FCC Locks Down Router Firmware

February 26, 2016 by 112 Comments

For years, we have been graced with consumer electronics that run some form of Linux, have a serial port on the circuit board somewhere, and are able to be upgraded through official and unofficial means. That digital picture frame you got for Christmas in 2007 and forgot to regift in 2008? That’s a computer, and it would make a wonderful Twitter feed display. Your old Linksys WRT54G router? You can make a robotic lawnmower out of that thing. The ability to modify the firmware of consumer electronics is the cornerstone of Hackaday’s editorial prerogative. Now that right we have all enjoyed is in jeopardy, thanks to regulations from the FCC and laziness from router manufacturers.
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The New Heathkit Strikes Again

February 26, 2016 by 57 Comments

Alright, this is getting embarrassing.

The rebooted Heathkit has added another kit to its offerings. This time it’s an inexplicably simple and exorbitantly priced antenna for the 2-meter band. It joins their equally bizarre and pricey AM radio kit in the new product lineup, and frankly we’re just baffled by the whole affair.

About the most charitable thing you can say about their “Pipetenna” is that it’ll probably work really well. Heathkit throws some impedance and SWR charts on the website, and the numbers look pretty good. Although Heathkit doesn’t divulge the design within the “waterproof – yes, waterproof!” housing, at 6 dBi gain and only five feet long, we’re going to guess this is basically a Slim Jim antenna stuffed in a housing made of Schedule 40 PVC tubing. About the only “high-end” component we can see is the N-type coax connector, but that just means most hams will need and adapter for their more standard PL-259 terminated coax.

Regardless of design, it’s hard to imagine how Heathkit could stuff enough technology into this antenna to justify the $149 price. Hams have been building antennas like these forever from bits and pieces of wire lying around. Even if you bought all new components, including the PVC pipe and fittings, you’d be hard pressed to put $50 into a homebrew version that’ll likely perform just as well.

The icing on this questionable cake, though, is the sales copy on the web page. The “wall of text” formatting, the overuse of superlatives, and the cutesy asides and quips remind us of the old DAK Industries ads that hawked cheap import electronics as the latest and greatest must-have device. There’s just something unseemly going on here, and it doesn’t befit a brand with the reputation of Heathkit.

When we reviewed Heathkit’s AM radio kit launch back in December, we questioned where the company would go next. It looks like we might have an answer now, and it appears to be “nowhere good.”

Adding Spice To Your Workbench

February 26, 2016 by 43 Comments

Most of us didn’t fight in World War II, drive a race car, or fly the Space Shuttle. But with simulation, you can experience at least some of what it would be like to do those things. Granted, playing Call of Duty isn’t really the same as going to war. No matter what you are simulating, it only goes so far. However, you can get a lot of value from a simulation. I’d bet the average kid who has played Call of Duty knows more about WWII locales and weapons than my high school history teacher.

When it comes to electronics, simulation is an excellent way to get insight into a circuit’s operation. After all, most circuits operate in the abstract–you can’t look at an audio amplifier and see how it works without a tool like a scope. So simulation, when done well, can be very satisfying. You just have to be careful to remember that it isn’t always as good as the real thing.

That’s Spicy

One of the best-known electronics simulators is Spice, which Berkeley created in 1973. In its original form, you had to punch cards that described your circuit and the analysis you wanted to perform. Modern PC versions sometimes replace the deck of cards with a text file. The best modern versions, though, give you a GUI that allows you to draw a schematic and then probe it to see the results.

There are several paid and free versions of Spice (and other simulators) that include a GUI. One of the best for a casual user is the free offering from Linear Technology called LTSpice.

Linear makes LTSpice available and populates it with models for their devices in the hopes you’ll buy components from them. However, the software is entirely usable for anything, and it has a powerful set of features. Linear produces the software for Windows, but I can attest that it runs just fine under Wine on Linux. The Web site will invite you to register, but you don’t have to if you don’t want to.

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Passive WiFi On Microwatts

February 26, 2016 by 30 Comments

A lot of you use WiFi for your Internet of Things devices, but that pretty much rules out a battery-powered deployment because WiFi devices use a lot of juice. Until now. Researchers at the University of Washington have developed a passive WiFi implementation that uses only microwatts per device.

Working essentially like backscatter RFID tags do, each node has a WiFi antenna that can be switched to either reflect or absorb 2.4 GHz radiation. Your cell phone, or any other WiFi device, responds to this backscattered signal. All that’s missing is a nice steady signal to reflect.

passive_wifi-shot0008A single, plugged-in unit provides this carrier wave for multiple WiFi sensor nodes. And here’s the very clever part of the research: to keep the carrier from overwhelming the tiny modulated signal that’s coming from the devices, the plugged-in unit transmits off the desired frequency and the battery-powered units modulate that at just the right difference frequency so that the resulting (mixed) frequency is in the desired WiFi band.

If you’re a radio freak, you’ll recognize the WiFi node’s action being just like a frequency mixer. That’s what the researchers (slightly mysteriously) refer to as the splitting of the analog transmission stage from the digital. The plugged-in unit transmits the carrier, and the low-power nodes do the mixing. It’s like a traditional radio transmitter, but distributed. Very cool.

There’s a bunch more details to making this system work with consumer WiFi, as you’d imagine. The powered stations are responsible for insuring that there’s no collision, for instance. All of these details are very nicely explained in this paper (PDF). If you’re interested in doing something similar, you absolutely need to give it a read. This idea will surely work at lower frequencies, and we’re trying to think of a reason to use this distributed transmitter idea for our own purposes.

And in case you think that all of this RFID stuff is “not a hack”, we’ll remind you that (near-field) RFID tags have been made with just an ATtiny or with discrete logic chips. The remotely-powered backscatter idea expands the universe of applications.

Thanks [Ivan] for the tip!

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Samsung ARTIK Dev Boards Start To Ship

February 26, 2016 by 23 Comments

Another week’s news, another single board computer aimed at Internet of Things applications is launched. This time it’s Samsung’s Artik 5, a platform they’ve been talking about for a while now but which you can now buy as a dev board from Digi-Key for $99.99. For that you get Wi-Fi, Bluetooth and Zigbee connectivity, a dual-core ARM Cortex A7 running at 1GHz, 512MB of memory, and 4GB of eMMC storage. There are the usual plethora of interfaces: GPIO, I2C, SPI, UART, SDIO, USB 2.0, JTAG, and analogue.

The single board computer marketplace is starting to look rather crowded, and with so many competitors to choose from at more reasonable prices you might ask yourself why the ARTIK could be of interest to a maker. And given that Samsung are positioning it in their literature on its increased security for use in commercial  applications such as IoT hubs, IP cameras and industrial and commercial lighting systems, you’d probably be on to something. If you were to make a very rough analogy with the Raspberry Pi range this has more in common with the Compute Module when it comes to intended marketplace than it does with the Pi Zero.

One answer to that question though could be that it is one of the first devices to support the Thread networking protocol for IoT devices. Thread is a collaboration between Google and a range of other interested parties that has been designed to deliver reliable and secure mesh networking for IoT devices in connected homes. As with all new connectivity protocols only time will tell whether Thread is the Next Big Thing, but it is interesting to note in this board nevertheless.

The ARTIK hasn’t made many waves as yet, though we covered the story when it was announced last year. It is worth mentioning that the ARTIK 5 is only the first of three platforms, the ARTIK 1 will be a tiny board with Bluetooth LE aimed at portable and wearable applications while the ARTIK 10 will be an octo-core powerhouse aimed at mulitmedia processing and network storage applications.

Variable Stiffness Joints For Robots And More

February 25, 2016 by 10 Comments

The human body has many miraculous capabilities that we often take for granted. One of the more subtle ones is the variable stiffness of your joints. In technical terms, stiffness refers to the ability to resist a load. Delicately manipulating an artist’s paint brush, for example, doesn’t require much load resistance, but does require fine control. However, that same artist might pick up a bowling ball with a stiffer joint (and, usually, less fine control).

[Christopher Churchill] and some colleagues have a novel mechanical device that can rapidly change stiffness. The device could have applications in robotics and other devices. It can also transmit or attenuate vibration since non-stiff joints don’t pass vibrations as easily as stiff ones.

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Oak Lamp Glows Bright

February 25, 2016 by 29 Comments

Looking for a way to spruce up your place with a touch of rustic-future-deco? Why not embed LEDs somewhere they were never designed for? [Callosciurini] had a nice chunk of oak and decided to turn it into a lamp.

He was inspired by a similar lamp that retails for over $1,000, so he figured he would make his own instead (business idea people?). The oak is a solid chunk measuring 40x40x45cm and what he did was route out an angled channel across all faces of the cube. This allowed him to installed a simple LED strip inside the groove — then he filled it with an epoxy/paint mix to give it that milky glow.

To finish it off he sanded the entire thing multiple times, oiled the wood, and sanded it again with a very fine grit. The result is pretty awesome.

Now imagine what you could do design-wise if you could fold wood to make a lamp? Well with this custom wood-folding saw-blade, the sky is the limit!

[via r/DIY]