Author: Al Williams

4351 Articles

Handheld PC Looks Great

May 22, 2023 by 13 Comments

[Bytewelder] fondly remembers the Palm III and Sharp HC-4500, so taking on the design of Decktility, a custom handheld cyberdeck , was a natural next step. The blog post goes into much detail about the design decisions and challenges throughout the project. The end result, though, looks great.

The device uses a Raspberry Pi CM4 and an IPS touchscreen. The bulk of the design work was to get the power system working. There is a custom FET board and an Arduino that manages charging and battery state.

Continue reading “Handheld PC Looks Great” →

ChatGPT Rules The World… Or, At Least, The Home

May 22, 2023 by 17 Comments

With all the hype about ChatGPT, it has to have crossed your mind: how can I make it control devices? On the utopia side, you could say, “Hey, ChatGPT, figure out what hours I’m usually home and set the thermostat higher when I am away.” On the dysfunctional side, the AI could lock you in your home and torment you like some horror movie. We aren’t to either extreme yet, but [Chris] couldn’t resist writing a ChatGPT plugin to control a Raspberry Pi. You can see a video of how it turned out below.

According to [Chris], writing a ChatGPT plugin is actually much simpler than you think. You can see in the video the AI can intuit what lights to turn on and off based on your activity, and, of course, many more things are possible. It can even detect snoring.

Continue reading “ChatGPT Rules The World… Or, At Least, The Home” →

The Wizard Of Semiconductors

May 22, 2023 by 19 Comments

If you have three hours and you want to learn the fundamentals of semiconductors, [Tiny Tapeout] has something for you: An introduction to SiliWiz. You’ll also need the SiliWiz software (or use it online), which resembles the kind of tools that chip designers use but is meant for students to use as a learning tool

Using SiliWiz, you create layers on a virtual device, and you can use Spice to view the results. The tutorial is meant to be high-level and is suggested for students aged 14 or over (but we liked it and we are quite a bit older than that). Some more advanced material is also available at the same site.

Continue reading “The Wizard Of Semiconductors” →

A Look Back At Computer Displays

May 21, 2023 by 10 Comments

These days, our video cards are actually as powerful as yesterday’s supercomputer and our monitors are bigger than the TVs most of us had as kids. But how did we get there? [RetroBytes] covers computer displays starting with the Colossus computer to today.

Back in the days of Colossus, of course, a display was actually a TeleType-like device printing on a roll of paper. The Manchester Baby actually had a crude display which was actually a Williams tube (no relation) that used phosphor persistence to store data. You could physically see memory on the tube or monitor it on a parallel tube — an early form of memory-mapped display.

Continue reading “A Look Back At Computer Displays” →

Easy Graphene Production With A Laser Engraver

May 20, 2023 by 14 Comments

Graphene isn’t easy to produce at scale. But making small batches of graphene is doable in a few ways. [Robert Murray-Smith] decided to try producing “flash graphene.” This requires a big capacitor bank that is moderately expensive, so he decided to explain a different technique he read about using an ordinary laser cutter. Check it out in the video below.

We were a little disappointed that he didn’t actually make any graphene this time. He has, however, used other methods in other videos to create some type of graphene. In fact, he has many similar videos going back quite a ways as well as applications with concrete, capacitors, and more. We understand that this method doesn’t produce monolayer graphene, but actually creates a graphene “foam” with interesting properties. [Robert] talks about recent papers that show you can grow graphene on things other than Kapton tape using this method.

Continue reading “Easy Graphene Production With A Laser Engraver” →

Hexed Home Assistant Monitors 3D Printers

May 20, 2023 by 6 Comments

You can babysit your 3D printer 100% of the time, or you can cross your fingers and hope it all works. Some monitor their printers using webcams, but [Simit] has a more stylish method of keeping tabs on six 3D printers.

The idea is to use a 3D printed hex LED display found online. Adding an ESP32 and Home Assistant allows remote control of the display. The printers use Klipper and can report their status using an API called Moonraker. Each hexagon shows the status of one printer. You can tell if the printer is online, paused, printing, or in other states based on the color and amount of LEDs lit. For example, a hex turns totally green when printing is complete.

Once you have a web API and some network-controlled LEDs, it is relatively straightforward to link it together with Home Automation. Of course, you could do it other ways, too, but if you already have Home Automation running for other reasons, why not?

We have seen other ways to do this, of course. If you need an easy monitor, the eyes have it. If you don’t use Klipper, OctoPrint can pull a similar stunt.

3D Printing Blueprints And Other Wall Art

May 19, 2023 by 3 Comments

Today if you want to reproduce a big schematic or a mechanical drawing, you just ask it to print or plot from the CAD model. But back in the day, you drew on big sheets at a drafting table. How do you make copies? Sure, there were a few large-format copiers, but they were expensive. A more common method was to use a heliographic copier which, often but not always, resulted in a blueprint — that is a blue page with white lines or vice versa. These days, you are more likely to see a blueprint as an artistic wall hanging, and since [Basement Creations] wanted some, he figured out how to make them with a 3D printer.

These prints aren’t really blueprints. They use the printer as a plotter and deposit white ink on a blue page. In the video below, he shows a number of ways to use a printer to create interesting wall art, even if you want it to be bigger than the print bed. Some of the wall art uses multiple 3D printed parts, and others use the printer as a plotter.

Continue reading “3D Printing Blueprints And Other Wall Art” →