Dream Team Members Announced for the 2020 Hackaday Prize

The Dream Team program is an exciting new element of the 2020 Hackaday Prize, with twelve people accepted to work full-time on a specific problem for each of our non-profit partners this summer. Each team of three is already deep into an engineering sprint to pull together a design, and to recognize their efforts, they’ll be receiving a $3,000 monthly microgrant during the two-month program.

Join us after the break to meet the people that make up each of the teams and get a taste of what they’re working on. We’ll be following along as they publish detailed work logs on the Dream Team project pages.

Conservation X Labs Dream Team

Erin “RobotGrrl” Kennedy, Oluwatobi Oyinlola, and Leonardo Ward have been selected for the Conservation X Labs Dream Team. Erin is the technical founder of Robot Missions, recently completed the Space Studies Program at the International Space University, and is from Ontario, Canada. Oluwatobi is an Embedded Systems Engineer, Inventor, and IoT Evangelist from Ibada, Nigeria. Leonardo is an electronics engineer who works on future technologies and lives in La Guaira, Venezuela.

Together they are working on the challenge of reducing ghost gear in the world’s oceans, the equipment from fishing and maritime industries that doesn’t make it back to the ship and remains in the environment as pollution.

Field Ready Dream Team

Antonio Anaya, Meesha Gupta, and Thomas Hartley have been selected for the Field Ready Dream Team. Antonio has experience adapting methodologies and tools for use in remote and difficult environments, and lives in Tuxtla Gutierrez, Mexico. Meesha is an electrical engineer who’s worked on building prosthetic arms and lives in Schenectady, New York. Tom is a design engineer with backgrounds in computer science and electronics who lives in London, UK.

Together they are working on the challenge of ensuring quality control of distributed manufacturing processes. When developing on-site manufacturing in remote areas and disaster relief situations, a feedback loop for what worked and what didn’t will multiply the effectiveness of the efforts.

CalEarth Dream Team

Sameera Chukkapalli, Jason Knight, and Alex Whittemore have been selected for the CalEarth Dream Team. Sameera is an advanced architect and director of Needlab in Barcelona, Spain. Jason is a product designer interested in biological fabrication and design who lives in Eindhoven, Netherlands. Alex is an electronics engineer with expertise in design for manufacture who lives in Manhattan Beach, California.

Together they are working on the challenge of automating parts of the building process for SuperAdobe housing. The labor that goes into the earthen building system is the most expensive and time-consuming part of this building process, and any efficiency gain means more housing at reduced time and expense.

United Cerebral Palsy of Los Angeles Dream Team

Kelvin Chow, Ruben Kackstaetter, and Nataliya Kosmyna have been selected for the UCPLA Dream Team. Kelvin is a mechanical and biomedical engineer from Toronto, Canada. Ruben is an embedded software engineer with a background in electrical engineer who lives in Frederick, Colorado. Nataliya is an MIT researcher and entrepreneur with a Ph.D in computer science who lives in Boston, Massachusetts.

Together they are working on the challenge of designing a new type of universal remote to meet the needs of physically challenged individuals. One-off accessibility devices are surprisingly expensive and require specialized skills to integrate into everyday life. This dream team will work to break down barriers of cost and usability for people living with a range of physical challenges.

We Want to See Your Projects in the Hackaday Prize!

Congratulations to all of the Dream Team members, it’s exciting to see people from all over the world come together to work on the challenge. Of course that’s the point of the Hackaday Prize, and we want to see everyone spending some cycles to tackle hard problems.

You have until August 31st to submit your own entry in any of the challenge categories of the 2020 Hackaday Prize. You’ll be solving real-world issues highlighted by this year’s non-profit partners, and be in the running for a $50,000 grand prize and nine other top prizes. We can’t wait to see what you’re working on!

Posted in 2020 Hackaday Prize, Dream Team challenge, The Hackaday Prize | Leave a comment

How Early Radio Receivers Worked

If you’ve ever built a crystal radio, there’s something magical about being able to pull voices and music from far away out of thin air. If you haven’t built one, maybe you should while there’s still something on the AM band. Of course, nowadays the equivalent might an SDR. But barring a computer solution, there are not many ways to convert radio waves into intelligence. From a pocket radio to advanced RADAR to a satellite in orbit, receiving a radio wave is accomplished in pretty much the same way.

There are, however, many ways to modulate and demodulate that radio wave. Of course, an AM radio works differently than an FM radio. A satellite data downlink works differently, too. But the process of capturing the radio wave from the air and getting them into a form ready for further processing hasn’t changed much over the years.

In this article, I’ll talk about the most common radio receiver architectures you may have seen in years past, and next week I’ll talk about modern architectures. Either way, understanding receiver architectures will help you design new radios or troubleshoot them.

Comparing Radios

If you were going to grade a receiver, there are several things that are of prime importance:

  • Selectivity – There are lots of radio waves swimming around you. A selective receiver can pull out just the one you want. This is particularly noticeable when you have two strong stations near each other in frequency.
  • Sensitivity – The signal coming in from an antenna is probably very weak. Receivers have different levels of sensitivity and a more sensitive receiver will pick up a weaker signal.
  • Noise floor – Receivers will have a certain amount of noise that will cover up a weak signal. Obviously, the lower the noise floor, the better reception for weak signals.

That Crystal Radio

The crystal radio is one of the simplest of radio designs, operating without an amplifier and getting its power from the radio signal itself. The crystal radio you built as a kid is very similar in design to the earliest radio receivers. A tuned circuit picks the frequency and a detector — usually a diode — demodulates the signal directly. If you do the math, the tuned circuit has low impedance to all frequencies except the one you’ve tuned into. The coil and the capacitor effectively cancel each other out at that frequency, and — if the components were perfect — present an infinite impedance to the signal of interest. That means all other signals will attenuate compared to the main signal.

The original design of these radios date to when there was no good way to amplify signals, so it doesn’t. That means you need a strong signal and a big antenna. You also benefit from a solid ground connection. Never built a crystal radio? My favorite simulator, Falstad, has a crystal radio you can simulate. The simulation relies on the program’s antenna component which has AM modulated signals at 3 kHz, 2.71 kHz, and 2.43 kHz.

While the tank circuit offers some selectivity, it isn’t very good. The sensitivity of this receiver is also not very good. You don’t generally see circuits like this in practical applications. However, some people like to try to push the best possible performance from a crystal radio, like Chris Wendling does in the video below. If you decide to build one, you might want to start with something more modest.

TRF and Reflex

A step up from the crystal radio is the TRF or tuned radio frequency architecture. With TRF, you basically have a crystal radio with some amplifiers ahead of the detector that amplify better at some frequencies than others — essentially filters with gain.

If you’ve ever seen a 1920s- or 1930s-era radio with numerous tuning knobs on the front panel, that’s probably a TRF radio. You had to tune each dial to the correct frequency.

The TRF is not a bad design, especially if you could figure out how to change the tuning of the amplifiers from a single control. But it is on the lower end of the performance spectrum. However, many inexpensive radios still use TRF because a 1972-era chip and its successors cram an entire TRF radio into a small IC package.

The device looked like a transistor and at least one variant had 10 transistors inside. It provided the RF amplification, detection, and even automatic gain control using only six external components. The original chip expected you to have an external coil and capacitor, a few filter capacitors, and a few resistors to both power the device and provide the automatic gain control (AGC) action. Later models also had some audio amplification stages.

Obviously, one three-legged device appealed to companies that wanted to make small cheap radios. Speaking of cheaper, another old version of the TRF is the reflex receiver. It dates back to 1914, although it was independently discovered at least one other time in the early 20th century.

The idea is to use one amplifier for amplifying both RF and the audio output (see the accompanying block diagram and schematic). This is possible because the radio frequency is so much higher than the audio frequencies and you can use filters to steer the signals through the same tube. These are generally not seen much anymore, but it is an interesting solution to the days when saving a single active device was a major cost savings.

Modern Times

While you don’t see many crystal and reflex radios these days, there are still TRF designs floating around, especially based on the many ICs that work that way. However, the regenerative receiver is probably a better choice if you want to make a very simple but workable radio. There are also direct conversion receivers — you see them a lot with software defined radio setups. The gold standard is the superheterodyne receiver, which is what an overwhelming number of devices use today.

I’ll talk about those architectures, and a few others, in the next article. Meanwhile, see what you can do to build that crystal radio. If you don’t have the right parts, you can make most of them from common items. If you don’t have a diode, you could use a razor blade and a pencil, as [RimstarOrg] — the YouTube channel of Hackaday’s own Steven Dufresne — shows in the video below.

Acknowledgment: Most of the pretty pictures of block diagrams and schematics were adapted from public domain sources on Wikipedia, particularly from [Chetvorno]. What a great resource.

Posted in crystal radio, Featured, history, Original Art, radio frequency, radio hacks, receivers, reflex receiver, RF, TRF, TRF receiver, Tuned Radio Frequency | Leave a comment

Hackaday Podcast 075: 3D Printing Japanese Joinery, Android PHONK, One-Armed Time Bandit, and Whistling Bridges

Hackaday editors Mike Szczys and Elliot Williams scoop up a basket of great hacks from the past week. Be amazed by the use of traditional Japanese joinery in a 3D-printed design — you’re going to want to print one of these Shoji lamps. We behold the beautiful sound of a noise generator, and the freaky sound from the Golden Gate. There’s a hack for Android app development using Javascript on an IDE hosted from the phone as a webpage on your LAN. And you’ll like the KiCAD trick that makes enclosure design for existing boards a lot easier.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (~65 MB)

Places to follow Hackaday podcasts:

Episode 075 Show Notes:

New This Week:

  • How do you get a foam airplane out of a 35 m tall tree?

Interesting Hacks of the Week:

Quick Hacks:

  • Mike’s Picks:
  • Elliot’s Picks:

Can’t-Miss Articles:

Posted in Golden Gate Bridge, Hackaday Columns, joinery, n64, podcast, Podcasts, project box, Shoji Lantern | Leave a comment

Steampunk Geiger Counter is a Mix of Art and Science

It took nearly a year for [Chris Crocker-White] to assemble this glorious mahogany and brass Geiger counter, but we think you’ll agree with us that it was time well spent. From the servo-actuated counter to the Nixie tubes and LED faux-decatrons, this project is an absolute love letter to antiquated methods of displaying information. Although for good measure, the internal Raspberry Pi also pushes all the collected radiation data into the cloud.

[Chris] says the design of this radiation monitor was influenced by his interest in steampunk and personal experience working on actual steam engines, but more specifically, he also drew inspiration from a counter built by [Richard Mudhar].

Based on a design published in Maplin back in 1987, [Richard] included a physical counter and LED “dekatron” displays as an homage to a 1960s era counter he’d used back in his school days. [Chris] put a modern spin on the electronics and added the glowing display of real-time Counts Per Minute (CPM) as an extra bonus; because who doesn’t like some Nixies in their steampunk?

Internally, the pulses generated by a common Geiger counter board are picked up by some custom electronics to drive the servo and LEDs. Triggered by those same pulses, the Raspberry Pi 3A+ updates the Nixie display and pushes the data out to the cloud for analysis and graphing. Note that the J305β Geiger tube from the detector has been relocated to the outside of the machine, with two copper elbows used as connectors. This improves the sensitivity of the instrument, but perhaps even more importantly, looks awesome.

We’ve seen some very high-tech DIY radiation detection gear over the years, but these clever machines that add a bit of whimsy to the otherwise mildly terrifying process of ionizing radiation are always our favorite.

Posted in classic hacks, dekatron, geiger counter, ionizing radiation, nixie tube, steampunk | Leave a comment

This Week in Security: F5, Novel Ransomware, Freta, and Database Woes

The big story of the last week is a problem in F5’s BIG-IP devices. A rather trivial path traversal vulnerability allows an unauthenticated user to call endpoints that are intended to be restricted to authenticated. That attack can apparently be as simple as:

 'https://[F5 Host]/tmui/login.jsp/..;/tmui/locallb/workspace/tmshCmd.jsp?command=list+auth+user+admin'

A full exploit has been added to the metasploit framework. The timeline on this bug is frighteningly quick, as it’s apparently being actively exploited in the wild. F5 devices are used all over the world, and this vulnerability requires no special configuration, just access to the opened management port. Thankfully F5 devices don’t expose the vulnerable interface to the internet by default, but there are still plenty of ways this can be a problem.

Freta

Microsoft has made a new tool publicly available, Freta. This tool searches for rootkits in uploaded memory snapshots from a Linux VM. The name, appropriately, is taken from the street where Marie Curie was born.

The project’s namesake, Warsaw’s Freta Street, was the birthplace of Marie Curie, a pioneer of battlefield imaging.

The impetus behind the project is the realization that once a malicious actor has compromised a machine, it’s possible to compromise any security software running on that machine. If, instead, one could perform a security x-ray of sorts, then a more reliable conclusion could be reached. Freta takes advantage of the VM model, and the snapshot capability built into modern hypervisors.

As you might imagine, the idea of sending snapshots of your Linux VMs to Microsoft for scanning has been met with some skepticism. That said, the primary use case for Freta will likely be the Azure cloud, so it’s reasonable to see this as just another tool for that ecosystem. It will be interesting to see this technology mature, as there seems to be great potential.

Vulnerability Compatibility in IE11

Earlier in the year, yet another jscript.dll vulnerability was found and fixed in Internet Explorer. As a quick recap, jscript.dll is the javascript engine from IE8. The continual presence of IE8 compatibility mode means that this old codebase still persists in modern Windows versions. Were IE8 only accessible by user intervention, this would be much less of an issue, but a website can request this compatibility mode, meaning that simply visiting a malicious website could enable an attack.

What we have this week is a detailed look at CVE-2020-1062, the bug in question. It’s a use after free, and it’s triggered by freeing an object in an overridden callback of that object. In the example code, the exploit defines the “toString” function, and manages to free the parent object in that function. As is almost always the case, finding a crash is the easy part, but turning it into a working exploit is much harder. The use-after-free bug doesn’t in itself allow for code execution, but results in code execution jumping to a location controlled by the attacker. Using the Binary Ninja tool, the researchers found an existing function that they could jump to, and from there pull off remote code execution. The full story is more involved than we have space here to cover, so go check it out for the full details.

Citrix Bug Detailed

Earlier this year, we covered CVE-2019-19781, another path transversal vulnerability, but this one is in Citrix products. Now, six months have passed since the initial disclosure, and Mikhail Klyuchnikov has written up a more detailed report on the flaw.

At it’s core, the vulnerability is simple. On a Citrix gateway, “/vpn/” hosts the login page for remote users. The url isn’t properly sanitized, so something like: /vpn/../vpns/portal/scripts/[scriptName].pl
doesn’t require authentication, but does actually execute the Perl script at the given location. The ability to interact directly with these scripts as an unauthenticated user would be problem enough, but the newbm.pl script actually allows writing data to arbitrary locations. Between the ability to execute Perl scripts, and the ability to write to the file system, it’s rather trivial to install a remote shell using this vulnerability.

Ransomware Hitchhikes on USB Drives

Try2cry is a new ransomware, spreading itself through USB flash drives. In the old days, this sort of worm would simply use the autorun feature of Windows to automatically infect a machine when plugged in. On modern machines, with autorun disabled, malware authors have to be more creative in order to spread their wares. Try2cry copies it’s installer to the root of the flash drive, marks all the existing files and folders as hidden, and then creates shortcuts in place of the hidden files. These shortcuts all point back to the malware installer, and the hope is that a user won’t notice the change, and installs the malware when trying to access the files.

Apparently this ransomware is little more than a copy-and-paste of the open source “stupid” ransomware, available on GitHub. The good news is that it can be decrypted with available tools.

MongoDB Ransomware

Yes, even more ransomware. MongoDB databases are quite popular, with something like 45,000 of them exposed to the internet. The problem is that half of those are configured without a password. Anyone can connect to, read, and write to them. Yes, many of those are probably just for testing, but inevitably some of them have live data as well. Apparently some aspiring blackhat realized that all those unprotected databases were a prime target, and launched an attack.

Each database is wiped, and a ransomware note is added in place. As far as ransomware goes the .015 BTC that is requested is rather cheap, valued at $138 at time of writing. The worst part of the attack might be the threat attached: to leak the stolen data, and then file a GDPR complaint on behalf of those whose data was exposed.

And Finally…

Samba announced a pair of bugs recently. So far, it appears that neither problem can lead to RCE, but they’re rather simple to launch DoS attacks. One attack is a variation on the zip bomb, where a DNS name composed of 8127 dots causes Samba to lose it’s mind. The other flaw is a code softlock triggered by a UDP packet with an empty data message. Both flaws require netbios to be enabled in an Active Directory configuration.

IBM’s Db2 database software has a remotely exploitable buffer overflow. This issue can result in arbitrary code execution as root, so make sure to get this patched if you’re running big blue.

Posted in Hackaday Columns, news, ransomware, security hacks, This Week in Security, vulnerabilities | Leave a comment

Tablet Oscilloscope Claims 100 MHz, But Is It?

[LearnElectronics] grabbed a FNIRSI tablet oscilloscope from a vendor from China. The device has a seven-inch touchscreen and claims to be a two-channel 100 MHz scope. But is it? Watch the video below and you’ll see.

Spoiler alert: [LearnElectronics] was skeptical of the 100 MHz claim and it looks like it is more like a 30 MHz analog bandwidth. Despite that, it does seem like a pretty capable 30 MHz scope in a very handy form factor and a very cheap price: as little as $120 or so, depending on where you shop.

The test setup was a bunch of can oscillators and up to about 30 MHz, the scope did OK. After that, the results were less than stellar. However, we aren’t sure that the test setup — on a solderless breadboard — wasn’t part of the problem and we’d have liked to see the test done with some known good quality probes as that can also contribute to bad readings even if the scope’s circuitry is up to par. We’ve seen reviews of these cheap probes that suggest they aren’t bad, but they aren’t actually all they claim, either.

The verdict? [LearnElectronics] likes it for a 30 MHz cheap scope. Of course, cheap is a relative term here. You can get a much better scope, but it will probably cost more than this one. For most of what you are probably doing with a scope, this seems like it would be adequate. On the other hand, throw in a few hundred extra dollars and you could have more channels, a more likely chance of measuring high-frequency signals, and probably enhanced measurement capabilities, too.

We will admit, though, having a portable battery-operated scope can be super handy sometimes, and you don’t always need the highest speed. You probably use your cheap multimeter more than your six and a half digit bench scope, too, right?

While the screen isn’t large, it is more convenient than a tube full of flames. And while it may not quite make 100 MHz, it is cheaper than one that will do 100 GHz.

Posted in oscilloscope, tool hacks | Leave a comment

Video: Bil Herds Looks at Mitosis

I loved my science courses when I was in Junior High School; we leaned to make batteries, how molecules combine to form the world we see around us, and basically I got a picture of where we stood in the  scheme of things, though Quarks had yet to be discovered at the time.

In talking with my son I found out that there wasn’t much budget for Science learning materials in his school system like we had back in my day, he had done very little practical hands-on experiments that I remember so fondly. One of those experiments was to look and draw the stages of mitosis as seen under a Microscope. This was amazing to me back in the day, and cemented the wonder of seeing cell division into my memory to this day, much like when I saw the shadow of one of Jupiter’s moons with my own eyes!

Now I have to stop and tell you that I am not normal, or at least was not considered to be a typical young’un growing up near a river in rural Indiana in the 60’s. I had my own microscope; it quite simply was my pride and joy. I had gotten it while I was in the first or second grade as a present and I loved the thing. It was just horrible to use in its later years as lens displaced, the focus rack became looser if that was possible, and dirt accumulated on the internal lens; and yet I loved it and still have it to this day! As I write this, I realize that it’s the oldest thing that I own. (that and the book that came with it).

Today we have better tools and they’re pretty easy to come by. I want to encourage you to do some science with them. (Don’t just look at your solder joints!) Check out the video about seeing mitosis of onion cells through the microscope, then join me below for more on the topic!

What is Mitosis?

The microscope is an excellent tool of Biology and a great place to start is by observing mitosis as it happens. Mitosis is where cells divide to make more cells so that tissue may grow. As it turns out, the tips of fresh roots on onions and garlic have rapid tissue growth in a concentrated area, making the viewing of the various stages of cell division worthwhile. In preparation for this article I started growing a shallot and an onion in a class of water and waiting for the tips to spout.

mi·to·sis /mīˈtōsəs/ noun BIOLOGY

  1. a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.

I can think of no better example of being able to see one of the complex miracles that make life possible than to look at cell division with one’s own eyes.

Scope with a Camera

My son owns a ‘scope that is much better than my old tiny clunker, yet he got it for the same price as what mine cost back in the day relatively speaking. What’s more is that I can replace one of his eyepieces with a camera and share what I see with others — you in this case. This is something I would not have ever imagined being able to do “back in my day”.

I actually have several microscopes in my hardware lab, two are dedicated to assisting with surface mount assembly, but my son’s includes up to 2000x magnification! That what I used to make these picture.

What We’re Looking For

Life based on cell division has the ability to make new copies of vital tissue cells starting with the ability of DNA to divide and replicate. As the process continues, whole chromosomes replicate by division with two new cells forming in place of the original one. Different organisms have differing numbers of chromosome by default, the onion under the scope today has 16 chromosomes arranged in 8 pairs, by default compared to the 23 pairs of a human. The number of chromosomes doesn’t necessarily imply the complexity of the organism, dogs have 78 chromosomes for example, compared to humans’ 46.

Major Events in Mitosis [Image source: NIH Science Primer]

Phases

Onion cells in different stages of mitosis [Image by Edmund B. Wilson]Some of the main phases of Mitosis are:

Prophase or the “before” phase. The cell still looks very similar to a non-replicating cell even though things are starting to happen.

Prometaphase is where the walls of the nucleus break apart and the act of cell division takes over the whole cell. This is where it really starts to be visible using this level of microscope.

Metaphase or “next to” and true to its name the chromosomes line up side by side near the center of cell as various forces pull in opposite directions. This looks cool when seen in real life.

Anaphase or “after” is when it starts to look like as new twin cells.

Telophase or “end”.  ‘nuff said.

Sliding Away

To prepare the onion tissue for observation I first soaked it in warm hydrochloric acid. If you think that that sounds like I am digesting the tissue much like our own stomachs do, you would be correct. The cells cease activity, sometimes called “fixing”. A bunch of the matter exterior to the cell walls is digested or softened, allowing us to concentrate on the contents of the cells. It also makes it easier for dye to get into the cell and to mash the tissue thin enough to see one layer of cells.

I meant to use a Feulgen stain and thought I had some. I didn’t. I ended up using Methylene Blue, an old standby and was the stain I used originally back when I was young. The slides weren’t quite as clear as I would have liked but my son still got the experience of making his own slides.

Smashing Roots

The next step is to carefully smash the softened root tissue as flat as possible in an effort to get as close to one layer of cells. Usually I break the slide cover doing this, occasionally resulting in my finger bleeding all over the slide, but today it goes almost perfectly.

With that said, there is only so much flattening the “mash method” and part of the experience in looking through the eyepiece is continuous adjustment of the focus as the subject matter still has an amount of three dimensional aspect to it.

As can be seen in the images below, we caught all of the major phases of mitosis, my onions have been sacrificed for a worthy cause.

This slideshow requires JavaScript.

Conclusion

I loved my microscope, and still do, it represented my ability to study and learn on my own and yet see way more than I could than I could without it.  It also allowed me to focus my curiosity in a hidden realm and was a early gateway in my quest for science when I was young.

Posted in bil herd, hackaday, Hackaday Columns, microscope, microscopy, science | Leave a comment

Turning a Waterjet Cutter into a Wood Lathe, For No Reason

On the shortlist of dream tools for most metalworkers is a waterjet cutter, a CNC tool that uses insanely high-pressure water mixed with abrasive grit to blast sheet metal into intricate shapes. On exactly nobody’s list is this attachment that turns a waterjet cutter into a lathe, and with good reason, as we’ll see.

This one comes to us by way of the Waterjet Channel, because of course there’s a channel dedicated to waterjet cutting. The idea is a riff on fixtures that allow a waterjet cutter (or a plasma cutter) to be used on tubes and other round stock. This fixture was thrown together from scrap and uses an electric drill to rotate a wood blank between centers on the bed of the waterjet, with the goal of carving a baseball bat by rotating the blank while the waterjet carves out the profile.

The first attempt, using an entirely inappropriate but easily cut blank of cedar, wasn’t great. The force of the water hitting the wood was enough to stall the drill; the remedy was to hog out as much material as possible from the blank before spinning up for the finish cut. That worked well enough to commit to an ash bat blank, which was much harder to cut but still worked well enough to make a decent bat.

Of course it makes zero sense to use a machine tool costing multiple hundreds of thousands of dollars to machine baseball bats, but it was a fun exercise. And it only shows how far we’ve come with lathes since the 18th-century frontier’s foot-powered version of the Queen of the Machine Shop.

Posted in carving, cnc, cnc hacks, fixture, lathe, tool hacks, turning, waterjet, wood | Leave a comment

The Simplest TS100 Upgrade Leads Down A Cable Testing Rabbit Hole

By now, I must have had my Miniware TS100 soldering iron for nearly three years. It redefined what could be expected from the decent end of the budget soldering iron spectrum when it came on the market, and it’s still the one to beat even after those years. Small, lightweight, powerful, and hackable, it has even spawned direct imitations.

If the TS100 has a fault, it comes not from the iron itself but from its cable. A high-grade iron will have an extra-flexible PVC or silicone cable, but the TS100 does not have a cable of its own. Instead it relies on whatever cable comes on its power supply, which is frequently a laptop unit built with portable computing rather than soldering in mind. So to use it is to be constantly battling against its noticable lack of flexibility, a minor worry but one that I find irksome. I determined to find a solution, making a DC extension cable more flexible than that on my power supply.

Unexpectedly Spawning A Product

The TS100 has a standard DC barrel jack, but surprisingly it’s rather an unusual one. It requires an extraordinarily long reach of about 15mm, and the plugs on some laptop supplies won’t mate with it satisfactorily. For my cable I would have to find the longest plug I could, and it turned out that there are surprisingly few on the market. Lumberg do one, but it tops out at too low a current rating for a soldering iron so I was rather stumped.

I approached Toby Components, my go-to supplier for connectors who have helped me secure unobtanium in the past, to see whether they had any better options. And that was where this saga took an unexpected turn. They didn’t have any off-the-shelf connectors, but they could get their cable people to make up a custom extension using an extra-flexible PVC cable. I parted with some cash, and duly received a package containing a couple of their prototypes. My build-a-cable project abruptly turned into a product test.

The first thing I did was plug it in and do some soldering, at which it was fine, and noticeably more flexible than the stock cable on my PSU. But merely saying that doesn’t give much information, I need some means of quantifying the flexibility of a cable. We can all tell by feel that one cable is more or less flexible than another. Holding it in our hands, the less flexible cable requires more force to bend it than the flexible one. Researching standard tests for cables reveals a surprise, they have a focus on safety and stress performance rather than its static physical properties, so while there are a host of fascinating tests to ensure that they don’t fail under repeated flexing or when being pinched, the standards don’t seem to include a simple measure of flexibility. It deserved some thought, so I considered and rejected measuring the droop angle of a set length of cable under its own weight, wondered whether a test rig could be set up in which a horizontal cable could have weights attached to it, and finally arrived at something much simpler.

How Do You Characterise Cable Flexibility?

My rough-and-ready minumum natural bend radius test rig.My rough-and-ready minimum natural bend radius test rig.

If you take a piece of cable and hold it between your hands, it forms a line with 180 degree angle. Should you now bend it, it won’t form a point as it takes a narrower angle, instead it will curve and tend towards a circular outline. You’ll find there is a natural minimum bend radius it will comfortably take, at which it forms the circular outline and readily returns to straightness, yet is not bent to the extent that it kinks. So measuring the natural minimum bend radius of a cable is a straightforward and easily-reproducible test that can allow comparison of cable flexibilities.

My bend radius rig is simple enough, a flat piece of wood with another slim piece of wood held above its edge using a pair of screws. The cable is bent at 180 degrees back upon itself to form a loop of its minimum natural radius, then it is clamped between the two pieces of wood, thus the diameter can be easily measured and the radius calculated. I’ve added a piece of graph paper on top of my wooden base so that I can easily judge measurements, however I found my caliper to be the most convenient way to take them. As well as the two TS100 cables I’ve measured a few others from around my bench for comparison.

Cable Diameter Radius
Toby TS100 extension cable 20mm 10mm
TS100 laptop-style PSU cable 33mm 16.5mm
“Grundlagen Audio” gold USB cable 29mm 14.5mm
Multimeter test lead 16mm 8mm
IEC computer mains lead 48mm 24mm

It can straight away be seen that this is a readily reproducible way to characterise the flexibility of a piece of cable. At the extremes are the multimeter lead and the computer mains lead, no surprise as the former is designed to be as flexible as possible while the latter is a thick and heavy mains lead. That’s a cheap multimeter, it’s likely that had I been less miserly and bought a decent one it would have a significantly more flexible set of leads. The fake “Grundlagen Audio” USB lead from my April 1st sojourn into using GNU Radio for audio analysis meanwhile is surprisingly stiff for what was in reality a cheap Amazon Basics item. This is probably due to two factors; it has a braided outer in a bid to copy more expensive leads, and my spraying it with gold paint has only made it stiffer.

To the point of the test though, the TS100 cables. The Toby cable is under two-thirds the stiffness of the laptop-style power supply cable, which does make a significant difference to the ease of soldering. I didn’t expect to spawn a product when I asked them about connector availability, but if you’d like one they have it for sale on their website. And meanwhile, Hackaday now has another test in its armoury, measuring the bend radius whenever we take a look at a cable.

Posted in cables, extension cable, Featured, soldering, tool hacks, ts100 | Leave a comment

Open Source Stream Deck Does it Without Touch Screens

[Adam Welch] has built macro pads in the past out of pre-fab key matrices and handfuls of Cherry MX clones. But all the stickers and custom keycaps in the world wouldn’t make those macro pads as versatile as a stream deck — those visual shortcut panels with tiny touchscreens for each button that some streamers use to change A/V settings or switch between applications.

Let’s face it, stream decks are expensive. But 0.96″ OLED displays are not, and neither are SMD tactile buttons. Why not imitate a screen deck on the cheap by making it so the screens actuate buttons behind them? [Adam] based this baby on the clever design of [Kilian Gosewisch]’s FreeDeck, and they ended up working together to improve it with a dedicated PCB.

The brains of the operation is an Arduino Pro Micro, which addresses each screen individually via two 74HC4051 mux ICs. Thanks to an SD card module, there’s no need to flash the ‘duino every time you want to change a shortcut or its picture. Even if this deck doesn’t hold up forever, it won’t break the bank to build another one. Poke past the break for the build video, which has all the links you’d need to make your own, including a handy configurator.

There’s more than one way to do a visual macro pad. Here’s one that uses a single screen and splits it Brady Bunch style to match the matrix.

Thanks for the tip, [arturo182]!

Posted in 74HC4051, arduino, Arduino Hacks, arduino pro micro, macro pad, oled display, sd card, stream deck | Leave a comment