Ferrites Versus Ethernet In The Ham Shack

For as useful as computers are in the modern ham shack, they also tend to be a strong source of unwanted radio frequency interference. Common wisdom says applying a few ferrite beads to things like Ethernet cables will help, but does that really work?

It surely appears to, for the most part at least, according to experiments done by [Ham Radio DX]. With a particular interest in lowering the noise floor for operations in the 2-meter band, his test setup consisted of a NanoVNA and a simple chunk of wire standing in for the twisted-pair conductors inside an Ethernet cable. The NanoVNA was set to sweep across the entire HF band and up into the VHF; various styles of ferrite were then added to the conductor and the frequency response observed. Simply clamping a single ferrite on the wire helped a little, with marginal improvement seen by adding one or two more ferrites. A much more dramatic improvement was seen by looping the conductor back through the ferrite for an additional turn, with diminishing returns at higher frequencies as more turns were added. The best performance seemed to come from two ferrites with two turns each, which gave 17 dB of suppression across the tested bandwidth.

The question then becomes: How do the ferrites affect Ethernet performance? [Ham Radio DX] tested that too, and it looks like good news there. Using a 30-meter-long Cat 5 cable and testing file transfer speed with iPerf, he found no measurable effect on throughput no matter what ferrites he added to the cable. In fact, some ferrites actually seemed to boost the file transfer speed slightly.

Ferrite beads for RFI suppression are nothing new, of course, but it’s nice to see a real-world test that tells you both how and where to apply them. The fact that you won’t be borking your connection is nice to know, too. Then again, maybe it’s not your Ethernet that’s causing the problem, in which case maybe you’ll need a little help from a thunderstorm to track down the issue. Continue reading “Ferrites Versus Ethernet In The Ham Shack”

Latest PiEEG Shield Now Offers 16 Channels

We’ve previously covered the PiEEG, an affordable brain-computer interface (BCI) shield designed to connect to the Raspberry Pi. The open source project developed by [Ildar Rakhmatulin] is intended to allow students and hobbyists to experiment with detecting electroencephalography (EEG), electromyography (EMG), and electrocardiography (ECG) biosignals — unlocking a wide array of applications ranging from assistive tech to gaming.

Now, the PiEEG hardware has been upgraded to detect sixteen channels via either wet or dry electrodes. The new board, referred to as the PiEEG-16, offers up the same ease of use and features as its predecessor, including the ability to read out signals from the device using Python scripts. Compared to the eight channels supported by the previous generation of hardware, the PiEEG-16 promises to provide the fine-grain data required for more complex operations.

Since we last checked in with the PiEEG back in 2023, [Ildar] says the project has attracted plenty of attention. To help document how the community is using the capability offered by these BCIs, he’s added a page on the project’s site to show off what folks are building with the technology.

Inevitably, some express concern when talking about non-professionals working with brain interfacing hardware. But the project’s documentation is quick to point out that efforts have been taken to make the endeavour as risk-free as possible. The most important thing to remember is that the Raspberry Pi and PiEEG are intended to be powered by batteries so as to remain completely isolated. Similarly, there’s no need to connect the devices to a mains-powered computer, as everything happens on the Pi itself.

Even still, it’s made clear that the PiEEG-16 is not a medical device, and has received no formal certifications. If you want to experiment with this technology, you do so at your own risk. Just something to keep in mind…no pun intended.

Continue reading “Latest PiEEG Shield Now Offers 16 Channels”

New DuckyPad Pro Is Bigger And Smarter Than Original

In a world that has no shortage of macropads, the duckyPad still managed to set itself apart. The open source mechanical pad offered an incredible array of customization options, and thanks to its onboard OLED display, you never had to wonder which key did what. But there’s always room for improvement.

Announced earlier today, the duckyPad Pro is the culmination of everything creator [dekuNukem] learned from developing, marketing, and supporting the original duckyPad. Much hasn’t changed — it looks largely the same, offers the same RGB-backlit mechanical switches, and the trademark OLED is still there, although it’s gotten a little larger. The obvious changes are the addition of five more keys, and a pair of rotary encoders.

Continue reading “New DuckyPad Pro Is Bigger And Smarter Than Original”

2024 Hackaday Superconference Speakers, Round One

Supercon is the Ultimate Hardware Conference and you need to be there! We’ve got a stellar slate of speakers this year — way too many to feature in one post. So here’s your first taste, and a reminder that Supercon will sell out so get your tickets now before it’s too late.

In addition to the full-length talks, we’ve got a series of Lightning Talks, so if you want to share seven minutes’ of insight with everyone there, please register your Lightning Talk idea now.

But Supercon has a lot more than just talks! The badge heavily features Supercon Add-Ons, and we want to see the awesome SAOs you are working on. There will be prizes, and we’ll manufacture four of our favorite designs in small batches for the winners, and make a full run for Hackaday Europe in 2025. Want to know more about SAOs? They’re the ideal starter PCB project.

Continue reading “2024 Hackaday Superconference Speakers, Round One”

PC Floppy Copy Protection: Electronic Arts Interlock

Continuing the series on floppy copy protection, [GloriousCow] examines Electronic Arts’ Interlock system. This was used from 1984 to 1987 for at least fourteen titles released on both 5.25″ and 3.5″ floppies. Although not officially advertised, in the duplication mark sector the string ELECTRONIC ARTS IBM INTERLOCK. appears, hence the name. Compared to other copy protection systems like Softguard Superlok this Interlock protection poses a number of somewhat extreme measures to enforce the copy protection.

The disk surface of Side #0 of the 1984 mystery-adventure title, Murder on the Zinderneuf (Credit: GloriousCow)
The disk surface of Side #0 of the 1984 mystery-adventure title, Murder on the Zinderneuf (Credit: GloriousCow)

Other than the typical issues that come with copying so-called ‘booter’ floppies that do not use DOS but boot directly into the game, the protection track with Interlock is rather easy to spot, as seen on the right. It’s the track that lights up like a Christmas tree with meta data, consisting out of non-consecutive sector IDs. Of note is the use of ‘deleted’ sector data marks (DDAM), which is a rarity in normal usage. Along with the other peculiarities of this track it requires an exact query-response from the disk to be accepted as genuine, including timings. This meant that trying to boot a straight dump of the magnetic surface and trying to run it in an emulated system failed to work.

Reverse-engineering Interlock starts with the stage 0 bootloader from the first sector, which actually patches the End-of-Track (EOT) table parameter to make the ridiculous number of sectors on the special track work. The bootloader then loads a logo, which is the last thing you’ll see if your copy is imperfect.

Decrypting the second stage bootloader required a bit of disassembly and reverse-engineering, which uncovered some measures against crackers. While the actual process of reverse-engineering and the uncovered details of Interlock are far too complex to summarize here, after many hours and the final victory over the handling of an intentional bad CRC the target game (Murder on the Zinderneuf from 1984) finally loaded in the emulator.

After confirming the process with a few other titles, it seems that Interlock is mostly broken, with the DOS-based title ArcticFox (1987) the last hurdle to clear. We just hope that [GloriousCow] is safe at this point from EA’s tame lawyers.

Interested in more copy protection deep dives? Check out the work [GloriousCow] has already done on investigating Softguard’s Superlok and Formaster’s Copy-Lock.

Apple May Break Into The Hearing Aid Industry

When the entry of a tech giant such as Apple into a market represents its liberation from exploitation, that market must be really broken, yet the reported FDA approval of the hearing aid feature in the latest AirPod earbuds seems to represent just that. The digital hearing aid business is notorious for its sharp sales practices and eye-watering prices, so for all Apple’s own notoriety the news might actually represent a leap forward for consumers in that sector. We have to ask though, if Apple of all people are now the Good Guys, where has the world of electronics gone so badly wrong?

Your grandparents decades ago would have had a simple analogue hearing aid if they had one, usually a small transistor circuit and perhaps with some kind of analogue filtering.  Digital aids with DSP algorithms to pick out speech arrived some time in the 1990s, and from there evolved a market in which their high prices increasingly didn’t match the cost of the technology or software involved. At least in the UK, they were sold aggressively to older people as less cumbersome or better than the National Health Service aids, and if you had an older person in the family it was routine to see pages and pages of targeted junk mail offering dubious financial schemes to pay for them.

The question then, given that a modern hearing aid has a relatively cheap microcontroller and DSP at its heart, why has the open source community not risen to the challenge? The answer is that they have, though the Tympan seems an over-expensive trinket for what it is and the LoCHAid and Open Speech Platform seem to have sunk without trace. Can we do better?

Header: Gregory Varnum, CC BY-SA 4.0 .

The Rise Of Self-Cleaning, Cat-Killing Litter Boxes

Machines that automate the various tedious tasks that come with being a servant in a cat’s household — like feeding and cleaning Mr. Fluffles’ litter box — are generally a godsend, as they ensure a happy cat and a happy human. That is, unless said litter box-cleaning robot kills said cat. That’s the gruesome topic that [Philip Bloom], also known as the bloke of the One Man Five Cats channel on YouTube, decided to investigate after coming across a report about a certain Amazon-bought unit.

The theory of a self-cleaning litter box: a happy Mr. Fluffles.
The theory of a self-cleaning litter box: a happy Mr. Fluffles.

Although he was unable to get the (generic & often rebranded) unit off Amazon UK, he did get it via AliExpress for £165 + £80 shipping. Although this version lacks the cute ears of other variants, it’s still effectively the same unit, with the same moving components and mechanism. An initial test with a cat plushie gave the result that can be observed in the above image, where the inner part with the opening will move upwards, regardless of whether a cat is currently poking through said opening. Once the victim is stuck, there is no obvious way to free the trapped critter, which has already led to the death of a number of cats.

The other self-cleaning litter boxes which [Philip] owns have a number of safety features, including a weight sensor, an infrared sensor above the opening to detect nearby critters, a top that will pop off rather than trap a critter, as well as a pinch sensor. During a test with his own hand, [Philip] managed to get injured, and following a banana test, he had a nice banana smoothie.

What takes the cake here is that after [Philip] connected the mobile app for the litter box, he found that there was a firmware update that seems to actually change the machine to use the pinch and infrared sensors that do exist in the litter box, but which clearly were not used properly or at all with the shipped firmware. This means that anyone who buys any of these self-cleaning litter boxes and does not update the firmware runs the significant risk of losing their pet(s) in a gruesome incident. In the video a number of such tragic deaths are covered, which can be rather distressing for any cat lover.

Of note here is that even with the improved firmware, any issue with the sensors will still inevitably lead to the tragic death of Mr. Fluffles. If you do want to obtain a self-cleaning litter box, make sure to for example get one of [Philip]’s recommendations which come with a paw stamp of approval from his own precious fluff balls, rather than a random unit off Amazon or AliExpress.

Continue reading “The Rise Of Self-Cleaning, Cat-Killing Litter Boxes”