Mysterious Files PH

We are all in search of the fastest in a wireless router, to give ourselves the best connectivity to the world. But what about the slowest? Gigabit Ethernet may not be for everyone, as Matt Deeds demonstrates with bit-banged 10baseT Ethernet on a Raspberry Pi Pico 2W.

The project is written in Rust, and is in part a port of an earlier project. It makes use of Ethernet magnetics, but the rest of the works is all done in software. He says it’s full-speed on transmit and reduced speed on receive, but we’re guessing if you’re using 10baseT in 2026 then speed isn’t your number one concern anyway. It provides a WiFi router as well as a wired connection, making it possibly the cheapest Ethernet to wireless solution possible.

We like projects that extract the last ounce of power from a part to make it do something its designers never intended. In this case we’ve seen a few other bit-banged Ethernet projects before, even another on the Pi Pico.

Some security hacks require someone to have physical access to your computer. In many cases, that’s easy to mitigate. Other attack vectors can put you at risk from anywhere via the network. That’s what firewalls are for. But there is an in-between risk where an attacker just has to be “around” your computer. [Rasmus Moorats] found out that a Creative Sound Blaster sound bar could open up just such an attack.

[Rasmus] was poking around the firmware just to write custom software to control it. The possibility of an attack was just an accidental find.

The soundbar connects to USB, but it also has Bluetooth, which, for some reason, is always on. There’s an app that can communicate with the speaker using BLE, and Creative has a special protocol to control it. The same protocol works on USB or Bluetooth, but with an important difference.

On USB, you have to authenticate to send commands. However, you can easily decompile the provided apps and learn the authentication key. But on BLE, it doesn’t require authentication at all for some reason. You can simply send commands via BLE, and the speaker obeys. No pairing. No physical access. Just be close enough for a Bluetooth connection.

The worst of the commands lets you reflash the device firmware. So, if you were a bad actor, you could flash firmware to act as a USB keyboard and then inject lots of bad commands into the host system.

BLE seems to be a common vector in consumer electronics. Maybe now you have to air-gap your speakers, too.

Adding magnets to a 3D print can be very useful in a design, but there are some things that can trip you up if you’re not away of them. In a recent video by [Lost in Tech] some of the essentials are covered, including why you shouldn’t get magnets near most extruder nozzles or the printing bed.

The easiest method is of course to add magnets in after printing, using friction fit with or without ribs, or with a dab of glue. Here making sure that the magnet stays in place is the trick, as you do not want the magnet to get lost or end up in the tummy of a curious pet or toddler.

Things get spicy when you’re talking about adding magnets during the printing process, as some extruders are made of a ferromagnetic material and thus a magnet will happily stick to said nozzle if it’s not pure brass or similar. As seen in the video even some purported ‘brass’ nozzles aren’t pure enough to not be significantly ferromagnetic.

Another issue is that of heat, which is something that magnets generally do not like much. Using magnets like you’d use heat inserts for bolts is a recipe for disaster, as the heat from a soldering iron will demagnetize the magnet, which for the typical magnet is less than 200°C. At least this should mean that the magnet stuck to your extruder nozzle will eventually fall off by itself after it demagnetizes.

With the bed of the typical FDM printer these days you’re talking about magnetically attached plates, with the underlying heated bed using a Halbach array configuration as is typical of flat magnets, yet with the gotcha that these aren’t typically real Halbach arrays, but knock-offs with simply alternating north-south pole magnets. As it turns out, these types of magnetic arrays can be disturbed by another magnet, such as a powerful neodymium magnet near said printing bed, flipping polarity in a way that cannot be easily undone.

You can still install magnets during printing, but it’s recommended to use something like side-insertion, where the extruder nozzle cannot pull out a magnet. Regardless of your approach, it’s good to know of the risks with ferromagnetic nozzles, the magnetic bed and treating magnets like they’re just heat inserts. While you can get higher-temperature magnets, many of the same issues still remain here.

The most recent Hackaday event badge has been the Communicator, a handheld wireless terminal with a rather nice QWERTY keyboard. It’s good enough as delivered, but [makeTVee] has gone one better and made his Communicator keyboard into a fully RGB light-up experience.

The feat is achieved with the help of a new front panel holding some very thin side-emitting addressable LEDs. The keys are custom-printed, and there’s a TPU mat to hold them all together. The LEDs are driven from one of the device’s GPIOs.

We saw this badge in real life at the recent Hackaday Europe conference in Lecco, Italy. It really is as good as it looks in the video below, the care and attention which has gone into the build is extremely impressive.The original badge used a silicone cast set of keys, and we’d say if you are making a device with a keyboard then these might make a very good option.

If you’re not familiar with the Communicator, it’s worth having a look at the launch announcement.

The GRiD Compass is a legendary portable computer — a taste of an early-80s future with bubble memory, tough enough for NASA to take them into space, and one of the machines which defined the beginnings of the form factor we know today as a laptop. They’re not easy to come by, but [Scott M. Baker] got his hands on one. As well as nursing it back to health, he’s made an unusual peripheral, a GPIB speech synthesizer.

The GRiD arrived in one piece despite sketchy packaging, and after a little confusion over its line voltage it ran as well as the day it was made. It was designed to use GPIB as its interface for large peripherals such as printers or disk drives, so it was that interface picked for the speech synthesizer. It emulates a GPIB printer, and bytes are sent to the synthesizer chip by printing to LPT1, making driving it an easy process.

The synth itself is a clever design that allows the use of all the various speech chips of the day. It achieves this using a GPIB carrier board holding the interfacing, and a set of plug-in modules, one for each different chip. It’s certainly an unusual peripheral.

You can see more details in the video below the break, meanwhile if you can’t get the real thing there’s a cyberdeck tribute you can make.

Restoring a GRiD Compass and Building the World’s First GPIB Speech Synthesizer

First introduced in 1979 by Signetics, the NE5532 was a pretty spiffy dual op-amp for the time with low noise and low distortion. Over the years it has become a standard part that showed up in countless audio products, and has become a so-called jellybean generic component with Texas Instruments (TI) being one of countless manufacturers.

It being such a standard, multi-sourced part makes it thus even more puzzling that TI has now decided to completely overhaul this IC in a way that makes it incompatible with even the original Signetics NE5532. These changes are covered in detail by [Dave] of EEVblog as his mind is pretty much blown at such an incomprehensible change.

The changes entail an entirely different manufacturing process and a big change in specifications, while making no change to the part number. In revision K of the TI datasheet these changes are first seen, with some specifications changed for the better, like a higher unity gain bandwidth by 2 MHz, but a much slower slew rate.

Although the 5532 op-amps are multi-sourced, there are good reasons to just stick with manufacturers like TI, as that means receiving a product change notification (PCN) when anything changes. In the PCN related to this op-amp a change to process node is noted, along with other changes, but no reasoning.

Among the other big changes are a reduction in the supply voltage from 22V to 18V, and a halving of the ESD protection from 2kV to 1kV. Although it might be slightly more efficient on the new process node this way, it clearly comes with a lot of trade-offs that make it an overall worse op-amp, while also being incompatible with the same op-amp from other manufacturers.

In the video [Dave] goes through the datasheets of this jellybean part of other manufacturers, showing that they still have the original 1980s specifications. Only one exception here was the NE5532DR from Shenzhen HuaXuanYang Electronics, whose supply rail voltage is also 18V for some reason, along with a similar internal transistor configuration that reduces the ESD resistance.

In addition to the NE5532 op-amp, it seems that TI also took an ax to the OPA134 op-amp, by removing its offset trim feature and listing the pins as ‘NC’, with a warning to not connect these pins and also worsening other specifications. This makes these similar jellybean parts incompatible, with no change to the part number. Worse is that it continues with the LMH6518, whose changes [Dave] argues might even kill oscilloscopes as they are commonly found in those.

Meanwhile the LM317M also got an overhaul, but here TI opted to give it a new part name, calling it the LM317MQ with at first glance no major degradations in the specifications, but instead some actual improvements. This makes it even more puzzling why TI didn’t give the other ICs a new part number to differentiate them from the jellybean part.

Until there’s some clarification from the side of TI, it might be a good idea to source these jellybean parts from a manufacturer that is not TI, especially when replacing these ICs in older devices.

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.