MoreRSS

site iconHackadayModify

Hackaday serves up Fresh Hacks Every Day from around the Internet. Our playful posts are the gold-standard in entertainment for engineers and engineering enthusiasts.
Please copy the RSS to your reader, or quickly subscribe to:

Inoreader Feedly Follow Feedbin Local Reader

Rss preview of Blog of Hackaday

What Isaac Roberts Saw Without a Space Telescope

2026-01-21 02:00:04

Space telescopes are all the rage, and rightfully so. The images they take are spectacular, and they’ve greatly increased what we know about the universe. Surely, any picture taken of, say, the Andromeda galaxy before space telescopes would be little more than a smudge compared to modern photos, right? Maybe not.

One of the most famous pictures of our galactic neighbor was taken in — no kidding — 1888. The astronomer/photographer was Isaac Roberts, a Welsh engineer with a keen interest in astrophotography. Around 1878, he began using a 180 mm refracting telescope for observations, and in 1883, he began taking photographs.

He was so pleased with the results that he ordered a reflecting telescope with a 510 mm first-surface mirror and built an observatory around it in 1885. Photography and optics back then weren’t what they are now, so adding more mirrors to the setup made it more challenging to take pictures. Roberts instead mounted the photographic plates directly at the prime focus of the mirror.

Andromeda

This image, captured with the NASA/ESA Hubble Space Telescope, is the largest and sharpest image ever taken of the Andromeda galaxy — otherwise known as M31. This is a cropped version of the full image and has 1.5 billion pixels. You would need more than 600 HD television screens to display the whole image. It is the biggest Hubble image ever released and shows over 100 million stars and thousands of star clusters embedded in a section of the galaxy’s pancake-shaped disc stretching across over 40 000 light-years. This image is too large to be easily displayed at full resolution.

Because it took hours to capture good images, he developed techniques to keep the camera moving in sync with the telescope to track objects in the night sky. On December 29th, 1888 he used his 510 mm scope to take a long exposure of Andromeda (or M31, if you prefer). His photos showed the galaxy had a spiral structure, which was news in 1888.

Of course, it’s not as good as the Hubble’s shots. In all fairness, though, the Hubble’s is hard to appreciate without the interactive zoom tool. And 100 years of technological progress separate the two.

Roberts also invented a machine that could engrave stellar positions on copper plates. The Science Museum in London has the telescope in its collection.

Your Turn

Roberts did a great job with very modest equipment. These days, at least half of astrophotography is in post-processing, which you can learn. Want time on a big telescope? Consider taking an online class. You might not match the James Webb or the Hubble, but neither did Roberts, yet we still look at his plates with admiration.

Demonstrating The Sheer Lack Of Security In First Gen Cellular Networks

2026-01-21 00:30:10

Modern cellular networks are built to serve millions upon millions of users, all while maintaining strict encryption across all communications. But earlier cellular networks were by no means so secure, as [Nostalgia for Simplicity] demonstrates in a recent video.

The video begins with an anecdote — our narrator remembers a family member who could listen in on other’s conversations on the analog AMPS phone network. This was easily achieved simply by entering a code that would put an Ericsson handset into a test mode, in which it could be switched to tune in any desired AMPS channel. Since the communications were transmitted in a purely analog manner, with no encryption of any sort, any conversation on such a network was basically entirely open for anyone to hear. The video shows a recreation of this method, using a software-defined radio to spin up a low-power, very local AMPS network. A phone call is carried out between two handsets, with a third handset able to listen in just by using the special test mode.

If you’re particularly keen to build your own first-generation AMPS phone network, just know that it’s not really allowed due to rules around spectrum allocations. Still, it’s entirely possible as we’ve covered before. It doesn’t even take much hardware in our modern SDR era.

Marion Stokes Fought Disinformation with VCRs

2026-01-20 23:00:16

You’ve likely at least heard of Marion Stokes, the woman who constantly recorded television for over 30 years. She comes up on reddit and other places every so often as a hero archivist who fought against disinformation and disappearing history. But who was Marion Stokes, and why did she undertake this project? And more importantly, what happened to all of those tapes? Let’s take a look.

Marion the Librarian

Marion was born November 25, 1929 in Germantown, Philadelphia, Pennsylvania. Noted for her left-wing beliefs as a young woman, she became quite politically active, and was even courted by the Communist Party USA to potentially become a leader. Marion was also involved in the civil rights movement.

Marion Stokes on the set of her public access television show, Input.
Marion on her public-access program Input. Image via DC Video

For nearly 20 years, Marion worked as a librarian at the Free Library of Philadelphia until she was fired in the 1960s, which was likely a direct result of her political life. She married Melvin Metelits, a teacher and member of the Communist Party, and had a son named Michael with him.

Throughout this time, Marion was spied on by the FBI, to the point that she and her husband attempted to defect to Cuba. They were unsuccessful in securing Cuban visas, and separated in the mid-1960s when Michael was four.

Marion began co-producing a Sunday morning public-access talk show in Philadelphia called Input with her future husband John Stokes, Jr. The focus of the show was on social justice, and the point of the show was to get different types of people together to discuss things peaceably.

Outings Under Six Hours

Marion’s taping began in 1979 with the Iranian Hostage Crisis, which coincided with the dawn of the twenty-four-hour news cycle. Her final tape is from December 14, 2012 — she recorded coverage of the Sandy Hook massacre as she passed away.

In 35 years of taping, Marion amassed 70,000 VHS and Beta-max tapes. She mostly taped various news outlets, fearing that the information would disappear forever. Her time in the television industry taught her that networks typically considered preservation too expensive, and therefore often reused tapes.

But Marion didn’t just tape the news. She also taped various programs such as The Cosby Show, Divorce Court, Nightline, Star Trek, The Oprah Winfrey Show, and The Today Show. Some of her collection includes 24/7 coverage of news networks, all of which was recorded on up to eight VCRs: 3-5 were going all day every day, and up to 8 would be taping if something special was happening. All family outings were planned around the six-hour VHS tape, and Marion would sometimes cut dinner short to go home and change the tapes.

People can’t take knowledge from you.  — Marion Stokes

You might be wondering where she kept all the tapes, or how she could afford to do this, both financially and time-wise. For one thing, her second husband John Stokes, Jr. was already well off. For another, she was an early investor in Apple stock, using capital from her in-laws. To say she bought a lot of Macs is an understatement. According to the excellent documentary Recorder, Marion own multiples of every Apple product ever produced. Marion was a huge fan of technology and viewed it as a way of unlocking people’s potential. By the end of her life, she had nine apartments filled with books, newspapers, furniture, and multiples of any item she ever became obsessed with.

In addition to the creating this vast video archive, Marion took half a dozen daily newspapers and over 100 monthly periodicals, which she collected for 50 years. This is not to mention the 40-50,000 books in her possession. In one interview, Marion’s first husband Melvin Metelits has said that in the mid-1970s, the family would go to a bookstore and drop $800 on new books. That’s nearly $5,000 in today’s money.

Why Tapes? Why Anything?

It’s easy to understand why she started with VHS tapes — it was the late 1970s, and they were still the best option. When TiVo came along, Marion was not impressed, preferring not to expose her recording habits to any possible governments. And she had every right to be afraid, with her past.

Those in power are able to write their own history.  — Marion Stokes

As for the why, there were several reasons. It was a form of activism, which partially defined Marion’s life. The rest I would argue was defined by this archive she amassed.

Marion started taping when the Iranian Hostage Crisis began. Shortly thereafter, the 24/7 news cycle was born, and networks reached into small towns in order to fill space. And that’s what she was concerned with — the effect that filling space would have on the average viewer.

Marion was obsessed with the way that media reflects society back upon itself. With regard to the hostage crisis, her goal was trying to reveal a set of agendas on the part of governments. Her first husband Melvin Metelits said that Marion was extremely fearful that America would replicate Nazi Germany.

The show Nightline was born from nightly coverage of the crisis. It aired at 11:30PM, which meant it had to compete with the late-night talk show hosts. And it did just fine, rising on the wings of the evening soap opera it was creating.

To the Internet Archive

When Marion passed on December 14, 2012, news of the Sandy Hook massacre began to unfold. It was only after she took her last breath that her VCRs were switched off. Marion bequeathed the archive to her son Michael, who spent a year and half dealing with her things. He gave her books to a charity that teaches at-risk youth using secondhand materials, and he says he got rid of all the remaining Apples.

A screen capture of the Marion Stokes video collection on the Internet Archive.
Image via The Internet Archive

But no one would take the tapes. That is, until the Internet Archive heard about them. The tapes were hauled from Philadelphia to San Francisco, packed in banker’s boxes and stacked in four shipping containers.

So that’s 70,000 tapes at let’s assume six hours per tape, which totals 420,000 hours. No wonder the Internet Archive wasn’t finished digitizing the footage as of October 2025. That, and a lack of funding for the massive amount of manpower this must require.

If you want to see what they’ve uploaded so far, it’s definitely worth a look. And as long as you’re taking my advice, go watch the excellent documentary Recorder on YouTube. Check out the trailer embedded below.

Main and thumbnail images via All That’s Interesting

Inside Air Traffic Control

2026-01-20 20:00:44

It is a movie staple to see an overworked air traffic controller sweating over a radar display. Depending on the movie, they might realize they’ve picked the wrong week to stop some bad habit. But how does the system really work? [J. B. Crawford] has a meticulously detailed post about the origins of the computerized air traffic control system (building on an earlier post which is also interesting).

Like many early computer systems, the FAA started out with the Air Force SAGE defense system. It makes sense. SAGE had to identify and track radar targets. The 1959 SATIN (SAGE Air Traffic Integration) program was the result. Meanwhile, different parts of the air traffic system were installing computers piecemeal.

SAGE and its successors had many parents: MIT, MITRE, RAND, and IBM. When it was time to put together a single national air traffic system the FAA went straight to IBM, who glued together a handful of System 360 computers to form the IBM 9020. The computers had a common memory bus and formed redundant sets of computer elements to process the tremendous amount of data fed to the system. The shared memory devices were practically computers in their own right. Each main computing element had a private area of memory but could also allocate in the large shared pool.

The 9200 ran the skies for quite a while until IBM replaced it with the IBM 3083. The software was mostly the same, as were the display units. But the computer hardware, unsurprisingly, received many updates.

If you’re thinking that there’s no need to read the original post now that you’ve got the highlights from us, we’d urge you to click the link anyway. The post has a tremendous amount of detail and research. We’ve only scratched the surface.

There were earlier control systems, some with groovy light pens. These days, the control tower might be in the cloud.

DIY Magnetic Markers Help 3D Scan Tricky Objects

2026-01-20 17:00:42

3D scanners rely on being able to identify physical features of an object, and line up what it saw a moment ago with what it sees now in order to build a 3D model. However, not every object is as distinct and visible as others at all angles, particularly in IR. One solution is reflective scanning markers, which are either pre-printed on a mat, or available as stickers that can be applied to objects to give the scanner a bit more to latch onto, visually speaking.

[firstgizmo] shows a slightly different approach: that of surrounding the object to be scanned with 3D printed reflective markers instead of covering the target object itself with reflectors, or relying on a flat scanning mat.

Magnetic mounts allow mixing and matching, as well as attaching directly to some objects to be scanned.

The main advantage (besides not having to remove stickers from the object afterwards) is that these printed markers present the reflective dots at a variety of angles during the scanning process. This makes the scene less sensitive to scanner angle in general, which is good because the angle at which to scan an important feature of an object is not always the angle that responds best.

By giving the scene more structure, the scanner can have a better shot at scanning reliably even if the reflectors aren’t on the target object itself. It also helps by making it easier to combine multiple scans. The more physical features scans have in common, the easier it is to align them.

Just to be clear, using these means one will, in effect, be 3D scanning the markers along with the target object. But once all the post-processing is done, one simply edits the model to remove everything except the target object.

[firstgizmo]’s DIY magnetic 3D scanning markers are an expanded take on an idea first presented by [Payo], who demonstrates the whole concept wonderfully in the video below.

3D scanning can be tremendously handy but it does have its quirks and limitations, and a tool like this can be the difference between a terrible scan and a serviceable one. For a quick catch-up on 3D scanning and its strengths and limitations, read our hands-on tour of using an all-in-one 3D scanner.

BASIC on a Calculator Again

2026-01-20 14:00:30

We are always amused that we can run emulations or virtual copies of yesterday’s computers on our modern computers. In fact, there is so much power at your command now that you can run, say, a DOS emulator on a Windows virtual machine under Linux, even though the resulting DOS prompt would probably still perform better than an old 4.77 MHz PC. Remember when you could get calculators that ran BASIC? Well, [Calculator Clique] shows off BASIC running on a decidedly modern HP Prime calculator. The trick? It’s running under Python. Check it out in the video below.

Think about it. The HP Prime has an ARM processor inside. In addition to its normal programming system, it has Micropython as an option. So that’s one interpreter. Then PyBasic has a nice classic Basic interpreter that runs on Python. We’ve even ported it to one or two of the Hackaday Superconference badges.

If you have a Prime, this is a great way to make it even easier to belt out a simple algorithm. Of course, depending on your age, you might prefer to stick with Python. Fair enough, but don’t forget the many classic games available for Basic. Adventure and Hunt the Wumpus are two of the sample programs included.