The second Friday the 13th of 2026 is here, a date synonymous with bad luck for the superstitious. Friday the 13th has a reputation as a day of bad luck mainly because two separate superstitions merged over time: fear of the number 13 and fear of Friday. When they combined, the date became especially ominous →
This is a viral class A amplifier from https://www.facebook.com/share/p/1MWzg9TXxc/ This is a classic “minimalist” single-ended Class A MOSFET amplifier. While it is praised for simplicity, it is inherently inefficient and prone to significant distortion. In this design, the MOSFET (IRF530) is always “on,” acting as a variable resistor that pulls current through the 15 ohms →
This posting is here to collect cyber security news in March 2026. I post links to security vulnerability news to comments of this article. You are also free to post related links to comments. →
I just read an interesting article How to Write a Good Spec for AI Agents article on using AI to write software. That article is pretty long, so I decided that a compact overview would be useful. I started to pick what I think was most important and decided to turn my notes/picks to this →
At CES’26 this year Donut Lab caused quite the furore when they unveiled what they claimed was the world’s first production-ready solid state battery, featuring some pretty stellar specifications. Since then many experts and enthusiasts in the battery space have raised concerns that this claimed battery may not be real, or even possible at all. →
I have written about ground loop problems for over 25 years. I have published a lot of material over the years in this blog and in the documents section. I have had over years plans to combine and update the material to a physical book or e-book format. Ground Loops Demystified publication is now available →
I saw this circuit in facebook at https://www.facebook.com/share/p/1FF5z48oYV/. The screen capture is included here under fair use (commentary and critique). The good thing is that this is a simple circuit, but the disadvantage is that there is NO sound out with this design. – there is a battery drawn without clear indication of the operating →
Cybersecurity can be a laughing matter. Epic FAIL comic strip is a new comic strip series related to cybersecurity topics is now available on-line at https://www.instagram.com/storax_ltd/ The comic can be also found at Storax homepage at https://stor.ax/epicfail/index.html →
Facebook viral circuit from https://www.facebook.com/share/p/1buynd6caE/ analysis Let’s break this down calmly, because this circuit looks cooler than it actually is It works, but in the “Facebook shorts” sense, not in an engineering sense. It’s a very simple sound-reactive LED circuit. Big problem: There are NO current-limiting resistors for the LEDs. It might work for some →
In what country this is the recommended practice? Picture source: Facebook https://www.facebook.com/share/p/1DrRjhJH2r/ I have been reached that If you should not use a knot for cable strain relief. ⚠️ Important: If this is a 230 V / mains-powered device, proper mechanical strain relief is mandatory for safety and compliance. A knot is not a safe →