Re: Copper Tape Antenna Q&A's
Jim Rodrian
Barry,
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DC resistance has nothing to do with AC impedance. Ohms Law, V = I x R, is very simple and accurate if you are connecting a 12V battery (DC) to a 12V landing light. Fifth grade math works very well to calculate what happens when the battery is connected to the light bulb. RF (radio frequency) signals are AC (alternating current) signals. When the frequency of oscillation is in the range of 122.8 MHz, capacitive and inductive impedances determine what is a "short" or "open" and how energy, no matter how small, flows through intended conductors. In principle, V = I x R still works but the formulas are based on college calculus and traveling wave theory (more calculus). Sometimes the calculus type equations can be simplified to algebra type equations, but only if valid assumptions are made. The algebra type equations are usually what you see in the "how to" literature. For conclusions regarding antennas, see John Rippengal's prior posts. He has the experience and knowledge to know what works and what doesn't work. Jim Rodrian, BSEE Defiant - in the finishing process
The Experiment :-
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