"Has your washing machine broken down, or is your electric kettle, laptop or mobile phone refusing to work?
Well if you live in Austria, the government will pay up to €200 ($219; £173) towards getting it repaired.
The Repair Bonus voucher scheme is aimed at trying to get people to move away from throwing away old electrical appliances - and focusing on getting things mended."
The history of electromagnetism is truly bizarre when you think about it. The theory was essentially 100% complete in 1873 in A Treatise on Electricity and Magnetism. Well, supposedly complete - as nobody could really understand its content fully, not even the author. Maxwell introduced the displacement current as a small technical fix, but failed to realize it could generate E&M waves. The reanalysis of the book took physicists 10 to 20 years. Pupin traveled from US to Cambridge because he wanted to ask the question "WTF is the book?" personally to Maxwell. The young Heaviside said understanding this book was his life goal (realized during 1880-1890). During this period, nobody really knew for sure that E&M waves exist. Even after Hertz demostrated E&M waves, physicists all believed it was a short-range effect like light. Then in 1895 Marconi discovered a practical longwave ratio transmitter by random tinkering. After he heard telegraph transmitters are grounded, he tried it too, accidentally inventing the monopole antenna by sheer luck (and also made it the first case of "cargo cult grounding" in RF electronics, today still practiced by many technicians that should know better). Except that it actually worked for him spectacularly because of a quirk of the Earth's atmosphere. Physicists had absolutely no idea about it and the explanation at that time by physics guru Sommerfeld (the Zenneck surface wave solution to Maxwell's equation) was completely wrong. In 1905, there was already special relativity but still little understanding about antennas and waveguides in general. Some people actually argued that special relativity made E&M simpler... #electronics
I had an epiphany today: Mastodon is my makerspace. I haven't been able to find a makerspace in this area since we moved here in '22, and that's been bugging me. But I scroll through Mastodon and see people's printing, woodworking, electronics, and welding projects, and I admire them, and sometimes I ask questions and learn new techniques. And when I post my own, people do the same.
So, this was my favorite toy growing up... A "160-in-One" Electronics Kit from #RadioShack. The kit had instructions on how to build a simple, low-powered broadcast radio (and I, of course, had cut off the jack of a microphone cord, which I stripped and added as an sound input). Not satisfied with the range of my "pirate radio station," I added a few extra capacitors, used a stainless steel window screen as an antenna, and soon the neighbors were complaining to my grandparents. Mission accomplished!
Fun random fact: the sample rate of Audio CD format is 44100Hz. The Nyquist frequency for audible sound is roughly double the upper limit of human hearing, which is 20kHz.
So why is the CDDA sample rate more than 40kHz, but only a little bit more?
The prime factorization of 44100 is 2^2•3^2•5^2•7^2, which gives a LOT of options for computationally cheap downsampling and playback speed reduction. 😁
I wrote a blog post about the surprisingly deep challenges involved when you dim LEDs with PWM, and the calculator tool I wrote to help solve this problem.
cyclists of the fediverse: is there any kind of device that does not yet exist, but you wish existed, that would improve your cycling experience/safety?
would be cool if a team of undergrads could make it in two months for an embedded system course (we're brainstorming)
Parasitic and ESD diodes that don't officially exist are everywhere in semiconductors, so almost all chips have on-die temperature sensors if you abuse them carefully enough. How does the 1970s US military measure junction temperature in mighty MIL-STD-883 - remove power, and immediately (within microseconds) capture the substrate/body/ESD diode bias voltage in a sample-and-hold circuit before it cools down. Great accuracy. Analog Devices retested the idea recently and found it still works great today. https://www.analog.com/en/analog-dialogue/articles/esd-diode-doubles-as-temperature-sensor.html#electronics
The beast grows. My #68k computer is getting closer to the finish line. Chewed through a lot this weekend!
Adjusted common ROM address lines, they were going over the chips and it bothered me. Plus, I'll probably be bouncing those in and out for a while until I venture to programming via a boot loader.
Wired up the many buffered address lines. I did a continuity check last night and it looks good so far. :blobsweat:
Finished the control line buffer and distributed the outputs. I used a big fat purple wire for /DTACK out of respect (or disrespect depending on whom you ask) :blobcatangel:
Finished the /IACK decoder
Wired up the GAL inputs and some of the outputs
New TODOs queued up:
Finish connecting the 68681 serial chips
Finish placing decoupling caps
Replace 7404 with open-drain 7405 variant to work properly with the /RESET line
Researching inductor parasitics, I found this cool manuscript by radio amateur David W Knight. To visualize the E-field in and around coils, they used a gas discharge tube! Even if you're not up for the math, check out the PDF linked below for a few more cool pictures 😄
At my work, I wrote #KiMesh, a security mesh generator plugin for #KiCad. A security mesh is a set of labyrinth-like traces covering an area on a #PCB to detect someone drilling or sawing through it. I'm happy to report, that you can now install KiMesh on KiCad nightly through the built-in plugin manager.
Fun fact: Just like microcontrollers, the fuse bits in desktop CPUs can occasionally get loose, causing single-bit flips. This is likely responsible for many strange CPUIDs in the wild, some reported cases include "GenuineIotel" CPUs [1] and a "Intel Core i4" CPU. [2] #electronics
KiCad needs funding for its next release cycle.
If you do PCB design, esp. if its your job, consider donating.
Even if you don't use KiCad yourself as your main tool (like myself) its still an incredibly important piece of infrastructure for the industry as a whole.
From the department of cursed IC packages ... the DIP20 with odd pins, and a heatsink screw. Plessey SL414A, single channel 3W audio power amplifier. #cursedChips#CursedPackages#Electronics
New boards arrived with silk made in #gerbolyze from a sheet of patterned #origami paper. The silkscreen covers the mostly empty bottom layer, with the top silk containing all component references. The footprint in the middle is a socket for a Würth WR-WST direct-to-board connector that I'm starting to use as a much cheaper and more convenient alternative to the offerings of Tag-Connect.
"Over 3 billion kilograms of valuable electronics inside children’s toys are thrown away each year, and very few people are aware of this hidden e-waste"
Practising Permacomputing: Call for workshop participants
"This autumn is dedicated to Practising Permacomputing; a concept and a nascent community of practice-oriented around issues of resilience and regenerativity in computer and network technology derived, among others, from permaculture principles. As part of this community, space is offered to makers and thinkers in digital culture (and other connected areas) to put the fundamentals and applications of #permacomputing into practice through a series of workshops, a meetup, and a concluding day of public presentations with guests. Join us to explore permacomputing futures!"
Do I know anyone who has experience developing with FreeRTOS or bare metal firmware on STM32MP1 MPUs?
(specifically the MP1 family, not general STM32 MCUs, and NOT using U-Boot/Linux, or anything else that does SDRAM bringup for you before handing off execution)
A couple of weeks ago I finished a beast of a project.
The interactive installation (titled InStability) is an artistic endeavor to demonstrate how seismic stations in Iceland detect earthquakes.
Visitors are invited to touch the map, triggering "earthquakes", and observe how LEDs, representing seismic and GPS stations, light up as the seismic waves propagate across Reykjanes peninsula.
I love all the diversity and representation in Star Trek! It's fun watching bigots squirm. I'd much rather they reflect on their bigoted opinions, and strive to better themselves. But if they refuse to do that, then watching them squirm is the next best thing. #StarTrek