Hackaday Links: December 18, 2016

December 18, 2016 by Brian Benchoff 13 Comments

You can fly a brick if it has offset mass and you can fly a microwave because it breaks the law of the conservation of momentum. A paper on the EM Drive was recently published by the Eagleworks team, and the results basically say, ‘if this works, it’s a terrible thruster that shouldn’t work’. Experts have weighed in, but now we might not have to wait for another test in the Eagleworks lab: China will fly an EM Drive on their space station. Will it work? Who knows.

The ESP32 is just now landing on workbenches around the globe, and already a few people are diving into promiscuous mode and WiFi packet injection.

The Large Hadron Collider is the most advanced piece of scientific apparatus ever built. It produces tons of data, and classifying this data is a challenge. The best pattern recognition unit is between your ears, so CERN is crowdsourcing the categorization of LHC data.

Holy crap this is cyberpunk. [SexyCyborg] created a makeup palette pen testing device thing out of a Rasberry Pi and a few bits and bobs sitting around in a parts drawer. The project is cool, but the photolog of the finished project is awesome. It’s exactly what you would use to break into the Weyland-Yutani database while evading government operatives on the rooftops of Kowloon Walled City before escaping via grappling hook shot into the belly of a spaceplane taking off.

The Mini NES is Nintendo’s most successful hardware offering since the N64. This tiny device, importantly packaged in a minified retro NES enclosure, is out of stock everywhere. That doesn’t matter because now there’s a mini Genesis. The cool kids had a Genesis. You want to be a cool kid, right? Mortal Kombat was better on the Genesis.

The Arduino (what once was two is again one) launched a new vowel-hating model: MKRZero. The narrow board is powered by USB or LiPo, centers around an Atmel SAMD21 Cortex-M0+ chip, and sports both an I2C breakout header and a microSD card slot. Just watch those levels as these pins are not 5v tolerant.

The American Association for the Advancement of Science is holding a Scientific Maker Exhibit during its annual meeting. This type of exhibit isn’t a poster or presentation — it’s just some table space and a chance to show off a 3D printed apparatus, a new type of sensor, equipment, or some other physical thing. Details in this PDF. This is actually cooler than it sounds, and a significant departure from the traditional poster or presentation found at every other scientific conference.

Did you know Hackaday has a retro edition made specifically for old computers connected to the Internet? That’s my baby, and it’s time for a refresh. If you have any feature requests you’d like to see, leave a note in the comments.

Retrotechtacular: Rocket Sleds

December 18, 2016 by Elliot Williams 28 Comments

If you need to test rockets, missiles, or ejection-seat systems, your first instinct would be to shoot them up in the air and see what happens. But if you want data, film footage, or the ability to simply walk away from a test, you might consider running your experiment on a rocket sled.

The Holloman High Speed Test Track is a 15 km long stretch of meticulously straight railroad track located in the middle of the New Mexico desert, and bristling with measurement equipment. Today’s Retrotechtacular video (embedded below) gives you the guided tour. And by the way, the elderly colonel who narrates? He doesn’t just run the joint — he was one of the human test subjects put on a rocket sled to test the effects of high acceleration on humans. You can see him survive a run around 1:00 in. Continue reading “Retrotechtacular: Rocket Sleds” →

Retrotechtacular: The Aerolux Light Corporation

December 16, 2016 by Lewin Day 38 Comments

The humble incandescent lightbulb is an invention just about anyone born in the 20th Century is more than familiar with. But it’s not the be all and end all of lighting technology – there are neon lights, compact fluorescent bulbs, and even LEDs are finally being adopted for interior lighting. But with the endless march forward, there are vintage throwbacks to the past – how many hipster cafes have you been to lately with great big industrial-looking filament bulbs hanging from the ceiling?

Even when switched off, they have a striking appearance.

However, that’s not all history has to give us. These gas discharge bulbs from yesteryear are absolute works of art.

The bulbs contain delicate floral sculptures in metal, coated with phosphor, and the bulbs are filled with neon or argon gas. Applying mains voltage to the electrodes inside the bulb causes the phospor to fluoresce, creating a glowing flower that is hauntingly beautiful.

These bulbs were manufactured by the Aerolux Light Company, from the 1930s to the 1970s. Once upon a time, they could be had for as little as 20 cents a bulb – nowadays you’re likely to pay over $50 on eBay or Etsy. The bulbs work by the glow discharge effect, not at all dissimilar to garden variety neon lamps.

While it’s not easy, it is possible to make your own vacuum tubes. Maybe it’s time to order some phospor powder and a tank of neon and get to work? Be sure to document your attempt on Hackaday.io.

Thanks to [Itay Ramot] for the tip!

Detecting Water With And Without Headaches

December 15, 2016 by Al Williams 36 Comments

In Texas — at least around Houston — we don’t have basements. We do, however, have bilges. Both of these are subject to taking on water when no one is paying attention. A friend of mine asked me what I thought of an Instructable that showed how to make a water sensor using a few discrete components. The circuit would probably work — it relied on the conductivity of most water to supply enough current to a bipolar transistor’s base to turn it on.

It is easy to overthink something like this, so I told my friend he should go with something a little more old-fashioned. I don’t know the origin of it, but it is older than I am. You can make a perfectly good water detector with things you probably already have around the house. My point isn’t that you should (or shouldn’t) construct a homemade water sensor. My point is that you don’t always need to go to the high-tech solution.

Continue reading “Detecting Water With And Without Headaches” →

Chris Conlon: Device Security 101

December 14, 2016 by Elliot Williams 10 Comments

We all wring our hands over the security (or lack thereof!) of our myriad smart devices. If you haven’t had your home network hacked through your toaster, or baby cam, you’re missing out on the zeitgeist. But it doesn’t have to be this way — smart devices can be designed with security in mind, and [Chris Conlon] came to Pasadena to give us a talk on the basics.

He starts off the talk with three broad conceptual realms of data security: data in transit, data at rest on the device, and the firmware and how it’s updated. A common thread underlying all of this is cryptography, and he devotes the last section of his talk to getting that right. So if you’d like a whirlwind tour of device security, watch on!

Continue reading “Chris Conlon: Device Security 101” →

Ask Hackaday: Dude, Where’s My MOSFET?

December 13, 2016 by Elliot Williams 126 Comments

(Bipolar Junction) Transistors versus MOSFETs: both have their obvious niches. FETs are great for relatively high power applications because they have such a low on-resistance, but transistors are often easier to drive from low voltage microcontrollers because all they require is a current. It’s uncanny, though, how often we find ourselves in the middle between these extremes. What we’d really love is a part that has the virtues of both.

The ask in today’s Ask Hackaday is for your favorite part that fills a particular gap: a MOSFET device that’s able to move a handful of amps of low-voltage current without losing too much to heat, that is still drivable from a 3.3 V microcontroller, with bonus points for PWM ability at a frequency above human hearing. Imagine driving a moderately robust small DC robot motor forwards with a microcontroller, all running on a LiPo — a simple application that doesn’t need a full motor driver IC, but requires a high-efficiency, moderate current, and low-voltage-logic compatible transistor. If you’ve been here and done that, what did you use?

Continue reading “Ask Hackaday: Dude, Where’s My MOSFET?” →

My Beef With Ham Radio

December 12, 2016 by Dan Maloney 373 Comments

My amateur radio journey began back in the mid-1970s. I was about 12 at the time, with an interest in electronics that baffled my parents. With little to guide me and fear for my life as I routinely explored the innards of the TVs and radios in the house, they turned to the kindly older gentleman across the street from us, Mr. Brown. He had the traditional calling card of the suburban ham — a gigantic beam antenna on a 60′ mast in the backyard – so they figured he could act as a mentor to me.

Mr. Brown taught me a lot about electronics, and very nearly got me far enough along to take the test for my Novice class license. But I lost interest, probably because I was an adolescent male and didn’t figure a ham ticket would improve my chances with the young ladies. My ham ambitions remained well below the surface as life happened over the next 40 or so years. But as my circumstances changed, the idea of working the airwaves resurfaced, and in 2015 I finally took the plunge and earned my General class license.

The next part of my ham story is all-too-familiar these days: I haven’t done a damn thing with my license. Oh, sure, I bought a couple of Baofeng and Wouxun handy-talkies and lurked on the local repeaters. I even bought a good, solid HF rig and built some antennas, but I’ve made a grand total of one QSO — a brief chat with a ham in Texas from my old home in Connecticut on the 10-meter band. That’s it.

Continue reading “My Beef With Ham Radio” →