‘Tis the season for gift giving, and what better to give than a newfound love for hacking, soldering, and blinkenlights? In order to spread cheer and education at the local hackerspace, [Tom Goff] created this festive tree circuit board that can either sit in a stand to be admired, or worn as jewelry. The resistors are even designed to look like candy canes hanging from the boughs.

The brains of this festive little tree is an ATmega328P, which you probably recognize as the microcontroller that powers the Arduino Uno. Although this circuit has none of the extra bits you’d find on an Uno, not even a crystal oscillator, it can still be programmed with Arduino and use the 8 MHz internal clock.

[Tom] has provided good, thorough instructions, especially for the sticky bit of setting up the IDE to program using the 8 MHz internal clock. So even if you’re nowhere near Norwich Hackerspace, you can join in the fun. Be sure to check out the video after the break, wherein [Tom] walks through designing the PCB using Inkscape and Fritzing.

Want to whip up a little something for the hackerspace wall? Check out this Sierpinski Christmas tree.

It’s really quite unfortunate that Hackaday/Supplyframe employees and their families are not allowed to place in the 2023 Halloween Hackfest, because our own [Tom Nardi] has thrown down a costume gauntlet with his kids’ proton pack conversion.

Starting with an inert off-the-shelf toy from 2021, [Tom] set out to make the thing more awesome in every way possible. For one thing, it’s blue, and outside of the short-lived animated series The Real Ghostbusters, who ever heard of a blue proton pack? So one major change was to paint it matte black and age it with the old silver rub ‘n buff technique. And of course, add all the necessary stickers.

[Tom] added plenty of blinkenlights, all running off of an Arduino Nano clone and a pair of 18650s. He got lucky with the whole power cell thing, because an 8 x 5050 RGB LED stick fits there perfectly and looks great behind a PETG diffusing lens. He also drilled out and lit up the cyclotron, because what’s a proton pack without that? There’s even a 7-segment LED voltmeter so Dad can check the power level throughout the night.

Finally, he had to do a bit of engineering to make the thing actually wearable by his daughter. A frame made of square aluminium tubing adds strength, and a new pair of padded straps make it comfortable. Be sure to check it out in action after the break.

What’s a Ghostbusters costume without a PKE meter? 

What could be better than a Halloween decoration? Something more perennial, or even something that could also be found in a classroom or lab. Something like [Markus Bindhammer]’s spooky muscle-brain interface. It was inspired by a series called “Tales From the Loop” in which a character’s muscle electrical activity is measured in preparation to adjust his prosthetic hand.

Essentially, it does what you think it does: attach the sensors to your muscles, move them around, and watch the brain light up. [Markus] started with a children’s learning kit that involves molding the brain and discs out of red rubbery goop, the vertebrae out of plaster, and then assembling the whole thing.

Instead, [Markus] molded the brain and vertebrae in two-part silicone for durability, and used two-component colored epoxy for the discs.

As the inspiring series is set in the 80s (we assume the brown, dingy 80s and not the fun, neon 80s), [Markus] gave the enclosure/stand an appropriate color scheme. Inside that box there’s an Arduino Pro Micro, a Grove EMG detector, and a mini step-up converter module. And of course, under the brain, there’s a NeoPixel ring. Don’t miss the build and demo video after the break.

There are a ton of things you can do with blinkenlights for Halloween. How about a light-up candy slide, or a bucket that seems them coming?

Even though it seems the worst of COVID has passed, October generally kicks off cold and flu season, so why not continue to pass out Halloween treats in a socially-distanced fashion?

That is, of course the idea behind [Gord Payne]’s Halloween Treat Trough of Terror. Lay a treat at the top of the trough and it will activate the LED strips that follow the treat down to the end, as well as some spooky sounds. The treat in question is detected by an SR-04 ultrasonic distance sensor connected to an Arduino Nano.

All in all this was a highly successful build as far as neighborhood entertainment value goes. Toddlers stared in awe at the blinkenlights, teenagers proclaimed it ‘sick’, and we can only assume that the adults were likely happy to see something aimed at kids that’s not scary.

[Gord] has a nice how-to if you want to build your own, and of course, the Arduino sketch is available. Be sure to check it out in action after the break.

Don’t have room to build a treat slide? Here’s a socially-distanced dispenser that lets them stomp a giant button.

Yet another Day of the Chocolate Bunnies has passed by, and what did you do to mark the occasion? You likely kicked back and relaxed, surrounded by whatever you gave up for Lent, but good for you if you mixed chocolate and electronics like [Repeated Failure] did. They created a completely edible chocolate Easter bunny that screams when bitten.

So obviously, the hardest part is figuring out something to build the circuit with that is both conductive and safe to eat. [Repeated Failure] spent a lot of time with carbon oleogel paste, which is made from natural oils and waxes. Not only was it less conductive than [Repeated Failure]’s skin, it came out pitch black and tasted like nothing, which kind of a bonus, when you think about it.

Then came the cake paint, which [Repeated Failure] laced with trace amounts of silver powder. While that worked somewhat better, a successful circuit would have likely required near-fatal amounts of the stuff. Yikes!

The winner turned out to be edible silver leaf, which is like gold leaf but cheaper. Ever had Goldschläger? Gold leaf is what’s suspended inside. The really nice thing about silver leaf is that it comes in thin sheets and can easily be cut into circuit traces with scissors and connected to I/O pins with copper tape. Be sure to check it out after the break, including [Repeated Failure]’s friend’s reaction to innocently biting the chocolate bunny’s ears off, as one tends to do first.

Think you’d rather hear plants giggle? Sure, it sounds cute, but it’s actually kind of creepy.

Who says it’s too early to get in the holiday spirit? We say it’s not. After all, people need time to get in the spirit before it comes and goes. And what better way to count down the days until Christmas than an electronic Advent calendar?

[Tom Goff]’s kids had some pretty cool ideas for building a decoration, like a musical, lighted sleigh complete with robotic Santa Claus. While that’s a little much to pull off for this year, they did salvage the music and lights part for their Hackvent calendar.

There are 24 small LEDs for December 1st through the 24th, and a big white star for December 25th. Each day, the kids just push the button and the day’s LED lights up. On the big day, all the small lights cascade off and the white one lights up, then it plays Jingle Bells through a sound playback module.

Each LED is connected directly to an input on an Arduino Mega. While there are several ways of lighting up 25 LEDs, this one is pretty kid-friendly. We think the coolest part of this build is that [Tom] and the kids did it old school, with nails hammered into the laser-cut plywood and used as connection terminals. Be sure to check it out in action after the break.

The more time you have, the more you can put into your Advent calendar build. Like chocolates, for instance.

The Jack o’ Lantern is a fun Halloween tradition, though one that does come with a few risks. It’s pretty easy to slice off a bit of finger when carving a stiff pumpkin, and candles draw more enmity from fire crews than most household items. For the electronics beginner looking for a learning project, [Oyvind’s] build might be a nice safe bet.

The build starts with a 3D-printed pumpkin figurine with a suitably spooky face, though [Oyvind] notes there’s nothing stopping this project from being executed with a real orange gourd instead. Inside, an Arduino is hooked up to a trio of orange LEDs. They’re attached to PWM pins and each is given a random brightness value at regular intervals to create a pleasant flickering effect.

It’s a very simple project, but it’s also the kind of thing that’s perfect for introducing new people into the world of electronics. There’s little to get wrong, and mistakes aren’t costly, making it an ideal project for beginners. From there, the sky really is the limit! Video after the break.

Unless you have an incredibly well-stocked parts bin, it’s probably too late to build these spooky animated eyes to scare off the neighborhood kiddies this year. But next year…

It’s pretty clear that Halloween decorating has gone over the top recently. It may not be as extreme as some Christmas displays, but plenty of folks like to up the scare-factor, and [wermy] seems to number himself among those with the spirit of the season. Like Christmas lights, these eyes are deployed as a string, but rather than just blink lights, they blink creepy eyes from various kinds of creatures. The eyes are displayed on individual backlit TFT-LCD displays housed in 3D-printed enclosures. Two pairs of eyes can be driven by the SPI interface of one ItsyBitsy M0 Express; driving more displays works, but the frame rate drops to an unacceptable level if you stretch it too far. Strung together on scraps of black ethernet cable, the peepers can live in the shrubs next to the front door or lining the walk, and with surprisingly modest power needs, you’ll get a full night of frights from a USB battery bank.

We like the look of these, and maybe we’ll do something about it next year. If you’re still in the mood to scare and don’t have the time for animated eyes this year, try these simple Arduino blinky eyes for a quick hit.

Thanks to [baldpower] for the treat. No tricks.

Chances are good that a fair number of us have been roped into “one of those” projects before. You know the type: vague specs, limited budget, and of course they need it yesterday. But you know 3D-printers and Raspberduinos and whatnot; surely you can wizard something together quickly. Pretty please?

He might not have been quite that constrained, but when [Sean Hodgins] got tapped to help a friend out with an unusual project, rapid prototyping skills helped him create this GPS-enabled faux-walkie talkie audio player. It’s an unusual device with an unusual purpose: a comedic walking tour of Vancouver “haunted houses” where his friend’s funny ghost stories are prompted by location. The hardware to support this is based around [Sean]’s useful HCC module, an Arduino-compatible development board. With a GPS module for localization and a VS1053 codec, SD card reader, and a small power amp for the audio end, the device can recognize when the user is within 50 meters of a location and play the right audio clip. The housing is a 3D-printed replica of an old toy walkie-talkie, complete with non-functional rubber ducky antenna.

[Sean]’s build looks great and does the job, although we don’t get to hear any of the funny stuff in the video below; guess we’ll have to head up to BC for that. That it only took two weeks start to finish is impressive, but watch out – once they know you’re a wizard, they’ll keep coming back.

Halloween is a great holiday for hacks, bringing out the creativity in even the most curmudgeonly wielder of a soldering iron. [tdragger] was looking to have some good old fashioned Halloween fun, and got to thinking – putting together this great Spooky Eyes build in their attic window.

The effect itself is simple – just two glowing orange LEDs spaced the right distance apart, placed in the highest window in the house. As every young child knows, the attic is almost the spookiest room in the house, second only to the basement.

Various effects were programmed in to the Arduino running the show, like breathing and blinking effects, to give that frightful character. For maintenance and programming purposes, [tdragger] wanted to have the Arduino remotely mounted, and searched for a solution. Rather than leaning on a wireless setup or something modern and off-the-shelf, instead some old RJ11 telephone extension cables were pressed into service. These allowed the eyes to be placed in the window, allowing the Arduino to be placed in a more accessible location.

It’s a basic project, but one that has a good fun factor. Sometimes it’s good to use what you’ve got to hand, so that the buzz of enjoyment isn’t dampened by the long wait for shipping. For something bigger, check out this giant staring eyeball.