Beginner Concepts: Powering Your Projects

Powering your gadgets generally seems like a necessary evil. To help with this [Felipe La Rotta] made a really nice bench power supply using a PC power supply and a LM317 adjustable voltage regulator. PC power supplies are an example of a switched power supply(more on that later).  The LM317 is a type of linear voltage regulator that allows for adjusting the output voltage by varying some resistors. Whats the best way to power your circuits? well that depends…

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Beginner Concepts: LEDs And Laws

Adafruit has a new LED tutorial for people wanting to get started with electronics. It is full of useful diagrams, pictures, and quizzes to help make sure you are understanding the concepts. This is the real basic stuff here: LEDs, resistors, and the laws from Kirchhoff, and Ohm. It starts out explaining the parts of an LED. Then variations of LEDs: illumination versus indication, clear versus diffused, brightness, color, and size. The mass of the tutorial covers how and why an LED’s brightness can be changed by a resistor and why a resistor is needed to keep an LED from burning out. Such as how Kirchhoff’s Voltage Law works with Ohm’s Law to help you determine the proper resistor for an LED. If you found useful the other beginner concepts posts about Analog Circuits and Electronics basics from the Giz, you should find this tutorial to be useful.

Test Beds And Jigs With Pogo Pins

Pogo pins – spring-loaded pin contacts are pretty fun to play with and even cooler when they get used in electronic devices like Adafruit and SparkFun’s test jigs. Check after the break for how these two companies have created their own production hacks. Continue reading “Test Beds And Jigs With Pogo Pins”

Human Tetris: Object Tracking On An 8-bit Microcontroller

Elaborating on an item previously mentioned among last weekend’s Cornell final projects list, this time with video:

For their ECE final project, [Adam Papamarcos] and [Kerran Flanagan] implemented a real-time video object tracking system centered around an ATmega644 8-bit microcontroller. Their board ingests an NTSC video camera feed, samples frames at a coarse 39×60 pixel resolution (sufficient for simple games), processes the input to recognize objects and then drives a TV output using the OSD display chip from a video camera (this chip also recognizes the horizontal and vertical sync pulses from the input video signal, which the CPU uses to synchronize the digitizing step). Pretty amazing work all around.

Sometimes clever projects online are scant on information…but as this is their final grade, they’ve left no detail to speculation. Along with a great explanation of the system and its specific challenges, there’s complete source code, schematics, a parts list, the whole nine yards. Come on, guys! You’re making the rest of us look bad… Videos after the break…

[G’day Bruce]

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Minimalist AVR Programmer Is Just Fab!

Whether you’re burning a new bootloader to an Arduino board, or doing away with a bootloader to flash Atmel chips directly, an in-system programmer (ISP) is an indispensable tool for working with AVR microcontrollers. If cost has held you back, it’s no longer an excuse: FabISP is a barebones USB-based AVR programmer that can be pieced together for about ten bucks.

FabISP was created by [David Mellis] as a product of MIT’s Fab Lab program, which provides schools with access to design and manufacturing tools based around a core set of fabrication capabilities, so labs around the world can share results. But the FabISP design is simple enough that you don’t need a whole fab lab. It’s a small, single-sided board with no drilling required; the parts are all surface-mounted, but not so fine-pitched as to require reflow soldering. Easy!

There’s still the bootstrap problem, of course: you need an AVR programmer to get the firmware onto the FabISP. This would be an excellent group project for a hackerspace, club or school: if one person can provide the initial programmer to flash several boards, each member could etch and assemble their own, have it programmed, then take these out into the world to help create more. We must repeat!

[Thanks Juan]

Report From ESC Silicon Valley 2010

Ah, the heady aroma of damp engineers! It’s raining in Silicon Valley, where the 2010 Embedded Systems Conference is getting off the ground at San Jose’s McEnery Convention Center.

ESC is primarily an industry event. In the past there’s been some lighter fare such as Parallax, Inc. representing the hobbyist market and giant robot giraffes walking the expo. With the economy now turned sour, the show floor lately is just a bit smaller and the focus more businesslike. Still, nestled between components intended to sell by the millions and oscilloscopes costing more than some cars, one can still find a few nifty technology products well within the budget of most Hack a Day readers, along with a few good classic hacks and tech demos…

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DIY Diodes

[H. P. Friedrichs], the creator of the Static Bleeder has created his own diodes. Using household chemicals, a film of cuprous oxide was made on a copper pipe cap. Cuprous oxide has been one of the first known semiconductor substances, has a low forward drop but is an otherwise asymmetrical conductor, odd V-I curves, and some neat photovoltaic action. The apparatus seen above is used to bring a piece of lead (in this case, solder) into contact with the salmon-colored cuprous oxide while electrical connections can be made to the binding posts at the front. What are your thoughts on this device?