When we use an electronic component, we have some idea of what goes on inside it. We know that inside a transistor there’s a little piece of semiconductor with a junction made from differently doped regions etched into it, and in a capacitor, there will be metalized plates on the surface of some kind of dielectric. Reverse engineering has given us extensive die photography of integrated circuits, but there remain a few component mysteries to be uncovered. One is laid bare by [WizardTim], as he cross-sections a 20KV high-voltage diode.
A conventional low-voltage silicon diode has a forward voltage drop of about 0.7V and a relatively low maximum reverse voltage, for example with the 1N4001 rectifier it’s 50V. For the higher-spec 1N4007, the reverse voltage rating is 700V. This diode has a 25KV reverse voltage, and a clue to its construction comes in its quoted 45V forward voltage. Sure enough, when mounted in resin and carefully sanded and polished flat it reveals its interior as a stack of diodes in series to increase the reverse voltage at the expense of forward voltage.
Revealing the inner workings of an unusual component is fascinating, and the lapping technique used is definitely worth a look. It’s something we’ve seen before, for example in reducing CPU thickness for increased performance.
Over the last couple few decades there has been a great shift in electric lighting, first towards more compact and efficient fluorescent lights, and then towards LED bulbs. The old incandescent bulbs, while giving a pleasant light, were not by any means efficient. Digging into the history books the incandescent bulb as we know it was not the only game in town; while suspending a filament in a vacuum stopped it from being oxidized there was another type of light that used a ceramic element at atmospheric pressure. The Nernst lamp required its filament to be heated before it would conduct electricity, and [Drop Table Adventures] has made one using the blade from a ceramic potato peeler.
The right ceramic is not the problem given the ease of finding ceramic kitchen utensils, but two problems make a practical light difficult. The copper connections themselves become too hot and oxidize, and preheating the ceramic with a blowtorch is difficult while also keeping an even heat. Finally, they do manage a self-sustaining lamp, albeit not the brightest one.
With mass vaccination programmes and careful application of public health measures it almost feels for some of us as though the pandemic is under control. Any thoughts of it being over are illusory though, and if further reminders were needed we have the news that once more this year’s Chaos Communication Congress has been cancelled due to the safety of its attendees and the extra precautions that its organizers would have to undertake.
This event in Leipzig between Christmas and New Year is probably the largest of the European gatherings in our community, and its loss will be a great disappointment. Last year’s cancelled event was replaced by a remote one, we’ll see whether they repeat that feat in 2021. If so, we’ll be there, virtually.
We can only sympathise with our German friends, as while it must be extremely annoying it’s to their credit that they are taking the pandemic seriously. We’re sure that they will be back with the same event in 2022 as the world slowly inches towards normality, and Hackaday will be there to bring you the best of the event.
Somehow we didn’t do a big overview post of the 36C3 in 2019, so if you want to bask in the glory of a Congress, you have to travel back in time all the way to 35C3 in 2018, long before the arrival of COVID-19.
Those of us who have followed the Raspberry Pi over the years will be familiar with the various revisions of the little board, with their consequent new processors. What may be less obvious is that within the lifetime of any chip there will often be minor version changes, usually to fix bugs or to fine-tune production processes. They’re the same chip, but sometimes with a few extra capabilities. [Jeff Geerling] didn’t miss this when the Raspberry Pi 400 had a BCM2711 with a newer version number than that on the Pi 4, and now he’s notices the same chip on Pi 4 boards.
Why might they run two different revisions of the chip in parallel? It seems that the update changes the amount of memory addressable by the eMMC and the PCIe bus, the former could only see the first 1GB and the latter the first 3Gb. For the lower-spec Pi 4 boards this doesn’t present a problem, but for those with 8 gigabytes of memory it could clearly be an issue. Thus the Pi 400 and the top spec Pi 4 now have a newer BCM2711 version. This will almost certainly pass unnoticed for the average Raspberry Pi OS user, but the extra memory addressing space should be of interest for hardware experimenters wishing to expose that PCIe bus and talk to peripherals such as a GPU. That said, though he suggests the Compute Module 4 has the newer revision, his own experiments were unsuccessful.
[Editor’s Note: our own overclocking experiments show the C-version SOCs to run cooler/faster than their B counterparts, so it’s nice to have the better chips in the “normal” Pi form factor and not just the Pi 400 and compute modules.]
Followers of alternative energy technology will remember how earlier in the year a battery container at Tesla’s Megapack Australian battery grid storage plant caught fire. Lithium ion batteries are not the easiest to extinguish once aflame, but fortunately the fire was contained to only two of the many battery containers on the site.
The regulator Energy Safe Victoria have completed their investigation into the incident, and concluded that it was caused by a coolant leak in a container which caused an electrical component failure that led to the fire. It seems that the container was in a service mode at the time so its protection systems weren’t active, and that also its alarm system was not being monitored. They have required that cooling systems should henceforth be pressure tested and inspected for leaks, and that alarm procedures should be changed for the site.
When a new technology such as large-scale battery storage is brought on-line, it is inevitable that their teething troubles will include catastrophic failures such as this one. The key comes in how those involved handle them, and for that we must give Tesla and the site’s operators credit for their co-operation with the regulators. The site’s modular design and the work of the firefighters in cooling the surrounding packs ensured that a far worse outcome was averted. Given these new procedures, it’s hoped that future installations will be safer still.
In our community it’s certain that there will be many people with very strong views about patents. It’s fair to say that the patents system is at times not fit for purpose, with such phenomena as patent trolls, submarine patents, and patent war chests doing nothing but leading it into disrepute. So it’s interesting to read the words of 3D printer hotend manufacturer E3D, as they talk about why they feel the need to patent some of their inventions, and how they intend to proceed with them.
The result is a no-nonsense explanation of why their work being reproduced by overseas competitors has brought them to this point, and in short: they’re patenting very specific inventions rather than broad catch-alls, they are making what they call a legally binding promise not to enforce the patents against non-commercial or academic experimenters, and they will continue to open-source as much as they can.
Will it work for them, or is it the start of a slippery slope? We can see why the E3D folks have taken this step, and we hope that they will continue to act in a responsible manner. If not, as those who have followed the maker-oriented 3D printing business for a long time will know: treading the line between open-source and closed-source can be fraught with danger.
If you are a follower of retrocomputing, perhaps you caught the interactive Black Mirror episode Bandersnatch when it came out on Netflix. Its portrayal of a young British bedroom coder finding his way into the home computer games industry of the early 1980s was of course fictional and dramatised, but for those interested in a real-life parallel without the protagonist succumbing to an obsession with supernatural book there’s a recent epic Twitter thread charting an industry veteran’s path into the business.
An acceptance letter like this from Artic Software would have been the wildest dream of any early-80s bedroom coder.
[Shahid Kamal Ahmad] now has an impressive portfolio spanning his his nearly four decades at the forefront of gaming, but his story starts in 1982 as a diabetic British Pakistani teenager from a not-privileged background in London writing in BASIC on his Atari 400. His BASIC games are good, but not good enough to gain acceptance from a publisher, so he sells his prized BMX bicycle to buy books on Atari 6502 assembler, a coffee percolator, and for curiosity’s sake, [Rodnay Zaks’] Programming the Z80. An obsessive three-month learning of 6502 programming and the Atari’s architecture ensues, and his game Storm in a Teacup sells to Artic Software. He’s a professional game developer.
We follow him through a couple more projects until he arrives at Software Projects in Liverpool to try to sell his game Faces of Haarne, which he secures publishing for but also lands the opportunity of a lifetime. Jet Set Willy is the smash hit of the year on the ZX Spectrum, and they urgently need a Commodore 64 port. Can he do it in four weeks, with a bonus if he manages three? The subsequent descent into high-pressure assembly coding and learning the quirks between two completely different 8-bit architectures is an epic in itself, but he manages it in just a shade over the three weeks and they pay him the bonus anyway. His career in the computer game industry is cemented.
Through this tale the reminders of 1980s Britain are everywhere, far from bring a retro paradise it was a place hollowed out by industrial decline, with very little for those at the bottom of society to be optimistic about. His descriptions of casual racism are hard-hitting, but the group of computer-addicted friends at school is probably something that all teenagers of the era whose interests lay in that direction can relate to. The real hero of the story is probably his mother, who somehow found the resources for that Atari 400 and who provided him with much-needed support and encouragement.
This thread captures a unique and never-to-be repeated era in which a teenager could master an emerging technology and make a living in it without an expensive education. Like Bil Herd’s description of his career at Commodore in the same period, it’s well worth a read.
