Open Source Scanner Scans The Slides

December 26, 2023 by 9 Comments

What do you get when you join a slide projector and a digital camera? Filmolimo, an open source slide scanner. The scanner uses an M5Stack Fire, an ESP32 development board. Thanks to the ESP32, you can control the device via WiFi.

All the project files, including KiCAD design files, are on GitHub. Of course, you will probably have to adapt things to your specific camera and slide projector. The PCB is double-sided and looks easy to put together. The board is mostly opto-isolation and interface between the controller and the equipment. The software allows you to change things like the time between slides, for example.

This is one of those projects you probably only need for a bit. Unless, of course, you regularly scan slides. You can farm it out to a service provider, but what fun is that? If you have a few hundred thousand slides, you might need to go for speed. If you just have a few, you can get by with a simple adapter.

ThunderScan: The Wild 1980s Product That Turned A Printer Into A Scanner

December 12, 2023 by 27 Comments

Back in the 1980s, printers were expensive things. Scanners were rare, particularly for the home market, because home computers could barely handle basic graphics anyway. Back in these halcyon days, an obscure company called Thunderware built a device to convert the former into the latter. It was known as the Thunderscan, and was a scanning head built for the Apple ImageWriter dot matrix printer. Weird enough already, but this device hides some weird secrets in its design.

The actual scanning method was simple enough; the device mounted a carriage to the printer head of the ImageWriter. In that carriage was an optical reflective sensor which was scanned across a page horizontally while it was fed through the printer. So far, so normal.

The hilarious part is how the scanner actually delivered data to the Macintosh computer it was hooked up to. It did precisely nothing with the serial data lines at all, these were left for the computer to command the printer. Instead, the output of the analog optical sensor was fed to a voltage-to-frequency converter, which was then hooked up to the handshake/clock-in pin on the serial port.

The scanner software simply looked at the rate at which new characters were becoming available on the serial port as the handshake pin was toggled at various frequencies by the output of the optical sensor. Faster toggling of the pin indicated a darker section of the image, slower corresponded to lighter.

Interestingly, [Andy Hertzfeld] also has his own stories to tell on the development, for which his software contribution seems to have netted him a great sum of royalties over the years. It’s funny to think how mainstream scanners once were; and yet we barely think about them today beyond a few niche uses. Times, they change.

Thanks to [J. Peterson] for the tip!

CT Scanner Reveals The Difference Between Real And Fake AirPods

November 29, 2023 by 20 Comments

These days, you have to be careful what you buy. Counterfeit hardware is everywhere, especially when you’re purchasing things sight unseen over the Internet. [Jon Bruner] recently set out to look at a bunch of fake AirPod clones, and found that the similarities between the imposters and the real thing are only skin deep. A CT scan reveals all.

As you might expect, Apple’s AirPods are a fine example of miniaturization. They’re packed to the gills with hardware, with very little wasted space inside. Flexible PCBs hook up the electronics in an elegant and tidy fashion. Three tiny MEMS microphones are on board to capture the user’s voice and filter out noise. The battery that runs the show is a hefty lithium-ion coin cell which fills almost all the empty space behind the audio driver.

By contrast, the fakes look positively weedy inside. They cut out the bonus microphones, using just one to do the job. Wires link up the different components, with unimpressive blobby soldering visible that has splattered around the internal enclosure. Even the cases are lower-tech, with a weaker battery and a poorer charging solution. Hilariously, cheaping out on the tech makes the fakes lighter, so they compensate by adding weights to create a sense of heft for the user.

It’s amazing how much is revealed by a CT scan, that doesn’t even require opening the devices to tear them down. Fake hardware really is a scourge that many in the tech industry find themselves fighting against on a regular basis.

LiPo Replacement Keeps Portable Scanner In The Action

November 21, 2023 by 8 Comments

If there’s anything people hate more than being locked into a printer manufacturer’s replacement cartridges, it’s proprietary batteries. Cordless power tools are the obvious example in this space, but there are other devices that insist on crappy battery packs that are expensive to replace when they eventually die.

One such device is the Uniden Bearcat BC296D portable scanner that [Robert Guildig] found for a song at a thrift store, which he recently gave a custom LiPo battery upgrade. It came equipped with a nickel-cadmium battery pack, which even under the best of circumstances has a very limited battery life. Using regular AA batteries wasn’t an option, but luckily the space vacated by the OEM battery pack left a lot of room for mods. Those include a small module with BMS functions and a DC-DC converter, a 2,400 mAh 4.2 V LiPo pillow pack, and a new barrel connector for charging. With the BMS set for six volts and connected right to the old battery pack socket, the scanner can now run for seven hours on a one-hour charge. As a bonus, the LiPo pack should last a few times longer than the NiCd packs, and be pretty cheap to replace when it finally goes too. There’s a video after the hop with all the details.

If you’re looking at a similar battery replacement project, you might want to check out [Arya]’s guide to everything you need to know about lithium-ion circuitry.

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This 3D Scanner Uses A Sensor You Might Not Know About

August 14, 2023 by 24 Comments

The huge diversity of sensors and other hardware which our community now has access to seems comprehensive, but there remain many parts which have made little impact due to cost or scarcity. It’s one of these which [Enginoor] has taken for the sensor in a 3D scanner, an industrial laser displacement sensor.

This sensor measures distance, but it’s not one of the time-of-flight sensors we’re familiar with. Instead it’s similar to a photographic rangefinder, relying on the parallax angle as seen from a sensor a distance apart from the laser. They are extremely expensive due to their high-precision construction, but happily they can be found at a more affordable level second-hand from decommissioned machinery.

In this case the sensor is mounted on an X-Y gantry, and scans the part making individual point measurements. The sensor is interfaced to a Teensy, which in turn spits the data back to a PC for processing. By their own admission it’s not the most practical of builds, but for us that’s not the point. We hope that bringing these parts to the attention of our community might see them used in other ways.

We’ve featured huge numbers of 3D scanners over the years, including a look at how not to make one.

Secret Bookshelf Door Uses Hidden Fingerprint Scanner

May 30, 2023 by 4 Comments

What is it that compels us about a secret door? It’s almost as if the door itself and the promise of mystery is more exciting than whatever could lay beyond. In any case, [Scott Monaghan] is a lover of the form, and built his own secret door hidden in a bookshelf, as all good secret doors should be.

The door is activated by pulling down on the correct book. This then reveals a fingerprint scanner. Upon presenting the right digit, the door will elegantly swing open to reveal the room beyond. Secret door experts will note there’s an obvious tell due to the light spilling through the cracks, however [Scott] reports that the finishing stages of the build solved this issue. The door was also fitted with a manual release for easier daily use.

Details are light, but the basics are all there. Really all you need is a cheap hardware store door opener, a secret activation lever or authentication method, and a well-hinged bookcase to achieve this feat yourself. We’ve seen some other great secret doors before, too. Video after the break.

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Laser Scanner Upgraded To Use PCB Motor

February 22, 2023 by 10 Comments

[Rik]’s Hexastorm laser scanner project originally used a discrete polygon mirror controller+motor module from Sharp to spin a prism. But the scanner head was a bit difficult to assemble and had a lot of messy wires. This has all been replaced by a single board featuring a PCB-printed motor, based on the work of [Carl Bugeja]. The results are promising so far — see video below the break.

Since the prism is not attached to anything, currently it will fall off if mounted in the intended vertical orientation. One of [Rik]’s next steps is to improve the mount’s design to constrain the spinning prism. The previous Sharp motor was specified to 21000 RPM, but was only driven to 2400 RPM in [Rik]’s first version. This new PCB motor spins at 2000 RPM in these tests, comparable to his previous experiments ( we’re not sure about the maximum RPM ).

See our original writeup from 2019 to review the goals of this project, and be sure to checkout details and documentation on the Hexastorm project page. To learn more about PCB motors, read our article about [Carl]’s first design and visit his Hackaday.io page. Thanks to [Jonathan Beri] for the tip.

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