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Archive 2010 Tech Talk By Jim Purvis WA7HRG In lasts months column I presented some explanation of Ohms Law and how it related to Voltages, Current and Power in a circuit. Along with that was a simple resister network and a challenge to calculate the voltage, current, and power for each component. And as promised, here are the answers. Answers to the Ohms Law Challenge 1 Total Equivalent Resistance = R1+ 1 + 1 R2 R3+R4 =1K + 1 .0002+.0005 =1K+1428.5 =2,428.5 ohms Total...

Archive 2010 Tech Talk By Jim Purvis WA7HRG We were sitting around the restaurant one night drawing pictures on a napkin and reviewing ohms law. Made me stop and think bit. I thought it might be fun for the old timers to dig back in the memory banks and would be educational for those new hams that have heard about ohms law but never worked with it, to dust off the calculator, review the formulas, and sharpen up the #2 pencil. The Law and where it came from Ohm's law states that...

Archive AUG 2010 Tech Talk By Jim Purvis WA7HRG What the heck is a Balun?? A "BALUN" is a bi-directional adaptor between a BALanced device and an UNbalanced device. Twin-lead feedlines and dipoles are "balanced" (two signal conductors, with equal-but-opposite current: symmetrical). Coax cables and the typical antenna port of a transceiver or antenna tuner, are "unbalanced" (one signal conductor that is referenced to ground; a.k.a. "single-ended"). Baluns other than those with a 1:1...