hardware

1719 Articles

Internals of the Blu-ray player, showing both the blu-ray drive and the custom PCBs

An Ingenious Blu-Ray Mini-Disk Player

June 1, 2024 by 13 Comments

[befi] brings us a project as impressive as it is reminiscent of older times, a Blu-Ray mini disk player. Easily fitting inside a pocket like a 8 cm CD player would, this is a labour of love and, thanks to [befi]’s skills both in electronics and in using a dremel tool.

A BluRay drive was taken apart, for a start, and a lot of case parts were cut off; somehow, [befi] made it fit within an exceptionally tiny footprint, getting new structural parts printed instead, to a new size. The space savings let him put a fully custom F1C100S-powered board with a number of unique features, from a USB-SATA chip to talk to the BluRay drive, to USB pathway control for making sure the player can do USB gadget mode when desired.

There’s an OLED screen on the side, buttons for controlling the playback, power and battery management – this player is built to a high standard, ready for day-to-day use as your companion, in the world where leaving your smartphone as uninvolved in your life as possible is a surprisingly wise decision. As a fun aside, did you know that while 8 cm CDs and DVDs existed, 8 cm BluRay drives never made it to market? If you’re wondering how is it that [befi] has disks to play in this device, yes, he’s used a dremel here too.

Everything is open-sourced – 3D print files, the F1C100S board, and the Buildroot distribution complete with all the custom software used. If you want to build such a player, and we wouldn’t be surprised if you were, there’s more than enough resources for you to go off. And, if you’re thinking of building something else in a similar way, the Buildroot image will be hugely helpful.

Want some entertainment instead? Watch the video embedded below, the build journey is full of things you never knew you wanted to learn. This player is definitely a shining star on the dark path that is Blu-Ray, given that our most popular articles on Blu-Ray are about its problems.

Continue reading “An Ingenious Blu-Ray Mini-Disk Player” →

An image of a grey plastic carrying case, approximately the size of an A5 notebook. Inside are darker grey felt lined cubbies with a mirror, piece of glass, a viewfinder, and various small printed parts to assemble a camera lucida.

Camera Lucida – Drawing Better Like It’s 1807

May 23, 2024 by 15 Comments

As the debate rages on about the value of AI-generated art, [Chris Borge] printed his own version of another technology that’s been the subject of debate about what constitutes real art. Meet the camera lucida.

Developed in the early part of the nineteenth century by [William Hyde Wollaston], the camera lucida is a seemingly simple device. Using a prism or a mirror and piece of glass, it allows a person to see the world overlaid onto their drawing surface. This moves details like proportions and shading directly to the paper instead of requiring an intermediary step in the artist’s memory. Of course, nothing is a substitute for practice and skill. [Professor Pablo Garcia] relates a story in the video about how [Henry Fox Talbot] was unsatisfied with his drawings made using the device, and how this experience was instrumental in his later photographic experiments.

[Borge]’s own contribution to the camera lucida is a portable version that you can print yourself and assemble for about $20. Featuring a snazzy case that holds all the components nice and snug on laser cut felt, he wanted a version that could go in the field and not require a table. The case also acts as a stand for the camera to sit at an appropriate height so he can sketch landscapes in his lap while out and about.

Interested in more drawing-related hacks? How about this sand drawing bot or some Truly Terrible Dimensioned Drawings?

Continue reading “Camera Lucida – Drawing Better Like It’s 1807” →

Mechanical 7-Segment Display Looks Clean

May 21, 2024 by 3 Comments

[Jens] wanted a subscriber counter for his YouTube channel. He could have gone with a simple OLED, LCD, or LED display, but he wanted something more tactile and interesting. So he built a mechanical 7-segment display instead!

Currently, [Jens]’s channel is in the four-digit subscriber range, so he planned to build a four-digit display. He started by searching for existing projects in this space, and came across the designs of [shiura] on Thingiverse. [shiura] had a 3D printed cam-driven 7-segment digit that runs on a single servo motor. Once armed with four of the digits, he hooked them up to a Pi Pico W to drive them all with four servo outputs. The Pico W is responsible for querying the channel subscriber count online, and updating the display in turn.

It’s a neat build, and [Jens] learned some things along the way—like how Super Lube seemed to ruin filament for him. Ultimately, the build came good, and it looks great. We’ve seen some other mechanical 7-segment builds before, too!

Continue reading “Mechanical 7-Segment Display Looks Clean” →

A thickness gauge, letter scale, push stick, and dial caliper

Measure Three Times, Design Once

May 16, 2024 by 35 Comments

Most of the Hackaday community would never wire a power supply to a circuit without knowing the expected voltage and the required current. But our mechanical design is often more bodged. We meet folks who carefully budget power to their microcontroller, sensors, and so on, but never measure the forces involved in their mechanical designs. Then they’re surprised when the motor they chose isn’t big enough for the weight of their robot.

An obstacle to being more numbers oriented is lack of basic data about the system. So, here are some simple tools for measuring dynamic properties of small mechanisms; distances, forces, velocities, accelerations, torques, and other things you haven’t thought about since college physics. If you don’t have these in your toolkit, how do you measure?

Continue reading “Measure Three Times, Design Once” →

The film scanner [xssfox] found, in the center of a table, with other stuff strewn across the table

Answering All Your ISCSI Scanner Questions

May 12, 2024 by 17 Comments

iSCSI is a widely used protocol for exposing SCSI devices over a network connection, and some scanners have in the past been equipped with SCSI ports. So, could you have an iSCSI network scanner? [xssfox] details her journey making a Canoscan FS4000US film scanner work over iSCSI, sparked by someone’s overly-confident StackOverflow comment that it couldn’t be done. Nothing in the spec said it couldn’t actually work, however, and after figuring out a tentative architecture, a hardware setup was put together.

No flatbed scanners with SCSI ports could be found on the cheap, so a film scanner had to be procured. After figuring out a few hitches with the loading mechanism and getting a test image locally, it was time to try and build up the software setup, tearing through SCSI compatibility and cabling, driver and PCI pass-through woes, bluescreens, and intermediate software having dropped some of the necessary features by now. Still, [xssfox] eventually exported the scanner as an iSCSI target – and, on the other end of the network, successfully connected to it and completed a scan. The StackOverflow answer was wrong, after all.

It’s fun to see how far old technology can go, and get answers to questions you never knew you had. Whether you’re reminiscing about SCSI days or wondering what the technology about, we’ve talked about it aplenty, from a retrospective to modern-day experiments, repurposing old SCSI hardware for modern SATA ports, a Raspberry Pi implementation, an emulator, and a fair bit more.

We thank [Valentijn Sessink] and [adistuder] for sharing this with us!

Ask Hackaday: Do You Calibrate Your Instruments?

May 9, 2024 by 54 Comments

Like many of you, I have a bench full of electronic instruments. The newest is my Rigol oscilloscope, only a few years old, while the oldest is probably my RF signal generator that dates from some time in the early 1950s. Some of those instruments have been with me for decades, and have been crucial in the gestation of countless projects.

If I follow the manufacturer’s recommendations then just like that PAT tester I should have them calibrated frequently. This process involves sending them off to a specialised lab where their readings are compared to a standard and they are adjusted accordingly, and when they return I know I can trust their readings. It’s important if you work in an industry where everything must be verified, for example I’m certain the folks down the road at Airbus use meticulously calibrated instruments when making assemblies for their aircraft, because there is no room for error in a safety critical application at 20000 feet.

But on my bench? Not so much, nobody is likely to face danger if my frequency counter has drifted by a few Hz. Continue reading “Ask Hackaday: Do You Calibrate Your Instruments?” →

A Brief History Of Keyboard Encoding

April 8, 2024 by 18 Comments
Photoelectric encoder keyboard configured as ASCII
Photoelectric encoder keyboard configured as ASCII

While typing away on our DIN, PS/2, USB or Bluetooth keyboards one of the questions which we rarely concern ourselves with is that of how the keyboard registers which keys we’re pressing. One exception here is when the keyboard can only register a limited number of simultaneous keypresses (rollover). Even though most keyboards today use a matrix which connects the keys, there are many configuration choices even here, which much like other keyboard configurations come with their own advantages and disadvantages. As a good primer we can look at this article by [Daniel Beardsmore] as he takes us through both historical and current-day keyboards.

Especially before  it was realistic to just put an entire microcontroller with a look-up table into every keyboard, more inventive approaches were required to not only register keypresses, but also encode them for the host computer. The photoelectric approach of the 1960s was one such encoding method, before diode matrices became popular, along with more exotic encoding switches that contained their code already hard-wired on their multitude of pins. One inevitable limitation with these was that of a lack of multi-key support, leading to the development of matrix scan technology around 1970.

Matrix scanning keyboards allow for multiple key presses at the same time, tackle debouncing of keys and were at the forefront of what gives us the ubiquitous and generally boringly reliable keyboards which we use today.