Metalab Bypasses IR Remote With Audio Circuit

November 27, 2015 by Elliot Williams 20 Comments

Infra-red (IR) remotes are great, unless you’re in a hackerspace that’s full of crazy blinking lights and random IR emissions of all kinds. Then, they’re just unreliable. Some smart folks at Metalab in Vienna, Austria cut out the IR middle-man with a couple transistors and some audio software. They call the project HDMI Whisperer, and it’s a cute hack.

Metalab’s AV system has a web-frontend so that nobody ever has to stand up unless they want to. They bought an incredibly cheap 5-to-1 HDMI Switch to switch between displaying multiple video streams. But how to connect the switch to the Raspberry Pi server?

Fortunately, the particular switch has a remote-mounted IR receiver that connects to the main unit through a stereo audio jack. Plugging this sensor into a laptop and running Audacity while pressing the buttons on the remote got them audio files that play the remote’s codes. Simply playing these back out of the Raspberry Pi’s audio out and into the switch’s IR input through a tiny transistor circuit does the trick. Now they have a networked five-way HDMI switch for $10.

Given the low data rates of most IR remotes, we could imagine using the same trick for devices that have built-in IR receivers as well. Simply clip out the IR receiver and solder in a couple wires and then inject your “audio” signal directly.

But IR hacks are loads of fun. We’ve seen a bunch here, from the classic camera shutter-release hack to a more general tutorials on cloning IR signals with Arduinos.

Thanks [overflo] for the tip!

Absurd Clock Uses Twelve ESP8266 Modules

November 26, 2015 by Elliot Williams 15 Comments

Quick quiz: How many ESP8266 modules do you need to make an LED clock? Hint: a clock displays 12 hours.

Nope! Twelve is not the answer. But that didn’t stop Hackaday.io user [tamberg] from building a 12-ESP clock during the Bilbao, Spain Maker Faire. The “advantage” of using so many ESP8266s is that each one can independently control one hour LED and its associated slice of five minute-marker LEDs. Each ESP fetches the time over the Internet, but only lights up when it’s time.

It’s like parallel processing or something. Or maybe it’s redundant and failsafe. Or maybe it’s just an attempt to put the maximum Internet into one Thing. Maybe they had a team of twelve people and wanted to split up the load evenly. (We couldn’t think of a real reason you’d want to do this.)

All snark aside, the project looks great as you can see in this Flickr gallery, and all of the design files are available if you’d like to re-use any parts of this project. We’re thinking that the clock face is pretty cool.

Continue reading “Absurd Clock Uses Twelve ESP8266 Modules” →

Motorcycle Headlight Modulator Is A Bright Idea

November 26, 2015 by Elliot Williams 52 Comments

Motorcyclists are paranoid about being hit by cars, and with reason. You’re a lot safer when you’re encased in a metal shell, with airbags and seatbelts. The mass difference between a car and a motorcycle doesn’t work out well for the biker, either. Unfortunately for bikers, motorcycles are also slimmer and generally less visible than cars.

A few decades ago, motorcycle manufacturers switched over to daytime running headlights to make bikes more visible. In the meantime, however, cars have done the same, leading many bikers to fear that their visibility advantage is losing it’s impact. The solution? Blink the headlights gently during the daytime, and run them normally at night.

[William Dudley] was unsatisfied with commercial versions, so he built a custom headlight modulator for his motorcycle.

And believe it or not, he did it with a 555 timer IC and a light-dependent resistor (plus some transistors and a whole slew of miscellaneous parts). But [William]’s design is a good one, and he walks you through all of the choices he made in building the light-sensing circuit that disables the 555.

Whether you need a motorcycle headlight modulator or are interested to learn how this problem would be solved in the pre-Arduino days, go check out [William]’s post. And while you’re on the nostalgic electronics trip, check out this nixie tube speedometer.

APRS Repeaters Get The Signal Out Of Mammoth Cave

November 25, 2015 by Elliot Williams 55 Comments

APRS Cave-Link uses the amateur radio’s Automatic Packet Reporting System (APRS) inside caves to get their position data (and other messages) out.

Imagine that you’re coordinating a large scale search-and-rescue mission in a cave. You need to know where all your groups are, and whether or not they’ve found anything. But how do they all communicate to the command center?

You’d guess radio, but you’d guess wrong. Radio doesn’t propagate well at all in a maze of twisty passages, all alike; rocks absorb radio waves, especially in the VHF/UHF range that’s best suited for most small radios. In the past, you’d run wire and transmit along it. This article runs through the options in detail. But adding miles of wire to your already heavy caving and climbing gear is a nuisance or worse.

Continue reading “APRS Repeaters Get The Signal Out Of Mammoth Cave” →

“Hello Barbie” Under The Knife

November 24, 2015 by Elliot Williams 43 Comments

In February, Google and Mattel introduced their Hello Barbie Internet-connected toy. This Barbie has an internal microphone, a WiFi connection to Google’s voice recognition services, and a speaker to carry on a “conversation” with the targeted child.

Like the folks at Somerset Recon, we’d say that this is an Internet of Things (IoT) device that’s just begging for a teardown, and we’re totally looking forward to their next installment when they pore through the firmware.

On the hardware front, Barbie looks exactly like what you’d expect on the inside. A Marvell 88MW300 WiFi SoC talks to a 24-bit (!) audio codec chip, and runs code from a 16Mbit flash ROM. There’s some battery management, and what totally looks like a JTAG port. There’s not much else, because all the brains are “in the cloud” as you kids say these days.

From day to day we alternate between the promise of IoT and being anti-IoT curmudgeons, so it should come as no surprise that we’re of two minds about Hello Barbie. First, there’s the creepy-factor of having your child’s every word overheard by a faceless corporation with “evil” in their mission statement (see what we did there?). Next, we’re not sure that it’s OK to record everything your child says to a toy and listen to it later, even if you are the parent. Hackaday’s [Sarah Petkus] summarized this neatly in this article.

But mostly, we’re curious about how well the thing actually works and what it will do with naughty words. And who will take on the task of reviving the Barbie Liberation Organization? Now we totally want to go out and buy one of these things.

Doc Brown’s Security Briefcase Needs Speed

November 24, 2015 by Elliot Williams 16 Comments

If you just wait around long enough, the future becomes the past. And that’s happened to the “Back to the Future” future, as you probably all remember. But BttF-themed projects are still pouring in.

[ossum] sent us the link for his build of Doc Brown’s briefcase that only opens above 88 mph. His writeup is fantastically detailed, and worth a look if you’re interested in working with a GPS unit and microcontrollers, driving seven-segment LEDs with shift registers, or just driving too fast in an old Jetta. And there’s a video demo just below the break if you’re not a believer.

Continue reading “Doc Brown’s Security Briefcase Needs Speed” →

The Ommatid Is An Awesome “Thing”

November 23, 2015 by Elliot Williams 7 Comments

[Jonathan Foote] made a really cool device: the Ommatid spherical display and controller. Part woodworking craft project, part art, and part tremendous hack, the Ommatid is something that we don’t really have a name for. But you can watch it in action, running demo code, in a video below the break.

The sphere design started out with a “20-sided regular polyhedron” with which D&D players should be familiar, and then divided each triangular face into four more triangles. An 80-sided die? Almost. One triangle’s worth was sacrificed for the part that mounts to the base.

Each facet contains an RGB LED and an IR sensor so that it can tell when a hand is nearby. All of this input and output is run through a Raspberry Pi, so both the sensing and display interactions are easily modified. [Jonathan] runs us through the electronics, programming, and interactivity in a separate Instructable. We really like [Jonathan]’s idea of turning this device into an OSC controller / display.

Continue reading “The Ommatid Is An Awesome “Thing”” →