Mysterious Files PH

Usually, the name ‘Famicom’ and the associated Nintendo Entertainment System (NES) don’t exactly bring to mind downloadable content and online services. However, at least in Japan, a modem add-on for the Famicom offered those features. Released in 1988, the Family Computer Network System (FCNS) offered all that using its modem to dial into Nintendo’s servers. Recently, [Throaty Mumbo] got his mitts on one of these units to try and see what you can still do with it in 2026.

Although only mildly successful in the Japanese market, Nintendo still sold 130,000 of these modem add-ons, with tens of thousands of users for the stock brokering, banking, and Super Mario Club services offered. The experiences with the FCNS would form the foundation for Nintendo’s Satellaview for the Super Famicom and from there into today’s Nintendo Online offerings.

Of course, the main challenge with reviving the FCNS in 2026 is that the remote servers were turned off decades ago, along with the minor detail that to do anything with it you need to insert a special card. This was missing in the used version that [Throaty Mumbo] bought, but fortunately he got a workable Super Mario Club card. The next struggle? He doesn’t speak Japanese, so it took a while to eke out the details.

With a phone line simulator, it’s at least possible to try to have the FCNS try to dial, but that only throws another error. Ultimately it turned out that the FCNS uses NTT’s proprietary DDX-TP (in Japanese) protocol, which isn’t really documented outside of some Japanese sources. This is where the NES Dev site and its forum thread full of FCNS enthusiasts proved essential, as they had already done all the reverse-engineering.

NES Dev user [Ben Boldt], for example, made a DIY version of the FCNS access (tsuushin) card that lets you configure its details. For development, the PLCC-based CPLD was a bit of an annoyance, so the FCNS got somewhat modified along the way for more direct access.

After five months of work, he was finally able to connect the Famicom via the FCNS and a telephone line simulator for some Super Mario Club action. This connects to the SMC Server simulator on the PC, with the detailed manual that comes with the access card helping a lot.

After all this, the Super Mario Brothers game was graced with a game patch that allows for network-based SMB two-player action. This adds a ‘dial’ and ‘answer’ option so that the two Famicoms can connect and commence the two-player session. Although one can question the latency this would entail without a direct POTS connection as here, it is definitely a nifty demonstration of what ultimately would become the multiplayer gaming on Nintendo consoles today.

You can still do Famicom programming. There were even clones.

We’re no strangers to unusual hardware failures around these parts, but even so, a swarm of jellyfish clogging up the works is a new one to us. That’s exactly what happened to the cooling system at the Gravelines nuclear power plant in France earlier this week, resulting in three reactors having to be shut down. This isn’t even an isolated incident, as POLITICO points out that the same thing actually happened last year around this same time.

So why are jellyfish staging an annual protest against nuclear power? A warming of the North Sea has extended breeding seasons and produced larger populations of the plankton that the jellyfish feed on. This is great for the gelatinous sea creatures, but not exactly ideal if you’re trying to pump the water they live in through a complex cooling system. The French installed filter screens and monitoring systems after this happened in 2025, but clearly they’re going to need to keep working on the problem.

From a new problem to a very old one, a BBC investigation has revealed that the UK’s National Health Service (NHS) Blood and Transplant department was inadvertently leaking private patient data by sending it in the clear over the pager network. Sniffing pager messages was fairly trivial decades ago, and is even easier these days thanks to the proliferation of cheap software-defined radios and open source decoding software. Given the fragility of the underlying communication network they use, the NHS announced they were going to stop using pagers by 2021, but clearly not everyone got the memo.

As an aside, we were amused to see that the BBC had to devote a section of the article to explaining what a pager is and why they became popular in the medical field. Of course, it makes perfect sense. Many — perhaps even most — of the people reading the article would never have seen one of the devices in the real world, let alone actually used one. Just a sign of the times, and a great reminder of how old some of us are getting.

Speaking of getting old technology, we came across this web-based emulator for the Flight Data Subsystem used by the Voyager spacecraft. The website lets you write your own assembly code or load up some example programs and watch it execute at a blistering 806.4 kHz. The site also features a real-time display of how far Voyager 1 is from Earth, the current communications delay, and a trove of original Jet Propulsion Laboratory documentation, so even if you’re not interested in writing assembly code for a 1970s computer, it’s worth checking out.

On the subject of running old code in the modern web, you can now play DONKEY.BAS in the browser. The game, now 45 years old, was written by Bill Gates and Neil Konzen to demonstrate the graphics and sound capabilities of BASIC on DOS. For the uninitiated, despite what you might think from the name, the game actually tasks the player with controlling a race car. The donkeys are standing in the road for some reason, and you need to avoid them by switching lanes. With the way the industry is now, we wouldn’t be surprised to hear somebody is working on a gritty origin story film to expand the lore.

Finally, turning our attention to slightly more recent history, [Marcin Wichary] has written a fascinating retrospective on Apple’s Touch Bar. The thin touch screen was introduced in 2016 as a replacement for the top row of the keyboard on the MacBook Pro, and was the subject of some impressive reverse engineering efforts by hackers that wanted to use the unique high-resolution display in their own projects. Apple quietly abandoned the feature in 2023, and [Marcin] makes the case that the problem was never the hardware itself but rather how the feature was implemented in software.

The article includes numerous examples of the redundant and at times downright bizarre user interface elements that would pop up on the Touch Bar, made all the more perplexing given Apple’s usual panache for such things. Although we’re not necessarily convinced the feature ever made a whole lot of sense, given the examples [Marcin] has collected here, it certainly seems like the poorly implemented software side of the equation wasn’t doing it any favors.

See something interesting that you think would be a good fit for our weekly Links column? Drop us a line; we’d love to hear about it.

It used to be a rite of passage to build some sort of AM radio receiver. Many people started with a crystal radio, of course, but you’d graduate to maybe a TRF or superhet design. FM radio projects were not as common, because demodulating an FM signal was harder, as was making things work in the 100 MHz range. These days, though, you can get everything on a chip like the TEA5767, and [turtushig22-blip] has an open design that uses that device on a breakout board, a display, a knob, and an external amplifier. An ESP-32 pulls it together. You can see two videos about the project below.

Unlike older FM radio designs, the TEA5767 doesn’t require any adjustments. RF goes in, and stereo audio goes out. You can control the device through I2C or a 3-wire serial interface.

Software-wise, you send a five-byte control word and the chip sends back five status bytes. You don’t set the frequency directly, but provide a PLL divisor. For example, with a 32 kHz reference crystal, setting 100.1 MHz would be: 4*(100.1 MHz + 0.225 MHz)/0.032768 MHz = (about) 12247.

The radio uses a 225 kHz IF and can autonomously seek stations. You can select whether the search is up or down, and the minimum acceptable signal strength. One unusual feature: the TEA5767 can select the positive or negative mixer output, which might be useful for image rejection in some cases.

The output is purely analog, and there’s no RDS/RBDS decoder. So don’t expect station information on the OLED display. Still, a nice, easy FM radio build. Naturally, not the first TEA5767 build that we’ve seen. Or even the second.

If there’s one defining factor about 3D printing you have to account for when you’re making a design, it’s probably layer adhesion. Sure, there are a lot of factors to consider, but having the z-axis of your part dramatically weaker than x- and y- is a pretty big deal in a whole lot of applications. [I Changed a thing] changed a thing to fix that — namely, he changed his 3D printer by strapping a couple of lasers to it. That’s the kind of hack we like to see!

What the lasers are doing is a very simple idea: they’re pre-melting the last-laid-down-layer just under the nozzle so that molten plastic is meeting molten plastic to create a much stronger joint than you get when you extrude onto an already-cold layer. The second layer keeps the hotspot warmer longer, which also helps the bond. The resulting parts are not purely isotropic, but he’s getting breaking strain along the z-axis of ABS that’s up to 94% of what he’s measuring in the x direction, while PLA still rates at 77.9%. That’s compared to 60% and 41%, for un-lasered samples, respectively. If you watch the video, you’ll get all the details for the printing process and can see more test data.

These lasers look like a game-changer, but their mass might slow down the fast coreXY printers that are so popular these days. If you don’t want to slow down, remember that changing your layer patterns can boost a print’s strength on its own.

Thanks to [Josh Pensel] for the tip!

Sometimes claimed to give you wings, energy drinks can, at the very least, be used to make rockets fly. This is what [Nate Scovill] did in a recent video, where cans of the sugary stuff are processed to give a rocket its proverbial wings.

The basic concept is so-called rocket candy, which uses the fact that sugar is a pretty decent fuel type that — when combined with an oxidizer like potassium nitrate — can be turned into solid rocket fuel. Naturally it’d be easiest to start off with a pure source of sucrose or sorbitol for the sugar, but what if you only have access to cans of sugary soda?

Removing the moisture from the energy drink was the obvious first step, as water and rocket fuel aren’t a great mix. Adding and mixing potassium nitrate to the resulting thick syrup created the fuel-oxidizer mixture, also known as rocket fuel. This did take a detour involving removing the carbonation using a vacuum chamber, as CO₂ and fire do not really like each other either.

We previously covered making your own rocket candy, though it’s far from the only rocket fuel that can be made at home using products bought at the local supermarket. Obviously, doing so comes with a whole heap of risks, not least of which is the notion that the difference between a rocket and a bomb is a pretty thin and fuzzy line that you do not want to accidentally cross.

Steam power is a staple of the steampunk aesthetic, thermodynamics, and a checkpoint for the budding mechanical engineer studying heat cycles. But because food is largely made of water, steam is also common in the culinary arts. So it’s no surprise that when thermodynamics is applied to cooking, exciting things can happen. 

This particular example of steam-powered culinary happenings is inspired by industrial potato-peeling machines. By adding high-pressure, high-temperature steam to a pressure vessel with potatoes inside, heat can transfer more easily to the inside of the potatoes. Because the pressure is so high, however, the water in the skin won’t boil. This is fundamentally the same concept as a pressure cooker. However, what’s different is that instead of a pressure cooker’s slow release, these industrial peeling machines rely on explosive decompression, flash boiling the water underneath the potato’s skin. This rapidly expanding steam rips away the skin in a nice clean sheet.

But, to [Stuff Made Here’s] disappointment, there were no videos of the process on the internet. But, fortunately for us, being an engineer of complicated machines means that there is one now that you can watch below.

The machine itself is, on paper at least, fairly simple. It consists of a boiler, connected to a fruit chamber by a valve, and another valve to vent the steam out of the fruit chamber. However, engineering a pressure vessel that can safely withstand over 1,000 kPa of steam with a window for filming when you can’t weld very well is another matter entirely. The boiler is two stainless steel plates with a cylinder in the middle, with face seals used to keep the chamber steam-tight. A custom jig was needed to machine the pipe ends flat enough to mate with the seals. It’s held together with threaded rods. However, because the rods and the vessel body have different thermal expansion coefficients, Belleville washers are used as expansion joints in the system.

The fruit chamber is welded together because it experiences lower pressures. This also allows for a less sensitive O-ring seal on the door, reducing the work required to use the door. A glass piece inlaid into the steel door provides a view, held in place by pressure and 3D-printed brackets. A stand holds the fruit centered within the window for our viewing pleasure!

The results speak for themselves, though operation is complicated and dangerous, and it can only peel one fruit at a time; the skin of nearly every example placed inside is perfectly removed. Experiments include apples, potatoes, grapes, lemons, strawberries, blackberries, and (pictured above) popcorn on the cob. It’s quite a fun demonstration of the thermodynamic principles at play!

Thanks [DjBiohazard] for the tip!

It’s a sci-fi trope that you can ‘scan for life signs’ and detect if there are humans — or suspiciously human-shaped aliens — present, but in real life it’s harder than that. [The Masked Bear]’s wifisense-pi project isn’t really scanning for signs of life, either, unless you happen to consider breathing a sign of life. Even then, it’s not detecting breathing per se, but the subtle motion that goes with it: it’s a very sensitive motion detector that relies on the fact that we fleshy bags of goo disturb WiFi signals with our presence, and motion alters those disturbances.

The device uses an ESP32-S3 to measure the radio channel 100 times per second, while a Raspberry Pi 4 provides the signal processing muscle. It can detect the slightest motions, and even determine the presence of a perfectly still human by their breathing, though you can hide your presence for as long as you can hold your breath. A single sensor, no matter how sensitive, cannot give position information, and while multiple humans will distort WiFi more than a single one, [The Masked Bear] reports you cannot reliably extract that signal. So this project answers the question: “are there humans in this room?” Or, even more likely, “are there any large breathing animals in this room?” We can’t imagine a 50 kg Mastiff looking any different to this sensor than an equivalent mass of quivering human flesh.

Before you dismiss this as just another motion sensor, keep in mind that it is sniffing the signals already present on the 2.4 GHz band, and, like the WiFi signals themselves, it can work through walls. So we think it’s pretty nifty. Of course, there are many other ways to detect humans, from machine-learning cameras to millimeter-wave sensors to a simple PIR. This isn’t the first project we’ve seen that uses WiFi like this. It isn’t even the first with an ESP32, but it’s an interesting implementation worth checking out.