The Bendix G-15 refurbished by [David at Usagi Electric] is well known as the oldest fully operational digital computer in North America. The question [David] gets most is “what can you do with it?”.  Well, as a general-purpose computer, it can do just about anything. He set out to prove it. Can a 1950s-era vacuum tube computer handle modern physics problems? This video was several years in the making, was a journey from [David’s] home base in Texas all the way to CERN’s Large Hadron Collider (LHC) in Switzerland.

The G-15 can run several “high-level” programming languages, including Algol.  The most popular, though, was Intercom. Intercom is an interactive programming language – you can type your program in right at the typewriter. It’s much closer to working with a basic interpreter than, say, a batch-processed IBM 1401 with punched cards. We’re still talking about the 1950s, though, so the language mechanics are quite a bit different from what we’re used to today.

To start with, [Usagi’s] the G-15 is a numeric machine. It can’t even handle the full alphabet. What’s more, all numbers on the G-15 are stored as floating-point values. Commands are sent via operation codes.  For example, ADD is operation 43.  You have to wrangle an index register and an address as well.  Intercom feels a bit like a cross between assembler and tokenized BASIC.

If you’d like to play along, the intercom manual is available on Bitsavers. (Thanks [Al]!)

In the second half of the video, things take a modern turn. [David’s] friend [Lloyd] recently wrote a high-speed algorithm for the ATLAS detector running at the Large Hadron Collider at CERN.  [Lloyd] was instrumental in getting the G-15 up and running.  Imagine a career stretching from the early days of computing to modern high-speed data processing. Suffice to say, [Lloyd] is a legend.

There are some hardcore physics and high speed data collection involved in ATLAS. [Allison] from SMU does a great job of explaining it all. The short version is:  When particles are smashed together, huge amounts of information is collected by detectors and calorimeters. On the order of 145 TB/s (yes, terabytes per second). It would be impossible to store and analyze all that data. Topoclustering is an algorithm that determines if any given event is important to the researchers or not. The algorithm has to run in less than 1 microsecond, which is why it’s highly pipelined and lives inside an FPGA.

Even though it’s written in Verilog, topoclustering is still an algorithm. This means the G-15, being a general-purpose computer, can run it. To that end, [Lloyd] converted the Verilog code to C. But the Bendix doesn’t run C code. That’s where  G-15 historian [Rob Kolstad] came in. Rob ported the C code to Intercom. [David] punched the program and a sample dataset on a short tape.  He loaded up Intercom, then Topoclustering, and sent the run command.  The G-15 sprang to life and performed flawlessly, proving that it is a general-purpose computer capable of running modern algorithms.

Curious about the history of this particular Bendix G-15? Check out some of our earlier articles!

It’s been 30 years since Windows 95 launched. [Ms-Dos5] and [Commodore Z] are celebrating with an epic exhibit at Vintage Computer Festival East 2025. They had no fewer than nine computers — all period-correct machines running versions of Windows 95. The pictures don’t do it justice, so if you are near Wall, NJ, on Sunday, April 5, 2025, definitely go check out this and the rest of the exhibits at VCF.

An exhibit like this isn’t thrown together overnight.  [Commodore Z] and [Ms-Dos5] worked for months to assemble the right mix of desktops, laptops, and peripherals to showcase Windows 95. Many of the computers are networked as well – which was no easy task.

One particular Thinkpad 760e required pliers and force to remove a stuck PCMCIA modem card. After a struggle that was ultimately destructive to the card, the pair determined it was stuck due to a sticker that had effectively glued the card into the laptop. As the sticker finally gave up, the card popped itself out of the laptop.

Hardware isn’t the only story of this Windows 95 exhibit. An operating system is software, after all. The team has plenty of software running. Some highlights are Kid Pix, MS-paint, LEGO Island, Full Throttle, Duke Nukem 3D, Word 97, and Space Cadet Pinball, which came with the Plus! expansion pack. There is a huge array of original boxes for Windows 95 software. It’s a nostalgia trip to see software in boxes, especially in all those bright 90’s colors.

The various versions of Windows 95 are also represented. [Ms-Dos5] and [Commodore Z] are running all major versions from Chicago beta 73g to Windows 95 C / OSR2.5.

If you’re old enough to remember it, the Windows 95 launch event was a big deal. Windows 3.0 series was five years old at that point. Millions of people owned PC compatible computers and were ready for something new and flashy, and Windows 95 delivered. Thanks to [Commodore Z] and [Ms-Dos5] keeping this bit of internet history alive.

[Abe] wanted the perfect portable computer. He has a DevTerm, but it didn’t quite fit his needs. This is Hackaday after all, so he loaded up his favorite CAD software and started designing. The obvious choice here would be a Raspberry Pi. But [Abe] didn’t want to drop in a Linux computer — he was going for something a bit smaller.

An RP2040 Pico would be a perfect fit. Driving a display with the Pico can be eat a lot of resources though. The solution was a PicoVision from Pimoroni. PicoVision uses two RP2040 chips. One drives an HDMI port, while the other is free to run application software. This meant a standard HDMI screen could be used.

The keyboard was a bit harder. After a lot of searching, [Abe] found an IR remote designed for smart TVs. The QWERTY keyboard was the perfect size but didn’t have an interface he could use. He fixed that with an adapter PCB including an I2C GPIO expander chip. A bit of I2C driver software later, and he had a working input keyboard.

Hardware doesn’t do anything without software though. The software running on the handheld is called Slime OS, and the source is available at [Abe’s] GitHub. It’s a launcher, with support for applications written in python. [Abe] has a few basic demos working, but he’s looking for help to get more features up and running.

Although it wasn’t quite what [Abe] was after, our own [Donald Papp] came away fairly impressed when he gave the DevTerm a test drive back in 2022. Something to consider if you’re looking for a Linux handheld and not quite ready to build one yourself.

Just when you think you’ve learned all the latest 3D printing tricks, [TenTech] shows up with an update to their Fuzzyficator post-processing script. This time, the GPL v3 licensed program has gained early support for “paint-on” textures.

Fuzzyficator works as a plugin to OrcaSlicer, Bambu Studio, and PrusaSlicer. The process starts with an image that acts as a displacement map. Displacement map pixel colors represent how much each point on the print surface will be moved from its original position. Load the displacement map into Fuzzyficator, and you can paint the pattern on the surface right in the slicer.

This is just a proof of concept though, as [TenTech] is quick to point out. There are still some bugs to be worked out. Since the modifications are made to the G-code file rather than the model, the software has a hard time figuring out if the pattern should be pressed into the print, or lifted above the base surface. Rounded surfaces can cause the pattern to deform to fit the surface.

If you’d like to take the process into your own hands, we’ve previously shown how Blender can be used to add textures to your 3D prints.

We all take Ethernet and its ubiquitous RJ-45 connector for granted these days. But Ethernet didn’t start with twisted pair cable. [Mark] and [Ben] at The Serial Port YouTube channel are taking a deep dive into the twisted history of Ethernet on twisted pair wiring. The earliest forms of Ethernet used RG-8 style coaxial cable. It’s a thick, stiff cable requiring special vampire taps and lots of expensive equipment to operate.

The industry added BNC connectors and RG-58 coax for “cheapernet” or 10Base2. This reduced cost, but still had some issues. Anyone who worked in an office wired with 10Base2 can attest to the network drops whenever a cable was kicked out or a terminator was dropped.

The spark came when [Tim Rock] of AT&T realized that the telephone cables already installed in offices around the world could be used for network traffic. [Tim] and a team of engineers from five different companies pitched their idea to the IEEE 802.3 committee on Feb 14, 1984.

The idea wasn’t popular though — Companies like 3COM, and Digital Equipment Corporation had issues with the network topology and the wiring itself. It took ten years of work and a Herculean effort by IEEE committee chairwoman [Pat Thaler] to create the standard the world eventually came to know as 10Base-T. These days we’re running 10 Gigabit Ethernet over those same connectors.

For those who don’t know, this video is part of a much larger series about Ethernet, covering both history and practical applications. We also covered the 40th anniversary of Ethernet in 2020.

If you’re into building large projects, you’ll eventually find yourself looking at wire rope. Multistrand steel wire used as antenna guy wires, bridge supports, and plenty of other uses.  The [HowNot2] team tested an old rule of thumb for wire rope. “Never saddle a dead horse”.

Click through the break for more:

The old saying refers to the clips used on wire rope. These clips have a saddle, and u shaped bolt. As the diagram shows, the saddle side of the bolt should always go on the live (loaded) end of the cable, not the dead (cut) end.  This is because the saddle has teeth to grip the cable, and protects it from crimping and damage over time.

[HowNot2] tests a number of different wire rope clamps – including improper installation.  The best clamps are hydraulically crimped connectors. These require some expensive tooling — which is worth it when your life depends on the connection.

When testing got to the u-clips, saddling the live side went fine. When saddling the “dead horse”, the pull test failed at a lower force. Before the failure though, the joint made sounds that would instill fear in the heart of anyone who’s been around heavy equipment or cranes. The adage turns out to be true – never saddle a dead horse.

If you really want to know more about wire rope rigging, the US Navy has you covered.

[Mattmopar] figured out how to get a white Christmas even if the weather isn’t frightful. He built a simple DIY snow making machine with a few plumbing parts, and tools you probably already have. Snowmaking machines used on the ski slopes cost tens of thousands of dollars. Even the “low-cost” home versions are $400 and up.

[Matt] cut things down to the basics.  Snowmaking requires two ingredients: Water and compressed air.  The water is coming from a cheap electric pressure washer he found used.  The air pressure is from an old air compressor. [Matt] is using his shop compressor – but even a cheap compressor will do fine.

The cold is an unforgiving environment though – so a few changes are needed. The trick is to use garden hose instead of air hose. Traditional air hose has a rather small hole. This leads to ice clogs coming from the compressor itself.  A check valve also ensures that water from the pressure washer doesn’t back up into the compressor.

The nozzles are pressure washer nozzles.  Two 40 degree nozzles for the water, and a 65 degree nozzle for the air/water mix. In true hacker style, the frame of the machine is a ladder, and the gun attached via zip-ties.

Of course you still need cold temperatures for this to work, but that’s not too hard in the winter months. Now if you have the opposite problem of too much snow, check out this self clearing concrete.