Kritik sah

Airborne micro particles can be a significant health hazard in a workshop, and thus it’s important to maintain a high standard of ventilation. But monitoring their concentration is also important, and thus there exists a range of sensors to help keep you safe. [WeSpeakEnglish] has taken this idea to the MAX, with a PM2.5 sensor that drives a very large wall mounted display. You’ll never be uncertain what the level is now! The standout feature of this thing is a huge addressable LED seven segment display PCB, upon the back of which sits a tiny Seeed Studio Xiao board to which the particle sensor is hooked up. The software displays the particle count, and handily changes the colour as the number creeps upwards. Meanwhile should you wish to log the readings, the USB exposes a serial port upon which they are placed. We can see this is a useful project for anywhere that is likely to have a high particle count, but it’s worth noting also that a large 7-segment display with...

If we care to cast an eye over the history of ubiquitous personal computing as we know it today, we might immediately point at the original IBM PC. After all, for most of us our machines share backward compatibility in some form through multiple generations back to that original box from 1981. But if we look at the things we use today and take for granted, from laser printers to graphics cards to the routers which power most of the Internet, they’re not from IBM at all. At the recent Vintage Computing Festival Berlin, [Michael Engel] delivered a talk naming a surprising progenitor for much of that technology, none other than Sun Microsystems. It all starts with [Andy Bechtolsheim], famously Sun’s co-founder, when at the end of the 1970s he was a postgraduate at Stanford University. Working on the Stanford University Network — SUN — project he designed a computer to be used as a workstation on the network. The processor of choice then was Motorola’s 68000...

The humble credit card reader — most of us have used hundreds, perhaps even thousands of them over the years. But even for folks like us, it’s not the sort of device we give a lot of thought to. It’s just a keypad, a display, and a magnetic stripe reader. How interesting could it possibly be? That may be true in some cases, but at least for the 1990s-era TRANZ 330, there’s a bit more to the story than that. As [CharlesD] explains, these particular readers are essentially complete Z80 computers just waiting to do something more exciting than processing PINs. In the case of this particular unit, the addition of a GPS module and some new code has turned it into an interactive guide to the solar system . Thanks to the UV erasable ROMs used in the TRANZ 330, loading new code on the device is easy enough. With a bit of educated poking around, [CharlesD] was able to map out what did what. Working from the basics of getting the display and keypad working, he moved onto...

In the open source world we are used to software being compiled from source for our particular distro, so while in a few cases an ancient release may still be in use, it’s just going to run on the latest distro version. But in the Windows world it’s rare for software to come with the source, so you’re left with a binary that will only run if your Windows version has the right APIs for it. Since the more recent versions of Windows dropped 16-bit support a while back, that means there must be a hard date set on the earliest Windows GUI application that can still run today. [Enlyth] decided to investigate . Given that the earliest API supported in WIndows 11 is the 32-bit version, the hunt led straight to either the first Windows NT release and ancestor of Windows 11, or the Win32s extension for WIndows 3.1. Thus a 1993 Win32S version of Freecell runs happily, but that want’s the end of the trail. Somewhere in the pre-release builds of Windows NT 3.1 would be the r...

There are some devices which achieve electronic immortality, it’s likely that you have used a few of them yourself. The 555 timer of course, or the 741 op-amp. [ElectronicsNotes] is here with another candidate that might not have been on your mind as you read the previous sentences, and it’s a transistor. The 2N3055 is an NPN power transistor, no,  THE NPN power transistor, that has found its way into an astounding array of devices over the last six decades or more. For such a ubiquitous device one might imagine that there’s not much new to know, but the video delivers on that front. Here as well as probably for you the 3055 has always been an epitaxial device whose quirks you likely know well, but originally it was something different. It used the hometaxial construction process on its launch in the early 1960s, but in the mid 1970s it was replaced by a version with the same capabilities but using the epitaxial process. The consequent higher Ft required modificatio...

Recently [Rod Burlamaqui] released the arc-rebar project on GitHub , enabling Intel GPUs to work significantly more efficiently if the system’s mainboard does not support resizable BAR. It does require a Debian or Ubuntu installation and of course a supported Intel GPU. Although the resizable base address register (ReBAR) feature has been part of the PCIe specification for a while, its use was quite limited until Intel released its Arc series of graphic cards. These use this feature to map much more of the GPU’s video RAM (VRAM) into the PC’s address space than the standard 256 MB, assuming that the system is capable of decoding addresses above 4 GB, i.e. allow for 64-bit BARs. For GPU manufacturers like AMD and Nvidia this wasn’t so much of an issue as their GPU designs developed in a world where ReBAR didn’t exist, while Intel’s new GPU generations were designed with ReBAR as a core feature, which naturally cripples performance if the mainboard d...