[i-TRIXX] This is the AND, my friend...

  E-weekly's i-TRIXX news items cover all nooks and crannies of electronics. This week we will start off in a simple way by taking a look at Logicly, a simulator for logic gates. You can find it at http://joshblog.net/projects/logic-gate-simulator/Logicly.html
The program allows you to become acquainted with logic gates such as AND, NAND, OR and NOR, in a user-friendly way. It also lets you fool around with the basics of Boolean algebra. The gates can be dragged in to a virtual design area; there's a switch, a clock generator for the input signals and a lamp to signal the output status. The connections between components can be made by dragging one terminal on to another. If you need more help, check out the Help file. The program was designed by Josh Tynjala.

Now for something a little more complex.
Do you remember the question about the resistor value of the Electronic Ball? About finding a method to calculate it? A couple of fine minded people have risen to the challenge and.... some of you might not like the outcome. Because the calculations once again confirm that fools ask questions that wise men cannot answer.

Two Elektor readers, Carlo Cianferotti and Bernhard Foltz both sent an elaborate document with their method of getting the correct value. Both solutions are based on symmetry and matrix calculations. Carlo has provided an English version, Bernhard a German one. You can browse them at your own leisure at theelectronicball.blogspot.com. I would like to use this blog for your answers and replies. I hope to address the recently launched issue of ‘PHI’ in electronics there soon.