At last night’s monthly meeting of the Chelsea Amateur Radio Club (7-12-2022, WD8IEL), it was decided that the Chelsea Amateur Radio Club would sponsor weekly electromagnetic training sessions by Zoom. This will be open on a global scale to the amateur public. Initially, Wes Cardone (N8QM) will be the sole presenter, but volunteer presenters are warmly encouraged to sign up (please help!). Wes can’t do it all by himself forever.
WHO, WHAT, WHERE, WHEN, AND WHY:
When: Tuesday evenings (in perpetuity) from 6pm to 7pm.
Topic: The Simplified Smith Chart and More
Purpose: An electromagnetic path for Tech amateurs to upgrade
Prerequisites: You must have an amateur Tech License
Zoom Login: Please visit the CARC website at wd8iel.com
When Begins: August 2, 2022
Fee: None
DISCUSSION:
While the official name includes “Smith Chart,” it will be all of the things that go into understanding the Smith Chart as well as the Smith Chart itself. The next question, of course, is: What are those things? The simple answer is: simplified electromagnetics. The purpose of the Smith Chart is to reduce to an intuitive nature much of electromagnetics. But in order to use the Smith Chart, you first have to know what it is that you are solving or working with for a solution. But let us emphasize the word “simplified.” The target student has virtually no professional electronics knowledge. We will move slowly but with determination. The class syllabus will be largely defined by who attends and likely be a moving target. Regular attendance is neither expected nor requested.
The name Smith Chart in the class title is a convenience. We sought a title that was simple but yet suggests amateur radio FCC pool question subject matter that tends to intimidate most non-technical amateurs.
Those without amateur licenses at all are still welcome to attend. I just don’t want to entertain questions from them unless I adjudicate that the questions are what I expect from a Technician Class licensee.
Here’s what we are looking for in volunteer presenters: We ask that you hate cookbooks and tell other amateurs that they also should hate cookbooks.
A cookbook approach to learning has you memorizing many equations and rules and procedures. That’s too hard. We would like to take a simpler approach. Let’s understand the physics involved from 20,000 feet. Let’s capitalize on what the student already knows. For example, he or she already knows that if you touch a broken lamp cord wire with both hands you will be looking for a box of BandAids. Therefore, he or she already knows what an open circuit is. Knowing what an open circuit is, we can then talk about the antenna which is an open circuit, and now understand exactly why the voltage and impedance are both maximums at the ends. We then have an excellent position for launching into characteristic impedance and its nature.
Everybody else just tells you to remember that the voltage is a maximum at the ends which is a cookbook approach that you will forget. I hate cookbooks and you should hate cookbooks, too. They make electromagnetics too hard.