Author: Adam Fabio

724 Articles

Vintage Computer Festival Southern California

October 16, 2023 by 13 Comments

The Vintage Computer Festival is coming to sunny Southern California in February 2024. That’s right, bring your Commodores, your Tandys,  your PDP-11s, and Altairs. The world of retrocomputing will be open to vendors, visitors, and exhibitors at The Hotel Fera Events Center in Orange, California on February 17th and 18th, 2024.

If you’re thinking there already is a VCF out west, you’d be right. VCF West was held in August at the Computer History Museum. The CHM is in Mountain View, California. That puts it nearly at the epicenter of the microcomputer revolution of the ’70s and ’80s.

Southern California still had plenty of computer enthusiasts though. For the non-geographically inclined amongst us, SoCal is nearly 6 hours from Mountain View by car.  We’re sure we’ll see many familiar faces at SoCal, along with plenty of new ones.

The Vintage Computer Federation holds several events across the country each year. You might have heard some music from VCF Midwest 2023 back in September. Hackaday was also out in force at VCF East this year, where our own [Bil Herd] moderated a panel of vintage computer YouTubers including [Usagi Electric], [Adrian’s Digital Basement], and [FranLab].

The Device That Won WW2: A History Of The Cavity Magnetron

August 28, 2023 by 55 Comments

[Curious Droid] is back with a history lesson on one of the most important inventions of the 20th century: The cavity magnetron. Forged in the fighting of World War II, the cavity magnetron was the heart of radar signals used to identify attacking German forces.

The magnetron itself was truly an international effort, with scientists from many countries providing scientific advances. The real breakthrough came with the work of  [John Randall] and [Harry Boot], who produced the first working prototype of a cavity magnetron. The device was different than the patented klystron, or even earlier magnetron designs. The cavity magnetron uses physical cavities and a magnetic field to create microwave energy.  The frequency is determined by the size and shape of the cavities.

While the cavity magnetron had been proven to work, England was strapped by the war effort and did not have the resources to continue the work. [Henry Tizzard] brought the last prototype to the USA where it was described as “the most valuable cargo ever brought to our shores”. The cavity magnetron went on to be used throughout the war in RADAR systems both air and sea.

Today, many military RADAR systems use klystrons or traveling wave tube amplifiers due to requirements for accurate frequency pulses.  But the cavity magnetron still can be found in general and commercial aviation RADAR systems, as well as the microwave ovens we all know and love.

Check the video out after the break.

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Tiny Spheres Hiding In Your Display

August 20, 2023 by 6 Comments

Liquid crystal and Organic LED displays have revolutionized portable computing. They’re also made of glass. Which presents a problem: How do we get electrical signals from fiberglass circuit boards to the glass displays? The answer is double-sided adhesive tape. But we’re not talking about packing tape here. As [Breakingtaps] explains,  this tape has a trick up its sleeve.

The magic is that the tape conducts only in the vertical plane. Even more so, any two conducting sections of the tape are insulated from each other. How does it do that? Magic beans balls, of course!

The tape and adhesive are insulators. Embedded in the adhesive are tiny spheres. The spheres are made of plastic and coated with metal. When the tape (also known as ACF or Anisotropic Conductive Film) is pressed between a PCB with conductors and glass, a few spheres are squished down between the layers. Electrical signals pass between the squished spheres, allowing an image to be displayed on the glass screen. The final step uses heat and pressure to bond the adhesive and cure it. You can also get the material in paste form if you don’t like the tape.

The system works so well that it can be used for connections from a silicon chip directly to the glass.  This is how many display controllers are mounted right to the module — definitely an improvement on the rubber strips used on LCDs of the past.

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PCjr WebServer Hits 2500 Hours Uptime

July 20, 2023 by 23 Comments

When [Mike] fired up his PCjr webserver back in March, he probably wasn’t expecting it to go viral. 2640 hours later, here we are! Not only has his machine run continuously for over 110 days, it also is surviving a global hug of death. All of this is thanks to some very special software.

We see lots of old machines here on Hackaday. We also see lots of minimal web servers. But we don’t see many that can run for thousands of hours, offering up to 8 simultaneous connections. Curious if jr is still up? Check brutmanlabs.org. The whole website is hosted on the 40-year-old machine. If you want to be a bit more kind, here’s a direct link to the text-only status page. While many of those hours were idle, currently lots of folks are hitting that little V20 CPU, so please give it a few seconds to respond.

The PCjr has a few upgrades — the aforementioned V20 CPU upgrade, a jrIDE sidecar, and a memory upgrade to 736 kB to name a few.  Ethernet connectivity is via a Xircom parallel port adapter – which is circa 1993.  The operating system is IBM PC DOS 5.02. One thing to note is that all these upgrades were possible back in the mid-1980’s when the PCjr was still current.  [Mike] could run the system with an MFM hard drive, an ISA ethernet card (via an adapter), and use the original CRT monitor. Older DOS versions would work too — though partition sizes would be limited. The “modern” conveniences are just to keep from wearing out vintage hardware which is quickly becoming rare.

The real glue that holds this all together is [Mike’s] own software: mTCP. mTCP is a full set of tools for running internet applications on systems running MS-DOS or a compatible OS. We’ve seen quite a few mTCP projects over the years.  [Mike] has worked tirelessly testing the software, ensuring that it is stable and reliable.

Software is never perfect though – one thing [Mike] didn’t implement is a log roller. Since he has logging turned on, the PCjr was slowly filling up its hard drive. Once the drive was full, mTCP would perform an orderly shutdown — but the uptime will be reset.  [Mike] was able to go in and switch off logging with  DOS’s DEBUG command. A live patch is not the way one would normally update software – but the fact that he was able to do it shows how deep [Mike’s] knowledge of the software goes.

[Mike] has even provided a live stream recording of the little PCjr handling requests from all over the globe.

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Building A MiniPET Is Better With Friends

July 17, 2023 by 4 Comments

[Taylor and Amy] love taking on retro computer projects. This week they’re building a MiniPET from Tynemouth and The Future is 8 Bit.  It’s a pretty awesome kit which sadly isn’t available anymore. Taylor bought one of the last ones as part of a charity sale at the 2023 Vintage Computer Festival Southwest.

If you haven’t seen their YouTube channel yet, check it out! The two have been best friends since 1984. Their channel has just the right mix of education and comedy, with pacing fast enough to keep things interesting. It’s really refreshing to see two people enjoying a project together.

The MiniPET is of course a reproduction of the hardware in the Commodore PET, the machine which predated the VIC-20 and of course the Commodore 64. The kit starts with installing a few discrete parts — resistors,  capacitors, and diodes.  Then come the IC sockets. [Taylor and Amy] ran into a bit of trouble when it came time to install the chips. While installing the 40-pin 65C21 Peripheral Interface Adapter (PIA), one pin bent under the socket. [Taylor] popped the chip back out, and replaced it — which resulted in 3 bent pins!

Anyone who’s installed new DIP parts has been through this. The pins are always bent out a bit from the factory. The old “Bend it in using a table” method usually works — but if you want perfect pins, try a pin straightener. These versatile tools can even be 3D printed.

Once the pin problems are solved, it’s time to power up the kit and see if it will work.  That’s when we get to see that magic moment when a project first comes to life. Check out the video – you’ll see what we mean.

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Saying Goodbye To Don Lancaster

July 2, 2023 by 63 Comments

The electronics world has lost a guru. On June 7th this year, Don Lancaster passed away. [Brad] from Tech Time Traveller paid tribute to Don in a recent video. Don Lancaster was perhaps best known as the designer of the TV Typewriter.  The Typewriter drew characters on a TV screen when the user typed on a keyboard. It was the fundamental part of a simple terminal. This was quite an accomplishment in 1973 when the article was first published.

Don embodied the hacker spirit by figuring out low-cost (cheap) ways to overcome obstacles. His genius was his ability to communicate his methods in a way even non-technical people could understand. Keyboards are a great example. Back in the 1970’s a simple keyboard cost hundreds of dollars. Don figured out how to build one from scratch and published an article explaining how to do it.

Like many people we cover here on Hackaday, Don was quite a character. His website layout hasn’t changed much since the 1990’s, but the content has grown. To say he was a prolific writer would be an understatement. PostScript, Magic Sinewaves, and patents are just a few of his favorite topics. Don’s recent work involved the research of prehistoric canals in the American Southwest.

Everyone here at Hackaday sends our deepest condolences to Don’s family.

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Take A Ride In The Bathysphere

June 13, 2023 by 5 Comments

[Tom Scott] has traveled the world to see interesting things.  So when he’s impressed by a DIY project, we sit up and listen. In this case, he’s visiting the Bathysphere, a project created by a couple of passionate hobbyists in Italy. The project is housed at Explorandia, which based on google translate, sounds like a pretty epic hackerspace.

The Bathysphere project itself is a simulation of a submarine. Sounds simple, but this project is anything but.  There are no VR goggles involved.  Budding captains who are up for the challenge find themselves inside the cockpit of a mini-submarine. The sub itself is on a DIY motion platform. Strong electric motors move the system causing riders to feel like they are truly underwater. Inside the cockpit, the detail is amazing. All sorts of switches, lights, and greebles make for a realistic experience.  An electronic voice provides the ship status, and let’s the crew know of any emergencies. (Spoiler alert — there will be emergencies!)

The real gem is how this simulation operates. A Logitec webcam is mounted on an XY gantry. This camera then is dipped underwater in a small pond. Video from the camera is sent to a large monitor which serves as the sub’s window. It’s all very 1960’s simulator tech, but the effect works. The subtle movements of the simulator platform really make the users feel like they are 20,000 leagues under the sea.

Check out the video after the break for more info!

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