Putting this out there for search engines, since someone will probably need it some day. Symptom: Dell Chromebook 11 inch 3380 would not turn on, despite being on charger all night. Same effect with different chargers, ruling that out as a cause. As soon as power was connected, the power light blinked at around once…
Category: electronics
Code review of sample code running in a million places, with shocking results.
There are a bunch of complete build logs available for the Dactyl Manuform and similar mechanical keyboards, so I wanted to focus on the specific design choices I made and why. Huge hat-tip to Zack Freedman, in particular with this video, which served as inspiration that I could pull this off. Why a mechanical keyboard?…
The Xiegu GSOC, marketed by Chongqing Xiegu Technology Co., Ltd, under the retail name Radioddity, gets billed as a “Universal controller” for ham radio. It boasts some impressive hardware, including a high-resolution touchscreen, dual-core processor, two different audio processors, and a custom-engineered control wheel smooth as butter. So naturally I had to tear it apart.
If you played pinball in the 80s, you know about 16-segment LED displays. They existed in the narrow technology window after mechanical switches and alarm-clock-style 7-segment displays, but before full dot-matrix displays or full video were feasible with off-the-shelf computer hardware. There’s something geekily charming about these old displays. So naturally, I wanted to have…
I picked this up from The Plasma Channel on YouTube (which is worth more than a look) How to Measure High Voltage with Spheres A (somewhat) standardized way to measure high voltages is to see how big an arc can be established between two one-inch conductive spheres. The roundness of the spheres normalizes against surface…
In the previous posting, I went over requirements for a DIY power supply build. Now on to the fun part–shopping! Case I wanted something fairly compact, but still nice looking. I ended up going with Jameco ABS Heavy-Duty Instrument Case. It’s a good quality build. In metric, it’s 200mm across, and 64mm tall, which is…
Building a power supply is a rite of passage for electronics experimenters. I grew up in an age where all power supplies, even “wall warts,” had heavy iron transformers. In the last decade or two, better power transistors have become available, making possible switching power supplies, which are much lighter. (Think of your laptop power…
Modern technology has exceeded my wildest dreams as a teenager struggling to build an electronics lab. With an Amazon.com order, one can have an entire electronics lab for next to nothing. As a teen, I paid a guy $100 for a used oscilloscope that took two adults to lift. These days, you can get a solid…
Here’s the manual I wish had been included with the 8x8x8 LED cube kit I picked up on Amazon. Technically there’s already a manual available if you know where to look, but it’s poorly translated and difficult to follow in places. There’s several very similar kits out there, but the LED assembly process is the same, as…
Another blast from the past, from the same era. This was a general-purpose gadget: a 5V power supply, plus bouncelsss switch, plus a variable frequency TTL square wave generator. This was one of my experiments with making my own circuit boards, starting with copper cladded boards, drawing on the circuit paths with an inert ink, then…
A blast from the past! While going through old stuff, I found this device, which I designed and assembled maybe 25 years ago. I never used it. I think it didn’t work on the first try, and I got distracted by other shiny things. Story of my life. I thoughtfully left my future self a…
In the previous article I described how antennae work in terms of EM waves. But EM isn’t exactly a wave. Quantum aspects require modeling as particles. Photons. But I can’t really figure out how a photon traveling through space gets converted into an electron current in a wire. There are some cases where treating EM as…
A layman’s description of how antennas work, plus some related experiments. Physics is strange when you think about it. I’ve been working with electronics since I was about five. (Not an exaggeration. I “fixed†one of my two-battery-requiring cars with one good battery and some wire.) I sailed through high school electronics, and went on…