Overhauling LED Marquees

November 14, 2008 by Eliot 11 Comments

led-sign

In a previous job, [sprite_tm] was responsible for wrangling many different LED text ad marquees. The hardware was fairly simple and he always figured they could be pushed much further with a little work. He recently acquired ten 32×16 LED displays a decided to see what he could do with them. By the end of the project, he had full motion video running on the display. This is a great project to read up on if you’ve ever wondered about LED matrix displays. He starts by reverse engineering the electronics on the board. He then attached an ATmega88 to drive the display module. Multiple display modules were daisy chained together over serial. The article covers PWM control and refresh timing as well. Check out one of a few demo videos below. Continue reading “Overhauling LED Marquees” →

Scratch Built RFID Tags

November 11, 2008 by Eliot 17 Comments

rfid

[nmarquardt] has put up an interesting instructable that covers building RFID tags. Most of them are constructed using adhesive copper tape on cardstock. The first version just has a cap and a low power LED to prove that the antenna is receiving power. The next iteration uses tilt switches so the tag is only active in certain orientations. The conclusion shows several different variations: different antenna lengths, conductive paint, light activated and more.

Messing With Barcodes

November 10, 2008 by Eliot 13 Comments

[nico] just received his credentials for an upcoming conference. On each badge, there’s a 2D barcode with the participant’s bio and contact info. These are meant to be scanned by vendors for future contact. [nico] isn’t so interested in that and plans on updating his personal info by generating a new barcode. To this end, he’s collected a number of links to help out barcode hackers. He used the SWIPE toolkit to identify the format and decode (it has an online component too). There are also several online encoders you can use, like this one from [Terry Burton]. If you’re wondering what sort of shenanigans you can get into faking barcodes, check out [fx]’s presentation from 24C3.

[photo: seanbonner]

Easy High Voltage Power Supply

November 10, 2008 by Eliot 16 Comments

hv_supply

[rocketman221] wrote up one of the simplest ways to build a high voltage power supply. This one in particular was used on his coilgun. Instead of building a custom circuit, he’s using flash charging boards from disposable cameras. Six 450V 470uF caps are wired in parallel to make up the bank. Two of the charger boards are wired to one switch to initiate the charging process. Four additional boards are wired two a second switch for the second charging stage. The part cost on this is incredibly cheap and it only requires a 3.3V input to reach 450V. The writeup has plenty of warnings about the dangers of high voltage; you need to clean off all flux residue to prevent arcing across the circuit boards. Embedded below is a video of the bank being discharged through several objects. Continue reading “Easy High Voltage Power Supply” →

Best New Science Inventions 2008

November 10, 2008 by Kimberly Lau 8 Comments

Not to be outdone, Popular Science published their Best of What’s New 2008 and packed it with videos and photo galleries. Inspiring inventions include the Pipistrel Taurus Electro, the longest-flying two-seated electric plane, the Intel Core 2 Duo Small Form Factor, which you can thank for the thinner laptops like Apple’s MacBook Air, and the GroundBot, a spherical robot that can roll through the mud, sand, and snow. It’s not even the end of the year yet, but with all these great inventions, we can’t wait to see what’s in store for 2009.

[via io9]

Kill A Watt Teardown

November 10, 2008 by Eliot 16 Comments

killawatt

Come on, folks. If we keep tearing apart everything that’s handed to us, we’ll never get nice things. SparkFun got their mitts on two Kill A Watts and proceeded to plug them into everything and then dismantled them to see how they work. The Kill A Watt keeps track of how much power is used over time. The largest load they found was their soda machine using 500W (should probably add a motion sensor to that). They plugged a meter on either side of a UPS and found out that it uses 5W just to charge. On the inside of the meter, there isn’t anything too substantial. One unlabeled IC runs the whole show.

Weasure, A Scale That Weighs And Measures

November 9, 2008 by Eliot 2 Comments

weasure

[John Peterson] created this postal scale device for a Renesas design contest. The Weasure not only calculates the package’s total weight but the dimensions as well. He built it using a SKP16C62P evaluation board that had an LCD, pushbuttons, and indicator LEDs. The original DigiWeigh parcel scale was modified to provide PWM output and tare control. He embedded photoresistors every inch along each axis. They were angle slightly upward and the surroundings were painted black to minimize reflection. The Weasure outputs everything via a serial connection so it can be used with shipping software to generate postage.