The Alexanderson Transmitter: Very-low Frequency Radio Rides Again!

June 27, 2015 by 44 Comments

Is your ham radio rig made of iron and steel? Is it mechanically driven? Classified as a World Heritage Site? We didn’t think so. But if you’d like to tune in one that is, or if you’re just a ham radio geek in need of a bizarre challenge, don’t miss Alexanderson Day 2015 tomorrow, Sunday, June 28th

The Alexanderson Transmitter design dates back to around 1910, before any of the newfangled tube technology had been invented. Weighing in at around 50 tons, the monster powering the Varberg Radio Station is essentially a high-speed alternator — a generator that puts out 17.2 kHz instead of the 50-60 Hz  that the electric companies give us today.

Most of the challenge in receiving the Alexanderson transmitter broadcasts are due to this very low broadcast frequency; your antenna is not long enough. If you’re in Europe, it’s a lot easier because the station, SAQ, is located in Sweden. But given that the original purpose of these behemoths was transcontinental Morse code transmission, it only seems sporting to try to pick it up in the USA. East Coasters are well situated to give it a shot.

And of course, there’s an app for that. The original SAQrx VLF Receiver and the extended version both use your computer’s sound card and FFTs to extract the probably weak signal from the noise.

We scouted around the net for an antenna design and didn’t come up with anything more concrete than “few hundred turns of wire in a coil” plugged into the mic input.  If anyone has an optimized antenna design for this frequency, post up in the comments?

Thanks [Martin] for the tip!

Custom Downdraft Fume Extractor for Soldering

Downdraft Fume Extractor Saves Your Lungs

June 27, 2015 by 21 Comments

When you’re soldering, smoke rises from your iron. That smoke is full of a variety of chemicals, depending on what type of solder you’re using, but it’s almost certainly not good for you. That’s why you can buy fume extractors to suck smoke away.

But benchtop extractors tend to suck, and not in the way they’re supposed to. It can be hard to get the extractor to pick up all the fumes, leaving fumes that float into your face.

Over at Other Machine Co., they built up a custom downdraft fume extractor to solve this problem. The downdraft extractor is a table that you work on, providing downwards suction that grabs the fumes. Their table uses a standard MERV13 air filter that’s rated to trap particles as small as 1.0–0.3 μm. Cooling fans provide the airflow, and a piece of perforated sheet metal acts as a work surface.

The table works great for soldering, and is also helpful for working with other chemicals like adhesives and solvents. DXF files for the frame parts are provided, and everything else can be sourced from McMaster.

Human-Machine Interface Projects At TEI 2016

June 27, 2015 by 2 Comments

For many of us, interacting with computers may be as glorious as punching keys and smearing touch screens with sweaty fingers and really bad posture. While functional, it’s worth reimagining a world where our conversation with technology is far more intuitive, ergonomic, and engaging. Enter TEI, an annual conference devoted to human-computer interaction and a landmark for novel projects that reinvent the conventional ways we engage our computers. TEI isn’t just another sit-down conference to soak in a wealth of paper talks. It’s an interactive weekend that combines these talks with a host of workshops provided by the speakers themselves.

Last year’s TEI brought us projects like SPATA, digital calipers that sped up our CAD modeling by eliminating the need for a third hand, and TorqueScreen, a force-feedback mechanism for tablets and other handhelds.

Next February’s conference is no exception for new ways to interact with novel technology. To get a sense of what’s to come, here’s a quick peek into the past from last year’s projects:

Continue reading “Human-Machine Interface Projects At TEI 2016” →

KeyMouSerial Solves Your Raspberry Pi Keyboard Problems

June 27, 2015 by 36 Comments

All laptops have a working keyboard and mouse built into them, the only problem is that you can’t use these tools on other computers that don’t have them. At least, until now. [Peter] has created the KeyMouSerial in order to use his laptop’s keyboard and mouse as physical devices on his Raspberry Pi, finally freeing the bonds holding our laptops’ human interface devices back.

The software for KeyMouSerial copies keystroke and mouse information and sends this out via a serial port on his laptop (using a USB to serial adapter). From there the information is translated by an Arduino into HID commands which are sent via USB to the target computer, in this case a Raspberry Pi. It’s a pretty elegant solution to carrying a bulky keyboard and mouse along just for a Raspberry Pi, or for any computer that might not have access to a network and SSH.

[Peter] has also been working on using his iPod as a serial-to-USB converter, so if you’re a Rockbox developer and want to help out then drop him a line. All of the software is available (for Windows, Mac, or Linux) including the Arduino sketch if you want to try this software out for yourself. And, if you don’t want to turn a computer into a keyboard and want to go the other direction and turn a keyboard into a computer, that is also an option.

Hackaday Prize Entry: Lose Yourself To Dance

June 26, 2015 by 8 Comments

Not every project for The Hackaday Prize needs to solve a pressing concern, save the planet, or help people. Sometimes, it just needs to be cool. [Jeremy]’s project is certainly cool. He’s building a touch-sensitive disco floor for the awesomeness of Saturday Night Fever combined with the technical complexity of the Billy Jean music video.

We’ve seen a few disco floor builds over the years, and for the most part, [Jeremy] isn’t straying too far from a well-tread path. He’s using LED strips to light his build, cutting the frame for the floor out of plywood and translucent squares, and using an ATMega to control each panel. So far, nothing out of the ordinary.

The trick to this build is that every square has a capacitive touch sensor. Underneath each translucent panel is a bit of wire mesh. Because the disco floor has 144 nodes, running the standard capacitive sensor library just wouldn’t work; the delay in measuring each node adds up very fast. By rewriting [Paul Stoffregen]’s capacitive sensor library, [Jeremy] was able to run many panels at once.

Right now [Jeremy] has a single panel that responds equally well to bare feet as it does to motorcycle boots. It’s exactly what you need in an interactive dance floor, and we can’t wait to seen the entire floor running.

The 2015 Hackaday Prize is sponsored by:

water computer

Manipulating Matter In A Digital Way

June 26, 2015 by 9 Comments

On a fundamental level a computer’s processor is composed of logic gates. These gates use the presence of electricity and lack thereof to represent a binary system of ones and zeros. You say “we already know this!” But have you ever considered the idea of using something other than electricity to make binary computations? Well, a team at Stanford University has. They’re using tiny droplets of water and bar magnets to make logic gates.

Their goal is not to manipulate information or to compete with modern ‘electrical’ computers. Instead, they’re aiming to manipulate matter in a logical way. Water droplets are like little bags that can carry an assortment of other molecules making the applications far reaching. In biology for instance, information is exchanged via Action Potentials – which are electrical and chemical spikes. We have the electrical part down. This technology could lead to harnessing the chemical part as well.

Be sure to check out the video below, as they explain their “water computer” in more detail.

Continue reading “Manipulating Matter In A Digital Way” →

Astronaut Or Astronot: Amazingly Engineered

June 26, 2015 by 32 Comments

The latest round of community voting in The Hackaday Prize asked a simple question: which project is most likely to save the planet? The results will be posted on Monday.

Now it’s time to see if we’re giving away a $1000 gift card to the Hackaday Store, or just some prizes to people who have voted. The rules here are simple: I’m randomly selecting one person on Hackaday.io. if and only if that person has voted in the latest round of community voting, they get a thousand dollar gift card to the Hackaday store. If the randomly selected person did not vote, I select three people who have voted in the latest round of community voting. For the last few weeks, we’ve been giving out t-shirts. To sweeten the deal, we’re giving away a SmartMatrix, A Simon Says kit, and an Analog Stepper gauge to three people, just because they’ve voted.

Here’s the video:

https://www.youtube.com/watch?v=etBVxy9SvmY

Drat, the Hacker number randomly selected for the $1000 gift card hadn’t voted! Oh what could have been. Don’t let this happen to you next week, VOTE!

To soften the bitterness of defeat we dole out a few awesome prizes to those who had. [xanatos333] gets the Simon Says kit, [sylph.ds] gets an Analog Stepper Gauge, and [dougmsbbs] gets a Smartmatrix. Thanks to those who voted, and be sure to vote in the next round:

NEW ROUND OF VOTING

We’ll have to do some math and run a few scripts to figure out which projects the Hackaday.io community deemed most likely to save the planet. Until we put that data together, it’s time to start a new round of voting. This week, we’re looking for projects that are Amazingly Engineered.

Next Friday we’ll select a random person on Hackaday.io, and if they have voted, they get a $1000 gift card! For the apathetic non-voters… nada.