A colleague, Mike Stasiowski, and I came up with this quick GHz wavelength formula while designing quad ridge circular polarized jamming antennas for the military when working at Nurad. The textbook formula (wavelength = c/f) where: c = the speed of light 3.00×108 m/s, and f = frequency in Hz, was cumbersome at times to calculate, then convert, to inches for practical … [Read more...]
Antenna Factor Calculations and Deviations
Introduction In recent years, the use of a term call "Antenna Factor" in EMC and spectrum pollution work has become very important. There has been a great need for measuring field intensity and/or power density as accurately and conveniently as possible. Classically in RFI/EMI measurements, the use of antenna factors is very common. These antenna factors were, by … [Read more...]
Shielding Design Flow Chart
The flow chart in Table 1 will assist the designer in selecting the appropriate shielding options necessary to meet their shielding and environmental requirements. The shielding requirement flow chart begins by identifying the type of NEMA or IP enclosure based on the intended environment (indoor/outdoor, military/commercial, marine or land/desert). Then, using the resulting … [Read more...]
Some of the Many Stories of Medical EMI
Introduction I have been collecting stories about EMI for a long time, publishing many of them in the ‘Banana Skins’ column of The EMC Journal, www.theemcjournal.com. Some come from official reports, some from anonymous whistleblowers, some are amusing, and some concern deaths and injuries. At the present time, I have published 855 of them, all indexed by application and by … [Read more...]
EMI Basics and Board Level Shielding Design
Introduction In today’s world full of digital electronic devices, electromagnetic interference (EMI) is a major concern in both military and commercial marketplaces. Electrical equipment can become susceptible to these undesirable emissions and malfunction due to their presence. The simplest and most cost-effective method for reducing EMI is to first attack it at the board … [Read more...]
Guide to Real-Time Spectrum Analyzers: Applications
This is Part 4 in a series of articles which review the basics of conventional swept versus real-time spectrum analyzers and highlight some of the recent advances and instrument form-factors. Read Part 1, Guide to Real-Time Spectrum Analyzers: Types, here. Read Part 2, Guide to Real-Time Spectrum Analyzers: Definitions, here. Read Part 3, Guide to Real-Time Spectrum … [Read more...]
Guide to Real-Time Spectrum Analyzers: Advantages of Swept Versus Real-Time Spectrum Analyzers
This is Part 3 in a series of articles which review the basics of conventional swept versus real-time spectrum analyzers and highlight some of the recent advances and instrument form-factors. Read Part 1, Guide to Real-Time Spectrum Analyzers: Types, here. Read Part 2, Guide to Real-Time Spectrum Analyzers: Definitions, here. Swept spectrum analyzers are simpler and … [Read more...]
Can 5G Sites Be Good Neighbors?
Baseball Hall of Famer Yogi Berra was notable for his skill on the field and was equally notable for many of his quotes. “Yogi-isms” were things he often said that were both amusing and insightful. Referring to a popular restaurant, he said, “Nobody goes there anymore; it’s too crowded.” Sounds like a contradiction, but it’s easy to follow his meaning. Customers chose not to … [Read more...]
Drag Races, a Cashless Society, and the Threat of EMP
About a month ago, my 12-year-old son and I made his first-ever trip to the NHRA Drag Races near our home. It’s something that I always did with my dad, and I have looked forward to taking him ever since he was born. It’s a typical father-and-son day, wrought with loud, fast cars, terrible food, and the occasional waft of nitromethane fuel in the air. The drive is about … [Read more...]
Static Control Resilient Flooring Qualification Procedures Ensure Space and Defense ESD Compliance Pt. 2
This article is the second and final part of Static Control Resilient Flooring Qualification Procedures Ensure Space and Defense ESD Compliance. Read Part 1 here. ANSI/ESD STM97.2 This critical standard test method attests to the static control resilient flooring’s ability to minimize charge buildup and provides the user with traceable data to assign a voltage flooring … [Read more...]
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