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Zoom Control Box Helps Keep Meetings On Track

For many people, the biggest change of 2020 has been adjusting to a glut of online teleconferences as a part of daily working life. [p_leriche] has had to adjust the way church services are conducted, and found managing a complicated streaming meeting setup to be complicated at best. To ease the workload on the presenter, he created a simple Zoom control box. At its heart, the box is little more than a fancy keyboard. An Arduino Pro Micro is hooked up to a series of brightly colored pushbuttons, each labelled with regularly used Zoom functions. The Pro Micro is programmed to fire off the corresponding keyboard shortcuts when the buttons are pressed, activating the relevant function. It might be a simple build, but it greatly reduces the hand gymnastics required mid-presentation, and we’re sure the users greatly appreciate the new hardware. While this is a quick-and-dirty build thrown together in a basic enclosure, macro keyboards can be both useful and attractive if you so desire. I
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This Week in Security: Platypus, Git.bat, TCL TVs, and Lessons From Online Gaming

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Git’s Large File System is a reasonable solution to a bit of a niche problem. How do you handle large binary files that need to go into a git repository? It might be pictures or video that is part of a project’s documentation, or even a demonstration dataset. Git-lfs’s solution is to replace the binary files with a taxt-based pointer to where the real file is hosted. That’s not important to understanding this vulnerability , though. The problem is that git-lfs will call the main git binary as part of its operation, and when it does so, the full path is not used. On a Unix system, that’s not a problem. The $PATH variable is used to determine where to look for binaries. When git is run, /usr/bin/git is automagically run. On a Windows system, however, executing a binary name without a path will first look in the current directory, and if a matching executable file is not found, only then will the standard locations be checked. You may already see the problem. If a repository contains
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Easy Carrier Board For the Compute Module 4 Shows You Can Do It, Too

The Raspberry Pi Compute Module 4 has got many excited, with a raft of new features bringing exciting possibilities. However, for those used to the standard Raspberry Pi line, switching over to the Compute Module form factor can be daunting. To show just how easy it is to get started, [timonsku] set about producing a quick and dirty carrier board for the module at home . The Twitter thread goes into further detail on the design of the board. The carrier features HDMI, USB-A and USB-C ports, as well as a microSD slot. It’s all put together on a single-sided copper PCB that [timonsku] routed at home. The board was built as an exercise to show that high-speed signals and many-pin connectors can be dealt with by the home gamer, with [timonsku] sharing tips on how to get the job done with cheap, accessible tools. The board may look rough around the edges, but that’s the point. [timonsku] doesn’t recommend producing PCBs at home when multi-layer designs can be had cheaply from overseas. I
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Tracking Drone Flight Path Via Video, Using Cameras We Can Get

Calculating three-dimensional position from two-dimensional projections are literal textbook examples in geometry, but those examples are the “assume a spherical cow” type of simplifications. Applicable only in an ideal world where the projections are made with mathematically perfect cameras at precisely known locations with infinite resolution. Making things work in the real world is a lot harder. But not only have [Jingtong Li, Jesse Murray et al.] worked through the math of tracking a drone’s 3D flight from 2D video, they’ve released their MultiViewUnsynch software on GitHub so we can all play with it. Instead of laboratory grade optical instruments, the cameras used in these experiments are available at our local consumer electronics store. A table in their paper Reconstruction of 3D Flight Trajectories from Ad-Hoc Camera Networks (arXiv:2003.04784) listed several Huawei cell phone cameras, a few Sony digital cameras, and a GoPro 3. Video cameras don’t need to be placed in any p
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Domino Clock Tells The Time In Style

It seems there are as many ways to display the time as there are ways to measure it in the first place. [Kothe] saw a fancy designer domino clock, and wanted a piece of the action without the high price tag. Thus, the natural solution was to go the DIY route. An Arduino Nano is the heart of the build, paired with a DS1307 RTC for accurate timekeeping. The case of the clock consists of a 3D printed housing, fitted with layers of lasercut acrylic. Behind this, a smattering of WS2812B addressable LEDs are fitted, which shine through the translucent grey plastic of the front panel. This enables each LED to light up a dot of the domino, while remaining hidden when switched off. Reading the time is as simple as counting the dots on the dominoes. The first domino represents hours, from 1 to 12, while the second and third dominoes represent the minutes. As a timepiece, the domino clock serves well as a stylish decor piece, and could also be a fun way to teach kids about electronics and telli
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Rotating Magnetic Fields, Explained

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If you made a motor out of a magnet, a wire coil, and some needles, you probably remember that motors and generators depend on a rotating magnetic field. Once you know how it works, the concept is pretty simple, but did you ever wonder who worked it all out to start with? Tesla figures into it, unsurprisingly. But what about Michael Dobrowolsky or Walter Bailey? Not common names to most people. [Learn Engineering] has a slick video covering the history and theory of rotating magnetic field machines , and you can watch it below. Motors operated on direct current were not very practical at the time and caused a jerky motion. However, Tesla and another inventor named Ferraris realized that AC current could cause a rotating magnetic field without a moving commutator. Tesla’s motor used two AC currents with a 90-degree phase difference produced by his two-phase generator. Ferraris used a single phase along with an inductor to create the phase difference. However, two-phase motors have li
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Bringing An IBM Model F Into 2020

We know that the Hackaday family includes many enthusiasts for quality keyboards, and thus mention of the fabled ‘boards of yore such as the IBM Model F is sure to set a few pulses racing. Few of us are as lucky as [Brennon], who received the familial IBM PC-XT complete with its sought-after keyboard . This Model F has a manufacture date in March 1983, and as a testament to its sturdy design was still in one piece with working electronics. It was however in an extremely grimy condition that necessitated a teardown and deep clean. Thus we are lucky enough to get a peek inside, and see just how much heavy engineering went into the construction of an IBM keyboard before the days of the feather-light membrane devices that so many of us use today. There follows a tale of deep cleaning, with a Dremel and brush, and then a liberal application of Goo Gone. The keycaps had a long bath in soapy water to remove the grime, and we’re advised to more thoroughly dry them should we ever try this as s
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