Working With Old High-Voltage EPROMs Is Fussy

EPROMs, those UV-erasable memory chips of the 80s and 90s, once played a crucial role in countless electronic devices. They’ve become relics of a bygone era, but for enthusiasts of vintage electronics, the allure of these light-sensitive devices remains strong. Today, we’re diving into [Kevin Osborn]’s nostalgic journey as he uncovers the secrets of old EPROMs loaded with Atari 7800 code.

[Kevin] used to work at General Computer Company, which produced the Atari 7800 and several games for the system. Thus, he had a handful of old carts and development EPROMs sitting up in his attic along with an old console. Recently, he decided to try and uncover what was on the EPROMs and begun an investigation. They wouldn’t run in his Atari, and he quickly realized why: the EPROMs weren’t cryptographically signed, so the system wouldn’t load them. Continue reading “Working With Old High-Voltage EPROMs Is Fussy”

Creating A 3D Visualization Of Freely Moving Organisms Using Camera Array And Software Algorithm

Observing a colony, swarm or similar grouping of creatures like ants or zebrafish over longer periods of time can be tricky. Simply recording their behavior with a camera misses a lot of information about the position of their body parts, while taking precise measurements using a laser-based system or LiDAR suffers from a reduction in parameters such as the resolution or the update speed. The ideal monitoring system would be able to record at high data rates and resolutions, while presenting the recorded data all three dimensions. This is where the work by Kevin C. Zhou and colleagues seeks to tick all the boxes, with a recent paper (preprint, open access) in Nature Photonics describing their 3D-RAPID system.

This system features a 9×6 camera grid, making for a total of 54 cameras which image the underlying surface. With 66% overlap between cameras across the horizontal dimension, there enough duplicate data between image stream that is subsequently used in the processing step to extract and reconstruct the 3D features, also helped by the pixel pitch of between 9.6 to 38.4 µm. The software is made available via the author’s GitHub.

Three configurations for the imaging are possible, ranging from no downsampling (1x) for 13,000×11,250 resolution at 15 FPS, to 2x downsampling (6,500×5,625@60FPS) and finally 4x (3,250×2,810@230FPS). Depending on whether the goal is to image finer features or rapid movement, this gives a range of options before the data is fed into the computational 3D reconstruction and stitching algorithm. This uses the overlap between the distinct frames to reconstruct the 3D image, which in this paper is used together with a convolutional neural network (CNN) to automatically determine for example how often the zebrafish are near the surface, as well as the behavior of fruit flies and harvester ants.

As noted in an interview with the authors, possible applications could be found in developmental biology as well as pharmaceutics.

Tiny Yet Functional Bike Built From Scratch

Sometimes, you just want to go ride your bike in the great outdoors, but you can’t be bothered throwing it in the back of the car. That wouldn’t be a problem if you rode this latest build from [The Q]: a bike small enough to fit in a handbag.

The build starts by customizing a rollerblade wheel to act as the driven rear wheel of the bike. It’s fitted with a tiny sprocket allowing it to be chain driven. Welding some steel tubes then nets a small diamond-layout bike frame. It’s fitted with a chain ring, pedals, and steering assembly just like a full-sized bike, just in absolute miniature.

Riding the bike is “uncomfortable,” in [The Q]’s own terms, but entirely possible. It basically requires the same level of contortion and technique as displayed by the clowns of your local circus. Don’t expect to use it as viable transportation, though. Walking would be much faster.

We’ve seen [The Q] build some wild bikes before, too, like this great hubless design. Video after the break.

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See Satellites In Broad Daylight With This Sky-Mapping Dish Antenna

If you look up at the night sky in a dark enough place, with enough patience you’re almost sure to see a satellite cross the sky. It’s pretty cool to think you’re watching light reflect off a hunk of metal zipping around the Earth fast enough to never hit it. Unfortunately, it doesn’t work during the daylight hours, and you really only get to see satellites in low orbits.

Thankfully, there’s a trick that allows you to see satellites any time of day, even the ones in geosynchronous orbits — you just need to look using microwaves. That’s what [Gabe] at [saveitforparts] did with a repurposed portable satellite dish, the kind that people who really don’t like being without their satellite TV programming when they’re away from home buy and quickly sell when they realize that toting a satellite dish around is both expensive and embarrassing. They can be had for a song, and contain pretty much everything needed for satellite comms in one package: a small dish on a motorized altazimuth mount, a low-noise block amplifier (LNB), and a single-board computer that exposes a Linux shell.

After figuring out how to command the dish to specific coordinates and read the signal strength of the received transponder signals, [Gabe] was able to cobble together a Python program to automate the task. The data from these sweeps of the sky resulted in heat maps that showed a clear arc of geosynchronous satellites across the southern sky. It’s quite similar to something that [Justin] from Thought Emporium did a while back, albeit in a much more compact and portable package. The video below has full details.

[Gabe] also tried turning the dish away from the satellites and seeing what his house looks like bathed in microwaves reflected from the satellite constellation, which worked surprisingly well — well enough that we’ll be trawling the secondary market for one of these dishes; they look like a ton of fun.

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Move Aside Yoda, It’s Furby’s Turn On Luke’s Back

When you want a backpack that turns heads and gets people talking, you can get ahead of the conversation with a talking backpack. [Nina] created a rucksack with the legendary babbler itself, the infamous Furby.

Believe it or not, no actual Furbies were sacrificed in the making of this backpack. The build uses an Arduino Nano, two servos, and a DFPlayer Mini for audio. A 3D printed faceplate is used for the iconic eyes and face. The code is fairly simple, waiting for a random delay and then triggering one of four effects. It can play a sound or blink and does its best to move the mouth while the sound is playing thanks to the handy busy line coming off the sound module. A unicorn children’s backpack offered a furry shell to stuff the electronics inside. A custom PCB makes the whole thing just a little neater internally.

Perhaps next [Nina] can integrate voice recognition so that the backpack can answer simple questions like an Alexa-powered Furby we’ve seen before.

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Why A Community Hackerspace Should Be A Vital Part Of Being An Engineering Student

Travelling the continent’s hackerspaces over the years, I have visited quite a few spaces located in university towns. They share a depressingly common theme, of a community hackerspace full of former students who are now technology professionals, sharing a city with a university anxious to own all the things in the technology space and actively sabotaging the things they don’t own. I’ve seen spaces made homeless by university expansion, I’ve seen universities purposefully align their own events to clash with a hackerspace open night and discourage students from joining, and in one particularly egregious instance, I’ve even seen a university take legal action against a space because they used the name of the city, also that of the university, in the name of their hackerspace. I will not mince my words here; while the former are sharp practices, the latter is truly disgusting behaviour.

The above is probably a natural extension of the relationship many universities have with their cities, which seems depressingly often to be one of othering and exclusion. Yet in the case of hackerspaces I can’t escape the conclusion that a huge opportunity is being missed for universities to connect engineering and other tech-inclined students with their alumni, enhance their real-world skills, and provide them with valuable connections to tech careers.

Yesterday I was at an event organised by my alma mater, part of a group of alumni talking to them about our careers.  At the event I was speaking alongside an array of people with varying careers probably more glittering than mine, but one thing that came through was that this was something of a rare opportunity for many of the students, to talk to someone outside the university bubble. Yet here were a group of engineers, many of whom had interesting careers based locally, and in cases were even actively hiring. If only there were a place where these two groups could informally meet and get to know each other, a community based on a shared interest in technology, perhaps?

It’s not as though universities haven’t tried on the hackerspace front, but I’m sad to say that when they fill a room with cool machines for the students they’re rather missing the point. In some of the cases I mentioned above the desire to own all the things with their own students-only hackerspace was the thing that led to the community hackerspaces being sabotaged. Attractive as they are, there’s an important ingredient missing, they come from a belief that a hackerspace is about its facilities rather than its community. If you were to look at a room full of brand-new machines and compare it with a similar room containing a temperamental Chinese laser cutter and a pair of battered 3D printers, but alongside a group of seasoned engineers in an informal setting, which would you consider to be of more benefit to a student engineer? It should not be a difficult conclusion to make.

Universities value their local tech industry, particularly that which has some connection to your university. You want your students to connect with your alumni, to connect with the local tech scene, and to ultimately find employment within it. At the same time though, you’re a university, you see yourselves as the thought leader, and you want to own all the things. My point is that these two positions are largely incompatible when it comes to connecting your engineering students with the community of engineers that surround you, and you’re failing your students in doing so.

Thus I have a radical proposal for universities. Instead of putting all your resources on a sterile room full of machines for your students, how about spending a little into placing them in a less shiny room full of professional engineers on their off-time? Your local hackerspace is no threat to you, instead it’s a priceless resource, so encourage your students to join it. Subsidise them if they can’t afford the monthly membership, the cost is peanuts compared to the benefit. Above all though, don’t try to own the hackerspace, or we’re back to the first paragraph. Just sometimes, good things can happen in a town without the university being involved.

Hackaday Podcast 212: Staring Through ICs, Reading Bloom Filters, And Repairing, Reworking, And Reballing

It was quite the cornucopia of goodness this week as Elliot and Dan sat down to hash over the week in hardware hacking. We started with the exciting news that the Hackaday Prize is back — already? — for the tenth year running! The first round, Re-Engineering Education, is underway now, and we’re already seeing some cool entries come in. The Prize was announced at Hackday Berlin, about which Elliot waxed a bit too. Speaking of wax, if you’re looking to waterproof your circuits, that’s just one of many coatings you might try. If you’re diagnosing a problem with a chip, a cheap camera can give your microscope IR vision. Then again, you might just use your Mark I peepers to decode a ROM. Is your FDM filament on the wrong spool? We’ve got an all-mechanical solution for that. We’ll talk about tools of the camera operator’s trade, the right to repair in Europe, Korean-style toasty toes, BGA basics, and learn just what the heck a bloom filter is — or is it a Bloom filter?

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download your own personal copy!

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