Every once in a while we get nostalgic for the old days of computing. Here, we’re getting nostalgic for a past that wasn’t even our own, but will probably bring a smile to all the German hackers out there. c’t magazine has its first issue available on their website (PDF, via FTP), and it’s worth checking out even if you can’t read a word of German.
It’s dated November/December 1983, and you’re definitely hopping in the WABAC machine here. The cover image is a terminal computer project that you’re encouraged to build for yourself, and the magazine is filled with those characteristic early-computer-era ads, many of them for the physical keyboards that you’d need to make such a device. Later on, c’t would provide plans for a complete DIY PC with plotter, one of which we saw still running at the 2015 Berlin Vintage Computer Festival.
The issue is chock-full of code for you to type out into your own computer at home. If you didn’t have a computer, there are of course reviews of all of the popular models of the day; the TRS-80 Model 100 gets good marks. And if you need to buy a BASIC interpreter, there’s an article comparing Microsoft’s MBASIC with CBM’s CBASIC. A battle royale!
Other hot topics include modifications to make your ZX81’s video output sharper, the hassle of having to insert a coded dongle into your computer to run some software (an early anti-piracy method), and even a computer-music band that had (at least) a Commodore 64 and a CBM machine in their groovy arsenal.
It’s no secret that we like old computers, and their associated magazines. Whether you prefer your PDP-11’s physical or virtual, we’ve got you covered here. And if your nostalgia leans more Anglophone, check out this Byte magazine cover re-shoot.
There are a lot of ways to measure energy usage in the home, but most of them involve handling mains voltage. Not only that, but sometimes they require handling mains voltage before it gets through a breaker panel or fuse box, meaning that if you make a mistake there are a lot of bad things that can happen. [Yonas] has been working on this problem, and has come up with a non-invasive, safer way to monitor electricity consumption without having to work directly on live wires.
Please note that you should still not be working on mains voltage without proper training, but if you have the required know-how then the installation should be pretty straightforward. The project is based on the Spark Core, and uses clamp-on current sensors to measure energy use. The sensors wrap around the mains cable, meaning you don’t have to disconnect anything to hook them up. The backend runs on a LAMP server which could be a Raspberry Pi if you have one. [Yonas] runs it on a hosted server as a matter of preference.
All of the source code for this is available, and assuming you can get your hands on the current sensors this could be a great way to get started monitoring your energy usage in the house. Be sure to check out the video below for a demonstration of the operation of this device. Of course, if you have a gas line you’ll need this energy monitoring setup too.
Continue reading “Non-Invasive Smart Electricity Meter”
What do you do when you’re dad’s a veterinarian, dumped an old x-ray machine in your garage, and you’re looking for an entry for The Hackaday Prize? Build a CT scanner, of course. At least that’s [movax]’s story.
[movax]’s dad included a few other goodies with the x-ray machine in the garage. There were film cassettes that included scintillators. By pointing a camera at these x-ray to visible light converting sheets, [movax] can take digital pictures with x-rays. From there, it’s just building a device to spin around an object and a lot – a lot – of math.
Interestinly, this is not the first time a DIY CT scanner has graced the pages of Hackaday. [Peter Jansen] built a machine from a radiation check source, a CMOS image sensor, and a beautiful arrangement of laser cut plywood. This did not use a proper x-ray tube; instead, [Peter] was using the strongest legally available check source (barium 133). The scan time for vegetables and fruit was still measured in days or hours, and he moved on to build an MRI machine.
With a real source of x-rays, [movax]’s machine will do much better than anything the barium-based build could muster, and with the right code and image analysis, this could be used as a real, useful CT scanner.
People get CT and MRI scans every day, and when [Oliver] needed some medical diagnostic imaging done, he was sure to ask for the files so he could turn his skull into a printable 3D object.
[Oliver] is using three different pieces of software to turn the DICOM images he received from his radiologist into a proper 3D model. The first two, Seg3D and ImageVis3D, are developed by the University of Utah Center for Integrative Biomedical Computing. Seg3D stitches all of the 2D images from an MRI or CT scan into a proper 3D format. ImageVis3D allows [Oliver] to peel off layers of his flesh, allowing him to export a file of just his skull, or a section of his entire face. The third piece of software, MeshMixer, is just a mesh editor and could easily be replaced with MeshLab or Blender.
[Oliver] still has a lot of work to do on the model of his skull – cleaning up the meshes, removing his mandible, and possibly plugging the top of his spinal column if he would ever want to print a really, really awesome mug. All the data is there, though, ready for digital manipulation before sending it off to be printed.
Continue reading “Converting CTs And MRIs Into Printable Objects”