The other day, I got a phone call from a former student. He was a bit perturbed because he’d started studying for the Extra Class exam, and right off the bat, he found himself in some deep water.

The first topic that I cover is resonance. I jump right in and define resonant frequency as the frequency at which inductive reactance of a circuit equals the capacitive reactance of a circuit. That is when 2πfL=1/(2πfC), and if you do the math, the resonant frequency, fr = 1/(2π√(LC).

Now, I’m going to take some of the blame for my friend’s predicament. The reason for this is that I really didn’t review the idea of reactance. I just assumed that they’d recall this from the General Class material. When I explained this over the phone, he got it, but I can see where my study guide could be a little confusing.

This Morserino32 kit arrived yesterday, and I’m hoping to build it tonight. If you’re not familiar with this little beauty

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