Wireless Arduino message board

arduino_message_board

[uhclem] was looking for a novel yet easy way to remind his kids to do their chores, and instead of using a series of post-it notes, he constructed a nice wireless Arduino-powered message board.  The message board is powered by an Arduino Pro, and communicates with his computer via a pair of series 1 Xbee radios which relay a … Read the rest

Grinding down your computer to just 8.5 watts

What can you do to make sure your system is running as efficiently as possible? Take a page out of [Mux's] book, who went to great lengths to measure and adjust his system for ultimate efficiency (translated). What he ended up with is 8.5 Watts of consumption at idle and about 50 Watts under load. Luckily he posted … Read the rest

555 Timer circuit simulation software

ltspiceiv_demo

[FightCube] wrote in recommending a very helpful piece of circuit simulation software for those of you still constructing entries for the 555 design contest.   LTSpiceIV, available from Linear Technology, allows you to construct moderately complex 555 driven circuits including common components such as capacitors, resistors, diodes, FETs, and more.  Once you have constructed your circuit, you can view the … Read the rest

Update: Open source pick-and-place

[Tim's] been busy moving his pick-and-place build toward completion. We looked in on the first version of the vacuum head back in October. Since then he’s ditched the camera enclosure which allows for more light and better mounting. The tip has been replaced by one from a pair of vacuum tweezers, and the whole thing is now mounted … Read the rest

Mixed I/O testing module

Needing to test the display interface for a multitude of different sensors [Fileark] built himself this analog and digital input/output simulator. Along the bottom is a double row of trimpots that adjust analog voltages. Each voltage is measured by the Arduino inside and its value is displayed on the graphic LCD screen to confirm that the hardware you’re testing … Read the rest

Theremin midi board is like using autotune

[Steve Hobley] built a Theremin interface board that tracks pitch and volume. Using this setup he’s able to pass data over a midi interface which effectively converts the instrument into a non-contact midi controller. As we joked in the headline, this does allow for the use of autotune, by snapping notes that are sharp or flat to the center … Read the rest

FareBot – Android NFC Proof of Concept

farebot_logo

Upon learning that the Nexus S smartphone was equipped with a Near Field Communications NFC) radio, [Eric Butler] decided he would put the newly released Gingerbread SDK to good use.  Focusing initially on ORCA fare cards used by several Washington state transit systems, he built an open-source application he calls FareBot, which can read data from any MIFARE DESFire … Read the rest