Windell H. Oskay from EMSL created a detailed discussion on using Zener Diodes. He has designed a circuit flow using Zener diodes to control the reverse breakdown while designing up a circuit which is impossible to do if he would had used a regular diode.

“Zener diodes are a special type of semiconductor diode– devices that allow current to flow in one direction only –that also allow current to flow in the opposite direction, but only when exposed to enough voltage. And while that sounds a bit esoteric, they’re actually among the handiest components ever to cross an engineer’s bench, providing great solutions to a number of common needs in circuit design. “

If you have a junk box full of all sorts of motors from printers, scanners and other discarded tech you need to know what you have so you can use it in your next project. Thanks to Steaky for sending in this info that was written to help you determine what type of stepper motor you have and how to use it.

“Not only do stepper motors come in a variety of shapes and sizes, they also have different coil configurations. This can help identify how to drive the stepper motor, and what sort of controller you are likely to need to drive the motor. Stepper motors typically have 4,5,6 or 8 wires, and these can be used to identify the type of motor. There are two types of stepper; Unipolar and Bipolar. This refers to how each coil is driven. A unipolar stepper only requires each coil to be driven in one direction, whereas a bipolar requires driving in both directions.”

There are lots of surface mount parts out there that aren’t available in DIP format. Normal DIP format chips and various other parts have pins that are configured with a 0.1 inch spacing. Breadboards make prototyping a circuit fast and easy since there is no soldering involved, it is literally plug and play. If the connections need to be changed all you do is pull the wiring out and position it where you would like it.

But what happens when your part is not in a 0.1 inch format? There are lots of pin converters from companies like Spark Fun that allow you to solder surface mount parts to them and they have the popular 0.1 inch pins so that you can now simply plug it into your breadboard.

But what happens when you have a very strange high pitch connector that you would like to connect to your bread board? Per Jensen from Zapro shows us his solution here, he had a bunch of LCDs with a fine pitch ribbon cable that he wanted to use with his projects. Some very fine wire, a soldering iron with a pointy tip and nerves of steel is all that is needed to bridge between the flex cable and the breadboard pluggable pins. Since this fine wire could break with just the slightest movement, the most important thing to do is isolate the new fragile connections. Per uses some hot glue to stabilize the entire convertor so that it can be handled without the worry of the wires breaking, only issue here is you better be sure that you have it wired up exactly as you want it because unlike solder hot glue is hard to reverse. 

Remember the game Breakout? These days with game controls like the Kinect who wants to use the old style joysticks anymore?  ECE 5760 students Meng-Ling (Maxwell) Liu, Thu-Thao Nguyen and Yang Yang designed a game that they call HAND BREAKING BRICKS. They are using an FPGA to display the game on the monitor while it is also monitoring a Terasic CCD module which allows the game to “see” the location of the players hand. The players hand location directly reflects to the location of the ball bouncing bar.

Read more about HAND BREAKING BRICKS here.

“In order control the game using hand motions, we need a device to track hand movement. We chose the Terasic CCD kit, which consists of a 1.3 megapixel CMOS image sensor and an IDE cable to connect to the GPIO port of the DE2 board. We followed the provided code to learn how to use the camera in the kit.
The current image is captured by the camera and sent to the DE2 board, then each video frame is stored in the SDRAM. We detected the hand position in the recorded frame using the skin color detection scheme in the top module.”

If you have taken some CS courses you have no doubt seen Conway’s Game of Life, if you are a kit builder you have probably seen some nice Conway’s Game of Life kits also. Where the basic kit version has 16 elements Cornell University student Cooper Bills wanted to design a system that had 307,200 elements. What this boils down to is an incredible looking visual effect that requires a massive amount of calculations. Luckily this project was undertaken in the Cornell University Advanced Microcontrollers course (ECE5760) where students had the choice of Altera/Terasic DE2 or DE2-115  FPGA educational boards to work with.

Read more about this FPGA Conway’s Game of Life project.

“The main goal of this project was to implement Conway’s game of life on a grid of 640×480 cells, running at 60Hz. Updating that resolution at that rate requires over 18 million updates per second! This leaves just a few clock cycles per cell for updating. Given that each cell requires 9 values to calculate it’s next value, even with extreme pipelining serial updating would not be possible (without over-clocking).”

Collin Cunningham from Make gives a good introduction to what an electronic schematic is and how to properly read them. You can read more about schematics here, to see lots of practical examples this is a good start.

“Schematics are the functional diagram of electronic circuits. With so many designs available on the web, understanding how to read schematics can unlock a world of possibilities for the electronics maker”

In the latest Solid State Technology magazine there is a great article about the Nobel Prize in chemistry being awarded being awarded to Dan Shechtman. Subscribing to the Solid State Technology magazine is free as long as you are in USA, if you are outside the USA you can subscribe to the digital version. Hacked Gadgets does receive a small payment for each subscription to any of our Free Magazine Subscriptions so we appreciate the support from all who subscribe to the free magazines that we offer.

“The Royal Swedish Academy of Sciences awarded this year’s Nobel Prize in Chemistry to Dan Shechtman, Technion – Israel Institute of Technology, Haifa, Israel, for the discovery of quasicrystals.

Shechtman discovered the solid-matter arrangement in April 1982, using an electron microscope. Until his research, all solid-matter atoms were believed to be packed inside crystals in symmetrical patterns that were repeated periodically. Scientists considered this repetition required in order to obtain a crystal.

Shechtman showed that the atoms in his crystal were packed in a pattern that followed mathematical rules but could not be repeated. The controversial findings led to Shechtman being asked to leave his research group. However, his battle eventually forced scientists to reconsider their conception of the very nature of matter.

Shechtman’s quasicrystals are now described by “the golden ratio;” the ratio of various distances between quasicrystal atoms is related to the golden mean.”

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