Day: July 25, 2022

The charging station on the table, with twelve powerbanks plugged into it, charging. A small meter on the front panel shows 4.73 volts and 4.38 amps.

A Simple Charging Station For Twelve Powerbanks

July 25, 2022 by 13 Comments

[jasonwinfieldnz] uses twelve small powerbanks day to day – powering LED strips around his trampoline, presumably, to avoid the mess of wires and make the assembly easily portable. However, if you have twelve powerbanks, you’ll find yourself hogging all the household’s microUSB cables every so often, as they eventually discharge. This was not good enough for our hacker, and he decided to build a charging station to refill them all at once.

If you need 5 volts and many amps, an ATX PSU isn’t your worst bet. From there, he only had to add twelve microUSB connectors to – and condensed the entire contraption into a beautiful charging station. For the microUSB part, he hacked some microUSB cable ends off and embedded them into the case. An embedded voltage and current module is of big help – letting you see at a glance when charging has really finished. Using copper tape as bus bars and banana plugs for charging input, this project is easy to build and solves the problem well.

The 3D printing files and cutting templates are right there on the project page, so if any of us hackers has a problem that twelve powerbanks could help with, [Jason]’s project is quite repeatable. If your devices are more diverse, you could use a pegboard to build a stylish charging station for them! If, on the other hand, you have a single device you need to plug multiple cords into, moldable plastic is there to help.

OpenJewelry, No Pliers Required

July 25, 2022 by 2 Comments

They say that if you want something done right, you gotta do it yourself. Oftentimes, that goes double for getting something done at all. Whereas some people might simply lament the lack of a (stable) Thingiverse-type site for, say, jewelry designs, those people aren’t Hackaday’s own [Adam Zeloof]. With nowhere to share designs among engineering-oriented friends, [Adam] took the initiative and created OpenJewelry, a site for posting open-source jewelry and wearable art designs as well as knowledge about techniques, materials, and processes.

[Adam] has seeded the site with a handful of his own beautiful designs, which run the gamut from traditional silversmithing techniques to 3D printing to fancy PCBs with working blinkenlights. You really should check it out, and definitely consider contributing.

Even if you don’t have any jewelry designs to share, the code is open as well, or you could even edit the wiki. Just be sure to read through the contribution guidelines first. If you don’t have the time for any of that, donations are welcome as well to help maintain the site.

We love wearable art around here, especially when it serves another purpose like this UV-sensing talisman, or this air quality necklace.

Up Close And Personal With An 8x Floppy Controller

July 25, 2022 by 44 Comments

In need of a floppy controller for a 286 he was working on, [Gadget Reboot] took to GitHub to see what was available in the open hardware space. There he found an ISA board capable of controlling up to eight drives from [Sergey Kiselev] called the Monster Floppy Disk Controller (FDC) — arguably overkill for the task, but too impressive to pass up. Luckily for us, he decided to document the build process in a video that covers everything from ordering the boards to configuring the BIOS.

Testing with four drives.

The video starts with a high-level overview of the schematic, which as you might have guessed, essentially puts two identical floppy controllers on the same board. You can tell this design was put together during the current chip shortage, as [Sergey] was careful to include some wiggle room if certain parts became unavailable and had to be swapped out for the alternatives listed in the BOM. It’s a decision that already paid off for [Gadget Reboot], as in some cases he had to go with the second-choice ICs.

[Gadget Reboot] was in for something of a surprise when he submitted the board for fabrication, as selecting the option for gold contacts on the edge connector made the production cost jump from $5 to nearly $300. He details how he was able to bring that cost back down a bit, but it still ended up being more than 10 times as expensive as the base price.

The second half of the video is dedicated to configuring the Monster FDC, which will certainly be a helpful resource for anyone looking to put this board to work in their own system. [Gadget Reboot] demonstrates using the board with “only” four floppy drives, and everything looks to work quite well.

Of course if your needs aren’t quite so grandiose, we’ve seen some more expedient floppy controllers which might be closer to what you’re looking for.

Continue reading “Up Close And Personal With An 8x Floppy Controller” →

McTerminals Give The Hamburglar A Chance

July 25, 2022 by 46 Comments

The golden arches of a McDonald’s restaurant are a ubiquitous feature of life in so many parts of the world, and while their food might not be to all tastes their comforting familiarity draws in many a weary traveler. There was a time when buying a burger meant a conversation with a spotty teen behind the till, but now the transaction is more likely to take place at a terminal with a large touch screen. These terminals have caught the attention of [Geoff Huntley], who has written about their surprising level of vulnerability.

When you’re ordering your Big Mac and fries, you’re in reality standing in front of a Windows PC, and repeated observation of start-up reveals that the ordering application runs under an administrator account. The machine has a card reader and a receipt printer, and it’s because of this printer that the vulnerability starts. In a high-traffic restaurant the paper rolls often run out, and the overworked staff often leave the cabinets unlocked to facilitate access. Thus an attacker need only gain access to the machine to reset it and they can be in front of a touch screen with administrator access during boot, and from that start they can do anything. Given that these machines handle thousands of card transactions daily, the prospect of a skimming attack becomes very real.

The fault here lies in whoever designed these machines for McDonalds, instead of putting appropriate security on the software the whole show relies on the security of the lock. We hope that they don’t come down on the kids changing the paper, and instead get their software fixed. Meanwhile this isn’t the first time we’ve peered into some McHardware.

A weighing scale with a moving-coil meter as a display

Hackaday Prize 2022: Arduino-Powered Weighing Scale Has A Real Analog Display

July 25, 2022 by 3 Comments

Digital displays are useful for quick and accurate readout, but lots of people prefer the physical motion of a needle moving along a dial. For instance, many smartwatch users choose an analog face to show the time, and modern cars with digital dashboards often default to showing an analog speedometer. Following this trend, [Miro Pavleski] built a digital weighing scale with an analog display that not only looks neat, but also serves as a good demonstration of the way that modern scales work.

Inside, the device is built up like a typical electronic scale: the heart of the instrument is a load cell that supports the platform and bends in proportion to the weight applied. This bending motion is sensed by a set of strain gauges wired up in a Wheatstone bridge configuration. An HX711 readout chip measures the resulting voltage and converts it to a digital code that is sent to a microcontroller, in this case an Arduino Nano.

Whereas a typical scale would then simply show the resulting number on an LCD display, [Mirko] decided to use a moving coil meter driven by the Arduino’s analog output. That meter was originally designed to show currents, so [Mirko] printed a new background image using kilograms instead.

Continue reading “Hackaday Prize 2022: Arduino-Powered Weighing Scale Has A Real Analog Display” →

2022 Hackaday Prize: Make Your World More Disaster Resistant, More Engaged

July 25, 2022 by 10 Comments

Following along with the 2022 Hackaday Prize theme on building a better world by doing what we all do best – hacking together solutions – the fourth round of the Prize focuses on making our local communities more resilient against and sensitive to severe weather and environmental disasters. Whether it’s an early warning system for wildfires or a distributed communication network that will keep working even when the cell phone service goes down, we’re challenging you to help make your world safer by reacting sooner and better. Get your project entered now!

Sensing

We love systems that help us monitor our environments, and not just for idle curiosity or citizen science. Sometimes it’s critical. We’ve seen monitors aimed at giving you a personal particulate air quality indicator, especially helpful for people with respiratory problems when downstream of a forest fire.

But even better is networking these together to generate an air quality map, or to log long-run trends over time and space. CanAirIO, for instance, has both a fixed and mobile unit that can help map out CO2 and particulate matter quality. Or maybe it’s not wildfires that invade your airspace, but rather pollution from car use. We’ve seen projects like that before too, and anything along these lines would make a great entry into this challenge round. Could you predict local air quality? Continue reading “2022 Hackaday Prize: Make Your World More Disaster Resistant, More Engaged” →

50-Year-Old 8-Track Changer Repair And Hack

July 25, 2022 by 28 Comments

For reasons still unclear, [Techmoan] has procured an RCA 8-track changer that holds five tape cartridges in a custom carrier. It somewhat works, but had a bit of mechanical issues here and there which needed some maintenance. Additionally, the player is designed for the US market and 60 Hz mains, but [Techmoan] is in the UK with 50 Hz.

Although electronics are used for the basic tape player portion, everything else is operated by mechanical gears, levers, and motors. The system plays both sides of each tape cartridge through to completion, and then switches automatically to the next one in the stack. Cartridges could be up to 90 minutes each, making for over seven hours of playing time. Oddly, the system does not repeat automatically after the fifth tape ends –operator intervention is required. It’s not entirely clear whether these carousels were primarily intended to play background music inside businesses, or built for niche consumer applications.

After discovering there was no setting to adjust the tape’s speed for 50/60 Hz operation, [Techmoan] could have ordered or fabricated a larger-diameter pulley for the motor drive shaft. But in true hacker style, he instead solves the problem with cellophane packing tape. By trial and error, he builds up the pulley diameter by winding lengths of tape until the music sounds just “good enough” to his ear. Then he pulls out the wow and flutter meter to really zero in — and gets it bang on. He says that this changer is needed for a future video, so we’re looking forward to see how it will be employed.

If you like these old mechanical logic controls, check out the video below the break. If you want dig into the workings of an 8-track player, check out Jenny List’s retro teardown from 2017.  Does anyone still use 8-track tapes any more?

Continue reading “50-Year-Old 8-Track Changer Repair And Hack” →