Paper as a substrate for electronic circuits is not very common, but promising for flexible circuits with low cost and easy recyclability. That said, paper is not an easy material to work with when printing traces, as the cellulose material is both absorbent and irregular, limiting the resolution and accuracy of so-called papertronics. Even when using higher-quality paper with wax-based masks this resulted in poor resolution issues, so [Zahra Rafiee] et al. opted to approach the problem from the other direction, by using hydrophobic parchment paper as the base combined with a laser.
The nice thing about the inks used with papertronics that they aren’t just traces, but can also be functional elements like resistors, which is also demonstrated in the paper. The channels for the inks are created using a 50 Watt CO2 laser, which etches away the silicone coating on the parchment paper. The achieved resolution in the article is around 250 µm for line widths and 300 µm line spacing, which is much better than that for wax-based alternatives.
Some of the cotton candy options by the machine. The Chinese text reads ‘flower type’.
Having a fully automated cotton candy vending machine in your possession is a great thing, but not if you do not have full access to its software. With [Block’s Retro Repairs] getting ghosted by the manufacturer on regaining account access to the machine he bought used for $300, there was little left but to try and break into the system.
We previously covered the journey in getting the vending machine back into a state where it’d actually reliably produce cotton candy again, a process which is quite tedious and temperamental. After a lot of fiddling with sensors and temperature settings this was fixed, but still left the issue that as a vending machine it should allow the owner to set prices and such. Sadly this could only be done remotely via a special account, which access to had been left with the previous owner.
Despite the very custom exterior, the vending machine runs what is effectively an Android system, consisting of an industrial computer board wired into a lot of stepper drivers and other control boards. To the extreme delight of everyone involved, it was possible to access the Ct Terminal application with adb and its product database on the device’s storage. Unfortunately writing back a changed database file didn’t change anything in the UI, so for a few months the project languished.
After nearly bricking the system and ending up factory resetting the control software including temperatures, it actually improved the performance of the machine and produced cotton candy, so that was one win. Ultimately the solution was to modify the original app, but a combination of weak coding skills and the app being in Chinese led him to use free LLM coding chatbots to assist here.
This resulted in a custom settings menu being added with the ability to modify pricing, no need for online access any more and a very nice cotton candy vending machine for the private arcade where presumably friends and family can enjoy cheap or even free cotton candy. Finally having the machine sealed against ant intrusion was also a major improvement.
When the Chernobyl Nuclear Power Plant’s #4 reactor experienced an extreme criticality event on that infamous day in 1986, the resulting steam explosion and lack of any kind of containment building meant that parts of the core were scattered throughout the site. In an extensive update to the original 2023 video, the [Chornobyl Family] covers the mad scramble to design robots to perform on-the-ground measurements, and ultimately remove all this debris for safe disposal.
The TR-1A, an early debris removal robot. (Source: Chornobyl Family, YouTube)
This essentially took the form of a hackathon, involving teams from all over the USSR and allied nations, creating the most diverse range of robots that 1980s Soviet technology and later Western technology could muster.
Many of these robots didn’t perform very well, or at all, mostly due to the bypassing of any kind of testing before deployment. Especially at the beginning of the clean-up the robots were being pushed into the high-radiation zones as soon as they were finished, with not only mechanical issues being a problem, but also with e.g. inaccurate radiation measurements by the RR-1 robot, that overstated measurements by more than a factor of ten. Meanwhile the RR-2 and RR-3 were too top-heavy and after deployment by helicopter simply tipped over. Eventually manual measurements proved to be faster and safer.
Early debris removal robots like the TR-1A were rather simplistic, with successive generations of robots over the next weeks and months improving on it. The use of a combustion engine instead of batteries provided to be a boon, as combustion engines are far less affected by radiation.
The BAER Beloyarets used an airport cart as the basis, with its electronics relying on vacuum tube technology and relays, with an internal combustion engine. This proved to be one of the most reliable designs and it’s been largely preserved on display in the Chornobyl Exclusion Zone, with many others of these robots also being on display around the nuclear plant or in the city of Chornobyl.
Overall an absolutely dizzying number of robotic designs were invented on the spot, adapted from existing designs or repurposed for operation in a high-radiation zone. Eventually bulldozer designs like the STR-1 helped to push radioactive debris off the roofs into containers, massively reducing the radioactive contamination of the area.
The fact that following #4’s RUD the other three RBMK units were able to keep operating safely without risks to its operators, and with the zone now safe for tourists, is a real testament to the success of the worst hackathon imaginable. Many of the lessons learned are relevant today, including during the decommissioning of Fukushima Daiichi’s melted-down cores.
Letting go is hard, especially when it concerns an irreplaceable space probe like the two Voyagers. Fortunately JPL engineers have managed to pull off a ‘big bang’ switch on Voyager 2, involving two heaters and another device that was kept on to keep providing sufficient heat to the spacecraft to allow it to keep functioning. After all, while the vacuum of space isn’t cold, out in deep space you’re radiating away all your precious heat.
Unfortunately the official press release is exceedingly limited in details, but The Register was kind enough to nag a NASA spokesperson about it, and gave us some technical details. The short version is that these heaters don’t just keep the electronics within a happy operating range, they also keep the fuel lines warm and capable of providing fuel for attitude adjustments.
With this switch, apparently enough of the rapidly diminishing power from the RTG has been freed up that the Voyager 2 has just gained a whole extra year on its extended mission. The JPL team hopes to perform the same switch on the Voyager 1 spacecraft soon, giving it a similar boost to its expected lifespan, before both of them go quiet in the depths of space.
Back in the late 90s, Apple was definitely a pretty fruity company, with its aggressively translucent shades of colored plastic that often got described in terms of such fruit variants. Although the iMac steals a lot of the glory here, the Power Mac series and associated hardware deserves that spot in the limelight as well. Recently [Dan Wood] put together a full Power Mac G3-based setup, including the appropriate LCD monitor and other peripherals as someone with some serious disposable income back in 1999 might have owned.
Why Macs are better than PCs. (Credit: Dan Wood, YouTube)
Part of Steve Jobs’ return to Apple, the Power Macintosh G3 debuted first in basically recycled beige enclosures from previous Macintosh systems before its second generation introduced the Blue and White version, as it was officially called. This dazzling style was carried through in the peripherals, with pin stripes, translucent plastic and a distinct absence of sharp corners or edges.
As for what you get in these colorful Power Mac G3s, a 300 to 450 MHz CPU, an official memory limit of 192 MB and perhaps the most user-friendly way to access the logic board to upgrade and install components with the folding lid. Something which had PC users with sharp edged cases and plentiful blood sacrifices to the PC gods somewhat steaming in jealousy.
For the time these Power Mac G3s didn’t just look fetching, they also were quite powerful. Something which came at a pretty hefty price tag, of course. The 400 MHz model that [Dan] got his paws on would have cost around $2,000 back in 1999, or closer to $4,000 clams today. The active-matrix TFT LCD screen would have been cutting edge as well, with a similar cutting edge price tag.
Released before OS X this system runs Mac OS 8.6, though it can run OS X 10.4 (Tiger) which unlocks more software options and of course the transition to a proper multi-tasking OS. This particular system was apparently used for graphics design until 2010 based on the files on the HDD. As demonstrated in the video, the system is still quite usable, even in 2026, thanks to all the software available online.
It’s rather awkward when you buy a piece of hardware like a sketchy router to make a video about its hidden admin password backdoor – known as CVE-2026-11405 – only to discover that you bought the wrong Tenda router, namely the AC10V6 model. After making this mistake, [Low Level] did the only reasonable thing one ought to do in this case, and try to find an exploit in this ‘wrong’ router as well.
The obvious start here is to do the same as with the other exploit, in that you download a firmware image from the manufacturer’s website, then pluck it apart using binwalkto do an initial check for juicy files. After that tools like Ghidra can be used to do a more in-depth analysis of any binary files, with a special focus on things like user-facing elements like login screen, as input validation will likely forever remain the number one type of exploited CVE.
One major change that Tenda made here was to encrypt the firmware image, which seemed suspicious. With that easy path blocked, the research of others on different Tenda routers was looked at, including the AC20 with the fascinating Telnet exploit in the form of CVE-2025-9090 where merely poking a file on the device turned on the Telnet service. This left the minor issue of finding a password to log into said Telnet session.
Die of the Amazon Fire Stick HD (2026) PMIC IC. (Credit: electronupdate, YouTube)
After the release of Google’s Chromecast so-called ‘streaming sticks’ have remained a popular form factor, even though such technology is these days part of ‘smart’ TVs. Being curious as to what kind of hardware they put into these sticks or dongles these days, [electronupdate] decided to do his typical full teardown of a 2026 model Fire Stick HD from Amazon, including the typical nekkid die shots.
Although most of the bits inside are fairly typical, being just your typical Mediatek-sourced solution, the ceramic patch antennas for Bluetooth and Wi-Fi are a rather interesting detail, as are the purported limitations that make this the ‘HD’ version of the Fire Stick, unlike its 4K brethren.
The used Mediatek MT8698D SoC isn’t so different from the SoC in those 4K versions, with the 2025-era 4K Plus using the MT8696D, but the 4K Select using basically the same SoC as the HD version, featuring the same G310V2 GPU at 500 MHz per the Amazon Developer documentation and the same decoder block (VPU), both of which are capable of 4K video decoding. This implies that the HD vs 4K distinction is purely software-based.
The Amazon Fire Stick HD PCB devoid of its metal shielding. (Credit: electronupdate, YouTube)
After popping open the device and noting the various ICs, the NAND Flash, the Mediatek MT7902 wireless IC, the PMIC and the aforementioned SoC all have their caps popped in order to take a closer look at their dies. For reference, as one of the largest ICs, the SoC die is a mere 5.2 x 6.45 mm. The PMIC die is more interesting as usual, as this one integrates USB-PD functionality, adding quite a bit of logic to what is otherwise a fairly mundane bit of power management features.
Overall not a very surprising design, though it does tickle that thought in the back of one’s mind whether it could be turned into a ‘4K stick’ with a few software tweaks, or perhaps more simply by installing plain Android onto its 8 GB of eMMC.
Paper as a substrate for electronic circuits is not very common, but promising for flexible circuits with low cost and easy recyclability. That said, paper is not an easy material to work with when printing traces, as the cellulose material is both absorbent and irregular, limiting the resolution and accuracy of so-called papertronics. Even when using higher-quality paper with wax-based masks this resulted in poor resolution issues, so [Zahra Rafiee] et al. opted to approach the problem from the other direction, by using hydrophobic parchment paper as the base combined with a laser.
