“Alexa, Order Everyone In San Diego A Doll House”

Every day it seems there is a new Alexa story in the news, as for the moment the Amazon voice assistant is in the ascendant over its rivals from Google, Apple, and Microsoft. Today’s slice of Alexa weirdness comes courtesy of a newsreader in San Diego, who inadvertently triggered Alexa-enabled devices within hearing distance of a television to buy doll houses when he reported on a Dallas child’s accidental purchase.

It’s unclear whether any doll houses were dispatched or whether the Echos and Dots merely started the process and asked their owners for confirmation, but we hope it serves to draw attention to the risks associated with an always-on and always-listening device. We’ve looked at how the technology has seemingly circumvented the normal privacy concerns of our own community, so it’s hardly surprising that this kind of incident catches the greater public completely unprepared. It’s one thing for the denizens of a hackspace to troll the owner of a Dot by adding embarrassing products to their wish list, but against a less-informed user who hasn’t worked out how to lock down the device’s purchasing abilities, it’s not too far-fetched to imagine a criminal attack.

Voice assistants are clearly going to become a ubiquitous feature of our lives, and it is inevitable that there will be more such unfortunate incidents which will serve to educate the public about their privacy before the technology reaches maturity. This particular story is definitely Not A Hack, though as our “Alexa” tag shows the devices have huge potential to bring a new dimension to our work. It’s up to all of us in our community to ensure that the voice assistant owners in our lives are adequately educated about them, and maybe resist the urge to say “Alexa, add all the Hackaday merchandise to my wish list!”.

CES2017: Dissolvable Support Material

Over the last year, it seems the next big thing in 3D printing is dual and multi-extrusion. This gets you multi-colored objects, but if you have the right filament, it also allows you to print objects that would otherwise be impossible to print. This week, Airwolf 3D announced their HydroFill water soluble support material. They had a few sample prints and a fish tank, and yes this stuff does dissolve in water quickly.

There were a few problems with dissolvable support material in the past. PVA is water soluble, but it doesn’t print well. HIPS can be dissolved in limonene, but the resulting goo is toxic. Airwolf’s HydroFill beats both of these filaments, and the prints compare well to what E3D showed off with their Scaffold filament recently.

Check out my video below where [Jack Licorish] goes over the characteristics of HydroFill.

Continue reading “CES2017: Dissolvable Support Material”

Yes, You Can Reverse Engineer this 74181

[Ken Shirriff] is the gift that keeps on giving this new year. His latest is a reverse engineering of the 74181 Arithmetic Logic Unit (ALU). The great news is that the die image and complexity are both optimized for you to succeed at doing your own reverse engineering.

74181-openedWe have most recently seen [Ken] at work explaining his decapping and reverse engineering process at the Hackaday SuperCon followed soon after by his work on the 8008. That chip is crazy with complexity and a die-ogling noob (like several of us on the Hackaday crew) stands no chance of doing more than simply following along with what he explains. This time around, the 74181 is just right for the curious but not obsessed. Don’t believe me? The 8008 had around 3,500 transistors while the friendly 74181 hosts just 170. We like those odds!

A quick crash course in visually recognizing transistors will have you off to the races. [Ken] also provides reference for more complex devices. But where he really saves the day is in his schematic analysis. See, the traditional ‘textbook’ logic designs have been made faster in this chip and going through his explanation will get you back on track to follow the method behind the die’s madness.

[Ken] took his own photograph of the die. You can see the donor chip above which had its ceramic enclosure shattered with a brisk tap from a sharp chisel.

Disposable Camera Coil Gun!

Some of the most enjoyable projects tend to have the terrible drawback of also having the most potential to cause bodily harm, like getting zapped by the capacitor when digging into a disposable camera. But often — if you’re careful — this curiosity pays off and you wind up learning how to make something cool like this coil gun from a camera flash’s capacitor. This handheld launches a small nail, and is packed in a handheld form factor with a light switch trigger.

[LabRatMatt] dispels any illusions of potential harm upfront and then repeatedly urges caution throughout his detailed guide. He breaks down the physics at work while maintaining a lighthearted tone. This coil gun uses a capacitor and charging circuit ripped from a disposable camera — [LabRatMatt] decided to double up with another capacitor that he had on hand from a previous project. The coil was repurposed from an old doorbell, but make sure to use a few hundred windings if you make your own coil. A light switch ended up being suitable for a trigger since it is able to handle the voltage spikes.

When assembled, it almost looks like something you’d expect to see in a post-apocalyptic wasteland, but it works!

Continue reading “Disposable Camera Coil Gun!”

CES2017: Monoprice Unveils Expanded Line of 3D Printers

At CES last year, Monoprice introduced a $200 3D printer. Initial expectations of this printer were middling. My curiosity got the best of me, and last summer I picked up one of these printers for a review. The Monoprice MP Select Mini is actually phenomenal, and not just ‘phenomenal for the price’. This machine showed the world how good one of the cheapest printers can be. The future is looking awesome.

You might think Monoprice wouldn’t be able to top the success of this great little machine. You would be wrong. This week, Monoprice announced a bevy of new and upgraded printers. Some are resin. Some are huge. One will sell for $150 USD.

Continue reading “CES2017: Monoprice Unveils Expanded Line of 3D Printers”

Whole House HiFi Tamed Without Fuss

One of the problems that has accompanied the advent of ever more complex home entertainment systems is the complexity of the burgeoning stack of remote controls that manifest themselves alongside your system. It doesn’t matter if you have a fancy does-the-lot universal remote, you are still left with a slew of functions to perform before you can sit down to enjoy the music.

[Robert Cowan] had this problem with his whole-house audio system. Playing music required a fiddle with the remote, and the moment was gone. What was needed was an automatic system that simply issued the relevant commands to the stereo without all the fuss.

His solution was to have everything happen when an audio output was detected from his Sonos Connect streaming media player. He tried rectifying its line output to detect music but hit problems, so instead used a SparkFun audio detector module. This in turn speaks to an Arduino, which then talks via a level shifter to the stereo’s RS232 port. [Robert] included all the relevant parts, schematic, and software is links in the video description. It’s a project that should almost be a feature built into a decent stereo, yet the manufacturers prefer the awful interfaces of their remote controls.

Continue reading “Whole House HiFi Tamed Without Fuss”

CES2017: Really, Really Big SLA Printing

Last year at CES, UniZ introduced the Slash, a desktop resin printer. It’s fast, it’s capable, and it’s shipping now, but there was something else in the UniZ booth that had a much bigger wow factor.

The UniZ zSLTV is a gigantic box, a little more than one meter wide, and a little less than one meter tall and deep. Open the lid, and you see a gigantic resin printer turned on its side. The idea here is to fill a gigantic tank with resin, (the build volume is 521 x 293 x 600 mm) and use it as a fairly standard UV LED / LCD resin printer. The only real difference between this machine and any other resin printer is that the part is always submerged in resin.

It’s something we’ve never seen before, and it will be available ‘soon’. The price for this huge machine is in the ballpark of $10,000.