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Hackaday Links: September 4, 2016

September 4, 2016 by 28 Comments

Nozzle socks! Just keep saying, ‘nozzle socks’ until the semantic satiation undoes any semblance of sanity. E3D, makers of the world’s finest 3D printer hotends have released silicone nozzle covers that prevent caramelized plastic gunking up your hot end. Nozzle socks.

Let’s talk guitar pedals. If you’ve ever built your own guitar pedal, you probably stuffed it inside a Hammond enclosure. There’s more to guitar pedal enclosures than custom-painted electronic boxes, and arguably the best enclosures are the ‘Boss’ style – a metal cover over the switch that can be removed to access the battery independently of the circuit. Now you can buy this type of enclosure. [Rixen] is producing blank die-cast aluminum pedals that look so much better than the standard Hammond enclosure.

The Antonov AN-225 is the largest and heaviest airplane in the world. Only one was built. For the last thirty years, a second airframe, about 70% complete, has sat in a field or hangar in the Ukraine, waiting for someone to put it into service. After numerous false starts over the past decade or so, the second AN-225 is finally being built.

The Hackaday Retro edition is our version of Hackaday optimized for embedded devices. When someone gets some old hardware on that vast World Wide Web and manages to pull up the retro edition, we like to celebrate. [Michael] recently got his old Amiga 1200 online and managed to find the software and hardware to get this machine on the net. Inside the A1200 is a 4GB CompactFlash, an ACA 1232 accelerator card with 128MB of RAM and a 33MHz 030. The network is handled by a Linksys EC2T card, and the software is KS3.0, WB3.1, MiamiDX IP stack IBrowse 2.4, and a bunch of 3rd party libs he can’t remember. Here’s a pic.

On a related note, I haven’t touched the Hackaday Retro Edition in years. Right now, it’s just a script running every five minutes that assembles five random posts from the first 15,000 Hackaday posts since the beginning of time. The retro edition does what I want it to do, but I’m wondering if it can be better. If you have an idea of how to improve the Retro Edition, leave a note in the comments.

Carbon Nanotube Transistors Are On The Passing Lane

September 4, 2016 by 22 Comments

There are many obstacles in the way to turning carbon nanotubes into something useful. Materials engineers at the University of Wisconsin-Madison have now brought carbon nanotubes (CNTs) one step closer to becoming practically applicable for semiconductor electronics. In particular, the team managed to assemble arrays of carbon nanotube transistors that outperform their silicon-based predecessors.

Continue reading “Carbon Nanotube Transistors Are On The Passing Lane” →

Music Player For The Ability-Impaired

September 4, 2016 by 19 Comments

Most of the hacks we come across here at Hackaday don’t require much more than being “cool” to get our attention. But, every so often we find something that goes a step beyond that and does something truly good for the world. This is one such project, and its goal couldn’t be anymore altruistic: to allow the elderly to enjoy music, even when their declining vision and motor skills make traditional devices difficult to use.

It’s hard to overstate how important music is to people; there are few forms of art more emotionally effective. So, it was a major loss when an elderly relative of [DusteD] was no longer able to operate their CD player. Luckily, [DusteD] was there with an ingenious solution that uses RFID cards to play music from an always-on Raspberry Pi.

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Convert Any USB Keyboard To Bluetooth

September 4, 2016 by 40 Comments

[DastardlyLabs] saw a video about converting a PS/2 keyboard to Bluetooth and realized he didn’t have any PS/2 keyboards anymore. So he pulled the same trick with a USB keyboard. Along the way, he made three videos explaining how it all works.

The project uses a stock DuinoFun USB mini host shield with a modification to allow it to work on 5V. An Arduino mini pro provides the brains. A FT-232 USB to serial board is used to program the Arduino. A standard Bluetooth module has to have HID firmware installed. [Dastardly] makes a homemade daughterboard–er, shield–to connect it to the Arduino.

The result is a nice little sandwich with a USB plug, a Bluetooth antenna, and some pins for reprogramming if necessary. Resist the urge to solder the Bluetooth board in–since it talks on the same port as the Arduino uses for programming, you’ll have to remove it before uploading new code.

If you need help reprogramming the HC-05 Bluetooth module, we’ve covered that before. This project drew inspiration from [Evan’s] similar project for PS/2 keyboards.

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Raspberry Pi Chiptune Player Rocks A Sound Chip From The 80’s

September 4, 2016 by 13 Comments

Sometimes it’s worth doing something in an inefficient way. For example, it might be worth it in order to learn something new, or just to use a particular part. [Deater] did just that with the Raspberry Pi AY-3-8910 Chiptune Player (with LED visualizers!)

The venerable General Instrument AY-3-8910 series sound chips were common in older hardware like home computers and game consoles as well as sound cards for the Apple II family. They were capable of generating three channels of square waves with various effects. Developers eventually squeezed every little bit of performance out with clever hacks. The Raspberry Pi has more than enough power to do all this in software, but as [Deater] puts it, it’s far more interesting to use an actual AY-3-8910 from the 80’s. Some LED bar graphs and matrices round out the whole system.

All the code for the Raspberry Pi AY-3-8910 chiptune player can be found on [deater]’s github repository for the project. A video of the player banging out some sounds is embedded after the break.

Continue reading “Raspberry Pi Chiptune Player Rocks A Sound Chip From The 80’s” →

Russian Hacker Multiplies Value Of Boost Converter

September 4, 2016 by 23 Comments

We have a love/hate relationship with LiIon batteries. They pack all this power in such a small and light package. But for running 3.3 V devices, they’re cumbersome. They need to be stepped down a little bit when they’re fully charged at 4.2 V, but then they need to be stepped up at the end of their charge around 3.0 V.

A simple boost or buck converter can’t do both jobs, although you’d be tempted because they can be purchased for peanuts online. So [Kirich] hacked cheap boost converters into the more capable SEPIC topology, which sell for nearly 10x as much. (Google translated version here.) The bottom line? With a little desoldering, a cut trace here and an extra inductor there, and [Kirich] had a very capable circuit that would maintain a constant 3.3 V output when the input swung between 1 V and 5 V.

95aa17If SEPIC power converters are foreign to you, have a read through Maxim’s white paper on the subject. Basically, it’s a boost converter with a capacitor in the middle that lets the output voltage drop below the input voltage. An extra inductor keeps the output side of this capacitor at ground potential (on average).

If you want more detail, [Kirich] doesn’t disappoint. He tested his modifications in multiple configurations on two different models of boost converter. As you’d expect with power circuitry, layout and trace length matters, and [Kirich] took good notes. This is a great read for the frugal hacker, or anyone who’s interested in boost/buck converters.

Speaking of boost/buck circuits, we’ve got some more links for you. This video from Sparkfun’s [Pete Dokter] is worth fifteen minutes, and if you want to get your hands really dirty in the construction of such circuits, this ATtiny-based boost converter circuit is fun to play with.

Thanks [kirillre4] for the great tip!

Bathroom Status Reporting Hack Eliminates Lines, Frustration

September 4, 2016 by 20 Comments

In a lot of ways, portable toilets are superior to standard indoor-plumbing-style toilets. This is mostly due to the fact that they have a status indicator on the door. It’s a shame that no indoor bathrooms have figured this out yet, especially in office buildings where your awkward coworkers bang on every door rather than just check for feet in the huge gap that for some reason exists between the floor and the stall door. Anyway, [Chris] and [Daniel] came up with a solution for this issue, which also eliminates wait time for bathrooms in their office.

Their system is an automated bathroom status indicator that reports information about the bathroom’s use over WiFi. Since the bathrooms at their facility are spread out, it was helpful to be able to look up which bathroom would be free at any given moment. Several Raspberry Pis form the nerves of the project. Custom sensors were attached to a variety of different door locks to detect status. Each Pi reports back over WiFi. This accomplishes their goal of being subtle and simple. They also point out that they had to write very little code for this project since there are so many Unix and embedded hardware tools available to them. Checking the status of the bathroom can be as simple as running netcat.

If you’re looking to roll out your own bathroom status monitor solution, [Chris] and [Daniel] have made their code available on GitHub. There are a number of other ways to automate your bathroom, too, like switching the exhaust fan on when it gets too smelly or humid, or even creating a device that dispenses your toilet paper for you.