Pinball machines have something for everyone. They’re engaging, fast-paced games available in a variety of sizes and difficulties, and legend has it that they can be played even while deaf and blind. Wizardry aside, pinball machines have a lot to offer those of us around here as well, as they’re a complex mix of analog and digital components, games, computers, and artistry. [Daniele Tartaglia] is showing off every one of his skills to build a tabletop pinball machine completely from the ground up.

This is the latest in a series of videos documenting [Daniele]’s project, so he already has the general arrangement of the game set up. He has some improved ball-counting devices to enhance the game’s ability to keep track of ball position. [Daniele] also builds a few chutes and chimneys for the ball to pass outside of the play field. Next up are flippers and some of the bumpers.  The video is rounded out with conductive targets built completely from scratch using metal zip ties. With a machine as complex as this, there are many points during the build where he has to stop and redesign parts. Prototyping as he goes, [Daniele] adds to the distinctive flair of this unique game.

This build truly puts every tool in [Daniele]’s toolbox to work, from a laser cutter, lathe, and 3D printer to various microcontrollers, solenoids, and electronics. He seamlessly blends the analog world of steel ball bearings and rubber bumpers with the digital world of scoring, automation, lighting, and sound. Pinball machines are experiencing a bit of a resurgence, meaning many of the classic tables are expensive collector’s items. If you want to build your own, we featured a great resource for others like [Daniele] who want to build one of these intricate machines themselves.

Thanks to [Aaron] for the tip!

Halloween is about tricks and treats, but who wouldn’t fancy a bit to drink with that? [John Sutley] decided to complete his Halloween party with a drink dispenser looking as though it was dumped by a backstreet laboratory. It’s not only an impressive looking separating funnel, it even runs on an Arduino. The setup combines lab glassware, servo motors, and an industrial control panel straight from a process plant.

The power management appeared the most challenging part. The three servos drew more current than one Arduino could handle. [John] overcame voltage sag, brownouts, and ghostly resets. A healthy 1000 µF capacitor across the 5-volt rail fixed it. With a bit of PWM control and some C++, [John] managed to finish up his interactive bar system where guests could seal their own doom by pressing simple buttons.

This combines the thrill of Halloween with ‘the ghost in the machine’. Going past the question whether you should ever drink from a test tube – what color would you pick? Lingonberry juice or aqua regia, who could tell? From this video, we wouldn’t trust the bartender on it – but build it yourself and see what it brings you!

If you’re blessed with high water pressure at home, you probably love how it helps blast grime from your dishes and provides a pleasant washing experience. However, it can also cause a wonderful mess when that water splashes all over your countertops. [vgmllr] has whipped up a simple solution to this problem by installing an automatic splash guard.

The concept is simple enough—install a pair of flat guards that raise up when the sink is running, in order to stop water getting everywhere. To achieve this, [vgmllr] grabbed an Arduino, and hooked it up to a piezo element, which acts as a water sensor.

The piezo is attached to the bottom of the sink, and effectively acts as a microphone, hooked up to one of the Arduino’s analog-to-digital pins. When water flow is detected, the Arduino commands two servos to raise a pair of 3D printed arms that run up and down the outside of the sink. Each arm is fitted with magnets, which mate with another pair of magnets on the splash shields inside the sink. When the arms go up, the splash shields go up, and when the arms go down, the splash shields go down.

It’s an ingenious design, mostly because the installation is so clean and seamless. By using magnets to move the splash shields, [vgmllr] eliminated any need to drill through the sink, or deal with any pesky seals or potential water leaks. Plus, if the splash shields are getting in the way of something, they can easily be popped off without having to disassemble the entire mechanism.

It’s a tidy little build, both practical and well-engineered. It’s not as advanced as other kitchen automations we’ve seen before, but it’s elegant in its simple utility.

Generally people equate the Arduino hardware platforms with MCU-centric options that are great for things like low-powered embedded computing, but less for running desktop operating systems. This looks about to change with the Arduino Uno Q, which keeps the familiar Uno formfactor, but features both a single-core Cortex-M33 STM32U575 MCU and a quad-core Cortex-A53 Qualcomm Dragonwing QRB2210 SoC.

According to the store page the board will ship starting October 24, with the price being $44 USD. This gets you a board with the aforementioned SoC and MCU, as well as 2 GB of LPDDR4 and 16 GB of eMMC. There’s also a WiFi and Bluetooth module present, which can be used with whatever OS you decide to install on the Qualcomm SoC.

This new product comes right on the heels of Arduino being acquired by Qualcomm. Whether the Uno Q is a worthy purchase mostly depends on what you intend to use the board for, with the SoC’s I/O going via a single USB-C connector which is also used for its power supply. This means that a USB-C expansion hub is basically required if you want to have video output, additional USB connectors, etc. If you wish to run a headless OS install this would of course be much less of a concern.

What does one do with old circuit boards and projects? Throwing them out doesn’t feel right, but storage space is at a premium for most of us. [Gregory Charvat] suggests doing what he did: combining them all into a wall-mountable panel in order to memorialize them, creating a functional digital clock in the process. As a side benefit, it frees up storage space!

Memorializing and honoring his old hardware is a journey that involved more than just gluing components to a panel and hanging it on the wall. [Gregory] went through his old projects one by one, doing repairs where necessary and modifying as required to ensure that each unit could power up, and did something once it did. Composition-wise, earlier projects (some from childhood) are mounted near the bottom. The higher up on the panel, the more recent the project.

As mentioned, the whole panel is more than just a collage of vintage hardware — it functions as a digital clock, complete with seven-segment LED displays and a sheet metal panel festooned with salvaged controls. Behind it all, an Arduino MEGA takes care of running the show.

Creating it was clearly a nostalgic journey for [Gregory], resulting in a piece that celebrates and showcases his hardware work into something functional that seems to have a life of its own. You can get a closer look in the video embedded below the page break.

This really seems like a rewarding way to memorialize one’s old projects, and maybe even help let go of unfinished ones.

And of course, we’re also a fan of the way it frees up space. After all, many of us do not thrive in clutter and our own [Gerrit Coetzee] has some guidance and advice on controlling it.

As we all look across a sea of lifeless, nearly identically-styled consumer goods, a few of us have become nostalgic for a time when products like stereo equipment, phones, appliances, homes, cars, and furniture didn’t all look indistinguishable. Computers suffered a similar fate, with nearly everything designed to be flat and minimalist with very little character. To be sure there are plenty of retro computing projects to recapture nostalgia, but to get useful, modern hardware in a fun, retro-themed case check out this desktop build from [Mar] that hides a few unique extras.

The PC itself is a modern build with an up-to-date operating system, but hidden in a 386-era case with early-90s styling. The real gem of this build though is the floppy disk drive, which looks unaltered on the surface. But its core functionality has been removed and in its place an Arduino sits, looking for NFC devices. The floppy disks similarly had NFC tags installed so that when they interact with the Arduino,it can send a command to the computer to launch a corresponding game. To the user it looks as though the game loads from a floppy disk, much like it would have in the 90s albeit with much more speed and much less noise.

Modern industrial design is something that we’ve generally bemoaned as of late, and it’s great to see some of us rebelling by building unique machines like this, not to mention repurposing hardware like floppy drives for fun new uses (which [Mar] has also open-sourced on a GitHub page). It’s not the first build to toss modern hardware in a cool PC case from days of yore, either. This Hot Wheels desktop is one of our favorites.

Humanity pretty much has Pi figured out at this point. We’ve calculated it many times over and are confident about what it is down to many, many decimal places. However, if you fancy estimating it with some electronic assistance, you might find this project from [Roni Bandini] interesting.

[Roni] programmed an Arduino Nano R4 to estimate Pi using the Monte Carlo method. For this specific case, it involves drawing a circle inscribed inside a square. Points are then randomly scattered inside the square, and checked to see if they lie inside or outside the circle based on their position and distance of the circle’s outline from the center point of the square. By taking the ratio of the points inside the circle to the total number of points, you get an approximation of the ratio of the square and circle’s areas, which is equal to Pi/4. Thus, multiply the ratio by 4, and you’ve got your approximation of Pi.

[Roni] coded a program to run the Monte Carlo simulation on the Arduino Nano R4, taking advantage of the mathematical benefits of its onboard Floating Point Unit. It generates 100 new samples for the Monte Carlo approximation every second, improving the estimation of pi as it goes. It then displays the result on a 7-segment display, and beeps as it goes. [Roni] readily admits the project is a little too close in appearance to a classic Hollywood bomb.

We’ve seen some other neat Pi-calculating projects before, too.

For those living in the continental US who, for whatever reason, don’t have access to an NTP server or a GPS device, the next best way to make sure the correct time is known is with the WWVB radio signal. Transmitting out of Colorado, the 60-bit 1 Hz signal reaches all 48 states in the low-frequency band and is a great way to get a clock within a few hundred nanoseconds of the official time. But in high noise situations, particularly on the coasts or in populated areas these radio-based clocks might miss some of the updates. To keep that from happening [Mike] built a repeater for this radio signal.

The repeater works by offloading most of the radio components to an Arduino. The microcontroller listens to the WWVB signal and re-transmits it at a lower power to the immediate area, in this case no further than a few inches away or enough to synchronize a few wristwatches. But it has a much better antenna for listening to WWVB so this eliminates the (admittedly uncommon) problem of [Mike]’s watches not synchronizing at least once per day. WWVB broadcasts a PWM signal which is easy for an Arduino to duplicate, but this one needed help from a DRV8833 amplifier to generate a meaningfully strong radio signal.

Although there have been other similar projects oriented around the WWVB signal, [Mike]’s goal for this was to improve the range of these projects so it could sync more than a single timekeeping device at a time as well as using parts which are more readily available and which have a higher ease of use. We’d say he’s done a pretty good job here, and his build instructions cover almost everything even the most beginner breadboarders would need to know to duplicate it on their own.

As Earthlings, most of us don’t spend a lot of extra time thinking about the gravity on our home planet. Instead, we go about our days only occasionally dropping things or tripping over furniture but largely attending to other matters of more consequence. When humans visit other worlds, though, there’s a lot more consideration of the gravity and its effects on how humans live and many different ways of training for going to places like the Moon or Mars. This gravity simulator, for example, lets anyone experience what it would be like to balance an object anywhere with different gravity from Earth’s.

The simulator itself largely consists of a row of about 60 NeoPixels, spread out in a line along a length of lightweight PVC pipe. They’re controlled by an Arduino Nano which has a built-in inertial measurement unit, allowing it to sense the angle the pipe is being held at as well as making determinations about its movement. A set of LEDs on the NeoPixel strip is illuminated, which simulates a ball being balanced on this pipe, and motion one way or the other will allow the ball to travel back and forth along its length. With the Earth gravity setting this is fairly intuitive but when the gravity simulation is turned up for heavier planets or turned down for lighter ones the experience changes dramatically. Most of the video explains the math behind determining the effects of a rolling ball in each of these environments, which is worth taking a look at on its own.

While the device obviously can’t change the mass or the force of gravity by pressing a button, it’s a unique way to experience and feel what a small part of existence on another world might be like. With enough budget available there are certainly other ways of providing training for other amounts of gravity like parabolic flights or buoyancy tanks, although one of the other more affordable ways of doing this for laypeople is this low-gravity acrobatic device.

Here’s a fun project. Over on their YouTube page [Urban Circles] introduces Project Scribe.

The idea behind this project is that you can print out little life “receipts”. Notes, jokes, thoughts, anecdotes, memories. These little paper mementos have a physical reality that goes beyond their informational content. You can cut them up, organize them, scribble on them, highlight them, stick them on the wall, or in a scrapbook. The whole idea of the project is to help you make easier and better decisions every day by nudging you in the direction of being more mindful of where you’ve been and where you’re going.

The project is well documented on its GitHub page. The heart of the project is a thermal printer. These are the things that print the receipts you get from the store. You may need to conduct some research to find the best thermal paper to use; there are some hints and tips on this topic in the documentation. In addition to the thermal printer is a pretty stand to hold it and an Arduino board to drive it. Firmware for the Arduino is provided which will serve a basic web interface via WiFi.

If you build one, we’d love to hear how it goes. If it doesn’t work out, you can always fall back to using the thermal printer to level up your Dungeons and Dragons game.

Thanks to [Brittany L] for writing in about this one.