[Tech Minds] built one of those cheap automatic antenna tuners you see everywhere — this one scaled up to 350 watt capability. The kit is mostly built, but you do have to add the connectors and a few other stray bits. You can see how he did it in the video below.
What was very interesting, however, was that it wasn’t able to do a very good job tuning a wire antenna across the ham bands, and he asks for your help on what he should try to make things better.
There have been several attempts to make an unencumbered version of Windows. ReactOS is perhaps the best-known. You could also argue that Wine and its progeny, while not operating systems in the strictest sense of the word, might be the most successful. Joining the fray is Free95, a GPL-3.0 system that, currently, can run simple Windows programs. The developer promises to push to even higher compatibility.
As you might expect, the GitHub site is calling for contributors. There will be a lot to do. The src subdirectory has a number of files, but when you consider the sheer volume of stuff crammed into Windows, it is just a minimal start.
Science fiction authors and readers dream of travelling at the speed of light, but Einstein tells us we can’t. You might think that’s an arbitrary rule, but [FloatHeadPhysics] shows a different way to think about it. Based on a book he’s been reading, “Relativity Visualized,” he provides a graphic argument for relativity that you can see in the video below.
The argument starts off by explaining how a three-dimensional object might appear in a two-dimensional world. In this world, everything is climbing in the hidden height dimension at the exact same speed.
Continue reading “You Are Already Traveling At The Speed Of Light”
If you’ve ever been configuring a router or other network device and noticed that you can set up IPv4 and IPv6, you might have wondered what happened to IPv5. Well, thanks to [Navek], you don’t have to wonder anymore. Just watch the video below.
We will warn you of two things. First, the video takes a long time to get around to what IPv5 was. In addition, if you keep reading, there will be spoilers.
You’ve doubtless seen those ubiquitous clock modules, especially when setting clocks for daylight savings time. You know the ones: a single AA battery, a wheel to set the time, and two or three hands to show the time. They are cheap and work well enough. But [Playful Technology] wanted to control the hands with an Arduino directly and, in the process, he shows us how these modules work.
If you’ve never studied the inside of these clock modules, you may be surprised about how they actually work. A crystal oscillator pulses a relatively large electromagnet. A small plastic gear has a magnetic ring and sits near the electromagnet.
Each time the polarity of the electromagnet flips, the ring turns 180 degrees to face the opposite magnetic pole to the electromagnet. This turns the attached gear which is meshed with other gears to divide the rotation rate down to once per 24 hours, once per hour, and once per minute. Pretty clever.
That makes it easy to control the hands. You simply detach the electromagnet from the rest of the circuit and control it yourself. The module he used had a mechanical limitation that prevents the hands from moving well at more than about 100 times normal speed.
We wondered how he made the hands reverse and, apparently, there is a way to get the drive gear to move in reverse, but it isn’t always reliable. Of course, you could also replace the drive mechanism with something like an RC servo or other motor and it sounds like he has done this and plans to show it off in another video.
We’ve seen the opposite trick before, too. If you really want an easy-to-control analog clock, try this one Continue reading “Clock Mechanism Goes Crazy For Arduino”
Small cylindrical parts are often formed through deep drawing — a process by which a punch forms the finished piece from a flat sheet of metal using a forming die. If it sounds like that stresses the metal, it does. But researchers at Fraunhofer have found a way to reduce friction protecting both the material and the tools that do the forming. The process — known as VibroDraw — uses ultrasonic vibrations at around 500 Hz.
Researchers claim a 20% reduction in friction now, and it may be possible to go even further. With less friction, it is possible to do a deeper draw in a single stage. It also creates less heat which is good for tool life and prevents overheating lubricant. The process has a patent if you want more details. You might need to brush up on your German, though. Unsurprisingly, the vibrations are from a piezoelectric transducer.
Copper is soft enough to use 3D printed dies. We don’t know if this technique would help with that or not. Then there’s hydroforming. If you have any results using ultrasonics with these or any other techniques, be sure to let us know.
Movies mirror the time they were made. [ErnieTech] asserts that we can see what people thought about computers back in 1957 by watching the classic Spencer Tracy/Katharine Hepburn movie “Desk Set.” What’s more, he thinks this might be the first movie appearance of a human-like computer. On a side note, in the UK this movie was known as “The Other Woman.”
The story is about an MIT computer expert computerizing a broadcasting company who, of course, finds romance and, at least towards the end, comedy.
Continue reading “Fictional Computers: EMERAC Was The Chatbot Of 1957”
