Is Your Camera Lying?

January 17, 2011 by James Munns 25 Comments

It is easy to rely on the ratings marked on different tools, whether it is a power supply, scale, or speedometer. However calibration is essential for any part that is relied upon either professionally or for a hobby. [Jeremy] wanted to see if his Lomography camera shutter really was only open for 1/100ths of a second when set to that. In order to test his rig, he set up an LED on one side of the shutter, and a high speed phototransistor to gauge the time spent open, using an oscilloscope to measure the time the reference point was pulled low. In his case, when the camera was set to 1/100, the shutter was actually open for closer to 1/150th of a second (the mean was 1/148ths of a second, with a standard deviation of 417 uSecs). This difference can make a large difference in picture brightness.

Be sure to check his blog for more pictures of the setup, as well as some useful part references and circuit diagrams.

Audio Crossover Back In Service

January 17, 2011 by James Munns 24 Comments

Audio Crossovers are an essential tool for any high end speaker system. Because most individual loudspeakers are unable to cover the entire spectrum of audible sound as well as multiple drivers are, it is necessary to split the input signal into low and high frequency parts. When a friend of [Anthony]’s was about to send off a classic Klipsch AA Crossover to be repaired professionally, [Anthony] insisted it was possible to save some money and do it himself.

The oil can capacitors of the Crossover had gone bad, so a new set of metalized polypropylene capacitors were ordered to pick up the task. After carefully removing the old caps, [Anthony] assembled the new set on a breadboard, and mounted the board to the old Crossover base (along with some tasteful McDonalds straw spacers). The entire process is detailed on his blog, and we are sure his friend saved a good deal by this home repair method. Capacitor issues are a common problem in repairing electronics new and old alike, and always a great place to start looking when devices start acting funny.

Macintosh Plus DJ Helmet With An IPad

January 14, 2011 by James Munns 39 Comments

Elaborate helmets are not a new concept, with many famous artists such as Daft Punk and Deadmau5 using them for stage shows. For a sculpture class, [Terrence] fashioned his own out of the body of a Macintosh Plus and an iPad conveniently sourced from eBay. After gutting the insides, the Mac Plus was fitted with parts from a helmet both for comfort as well as for keeping the whole setup head mounted. For additional eye candy, an LED visualizer was affixed below the iPad display. The rig is remotely controlled by a bluetooth keyboard, just for good measure. We think this setup easily stands up to other Daft Punk-esque style head mounts.

Be sure not to miss the video of the helmet featuring DJ Chameleon (a friend of [Terrence]) in action, as well as a number of other photos.

[Edit: Thanks to everyone who caught the Mac Plus/Pro error!]

Open Source Your Rave With OpenLase

January 14, 2011 by James Munns 26 Comments

Without a doubt, Laser Projectors are a great way to project large, bright images on any surface you can imagine. With a high enough quality projector and software package, excellent images and visualizations can be displayed in real time. [marcan], of the openkinect project, decided that there were not any open source laser projection packages out there that suited his wants or needs, so logically he decided to write his own. Because home-made laser projectors often use the audio out port of a PC, building the framework on top of the JACK unix sound software to control the hardware made perfect sense. OpenLase includes plugins for audio visualizations, 2D and 3D gaming, as well as converting video streams into laser format in real time.

Be sure to check out the Chaos Communication Congress presentation [marcan] gave after the break, as well as all the extra demo videos on his website.

Continue reading “Open Source Your Rave With OpenLase” →

Speed Up Web Browsing In Linux

January 11, 2011 by James Munns 46 Comments

In modern computer systems, the biggest bottleneck of information tends to be in communicating with the hard disks. High seek times and relatively slow transmission rates when compared to RAM speeds can add up quickly. This was a necessary evil back when RAM space and costs were at a premium, but now it is not uncommon to see 4GB of RAM on laptops, and even 12GB on desktops. For users whose primary computer use is browsing the internet (either for work, writing articles, or lolcats) and have some extra RAM, moving the browser cache to the RAM from the hard disk is a definite option for increasing speed.

In Linux systems (specifically Fedora and Ubuntu systems), this can be achieved for Chrome and Firefox by creating a larger ramdisk, mounting the ramdisk after boot, and then setting the browser of choice to use that ramdisk as a cache. The necessary commands to do this are readily available (internet archive) on the internet, which makes life easy. Using ramdisks for performance boosts are not exclusive to browsers, and can be used for other software such as Nagios for example.

We have previously covered a tool called Espérance DV for moving cache to RAM in Mac OSX, and for any Windows users feeling left out, there are ways of making Firefox bend to your will. Obviously you will see an increase in RAM use (duh), but this shouldn’t be a problem unless you are running out of free RAM on your system. Remember, free RAM is wasted RAM.

Custom Made Industrial Hookah

December 29, 2010 by James Munns 44 Comments

Since their invention in the 1500s, Hookahs have always been a way for craftsmen to show off skills by creating ornate, elaborate, and functional pieces of art. This still holds true today, as easily seen above. Found on the Hookah subreddit, this pipe was pieced together by recycling an old vodka bottle, as well decorating and re-purposing a number of plumbing items. Some finishing touches such as LEDs and gears to the base, as well as a set of turn-valves to the hose plugs give this hookah a very distinctive look.

As always, we at Hackaday do not recommend or promote smoking, no matter what goes into the bowl of the hookah. However, whether you smoke or not, the final product is worth appreciating. Be sure to check out the higher resolution pictures after the break.

Continue reading “Custom Made Industrial Hookah” →

A Tricycle Built For Plowing

December 29, 2010 by James Munns 27 Comments

What do you get when you combine two bikes, a couple levers, and a home made wooden shovel? Why, a light duty tricycle plow, of course! [Craig] of Firefly Workshop cobbled together this contraption to assist him in shoveling his 90′ driveway when a few inches fall. More convenient than a normal shovel, and much more environmentally friendly than his 8 Horsepower snow blower, this trike looks like it could actually make shoveling the snow fun. Not really much more here than meets the eye, we just wish we had a video to share of this sweet ride in action.