Author: Dan Maloney

3359 Articles

Custom PCB Is A Poor Man’s Pick And Place

February 4, 2025 by 8 Comments

Surface mount devices have gotten really small, so small that a poorly timed sneeze can send your 0603 and 0402 parts off to live with the dust motes lurking at the edge of your bench. While soldering such parts is a challenge, it’s not always size that matters. Some parts with larger footprints can be a challenge because of the pin pitch, and getting them to land just right on the PCB pads can be a real pain.

To fight this problem, [rahmanshaber] came up with this clever custom PCB fixture. The trick is to create a jig to hold the fine-pitch parts securely while still leaving room to work. In his case, the parts are a couple of SMD ribbon cable connectors and some chips in what appear to be TQFP packages. [rahmanshaber] used FreeCAD to get the outline of each part from the 3D model of his PCB, and KiCad to design the cutouts; skip to 7:30 or so in the video below if you don’t need the design lesson. The important bit is to leave enough room around the traces so that the part’s leads can rest of the PCB while still having room to access them.

Using the fixture is pretty intuitive. The fixture is aligned over the footprint of the part and fixed in place with some tape. Solder paste is applied to the pads, the part is registered into the hole, and you’re ready for soldering. [rahmanshaber] chose to use a hot plate to do the soldering, but it looks like there’s enough room for a soldering iron, if that’s your thing.

It’s a simple idea, but sometimes the simplest tools are the best. We’ve seen lots of other simple SMD tools, from assembly jigs to solder paste stencil fixtures. Continue reading “Custom PCB Is A Poor Man’s Pick And Place” →

Homebrew Foil And Oil Caps Change Your Guitar’s Tone

February 4, 2025 by 47 Comments

How any string instrument sounds depends on hundreds of factors; even the tiniest details matter. Seemingly inconsequential things like whether the tree that the wood came from grew on the north slope or south slope of a particular valley make a difference, at least to the trained ear. Add electronics into the mix, as with electric guitars, and that’s a whole other level of choices that directly influence the sound.

To experiment with that, [Mark Gutierrez] tried rolling some home-brew capacitors for his electric guitar. The cap in question is part of the guitar’s tone circuit, which along with a potentiometer forms a variable low-pass filter. A rich folklore has developed over the years around these circuits and the best way to implement them, and there are any number of commercially available capacitors with the appropriate mojo you can use, for a price.

[Mark]’s take on the tone cap is made with two narrow strips of regular aluminum foil separated by two wider strips of tissue paper, the kind that finds its way into shirt boxes at Christmas. Each of the foil strips gets wrapped around and crimped to a wire lead before the paper is sandwiched between. The whole thing is rolled up into a loose cylinder and soaked in mineral oil, which serves as a dielectric.

To hold the oily jelly roll together, [Mark] tried both and outer skin of heat-shrink tubing with the ends sealed by hot glue, and a 3D printed cylinder. He also experimented with a wax coating to keep the oily bits contained. The video below shows the build process as well as tests of the homebrew cap against a $28 commercial equivalent. There’s a clear difference in tone compared to switching the cap out of the circuit, as well as an audible difference in tone between the two caps. We’ll leave the discussion of which sounds better to those with more qualified ears; fools rush in, after all.

Whatever you think of the sound, it’s pretty cool that you can make working capacitors so easily. Just remember to mark the outer foil lead, lest you spoil everything.

Continue reading “Homebrew Foil And Oil Caps Change Your Guitar’s Tone” →

Underwater Robotics Hack Chat

February 3, 2025 by 2 Comments

Join us on Wednesday, February 5 at noon Pacific for the Underwater Robotics Hack Chat with Tony White!

Almost anywhere you look, there’s a good chance you can see a robot at work. Whether they’re sweeping your floors, delivering a snack, building a car, or even driving one, robots are everywhere on this planet. And since over 70% of this planet is covered in water, it makes sense that robots should be there, too. Getting a robot to work underwater at all is one thing, but getting it to work underwater reliably can be quite a challenge. Water always finds a way to ruin your day, after all, and this reality only worsens when you add a little salt into the mix.

join-hack-chatTony White knows the marine engineering field well, having worked in the space for over a decade. He’s currently an applications engineer at Blue Robotics, where he’s worked on everything from full-size autonomous surface vessels to underwater swarm robots. He’s stopping by the Hack Chat to talk about the harsh engineering realities of underwater automation, so if you’ve ever wanted to take the plunge, you’ll want to come to this Hack Chat for sure.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, February 5 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

 

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Hackaday Links: February 2, 2025

February 2, 2025 by 8 Comments

All things considered, it was a very bad week for aviation here in the United States. Three separate crashes, two of which involved US military aircraft, have left over 70 people dead. We’ll spare you the details since there are plenty of other places to get news like that, but we did want to touch on one bright spot in this week’s aviation news: the first successful supersonic flight by a US-made civilian aircraft. There are a lot of caveats to that claim, but it’s clear that Boom Supersonic is on a path to commercializing supersonic air transportation for the first time since the Concorde was retired. Their XB-1 “Baby Boom” test aircraft managed three separate supersonic runs during the January 28 test flight over the Mojave test range. As usual, Scott Manley has excellent coverage of the test flight, including a look at how Boom used a Starlink terminal and an iPhone to stream cockpit video.

Continue reading “Hackaday Links: February 2, 2025” →

Custom Smartwatch Makes Diabetes Monitoring Easier For Kids

February 2, 2025 by 21 Comments

Living with Type 1 diabetes is a numbers game. There’s not a moment in the day free from the burden of tracking your blood glucose concentration, making “What’s your number?” a constant question. Technology can make that question easier to ask and answer, but for T1D patients, especially the kids who the disease so often impacts, all that tech can be a distraction.

To solve that problem for his son, [Andrew Childs] built this custom T1D smartwatch. An Apple Watch, which integrates easily into the Dexcom CGM ecosystem, seems an obvious solution, but as [Andrew] points out, strapping something like that on a nine-year-old boy’s wrist is a recipe for disaster. After toying with some prototypes and working out the considerable difficulties of getting a stable BLE connection — the device needs to connect to his son’s iPhone to get CGM data — [Andrew] started work on the physical design.

The watch uses an ESP32-S3 on a custom PCB, as well as a 1.69″ TFT IPS display and a LiPo battery. The board also has an accelerometer for activity monitoring and a vibrator for haptic feedback. Getting all that into a case was no mean feat, especially since some degree of water resistance and shockproofing would be needed for the watch to survive. [Andrew] had a case made by a local 3D printing company, and he managed to source custom-cut and silkscreened glass for the face. The result is remarkably professional-looking, especially for a software developer who hadn’t really stretched his maker wings much before tackling this project.

[Andrew] doesn’t appear to have made build files available yet, although he does say he intends to open-source the project at some point. We look forward to that as it’ll be a big help to anyone trying to hack diabetes care. Until then, if you need a primer on continuous glucose monitoring, we’re happy to oblige.

Hackaday Podcast Episode 306: Bambu Hacks, AI Strikes Back, John Deere Gets Sued, And All About Capacitors

January 31, 2025 by No comments

It was Dan and Elliot behind the microphones today for a transatlantic look at the week in hacks. There was a bucket of news about AI, kicked off by Deepseek suddenly coming into the zeitgeist and scaring the pants off investors for… reasons? No matter, we’re more interested in the tech anyway, such as a deep dive into deep space communications from a backyard antenna farm that’s carefully calibrated to give the HOA fits. We got down and dirty with capacitors, twice even, and looked at a clever way to stuff two websites into one QR code. It’s all Taylor, all the time on every channel of the FM band, which we don’t recommend you do (for multiple reasons) but it’s nice to know you can. Plus, great kinetic art project, but that tooling deserves a chef’s kiss. Finally, we wrap up with our Can’t Miss articles where Jenny roots for the right to repair, and Al gives us the finger(1).

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Continue reading “Hackaday Podcast Episode 306: Bambu Hacks, AI Strikes Back, John Deere Gets Sued, And All About Capacitors” →

Retrotechtacular: The Tyranny Of Large Numbers

January 30, 2025 by 3 Comments

Although much diminished now, the public switched telephone network was one of the largest machines ever constructed. To make good on its promise of instant communication across town or around the world, the network had to reach into every home and business, snake along poles to thousands of central offices, and hum through the ether on microwave links. In its heyday it was almost unfathomably complex, with calls potentially passing through thousands of electronic components, any of which failing could present anything from a minor annoyance to a matter of life or death.

The brief but very interesting film below deals with “The Tyranny of Large Numbers.” Produced sometime in the 1960s by Western Electric, the manufacturing arm of the Bell System, it takes a detailed look at the problems caused by scaling up systems. As an example, it focuses on the humble carbon film resistor, a component used by the millions in various pieces of telco gear. Getting the manufacturing of these simple but critical components right apparently took a lot of effort. Initially made by hand, a tedious and error-prone process briefly covered in the film, Western Electric looked for ways to scale up production significantly while simultaneously increasing quality.

While the equipment used by the Western engineers to automate the production of resistors, especially the Librascope LGP-30 computer that’s running the show, may look quaint, there’s a lot about the process that’s still used to this day. Vibratory bowl feeders for the ceramic cores, carbon deposition by hot methane, and an early version of a SCARA arm to sputter gold terminals on the core could all be used to produce precision resistors today. Even cutting the helical groove to trim the resistance is similar, although today it’s done with a laser instead of a grinding wheel. There are differences, of course; we doubt current resistor manufacturers look for leaks in the outer coating by submerging them in water and watching for bubbles, but that’s how they did it in the 60s.

The productivity results were impressive. Just replacing the silver paint used for terminal cups with sputtered gold terminals cut 16 hours of curing time out of the process. The overall throughput increased to 1,200 pieces per hour, an impressive number for such high-reliability precision components, some of which we’d wager were still in service well into the early 2000s. Most of them are likely long gone, but the shadows cast by these automated manufacturing processes stretch into our time, and probably far beyond.

Continue reading “Retrotechtacular: The Tyranny Of Large Numbers” →