Steering Sound With Phased Array

entiresystem

[Edward] and [Tom] managed to build an actual phased array speaker system capable of steering sound around a room. Powered by an Atmega 644, this impressive final project uses 12 independently controllable speakers that each have a variable delay. By adjusting the delay at precise intervals, the angle of maximum intensity of the output wave can be shifted, there by “steering” the sound.

Phased arrays are usually associated with EM applications, such as radar. But the same principles can be applied to sound waveforms. The math is a little scary, but we’ll walk you through only what you need to know in case you’re ever in need to steer sound with a speaker and a servo phased array sound system.

Continue reading “Steering Sound With Phased Array”

Bare-metal Programming On The Teensy 3

Teensy

The Teensy 3.x series of boards are amazing pieces of work, with a tiny, breadboard-friendly footprint, an improbable number of IO pins, and a powerful processor, all for under $20. [Karl Lunt] loves nearly all the features of the Teensy 3, except for one: the Arduino IDE. Yes, the most terrible, most popular IDE in existence. To fix this problem, [Karl] set up a bare-metal development environment, and lucky us, he’s chosen to share it with us.

[Karl] is using CodeBench Lite for the compiler, linker, assembler, and all that other GCC fun, but the CodeSourcery suite doesn’t have an IDE. Visual Studio 2008 Express is [Karl]’s environment of choice, but just about every other IDE out there will do the same job. Of course a make utility will be needed, and grabbing the docs for the Freescale K20 microcontroller wouldn’t be a bad idea, either.

The end result is [Karl] being able to develop for the Teensy 3.X with the IDE of his choice. He was able to quickly set up a ‘blink a LED’ program with the new toolchain, although uploading the files to the Teensy does require the Teensy Loader app.

Neo Geo Arcade Gets Second Life With A Raspberry Pi

neo-picade

An old Neo Geo Arcade, a Raspberry Pi, and some time were all [Matthew] needed to build this Pi Powered Arcade Emulator Cabinet.

Neo Geo was originally marketed by SNK as a very expensive home video console system. Much like the Nintendo Play Choice 10, SNK also marketed an arcade system, the MVS. The Neo Geo MVS allowed arcade operators to run up to six titles in a single cabinet. The MVS also allowed players to save games on memory cards.

[Matthew’s] cabinet had seen better days. Most of the electronics were gone, the CRT monitor was dead, and the power supply was blown. Aside from a bit of wear, the cabinet frame was solid and the controls were in good shape. He decided it would be a good candidate for an emulator conversion.

We’ve seen some pretty awesome arcade conversions in the past, such as this Halloween rendition of Splatterhouse. For his conversion, [Matthew] stuck to the electronics, leaving most of the old arcade patina intact. The CRT did fire up after some components were replaced. [Matthew] ran into some refresh rate issues with the Raspberry Pi, so he opted to swap it out with a modern LCD monitor. Controls were wired up with the help of an I-PAC board.

[Matthew] had to write a driver to handle the I-PAC, but he says it was a good learning experience. Aside from the LCD screen, the result looks like it could be found in the back of an old bowling alley, or a smokey bar next to Golden Tee. Nice work, [Matthew]!

Air-Tensioned Bandsaw Simplifies Woodworking Life

bandsaw

If you’ve ever had the pleasure of owning a band-saw you’ll know exactly how much fun it is to try to replace the blade, or properly tension it even. [Richard T] got tired of it and decided to upgrade his band saw with a bit of pneumatic power.

To remove the band saw blade or tension it you have to turn an adjustment knob on the top of the band saw — it’s kind of awkward and really annoying. [Richard] has taken the lead screw out and replaced it with a pneumatic cylinder. He’s added a little control panel with a main valve, and pressure regulator. To remove the band saw blade, he bleeds the system with the valve, and to tension it, he turns up the regulator! It’s simple and super effective.

This is especially convenient for tensioning because you can watch the blade during the “Flutter Test” while gently turning up the regulator.

If you look in the right places you could probably build a system like this for less than $50. For a complete explanation stick around to hear it from [Richard] himself!

Continue reading “Air-Tensioned Bandsaw Simplifies Woodworking Life”

Electron Beam Control In A Scanning Electron Microscope

Electron

A few years ago [Ben Krasnow] built a scanning electron microscope from a few parts he had sitting around. He’s done a few overviews of how he built his SEM, but now he’s put up a great video on how to control electrons, focus them into a point, and scan a sample.

The basic idea behind a scanning electron microscope is to shoot electrons down a tube, focus them into a point, and scan a conductive sample and detect the secondary electrons shot off the sample and display them on an oscilloscope. [Ben] is generating electrons with a small tungsten filament at the top of his electron ‘stack’. Being like charged, these electrons naturally fan out, so a good bit of electron optics are required to get a small point.

Focusing is done through a series of pinholes and electrostatic deflectors, much like you’d see in an old oscilloscope CRT. In the video, you can see [Ben] shooting electrons and displaying a Christmas tree graphic  onto a piece of phosphor-coated glass. He has a pretty big scanning area in his SEM, more than enough to look at a few chips, wafers, and whatever other crazy stuff is coming out of [Ben]’s lab.

Video below, along with the three-year-old overview of the entire microscope.

Continue reading “Electron Beam Control In A Scanning Electron Microscope”

Hackaday Links: April 13, 2014

hackaday-links-chain

Check out this Pokemon Yellow cartridge for Super Nintendo. Wait, what? That is a Game Boy game! Well there is a Super Gameboy cartridge that lets you play them on SNES. This mashes the guts of the two into a custom-decorated SNES cart. Now if you’re more interested in the guts of that Super Game Boy cartridge you’ll want to check out this classic hack which dumped the ROM from it. [Thanks Nick]

Here are a couple of interesting things from our friends over at Adafruit. First off, they have a high-res gallery of the Raspberry Pi compute module and carrier boards which we heard about earlier in the week. Also, the latest Collin’s Lab has a great video on soldering. We especially appreciated the discussion of soldering iron tips and their effect on heat transfer.

[Marius] got tired of the static shock from the office coat rack. You know, like the scene straight out of Office Space? But he didn’t disassemble the infrastructure to solve the issue. Instead he connected it directly to ground. Just make sure you stick the wire in the correct hole!

It’s as if Hackaday is on a quest for the most perfect DIY cyclonic separator. Here’s the latest offering which you can cut out from sheet stock by hand. It’s the alternative for those of us without access to a 3D printer.

If you think it’s too difficult to build what we refer to as a Daft Punk table you need to check out what [Dan] pulled off. He proves that your LED matrix coffee table project doesn’t have to take up a ton of time or cost an exorbitant amount of cash.

We should have mentioned this to you before the weekend so you’d have something to watch: you can now download BBS: The Documentary from the Internet Archive. We’ve watched the entire thing and it’s fantastic. If you know what a dial-up modem handshake sounds like, you’re going to be awash in nostalgia. If you don’t know the delight of those sounds you need to watch this and see how things used to be back in the day when connecting your computer to a network definitely wasn’t what the cool kids were doing. [Thanks Larry]

Super Affordable LED Lighting Ready To Go Off Mains Voltage

lights

If you’re looking for a super cheap way to add LED lighting accents to your house, then this hack is for you! Corn-cob style LED light bulbs can be had for a few dollars. The bulbs include driver circuitry, and 8 LED arrays! All you have to do is take it apart.

[Martin Raynsford] stumbled upon this idea when trying to think of a way to light his laser engraving enclosure. It originally came with a regular light bulb, but it didn’t distribute light nicely and was in the way for some of his other planned upgrades.

Not wanting to add another DC power supply to the mix he remembered an old corn-cob LED light bulb he had — as it turns out, they’re pretty easy to take apart! Solder some longer leads on (take note of how they are wired, some are in series, some in parallel) and you’ve just made yourself some easy to use LED accent lighting!

Of course you could just buy those cheap LED rolls from China nowadays for next to nothing for your accent lighting.

[via Hacked Gadgets]