The Seven Sensors And Breakout Boards To Avoid In A Product

August 2, 2026 by Maya Posch 56 Comments

We’ve all seen these sensors and modules kicking around, as part of beginner kits, strapped into prototypes and potentially even in products deployed in the field. Yet as [John Teel] rightfully points out in a recent video, most of these have no business ever being used in a real product, and might not even be suitable for prototyping.

First up is a combination of the related DHT11 and DHT22 temperature-humidity sensors. As common as these are, they’re also pretty sketchy with their proprietary one-wire protocol and at most questionable accuracy, worsened by not having a good supply chain. The replacements are plentiful: the SHT40 and SHT41, the Bosch Sensortec BME280 or BMP180, as well as TI’s HDC3020. These get you standard I2C communication and a supply chain plus a datasheet you can trust.

Second is the HC-SR04 ultrasonic distance sensor. Although fine for prototyping, it’s a 5 V module, lacks temperature compensation and other features that’d be needed outside a temperature-controlled room. Here ST’s VL53 Time-of-Flight sensors are a good alternative, containing a range of sensors of which we covered the fancier VL53L5CX previously for 3D scanning a room. Of course, you can also use reflective IR as a good cheap alternative.

Third is the HC-SR501 passive infrared (PIR) motion module. This one is also fine for PIR and motion sensing prototyping, but is too inconsistent and power-hungry for production. Instead you can get much better and much smaller PIR modules, like the Panasonic EKMC and EKMB, or the ST STHS34 IR motion and presence sensor.

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Testing A 3D Printed Cycloidal Gearbox Design

August 1, 2026 by Maya Posch 3 Comments

Cycloidal gearboxes are a recurring theme in the hobbyist space due to the performance they promise in a compact package. They are capable of taking in a high-speed input and reducing it down to a set ratio with very low backlash, which theoretically makes them perfect for a wide range of projects where size and weight matter. Correspondingly, [Advanced Hobby Lab] has been tinkering with a 3D printed design to fit on NEMA 17 stepper motors.

For [Advanced Hobby Lab] the primary goal was to check that his cycloidal gearbox design was a real improvement over the planetary gearbox alternative. Although the 3D printed cycloidal drive worked well enough, some testing put real numbers to it, including a 92% efficiency. The gearbox also adds some noise over the stepper motor, but less so than the 3D printed planetary gearbox.

Of course, all of this is within the limits of FDM 3D printing and with a few metal parts, so there’s always room for improvement, but in the world of hobbyist 3D printed gearboxes it’s not a bad showing. The print and project files are available for anyone who is also feeling the itch. Of course, you can also opt for the dual-nested cycloidal design that we recently featured, as it promises to be even more compact, have even fewer parts and smoother action.

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Casual Repair And Maintenance On An Amiga 1000

July 31, 2026 by Maya Posch 16 Comments

Recently [Drygol] had an Amiga 1000 system over for some repairs as well as maintenance and general TLC. This is a Motorola 68000-based home computer from 1985 that also has the distinction of being the first Amiga system to be released by Commodore. At a time when the IBM PC was still strutting its monochrome and EGA graphics alongside PC speaker beeps, the Amiga 1000 featured relatively high-res graphics and advanced stereo audio courtesy of special accelerator chips.

Overall the system was in a pretty good condition, even coming with the very nifty modern Parceiro expansion that adds 8 MB of fast RAM, an SD card slot and RTC. This thus meant that they mostly just had to perform the typical maintenance task, such as recapping the PSU and mainboard, as well as recapping and lubing up the floppy drive. The original 230 VAC fan in the PSU also got swapped with a 12V unit that was much quieter.

After disassembling the keyboard for some deep cleaning and retr0brighting, a little glitch in the form of the use of a too long screw by a previous owner was addressed, as well as a broken plastic clip. With how little attention the Amiga 1000 received after its release it’s good to see some of these units still kicking.

Turning Glass Into A Touch-Sensitive Button

July 31, 2026 by Maya Posch 4 Comments

Although generally glass isn’t associated with touch-sensitive surfaces, the addition of an ITO (indium tin oxygen) coating adds the exciting property of not only being transparent to the visible light part of the electromagnetic spectrum, but also of being electrically conductive. The logical result is that fine folk like [Sokol] simply had to use their newly acquired ITO-coated glass to make a button out of.

Here the easy option is of course to just use it as a capacitive sensor where the conductive ITO layer is used for the capacitive charge and the glass provides the insulator, but here we see it demonstrated how to create a pressure-sensitive implementation instead.

The measured conductivity on the ITO-coated glass in the video is pretty good, at just over 20 Ohm. This thus makes said capacitive button very easy to achieve. To make it a touch-sensitive button, two pieces of glass are used, with the ITO sides facing. Paper is used to create a spacer, after which the slight flex of the glass allows for the two ITO surfaces to touch, completing the circuit.

This is somewhat similar to how resistive touch screens work, with the position of the finger or stylus determined by the resistance between the two sides. In a hobbyist setup this would make it fairly easy to create a multi-position touch screen using just two pieces of glass and some firmware.

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Using The Chimney Effect To Drop Passively Cooled PC Temperatures

July 31, 2026 by Maya Posch 33 Comments

The stack effect — also known as the chimney effect — is the basic principle that hot air not only rises, but if guided through a tube, the rising hot air will create more pressure that will effectively draw air more effectively into the tube. This is not only great for a chimney, but also a useful principle if you seek to cool something like a PC in a more passive manner. The main question is of course how much of a ‘chimney’ you need to see real effects for something like a typical water-cooled CPU’s radiator, as demonstrated by [der8auer] in a recent video.

Although there’s a lot of fun physics behind the stack effect that you can run the numbers on, the more practical demonstration here using 3D printed funnel segments for the radiator and various thermometers provides a very hands-on feeling for what you can expect from this approach.

With just a single segment stacked there is already a clearly noticeable temperature change, with the second segment creating a draft as visualized by the smoke machine. After this he goes for broke with the full stack and a resulting 19°C temperature drop on the CPU. While impressive, at this point the required funnel gets a bit silly, though the same principle has been applied to computer cases before, including the passively-cooled Power Mac G4 Cube and the 90-degrees-rotated SilverStone Raven series of cases, like the RV02.

The basic idea of making use of the fact that hot air rises, and maybe also banking on the stack effect for some free passive cooling, clearly isn’t so crazy.

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Fixing A JMicron-Based M.2 USB Enclosure That Stopped Working

July 30, 2026 by Maya Posch 10 Comments

As useful as USB-to-M.2 SSD adapters are, sometimes you come across a bit of a dud. A case in point is the Orico-branded TCM2-C3 that features both an attractive clear case and in its earlier revisions a JMicron controller-based circuit that apparently degrades over time, causing erratic boot behavior. After implementing a fix a few years ago, [Mark Furneaux] can happily report that the thus fixed enclosures are still working.

These faulty board revisions feature the JMicron JMS583 controller IC, which has a 1.0V core voltage input pin. Apparently to save power, Orico designed the board to target the minimum ~0.95V core voltage per the datasheet. Apparently due to component drift or degradation, this lower core voltage is after a while often not enough any more to start the controller, which thus translates into an unresponsive USB device and presumably some panic about lost data.

Although [Mark] doesn’t describe the fix in detail, it entails bumping up this core voltage to something closer to the nominal 1.0V, which restores functionality at the cost of presumably a measurable amount of extra heat production by said controller.

Later versions of the Orico TCM2-C3 enclosure switched from this JMicron controller to a Realtek one, which so far appears to be noticeably more reliable. Although Orico kept the same model name, the transparent enclosure makes it at least a snap to see which revision you are dealing with.

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DOOM Using Regular Expressions

July 28, 2026 by Maya Posch 16 Comments

Regular expressions (regexes) are an amazingly powerful way to perform operations on collections of e.g. text. Regexss can also be considered to be a programming language, even a Turing complete one. Ergo it’s perfectly acceptable to thus design a way to use regexes to run and play a game of DOOM, as [Artem Lytkin] recently did.

The GitHub project page can be found here, containing the Python-based code that allows the demonstration to run, as well as the other components, including the C runtime and the 96.6 MB text string that defines a CPU’s registers, RAM, a framebuffer, the DOOM engine compiled to this custom CPU’s instruction set and the WAD file for the game itself.

The C-based driver applies the fixed, ordered list of find-and-replace rules to this string, which after more than ten-thousand of such substitutions later results in a single frame of the game. At about 80,000 substitutions per second on the given test system, that gets you to a sort-of playable framerate, even.

Naturally, the practical value of playing DOOM like this is pretty low, but as a demonstration of why regexes are awesome it’s hard to beat.