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Pagaré smartstrap could give Pebble Time watches contactless payment

Liliputing - 4 hours 7 minก่อน

As promised a few months ago, the folks at FitPay and ConnecteDevice have launched a Crowdfunding campaign for a smart wrist strap that will let you use a Pebble Time smartwatch for mobile payments. The strap is called Pagaré, and it’s eventually expected to sell for $89, but backers of the Kickstarter campaign can request one […]

Pagaré smartstrap could give Pebble Time watches contactless payment is a post from: Liliputing

The Internet of Broken Things (or, Why am I so Cold?)

Hackaday - 4 hours 57 minก่อน

Although the Internet of Things (IoT) is a reasonably new term, the idea isn’t really all that new. Many engineers and hackers have created networked embedded systems for many years. So what’s different? Two things: the Internet is everywhere and the use of connected embedded systems in a consumer setting.

The Philips Hue light bulb

Like anything else, there’s a spectrum of usefulness to IoT. Watching The Expanse, the other day (which is not a bad show, by the way), I noticed that if you had the right IoT lights, you could run an app that would change your lighting to suit the show in real-time. I don’t have those lights, but I suppose when you the action moves to a dark sub-basement, your lights dim and when you are in a space ship’s reactor room, the turn red, and so on. Fun, but hardly useful or life-changing.

On the other hand, there are some very practical IoT items like the Nest thermostat. It might seem lazy to want to monitor and control your thermostat from your tablet, but if you are frequently away from home, or you have multiple houses, it can be a real positive to be able to control things remotely. With the recent blizzard on the U.S. east coast, for example, it would be great to turn on the heat in your weekend cottage 150 miles away while you were still at work or home. However, the Nest recently had a hiccup during an upgrade and it has made many of their customers mad (and cold). I’ll get back to that, in a minute. First, I want to talk about the problems with deploying something that will be in many varied environments (like people’s homes) that controls something real.

Good Intentions

Problems arise, though, when you consider that programmers (and sometimes hardware guys) are relatively optimistic. How many times has a Windows update broken something on your computer? Linux used to be better, but lately, I dread updates, especially major ones because they sometimes will stop my machine from even booting, triggering a big debugging session. The Mac, I’m told, has had similar upgrade horror stories.

In the old days, a bad update to a piece of software meant, perhaps, that payroll checks wouldn’t go out on time. That’s a disaster for some people, of course, but it is a survivable one. Maybe you couldn’t get e-mail for a few hours. You’ll live. Once you start connecting to the real world, though, things get more complicated and riskier.

Chip on a Bus Modems connected the IoT before the Internet was in everyone’s homes.

We all have stories where our assumptions during development don’t match up with reality. Years ago, I developed a system that had three boxes, one at a central station and two remote boxes. Periodically (or on command) the remote boxes would call the central one using some modems (this was definitely a few years ago) and send their data.

The system worked great on my bench, and I sent a team 500 miles away to install them. One of the remote boxes was very remote, indeed, and sat on a newly set phone pole in the middle of a swamp. The installer called me from that very phone line to tell me the system didn’t work. I was surprised, to say the least. I knew the phone line had two circuits, and he was using a field phone to call me from the secondary line, so I asked him to trigger a call and hold the phone up to the box.

I heard the dial tone I expected. Then I heard a series of TouchTones. Then I still heard the dial tone. It hit me: the phone line in the middle of the swamp didn’t have TouchTone dialing (and couldn’t have it)! The EPROM that controlled the dialing had the string ATDT in it, where the last T was for tone dialing. It needed to have ATDP (for pulse dialing). A quick fix except, in those days, the only way to get that to them quickly was to put it on a bus.

My point is, when you deploy to strange places in the real world, your assumptions get tested. Sometimes tested hard.

Safety Dance

If you work on systems that are known to be dangerous (like weapons or airplanes), there is a lot of effort to make absolutely sure that things work the way you expect. This goes for updates, too. You can’t just make a change, do a quick test and send it out into the field. Even so, sometimes bad things get out.

Even if your system works great in the lab (like mine did), you can still get unexpected problems during installation or just the environment (like my phone line). Airbus found that out the hard way last year.

Getting development right isn’t the only thing when you are rolling out IoT systems. You have to test, of course. But you also need to test over a broad range of environments and circumstances. Even then, you won’t get them all. You need to think about how to do updates in the way that is least likely to break. It is acceptable to roll back to the original version of things, but it is not acceptable to break during an update.

Security Dance

Then there’s security. If you can update something in the field–especially over the network–how can you be sure an update is legitimate and not an attack. Digital signatures, encryption, and other techniques can do that, but how many of us worry about things like that.

Updating your copy of a new video game isn’t that big of a deal. However, depending on the operating system, a rogue update could, in theory, go off and steal your credit card numbers or passwords. Or it could install a Trojan horse that puts your computer on a botnet that sends spam and attacks other computers.

That’s bad enough. What happens when that software update controls your washing machine which now spews water out in the middle of the night so your house floods? Or your dryer overheats and catches on fire?

As end users, we have a vested interest in knowing our IoT devices are safe, even after an update. We also should worry that the update is legitimate.

Empty Nest The Nest thermostat could be the most useful IoT device so far

If you think this is overblown, think again. I mentioned the Nest earlier (that we saw rooted a few years ago, by the way). A recent software update caused thermostats to run their batteries down in some cases, requiring a restart or even a recharge to get them back in service. This isn’t a theoretical problem. It affected many users who woke up to cold houses. People who could not easily get to a remote thermostat were especially peeved.

If you are feeling smug because you have a custom non-IoT thermostat built around an Arduino, don’t. If you have a car with a modern keyless entry system, there are vulnerabilities there, too. If you see someone getting their car keys out of the freezer, you’ll know they read about that. Granted, that’s not a bug, it is a criminal attack, but it points out that IoT is opening the door to many unintended consequences.

The Nest case isn’t the first (nor will it be the last) of an IoT update breaking something. As developers, we have to think beyond our workbench when deploying systems or software. The wider the deployment, the harder you have to think about all the cases, all the chances for exploits, and how to recover when it happens. The alternative is going to be government regulation like certain industries already have. The cost of getting things right will pale in comparison to complying with strict regulation from a government agency.

Filed under: rants

Deals of the Day (2-08-2016)

Liliputing - จันทร์, 02/08/2016 - 23:57

Amazon’s continuing to offer its entry-level Fire tablet for $40 as part of its Amazon Device Deals which kicked off this weekend. But if you’re looking for something a little more laptop-like, Microsoft’s got you covered. The Microsoft Store is running a President’s Day Sale with some massive price cuts on Windows notebooks and tablets. Some of the best […]

Deals of the Day (2-08-2016) is a post from: Liliputing

Get Your Hackaday Belgrade Tickets Now

Hackaday - จันทร์, 02/08/2016 - 23:31

We have just opened up registration for Hackaday | Belgrade — a hardware conference on April 9th. Get your ticket now and make arrangements to visit Belgrade this Spring. Tickets are inexpensive, travel costs from other parts of Europe are very reasonable, the weather will be beautiful, and the all-day madness that we have planned will make you wish it were a week instead of just sixteen hours. These tickets will sell out so please share this post with your friends so they are not left ticketless.

Packed with Amazing People If you don’t recognize the name you will almost certainly recognize his internet persona: Mike’s Electric Stuff. He’s been regularly featured on the front page of Hackaday as he churns out a unique body of work like tearing down Flir’s low-end gear to discover it’s identical to their high-end offerings.

Hackaday is a global community and that is what makes Hackaday | Belgrade spectacular. We are still accepting proposals for talks through February 15th but haven’t yet made all of the decisions regarding presenters — you should submit a proposal! We’ll publish an article about all of the presenters once we have wrapped up the call for proposals. Expect to hear back about this around February 22nd.

One thing I am very excited about is that Mike Harrison will be at the conference. His talk will cover his exploration of an absurdly expensive and complicated relic which was used in the 1950’s for large-format video projection. Mike’s ability to unlock understanding of complex (and awesome) electronics is quite amazing; this talk is not to be missed. But Mike is just one of a dozen presenters from all over Europe. Several members of the Hackaday crew will be on hand and the venue will be packed with hundreds of fellow hardware hackers. You won’t want to miss this.

You Will Hack This Badge

This is the first Hackaday event where we have an active electronic badge. Voja Antonic has been hard at work with the design and just published the first details a few days ago.

The central feature of the badge is an 8×16 LED matrix driven by a PIC microcontroller. It’s running a USB bootloader which will let you flash your own custom code without needing a programmer. We were speaking with some of our friends over at Microchip regarding the bootloader and they offered to supply all the microcontrollers for the badge, an offer we were happy to accept.

Voja has already programmed the first demo application seen here, it’s Tetris written in assembly language. Impressive!

We were overwhelmed by the popularity of badge hacking at the Hackaday SuperConference last November. You can bet that badge hacking will be one of the most popular activities at Hackaday Belgrade. I have written a hardware emulator to work on some animations. It uses the SDL2 library to display the LED matrix and take three button inputs (the final badge design will have four buttons arranged in up/down/left/right configuration). Our hope is to host a demoscene competition that is open to anyone, whether you can attend the conference or not. More on that later.

Live Music on Two Stages

As the evening sets in and the talks wind down, we have lined up bands and DJs to take the stage and carry us well into night. You won’t have to stop the badge hacking or anything else that you’re into, but you won’t have to solder in silence either.

As you can tell, this conference goes way beyond talks. This is hardware culture and you’ve just got to be there. Running from 10am until 2am, there’s more than enough to keep you occupied for one day. But make sure to hang out on the event page to get inside information on other non-formalized social events that will happen the night before and the day after. See you in Belgrade!

Filed under: cons, Hackaday Columns

Google Plastic? Report says Google is working on a new VR headset for smartphones

Liliputing - จันทร์, 02/08/2016 - 22:22

This year we’re expecting powerful, expensive virtual reality devices like the Oculus Rift, HTC Vive, and Sony PlayStation VR to hit the streets. But Google started to bring VR experiences into the mainstream nearly two years ago by introducing Google Cardboard: a cheap, DIY headset that uses your smartphone as a screen. Now the Financial […]

Google Plastic? Report says Google is working on a new VR headset for smartphones is a post from: Liliputing

The Coming Age of 3D Integrated Circuits

Hackaday - จันทร์, 02/08/2016 - 22:01

The pedagogical model of the integrated circuit goes something like this: take a silicone wafer, etch out a few wells, dope some of the silicon with phosphorous, mask some of the chip off, dope some more silicon with boron, and lay down some metal in between everything. That’s an extraordinarily basic model of how the modern semiconductor plant works, but it’s not terribly inaccurate. The conclusion anyone would make after learning this is that chips are inherently three-dimensional devices. But the layers are exceedingly small, and the overall thickness of the active layers of a chip are thinner than a human hair. A bit of study and thought and you’ll realize the structure of an integrated circuit really isn’t in three dimensions.

Recently, rumors and educated guesses coming from silicon insiders have pointed towards true three-dimensional chips as the future of the industry. These chips aren’t a few layers thick like the example above. Instead of just a few dozen layers, 100 or more layers of transistors will be crammed into a single piece of silicon. The reasons for this transition range from shortening the distance signals must travel, reducing resistance (and therefore heat), and optimizing performance and power in a single design.

The ideas that are influencing the current generation of three-dimensional chips aren’t new; these concepts have been around since the beginnings of the semiconductor industry. What is new is how these devices will eventually make it to market, the challenges currently being faced at Intel and other semiconductor companies, and what it will mean for a generation of chips several years down the road.

The History of 3D Chips Many different circuits on the same die, tied together with three-dimensional interconnects. Image source: Pavlidis & Friedman, Three-dimensional Integrated Circuit Design (2010)

In the late 1960s and early 1970s, chips became increasingly complex. The forefront of semiconductor technology moved from op-amps and small digital packages to semiconductors with thousands of transistors, and with this came in increasing reliance on interconnects between different portions of these chips.

In the march of technology over the past fifty years, transistors have gone from something you can see with the human eye to tiny specks only a few atoms wide. Interconnects become the dominant design choice, especially with ever-increasing complexity of designs, increasing bus width, and more numerous inputs and outputs.

Because all but the most basic integrated circuits are inherently three-dimensional, the obvious choice for where to put these interconnects was the same solution in any sprawling metropolis; if you can’t grow out, grow up.

This line of research continued throughout the 1970s, 1980s, and 1990s as an academic pursuit, with solutions to new problems. How do you cool the inside of a cube? You can put cooling channels throughout the entire chip. While these problems were simple to define, and the solutions easy to explain, taking the entire idea through manufacturing to a finished product was hard. A much easier way to increase transistor density was to stack individual packages on top of each other.

The main chip on the Raspberry Pi Zero is actually two ICs. The bottom is the ARM processor, while the top is the DRAM. This is known as a Package on Package (POP) assembly.

These Package on Package devices can be seen – albeit at an oblique angle – on dozens of devices. The large chip on the Raspberry Pi Zero, Model A, and Model B are POP devices, with the RAM on the top chip connected directly to the Broadcom CPU. The latest, highest capacity RAM modules also use this technique. The JEDEC standards for memory don’t account for 16GB DDR3 modules, but that doesn’t mean you can’t buy them. Here, again, PoP devices are how companies are getting around the problems of interconnects.

The Current State of 3D Chips

Samsung’s V-NAND [image source]While the idea of 3D chips constructed out of multiple layers of silicon is an old idea, only recently have we seen this sort of technology make it into consumer devices. In 2013, Samsung moved into the 3D Flash market with V-NAND, regarded as the first true production-grade 3D transistor technology.

Chipworks did a terrific teardown of Samsung’s V-NAND found in Samsung’s 850 Pro SSDs. It is, by any measure, an incredible feat of engineering. The V-NAND stack found in these SSDs are a 38-layer sandwich of transistors, with each transistor holding one bit of information.

This innovation obviously allows Samsung to put more transistors into a small area, leading to higher capacities. If you believe the Samsung marketing material, up to 100 layers of transistors can be stuffed onto a chip, paving the way for very, very high-capacity drives. This capacity isn’t the only benefit; thanks to the construction of V-NAND, interference between memory cells is reduced, making the drive more power efficient. Write endurance – the number of times a memory cell can be written to without going bad – is improved over normal 2D NAND Flash.

Even if most of the claims about Samsung’s V-NAND 3D Flash technology are marketing wank, you can’t deny it’s a very good SSD. Look on any ‘build suggestion’ thread in the forums of any PC-based community, and you’ll find a Samsung 850 Pro SSD somewhere in the parts list. 3D Flash is a technological triumph and a market success. The question on everyone’s mind then becomes ‘when is it going to be more than just SSDs?’

The next generation of Nvidia GPUs, Volta, will feature stacked DRAM when it is released in 2018. While this is about the same level of complexity as stacked NAND Flash, it does tell us that 3D chips are hitting the mainstream, and it’s only a matter of time before we can think of a CPU as a true 3D device, and not just a few layers placed on top of each other.


If you trace the origins of interesting technological achievements in semiconductors, the usual progression begins with universities, moves into production with memories, and finally becomes part of the glue that holds CPUs together. At one time, Intel was best known for their very high-capacity DRAM chips (hundreds of bytes!), before the knowledge gained in their manufacture moved over to CPUs.

Intel’s EMIB. [image source]This inevitably means CPUs designed with dozens of layers. For Intel, the next big advancement is the Embedded Multi-die Interconnect Bridge (EMIB), that takes the PoP concept, strips it of epoxy, and does everything at a much lower level. The EMIB is effectively a backplane between dies. By putting multiple dies on a single piece of silicon, with vias tunneling in a zigzag fashion, Intel can put many different circuits on a single piece of silicon.

While putting multiple dies on a single piece of silicon will be a boon for Intel – especially with the Altera IP in their portfolio – it’s not exactly a true three-dimensional chip. That will have to wait a while; we’ve only had 3D Flash for a few years now, and 3D RAM won’t be public for another two years. Making a 3D CPU is a much more complex engineering challenge, and for that we may be waiting the better part of a decade.

Three dimensional chips will be released, though. It’s only a matter of time. There’s simply no other way to increase the density of interconnects, the number of devices on a chip, or speed than by moving into a third dimension of silicon.

Filed under: Featured

A Wireless Wood Stove Monitor

Hackaday - จันทร์, 02/08/2016 - 19:00

[Michel] has a wood stove in his basement for extra heat in the winter. While this is a nice secondary heat source, he has creosote buildup in the chimney to worry about. [Michel] knows that by carefully monitoring the temperature of the gases in the chimney, he can hit the sweet spot where his fire burns hot enough to keep the creosote under control and cool enough that it doesn’t burn down the house. To that end, he built a wireless wood stove monitor.

The first version he built involved an annoying 20 foot run between the basement and living room. Also, the thermocouple was mounted on the surface and made poor contact with the chimney. Wood Stove Monitor 2.0 uses a probe thermometer on an Exhaust Gas Temperature (EGT) thermocouple to measure the temperatures. The intel is fed to a thermocouple amplifier to provide a cold-compensation reference. This is shielded so that radiant heat from the stove doesn’t compromise the readings. An nRF24L01+ in the basement monitoring station communicates with another module sitting in the living room display so [Michel] can easily find out what’s going on downstairs. When it’s all said and done, this monitor will be part of a bigger project to monitor power all over the house.

Interested in using a wood stove to help heat your house? Why not build your own?

Filed under: misc hacks, wireless hacks

Thermaltake Gets On The 3D Printing Bandwagon

Hackaday - จันทร์, 02/08/2016 - 16:00

We’re interested by a move from Thermaltake, a manufacturer of computer cases, fans, and power supplies. Thermaltake has released a computer case designed to be modded by those with a 3D printer. They released a set of models that fits the new case. These are all hosted on a service much like Thingiverse. So if you want a single SSD or a whole rack, print the model. Watercooling? There’s a model for that. In concept, it’s very cool.

We’re not certain how to feel about this. Our initial impression was that if Thermaltake is going to launch a case around 3D printing, they should at lease tune their printer and get some nice prints before they take the press photos. On our second pass we became intrigued. Is this a manufacturer cutting costs, crowd-sourcing design and engineering talent for free, or empowering the user? Arguably, a computer case is a great test bed for this kind of interaction.

Despite out skepticism, we’d like to see more manufacturers take this kind of contributing interest in 3d printing. If only to see where it goes. What other products do you think would benefit from this kind of, print the product you actually want model?

Filed under: 3d Printer hacks, computer hacks

Greased Lightning Shows 360 Degrees

Hackaday - จันทร์, 02/08/2016 - 13:00

A lot of people got drones for Christmas this year (and many Hackaday readers already had one, anyway). A lot of these drones have cameras on them. The expensive ones beam back live video via RF. The cheaper ones just record to an SD card that you can download later.

If you are NASA, of course, this just isn’t good enough. At the Langley Research Center in Virginia, they’ve been building the Greased Lightning (also known as the GL-10) which is a 10-engine tilt-prop unmanned aerial vehicle. The carbon fiber drone is impressive, sure, but what wows is the recent video NASA released (see below).

You can watch the video on your PC but don’t. If you have Google Cardboard, this is what Cardboard was made to do. If you don’t, at least watch it on a phone or a tablet. You’ll be able to look all around (and up and down) just by moving your phone. It makes for an awesome flight video. If you just have to watch it on a desktop, YouTube will show you some controls to let you navigate the view, but it just isn’t the same.

We’ve seen tilt rotors before, but this is way out in front of just about anything we’ve seen before. Even without the airframe, we’d love to have the camera system on our flying bots.

Photo: NASA Langley/David Bowman

Thanks [Scott Anderson] for the tip.

Filed under: drone hacks, slider

Robo Car Via 3G

Hackaday - จันทร์, 02/08/2016 - 10:00

[Emil Kalstø] has a pretty solid remote control car. We don’t mean a little car with a handheld remote you can drive around the neighborhood. [Emil’s] car has a camera and a cell phone so that it can go anywhere there’s 3G or 4G networking available.

The video (see below) shows the results (along with [Emil’s] little brother acting as a safety officer). The video offers tantalizing detail you might find useful if you want to reproduce a similar vehicle. However, it stops short of providing complete details.

The two batteries onboard will power the vehicle for over 20 hours of continuous use. The 30W motor is reduced with a chain drive to go about “walking speed.” There’s a Raspberry Pi with a Huawei 3G USB dongle onboard and [Emil] uses an XBox controller to do the steering from the warmth of his living room. Of course, a Pi can’t handle a big motor like that directly, so a Phidgets USB motor controller does the hard work. The software is written using Node.js.

The camera mount can swivel 230 degrees on a servo so that the operator can scan the road ahead. The video mentions that steering the car required a heavy-duty servo with metal gears (an earlier attempt with nylon gears didn’t work out).

Overall, it looks like a solid build. We hope [Emil] will share code and more details soon. If you can’t wait (and your insurance is paid up), you might have a go at an even bigger car. Surprisingly, there’s more than one example of that.

Filed under: Cellphone Hacks, Raspberry Pi

Hackaday Links: February 7, 2016

Hackaday - จันทร์, 02/08/2016 - 07:00

For a very long time, the original, 11 foot-long on-screen model of the USS Enterprise from Star Trek the original series – “NCC one seven O one. No bloody A, B, C, or D.” – was housed in the Smithsonian’s Air and Space Museum in Washington, DC. Recent visitors may have noticed the Enterprise is no longer on display. It’s being restored by the finest aircraft conservators in the world. There are a few great videos showing off how much goes into restoring a cultural icon.

Last weekend Hackaday visited Sparklecon in Fullerton, CA. This means I was in LA on the last Saturday of the month. What’s so special about that? The W6TRW Swap Meet at Northrop Grumman in Redondo Beach. Here’s the pics from that. The best thing I found? A wooden acoustic coupler modem for $15. Once I told the guys at the booth what it was, the price went up to $20. Still worth it.

What’s the worst thing about modern computers? They’re all LCDs, and that means worse resolution, terrible colorspace, and monitors that are very, veeeerrrrryyyy wide. The consequence of this is a complete and total lack of screen savers. Never fear, because the flying toaster is back, this time as an SD card holder. It’s 3D printable, so if you have some white, silver, and black filament sitting around, you know what to do.

The USB Killer hit the tips line a few times this week for inexplicable reasons. We’ve seen it before, but we haven’t seen it again. Surprisingly, no one – outside a bizarre Indiegogo campaign that shouldn’t exist – has made their own USB killer. Here’s your call to action: build a USB killer, and I’ll test it out.

An SDIP-64 chip compared to a DIP-28 chip. Note the finer lead spacing on the SDIP device.

There’s more variety to your standard DIP-packaged chips than you might expect. The weirdest of these – at least when it comes to perfboard construction – is the SDIP, or Skinny Dual In-line Package. Instead of having a standard 0.1″ pitch between leads, the SDIP has a 0.070″ pitch. [Chuck] was having some problems looking for SDIP to DIP adapters until he found this amazing trick the connector companies don’t want you to know aboutJust plop the chip in at a 45º angle, bend a few pins, and you’re good to go.

Filed under: Hackaday Columns, Hackaday links

Another Use for Old Hard Drive Parts: Anemometer

Hackaday - จันทร์, 02/08/2016 - 04:00

So you’ve just taken apart a hard drive, and you’re looking at all the pieces on your desktop. You’re somehow compelled to use them all in different projects. Why not pull out that very high quality bearing that keeps the platters spinning at high RPMs and build this simple anemometer with it? That’s what [Sergei Bezrukov] did, and it looks like a perfect el cheapo project.

The build is fairly low-tech and entirely sufficient. The cups are made from plastic containers that used to contain pantyhose. A Hall-effect sensor and a magnet take care of measuring the rotations, feeding its signal into a PIC that calculates the wind speed from the revolution rate. The rest of the housing is PVC, with some other miscellaneous parts found at the hardware store.

To calibrate the device, [Sergei] made a second hand-held unit that he could (presumably) drive around in a car to get a baseline wind speed, and then note down the revolution rate. Once you’ve got a good reference, holding the portable unit up to the permanent one transfers the calibration.

But the star of the show, that lets the anemometer spin effortlessly, is the sweet bearing that used to spin a hard-drive platter. If you haven’t played with one of these bearings before, you absolutely should. We just ran a post on taking apart a hard drive for its spare-parts goodness so you have no excuse. If you’re feeling goofy, you can mount one onto a board, step on it with the ball of your foot, and spin. They’re quality bearings, and you’ll be surprised how quickly you can spin as you pull your arms in.

Thank [Matt] for the tip!

Filed under: misc hacks

Repairing Vintage Clock Movements

Hackaday - จันทร์, 02/08/2016 - 01:00

It’s obvious that [Matthew] cares a great deal for vintage electric clocks. He is especially fond of the bedside alarm variety, which in our experience cast a warm orange glow on the numbers and emitted a faint, gentle hum. [Matthew] has written up a thorough treatment of Sunbeam movements in particular that covers identification, disassembly, cleaning, and repair.

These workhorse timepieces are cheap and fairly plentiful if you work the estate sale or thrift store circuit. Sometimes there is a bit of trouble with motor pinions disintegrating or the teeth wearing down on the nylon gears. The decades-old petroleum lubricant combined with heat from the spinning rotor can eat away at the motor pinion, causing it to crumble if disturbed.

Wishing to save some of these clocks from landfills, [Matthew] designed motor pin replacements specifically for Sunbeam electric movements, the relatively  inexpensive alternative that graced many a mid-century household clock. He only had the shaft and a broken original to work with, but was able to design a sturdy acrylic replacement using this involute spur gear builder to generate a DXF file. Then it was just a matter of creating an STL file with Rhino 3D and shipping it off to Shapeways.

If you’ve ever wanted to get into clock or watch repair, this looks like a great way to get your feet wet unless you’re ready for some serious vintage watch repair. There’s no need to reinvent the pinion because [Matthew] sells them through his site. If you have a printer, the STL files await you.

Filed under: clock hacks, how-to

App note: Auto-zero amplifiers ease the design of high-precision circuits

dangerous prototype - จันทร์, 02/08/2016 - 00:00

An application note from Texas Instruments on new chopper amplifers superiority over old design chopper amps. Link here (PDF)

This article shows that the auto-zero calibration technique is very different from the chopper technique and is one that, when implemented through modern process technology, allows the economical manufacturing of wideband, high-precision amplifiers with low output noise.

App note: Auto-zero amplifiers ease the design of high-precision circuits

dangerous prototype - จันทร์, 02/08/2016 - 00:00

An application note from Texas Instruments on new chopper amplifers superiority over old design chopper amps. Link here (PDF)

This article shows that the auto-zero calibration technique is very different from the chopper technique and is one that, when implemented through modern process technology, allows the economical manufacturing of wideband, high-precision amplifiers with low output noise.

App note: Auto-zero amplifiers ease the design of high-precision circuits

dangerous prototype - จันทร์, 02/08/2016 - 00:00

An application note from Texas Instruments on new chopper amplifers superiority over old design chopper amps. Link here (PDF)

This article shows that the auto-zero calibration technique is very different from the chopper technique and is one that, when implemented through modern process technology, allows the economical manufacturing of wideband, high-precision amplifiers with low output noise.

AudioCast M5 is a $37 multi-room audio streamer, Chromecast Audio wannabe

Liliputing - อาทิตย์, 02/07/2016 - 22:15

Last year Google launched a tiny device called the Chromecast Audio that you can plug into any speaker to stream music from your phone or the internet to that speaker. This year Uyesee has introduced a similar device called the AudioCast M5. Like the Chromecast Audio it plugs into any speaker, pairs with an Android or […]

AudioCast M5 is a $37 multi-room audio streamer, Chromecast Audio wannabe is a post from: Liliputing

Graphene Batteries Appear, Results Questionable

Hackaday - อาทิตย์, 02/07/2016 - 22:01

If you listen to the zeitgeist, graphene is the next big thing. It’s the end of the oil industry, the solution to global warming, will feed and clothe millions, cure disease, is the foundation of a space elevator that will allow humanity to venture forth into the galaxy. Graphene makes you more attractive, feel younger, and allows you to win friends and influence people. Needless to say, there’s a little bit of hype surrounding graphene.

With hype comes marketing, and with marketing comes products making dubious claims. The latest of which is graphene batteries from HobbyKing. According to the literature, these lithium polymer battery packs for RC planes and quadcopters, ‘utilize carbon in the battery structure to form a single layer of graphene… The graphene particles for a highly dense compound allowing electrons to flow with less resistance compared to traditional Lipoly battery technologies” These batteries also come packaged in black shrink tubing and have a black battery connector, making them look much cooler than their non-graphene equivalent. That alone will add at least 5mph to the top speed of any RC airplane.

For the last several years, one of the most interesting potential applications for graphene is energy storage. Graphene ultracapacitors are on the horizon, promising incredible charge densities and fast recharge times. Hopefully, in a decade or two, we might see electric cars powered not by traditional lithium batteries, but graphene supercapacitors. They’ll be able to recharge in minutes and drive further, allowing the world to transition away from a fossil fuel-based economy. World peace commences about two weeks after that happens.

No one expected graphene batteries to show up now, though, and especially not from a company whose biggest market is selling parts to people who build their own quadcopters. How do these batteries hold up? According to the first independent review, it’s a good battery, but the graphene is mostly on the label.

[rampman] on the RCgroups forums did a few tests on the first production runs of the battery, and they’re actually quite good. You can pull a lot of amps out of them, they last through a lot of charging cycles, and the packaging – important for something that will be in a crash – is very good. Are these batteries actually using graphene in their chemistry? That’s the unanswered question, isn’t it?

To be fair, the graphene batteries shipped out to reviewers before HobbyKing’s official launch do perform remarkably well. In the interest of fairness, though, these are most certainly not stock ‘graphene’ battery packs. The reviewers probably aren’t shills, but these battery packs are the best HobbyKing can produce, and not necessarily representative of what we can buy.

It’s also doubtful these batteries use a significant amount of graphene in their construction. According to the available research, graphene increases the power and energy density of batteries. The new graphene batteries store about as much energy as the nano-tech batteries that have been around for years, but weigh significantly more. This might be due to the different construction of the battery pack itself, but the graphene battery should be lighter and smaller, not 20 grams heavier and 5 mm thicker.

In the RC world, HobbyKing is known as being ‘good enough’. It’s not the best stuff you can get, but it is cheap. It’s the Wal-Mart of the RC world, and Wal-Mart isn’t introducing bleeding edge technologies that will purportedly save the planet. Is there real graphene in these batteries? We await an in-depth teardown, preferably with an electron microscope, with baited breath.

Filed under: chemistry hacks

Free PCB Sunday: Pick your PCB

dangerous prototype - อาทิตย์, 02/07/2016 - 22:00

We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service. This week two random commenters will get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB. You get unlimited free PCBs now – finish one and we’ll send you another! Don’t forget there’s free PCBs three times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Be sure to use a real e-mail in the address field so we can contact you with the coupon.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.
  • PCBs are scrap and have no value, due to limited supply it is not possible to replace a board lost in the post

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Deals: Amazon Fire for $40, other Fire and Kindle devices on sale too

Liliputing - อาทิตย์, 02/07/2016 - 20:48

Amazon’s entry-level Fire tablet is already probably one of the best tablets you can buy for $50. But for the next week you pick one up for just $40. The company is running an “Amazon Device Deals” sale with discounts on a number of Fire tablets, Kindle eReaders, and bundles that knock between $10 and […]

Deals: Amazon Fire for $40, other Fire and Kindle devices on sale too is a post from: Liliputing

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