Dial-Up Is Still, Just Barely, A Thing

In an era dominated by broadband and wireless cellular networks, it might come as a surprise to many that dial-up internet services still exist in the United States. This persistence is not a mere relic of nostalgia — but a testament to the diverse and uneven nature of internet infrastructure across the country.

Yes, dial-up internet, with those screechy, crackly tones, remains a useful tool in areas where modern, high-speed internet services are either unaffordable or unavailable. Subscriber numbers are tiny, but some plough on and access the Internet by the old ways, not the new.

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Walking And Talking Through The UK National Museum Of Computing

I found myself in Milton Keynes, UK, a little while ago, with a few hours to spare. What could I do but rock over to the National Museum of Computing and make a nuisance of myself? I have visited many times, but this time, I was armed with a voice recorder and a mission to talk to everybody who didn’t run away fast enough. There is so much to see and do, that what follows is a somewhat truncated whistle-stop tour to give you, the dear readers, a flavour of what other exhibits you can find once you’ve taken in the usual sights of the Colossus and the other famous early machines.

A VT01 terminal showing "the adventure" game running
Click this image to play in your browser.

We expect you’ve heard of the classic text adventure game Zork. Well before that, there was the ingeniously titled “Adventure”, which is reported to be the first ‘interactive fiction’ text adventure game. Created initially by [Will Crowther], who at the time was a keen cave explorer and D & D player, and also the guy responsible for the firmware of the original Arpanet routers, the game contains details of the cave systems of Mammoth and Flint Ridge in Kentucky.

The first version was a text-based simulation of moving around the cave system, and after a while of its release onto the fledgling internet, it was picked up and extended by [Don Woods], and the rest is history. If you want to read more, the excellent site by [Rick Adams] is a great resource that lets you play along in your browser. Just watch out for the dwarfs. (Editor’s note: “plugh“.) During my visit, I believe the software was running on the room-sized ICL2966 via a VT01 terminal, but feel free to correct me, as I can’t find any information to the contrary.

A little further around the same room as the ICL system, there is a real rarity: a Marconi TAC or Transistorised Automatic Computer. This four-cabinet minicomputer was designed in the late 1950s as a ‘fast real-time computer’, is one of only five made, and this example was initially installed at Wylfa nuclear power station in Anglesey, intended as a monitoring and alarm system controller. These two machines were spare units for the three built for the Swedish air defence system, which were no longer required. Commissioned in 1968, this TAC ran continuously until 2004, which could make it one the longest continuously running computers in the world. The TAC has 4 kwords of 20-bit core memory, a paper tape reader for program loading and a magnetic drum storage memory. Unusually, for this period, the TAC has a micro-coded CISC architecture, utilising a whole cabinet worth of diode-matrix ROM boards to code the instruction set. This enabled the TAC to have a customizable instruction set. As standard, the TAC  shipped with trigonometric and other transcendental functions as individual instructions. This strategy minimized the program size and allowed more complex programs to fit in the memory.

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Avi Loeb And The Interstellar Lottery

Except for rare occasions, I don’t play the lottery. Like many of you, I consider state-run lotteries to be a tax paid only by people who can’t do math. That’s kind of arrogant coming from a guy who chose to go into biology rather than engineering specifically because he’s bad at math, but I know enough to know that the odds are never in your favor, and that I’d rather spend my money on just about anything else.

But I’m beginning to get the feeling that, unlike myself and many others, Harvard professor Avi Loeb just might be a fan of playing the lottery. That’s not meant as a dig. Far from it. In fact, I readily concede that a physicist with an endowed chair at Harvard working in astrophysics knows a lot more about math than I do. But given his recent news splashes where he waxes on about the possibility that Earth has been treated to both near misses and direct hits from interstellar visitors, I’m beginning to think that maybe I’m looking at the lottery backward.

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NASA Found Another Super Earth With Tantalizing Possibilities

Earth is a rather special place, quite unlike the other planets in the solar system. It’s nestled at the perfect distance from the sun to allow our water to remain liquid and for life to flourish in turn. It’s a rare thing; most planets are either too close and scorching hot, or too far and freezing cold.

NASA is always on the hunt for planets like our own, and recently found a new super-Earth by the name of TOI-715b. The planet is larger than our own, but it’s position and makeup mean that it’s a prime candidate for further study. Let’s take a look at how NASA discovered this planet, and why it’s special.

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Air Canada’s Chatbot: Why RAG Is Better Than An LLM For Facts

Recently Air Canada was in the news regarding the outcome of Moffatt v. Air Canada, in which Air Canada was forced to pay restitution to Mr. Moffatt after the latter had been disadvantaged by advice given by a chatbot on the Air Canada website regarding the latter’s bereavement fare policy. When Mr. Moffatt inquired whether he could apply for the bereavement fare after returning from the flight, the chatbot said that this was the case, even though the link which it provided to the official bereavement policy page said otherwise.

This latter aspect of the case is by far the most interesting aspect of this case, as it raises many questions about the technical details of this chatbot which Air Canada had deployed on its website. Since the basic idea behind such a chatbot is that it uses a curated source of (company) documentation and policies, the assumption made by many is that this particular chatbot instead used an LLM with more generic information in it, possibly sourced from many other public-facing policy pages.

Whatever the case may be, chatbots are increasingly used by companies, but instead of pure LLMs they use what is called RAG: retrieval augmented generation. This bypasses the language model and instead fetches factual information from a vetted source of documentation.

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Big Chemistry: Hydrofluoric Acid

For all of the semiconductor industry’s legendary reputation for cleanliness, the actual processes that go into making chips use some of the nastiest stuff imaginable. Silicon oxide is comes from nothing but boring old sand, and once it’s turned into ultrapure crystals and sliced into wafers, it still doesn’t do much. Making it into working circuits requires dopants like phosphorous and boron to give the silicon the proper semiconductor properties. But even then, a doped wafer doesn’t do much until an insulating layer of silicon dioxide is added and the unwanted bits are etched away. That’s a tall order, though; silicon dioxide is notoriously tough stuff, largely unreactive and therefore resistant to most chemicals. Only one substance will do the job: hydrofluoric acid, or HFA.

HFA has a bad reputation, and deservedly so, notwithstanding its somewhat overwrought treatment by Hollywood. It’s corrosive to just about everything, it’s extremely toxic, and if enough of it gets on your skin it’ll kill you slowly and leave you in agony the entire time. But it’s also absolutely necessary to make everything from pharmaceuticals to cookware, and it takes some big chemistry to do it safely and cheaply.

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Ask Hackaday: What If You Did Have A Room Temperature Superconductor?

The news doesn’t go long without some kind of superconductor announcement these days. Unfortunately, these come in several categories: materials that require warmer temperatures than previous materials but still require cryogenic cooling, materials that require very high pressures, or materials that, on closer examination, aren’t really superconductors. But it is clear the holy grail is a superconducting material that works at reasonable temperatures in ambient temperature. Most people call that a room-temperature superconductor, but the reality is you really want an “ordinary temperature and pressure superconductor,” but that’s a mouthful.

In the Hackaday bunker, we’ve been kicking around what we will do when the day comes that someone nails it. It isn’t like we have a bunch of unfinished projects that we need superconductors to complete. Other than making it easier to float magnets, what are we going to do with a room-temperature superconductor? Continue reading “Ask Hackaday: What If You Did Have A Room Temperature Superconductor?”