A simple project to read a POT and control a couple LEDs using the very cool looking and cheap Arduino.
Maybe the Arduino could be used to implement something like the DaysAgo Timer.
Or maybe find one of the USB Interface chips to build something fun like the USB Hampster Wheel that responds to your typing.
LED Temperature Thermometer Project
This LED temperature thermometer project will display the room temperature where it is placed using 10 LEDs, with each LED representing 2 degree Fahrenheit step, forming a bargraph display.
A group of us were interested in the Graffiti Research Lab’s Throwies and decided to try some for Fiesta in San Antonio. A throwie is an LED, small battery, and a strong rare earth magnet. The cost on all of these items is now low enough that you can make the throwies for under 50 cents each in quantity.
We started out the evening at La Tuna to assemble the throwies and discuss our plans. After building almost 200 throwies we started talking about where to toss them. At least a few of them went on the outside of La Tuna while we made up our minds. We all piled in the van and made our way to the Riverwalk.
At first we just experimented with lamp posts, street signs (most are aluminum) but we soon came to one of the tressel bridges over the Riverwalk. We used up about a third of them on the top of the bridge, handing some to passer-bys that looked interested. Many strangers joined in the fun by throwing ones we gave them and picking up fallen throwies. Everyone thought it was great fun and a cool idea.
Next we trapsed around the river where we tagged a number of fence posts, signs and various vendor and restaurant carts. The undersides of most bridges turned out to be too crowded to risk throwing things but we did manage to light up the beams under at least one bridge.
Before the night was out we returned to the original bridge to see how many LEDs had gone missing. Most of them were still there (the ones up high) so we handed out a few more and added more color to the bridge before heading back to La Tuna. We lit up the back wall at La Tuna with the remaining LEDs before calling it a night.
The whole evening was a lot more fun than I expected with much of the thrill of graffiti without the permanent damage that paint causes. The LEDs should shine for close to a week at which point we’ll go back and recover as many as we can to to be recycled and reused.
For some more information about Throwies check out these links:
http://www.instructables.com/
http://graffitiresearchlab.com/
http://www.makezine.com/
[Update:]
Another post about the evening here: http://sweaterproject.org/2006/04/24/concerning-throwies/
Another cool project that I’d like to attempt someday. An alternative to controlling one of these with a pic or gumstick might be a few parallel ports on an old PC.
The LED cube was a project started by Gene Foulk and I to create a large, animated, self contained visualization cube of LEDs, mostly for artistic purposes, but it also would have other uses.
Tutorial for LEDs and Transistors
Nice tutorial about LEDs and Transistors.
An LED is the device shown above. Besides red, they can also be yellow, green and blue. The letters LED stand for Light Emitting Diode. If you are unfamiliar with diodes, take a moment to review the components in the Basic Components Tutorial. The important thing to remember about diodes (including LEDs) is that current can only flow in one direction.
You can see some of the pictures here:
MAX756 DC-DC Step UP
I’ve built this for one of the LED projects I’m working on. Very good refresher on reading schematics and applying them to the real world. The power supply will provide 3.3V or 5V out with a minimum of 0.7V in. (Requires 1.1V to start.)
More info on the IC here:
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/1167
[Update: 2006/05/15]
Made the MAKE Blog today.
This is going to be another simple lamp, but with better power management and a different form. I’ve seen some “puck” shaped lights on the net, namely the Indium from Angus Noble that retails for about $80.
Altoids LED Lamp.
I’ve been interested in LED lamps for some time now, and finally bought a batch of bright white LEDs. I got these from LED supply. The LEDs run at 4.5V max at 20 mA and have a luminous intensity of 6400 mcd. They aren’t the brightest LEDs I could find on the net, but they are brighter than most, and the price isn’t too bad, $13.50 plus shipping for 10 of them. In contrast, Radio Shack wants over $5 each for their bright white LEDs (at about half the luminosity). LED Supply shipped two days after I ordered, and I received them by priority mail the next day, about 72 hours after placing my order.
I had a chat over IM with my father last night about the LED lamps, and he made a couple suggestions that helped with the design. I was originally going to hack up my halogen desk lamp, but decided against that since I sometimes need the intense white light it provides, like when I was building this lamp. He suggested using household copper wire and wrapping the leads around it. I still think that’s a good idea, and may pursue it for my next light, but I ended up using some 20 guage wire, twisted tightly for the stalk and an Altoids tin for the base.
