This Vintage LED Matrix Lives In A Gold Bathtub

April 3, 2021 by Donald Papp 9 Comments

Early LED displays came in all sorts of configurations. Because the LED was fairly new technology, all kinds of ideas were getting tried, and with all that work there was plenty of opportunity for hardware that didn’t make the cut to fall into obscurity. That’s exactly what happened to the Hewlett-Packard 5082-7002, a 5×7 LED matrix display with something many of its brethren didn’t: an oversized gold tub to sit in.

It doesn’t seem that these displays were ever used in any actual products, and its origins are a mystery, but the device itself was nevertheless assigned an HP part number. Beyond that, not much is known about them, but [Industrial Alchemy] reminds us that many early LED devices were poorly documented and never produced in any real quantities. They became forgotten hardware, waiting to be rediscovered.

The 5082-7002 has a oversized gold tub that makes the 5×7 LED matrix mounted inside look puny by comparison, and reading any display made from these units would be difficult because the large size of the device would mean a lot of empty space between each character or digit. But it’s definitely got a striking look to it, no doubt about that.

What’s neat is that the 5802-7002 actually showed up in a video we featured with a look back at cool old LED technology. If you would like to (briefly) see the HP 5802-7002 a bit closer under a microscope, here is a link to the video, cued to 2:19.

Over-Engineered Incandescent Numerical Display Shows Great Workmanship

April 1, 2021 by Donald Papp 18 Comments

Back before LED technology came into its own, displays used incandescent bulbs. These vintage incandescent displays weren’t necessarily big; the Eaton 925H-C fiber optic display, for example, has numbers barely 7 mm tall and packs two of them into a tiny area. Of course, the depth of the display module itself is huge by today’s standards; those components have got to go somewhere, after all.

This particular device is, in [Industrial Alchemy]’s words, “[d]ripping with the spending excess that only a bottomless military budget can provide… the Eaton 925H-C may not be a practical device, but it is certainly an impressive one.”

The way the display works is this: individual incandescent bulbs light up fiber optic light guides, which terminate on the face of the display in small dots to make up a numerical display. With only fourteen bulbs, the dots we see here clearly aren’t individually addressable; the two digits are most likely broken up into seven segments each, with three dots making up each segment.

No expense seems spared in the design and manufacture of these displays. Even the incandescent lamps have individual shock absorbers.

The sheer amount of workmanship in these displays is remarkable, and their design makes them easy to retrofit with LED technology instead of replacing the tiny incandescent lamps. In a stark contrast to all of the machined aluminum and gold plated contacts seen here in the Eaton 925H-C, take a look at this Soviet-era seven-segment incandescent display whose construction is far less sophisticated, but shows off its own clever engineering. We’ve also seen more modern DIY takes on the concept, using LED light sources and cured UV resin light pipes to get that vintage look to the displays.

Vintage Calculator Design Shows Just How Much We Take For Granted Today

February 20, 2021 by Donald Papp 14 Comments

[Amen]’s Rockwell 920 calculator from the 70s was a very impressive piece of hardware for its time. It sported a 16-digit display, a printer, and it could run programs. It even had a magnetic card reader/writer that could be used to store programs and data externally. Seen through today’s eyes, it was less like a calculator and more like what we would call a single-board computer. They are also a window into another era, a time when many of the electrical design assumptions we take for granted hadn’t happened yet. When the time came to dig into what made the calculator tick, [Amen] had a lot of work to do just to get basic tools running.

For example, [amen]’s Blue Pill (an open-source, multipurpose test and measurement tool) is, on one hand, the perfect tool to snoop on the inner workings. However, those inner workings happen to use negative logic at -17 Volts, which means a logical zero is -17 V and a one is 0 V. Oh, and it uses an oddball clock rate, to boot. Since the Blue Pill doesn’t support -17 V negative logic (does anything?) a bit of custom work was needed to craft an interface. Once that was working, the Blue Pill was off to the races.

The unfamiliar elements didn’t end there. The pins on each IC, for example, are in a staggered layout quite unlike the DIP pattern most of us (and our tools, breadboards, and IC clips) are familiar with. As for the processor itself, [amen] has access to low-level documentation on Rockwell processors and instruction sets, but the timing diagrams are puzzling until one realizes the processor has two clock inputs at two different frequencies, resulting in what [amen] describes as four separate “clock phases”.

These design decisions were certainly made for good reasons at the time, and they even have a certain internal harmony to them, but it’s still a window into an era when the elements underpinning much of what we now have and work with had not yet happened.

Check out the video embedded below to see [amen] explain what it took to hook the Blue Pill up to a Rockwell 920. Also, if you’d like to see one of these vintage machines demonstrated in all its functioning glory, here’s a video of one being put through its paces.

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Radon Monitor Recreates Steam Gauge With E-Ink

September 18, 2020 by Tom Nardi 11 Comments

While the full steampunk aesthetic might be a bit much for most people, those antique gauges do have a certain charm about them. Unfortunately, implementing them on a modern project can be somewhat tricky. Even if you’ve got a stock of old gauges laying around, you’ve still got to modify the scale markings and figure out how to drive them with digital electronics. While we’ve seen plenty of people do it over the years, there’s no debating it’s a lot harder than just wiring up an I2C display.

But maybe it doesn’t have to be. With his Rad-O-Matic, [Hans Jørgen Grimstad] created a pretty convincing “analog” gauge using a small e-ink panel. Of course it won’t fool anyone who gives it a close look, but at a glance, you could certainly be forgiven for thinking it was some kind of vintage indicator. Especially with the cracked and stained Fresnel lens he put in front of it.

For this project [Hans] used a LilyGo T5, which combines an ESP32 with a 2.13 inch electronic paper display. These are presumably meant to be development boards for digital signage applications, but they occasionally show up in hacker projects since they’re so easy to work with. The board pulls data from a RD200M radon sensor over a simple UART connection, and the current reading is indicated by a “needle” that moves across a horizontal scale on the display.

On its own, it wouldn’t look very vintage. In fact, quite the opposite. But [Hans] really helped sell the look on this project by designing and 3D printing a chunky enclosure and then weathering it to make it look like it’s been kicking around since the Cold War.

If you don’t feel like faking it, we’ve seen some very impressive projects based on authentic vintage gauges. As long as you don’t mind tearing up hardware that’s likely older than you are, putting in the extra effort necessary for a convincing modification can really pay off.

[Thanks to Tarjei for the tip.]

World Radio Lets Your Fingers Do The Walking

September 12, 2020 by Tom Nardi 9 Comments

Listening to radio from distant countries used to take a shortwave rig, but thanks to the Internet we can now pull in streams from all over the globe from the comfort of our own desktop. With a few clicks you can switch between your local news station and the latest in pop trends from Casablanca. But as convenient as online streaming might be, some folks still yearn for the traditional radio experience.

For those people, the Raspberry Pi World Radio by [Abraham Martinez Gracia] might be the solution. Built into the body of a 1960s Invicta radio, this Internet radio uses a very unique interface. Rather than just picking from a list of channels, you use the knobs on the front to pan and zoom around a map of the world. Streaming channels are represented by bubbles located within their country of origin, so you’ll actually have to “travel” there to listen in. The video after the break gives a brief demonstration of how it works in practice.

We’ll admit it might become a bit tedious eventually, but from a visual standpoint, it’s absolutely fantastic. [Abraham] even gave the map an appropriately vintage look to better match the overall aesthetic. Normally we’d say using a Raspberry Pi 4 to drive a streaming radio player would be a bit overkill, but considering the GUI component used here, it’s probably the right choice.

Of course we’ve seen Internet radios built into vintage enclosures before, and we’ve even seen one that used a globe to select the station, but combining both of those concepts into one cohesive project is really quite an accomplishment.

Continue reading “World Radio Lets Your Fingers Do The Walking” →

Retrocomputing Spray Paints: Amiga Beige, Commodore, And ATARI Grey

September 1, 2020 by Donald Papp 19 Comments

[retrohax] has provided vintage computer guidance for years, and part of that guidance is this: sometimes using paint as part of restoration is simply unavoidable. But the days of tediously color-matching to vintage hardware are gone, thanks to [retrohax] offering custom-mixed spray paints in Amiga 500 Beige, C-64 Beige, and ATARI ST/SE Grey. (At the moment only delivery within Poland is available due to shipping restrictions, but [retrohax] is working on a better solution.)

As a companion to making these vintage colors available, there is also a short how-to guide on how to properly prep and spray paint a computer case for best results that talks a little about the challenges in color matching to vintage hardware, and how getting custom paints mixed makes life much easier. Hackers may value making do with whatever is available, but we can also appreciate the value of having exactly the right material or tool for the job.

It’s not every day we see someone mixing custom spray paint colors, but off the shelf options don’t always cut it. Another example of getting specialty materials made from the ground up is custom plywood specifically designed for laser-cutting puzzles, something done because the troubles that came with off-the-shelf options were just not worth the hassle.

Antique Oscilloscope Gets New Home And Purpose

September 1, 2020 by Bryan Cockfield 11 Comments

As the pace of technology charges blindly forward, a lot of older tools or products get left in the dust, forgotten to most but those left with them. This doesn’t mean they’re useless, though. In fact, old technology that continues to survive in the present tends to be more robust and sturdy than most modern, cheap replacements. While this might be survivorship bias, this is certainly true in particular of oscilloscopes. Rugged CRTs in large metal housings with discrete through-hole components in simple layouts made them reliable, but they’re heavy, bulky, and lack features of modern instruments. With some modifications, though, you can give them a new home and keep their vintage aesthetic.

[BuildComics] had just such an oscilloscope on hand and set out to make it into something useful but aesthetically pleasing as well. With a small circuit board, formerly available as a kit from Sparkfun/Dutchtronix but now only available if you can build them yourself, the cathode ray tube can be modified to output not waveforms but rather a working clock face. The donor oscilloscope was a Heathkit IO-102 which was fine for its time but is now lacking, so the CRT was removed from its housing and placed in a custom-built enclosure with a 40s radio style that suits its new purpose well.

Seeing old hardware that is past its prime being put to work in a new way is great, both from a technical standpoint and also because that’s usable hardware that’s being kept out of the landfill. Oscilloscopes are popular for projects like these too since they are relatively easy to understand and modify. Besides being used as clocks, we’ve also seen them modified to play video games such as Pac-Man.