The Secret Wattcycle LFP Battery Downgrade

After recently reviewing a Wattcycle LFP battery sent over by the manufacturer, [Will Prowse] was made aware of some disturbing changes to the internals of batteries received by regular customers. Rather than the nice protected cables, thick solid metal busbars, braided wire and excellent build quality, the units that a regular customer – got as well as the one that [Will] bought off Amazon – all feature something more akin to what you’d find in a budget LFP battery, including a wide variety of LFP cells.

With these LFP batteries generally coming in fully opaque plastic cases, it’s really hard to tell what the internals look like without either going medieval on them or using less intrusive methods such as an X-ray machine. In this case more capable braided cables were replaced with regular cables that in a test showed a much higher voltage drop compared to the braided type.

Along with all the other changes between these batteries, this makes it impossible to rely on any reviews as a customer. [Will] notes that Wattcycle isn’t alone in doing this, and makes the case for more transparent cases for LFP batteries. After all, if you can see at a glance through the transparent case what the cables and wiring looks like, what BMS is installed and even what any LEDs on said BMS PCB are doing.

There are some LFP batteries with such a transparent case already, and with some smaller LFP batteries you can even pop the top off without having to resort to very permanent levels of violence, so this is not a problem without solutions. From a consumer perspective it definitely would be nice to see the internals as literal transparency from the manufacturer’s side, as well as an increased ability to monitor the battery for any thermal, leakage or other issues.

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The Winners Of The 2025 Obfuscated C Code Contest

One of the most exciting challenges available to any software developer is that of writing brilliantly working code that’s so obtuse, so indecipherable, and opaque, that even its own author would struggle to grasp its inner workings after returning to it a year later. While for some this is just how they naturally write code, for others it’s part of the International Obfuscated C Coding Challenge (IOCCC), with 2025’s entrants once again showing their mettle.

The IOCCC judges entries among a range of categories, as it can be hard to otherwise quantify what is the ‘best’ entry, with ground rules limiting what the entry can entail. Generally as long as your code adheres to the C11 standard with a source size of 4,993 bytes or less and final binary size of under 2,503, is accompanied by a GNU-style Makefile and doesn’t turn a judge’s computer into a raging inferno — it should qualify.

Among the winning entries we got fun ones like ‘Most likely to shock’ by [Yusuke Endoh] which generates a Lichtenberg figure in ASCII in the terminal. There are also quite practical ones, such as the ‘Best real emulator’ winner by [Nick Craig-Wood], whose entry is a functional Game Boy emulator. Although not full-featured, it can play a range of real GB ROMs, just do not expect to get any sounds or fancy terminal-based graphics.

Powering Up A Pluggable Module From The 1948 IBM 604 Electronic Calculator

In that awkward transition phase between electromechanical accounting systems used in the 1940s and the introduction of fully digital computers we find systems such as the IBM 604 Electronic Calculator, advertised for accounting, calculating and engineering tasks. While not capable of complex instructions, loops and other advanced features, it did use an interesting modular architecture with easily swappable modules containing a vacuum tube and associated components. Recently [Ken Shirriff] took a poke at one of these and even powered it up.

This kind of pluggable system would become a staple of computer systems, as they enabled the use of modules or cards with specific functions that could be swapped and combined at will to increase system flexibility, lower costs and make repairs a snap. For the IBM 604 a total of about 1250 vacuum tubes were used, apparently all of which were found on these pluggable modules.

The module that [Ken] got his hands on has a thyratron tube, which is effectively a high current switch and rectifier. In the short demonstration video you can see it being used to switch a lamp on and off, with further details explained in the article.

Despite being rather limited in its functionality and limited by the punch card input and output speed, the IBM 604 was still a smashing commercial success with over 5600 units produced. A transistorized prototype version with 2200 transistors and 95% less power usage was created in 1954 that formed the basis for the IBM 608, the world’s first commercial all-transistorized calculator.

The 608 didn’t last too long, however, as at that point the breakneck pace of semiconductor technology meant that any newly released product was already obsolete by the time it hit the market. Despite this, fundamentals like pluggable modules would keep showing up over and over, ranging from the 1950s Bendix G-15 to even modern day systems, including PCs with pluggable RAM and expansion cards as well as mainframes where hot swapping of even entire CPU modules is just another feature.

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Discovery Of An Active Wind From The Milky Way’s Central Black Hole

One of the fun aspects of astrophysics is that much of it involves phenomena which you cannot exactly study from up close, with the supermassive black hole (SMBH) at the center of this galaxy – called Sagittarius A* (Sgr A) – being a great example. Although it’s been predicted since 1971 that black holes like Sgr A radiate energy which then pushes away nearby matter to create something akin to solar wind, this had so far not been proven. Now astronomers have discovered evidence for this emanating from Sgr A*.

Using five years worth of observations made with the Atacama Large Millimeter/Submillimeter Array (ALMA) and correlating it with other observations, a Southern Lobe of movement was identified, along with evidence for a Northern Lobe. Unlike a star where you are dealing with relatively massive quantities of matter being hurled into space, in the case of a very quiet SMBH like Sqr A* you are talking about occasional small wisps of gas of which a fraction gets turned into the radiation that then exerts pressure on the remaining gas.

It is speculated to be exactly this quiescent nature of Sgr A* that makes it so difficult to find evidence of SMBH wind, though one could also argue that having a well-fed SMBH whose event horizon rapidly expands would be fascinating from an astrophysics perspective, but less exciting for any nearby inhabited planets.

Server racks branded with Internet Archive

News Sites Are Blocking Internet Archive Over AI Scraping Fears

Especially in this era of the Internet, the role of the Internet Archive’s Wayback Machine has become increasingly essential as more and more web content vanishes into the ether or is surreptitiously altered to hide salient details. More recently a new worry has seemingly cropped up in the form of scraping of data for so-called AI systems, or at least that’s part of the excuses being offered for blocking the Wayback Machine’s web crawlers, with [Andrew Deck] and [Hanaa’ Tameez] of [Nieman Lab] detailing the impact and reasons provided.

Some news outlets like The Baltimore Banner insist that they’re only blocking the Wayback Machine crawlers because they are worried that LLM chatbots would otherwise ‘improperly cite’ the source of content, while outlets like The Atlantic have put a blanket anti-scraping policy in place. Meanwhile news outlets are generally happy to let paid commercial news archiving outlets like ProQuest and LexisNexis index their content, showing a potential financial incentive.

Whatever the reasons, the direct effect is that as content is modified or vanishes during for example a system migration, buy-out or bankruptcy, researchers who rely on the Wayback Machine are pretty much forced to rely on paid offerings by ProQuest and kin, without the pure archiving focus and free access to information. It will also leave big holes in what the Wayback Machine can cover in its archives, with news especially becoming very spotty.

Incidentally there’s an ongoing petition over at SaveTheArchive.com which people can sign.

Revisiting Using AI Coding Assistants: You’re Holding It Wrong Edition

After scathing accusations of skimping on due diligence, as well as other feedback to my article on trying to use an ‘AI coding assistant’ for the first time, the only rational, academic response is to lick one’s wounds following a particularly bruising peer review and try to address the raised issues. Reality after all does not care about one’s feelings, and there may be more to this AI assistant technology that can be coaxed out with a more in-depth look.

To this end I’ll do my best to try and work through each raised point, criticism and accusation, to see what I – and perhaps others – can learn of this endeavor. Said points include the use of the wrong frontend – i.e. Copilot – and the wrong model – being Claude Haiku 4.5 – as well as the egregious flaw on my end of ‘prompting wrong’.

For the sake of due diligence the best frontend and models will be investigated for particular tasks, with finally the verbal minefield of ‘prompt engineering’ examined for industry-standard approaches.

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Repairing A Apple PowerBook 150 With Serious Issues

Sometimes you purchase an old device that is very cheap for a good reason. So too with the 1995 Apple PowerBook 150 that [Hugh Jeffreys] purchased for a single Aussie buck back in 2018. After finally taking it off the shelf recently, the issues are very apparent. Without even trying to turn it on, the visible damage ranges from the display that’s gone full vinegar with wolverine scratches, to the snapped hinge. Naturally the HDD also turned out to be dead.

Without a functioning display there was little point in continuing, so the disassembly started there, revealing many broken plastic clips. The cause of the vinegar symptom is the degrading polarizer, which with some finesse can be removed like a thick screen protector. Fortunately, here it’s put on top of the glass layer of the display, so after peeling it off the remaining glue can be safely dissolved and scraped away.

Inside the case the RTC battery was found to have started leaking, causing corrosion and damaging a variety of important traces for the keyboard and display. All of this damage seemed fixable, but after a while the damage was just too severe. Fortunately he was able to obtain a replacement for the affected daughter PCB, which allowed the display to come back to life, so that a new polarizer could be installed after cutting a large sheet down to size.

A replacement hinge was then printed in PETG and glued to the part of the lid where it had broken off, while snapped plastic clips were reinforced with glue where they had hung on. Finally, the IDE HDD was replaced with a CF card via an IDE adapter and the entire system reassembled.

Unfortunately [Hugh] wasn’t able to immediately source or create MacOS floppies with a version that the laptop wanted to install from, so that part couldn’t be tested yet, but there’s a good chance that this old PowerBook 150 has finally been cured of at least its biggest ills, without spending much more than the original asking price.

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