Author: Maya Posch

87 Articles

Be Wary Of Radioactive Bracelets And Similar

February 26, 2020 by 26 Comments

Before you start cutting up that ‘negative ion’ health bracelet or personal massager, be aware that these are highly likely to contain thorium oxide or similar radioactive powder, as this research video by [Justin Atkin] (also embedded after the break) over at The Thought Emporium YouTube channel shows. Even ignoring the irony that thorium oxide is primarily an alpha (He+) emitter and thus not a ‘negative ion’ source (which would be beta decay, with e–), thorium oxide isn’t something you want on your skin, or inside your lungs.

These bracelets and similar items appear to embed grains of thorium oxide into the usual silicon-polymer-based bracelet material, without any measures to prevent grains from falling out over time. More dangerous are the items such as the massage wand, which is essentially a metal tube that is filled with thorium oxide powder. This is not the kind of item you want to open on your kitchen table and have it spill everywhere.

Considering that these items are readily available for sale on Amazon, EBay and elsewhere, giving items like these a quick check with the ol’ Geiger counter before ripping them open or cutting them up for a project seems like a healthy idea. Nobody wants to cause a radiological incident in their workshop, after all.

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Introducing The XFM2: A New FM Synthesizer Board

February 22, 2020 by 26 Comments

[René Ceballos] contacted us about the new XFM2 FM synthesizer board, successor to the XFM that we covered on Hackaday last year. In addition to changing FPGAs from a Spartan 6 to an Artix-7 35, the DAC was also upgraded from 16 to 24 bits. Since the project is based around two easily available boards for the FPGA and DAC functionality, it is something that should be easy for anyone to recreate.https://images.squarespace-cdn.com/content/v1/5d2c7309e3281e0001ef5655/1580208742008-DDG6FHLVST9DTOU5YDV7/ke17ZwdGBToddI8pDm48kIzPiMR3_Rs2gge4hyoameUUqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKc8LXFP3nIOov1DiYlxUpn2kjauiJB9jSbs9pkYnnzvQkOGqqUmgmVAUPjW85v7F78/xfm2.PNG?format=1500w

The project consists of a lower board that features the opto-isolated MIDI-input port, a 24LC1025 EEPROM, and a few passives, on top of which are mounted the Adafruit UDA1334A-based I2S decoder board and a Digilent Cmod A7-35T, containing the Xilinx XC7A35T-1CPG236C Artix-7 FPGA. [René] has made a schematic and BOM available on the XFM2 page. Total part cost should be about $99.

A user manual, installation guide, and the binaries that have to be loaded into the FPGA – using the provided instructions – are all made available. Unfortunately no HDL source is provided, but that shouldn’t take away from the fun of assembling an FM synthesizer board like this.

[René ] said that based on the feedback to the XFM project, he is now working on a visual user interface for the board. Once this is all working and depending on the feedback from XFM2 users, he may decide to start a crowdfunding campaign.

Nuclear Fusion Power Without Regular Tokamaks Or Stellarators

February 12, 2020 by 120 Comments

When it comes to nuclear fusion, the most well-known reactor type today is no doubt the tokamak, due to its relatively straight-forward concept of plasma containment. That’s not to say that there aren’t other ways to accomplish nuclear fusion in a way that could conceivably be used in a commercial power plant in the near future.

As we covered previously, another fairly well-known type of fusion reactor is the stellarator, which much like the tokamak, has been around since the 1950s. There are other reactor types from that era, like the Z-pinch, but they seem to have all fallen into obscurity. That is not to say that research on Z-pinch reactors has ceased, or that other reactor concepts — some involving massive lasers — haven’t been investigated or even built since then.

In this article we’ll take a look at a range of nuclear fusion reactor types that definitely deserve a bit more time in the limelight.

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Lead-Free Solder Alloys: Their Properties And Best Types For Daily Use

January 28, 2020 by 84 Comments

Lead-free solder alloys have been around for as long as people have done soldering, with sources dating back about 5,000 years. Most of these alloys were combinations like copper-silver or silver-gold and used with so-called hard soldering. That’s a technique still used today to join precious and semi-precious metals together. A much more recent development is that of soldering electronic components together, using ‘soft soldering’, which entails much lower temperatures.

Early soft soldering used pure tin (Sn), yet gradually alloys were sought that would fix issues like thermal cycling, shock resistance, electron migration, and the development of whiskers in tin-based alloys. While lead (Pb) managed to fill this role for most soldering applications, the phasing out of lead from products, as well as new requirements for increasingly more fine-pitched components have required the development of new solder alloys that can fill this role.

In this article we’ll be looking at the commonly used lead-free solder types for both hobby and industrial use, and the dopants that are used to improve their properties.

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Nuclear Fusion At 100: The Hidden Race For Energy Supremacy

January 23, 2020 by 79 Comments

It’s hardly a secret that nuclear fusion has had a rough time when it comes to its image in the media: the miracle power source that is always ‘just ten years away’.  Even if no self-respecting physicist would ever make such a statement, the arrival of commercial nuclear fusion power cannot come quickly enough for many. With the promise of virtually endless, clean energy with no waste, it does truly sound like something from a science-fiction story.

Meanwhile, in the world of non-fiction, generations of scientists have dedicated their careers to understanding better how plasma in a reactor behaves, how to contain it and what types of fuels would work best for a fusion reactor, especially one that has to run continuously, with a net positive energy output. In this regard, 2020 is an exciting year, with the German Wendelstein 7-X stellarator reaching its final configuration, and the Chinese HL-2M tokamak about to fire up.

Join me after the break as I look into what a century of progress in fusion research has brought us and where it will take us next.

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Tetraethyl Lead: The Solution To One, And Cause Of Many New Problems

January 15, 2020 by 100 Comments

From the 1920s until the 1970s, most gasoline cars in the USA were using fuel that had lead mixed into it. The reason for this was to reduce the engine knocking effect from abnormal combustion in internal combustion engines of the time. While lead — in the form of tetraethyllead — was effective at this, even the 1920s saw both the existence of alternative antiknock agents and an uncomfortable awareness of the health implications of lead exposure.

We’ll look at what drove the adoption of tetraethyllead, and why it was phased out once the environmental and health-related issues came into focus. But what about its antiknock effects? We’ll also be looking at the alternative antiknock agents that took its place and how this engine knocking issue is handled these days.

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The Barcode Revolution: Welcome To Our Automated World

January 8, 2020 by 25 Comments

Featured in many sci-fi stories as a quicker, more efficient way to record and transfer information, barcodes are both extremely commonplace today, and still amazingly poorly understood by many. Originally designed as a way to allow for increased automation by allowing computer systems to scan a code with information about the item it labels, its potential as an information carrier is becoming ever more popular.

Without the tagging ability of barcodes (and their close cousin: RFID tags), much of today’s modern world would grind to a halt. The automated sorting and delivery systems for mail and parcels, entire inventory management systems, the tracing of critical avionics and rocketry components around the globe, as well as seemingly mundane but widely utilized rapid checkout at the supermarket, all depends on some variety of barcodes.

Join me on a trip through the past, present and future of the humble barcode.

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