This was a particularly enjoyable issue to put together, largely due to the cover story that involves the EMC Society’s Experiments Manual. This document was first developed by the IEEE EMC Society Education Committee in 1987 and revised in July 1992. The editors were Henry Ott and Clayton Paul. This document inspired a student at the University of Michigan-Dearborn, Chris Semanson, to spend 30 hours a week for 14 weeks this year to review the experiments! His goal: Use the Experiments Manual as a guide to design and build experiments that closely followed Henry Ott’s new book, Electromagnetic Compatibility Engineering (reviewed in the Spring 2010 issue of this Newsletter), the proposed draft of which was used as a textbook in his EMC course.
As a bit of background, Chris Semanson is a student of Mark Steffka, an adjunct professor at the University of Michigan-Dearborn. Mark has long been active in the EMC Society. In 1999, his University received a $10,000 grant from the EMC Society to develop an EMC course. Mark taught the EMC course and contributed an article for the Winter 2003 issue of the EMC Newsletter to review how the university developed the EMC course and to summarize what the students had learned in the four years since the grant was issued.
When I casually asked Mark recently what was new at his university, I learned the latest about his EMC course, his “testing” of Henry Ott’s new book in his course, about his enthusiastic student Chris Semanson, and about their work involving the EMC Society’s Experiments Manual.
I was a bit intrigued to learn more about the Experiments Manual; after all, what was in the document that inspired a student to volunteer over 400 hours to review it? I obtained a copy and proceeded to delve into the text.
While the document contains a wealth of information, due to space constraints, I’ll touch on some of the more interesting facets. I have taken the liberty of reprinting below the introduction to the EMC Society Experiments Manual, “Intent of the Material”. I thought you would find this introduction and mention of the FCC’s 1979 launch of Part 15, Subpart J as part of its Rules and Regulations interesting. Just 30 years ago, people realized the importance of EMC in digital devices and the Government took steps to ensure the compatibility of digital devices. Dr. Paul’s comment that companies “cannot afford the cost and schedule delay consequences resulting from their digital designers being unaware of EMC design principles” is still true today. In fact, while digital designers may now have a greater awareness of EMC, the challenge in today’s world seems to be educating product managers on the importance of EMC – that is, addressing it earlier in the design phase than later!
INTENT OF THE MATERIAL
“The intent of this material is to aid in the establishment of a course in Electromagnetic Compatibility (EMC) at a university in an Electrical Engineering program. Several institutions in the US and throughout the world offer such a course. However, there is a growing need for more institutions to incorporate such a course in their undergraduate Electrical Engineering curricula. For a further discussion of the rationale for such a course, see C.R. Paul, “Establishment of a University Course in Electromagnetic Compatibility (EMC)”, IEEE Transactions on Education, Vol. 33, No. 1, pp. 111-118, February 1990.”
“In 1979, the Federal Communications Commission (FCC) in the United States imposed a rule in its Rules and Regulations, Part 15, Subpart J which makes it illegal to market a digital device that has a clock frequency greater than 9 kHz unless the radiated and conducted (out the ac power cord) emissions of the device have been measured and found to not exceed the limits set by the FCC. The FCC limits on the conducted emissions extend from 450 kHz to 30 MHz, and the limits on the radiated emissions extend from 30 MHz to 40 GHz. Digital products that are to marketed in other parts of the world are subject to similar and no less stringent requirements (e.g., CISPR. 22). These legal requirements have created a need for all digital designers to be aware of the EMC ramifications of their design and of some fundamental EMC design considerations. Industrial companies that design and market these digital devices can no longer afford the cost and schedule delay consequences resulting from their digital designers being unaware of EMC design principles. Consequently, the subject of EMC is now being viewed by the industrial world as being an important component of an undergraduate electrical engineer’s education.”
Below is the table of contents from the Experiments Manual to give you an idea of the breadth of material included. Many of these topics are still essential today to EMC engineers and technicians!
Format of Submitted Experiments
Crosstalk in Cables
Ground Noise in Digital Logic
Rusty Bolt Demonstrator
Noise Measurement by Induction
The Thinking Engineer’s Voltage Measurement
The Effect of Circuit Impedance on
Magnetic-Field Coupling of Current Loops
Effect of Pulse Rise/Fall Time on Signal Spectra
Electromagnetic Leakage Through Seams
Common-Mode Currents and Radiated
Emissions of Cables
The contributors to the Experiments Manual noted on page 4 included a “who’s who” in the EMC community: Clayton Paul, Tony Nasuta, Henry Ott, Raymond F. Elsner, Douglas C. Smith, Andy Marvin, Thomas A. Jerse, Jasper J. Goedbloed, and Richard C. Mohr (as listed in this order).
In short, the EMC Society’s Experiments Manual is an interesting document; if you would like to learn more about it, please contact the current chair of the EMC Society’s Education and Student Activities Committee, Tom Jerse. His contact info may be found on page 3 of this Newsletter.
Back to the University of Michigan-Dearborn, you can read about the impact the Experiments Manual had on student Chris Semanson starting on page 43.
Many thanks are due to Henry Ott and Clayton Paul, as well as to all the contributors, for their collective efforts in bringing the EMC Experiments Manual to life in 1987. Thanks also to Mark Steffka for the renewed interest in this document in 2010, for encouraging his student to write an article for the Newsletter, and for providing the cover photo!
By the way, speaking of Dr. Paul, you might be interested to read his latest technical contribution in this issue of the Newsletter. His paper on partial inductance starts on page 34.
I hope you enjoy this cover story and the entire issue. It is full of interesting articles and practical papers. As always, your comments are welcomed and encouraged! EMC