[James] was wandering around Walgreens after Christmas and found something very interesting – RGB LED Christmas lights that were individually addressable. At $6.50 for a strand of 15 lights, he just had to buy a few and figure out the control protocol. After all, who can turn down a big, cheap, controllable RGB LED strip?
The packaging for these lights – apparently manufactured by BriteStar – includes a ‘try me’ button that cycles through different light patterns. This button is what initially tipped [James] off to the fact the lights on this strand could be individually controllable. Opening up one of the lights, he found exactly what he wanted: an epoxy blob, two wires for power, and three wires for the signaling.
After checking out this light with a scope and logic analyzer, [James] realized there was a very, very simple protocol going on. Essentially, the entire string functioned as a gigantic shift register, taking the values for one light and pushing it down the string. In looking at the protocol, [James] also discovered] these lights support 16 levels of brightness. Yep, RGB LED Christmas Lights with PWM for under $7. Can’t beat that.
[James] wrote an Arduino library to control these strings and put it up on Github. While your local Walgreens has probably already hidden these lights away in the back of the store, it might be worth asking around to see if they have any left.
What good is a fiber optic self-lighting Christmas tree if it flashes so fast it will put you into an epileptic attack? The answer is “Not very good”, if you ask [Mads Nielsen] a.k.a [EcProjects]. So [EcProjects ] started a little project to slow the Christmas tree’s blinkyness down to a more reasonable rate. The task didn’t seem too difficult at first but turned into a quality tutorial building a variable frequency H-bridge motor control.
After opening the base of the tree [EcProjects] found a 12 volt AC geared synchronous motor turning a multi colored translucent plastic disk. A bright spotlight was shining upwards through the turning disk into the ends of hundreds of small fiber optics. This mechanism dumps loads of multi colored light out the ends of the fibers at the tips of the Christmas tree branches as the disk turns.
His goal was to slow down the motor; however, the rotation was based on the 50 Hz mains signal. In order to continue using this motor a lower frequency AC power source was needed. What follows in the video is an excellent lesson on how an AC synchronous motor works plus how to build a variable frequency control and H-bridge using some transistors, resistors and CMOS 4069 inverter chip.
In the end the frequency drive could only be lowered to about 30 Hz before the synchronous motor would stall and reverse using his design. [EcProjects] was bold enough to include several fails which always provides more opportunity for learning and is greatly appreciated.
If you believe you have a better solution please share your idea in the comments. I’m sure the first proposal will include an Arduino and servo modified for continuous rotation, but any solutions would be fascinating including modifications to his design. You can join us after the break to watch the video.
Continue reading “Hacking a Christmas Tree for Less Blinkyness”
It’s Christmas time. You have a string of 50 individually addressable RGB LEDs, what would you do? Well, [Barney] decided to try something different. He’s made a Christmas tree that reflects Twitter’s current sentiments about the holiday.
Wait, what? We admit, it’s a kind of weird concept, but the software behind it is pretty cool. As it turns out Stanford University’s Natural Language Processing Group released the source code for their sentiment analyzer. Unlike a normal sentiment analyzer which assigns points to positive words and negative points for negative words, this one actually uses a deep learning model which builds up a representation of entire sentences based on their structure — only problem? It was designed and trained to analyze movie reviews, not Christmas tweets.
Regardless, it still does the trick (kind of), but, it’s pretty slow. [Barney] has his fastest computer running four instances of the analyzer, which pulls Christmas tweets that have been sorted by the Twitter API — it then analyzes them, assigns the sentiment, and places them in a second queue. He’s using beanstalkd for the queuing and a Raspberry Pi to control the lights. The result is a pretty light display whose colors represent the sentiments of incoming tweets — it’s hard to say if it’s actually successful in reflecting the opinion of the tweets, but it’s a pretty cool concept.
Stick around after the break to see the Christmas Tweet Analyzing Tree in action — say that 5 times fast!
Continue reading “Christmas Tree Analyzes Your Tweets”
If you’re looking for a last-minute Christmas present, you probably won’t have enough time to reproduce [Helmar’s] candle-powered Christmas card. He’s been working on it for a few years now, since his first prototype in 2010. Though he pieced together the original card with parts lying around his workshop, the most recent iteration looks like it belongs on the shelf in a store.
We last saw [Helmar’s] work two years ago, when he shared his Full Color Laser TV. This project is a bit more compact: the circuitry was printed with conductive ink on the cardstock, and all the required components are held together by conductive adhesive. To power the electronics, he decided against a battery and instead chose to embed a solar cell on the inside of the card. Placing a lit candle inside the open card provides enough juice for the exterior of the card to shine.
You can see a video of both the current and prototype versions of [Helmar’s] cards after the break.
Continue reading “CartoLucci: A Candle-Powered Christmas Card”
Fubarino Contest entries are starting to roll in at a faster rate. If you’re working on one you only have a few hours left! Submissions are due before 12:00am Pacific Time! This bit of inspiration is a two-fer. Both entries decided to use Morse Code to spell out the Hackaday URL.
First up, [Tariq] is getting into electronic design because his friend’s 8-year-old son [Yago] is really interested in Math and Science. The device he was working on is a little portable Morse Code message flasher (don’t miss part 2). The idea is that [Yago] can carry it around and pretend it’s a spy device containing a secret message. It might as well be since your average Joe probably wouldn’t notice the irregular flashing and if they did they wouldn’t be able to decode it without some help. The device is built around an ATtiny85. Normally it displays a Christmas greeting for [Yago]. But at the end of the cycle, or at power-up, it flashes the Hackaday URL at an extreme rate. Can anyone actually decode this without putting it on a logic analyzer?
The second offering is in the form of a blinky Christmas tree. [Jim] built the Arduino-compatible ornament for the holidays. It does a great job of flashing a bunch of different patterns, and it wasn’t too much work for him to make it flash the URL.
This is an entry in the Fubarino Contest. Submit your entry before 12/19/13 for a chance at one of the 20 Fubarino SD boards which Microchip has put up as prizes!
As [Medhi] was setting up his Christmas tree, he found a string with a few broken lights. Because he’d bought a cheap string of lights wired in series, of course one bulb was burnt out, rendering the entire string useless. His original game plan was to search through the entire strand for the broken bulb, but that’s the easy way out. His backup plan was to zap the broken bulb out of the string. After a few hours of figuring out what that meant, he came up with a way to fix a broken string of lights.
When a bulb burns out, the filament breaks creating an
air argon gap between the two electrodes. By sending a huge voltage down the string, it should fire an arc through that gap, illuminating the burnt-out bulb for a brief time.
Experiments with socks and low humidity commenced, but it wasn’t until [Medhi] stuck his finger in a lighter that he found a better source of high voltage sparks. [Mr. Brows] connected the piezoelectric element to the plugs on his string of lights and… nothing happened. At least until he plugged the lights back in. Then, strangely, they worked. The reddit thread for the video says this behavior is due to an anti-fuse built into the bulb. When enough voltage goes through this anti-fuse, a thin sheet of insulator breaks down and allows dead bulbs to short themselves.
Hackaday head honcho [Mike] just got this method of finding dead Christmas lights to work, replacing 14 bulbs in a string of 100 lights. This leads us to an interesting question: why isn’t this simple method of fixing a string of Christmas lights common knowledge? You would think something this useful wouldn’t be introduced to the world via a YouTube video where someone repeatedly burns and shocks himself. You can, of course, buy something that does the same thing, but this is far too simple of a solution for a classic problem to pass under our noses for this long.
Continue reading “Fixing Christmas Lights And Shocking Yourself Silly”
What happens when you put a few geeks in a room with a curtain rod, 240 Nespresso tubes, some planks, some tape, fairy lights, and a Raspberry Pi? Well, apparently this!
There’s not too much information on how they made it, but there is a pretty extensive gallery of photos. When we consider how much packaging we waste, it’s nice to see some being reused for a project, at least temporarily! The Nespresso tubes are pretty nice looking which certainly lends itself to this project, but our real question is who drank all the coffee…
The LED fairy lights are voice controlled using a Raspberry Pi model B, nothing too fancy, but a nice added affect. Check out the video after the break — the voice commands are in French though!
Continue reading “Inverted Christmas Tree Made of Nespresso Tubes”