With some time to kill and an array of old Apple computers on hand, [Pierre Dandumont] wondered if he could continuously upgrade a single OS drive from the oldest system he had, System 7.1 on a Performa 630, to the latest version of MacOS on a MacBook Air. He recalled watching an old video which demonstrated a continuous upgrade from DOS to Windows 10 (we think this video from 2016 may be the one), which gave him the inspiration for this journey. [Pierre] documents his efforts on his blog (in French; English translated link is here).
Along the way, he installed 24 different operating systems
System 7.1.2, 7.5
Mac OS 7.6
Mac OS 8.0, 8.1, 8.5, 8.6
Mac OS 9.0, 9.1, 9.2
Mac OS X 10.0 – 10.11
macOS 10.12, 10.13
on seven Mac computers
Performa 630 (ca. 1994, Motorola 68040)
Power Mac G3 Beige (ca. 1997, Motorola PowerPC 730)
Power Mac G3 Blue (ca. 1999, Motorola PowerPC 730)
Power Mac G4 Digital Audio (ca. 2001, Motorola PowerPC 7400)
Mac mini G4 (ca. 2005, Motorola PowerPC 7447)
Mac mini 2009 (Intel Core 2 Duo Penryn)
MacBook Air 2012 (Intel Core i5/i7)
across three of the four processor families spanned by the Macintosh line of computers since their introduction in 1984. You can see in the lead photo the success, where the Mac OS 8 search tool Sherlock is shown in the dock of a MacBook Air running High Sierra.
If you’ve been following the news, you can’t have missed the series of floods, droughts, and wildfires that have occurred seemingly in all corners of the world. Coming on the heels of a Northern Hemisphere winter that had its own extreme weather events, it would be perhaps foolhardy not to by now take climate change seriously. You may also have seen the news about a return to a 1970s paper in which MIT crystal-ball-gazers predicted the collapse of our civilisation in the mid-21st century, and a review based upon the empirical data gathered since then which concluded that we could be right on track with that prediction set to happen in about 2040.
It’s sobering stuff, and something which could so easily form the basis of many a Hollywood apocalyptic disaster movie. But sitting here in 2021 amid extreme weather events and a global pandemic it’s certainly something to think about. It’s not as though we’re riding biogas-powered weapon cars through the post-apocalyptic desert just yet though, we still have a chance to do something to avert catastrophe and no doubt over the next decade a raft of changes will reduce our CO2 impact and make our infrastructure more resilient to stave off any coming crises.
When shooting archery, if you want to be accurate, you need arrows of uniform specification and quality. One important part of this is making sure each arrow has a spine of similar stiffness. Traditionally, this is checked in a very analog way by using weights and measuring deflection of the arrow spine, but it can be done electronically too with this tester from [dvd8n].
The principle of operation is simple. The arrow is held up by two supports, 28 inches apart. The user then presses down in the center of the arrow, deflecting it by a 1/2 inch where itreaches a stop , and load cells at either end of the tester measure the force required to deflect the arrow by the set amount.
It allows arrows to be electronically measured in a fashion that is compatible with existing standards for measurement. The Arduino hardware which measures the load cells can also easily run conversion maths to display the arrow’s measured stiffness in whatever common spine measurement standard is desired. The system can also weigh the arrows, a useful thing to know for the home fletcher.
Over the last few months we’ve been keeping an eye on WiFiWart, an ambitious project to develop a Linux single-board computer (SBC) small enough to fit inside a USB wall charger. Developer [Walker] says the goal is to create an easily concealable “drop box” for penetration testing, giving security researchers a valuable foothold inside a target network from which to preform reconnaissance or launch attacks. Of course, we don’t need to tell Hackaday readers that there’s plenty of other things you can do with such a tiny open hardware Linux SBC.
Today we’re happy to report that [Walker] has gotten the first version of the board booted into Linux, though as you might expect given a project of this complexity, there were a few bumps along the way. From the single missing resistor that caused U-Boot to throw up an error to the finer points of compiling the kernel for an embedded board, the latest blog post he’s written up about his progress provides fascinating insight into the little gotchas of bringing up a SBC from scratch.
Once the board was booted into Linux, [Walker] started testing out different aspects of the system. A memory benchmark confirmed the finicky DDR3 RAM was working as expected, and he was able to load the kernel modules for the dual RTL8188 interfaces and connect to a network. While the two WiFi modules are currently hanging off the board’s full-sized USB ports, they will eventually be integrated into the PCB.
Critically, this prototype board is also allowing [Walker] to get an idea of what the energy consumption of the final hardware might be. Even at full tilt, this larger board doesn’t go over 500 mA at 5 VDC; so if he designs the power supply with a maximum output of 1 A, he should have a nice safety margin. As mentioned in the previous post, the plan is currently to put the PSU on its own board, which will allow more effective use of the charger’s internal volume.
The build runs twelve servos – three per leg – to enable for a great range of movement for each limb. The servos are all controlled by an Arduino Uno fitted with an Arduino Sensor Shield. Everything is fitted together with a 3D printed chassis and limb segments that bolt directly on to the servo output shafts. This is a common way of building quick, easy, lightweight assemblies with servos, and it works great here. Inverse kinematics is used to calculate the required motions of each joint, and the robot can take steps from 1 to 4cm long in a variety of gaits.
We’d love to see a few sensors and a battery pack added on to allow the ‘bot to explore further in an untethered fashion. [Technovation] has left some provision to mount extra hardware, so we look forward to seeing what comes next.
You can hardly mention the sudo command without recalling the hilarious XKCD strip about making sandwiches. It does seem like sudo is the magic power to make a Linux system do what you want. The only problem is that those superpowers are not something to be taken lightly.
If you are surfing the web, for example, you really don’t want to be root, because if someone naughty takes over your computer they could do a lot more harm with your root password. But still, there are times when you want to run certain commands that are normally root-only and don’t want to bother with a password. Luckily, sudo can handle that use case very easily.
As a simple example, suppose you like to shut your computer down at the end of the day. You run the shutdown command from the terminal but it doesn’t work because you aren’t root. You then have to do it again with sudo and if you haven’t logged in lately, provide your password. Ugh.
In a perfect world, we’d all have laser cutters and could pop intricate designs out of acrylic sheets with just a few clicks of the mouse. But in reality, most of us have to make do with the pedestrian tools we have at hand. For many, that might even mean everything has to be done by hand. Luckily, [Eric Strebel] has been working on a series of videos that cover how you can make professional looking parts out of acrylic using a wide array of common tools.
The first video demonstrates how a simple cube can be constructed by a band saw, a table saw, and if need be, with hand tools. You might think the two power saws would have similar results, but as [Eric] explains, the table saw ends up being far more accurate and requires less post-processing to get a smooth edge. Ideally you’d run the cut pieces through a router to bevel them, but that’s a tall order for many home gamers.
As for the hand tool approach, scoring and snapping the sheets ends up making a surprisingly clean break that can actually be cleaner than the edge you’d get with a power tool. No matter how you cut them, [Eric] shows the proper way to apply the water-like solvent to your acrylic pieces to create a strong and visually attractive bond.
The next video in the series covers more advanced techniques that can still be pulled off without a top-of-the-line workshop. Sure the water-cooled acrylic bender he has is pretty slick, but if you can’t afford the $100 USD gadget, he shows you how to get similar results with an old toaster oven that you can pick up from the thrift store or even the side of the road. With some hand-made jigs and molds, you can warp and flex the heated plastic into whatever shape your project needs. Combining the tips from both videos, you might be surprised at what can be created with little more than a ruler, some hot air, and the appropriate techniques.