These days, it is hard to imagine electronics without printed circuit boards. They are literally in everything. While making PCBs at home used to be a chore, these days, you design on a computer, click a button, and they show up in the mail. But if you go back far enough, there were no PC boards. Where did they come from? That’s the question posed by [Steven Leibson] who did some investigating into the topic.
There were many false starts at building things like PCBs using wires glued to substrates or conductive inks. However, it wasn’t until World War II that mass production of PC boards became common. In particular, they were the perfect solution for proximity fuzes in artillery shells.
Most of us would equate commercial airline travel with fixed-wing aircraft, but civilian transport by helicopter, especially in large and sparsely populated regions, is common enough. It was once even big business in the Soviet Union, where the Aeroflot airline operated passenger helicopters in regular service for many decades. In the mid-1960s they even started work on converting the Mil Mi-6 — the USSR’s largest and fastest helicopter — to carry paying passengers. Unfortunately this never got past a single prototype, with the circumstances described by [Oliver Parken] in a recent article.
This passenger version of the Mi-6 got the designation Mi-6P (for passazhirskyi, meaning passenger) and would have seated up to 80 (3 + 2 row configuration), compared to the Mi-8 passenger variant that carried 28 – 31 passengers. Why exactly the Mi-6P never got past the prototype stage is unknown, but its successor in the form of the Mi-26P has a listed passenger variant and features. Both have a cruising speed of around 250 km/h, with a top of 300 km/h. The auxiliary winglets of the Mi-6 provided additional lift during flight, and the weight lifting record set by the Mi-6 was only broken by the Mi-26 in 1982.
An obvious disadvantage of passenger helicopters is that they are more complicated to operate and maintain, while small fixed wing airliners like the ATR 72 (introduced in 1988) can carry about as many passengers, requires just a strip of tarmac to land and take off from, travel about twice as fast as an Mi-6P would, and do not require two helicopter pilots to fly them. Unless the ability to hover and land or take-off vertically are required, this pretty much explains why passenger helicopters are such a niche application. Not that the Mi-6P doesn’t have that certain je ne sais quoi to it, mind.
Throughout history, clean and potable water has been one of the most prized possessions, without which no human civilization could have ever sustained itself. Not only is water crucial for drinking and food preparation, but also for agriculture, cleaning and the production of countless materials, chemicals and much more. And this isn’t a modern problem: good water supplies and the most successful ancient cultures go hand in hand.
For instance, the retention and management of fresh water in reservoirs played a major role in the Khmer Empire, with many of its reservoirs (baray) surviving to today. Similarly, the Anuradhapure Kingdom in Ceylon (now Sri Lanka) featured massive reservoirs like Kala Wewa that was constructed in 460 CE with a capacity of 123 million m3. In the New World, the Maya civilization similarly created reservoirs with intricate canals to capture rainwater before the dry season started, as due to the karst landscape wells were not possible.
Keeping this water fresh and free from contaminants and pollution was a major problem for especially the Maya, with a recent perspective by Lisa J. Lucera in PNAS Anthropology suggesting that they used an approach similar to modern day constructed wetlands to keep disease and illness at bay, while earlier discoveries also suggest the use of filtration including the use of zeolite.
Until the 1970s, a very common method to dispose of unneeded munitions was to simply tip them off the side of a ship. This means that everything from grenades to chemical weapons have been languishing in large quantities around Europe’s shorelines, right alongside other types of unexploded ordnance (UXO).
Although clearing and mapping such dump sites are a standard part of e.g. marine infrastructure such as undersea cabling and off-shore wind turbines, no large-scale effort has so far been undertaken to remove them, even as they continue to pose an increasing hazard to people and the environment. Most recently, efforts are underway to truly begin clearing these UXO, as the BBC reports.
Although it’s often said that the era of ocean liners came to an end by the 1950s with the rise of commercial aviation, reality isn’t quite that clear-cut. Coming out of the troubled 1940s arose a new kind of ocean liner, one using cutting-edge materials and propulsion, with hybrid civil and military use as the default, leading to a range of fascinating design decisions. This was the context in which the SS United States was born, with the beating heart of the US’ fastest battle ships, with light-weight aluminium structures and survivability built into every single aspect of its design.
Outpacing the super-fast Iowa-class battleships with whom it shares a lot of DNA due to its lack of heavy armor and triple 16″ turrets, it easily became the fastest ocean liner, setting speed records that took decades to be beaten by other ocean-going vessels, though no ocean liner ever truly did beat it on speed or comfort. Tricked out in the most tasteful non-flammable 1950s art and decorations imaginable, it would still be the fastest and most comfortable way to cross the Atlantic today. Unfortunately ocean liners are no longer considered a way to travel in this era of commercial aviation, leading to the SS United States and kin finding themselves either scrapped, or stuck in limbo.
In the case of the SS United States, so far it has managed to escape the cutting torch, but while in limbo many of its fittings were sold off at auction, and the conservation group which is in possession of the ship is desperately looking for a way to fund the restoration. Most recently, the owner of the pier where the ship is moored in Philadelphia got the ship’s eviction approved by a judge, leading to very tough choices to be made by September.
One of the joys of the UK’s Electromagnetic Field hacker camp lies in the junk table, where trash turns to treasure in the blink of an eye. This year I returned relatively unscathed from my few days rifling through the tables,but I did snag a few pieces. One of them is a wired telephone, which would be a fairly unremarkable find were it not for its flip-up LCD screen and QWERTY keyboard.
My prize is a 2002 Amstrad E-m@iler Plus, one of a series of internet-equipped telephones from the British budget electronics company. The device itself and the story behind it make for a fascinating tale of a dotcom-era Internet flop, and a piece of hardware that could almost tempt today’s hackers.
You’ve Heard Of The Dotcom Boom, But Have You Heard Of The Hardware?
In the late 1990s, everything was about the Internet, but seemingly few outside the kind of people who read Hackaday really understood what it was really about. I’ve written before on these page about how hype blinded the CD-ROM industry to the shortcomings of its technology, but while that had in reality only gripped the publishing business, the Internet hype which followed had everyone in its thrall. You’re probably familiar with the story of the dotcom boom and crash as startup companies raised millions on shaky foundations before folding when they couldn’t deliver, but in parallel with that there was also a parallel world for hardware. The future was going to be connected, but on what and whose hardware would that connection happen? Continue reading “The Amstrad E-m@iler, The Right Product With The Wrong Business Model”→
It is funny how sometimes things you think are bad turn out to be good in retrospect. Like many of us, when I was a kid, I was fascinated by science of all kinds. As I got older, I focused a bit more, but that would come later. Living in a small town, there weren’t many recent science and technology books, so you tended to read through the same ones over and over. One day, my library got a copy of the relatively recent book “The Amateur Scientist,” which was a collection of [C. L. Stong’s] Scientific American columns of the same name. [Stong] was an electrical engineer with wide interests, and those columns were amazing. The book only had a snapshot of projects, but they were awesome. The magazine, of course, had even more projects, most of which were outside my budget and even more of them outside my skill set at the time.
If you clicked on the links, you probably went down a very deep rabbit hole, so… welcome back. The book was published in 1960, but the projects were mostly from the 1950s. The 57 projects ranged from building a telescope — the original topic of the column before [Stong] took it over — to using a bathtub to study aerodynamics of model airplanes.
X-Rays
[Harry’s] first radiograph. Not bad!However, there were two projects that fascinated me and — lucky for me — I never got even close to completing. One was for building an X-ray machine. An amateur named [Harry Simmons] had described his setup complaining that in 23 years he’d never met anyone else who had X-rays as a hobby. Oddly, in those days, it wasn’t a problem that the magazine published his home address.
You needed a few items. An Oudin coil, sort of like a Tesla coil in an autotransformer configuration, generated the necessary high voltage. In fact, it was the Ouidn coil that started the whole thing. [Harry] was using it to power a UV light to test minerals for flourescence. Out of idle curiosity, he replaced the UV bulb with an 01 radio tube. These old tubes had a magnesium coating — a getter — that absorbs stray gas left inside the tube.
