FPGA Powers DIY USB Scope And Signal Generator

Oscilloscopes and to lesser extent signals generators are useful tools for analyzing, testing and diagnosing circuits but we often take for granted how they work. Luckily, [FromConceptToCircuit] is here to show us how they’re made.

[FromConceptToCircuit] starts by selecting the hardware to use: an Artix-7-based FPGA and an FT2232 USB-serial converter. RS245 in synchronous FIFO mode is selected for its high bandwidth of about 400 Mbps. Then, they show how to wire it all up to your FPGA of choice. Now it’s time for the implementation; they go over how the FT2232 interfaces with the FPGA, going through the Verilog code step-by-step to show how the FPGA makes use of the link, building up from the basic transmission logic all the way up to a simple framed protocol with CRC8-based error detection. With all that, the FPGA can now send captured samples to the PC over USB.

Now it’s PC-side time! [FromConceptToCircuit] first explains the physical pipeline through which the samples reach the PC: FPGA captures, transmits over RS245, FT2232 interfaces that with USB and finally, the software talks with the FT2232 over USB to get the data back out. The software starts by configuring the FT2232 into RS245 mode, sets buffer sizes, the whole deal. With everything set up, [FromConceptToCircuit] explains how to use the FT2232 driver’s API for non-blocking communication.

As a bonus, [FromConceptToCircuit] adds a signal generator feature to the oscilloscope using an I2C DAC chip. They start by explaining what exactly the DAC does and follow up with how it’ll be integrated into the existing system. Then it’s time to explain how to implement the I2C protocol bit-for-bit. Finally combine everything together for one final demo that shows a sine wave on the DAC’s output.

Desktop Digitizer Makes Note Capture A Breeze

While it might seem quaint these days, we’ve met many makers and hackers who reach for a pen and a pad when learning something new or working their way through some technical problem. But even if you’re the type of person who thinks best when writing something out on paper, there’s still a good chance that you’ll eventually want to bring those notes and sketches into the digital realm. That’s where things can get a little tricky.

[Spencer Adams-Rand] recently wrote in with his clever solution for capturing written notes and pushing them into Notion, but the hardware design and digitization workflow is flexible enough that it could be adapted to your specific needs — especially since he was good enough to release all the files required to build your own version.

Whether they are hand-written notes, old photographs, or legal documents, digitization boils down to taking a high resolution digital photo of the object and running it through the appropriate software. But getting good and consistent photos is the key, especially when you’re working your way through a lot of pages. [Spencer] started out just snapping pictures with his phone, but quickly found the process was less than ideal.

His custom scanning station addresses that first part of the problem: getting consistent shots. The images are captured using a Raspberry Pi 5 with attached Camera Module 3, while the 3D printed structure of the device makes sure that the camera and integrated lighting system are always in the same position. All he needs to do is place his notepad inside the cavity, hit the button, and it produces a perfect shot of the page.

Using a dedicated digitizing station like this would already provide better results than trying to freehand it with your phone or camera, but [Spencer] took things quite a bit farther. The software side of the project puts a handy user interface on the 5 inch touch screen built into the top of the scanner, while also providing niceties like a REST API and integration with the OpenAI Vision API for optical character recognition (OCR).

Those with an aversion to AI could certainly swap this out for something open source like Tesseract, but [Spencer] notes that not only is OpenAI’s OCR better at reading his handwriting, it spits out structured markdown-like data that’s easier to parse. From there it goes into the Notion API, but again, this could be replaced with whatever you use to collect your digital thoughts.

A device like this would go a long way towards answering a question we posed to the community back in January about the best way to digitize your documents.

The Kentucky Cave Wars, And Going Viral In 1925

Floyd Collins, the unfortunate star of this post. (Public Domain)

Information, it seems, flows at the speed of media. In the old days, information traveled with people on ships or horses, so if, say, a battle was won or lost, it could be months or even years before anyone back home knew what happened. While books and movable type let people store information, they still moved at the speed people moved. Before the telegraph, there were attempts to use things like semaphores to speed the flow of information,  but those were generally limited to line-of-sight operations. Carrier pigeons were handy, but don’t really move much faster than people.

The telegraph helped, but people didn’t have telegraph stations in their homes. At least not ordinary people. But radio was different. It didn’t take long for every home to have a radio, and while the means of broadcasting remained in the hands of a few, the message could go everywhere virtually instantly. This meant news could go from one side of the globe to the other in seconds. It also meant rumors, fads, and what we might think of today as memes could, too.

You might think that things “going viral” is a modern problem, but, in reality, media sensations have always been with us. All that changes is the number of them and their speed.

One of the earliest viral media sensations dealt with William Floyd Collins, an unfortunate man who was exploring caves during the Kentucky Cave Wars.

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Emergency Bolt-Action Launcher For EpiPens

Imagine you and your friend are enjoying a nice sunny day, and BAM — they start to have a severe allergic reaction to who knows what. You have an EpiPen, but your friend is on the other side of a field! The solution? Obviously [Emily The Engineer] has only one option: build an entire EpiPen launcher!

Starting off the life-saving project, [Emily] prototyped with a 3D printed blank and a simple solenoid-controlled glorified potato cannon. This proved effective, as one would expect of such a project after successful tests on a human subject. However, there was one simple problem: what if you missed your initial shot?

To ensure no possible failed missions, a bolt-action magazine was retrofitted onto the device. Additionally, an air compressor placed in a mobile backpack carrier allows for repeated mobile use. Official testing was done on ballistic gel before a “war game” scenario played out involving an anaphylactic friend. As one would assume, this went perfectly, ignoring the time delay of having to wait for the compressor to build up enough pressure…

Anyways, even if you won’t be using this EpiPen launcher anytime soon, there are some actual DIY medical miracles you can look into! Something that’s a tad less insane to hack together than an EpiPen gun would be a splint. That is exactly what you can learn about here!

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Trying To Build Your Own Consumer-Grade Router In 2026

Although we have many types of networking equipment with many unique names, at their core they can usually be reduced to just a computer with some specific peripherals. This is especially the case for something like a router, a device found in just about any home these days. Certain consumer-grade routers may contain something special like a VDSL modem, but most of them just have a WAN Ethernet jack on one end and one or more LAN-facing Ethernet ports.

All further functionality is implemented in software, including any firewall, routing and DHCP features. What this means is that any old PC with at least two Ethernet ports or equivalent can be a router as long as you install the appropriate software.

In this article we’ll be taking a look at what consumer-level options there exist here today, ideally something so simple that the average home user could set it up with a bit of coaching.

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A Raspberry Pi Zero-based camera in a nice yellow case. There's a yellow lanyard, too.

Optocam Zero’s Pictures Look One Hundred

Yeah, we know, there’s a camera on your phone that does this and that. But these days its become trendy to turn towards older digital cameras in place of smartphones, and we can tell you from experience, that the joys of having a dedicated photographing contraption are many.

There’s plenty of cheap digital cameras on the secondhand market, but instead of fending off the clothes bros and other reseller types at the thrift store, stay home and build [Doruk Kumkumoğlu]’s Optocam Zero. Inspired by the Kodak Charmera and the like, [Doruk] aimed for something that’s playful, enjoyable, and intuitive to use.

Optocam Zero uses an auto-focus camera module and features eight photo filters. The screen dims when inactive to preserve battery life, but it can be charged back up with USB-C, and you can use it for the duration. And unlike my young adult camera, you don’t have to take out the SD card to see the pictures, just use the custom hotspot interface to transfer them.

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Robot Bird Decoys Work For Good

Usually, you think of bird decoys as being a tool to lure birds to an untimely encounter with a hunter. However, [Interesting Engineering] has a story about robotic bird decoys in Grand Teton National Park that are helping restore the dwindling number of sage grouse in the park.

While some decoys are static, others are motorized to replicate mating rituals. The goal: lure real birds to safer areas to breed. Particularly, they want the birds to avoid areas around the Jackson Hole Airport. The robots are built with help from local students and robotics teams. While some of the construction is made of fabric and foam, actual bird feathers are also used.

The robots mimic lekking behavior, a courtship ritual where male grouse do repetitive motions combined with recorded mating calls. This attracts other grouse and, of course, results in chicks who will be raised nearby.

Assuming the effort is successful, the same technique could help other areas where restored areas are difficult to repopulate. You can find more pictures on the Park’s Instagram, and the title picture is from that collection.

Usually, when we see something like this, the robot is trying to remove something dangerous to the endangered plant or animal, not attract them.