White LED Turning Purple: Analyzing A Phosphor Failure

May 30, 2025 by Maya Posch 32 Comments

White LED bulbs are commonplace in households by now, mostly due to their low power usage and high reliability. Crank up the light output enough and you do however get high temperatures and corresponding interesting failure modes. An example is the one demonstrated by the [electronupdate] channel on YouTube with a Philips MR16 LED spot that had developed a distinct purple light output.

The crumbling phosphor coating on top of the now exposed LEDs. (Credit: electronupdate, YouTube)

After popping off the front to expose the PCB with the LED packages, the fault seemed to be due to the phosphor on one of the four LEDs flaking off, exposing the individual 405 nm LEDs underneath. Generally, white LEDs are just UV or 405 nm (‘blue’) LEDs that have a phosphor coating on top that converts the emitted wavelength into broad band visible (white) or another specific wavelength, so this failure mode makes perfect sense.

After putting the PCB under a microscope and having a look at the failed and the other LED packages the crumbled phosphor on not just the one package became obvious, as the remaining three showed clear cracks in the phosphor coating. Whether due to the heat in these high-intensity spot lamps or just age, clearly over time these white LED packages become just bare LEDs without the phosphor coating. Ideally you could dab on some fresh phosphor, but likely the fix is to replace these LED packages every few years until the power supply in the bulb gives up the ghost.

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Forced E-Waste PCs And The Case Of Windows 11’s Trusted Platform

May 29, 2025 by Maya Posch 145 Comments

Until the release of Windows 11, the upgrade proposition for Windows operating systems was rather straightforward: you considered whether the current version of Windows on your system still fulfilled your needs and if the answer was ‘no’, you’d buy an upgrade disc. Although system requirements slowly crept up over time, it was likely that your PC could still run the newest-and-greatest Windows version. Even Windows 7 had a graphical fallback mode, just in case your PC’s video card was a potato incapable of handling the GPU-accelerated Aero Glass UI.

This makes a lot of sense, as the most demanding software on a PC are the applications, not the OS. Yet with Windows 11 a new ‘hard’ requirement was added that would flip this on its head: the Trusted Platform Module (TPM) is a security feature that has been around for many years, but never saw much use outside of certain business and government applications. In addition to this, Windows 11 only officially supports a limited number of CPUs, which risks turning many still very capable PCs into expensive paperweights.

Although the TPM and CPU requirements can be circumvented with some effort, this is not supported by Microsoft and raises the specter of a wave of capable PCs being trashed when Windows 10 reaches EOL starting this year.

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The Cost Of A Cheap UPS Is 10 Hours And A Replacement PCB

May 29, 2025 by Maya Posch 26 Comments

Recently [Florin] was in the market for a basic uninterruptible power supply (UPS) to provide some peace of mind for the smart home equipment he had stashed around. Unfortunately, the cheap Serioux LD600LI unit he picked up left a bit to be desired, and required a bit of retrofitting.

To be fair, the issues that [Florin] ended up dealing with were less about the UPS’ capability to deal with these power issues, and more with the USB interface on the UPS. Initially the UPS seemed to communicate happily with HomeAssistant (HA) via Network UPS Tools over a generic USB protocol, after figuring out what device profile matched this re-branded generic UPS. That’s when HA began to constantly lose the connection with the UPS, risking its integration in the smart home setup.

The old and new USB-serial boards side by side. (Credit: VoltLog, YouTube)

After tearing down the UPS to see what was going on, [Florin] found that it used a fairly generic USB-serial adapter featuring the common Cypress CY7C63310 family of low-speed USB controller. Apparently the firmware on this controller was simply not up to the task or poorly implemented, so a replacement was needed.

The process and implementation is covered in detail in the video. It’s quite straightforward, taking the 9600 baud serial link from the UPS’ main board and using a Silabs CP2102N USB-to-UART controller to create a virtual serial port on the USB side. These conversion boards have to be fully isolated, of course, which is where the HopeRF CMT8120 dual-channel digital isolator comes into play.

After assembly it almost fully worked, except that a Sonoff Zigbee controller in the smart home setup used the same Silabs controller, with thus the same USB PID/VID combo. Fortunately in Silabs AN721 it’s described how you can use an alternate PID (0xEA63) which fixed this issue until the next device with a CP2102N is installed

As it turns out, the cost of a $40 UPS is actually 10 hours of work and $61 in parts, although one cannot put a value on all the lessons learned here.

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Washington Consumers Gain Right To Repair For Cellphones And More

May 28, 2025 by Maya Posch 30 Comments

Starting January 1st, 2026, Washington state’s new Right to Repair law will come into effect. It requires manufacturers to make tools, parts and documentation available for diagnostics and repair of ‘digital electronics’, including cellphones, computers and similar appliances. The relevant House Bill 1483 was signed into law last week after years of fighting to make it a reality.

A similar bill in Oregon faced strong resistance from companies like Apple, despite backing another Right to Repair bill in California. In the case of the Washington bill, there were positive noises from the side of Google and Microsoft, proclaiming themselves and their products to be in full compliance with such consumer laws.

Of course, the devil is always in the details, with Apple in particular being a good example how to technically comply with the letter of the law, while throwing up many (financial) roadblocks for anyone interested in obtaining said tools and components. Apple’s penchant part pairing is also a significant problem when it comes to repairing devices, even if these days it’s somewhat less annoying than it used to be — assuming you’re running iOS 18 or better.

That said, we always applaud these shifts in the right direction, where devices can actually be maintained and repaired without too much fuss, rather than e.g. cellphones being just disposable items that get tossed out after two years or less.

Thanks to [Robert Piston] for the tip.

Fixing A Fatal Genetic Defect In Babies With A Bit Of Genetic Modification

May 27, 2025 by Maya Posch 30 Comments

Genetic defects are exceedingly common, which is not surprising considering just how many cells make up our bodies, including our reproductive cells. While most of these defects have no or only minor effects, some range from serious to fatal. One of these defects is in the CPS1 gene, with those affected facing a shortened lifespan along with intensive treatments and a liver transplant as the only real solution. This may now be changing, after the first successful genetic treatment of an infant with CPS1 deficiency.

Carbamoyl phosphate synthetase I (CPS1) is an enzyme that is crucial for breaking down the ammonia that is formed when proteins are broken down. If the body doesn’t produce enough of this enzyme in the liver, ammonia will accumulate in the blood, eventually reaching levels where it will affect primarily the nervous system. As an autosomal recessive metabolic disorder it requires both parents to be carriers, with the severity depending on the exact mutation.

In the case of the affected infant, KJ Muldoon, the CPS1 deficiency was severe with only a low-protein diet and ammonia-lowering (nitrogen scavenging) medication keeping the child alive while a search for a donor liver had begun. It is in this context that in a few months time a CRISPR-Cas9 therapy was developed that so far appears to fixing the faulty genes in the liver cells.

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Mouse Model Suggests Starch-Based Plastics Are Still Bad For You

May 26, 2025 by Maya Posch 48 Comments

To paraphrase The Simpsons: plastics are the solution to – and cause of – all of mankind’s problems. Nowhere is this more clear in the phenomenon of microplastics. Some have suggested that alternative bioplastics made out of starch could be the solution here, as the body might be able to digest and disassemble these plastic fragments better. Unfortunately, a team of Chinese researchers put this to the test using mice, with the results suggesting that starch-based plastics do not change the harm to tissues and organs.

We previously looked at this harm from micro- and nanoplastics (MNP), with humans and their brains at autopsy showing a strong correlation between disease and presence of MNPs. In this recent study mice were split up into three groups, for either no, low or high levels of these bioplastics in their food. At autopsy, the mice exposed to the bioplastics all showed damage to organs, including the same gene-regulation issues and inflammation markers as seen with other plastics.

Despite these results, researchers question how useful these results are, as they pertain to modified starches with known biodegradability issues, while starch by itself is absolutely digestible when it’s in the form of potato chips, for instance. Perhaps the trick here is to make bioplastics that are still useful as plastics, and yet as harmless to ingest as said potato chips.

Not that we recommend eating bioplastics, mind you; potato chips are definitely tastier.

NASA Is Shutting Down The International Space Station Sighting Website

May 26, 2025 by Maya Posch 35 Comments

Starting on June 12, 2025, the NASA Spot the Station website will no longer provide ISS sighting information, per a message recently sent out. This means no information on sighting opportunities provided on the website, nor will users subscribed via the website receive email or text notifications. Instead anyone interested in this kind of information will have to download the mobile app for iOS or Android.

Obviously this has people, like [Keith Cowing] over at Nasa Watch, rather disappointed, due to how the website has been this easy to use resource that anyone could access, even without access to a smart phone. Although the assumption is often made that everyone has their own personal iOS or Android powered glass slab with them, one can think of communal settings where an internet café is the sole form of internet access. There is also the consideration that for children a website like this would be much easier to access. They would now see this opportunity vanish.

With smart phone apps hardly a replacement for a website of this type, it’s easy to see how the app-ification of the WWW continues, at the cost of us users.