Finally, A Calculator For The Atomic Age!

July 7, 2017 by Jenny List 17 Comments

In the 1950s, a nuclear-powered future seemed a certainty. The public had not been made aware of the dangers posed by radioactive material, any large-scale accidents involving nuclear reactors had either been hushed up or were yet to happen, and industry and governments were anxious to provide good PR to further their aims. Our parents and grandparents were thus promised a future involving free energy from nuclear reactors in all sorts of everyday situations.

With the benefit of hindsight, we of course know how the story turned out. Windscale, Three Mile Island, Chernobyl, and Fukushima, and we’re still waiting for our atomic automobiles.

If you have a hankering for nuclear-powered domestic appliances though, all is not lost. [GH] is leading the charge towards a future of atomic energy, with a nuclear-powered calculator. It’s not quite what was promised in the ’50s, but it is nevertheless a genuine appliance for the Atomic Age. At its heart is not a 1950s-style fission reactor though, but a tritium tube. Beta particles from the tritium’s decay excite a phosphor coating on the tube’s inside wall, producing a small amount of light. This light is harvested with a solar cell, and the resulting electrical energy is stored in an electrolytic capacitor. The cell has an open-circuit voltage of 1.8 V, and the 100 μF capacitor in question stores a relatively tiny 162 μJ. From this source, a dollar store calculator can operate for about 30 sec, so there should be no hanging about with your mathematics.

We’ve brought you a tritium battery before, albeit a slightly larger one. And should you need the comforting glow of a tritium tube but not the radiation risk, how about this LED-based substitute?

Sort Out Chemical Storage For Your Shop

July 7, 2017 by Jenny List 33 Comments

There is one constant in the world of hardware hacker’s workshops, be they a private workshop in your garage or a public hackspace, and it goes something like this:

Everybody’s a safety expert in whatever it is they are working with, right up until the accident.

In other words, it is very tempting to harbour a cavalier attitude to something that either you are familiar with or the hazards of which you do not understand, and this breeds an environment in which mishaps become a distinct possibility.

As hardware people, we are familiar with basic tool safety or electrical safety. The chances are that we’ve had it drummed into us at some time in our growing up, by a lab supervisor, a workshop teacher, or a parent. That you as readers and I as writer have survived this long is testament enough to the success of that education. But what about those areas in which we may not have received such an education, those things which we either encounter rarely or seem harmless enough that their safety needn’t be our concern? Chemicals, for example: everything from glue through solvents and soldering consumables to PCB chemicals and even paint. It all seems safe enough, what could possibly go wrong? The answer to that question is probably something most of us would prefer never to find out, so it’s worth looking in to how a well-run workshop can manage its chemicals in as safe a manner as possible.

Continue reading “Sort Out Chemical Storage For Your Shop” →

How Do They Synchronize Power Stations With The Grid?

July 5, 2017 by Jenny List 58 Comments

There are probably times in every Hackaday reader’s life at which you see something and realise that the technology behind it is something you have always taken for granted but have never considered quite how it works. Where this is being written there was such a moment at the weekend, an acquaintance on an amateur radio field day posted a picture of three portable gas-powered alternators connected together and running in synchronization. In this case the alternators in question were fancy new ones with automatic electronic synchronization built-in, but it left the question: how do they do that? How do they connect a new power station to the grid, and bring it into synchronization with the line? There followed a casual web search, which in turn led to the video below the break of a bench-top demonstration.

If two AC sources are to be connected together to form a grid, they must match each other exactly in frequency, phase, and voltage. To not do so would be to risk excessive currents between the sources, which could damage them and the grid infrastructure. The video below from [BTCInstrumentation] demonstrates in the simplest form how the frequencies of two alternators can be matched, by measuring the frequency difference between them and adjusting their speed and thus frequency until they can be connected. In the video he uses neon bulbs which flash at the difference frequency between the two alternators, and demonstrates adjusting the speed of one until the bulbs are extinguished. The two alternators can then be connected, and will then act together to keep themselves in synchronization. There are further videos in which he shows us the same process using a strobe light, then demonstrates the alternators keeping themselves synchronized, and phase deviation between them.

Of course, utility employees probably do not spend their time gazing at flashing neon bulbs to sync their power stations. The same measurements are not performed by eye but by electromechanical or electronic systems with automatic control of the contactors, just as they are in the fancy electronic alternator mentioned earlier. But most of us have probably never had to think about synchronizing a set of alternators, so to see it demonstrated in such a simple manner should fill a knowledge gap even if it’s one only of idle curiosity.

Continue reading “How Do They Synchronize Power Stations With The Grid?” →

A Virtual Machine, In Google Sheets

July 5, 2017 by Jenny List 38 Comments

In the last couple of decades we have become used to the browser taking over so many of the desktop functions for which we used to rely on stand-alone software. Email clients, calendars, office suites and much more can now be found in the cloud, courtesy of the usual technology companies.

Sometimes these cloud-based alternatives to desktop software can be a little sketchy, but often they have features that might surprise you as they edge towards parity with the packages they seek to replace. Google Docs, for instance has a full-featured built-in scripting language called Apps Script, that gives your full control of a document or spreadsheet with the help of a bit of Javascript. When [Brian Steffens] saw this it piqued his interest, so of course he had to in his words “do something weird with it”. The result of his efforts is the Google Sheets Virtual Machine, a virtual computer in software using spreadsheet cells as memory, stack, and registers.

With only a 100-cell memory and dependent entirely upon the processing power available to the host browser, this machine is not likely to set the world on fire. He gives full instruction set details, there are a couple of demo programs, a Fibronacci sequence generator and a factorial generator, but its general lack of power is not really the point. Instead its value lies in an elegant demonstration for its own sake that a virtual computer can be built in the unlikeliest of places, and for those interested enough to peer into its code, some idea how that might be achieved.

[via Hacker News]

Book Review: The Art Of The Patent

July 5, 2017 by Jenny List 22 Comments

In bringing suitable illustrations to our articles, we Hackaday scribes use a variety of sources that offer images featuring permissive licences. Among the usual free image libraries there is one particularly rich source, the line drawings contained within the huge archives of patents granted by the various countries around the world. These are the illustrations used as part of the patent itself to describe the working of the patent being claimed. We use them because though the items they depict are legally protected from copying by the patents they are part of, they as part of the patents themselves are in the public domain. Thus we can easily find detailed hand drawn pictures of all kinds of technical innovations from the last couple of hundred years or so, and from time to time you as our readers reap the benefit.

The beauty in hand-rendered fonts from patent artwork, collected within the book.

If you spend a while browsing old patents through a search engine such as Google Patents, you can quickly become engrossed in these beautiful images of inventions past. Though their purpose is a functional one to convey the workings of an invention, the anonymous artists have often poured all of their skill into rendering them as considerably more than mere draughtsmanship. In those dusty Government archives lurk masterpieces, just waiting to be found.

It seems we here at Hackaday are not alone in sharing a fascination with these images, for a US patent agent, [Kevin Prince], wrote a fascinating exploration of the medium in his book, The Art of the Patent. Continue reading “Book Review: The Art Of The Patent” →

London Gatwick Airport Closes Runway In Alleged Drone Strike

July 4, 2017 by Jenny List 118 Comments

London is one of those cities with an identity problem when it comes to airports. There is no one London airport, instead a group of airports serve the city at various distances from it. London Gatwick is the second largest of these, and sits with its single runway in the Sussex countryside about 30 miles south of the city.

If you follow British news sources, you may have heard a little about Gatwick in the last couple of days. Its runway was closed for two short periods and a selection of flights were diverted, because of what is being reported as a drone sighting. This is an extremely serious matter, responsible multirotor owners will be painfully aware of the distance and altitude regulations surrounding flights near airports.

An oft-shared drone identification guide for airline pilots, of uncertain provenance. — An oft-shared drone identification guide for airline pilots, of uncertain provenance (phantompilots.com).

If you are familiar with the way that drone stories are reported by the mass media, you will probably not need to click on the link above to the BBC reporting to find out its tone. There is significant concern within the multirotor community that it presents a very one-sided view, and takes at face value the assertion that the sighting was a drone, when in fact there is no proof at all of that being the case. For those of us who have seen many such stories come and go it is difficult not to agree with the drone pilots, there is at best some lazy reporting in the air, and at worst some outright journalistic irresponsibility.

As Hackaday readers, you are used to writers with an in-depth knowledge of the subjects upon which they write. We don’t know all possible facets of technology and we occasionally get things wrong, but we all have very strong backgrounds in the tech, hacker, and maker industries and communities we write about. We have engineering education, we’ve worked in a wide variety of technology industries, we build our own stuff for fun, and we’ve founded and run hackspaces.

By comparison the journalists whose work you will read in the mainstream media are generalists. They will have a specific educational background and a particular set of interests, but in their work they cover whatever stories tumble off the endless conveyor belt of events. Thus when a drone story appears, they find themselves out of their normal comfort zone of politics or local news, and can not rely on their experience to inform their coverage of it. The responsible journalistic approach is to do a little research and ask the pertinent questions asking for concrete proof of drone involvement. We’re still waiting for that to happen in these allege drone encounters.

Multirotor building and flying is a significant feature of our community, and anything that brings the attention of law enforcement to the kind of work we do should be a worry to us all. Multirotors are not the only things covered by Hackaday that could be misrepresented in the same way. We’ve visited this topic before, take a look at our analysis of a series of air proximity reports blamed on drones. Some of them, you couldn’t make up.

Gatwick airport image: Andre Wadman [GFDL 1.2].

Something To Think About While You’re Mowing The Lawn

June 29, 2017 by Jenny List 90 Comments

Well here we are, we’ve reached that time of year again at which our yearly ritual of resuscitating small internal combustion engines from their winter-induced morbidity is well under way. It’s lawn mowing season again, and a lot of us are spending our Saturday afternoons going up and down our little patches of grass courtesy of messers Briggs and Stratton. Where this is being written, the trusty Honda mower’s deck has unexpectedly failed, so an agricultural field topper is performing stand-in duty for a while, and leaving us with more of the rough shag pile of a steeplechaser’s course than the smooth velvet of a cricket ground. Tea on the lawn will be a mite springier this year.

When you think about it, there’s something ever so slightly odd about going to such effort over a patch of grass. Why do we do it? Because we like it? Because everyone else has one? Or simply because it’s less effort to fill the space with grass than it is to put something else there? It’s as if our little pockets of grassland have become one of those facets of our consumer culture that we never really think about, we just do. Continue reading “Something To Think About While You’re Mowing The Lawn” →