Author: Bryan Cockfield

1826 Articles

Long-Theorized GPS Weakness Exploited On Large Scale

June 23, 2026 by 37 Comments

GPS has become fairly common in our everyday lives, not only able to pinpoint our locations on Earth but also as an incredibly accurate timekeeping method. But since these satellites are around 20,000 km above Earth, the received signals on the surface of the planet can be incredibly weak. This makes them prone to jamming and spoofing, a weakness of the technology that has long been known. Although attempts to mitigate these problems have been ongoing, there has recently been a large-scale attempt to interfere with these signals that put all mitigation efforts to the test.

One proposed way to improve resilience is to supplement existing GNSS systems with low-Earth-orbit navigation satellites. In this example, a company called Xona is using a satellite called Pulsar-0 that operates in low-Earth orbit (LEO) and provides positioning and timing signals that are around 100 times stronger than standard signals from GPS/GNSS satellites. It is able to receive GPS signals as well, ensuring the two systems agree on one another. And, because Pulsar’s navigation signals originate from LEO and are much stronger than conventional GNSS signals, Xona expects them to be significantly more resistant to jamming.

Beyond geopolitics, spoofing GPS has some applications in finding legendaries in Pokemon Go as well as making it fairly trivial to steal GPS-guided drones.

Dynamic RAM From First Principles

June 22, 2026 by 25 Comments

Before the past year, many of us took computer memory for granted. It was one of the lower-cost parts of a PC build and was usually available in whatever quantity one desired. As its cost has skyrocketed, a lot of PC builders and other users of computers in general are taking a deeper look at memory, how much is really needed, and what its functions truly are. [Igor] is working on a drum sequencer project which needs a small amount of memory, and has built this dynamic RAM from discrete components.

The first video goes into the construction of the memory array and how its addressed. It’s only eight bytes total, and using fairly large electrolytic capacitors to store data means that a gigabyte of this memory would take up well over a thousand acres, but it’s still enough memory for [Igor]’s needs. In addition to the capacitor, each bit uses a pair of diodes to determine if a read or write is occuring, and a set of transistors on the read and write busses to perform those actions. Worth noting here is that dynamic RAM like this needs to be refreshed because the capacitors lose charge over time, but these large capacitors can hold charge sometimes overnight, as [Igor] has confirmed experimentally.

There’s a followup video to the construction of these modules as well, where [Igor] demonstrates a number of ways this module can be used, from controlling LED arrays, 7-segment displays, and then installs it into his drum machine. With 64 bits available it’s capable of creating up to eight beats with eight samples available per beat. Although there are complete machines available for all of this, we appreciate his goal of not buying any pre-manufactured hardware and instead constructing it all from the ground up. There are analog drum machine options available in this same style as well.

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Graphics Upgrade For Nintendo Entertainment System

June 22, 2026 by 22 Comments

Modern video game consoles rarely have expansion ports, but in the 80s and 90s it was practically guaranteed. With the speed that hardware was advancing it made sense to build in some way to upgrade a system’s capabilities throughout its lifespan. But while this gave us things like the Sega CD and N64 Expansion Pak, many ports ultimately went unused. Given this recent project from [decrazyo], one wonders if unused port on the bottom of the Nintendo Entertainment System could have been used to expand its graphical capabilities.

The basis of this upgrade is the fact that the Picture Processing Unit (PPU) on the NES has four pins that are grounded. These four pins tell the NES to display the background color if the pixel is transparent. Since they’re normally grounded, this means the NES can only display a limited background image, but there’s no reason these pins must be grounded. By using a second PPU configured to output graphics information and wiring it to these four pins on the first PPU, the NES can be given all kinds of new abilities, such as adding parallax effects to backgrounds, rendering more sprites, and showing more colors in the backgrounds.

Of course, the hardware requirements for this will require a donor NES to get the second PPU as well as the necessary memory chip for it, and we don’t recommend tearing apart perfectly good retro consoles for experimentation if it can be avoided. Presumably, you could use this open-source NES hardware alternative instead. But for those with the parts and the gumption, creating a demo or adding graphics features to homebrew games using this second graphics chip is within reach.

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PCBs Straight From The Magazine

June 19, 2026 by 32 Comments

It’s never been easier to get a printed circuit board made. In fact, almost every electronics video out on the internet will incessantly remind you of this fact now. But making a custom PCB wasn’t always as straightforward as sending a KiCad file to a board house. Many DIY methods involve harsh chemicals and tedious processes, but did have the potential benefit of taking much less time than waiting on boards to arrive in the mail. [Bettina Neumryr] is demonstrating one of these older methods, called the toner transfer method, using a circuit that was printed directly in an old magazine.

The first part of the toner transfer method is to create an image that can be printed. Since this circuit came from a magazine, it is first scanned in to a computer and imported into GIMP, where it can be scaled to match the size of the components and then sharpened to make a crisp print. With the image ready, it’s time to print the image onto some toner transfer paper, ensuring that the printer in question is a laser printer which actually uses toner. From there, a sheet of blank copper PCB is prepared and then the toner is transferred by heating, in this case using a laminator. After that its etched, removing all of the copper not protected by the toner, and then the toner itself can be removed which leaves behind the copper traces.

For those of you who were around when toner transfer was in vogue, this video might not have much value. But for anyone who can’t use a board manufacturer for whatever reason or is looking for alternatives, a modern video showing the method could be much more useful and have better context for beginners than videos made a decade or more ago now. Some of those older methods include similar processes using inkjet printers instead, but there are more modern DIY methods as well using lasers or CNC machines too.

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Solid-State Batteries Take To The Sky

June 17, 2026 by 13 Comments

There always seem to be a handful of revolutionary technologies perpetually out of reach: fusion energy, quantum computers, and full self-driving cars are always in this list, and it seems like there’s also some battery technology which will finally let us fully decouple from fossil fuels in there as well. Although lithium batteries have allowed some ground-based electric transportation, the energy density is still not enough to enable full electrification, especially for things like aircraft. Solid state batteries may be on the verge of changing some of this, though, and a team has recently put them to work in a test aircraft to help make some headway with this novel battery chemistry.

The main contributing factor of these batteries’ improved energy densities is the ability to use a solid lithium anode, which has much higher energy density than the graphite-based anodes in modern liquid electrolyte batteries. Solid state batteries also have improved safety, since the solid electrolyte is generally not flammable and the battery itself is less prone to thermal runaway. The tests in this aircraft, a modified motorized glider, bear this out as well. With a standard lithium ion pack the team was able to harness 250 Wh/kg and with their new solid state battery they managed 410 Wh/kg, which let them fly the craft up to 24,000 feet (7,315 m) with the help of some wing-mounted solar panels.

Of course, a motorized glider is a long way away from battery-powered commercial flights, but tests like this are an important step on the way to de-carbonizing one of the more impactful industries on the planet, as well as hopefully making it less expensive to operate aircraft in the way EVs are generally much cheaper to operate than their internal combustion equivalents. But the limiting factor to adopting solid state batteries isn’t going to be implementation but rather the discovery of a cost effective way to manufacture them at scale. It’s the same reason we haven’t seen mass adoption of things like algae-based biodiesel or economic carbon capture yet.

Security Camera Gets Several Defensive Upgrades

June 16, 2026 by 21 Comments

Ever since the early web, people have been streaming video with inexpensive webcams, and since the advent of the Raspberry Pi and its dedicated camera slot we’ve really seen how easy it can be to build security cameras or any other webcam and get it online quickly. But these cameras notably lack defensive capabilities if anyone tries to break into an area they shouldn’t be, and [John] added some features to this webcam to help defend his garage.

The webcam itself is a custom build, mounted on a custom-built tilt-and-pan mount that lets it freely rotate to view any location in the garage. Some custom software running on a Raspberry Pi lets it operate in autonomous mode or be controlled manually from an Android tablet. But for the defensive capabilities, it also carries a Nerf machine gun with a laser sight and spotlights which can all be controlled autonomously by the Raspberry Pi, including a computer vision system that lets it track various objects. While this is mostly a fun novelty for his security camera, the noise it makes might be enough to startle any would-be burglar.

[John] added a few other features to this build as well, including a speaker, which allows the system to be voice-controlled and to communicate back to the user. This lets him activate and deactivate the system using a verbal password. These types of Nerf guns are fairly popular for turrets as well, and some have practical uses as well like keeping cats from walking on the kitchen counters.

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Deltarune’s Tenna Brought To Life

June 3, 2026 by 1 Comment

For those who have never played the hit video games Undertale and Deltarune, the games are partially known for their interesting characters, many of which have eerie, surreal, and expressive designs. One of the more memorable characters from Deltarune is Tenna, a game show host of sorts whose distinguishing feature is an old television as a head, as well as a colorful suit. As a result he’s been the subject of a number of recreations by various cosplayers and makers like [BigRig Creates].

This version of the character was actually inspired by a previous build by [BunnyBii] which used an iPad as the interactive screen/face. Inside the television, though, the actual human found this to be front heavy and limiting in the ways that it could be used interactively, especially since the only way to see the outside world in this version was with a small endoscope and screen. [BigRig Creates]’s version builds on this idea but swaps out the iPad for a Raspberry Pi, allowing for much more customization, and uses a pair of Xreal glasses instead of a screen for the view of the outside world from in the television.

To get the whole costume together, the head is 3D printed with all of the electronics inside, and a game controller integrated into a handheld microphone controls the animations shown on the screen. A vibrant, custom-tailored suit with white gloves rounds out the ensemble, along with a pair of 3D-printed shoe covers since actual yellow shoes were a bit pricy. There were some interesting problems to solve along the way, specifically with regards to power management for all the electronics, but in the end it all seems to have come together quite well. [BigRig Creates] is no stranger to builds with unusual displays, though; one of our favorites was the world’s largest Nintendo 3DS.

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