Living The Dream: New PCB For A Dirt-Cheap Calculator Watch

Well, this hack has us tickled pink. We love the idea of buying some really cheap piece of technology and doing something amazing with it, and this is a textbook example of that. [davedarko] found the cutest little calculator watch on Ali Express and is working on making a new PCB for it. The plan is to use an ARM processor and Arduino and add a few extras like 24-hour mode and a pink (or potentially RGB) backlight. The new brain will be an ATSAML22G18A, which has an on-board LCD controller and exactly one I/O pin to spare without charlieplexing the buttons.

One of [davedarko]’s primary goals is to keep the LCD and figure out how to talk to it. The first order of business was reverse engineering the watch’s LCD controller by sussing out the secrets from beneath the black blob of epoxy. This was an eye-opening experience as [davedarko] had never worked directly with LCDs before. A strange reading made him bust out the oscilloscope. Long-ish and informative story short, [davedarko] found out that it uses a bias of 1/2 for generating the wave necessary to multiplex the segments and keep the signal alternating. This is definitely one to watch!

We love timepieces around here and have seen all kinds of hacks, especially on Casio watches. Want dark mode? Done. Enable the hidden countdown timer? We’ve got that, too. And have you ever wondered just how water-resistant the F91W is?

Step ‘n Snack Fanny Pack Motivates With M&Ms

[Sam March] has made a lot of different kinds of things, many of which have appeared on these very pages. Nowadays he wants to get the viewers more involved in his projects, so he started doing a monthly collaboration with YT viewers. Basically, he gives a prompt, and people comment with their wild and crazy ideas on the topic. Whoever has the winning idea gets the finished build. The maiden prompt was ‘fanny pack’, and you can check out the result in the build video (embedded below).

Someone suggested a Reese’s cup-dispensing fanny pack that gives you one cup for every 10,000 steps you take. We like what [Sam] did with that idea, because it’s way more practical — M&Ms are the original travel candy, and this way, you get to eat chocolate way more often. Depending on your sweet tooth, Reese’s Pieces would be a good compromise.

[Sam] figured out that the average human burns one calorie for every 25 steps, and that the average plain M&M is worth four calories, so he built a fanny pack with a step counter that dispenses one M&M for every 100 steps taken using a tiny auger. It’s calorie-neutrality!

You might be wondering if [Sam] made the fanny pack, too, or used something store-bought. The answer is neither: at some point in the build process, a company graciously offered to make a fanny pack with a special compartment in the bottom for the M&M dispenser. If you want to build one of these for yourself, you can get the CAD file for the milled base, the screw, the hopper, and the lid plus the code and also the gerbers on GitHub. We see a place for the sewing pattern, but as of now, the folder is empty. Be sure to check out the build and demo video after the break as [Sam] hits the town in a screaming set of neon workout wear to test the dispenser.

Most of the M&M-based projects we see around here are designed to sort by color. Here’s one that searches for the holy grail — peanut M&Ms that didn’t get a peanut. Continue reading “Step ‘n Snack Fanny Pack Motivates With M&Ms”

3D-Printed Tooling Enables DIY Electrochemical Machining

When it comes to turning a raw block of metal into a useful part, most processes are pretty dramatic. Sharp and tough tools are slammed into raw stock to remove tiny bits at a time, releasing the part trapped within. It doesn’t always have to be quite so violent though, as these experiments in electrochemical machining suggest.

Electrochemical machining, or ECM, is not to be confused with electrical discharge machining, or EDM. While similar, ECM is a much tamer process. Where EDM relies on a powerful electric arc between the tool and the work to erode material in a dielectric fluid, ECM is much more like electrolysis in reverse. In ECM, a workpiece and custom tool are placed in an electrolyte bath and wired to a power source; the workpiece is the anode while the tool is the cathode, and the flow of charged electrolyte through the tool ionizes the workpiece, slowly eroding it.

The trick — and expense — of ECM is generally in making the tooling, which can be extremely complicated. For his experiments, [Amos] took the shortcut of 3D-printing his tool — he chose [Suzanne] the Blender monkey — and then copper plating it, to make it conductive. Attached to the remains of a RepRap for Z-axis control and kitted out with tanks and pumps to keep the electrolyte flowing, the rig worked surprisingly well, leaving a recognizably simian faceprint on a block of steel.

[Amos] admits the setup is far from optimized; the loop controlling the distance between workpiece and tool isn’t closed yet, for instance. Still, for initial experiments, the results are very encouraging, and we like the idea of 3D-printing tools for this process. Given his previous success straightening his own teeth or 3D-printing glass, we expect he’ll get this fully sorted soon enough.

Scanning Medium Format Film On A 35mm Scanner

Scanning film is great for archival purposes as well as sharing said photos digitally. However, if you’re scanning 120 film, aka medium format, it can be expensive to get the requisite hardware. 35mm scanners are comparatively more common, so [Christian Chapman] decided to modify one to suit medium film instead.

The hack is for the Plustek 8100, and requires modifying the scanner in two ways. Firstly, the driver has to be scanned to sweep a longer range to take into account the bigger film. Secondly, a part of the film carriage has to be replaced so it doesn’t show up in the scanners field of view.

The former is achieved by using the sane-genesys scanner software backend, which can be easily modified to adjust the scan length values appropriately. The latter is achieved via 3D printing replacement components that fit without blocking the requisite area.

It’s a tidy hack and one that allows [Christian] to both scan medium format film as well as overscan 35mm film to capture details from the sprocket hole area. We’ve seen fully custom film scanner builds before, too. If you’ve built your own scanner, be sure to drop us a line!

Emulating The IBM PC On An ESP32

The IBM PC spawned the basic architecture that grew into the dominant Wintel platform we know today. Once heavy, cumbersome and power thirsty, it’s a machine that you can now emulate on a single board with a cheap commodity microcontroller. That’s thanks to work from [Fabrizio Di Vittorio], who has shared a how-to on Youtube. 

The full playlist is quite something to watch, showing off a huge number of old-school PC applications and games running on the platform. There’s QBASIC, FreeDOS, Windows 3.0, and yes, of course, Flight Simulator. The latter game was actually considered somewhat of a de facto standard for PC compatibility in the 1980s, so the fact that the ESP32 can run it with [Fabrizio’s] code suggests he’s done well.

It’s amazingly complete, with the ESP32 handling everything from audio and video to sound output and keyboard and mouse inputs. It’s a testament to the capability of modern microcontrollers that this is such a simple feat in 2021.

We’ve seen the ESP32 emulate 8-bit gaming systems before, too. If you remember [Fabrizio’s] name, it’s probably from his excellent FabGL library. Videos after the break. Continue reading “Emulating The IBM PC On An ESP32”

Rooting The Atari VCS 800

The Atari VCS 800 is a modern product, a hybrid of a PC and a games console. Fundamentally, its a bunch of modern chips in a box running Linux that will let you browse the web or emulate some old games. Now, thanks to [ArcadeHustle], you can have persistent root access to the VCS 800 at your leisure.

The trick is simple, and begins by interrupting the systemd startup scripts on boot. One can then merge files into the /etc directory to achieve root access, either by the tty terminal or over TCP. It’s all wrapped up in the script available at the Github link above.

You can actually run a variety of OSs on the hardware, as it’s powered by an AMD Ryzen R1606G CPU and runs straightforward PC architecture. However, if you want to customize the existing OS to do your bidding, this hack is the way to go.

Hacking to get root access is key if you want to get anywhere with a system. We’ve seen it done on thin clients as well as car infotainment systems to give the owner full control over the hardware they own. If you’ve got your own root exploit you’d like to share, do drop us a line, won’t you?

 

Black And White TV Was Hiding A Special Input Board

[John Floren] found a nice old black & white TV in a thrift store, and as so many of us would, he decided to take it home. He was surprised upon getting it there that it had, in addition to the VHF and UHF antenna inputs, a mysterious extra connector on the back. Naturally, he set about investigating.

On the rear was an obviously hacked-in F-type connector, paired with a toggle switch, both unlabelled. Running the output of an RF modulator to the connector didn’t net an image on the screen, even though the same method worked when hooked up to the antenna inputs. Undeterred, [John] dug deeper.

Inside, a little PCB bearing the mark “TVM.04” was inside, bearing a handful of components. The device turned out to be a Pickes and Trout TVM-04 adapter, designed in the 1970s for hooking a computer up to a television for use as a monitor. The adapter board allows the Hitachi TV to accept a composite video input. [John] was able to test the TV with a NES clone outputting composite video and voila, it worked! [John] then went further, adding an audio input and installing standard RCA jacks to make it easier to use the input with more modern electronics.

It’s a great example of how simply opening up some electronics and poking around can teach you something. Hacking on old-school TVs is a popular pastime around these parts, it seems. If you’ve been working on your own retro display hack, be sure to let us know.