Category Archives: Vintage Technology

Retro-tech Style in the New York Times

Component Wine Charms

I’m excited to be included in an article on retro tech style in the New York Times today, titled Nintendo 64s and Vintage PlayStations as Home Décor.

Not surprisingly, these techie hobbyists share their passion in online communities. One of the more popular forums is a D.I.Y. tech blog run by Evil Mad Scientist Laboratories, a family company in Sunnyvale, Calif., that produces open-source hardware. The site features tutorials on making earrings out of linear regulator chips, wine charms from capacitors and a wooden footstool in the shape of a classic 555 integrated circuit chip from the ’70s.

Hard Drive Earrings

Wearing my new earrings

The newest in my collection of geeky jewelry: glass hard drive platter earrings.

tiny platters

We picked up a tray of tiny glass platters at a local surplus shop some time ago, marked “Tear Down Qty: 25 pcs.”

CF card for comparison

These one inch platters were used in Microdrives, which were designed to fit into CompactFlash card slots. (Shown with CompactFlash card above for scale.) They were used in (among other things) the iPod mini. After 2006, CF cards outpaced the capacity of the fragile Microdrives, and they’re no longer manufactured.

Earrings

The platters are attached to the earring hooks with magnet wire. They’re incredibly reflective, and everywhere I wear them, spots of light are dancing around me.


Related: Hard Drive Wind Chimes

Podtique: podcast player in an antique radio

Podtique: Antique Podcast Player

Our friend Rick stopped by to show us his latest project, which he calls Podtique: a podcast player built into an antique radio cabinet. Using the original knobs, you tune in on “stations” which play different podcasts, with realistically generated static in between.

Podtique

The whole thing is run on a BeagleBone Black, and uses NeoPixel backlighting behind the dial. He’s written up the build on his blog, posted his code on github, and shared a heap of build photos in an album on flickr.

A Vintage Melody Synthesizer IC

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Leigh Klotz, author of Ham Radio for Arduino and PICAXE, gave us this interesting chip from the 80’s to play with: a UM3482A “Multi Instrument Melody Generator” IC.  While not quite rare, it is a bit of a vintage curiosity these days, and we wired one up to see what exactly it does.

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The vintage Radio Shack Archer package it came in was minimalist (though not quite this minimalist as it came to us– imagine that the chip were still there in the bubble). It promises not just 12 tunes, but circuit diagrams as well.

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This Archer-branded datasheet (including the promised circuit diagrams) came stapled to the back.  You can download a readable copy of the manufacturer’s original datasheet here.

“A mask-ROM-programmed multi-instrument melody generator, implemented in CMOS technology. It is designed to play the melody according to the previously programmed information and is capable of generating 12 songs with 3 different effects: piano, organ, and mandolin.”

Amongst the twelve musical selections are London Bridge, Row Row Row Your Boat, Oh My Darling Clementine, and (of course) Happy Birthday.  Suggested applications included toys, door bells, music boxes, and telephones.  (File under: Customized ringtones of the 80’s?)

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The three little graphs in the upper right show the three different timbres (the “instruments,” in the phrase “multi-instrument”) in terms of amplitude versus time. The other diagrams show how to wire it up to a speaker and how to configure the various inputs to select which song to play and so forth.

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We breadboarded up a sample circuit from the datasheet, substituting with parts we had on hand, including a little magnetic buzzer as the speaker. A 2xAA battery holder is connected up to the power and ground rails.  There is a momentary button switch to select the next melody in the set, and a row of DIP switches to set the configuration options.

And sure enough, it plays melodies.

LED Metronome


After seeing our Larson Scanner kit, Martin shared this LED metronome project with us. Martin says:

It was designed as a “Visual Metronome”  So a learning music student could help see the timing by watching the green light.  There was to be an optional clicking sound  by using a small solenoid for the ticking – I chose that in place of a speaker for a more authentic sound.

The timing is a standard 555 timer which is fed to 7442 BCD to DECIMAL counter.  Next chip is a 74193 UP/DOWN counter.  When the count hits the last number, it sends a pulse to reverse the count or start over – depending on the toggle switch on the side.

There is also a pot on the 555 to control the speed.  All this was made in one night while I was working the graveyard shift.

The entire LED display was hand wired using a manual wire-wrap tool.

The chip pin labels on the back of the perf board are a particularly awesome relic of a different era of electronics assembly. Thanks for sharing your project photos and video with us!

Modern manufacturing for vintage autos

Both mirrors

Last year, I wrote about a case of 3D printed parts being used for a vintage car. This year, another fine example of modern manufacturing and prototyping techniques being used for a vintage vehicle showed up on my doorstep when my parents stopped by during a road trip in my dad’s 1934 Dodge Brothers pickup

Passenger side mirrors on cars and trucks used to be a luxury, add-on, or aftermarket item— if they were even available at all. My dad’s truck never had one. In the intervening years, many states have made side mirrors a requirement, and having them makes safely driving a vintage vehicle much easier. So how did he get the matching one you see in the picture above?

Passenger side mirror

He did what pretty much anyone can do these days: he had the driver side one 3D scanned, had a CAD model made up from the scan and then mirrored it. The model was then 3D printed and sand cast in aluminum. After some finishing work and paint, it looks fantastic.

Side mirror mount showing standoff

However, geometry reared its head: it turns out that because the driver sits on one side of the car, a perfectly mirrored mirror mount doesn’t put the mirror in quite the right place. As a temporary fix, he added a standoff to correct the position of the mirror. After returning from the road trip, he’ll adjust the CAD model and have a new one printed and cast. Since the world of vintage cars is a close-knit one, he has already had requests for additional units from friends in the community, and making more will be straightforward from the digital master.

He’s had a few other components made using scanning and digital manufacturing techniques, including a laser cut insulation board for between the engine compartment and the cab. These techniques are a perfect fit for a community with low-volume needs for custom, unavailable, or never before made parts.

Soldering Tip Tinning with Sal Ammoniac


If you solder, you’ve likely come across an “untinned” tip at some point— that’s when the tip of your soldering iron loses its shine, and doesn’t easily wet to solder any more.

Once your tip gets this way, it doesn’t make nearly as good of a thermal contact to whatever you are trying to solder, and it simply doesn’t work well. Soldering can take 2-10 times as long, and that isn’t good for your circuit board, components, or mental health.

You can sometimes re-tin the tip by melting fresh solder onto it, but that can be challenging, because the whole problem is that the tip isn’t melting solder. It’s particularly hard to keep tips tinned with modern lead-free solder, because it needs to get even hotter to begin melting.  If you get to this point, you might think about even replacing the tip.

But before you throw that tip away, instead consider using one of the “old standard” solutions, which is to refurbish the tip with a tip-tinning compound. And we came across the most classic of them in one of the most unexpected locations.  Continue reading Soldering Tip Tinning with Sal Ammoniac

The Power of the Digi-Comp II

Last fall, we built an oversized Digi-Comp II for MIT, which we’ll be posting about in the near future. Today, MIT computer science professor Scott Aaronson published a short “paperlet” about the computational capabilities of the Digi-Comp II on his blog, Shtetl-Optimized:

…it’s amazing that such a simple contraption of balls and toggles could already take us over the threshold of universality.  Universality would immediately explain why the Digi-Comp is capable of multiplication, division, sorting, and so on.  If, on the other hand, we don’t have universality, that too is extremely interesting—for we’d then face the challenge of explaining how the Digi-Comp can do so many things without being universal.

Ingenious 1970’s Technology: The Flip Flash

FlipFlash 5

Once upon a time, cameras did not come with LED illumination or even xenon strobes, but rather with a socket that could fire a one-time-use flashbulb.

An advance from this was the “flip flash” cartridge which held 8 or 10 flash bulbs, ganged up so that you could take one photo after another, without pausing to swap bulbs. Each time that you took a picture (exposing actual film!), the next flashbulb in the cartridge would fire.

But you might ask a tricky question here: How does it know which bulb to fire next?

Continue reading Ingenious 1970’s Technology: The Flip Flash