Got a bag of LEDs handy? Why not build a display with them? We’ve seen a lot of clocks that make use of LED modules but soldering your own is a fun pastime. [Vadim Suhovatih] did just that using 130 LEDs to build this clock. Each segment of the 7-segment digits consists of three LEDs in parallel which are switched by some 2N4401 transistors. An ATmega328 in the form of an Arduino controls the device with the aid of a DS1307 real-time clock for timekeeping and a 4017 decade counter to assist with scanning the display. Check out the demo after the break.
LED Hacks1886 Articles
Switchmode LED Flashlight Upgrade
When [Neelandan]’s cheap flashlight’s internal rechargeable battery died, he scrounged for a replacement. Ultimately, the brightness of the light suffered with his new battery, taken from an old cell phone since he had dropped the voltage a bit. Upon inspection he saw that he would have to swap the individual resistors for each lamp to get the desired brightness again. This wasn’t really acceptable as he would have to repeat the process if he used another re-purposed battery with different specs. Instead, he added a new circuit to supply constant brightness until the voltage drops below 2.7 volts. We love to see hardware resurrected, even if it is just a cheap LED flashlight.
May The Phorse Be With You
The PhorsePOV by [Julian Skidmore] almost slipped by, but we thought it was a nice easy hack for your Memorial Monday. The gadget uses an ATTINY25 to drive 6 LEDs aren’t standard characters 7 units high? Which when waved in the air produces a readable message. What we were really interested in is the use of a single button for text entry, called Phorse code, or an “easier to learn and remember” version of Morse code. While it seemed silly at first, most of us here could enter messages within a few minutes of trying.
32 LED POV Globe
[youtube=http://www.youtube.com/watch?v=bt1UEGD3BDk]
Here’s a slick version of a POV globe(google translated). Created by [Riko], this globe has 32 LEDs and is powered by a rotating coil. The layout looks fairly solid in operation, with the POV effect showing up very nicely on camera. You can get the schematics and source code from the project page.
We found this project, just like the previous fantastic LED globe on HackedGadgets.com. Apparently someone linked to this project in the comments. That is fantastic, that is what the comments should be for. Please help keep our comments polite and helpful as well, even if you are just linking to a project that you think is better.
POV LED Sphere
[youtube=http://www.youtube.com/watch?v=VF2dI7RiMVQ]
[Csaba Bleuer] has built this really nice POV LED sphere. Looking at the hand drawn schematic, it appears that he’s using an Atmega8 as the core. The resolution is pretty decent, and even shows fairly well on camera despite the refresh issues. Although much cleaner, it looks like a similar implementation to this one that we covered back in october of last year. He’s still got some polishing to do to match “the orb” though.
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…
Biosphere Lighting
Sometimes, sitting in a windowless office can drive you crazy. Adding a little bit of life and color can really help. [Gripen40k] did this by building a biosphere. He didn’t have any windows though, so he made an LED light on a PIC based timer. What is interesting is what he did with a thermistor. The Cree LED bulb that he salvaged was going to be submerged in the water, so he had to do some workarounds to keep from over heating the biosphere. Read the project log for more details.