Working all year long, herding elves and fabricating toys for all the good boys and girls; it takes dedication. It’s only natural that one could fall behind in beard care, right? This year, [Norbert Zare] saves Christmas with his beard-combing robot.
OK, this is much more of a shitty robot in the [Simone Giertz] school of wicked funny machines than it is a serious robotics project. But props to [Norbert] for completeness — the code that wiggles the two servos that get the job (almost) done is even posted up on GitHub.
We doubt that few of us ever thought that snow globes contain real snow, but now that we’ve seen a snow globe that makes its own snow, we have to admit the water-filled holiday decorating mainstay looks a little disappointing.
Like a lot of the Christmas decorations [Sean Hodgins] has come up with over the years, this self-frosting snowman is both clever in design and cute in execution. The working end is a piece of aluminum turned down into the classic snowman configuration; the lathe-less could probably do the same thing by sticking some ball bearings together with CA glue. Adorned with 3D-printed accessories, the sculpture sits on a pedestal of Peltier coolers, stacked on top of a big CPU cooler. Flanking the as-yet underdressed snowman is a pair of big power resistors, which serve as heating elements to fill the globe with vapor. [Sean]’s liquid of choice is isopropyl alcohol, and it seems to work very well as the figurine is quickly enrobed with frost.
The surprise in this age of ubiquitous microcontrollers is that this is not a smart device; instead it’s a single-purpose logic chip whose purpose is to step through a small ROM containing note values and durations, driving a frequency generator to produce the notes themselves. The frequency generator isn’t the divider chain from the RC oscillator that we might expect, instead it’s a shift register arrangement which saves on the transistor count.
Although the UM66 is a three-pin device, there are a few other pins on the die. These are likely to be for testing. As a 30+ year old product its design may be outdated in 2021, but it’s one of those chips that has survived without being superseded because it does its task without the need for improvement. So when you open a card and hear the tinny tones of a piezo speaker this holiday season, spare a thought for the ingenuity of the design behind the chip that makes it all possible.
The festive season is often as good a reason as any to get out the tools and whip up a fun little project. [Simon] wanted a little tchotchke to give out for the holidays, so they whipped up a Christmas tree PCB that’s actually Arduino-compatible.
It’s a forward-looking project, complete with USB-C connector, future-proofing it for some time until yet another connector standard comes along. When plugged in, like many similar projects, it blinks some APA102 LEDs in a festive way. The PCB joins in on the fun, with white silkscreen baubles augmented by golden ones created by gaps in the soldermask.
An ATTiny167 is the brains of the operation, using the Micronucleus bootloader in a similar configuration to the DigiSpark Pro development board. It relies on a bit-banged low-speed USB interface for programming, but the functionality is largely transparent to the end user. It can readily be programmed from within the Arduino IDE.
It’s not an advanced project by any means, but is a cute giveaway piece which can make a good impression in much the same way as a fancy PCB business card. It could also serve as an easy tool for introducing new makers to working with addressable LEDs. Meanwhile, if you’ve been cooking up your own holiday projects in the lab, don’t hesitate to drop us a line!
The festive season is upon us, and for Brits of a technical bent that means it’s time for the GCHQ Christmas Challenge. Sent out annually as part of the Christmas card from the UK’s intelligence centre, this is a chance for would-be spooks to pit their wits against some of the nation’s cleverest cryptologists whose work you’ll never have heard of.
This year the puzzle is aimed at those with a secondary school education, in the hope of fostering an interest in maths and science in younger people. It’s a series of puzzles of ascending difficulty, but don’t be lulled into a false sense of security by the earlier ones being easy, to complete the set will still require some brain power.
[Arnov] is trying to get into the holiday spirit and is doing so the way he knows how. He was thinking of some cool decorations for his Christmas tree and decided the best decorations are the ones you make yourself, so he made his own blinky Christmas tree ornament.
The famed “blinky circuit” is certainly one that we are no strangers to here at Hackaday. Some of our readers will be very pleased to see that he did in fact use a 555 timer and not an Arduino. The 555 timer is wired to drive the clock pin of the CD4017 decade counter and the outputs of the decade counter are wired to the LEDs. The LEDs are lit up sequentially upon each low to high transition of the clock pulse though you may try getting creative with your LED wiring scheme to achieve different blinking effects.
What readers might really take away from this build is [Arnov] detailing how to import images into his CAD tool of choice, OrCAD in his case. We know that can be a bit tricky sometimes. Finally, we love that this project doubles as PCB art and a soldering challenge. It would definitely make for a good demo project at your next beginner soldering workshop.