Taking A Walk Down [Computer] Memory Lane

August 9, 2021 by Ryan Flowers 15 Comments

There’s nothing quite like going to a museum and being given a tour by a docent who really knows their way around the exhibits. When that docent has first hand experience in the subject matter, the experience is enhanced even further. So you can imagine our excitement when hacker, maker, and former DEC mainframe memory engineer [Ned Utzig] published a tour of what he calls “Memories of Weird Memories of Computers Past.” [Ned] expertly guides us through each technology, adding flavor and nuance to an already fascinating subject.

The tour begins with early storage media such as IBM punch cards, and then walks us through time to the paper tape, vacuum tubes, and even complex vats of mercury — all used for the sake of storing data either permanently or temporarily.

Next in the exhibit is an impressive CRT hack that isn’t unlike modern DRAM. The tour continues on to ferrite core memory such as that used on mainframes, minicomputers, and even the Apollo Guidance Computer. Each type is examined for its strengths and weaknesses and its place in computing history.

We really appreciated the imaginative question posed toward the end of the article. We won’t give it away here- it’s worth it to go give The Mad Ned Memo a read.

Is obsolete technology your cup of tea? Perhaps an Arduino based experiment with core memory will scratch the itch, or maybe storing data in thin air will bring back memories of computers gone by.

Animation In Education, 1950’s Style

August 9, 2021 by Chris Lott 8 Comments

Back before the days of computers, animation was drawn by hand. We typically think of cartoons and animated feature films, but there were other genres as well. For example, animation was also used in educational and training films. [Javier Anderson] has tracked down a series of antenna and RF training videos from the Royal Canadian Air Force in the 1950s and 60s and posted them on his YouTube channel.

He has found three of these gems, all on the topic of antenna fundamentals: propagation, directivity, and bandwidth (the film on propagation is linked below the break). Casually searching for the names listed in the film’s credits will lead you down an endless and fascinating rabbit hole about the history of Canadian animation and the formation of the Canadian National Film Board and its Studio A group of pioneering young artists (one can easily lose a couple of hours doing said searches, so be forewarned). For these films that [Javier] located, the animator is [Kaj Pindal]. [Kaj] (1927-2019) was a Dane who learned his craft as a teenager, drawing underground anti-Hitler comics in Copenhagen until fleeing for his life. He later emigrated to Canada, where he had a successful career as an artist and educator.

Animator [Kaj Pindal] at his desk, c.2012

Anyone who has tried to really grasp the physical connection between currents flowing in an antenna wire and the resultant radiated signal described by the second-order partial differential electromagnetic wave equation, all while using only a textbook, will certainly agree — unarguably this is a topic whose teaching can be significantly improved by animations such as [Kaj]’s. And if you’d like to sprinkle more phrases like “… in time-phase and space-quadrature …” into your conversations, then this film series is definitely for you.

Have you encountered any particularly helpful or well-made animated educational videos in your education and/or career? Are there any examples of similar but modern films made using computer generated images? Thanks to reader [Michael Murillo] for tipping us off to these old films.

Continue reading “Animation In Education, 1950’s Style” →

Relay Logic Nixie Tube Clock Checks All The Boxes

August 9, 2021 by Ryan Flowers 5 Comments

There are a few words in the electrical engineering lexicon that will perk any hardware hacker’s ears. The first of course is “Nixie tubes” with their warm cold war era ambiance and nostalgia inducing aura. A close second is “relay logic”. Between their place in computing and telecom history and the way a symphony of click and clatter can make a geek’s heart go pitter patter, most of us just love a good relay hack. And then there’s the classic hacker project: A unique timepiece to adorn our lair and remind us when we’ve been working on our project just a little too long, if such a thing even exists.

With those things in mind, you can forgive us if we swooned ever so slightly when [Jon Stanley]’s Relay Logic Nixie Tube Clock came to us via the Tip Line. Adorned with its plethora of clicking relays and set aglow by four Nixie tubes, the Relay Logic Nixie Tube Clock checks all our boxes.

[Jon] started the build with relay modules that mimic CD4000 series CMOS logic chips. When the prototype stage was complete, the circuit was recreated on a new board that mounts all 55 Omron relays on the same PCB. The result? A glorious Nixie tube clock that will strike envy into even the purest hacker’s heart. Make sure to watch the video after the break!

[Jon] has graciously documented the entire build and even makes various relay logic boards available for purchase if you’d like to embark on your own relay logic exploits . His site overflows with unique clock projects as well, so you can be sure we’ll be checking those out.

If you feel inspired to build your own relay logic project, make sure you source genuine Omron relays, especially if your Relay Computer Masterpiece takes six years to build.

Thanks to [Daniel] for sending this our way. Got a cool project you’d like to share? Be sure to send it in via the Tip Line.

Continue reading “Relay Logic Nixie Tube Clock Checks All The Boxes” →

Improving OLED VU Meters With A Little Physics

August 9, 2021 by Tom Nardi 23 Comments

Last month we featured a project that aimed to recreate the iconic mechanical VU meter with an Arduino and a common OLED display. It was cheap and easy to implement, and promised to bring a little retro style to your otherwise thoroughly modern project.

[sjm4306] liked the idea, but thought it was a tad too stiff. So he’s been experimenting with adding some physics to the meter’s virtual needle to better approximate the distinctive lag and overshoot that’s part and parcel of analog indicators. Obviously it’s something that can only be appreciated in motion, so check out the video below for an up-close look at his quasi-retro indicator.

Unfortunately there’s no code for you to play with right now, but [sjm4306] says he’ll release it on the project’s Hackaday.IO page once he’s cleaned things up a bit. We know it will take more than a few wiggling pixels to pry real analog indicators out of some hacker’s tool boxes, but anything that helps improve the digital approximation of this sort of vintage hardware is a win in our book. Continue reading “Improving OLED VU Meters With A Little Physics” →

Using A Laser To Blast Away A Bayer Array

August 9, 2021 by Stephen Ogier 47 Comments

A Bayer array, or Bayer filter, is what lets a digital camera take color photos. It’s an array of tiny color filters that sit on top of a camera’s CCD. The filter makes it so that each sub-pixel in the image sensor only sees red, green, or blue light. The Bayer filter is an elegant tool that gives us color digital photos, but what would you do if you wanted to remove one?

[Les Wright] has devised a way to remove the Bayer filter from the Raspberry Pi Camera. Along with filtering red, green, and blue light for their respective sensors, Bayer filters also greatly reduce the amount of UV and IR light that make it to the CCD sensor. [Les] uses the Raspberry Pi camera in his Pi-based Spectrometer, and he wants to remove the Bayer filter to improve and expand its sensitivity.

Of course, [Les] isn’t the first one to want to do this. Some have succeeded in physically scratching the filter off of the CCD, but because the Pi Camera has vital circuitry around the outside of the sensor, scratching the filter off would likely destroy the circuitry. Others have stripped it off using chemical means, so [Les] gave this a go and destroyed no small number of cameras in his attempt to strip the filter off with solvents like DMSO, brake fluid, and industrial paint stripper.

A look at the CCD, halfway through the process.

Inspired by techniques used in industry, [Les] eventually tried to use a several-kW nitrogen laser to burn off the filter (which seems appropriate given his experience with lasers). He built a rig that raster scans the laser across the sensor using stepper motors to drive micrometer bases. A USB microscope was included to allow progress to be monitored, and you can see a change in the sensor’s appearance as the filter is removed.

After blasting off the Bayer filter, [Les] plugged his improved camera into his home-built spectrometer and pointed it outside. The new camera gives the spectrometer much more uniform sensitivity and allows [Les] to see further into the IR and UV bands. The spectrometer can even detect the Fraunhofer lines—subtle dips in the sun’s spectrum from absorption by molecules in the atmosphere.

This is incredible for a DIY setup and instrument, and we can’t wait to see what [Les] does next to improve his measurements. If your spectrometry needs are more mass than visual, take a look at this home-built mass spectrometer. Home spectrometers aren’t just for examining light spectra—they can also be used to judge the ripeness of fruit!

Continue reading “Using A Laser To Blast Away A Bayer Array” →

A New Flying Car Illustrates The Same Old Problems

August 9, 2021 by Lewin Day 98 Comments

For almost as long as there have been cars and planes, people have speculated that one day we will all get around in flying cars. They’d allow us to “avoid the traffic” by flying through the air instead of sitting in snarling traffic jams on the ground.

The Klein Vision AirCar hopes to be just such a panacea to our modern traffic woes, serving as a transformable flying car that can both soar through the air and drive on the ground. Let’s take a look at the prototype vehicle’s achievements, and the inherent problems with the underlying flying car concept.

It Flies and Drives

The AirCar is a somewhat futuristic looking, yet simultaneously dated, vehicle. It’s a two-seater with a big bubble canopy for the driver and a single passenger. At the rear, there’s a propeller and twin-boom tail, while the folding wings tuck along either side of the vehicle in “car” mode. At the flick of a switch, the wings fold out and lock in place, while the tail extends further out to the rear. The conversion from driving mode to flight mode takes on the order of a few minutes. The powerplant at the heart of the vehicle is a 160-horsepower BMW engine which switches between driving the wheels and the propeller as needed.

Unlike some concepts we’ve explored in the past, the AirCar has successfully demonstrated itself as a working flying car without incident. Additionally, it did so as a single vehicular package, without removable wings or other such contrivances. On June 28th, 2021, it successfully flew from an airport in Nitra, Slovakia, down to the neighbouring city of Bratislava in 35 minutes – roughly half the time it takes by car. Company founder Stefan Klein was behind the controls, casually driving the vehicle downtown after the successful landing. Continue reading “A New Flying Car Illustrates The Same Old Problems” →

Vintage Displays Hack Chat With Fran Blanche

August 9, 2021 by Dan Maloney 1 Comment

Join us on Wednesday, August 11 at noon Pacific for the Vintage Displays Hack Chat with Fran Blanche!

In terms of ease of integration and density of the information that can be shown, it’s hard to argue with the fact that modern displays like LCD panels are anything but superior to the character-based displays of yore. Throw one into a project, add a little code from a few off-the-shelf libraries to drive it, and you’re on to the next job.

Efficient, yes, but what does this approach do for the engineer’s soul? What design itch does it scratch; what aesthetic does it celebrate? Nostalgic questions, true, and not every project lends itself to exploring old display technologies. But some still do, thankfully, and when the occasion calls for it, we’re glad that there are those out there who are still actively involved in the retro display community, making sure that what was once state-of-the-art technology is still able to be added to modern projects.

There’s no doubt that Fran Blanche is one of those passing the torch of vintage displays down to the next generation. You’ll certainly know Fran from her popular Fran Lab channel on YouTube, where in addition to about a million other interests, she has explored some really cool vintage displays: the Nimo cathode-ray tube, super-bright incandescent seven-segment displays, the delightfully strange “Bina-View”, and many, many more. Fran will stop by the Hack Chat to talk about all these retro displays, what she’s learned from collecting them, and how they shaped the displays we take so much for granted these days. Oh, and perhaps we’ll also talk about her upcoming ride on “G-Force 1” as well.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, August 11 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.