Over at The Signal Path Blog  Shahriar Shahramian has a look at a Fluke 196B Handheld ScopeMeter that he purchased from an eBay seller. The meter was purchased for a few hundred dollars and was listed with a fault that is doesn’t power up. It didn’t come with probes, a back cover or the battery. Shahriar was ready for a full tear down and hopefully a repair but as it turns out the meter worked just fine! Not sure how cheap these surplus dealers get some of these test gear lots but I am guessing it is pennies on the dollar of operational value and they just sell them as non working because they can’t be bothered (or don’t have the capability) of performing any functional testing. Good thing is we get to see a full tear down of the meter along the way. At 32:40 you can see an interesting method of chip cooling and shielding that fluke has used in this unit. This thing is built very well as you would imagine for the price point and the fact that it is a Fluke.

Even the most modern cars (except possibly ones made by Tesla) don’t provide much computing power that the user can harness. EEVBlog user Ptodorov wanted to have the power of a mini computer in his car. Only thing is a computer doesn’t interface with real world things like door switches and turn signals very well. To interface with the car hardware an Arduino and a relay module was used. Things haven’t been all smooth sailing though since the system has gone haywire while driving and the system does draw a bit too much current when off but it is a great start and inspiration.

“For the last 5-6 months everything ran fairly smoothly with a few glitches and bugs. But a few weeks ago all hell broke loose
while I was driving. Suddenly left and right blinkers started flashing, the headlights started blinking and doors kept locking and unlocking.
This kept happening for a good 30 seconds. Fortunately there were no other cars around me. Also when the winter came the arduino started draining the battery more noticeably, after leaving the car for several days it didn’t start with the first turn of the key even trough I’m putting the MCU in sleep and waking it on an interrupt from the remote control. The battery drain was 250mA and after I disconnected everything I’ve done from the car it drop down to 120mA.”

So if making a robot that can be remotely controlled wasn’t a tough enough challenge the guys over at Ufactory decided to make one that can roll around on a ball. Great looking design and it sounds like they are going to do a Kickstarter for it and release it as open source hardware to the community. I can’t wait to see a larger version that can be ridden around!

Via: Make

“The hardware may include: Gyro sensor, Accelerometer, Geomagnetic sensor, Wireless module, WIFI module, Camera, Kinect, STM32 MCU, Atmega16 MCU, Brushed DC motor (with gear box), encoder, DC motor driver, Controller power supply and motor power supply.”

 Rohit Gupta needed a way to speed up PCB etching. Heating the etchant and agitating it are both well known ways of speeding up the process. If you are on a DIY budget this normally means you will be stuck sloshing the etchant back and forth for 10 minutes or so. Rohit developed the Open Agitator which uses a CD-ROM Drive Drawer to shake a tray back and forth. A MSP430 microcontroller and an L293D H bridge motor controller are used to power the CD-ROM drive motor, recycled mouse buttons are used as end stop sensors. This is a great project since is simply adds a simple circuit to a platform that most of us have laying around in our junk bins. 

Via: Dangerous Prototypes

The raspberrywebserver.com is running on this Raspberry Pi Cluster Web Server. Visit the site to see all of the details so you can build your own. Steve figures that a 20 Raspberry Pi cluster would be equivalent to a PC server so it isn’t as powerful as a full blown server but it feels very fast and responsive when I tried it!

Via: HG Comments

“Clusters can be used as web servers. Many web sites get too much traffic to run on a single server, so several servers have to be used. Requests from web browsers are received by a node called a load balancer, which forwards requests to worker servers. The load balancer then forwards responses from servers back to the clients.

FozzTexx shows how he built a system that allows a Raspberry Pi to act as a Commodore 64 Disk Drive. His C-64 is tricked out with an Ethernet card so he shows us how he can pull a directory listing from the Raspberry Pi drive and loads an internet browser. It works but isn’t really usable for anything modern. The drive access is very slow due to the speed limitation of the C-64 bus. The software is available for free on Github.

Josh Kiepert built this Raspberry Pi Cluster while at the Electrical and Computer Engineering department at Boise State. He didn’t want to rely on the stability of the Beowulf cluster at the university while working on his doctoral research so he decided to build his own using 33 Raspberry Pi computers. He has stacked them wired them with a custom power interface so that he can keep the power lines to a minimum, although each system still has an Ethernet cable running out the back of the enclosure.

“I had need of a cluster to run a distributed simulation I’ve been developing. The RPiCluster is the result. Each RPi is overclocked to 1GHz and is running Arch Linux. This demo shows the RPiCluster running a parallel program I developed using MPI to control all of the RGB LEDs installed on each of the nodes.”