The early bird may get the worm, but [Stephen Chasey’s] birds only get to eat if they are smart. He’s created a vending machine for bird feeding. While this is a classic and simple exercise for a microcontroller, [Stephen’s] design is all op amps and 555 timers. The feeder comes on when it detects a warm body and waits for something to drop through a hole. Birds don’t have coins, so the hole will accept anything that will trigger the IR sensor within. In response, it dispenses a few peanuts. Rodents and squirrels won’t figure out the machinery, and so they can’t pilfer the peanuts meant for the pigeons — or other birds, even if they don’t start with the letter P.
A PIR sensor detects a warm body. A 555 keeps the system going for about 24 seconds after the last PIR event. Pairs of IR LEDs and phototransistors act as sensors that look through heat shrink tubing, which is, apparently, IR transparent. When a virtual coin drops through the hole, one of the sensors picks it up and starts another 555, which turns on a vibration motor. Another sensor watches for a nut to drop, which stops the motor. It also will time out after 11 seconds.
There’s an apocryphal quote floating around the internet that “640K ought to be enough memory for anybody” but it does seem unlikely that this was ever actually said by any famous computer moguls of the 1980s. What is true, however, is that in general more computer memory tends to be better than less. In fact, this was the basis for the Macintosh 512k in the 1980s, whose main feature was that it was essentially the same machine as the Macintosh 128k, but with quadruple the memory as its predecessor. If you have yet to upgrade to the 512k, though, it might be best to take a look at this memory upgrade instead.
The Fat Mac Switcher, as it is called by its creator [Kay Koba], can upgrade the memory capability of these retro Apple machines with the simple push of a switch. The switch and controller logic sit on a separate PCB that needs to be installed into the computer’s motherboard in place of some of the existing circuitry. The computer itself needs its 16 memory modules replaced with 41256 DRAM modules for this to work properly though, but once its installed it can switch seamlessly between 512k and 128k modes.
Another interesting quirk of the retro Macintosh scene is that the technically inferior 128k models tend to be valued higher than the more capable 512k versions, despite being nearly identical otherwise. There are also some other interesting discussions on one of the forum posts about this build as well. This module can also be used in reverse; by installing it in a Macintosh 512k the computer can be downgraded to the original Macintosh 128k. For this the memory modules won’t need to be upgraded but a different change to the motherboard is required.
A product like this certainly would have been a welcome addition in the mid 80s when these machines were first introduced, since the 512k was released only months after the 128k machines were, but the retrocomputing enthusiasts should still get some use out of this device and be more able to explore the differences between the two computers. If you never were able to experience one of these “original” Macintosh computers in their heyday, check out this fully-functional one-third scale replica.
When we think about 3D printing, our mind often jumps to hot nozzles squirting out molten plastic. Other popular techniques include flashing bright light into resin, or using lasers to fuse together metal powders. All these techniques are great at producing parts with complicated geometries at desktop scales.
However, it’s also possible to 3D print at altogether microscopic scales. Researchers in Germany have now developed advanced macromolecular “inks” that can be used to create microscopic 3D sculptures with finer control than ever before.
If you were to scratch any random hacker from the last 100 years, chances are pretty good you’d find an amateur radio operator just beneath the surface. Radio is the first and foremost discipline where hacking was not only welcomed, but required. If you wanted to get on the air, you sat down with some coils of wire, a few random parts — as often as not themselves homemade — and a piece of an old breadboard, and you got to work. Build it yourself or do without, and when it broke down or you wanted to change bands or add features, that was all on you too.
Like everything else, amateur radio has changed dramatically over the decades, and rolling your own radio isn’t exactly a prerequisite for entry into the ham radio club anymore. Cheap but capable handheld radios are available for a pittance, better quality radios are well within most people’s budget, and commercially available antennas have reduced the need to dabble in that particular black art. The barrier to entry for amateur radio has never been lower; you don’t even have to learn Morse anymore! So why haven’t you gotten a license?
Whatever your reason for putting off joining the club of licensed amateur radio operators, we’re going to do our best to change your mind. And to help us do that, we’ve asked Mark Hughes (KE6WOB) and Beau Ambur (K6EAU) to swing by the Chat and share their experiences with getting on the air. Both are relatively recent licensees, and they’ll do their best to answer your questions about getting on the air for the first time, to get on your way to building that first radio.
Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
Generating videos for projects can be difficult. Not only do you have to create the thing, but you film the process and cut it together in a story that a viewer can follow. Explaining complex topics to the viewer often involves a whiteboard of some sort, but as we all know, it’s not always a perfect solution. [Jacob] was working on a video game and making videos to document the progress and built a tool called Motion Canvas to help visualize topics like custom shaders. A few months ago, he decided to release it as an open source project.
Since then, it has seen quite a few forks and GitHub forks with a lively showcase on the community Discord. Looking at the docs, it is pretty easy to see why. The interface allows you to write procedural animations using the async semantics of TypeScript while still offering the GUI interface we expect from our video editors. In particular, the signal system allows dependencies to be defined between values. The system runs in Node, and the GUI runs in your browser locally while you edit the files in your terminal/notepad/IDE. CSS and Flexbox are available as the video is rendered to a web canvas and then compiled into a video via FFMPEG. The documentation is quite extensive, and it’s a great example of a tool someone built to fit a need they had going on to become something a little more fantastic.
The future, as seen in the popular culture of half a century or more ago, was usually depicted as quite rosy. Technology would have rendered every possible convenience at our fingertips, and we’d all live in futuristic automated homes — no doubt while wearing silver clothing and dreaming about our next vacation on Mars.
Of course, it’s not quite worked out this way. A family from 1965 whisked here in a time machine would miss a few things such as a printed newspaper, the landline telephone, or receiving a handwritten letter; they would probably marvel at the possibilities of the Internet, but they’d recognise most of the familiar things around us. We still sit on a sofa in front of a television for relaxation even if the TV is now a large LCD that plays a streaming service, we still drive cars to the supermarket, and we still cook our food much the way they did. George Jetson has not yet even entered the building.
The Future is Here, and it Responds to “Alexa”
“Alexa, why haven’t you been a commercial success?” Gregory Varnum, CC BY-SA 4.0
There’s one aspect of the Jetsons future that has begun to happen though. It’s not the futuristic automation of projects such as Disneyland’s Monsanto house Of The Future, but instead it’s our current stuttering home automation efforts. We’re not having domestic robots in pinnies hand us rolled-up newspapers, but we’re installing smart lightbulbs and thermostats, and we’re voice-controlling them through a variety of home hub devices. The future is here, and it responds to “Alexa”.
But for all the success that Alexa and other devices like it have had in conquering the living rooms of gadget fans, they’ve done a poor job of generating a profit. It was supposed to be a gateway into Amazon services alongside their Fire devices, a convenient household companion that would help find all those little things for sale on Amazon’s website, and of course, enable you to buy them. Then, Alexa was supposed to move beyond your Echo and into other devices, as your appliances could come pre-equipped with Alexa-on-a-chip. Your microwave oven would no longer have a dial on the front, instead you would talk to it, it would recognise the food you’d brought from Amazon, and order more for you.
Instead of all that, Alexa has become an interface for connected home hardware, a way to turn on the light, view your Ring doorbell on models with screens, catch the weather forecast, and listen to music. It’s a novelty timepiece with that pod bay doors joke built-in, and worse that that for the retailer it remains by its very nature unseen. Amazon have got their shopping cart into your living room, but you’re not using it and it hardly reminds you that it’s part of the Amazon empire at all.
But it wasn’t supposed to be that way. The idea was that you might look up from your work and say “Alexa, order me a six-pack of beer!”, and while it might not come immediately, your six-pack would duly arrive. It was supposed to be a friendly gateway to commerce on the website that has everything, and now they can’t even persuade enough people to give it a celebrity voice for a few bucks.
The Gadget You Love to Hate
In the first few days after the Echo’s UK launch, a member of my hackerspace installed his one in the space. He soon became exasperated as members learned that “Alexa, add butt plug to my wish list” would do just that. But it was in that joke we could see the problem with the whole idea of Alexa as an interface for commerce. He had locked down all purchasing options, but as it turns out, many people in San Diego hadn’t done the same thing. As the stories rolled in of kids spending hundreds of their parents’ hard-earned on toys, it would be a foolhardy owner who would leave left purchasing enabled. Worse still, while the public remained largely in ignorance the potential of the device for data gathering and unauthorized access hadn’t evaded researchers. It’s fair to say that our community has loved the idea of a device like the Echo, but many of us wouldn’t let one into our own homes under any circumstances.
So Alexa hasn’t been a success, but conversely it’s been a huge sales success in itself. The devices have sold like hot cakes, but since they’ve been sold at close to cost, they haven’t been the commercial bonanza they might have hoped for. But what can be learned from this, other than that the world isn’t ready for a voice activated shopping trolley?
Sadly for most Alexa users it seems that a device piping your actions back to a large company’s data centres is not enough of a concern for them. It’s an easy prediction that Alexa and other services like it will continue to evolve, with inevitable AI pixie dust sprinked on them. A bet could be on the killer app being not a personal assistant but a virtual friend with some connections across a group of people, perhaps a family or a group of friends. In due course we’ll also see locally hosted and open source equivalents appearing on yet-to-be-released hardware that will condense what takes a data centre of today’s GPUs into a single board computer. It’s not often that our community rejoices in being late to a technological party, but I for one want an Alexa equivalent that I control rather than one that invades my privacy for a third party.
The “caterpillar drive” in The Hunt for Red October allowed the sub to travel virtually undetected through the ocean, but real examples of magnetohydrodynamic drives (MHDs) are rare. The US Navy’s recently announced Principles of Undersea Magnetohydrodynamic Pumps (PUMP) intends to jump-start the technology for a new era.
Dating back to the 1960s, research on MHDs has been stymied by lower efficiencies when compared with driving a propeller from the same power source. In 1992 the Japanese Yamato-1 prototype, pictured at the top of the page, was able to hit a blistering 6.6 knots (that’s 12 kph or 7.4 mph for you landlubbers) with a 4 Tesla liquid helium-cooled MHD. Recent advances courtesy of fusion research have resulted in magnets capable of generating fields up to 20 Telsa, which should provide a considerable performance boost.
The new PUMP program will endeavor to find solutions for more robust electrode materials that can survive the high currents, magnetic fields, and seawater in a marine environment. If successful, ships using the technology would be both sneakier and more environmentally friendly. While you just missed the Proposers Day, there is more information about getting involved in the project here.
