4-bit Adder Built From Mechanical Relays

April 26, 2014 by Mike Szczys 20 Comments

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Would you consider this to be doing math the old-fashioned way? Instead of going with silicon-based switching (ie: transistors) this 4-bit adder uses mechanical relays. We like it for its mess of wires (don’t miss the “assembly” page which is arguably the juiciest part of the project). We like it for the neat and tidy finished product. And we like it for the clicky-goodness which surely must bloom from its operation; but alas, we didn’t find a video to stand as testament to this hypothesis.

The larger of the two images seen above is from the register memory stage of the build. The black relay in the bottom right is joined by a ring of siblings that are added around the perimeter of the larger relays before the entire thing is planted in the project box.

Sure, simulators are a great way to understand building blocks of logic structures like an adder. But there’s no better way to fully grip the abstraction of silicon logic than to build one from scratch. Still hovering on our list of “someday” projects is this wooden adder.

[Thanks Alex]

Retrotectacular: The Science Of Derailing Trains

April 22, 2014 by Mike Szczys 31 Comments

Look closely above and you’ll see there’s a section of track missing. There are actually two, a section from each side has been plucked out with a pair of eight-ounce plastic explosive charges — and yet the train keeps barreling onward. The World War II era reel is demonstrating some military testing of the effect of damaged tracks on a train. The amount of missing track the train can stand up to came as quite a surprise for us!

The test setup itself is neat. An old derelict locomotive is used. It, as well as a number of trailing cars, is pushed by a functioning engine from behind. Once up to about 26 MPH the pusher stops and the rest keep going. There are many tests, starting with just a few inches of track missing from one side. This gap is increased, then gaps are added both sides, then the two sides are offset. Even a 5-foot gap is crossed easily by the locomotive. The weak link turns out to be the empty cars. We suppose their mass is small enough that they can’t rely on inertia to keep them on the straight path.

If you don’t appreciate the destructive nature of this Retrotechtacular installment, you can still get your train fix. There is another offering which shows off the modernization of a signaling system.

Continue reading “Retrotectacular: The Science Of Derailing Trains” →

Hackaday Links: April 20, 2014

April 20, 2014 by Mike Szczys 23 Comments

[Josh] hit the same issue we’ve faced before: cable modems don’t match a form factor and usually don’t make themselves easy to mount on something. We could complain about routers as well, but at least most of those have keyhole slots so you can hang them on some screws. Inspiration struck and he fabricated his own rack-mount adapter for it. Velcro holds it in place, with a cutout bezel to see the status lights and an added fan to keep things cool.

Here’s a pair of strange but possibly interesting ones that were sent in separately. The first is an analysis of how much energy short-run CNC prototyping consumes versus traditional manufacturing. The other is an article that [Liz] wrote about getting started with CNC mill bits. She says she compiled all that she learned as she was getting started in the field and wants to save others the effort.

This one goes back several years, but who doesn’t love to hear about a voice-controlled wheelchair?

So you can solder QFN parts but you can’t hammer a nail straight into a piece of wood? The answer, friend, is a laser guided hammer. Someone hire this [Andybot] person, because the solution to the problem shows the ability to out-think an interesting dilemma: how do you put a laser in a hammer head and still use it to hit things?

We’ve seen a lot of these long-range WiFi hacks over the years. This one is worth looking at because of the work done to create an outdoor mount that will stand the test of time.

And finally, we’re still really fond of this 2-bit paper processor that helps you wrap your brain around what’s going on with those silicon wafers that rule our everyday lives. [glomCo] liked it as well, and actually coded an emulator so that you can play with it without printing anything out on paper. We think it takes away some of the fun, but what an excellent programming exercise!

We’re Not Joking Around; Something BIG Is Coming

April 18, 2014 by Mike Szczys 95 Comments

Hackaday Something BIG Logo Countdown timer, a special presentation on the first of this month, and now there’s been some weekly mystery posts. What are we playing at? We’re not playing. This is real.

That timer is now below the 10-day mark and with every passing minute we become more giddy about the unrelenting awesome that is to come. Want to know what we’re talking about without waiting until the end? Are you a clever person? Then you might just be able to figure it all out. Try to unlock the clues from past weeks, and hit the Freenode ##hackaday channel on IRC if you need some hints (we’re certainly not going to post spoilers here).

We wouldn’t mind some help with a whisper campaign as well. Spout your conspiracy theories, and your delight at solving our puzzles to whoever will listen. Get it right and you can do the “I told you so” thing for the rest of the…. oops, that would be telling.

Retrotechtacular: The Cryotron Computer

April 15, 2014 by Mike Szczys 14 Comments

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Have you ever heard of a Cryotron Computer before? Of course not. Silicon killed the radio star: this is a story of competing technologies back in the day. The hand above holds the two competitors, the bulkiest one is obviously the vacuum tube, and the three-legged device is what became a household name. But to the right of that tube is another technological marvel that can also be combined into computing machines: the cryotron.

[Dudley Allen Buck] and his contributions to early computing are a tale of the possible alternate universe that could have been cryotrons instead of silicon transistors. Early on we find that the theory points to exotic superconductive materials, but we were delighted to find that in the conception and testing stages [Buck] was hacking. He made his first experimental electronic switches using dissimilar metals and dunking them in liquid helium. The devices were copper wire wrapped around a tantalum wire. The tantalum is the circuit path, the copper wire acts as the switch via a magnetic field that alters the resistance of the tantalum.

The name comes from the low temperature bath necessary to make the switches work properly. Miniaturization was the key as it always is; the example above is a relatively small example of the wire-wound version of the Cryotron, but the end goal was a process very familiar to us today. [Buck] was searching for the thin film fabrication techniques that would let him shoe horn 75,000 or more into one single computing platform. Guess who came knocking on his door during this period of his career? The NSA. The story gets even more interesting from there, but lest we rewrite the article we leave you with this: the technology may beat out silicon in the end. Currently it’s one of the cool kids on the block for those companies racing to the quantum computing finish line.

[Thanks Frederick]

Retrotechtacular is a weekly column featuring hacks, technology, and kitsch from ages of yore. Help keep it fresh by sending in your ideas for future installments.

Hackaday Links: April 13, 2014

April 13, 2014 by Mike Szczys 13 Comments

Check out this Pokemon Yellow cartridge for Super Nintendo. Wait, what? That is a Game Boy game! Well there is a Super Gameboy cartridge that lets you play them on SNES. This mashes the guts of the two into a custom-decorated SNES cart. Now if you’re more interested in the guts of that Super Game Boy cartridge you’ll want to check out this classic hack which dumped the ROM from it. [Thanks Nick]

Here are a couple of interesting things from our friends over at Adafruit. First off, they have a high-res gallery of the Raspberry Pi compute module and carrier boards which we heard about earlier in the week. Also, the latest Collin’s Lab has a great video on soldering. We especially appreciated the discussion of soldering iron tips and their effect on heat transfer.

[Marius] got tired of the static shock from the office coat rack. You know, like the scene straight out of Office Space? But he didn’t disassemble the infrastructure to solve the issue. Instead he connected it directly to ground. Just make sure you stick the wire in the correct hole!

It’s as if Hackaday is on a quest for the most perfect DIY cyclonic separator. Here’s the latest offering which you can cut out from sheet stock by hand. It’s the alternative for those of us without access to a 3D printer.

If you think it’s too difficult to build what we refer to as a Daft Punk table you need to check out what [Dan] pulled off. He proves that your LED matrix coffee table project doesn’t have to take up a ton of time or cost an exorbitant amount of cash.

We should have mentioned this to you before the weekend so you’d have something to watch: you can now download BBS: The Documentary from the Internet Archive. We’ve watched the entire thing and it’s fantastic. If you know what a dial-up modem handshake sounds like, you’re going to be awash in nostalgia. If you don’t know the delight of those sounds you need to watch this and see how things used to be back in the day when connecting your computer to a network definitely wasn’t what the cool kids were doing. [Thanks Larry]

Fail Of The Week: Rewiring Robosapien

April 10, 2014 by Mike Szczys 34 Comments

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Our first thought was “check out all of those TO-92 components!”, but then we saw the wiring nightmare. [Tom] picked up a Robosapien from an estate sale for just $10. Most hackers couldn’t resist that opportunity, but the inexpensive acquisition led to a time-consuming repair odyssey. When something doesn’t work at all you crack it open to see what’s wrong. He was greeted with wiring whose insulation was flaking off.

This is no problem for anyone competent with a soldering iron. So [Tom] set to work clipping all the bad wire and replacing it with in-line splices. Voila, the little guy was dancing to his own tunes once again! But the success was short-lived as the next day the robot was unresponsive again. [Tom] plans to do some more work by completely replacing the wires as soon as he receives the replacement connectors he ordered. So what do you think, is this an issue that will be resolved with a wire-ectomy or might there be actual damage to the board itself?

Fail of the Week is a Hackaday column which runs every Wednesday. Help keep the fun rolling by writing about your past failures and sending us a link to the story — or sending in links to fail write ups you find in your Internet travels.