which is basically a bare integrated circuit which is stuck to the board, connected and then covered with a blob of black resin. If the LED pads have solder left across the holes then it can be removed with a bit of desoldering braid, which is a fine braided copper wire soaked in resin. And test by turning the light on and covering the solar cell.

Basic Electronics {*style:<b> Get a quick start by scrolling down to the introduction below this menu table. Basic Electronics - Course Table You are at the best, free online "Basic Electronics Course". {*style:<b><b>Maybe you already know some basic electronics and want to test yourself to see exactly how much you do know. </b></b>*} {*style:<b>Explanation of AC and DC currents. </b>*} {*style:<b><b><b> P - I*V </b></b></b>*} {*style:<b>Watch the video . If you don't have a clue as to what electrical current and voltage are - read on. DC Theory Part 1 - DC Theory part 2 {*style:<b> </b>*} More book recommendations. There is another (and less expensive and practical) method of learning basic electronics. It is hands-on by doing simple projects. Get the MAKE: Electronics (Learn By Discovery) book below. You will also need some electronic parts available from Radio Shack or a good junk box. {*style:<b><b>Combined resistance of two resistors in parallel: </b></b>*} <b><b>Black </b></b> <b><b>Brown </b></b> <b><b>Red </b></b>

LICENSE PLATES OF THE WORLD Europlate# 701 If you do not see this page with frames click here Giant asteroid will zoom past Earth, averting apocalypse By Lisa M. Krieger Posted: 02/07/2013 04:05:02 PM PST0 Comments|Updated: about a year ago An asteroid the size of a 15-story building will zoom past the Earth next week, the closest such flyby in a century and a reminder of the persistent risk of collision. In a different orbit from outer space, the spinning rock, dubbed DA14, could have struck the Earth with a force equivalent to more than 2 million tons of TNT. But instead, it will continue on eight times as fast as a speeding bullet back into deep space, averting calamity and thrilling scientists. "It is a record-close approach for an asteroid of this size," said Donald Yeomans, manager of the Near-Earth Objects Office at NASA's Jet Propulsion Laboratory in Pasadena, in a Thursday morning news conference. This image provided by NASA/JPL-Caltech shows a simulation of asteroid 2012 DA14 approaching from the south as it passes through the Earth-moon system Feb. 15, 2013.

Homo ludens electronicus My interest in electronics started when I was 12 years old, although I had built electric devices (lighting systems, flashlights, solenoids, even a motor) much earlier. At age 12 I started the real thing: Radios, sound effect generators, light games, etc. This obsession of building things led to a career in electronics, but also it has become my most interesting hobby. I regularly design and build things, and now I will share my better documented projects with you. Each of the following links leads to a page giving constructional information (schematics, sometimes printed circuit layouts, and text) for an electronic project. Power supply and switching technology 13.8 Volt, 20 Ampere linear power supply: A semi-traditional power supply for communication equipment, using negative-rail regulation with grounded pass transistors in a configuration that gives some unique advantages. 160 Volt, 3 Ampere DC motor power supply: A very compact, efficient and simple off-line buck regulator. Audio

Asteroid 2012 DA14 – Earth Flyby Reality Check Update Feb. 15, 2013 NASA's Near-Earth Object Program Office can accurately predict the path of the small near-Earth asteroid 2012 DA14. There is no chance that the asteroid might be on a collision course with Earth. This small near-Earth asteroid is passing very close to Earth on February 15, so close that it will pass inside the ring of geosynchronous weather and communications satellites. FREQUENTLY ASKED QUESTIONS VIDEOS TRAJECTORY DIAGRAMS Graphic depicts the trajectory of asteroid 2012 DA14 on Feb 15, 2013. Graphic depicts the trajectory of asteroid 2012 DA14 during its close approach, as seen edge-on to Earth's equatorial plane. Electronic Circuits Also, use the search box at the bottom of the home page. Audio Circuits Audio Amplifier CircuitsDirectional MicrophoneAGC Dynamic MicrophoneVery Low Noise AmplifierInduction Receiver White and Pink (1/F) Noise SourceNoisemaking Circuits (police siren and doorbell chime) Telephone Circuits Computer Data Logging Circuits Meter Circuits Meter/Data Acquisition AmplifierCD4069 LED Bar Graph - smooth transitions between 5 LEDs.Measuring RF Voltages with a VOM Microprocessor Circuits PicAXE Ionization ChamberKeyboard WedgieAltoids Tin LowFER Transmitter Miscellaneous Oscillators Two-Transistor Atomic Frequency StandardCD4069 Atomic Frequency Standard (I know, a little overstated.)Audio OscillatorsFlip-Flop Flashers, Buzzers, Etc.Flasher Ideas (LED flasher, silent metronome, low battery indicator, high voltage generator)Tiny Crystal Oscillator High-stability gate oscillator uses two, 5-pin SOT packaged devices. Power Control Power Supplies /Regulators Radiation Circuits RF Circuits Science

Microsoft Surface Pro Review: The Weirdest Mainstream Laptop You Can Buy The Microsoft Surface Pro is easily the most interesting laptop to cross my desk in the past few years. Not the best, but certainly the ballsiest and most unusual. And it is a laptop; this isn't a tablet, like its confusing sibling, the Surface RT, which looks nearly identical and was released late last year for half the price of this one. Instead it's an experimental ultraportable, like Lenovo's Yoga 13 (our favorite early Windows 8 laptop), which innovates with form and aesthetics while remaining, distinctly, a laptop. What's Good The size, shape, and build quality are all great. The screen is fantastic--not quite as sharp as a retina display on a MacBook Pro, but remember that this machine starts at $900, and the cheapest retina MacBook starts at $1,700. It has minimal ports, but I didn't find that a problem--if you're buying what's probably the smallest and most portable full-figured computer out there, you can't expect it to have six USB ports and five ways to output video.

Bowden's Hobby Circuits