hardware

1774 Articles

Using an SMD capacitor as a clip for flash media on a circuit board.

SMD Capacitor Doubles As Cheap SD Card Latch

July 4, 2025 by 41 Comments

Here’s a clever hack. Simple, elegant, and eminently cost-effective: using an SMD capacitor to hold your flash media in place!

This is a hack that can pretty much be summed up with just the image at the top of the page — a carefully placed SMD capacitor soldered to a routed tab makes for an extremely cost effective locking mechanism for the nearby SD card slot. There’s just enough flexibility to easily move the capacitor when its time to insert or eject your media.

It’s worth noting that the capacitor in this example doesn’t even appear to be electrically connected to anything. But there’s also no reason you couldn’t position one of the capacitors in your existing bill of materials (BOM). This form of mechanical support will be much cheaper than special purpose clips or mounts. Not a big deal for low-volume projects, but if you’re going high-volume this is definitely something to keep in mind.

If you’re just getting started with SMD capacitors then one of the first things to learn is how to solder them. Also, if you’re hoping to salvage them then try to look for newer equipment which is more likely to have SMD components than through-hole. If you’re planning to use your capacitors for… “capacitance” (how quaint), you can start by learning the basics. And if you want to know everything you can learn about the history of capacitors, too.

Thanks to [JohnU] for writing in to let us know about this one. Have your own natty hacks? Let us know on the tipsline!

A Crypto Miner Takes The Straight And Narrow

July 1, 2025 by 29 Comments

As it stands, cryptocurrency largely seems to be a fad of the previous decade, at least as far as technology goes. During that time, many PC users couldn’t get reasonably priced graphics cards since most of them were going into these miners. In contrast, nowadays any shortages are because they’re being used to turn the Internet into an AI-fueled wasteland. But nonetheless, there is a lot of leftover mining hardware from the previous decade and unlike the modern AI tools getting crammed into everything we own, this dated hardware is actually still useful. [Zendrael] demonstrates this by turning an old mining rig into a media server.

The mining rig is essentially nothing more than a motherboard with a large number of PCI slots, each designed for a GPU. PCI slots can do many other things, though, so [Zendrael] puts a terabyte solid state drive in each but one of the PCI cards using NVMe to PCI adapters. The final slot still hosts a GPU since the computer is being converted to a media server, and this allows it to do various encodings server-side. Even with only 4 GB of memory, the machine in its new configuration is more than capable of running Debian and spinning up all of the necessary software needed for a modern media server like Jellyfin, Nextcloud, and Transmission.

With many people abandoning miners as the value of them declines over time, it’s possible to find a lot of hardware like this that’s ready to be put to work on something new and useful. Hopefully all of the GPUs and other hardware being put to use today in AI will find a similar useful future, but until then we’ll note that you don’t need super powerful hardware to run some of those models on your own.

Continue reading “A Crypto Miner Takes The Straight And Narrow” →

Fingers installing a service loop in a wire in a connector

Are Service Loops A Good Idea?

July 1, 2025 by 23 Comments

Well, here’s an interesting idea: the service loop. Ever heard of it? We haven’t!

In the video, the presenter explains the service loop serves two purposes: on the one hand it may provide strain relief, but chiefly these loops are installed so there will be extra available slack in the cable if you need to rewire it some day to change the configuration of your pinout.

One major problem with the service loop may be that the single turn is enough to create an inductor which will then induce noise and cross-talk all over the place. Our rule of thumb is always to completely unroll wires and cables before using them. Do you have a theory about the benefits or problems with service loops? If you do, we’d love to hear what you think in the comments!

If you’re interested in strain relief, we’ve covered that before, and you don’t need a service loop to do it! Check out Cheap Strain Relief By Casting Hot Glue In A 3D Print and Arduino Uno Strain Relief.

Continue reading “Are Service Loops A Good Idea?” →

A Cheap Smart Plug To Block Distractions

June 27, 2025 by 19 Comments

We have all suffered from this; the boss wants you to compile a report on the number of paper clips and you’re crawling up the wall with boredom, so naturally your mind strays to other things. You check social media, or maybe the news, and before you know it a while has been wasted. [Neil Chen] came up with a solution, to configure a cheap smart plug with a script to block his diversions of choice.

The idea is simple enough, the plug is in an outlet that requires getting up and walking a distance to access, so to flip that switch you’ve really got to want to do it. Behind it lives a Python script that can be found in a Git Hub repository, and that’s it! We like it for its simplicity and ingenuity, though we’d implore any of you to avoid using it to block Hackaday. Some sites are simply too important to avoid!

Of course, if distraction at work is your problem, perhaps you should simply run something without it.

Animal Crossing keyboard banner

Making GameCube Keyboard Controller Work With Animal Crossing

June 26, 2025 by 2 Comments

[Hunter Irving] is a talented hacker with a wicked sense of humor, and he has written in to let us know about his latest project which is to make a GameCube keyboard controller work with Animal Crossing.

This project began simply enough but got very complicated in short order. Initially the goal was to get the GameCube keyboard controller integrated with the game Animal Crossing. The GameCube keyboard controller is a genuine part manufactured and sold by Nintendo but the game Animal Crossing isn’t compatible with this controller. Rather, Animal Crossing has an on-screen keyboard which players can use with a standard controller. [Hunter] found this frustrating to use so he created an adapter which would intercept the keyboard controller protocol and replace it with equivalent “keypresses” from an emulated standard controller.

Continue reading “Making GameCube Keyboard Controller Work With Animal Crossing” →

IOT 7-segment display

Modern Tech Meets Retro 7-Segment

June 23, 2025 by 7 Comments

At one point in time mechanical seven segment displays were ubiquitous, over time many places have replaced them with other types of displays. [Sebastian] has a soft spot for these old mechanically actuated displays and has built an open-source 7-segment display with some very nice features.

We’ve seen a good number of DIY 7-segment displays on this site before, the way [Sebastian] went about it resulted in a beautiful well thought out result. The case is 3D printed, and although there are two colors used it doesn’t require a multicolor 3d printer to make your own. The real magic in this build revolves around the custom PCB he designed. Instead of using a separate electromagnets to move each flap, the PCB has coil traces used to toggle the flaps. The smart placement of a few small screws allows the small magnets in each flap to hold the flap in that position even when the coils are off, greatly cutting down the power needed for this display. He also used a modular design where one block has the ESP32 and RTC, but for the additional blocks those components can remain unpopulated.

The work he put into this project didn’t stop at the hardware, the software also has a great number of thoughtful features. The ESP32 running the display hosts a website which allows you to configure some of the many features: the real-time clock, MQTT support, timer, custom API functions, firmware updates. The end result is a highly customizable, display that sounds awesome every time it updates. Be sure to check out the video below as well as his site to see this awesome display in action. Also check out some of the other 7-segment displays we’ve featured before.

Continue reading “Modern Tech Meets Retro 7-Segment” →

A green box with the answer to if a nuke has gone off with red neon lights

Has A Nuke Gone Off? Indicator

June 22, 2025 by 23 Comments

Look out of a window, ask yourself the question, “Has a nuke gone off?”. Maybe, maybe not, and all of us here at Hackaday need to know the answer to these important questions! Introducing the hasanukegoneoff.com Indicator from [bigcrimping] to answer our cries.

An ESP32 running a MicroPython script handles the critical checks from hasanukegoneoff.com for any notification of nuclear mayhem. This will either power the INS-1 neon bulb, indicating “no” or “yes” in the unfortunate case of a blast. Of course, there is also the button required for testing the notification lights; no chance of failure can be left. All of this is fitted onto a custom dual-sided PCB and placed inside a custom 3D-printed enclosure.

Hasanukegoneoff.com’s detection system, covered before here, relies on an HSN-1000L Nuclear Event Detector to check for neutrons coming from the blast zone. [bigcrimping] also provides the project plans for your own blast detector to answer the critical question of “has a nuke gone off” from anywhere other than the website’s Chippenham, England location.

This entire project is open sourced, so keep sure to check out [bigcrimping]’s GitHub for both portions of this project on the detector and receiver. While this project provides some needed dark humor, nukes are still scary and especially so when disarming them with nothing but a hacksaw and testing equipment.

Thanks to [Daniel Gooch] for the tip.