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Editorial - Engineering Enrollments Down Sharply

The origin of the phrase "Everything old is new again" is credited to everything from the Bible to Shakespeare to Mark Twain. It might be one of the most oft-repeated statements. The topic of this editorial from a 1972 issue of Popular Electronics is a prime example of why people like me invoke the aforementioned dictum. For as long as I have been aware of the state of engineering and technology, opinion writers (aka "journalists"), have lamented the sorry state of education in that it cannot motivate and produce a qualified new crop of replacement engineers, scientists, technicians, doctors, nurses, chemists, and other white collar workers (I can't recall ever hearing of lawyer shortage, unfortunately). Looking back at how the "shortages" have been handled ...

AC Battery Incorporates a Biode

No, it's not a practical joke, after all, it won a NASA award. An AC battery really has been invented - sort of. Although not much detail is provided, it appears this "AC" battery is basically two batteries back-to-back with a "biode" betwixt them and a semiconductor switch that cycles from positive to negative polarity. The diagram indicates a sinewave, but maybe it's a squarewave or something in-between. It's pitched as the second coming of batteries. It would be nice to have such a device available, but will the reliability be as good as existing DC cells given the added complexity? Time will tell.

Free Engineering Magazines & Whitepapers

Lots of new titles are included this month. Engineering whitepapers, pamphlets, books, magazines, and chapter examples listed here are a small sample of a lot of new items that are offered for FREE through TradePub. The publishers make them available to qualifying people as a promotional campaign for their full line of offerings. Free e-books like "Maximizing LinkedIn for Business" and "20 Questions You Should Never Ask in an Interview" are examples. Magazine titles include Microwave Engineering Europe, Electronic Design, and Microwave Product Digest ...

Electronic Component Checking (L, C, and R)

When this article on component (resistor, capacitor, and inductor) measurement was written, readily available, inexpensive multimeters were not in existence. For about $20 you can now buy a brand new handheld DMM that will make very accurate resistance measurements and reasonably good capacitance measurements at frequencies up to a few MHz, where lead inductance starts to be significant (test frequency is usually only a few kHz). Finding an affordable, accurate inductance meter is another story. Cheap LCR meters can be purchased on eBay, but don't be surprised if the quality is not very good. The most accurate measurement method uses a frequency in the realm of actual operation, and this article ...

Custom MMIC Intros a GaAs DC - 20 GHz Distributed Amplifier

Custom MMIC is proud to introduce a new GaAs Distributed Amplifier operating in the popular DC - 20 GHz frequency range, targeting Instrumentation and EW applications. The CMD244K5 offers very flat gain and low noise figure across the band. This MMIC also has high P1dB and IP3, yielding a high dynamic range. All this performance is neatly integrated in a small 5mm x 5mm plastic air-cavity surface mount QFN package. This new, high performance distributed amplifier continues Custom MMIC's aggressive efforts to deliver the best performing GaAs and GaN MMICs in the industry ...

The Growing Problem of Space Debris

"For sixty years, humans have been launching things to space, giving rise to the problem of 'space junk.' If something isn't done about it soon, the situation is going to become very messy! In 1958, the Space Age officially began with the launch of humanity's first artificial satellite - known as Sputnik 1. Constructed and orbited by the Soviet Union, this satellite was a simple technology demonstrator designed to emit radio pulses. However, the impact its deployment had was much more far-reaching than that. Not only was this a pivotal moment in the history of human spaceflight, and a big scare for the West, it was also the first of thousands of satellites to be launched from Earth ..."

Triad RF Systems: RF/Microwave Amplifiers and Amplifier Systems

Triad RF Systems designs and manufactures RF power amplifiers and systems. Triad RF Systems comprises three partners (hence 'Triad') with over 40 years of accumulated knowledge of what is required to design, manufacture, market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA, bi-directional, and frequency translating amplifiers are available, in formats including tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology partner than a vendor for our line-of-sight communications product line." Please check to see how they can help your project.

Channel Master Antenna Advertisement

Channel Master is one of the few television and FM radio antenna companies that has survived the evolution from over-the-air (OTA) broadcasting to cable-based and then Internet-based broadcasting. Up until around the end of the last century - which is incredibly two decades ago - a large number of people still relied on rooftop and set-top antennas for program reception. Airwaves continued to get more crowded both due to additional stations being built and the ambient noise level increasing due to many other lower power devices in use. An increasing number of manmade obstacles that blocked and/or reflected signals resulted in many more low signal strength pockets and areas plagued by multipath signal variability compounded the problem ...

Transformative Electronics Systems to Broaden Wearable Apps

"Imagine a handheld electronic gadget that can soften and deform when attached to our skin. This will be the future of electronics we all dreamed of. A research team at KAIST says their new platform called 'Transformative Electronics Systems' will open a new class of electronics, allowing reconfigurable electronic interfaces to be optimized for a variety of applications. A team working under Professor Jae-Woong Jeong from the School of Electrical Engineering at KAIST has invented a multifunctional electronic platform that can mechanically transform its shape, flexibility, and stretchability. This platform, which was reported in Science Advances, allows users to seamlessly and precisely tune its stiffness and shape ..."

Transistor Terminology

Many years have passed since I sat in a college classroom to learn about transistor fundamentals. The industry had long moved past germanium transistors and was solidly into silicon. Having been formally introduced to transistors in the USAF, I was familiar with their functionality from a technician's perspective of checking for gain, proper bias (as indicated on "educated" schematics), and determining go-no-go health by performing a front-to-back resistance measurement using an ohmmeter. Holes, energy bands, gate widths, and doping levels were first encountered in solid state physics class, however. This article does a nice job of introducing the terms and concepts at a layman's level. I actually found the vacuum tube circuits in our radar unit easier ...

Berkeley Nucleonics Needs an Electronics Technician

Berkeley Nucleonics Corporation (BNC) is an established test equipment company having served the industry for 55 years. With headquarters in San Rafael, CA, Berkeley Nucleonics is looking for an Electronics Technician for test & measurement equipment with component level experience. Job requires troubleshooting and calibration of analog and digital designs, as well as some high voltage circuitry. Duties and responsibilities include: Repair, test, and calibrate TTL pulse and delay generators with considerable analog circuits, RF signal generators, microwave receivers, spectrum analyzers, some laser and high voltage work. Provide technical support to customers through email and phone ...

Veterans Day 2019: A Pittance of Time

This is my annual Veterans Day tribute. On November 11 (the 11th day of the 11th month), at 11:00 am (the 11th hour), we observe 2 minutes of silence in honor of countrymen who "gave the last full measure of devotion." A Pittance of Time is performed by Canadian citizen Terry Kelly (he went blind at an early age). It was written after an experience he had on Veterans Day in 1999. It is done in the finest Celtic tradition.

everythingRF: Their Name Says It All

Please take a few moments to visit the everythingRF website to see how they can assist you with your project. everythingRF is a product discovery platform for RF and microwave products and services. They currently have 227,460 products from more than 1210 companies across 285 categories in their database and enable engineers to search for them using their customized parametric search tool. Amplifiers, test equipment, power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers, power supplies, and everything else. Please visit everythingRF today to see how they can help you.

RF Cafe Radio Engineering Veterans Day Crossword

Each week, for the sake of all avid cruciverbalists amongst us, I create a new technology-themed crossword puzzle using only words from my custom-created lexicon related to engineering, science, mathematics, chemistry, physics, astronomy, etc. This one for November 10, 2019 celebrates Veterans Day. You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, see someone or something in the exclusion list who or that is directly related to this puzzle's theme, such as Hedy Lamarr or the Bikini Atoll, respectively ...

Mercury Transit on Monday, November 11

Mercury will pass across the face of the sun. The astronomical term is "transit." What makes this transit of Mercury so spectacular is that it passes nearly in the center of the sun. It will take Mercury approximately 5-1/2 hours to move from the eastern edge to the western edge, from 7:35 am to 1:04 pm EST. Both the sun and the moon subtend an angular width of about half a degree. Of course will should never look directly at the sun with your naked eyes, and particularly not with any sort of magnification, be it binoculars or a telescope. The safest way to observe this Mercury transit it by using a white projection screen with any telescope generate an image large enough to make the black dot of Mercury stand out relative to the sun. Weather permitting, I'll have my 1969 era 60 mm Sears Model 6305A refractor set up. The next transit of Mercury will be in 2032!

Carl and Jerry: The Bell Bull Session

You wouldn't know it from the title, "The Bell Bull Session," but this Carl and Jerry technodrama features a very interesting subject - the Shive Wave Machine. The "Bull Session" part of the title is self-explanatory; it's the "Bell" part that is a reference to Bell Telephone Laboratories, and specifically to a gentleman named Dr. John N. Shive, who was Director of Education and Training there. Being avid amateur radio operators and electronics experimenters, Carl and Jerry were very familiar with the concept of traveling waves and impedance matching. The Shive Wave Machine is an ingenious device that provides a visual physical representation of a traveling wave and how an impedance mismatch generates ...

Airwave Advisors Added to Tech Services Listings

Airwave Advisors president and founder Nick Foster wrote asking to have his cell tower consulting company added to a few RF Cafe vendor pages (Antennas, Technical Services, Wireless). According to his website, "We are the nation's leading cell tower lease experts and the only accredited cell tower lease consulting company in the United States to hold an A+ rating with the BBB. We assist private landowners, commercial real estate owners, municipalities, and anyone else who either has a cell tower lease, or has been contacted for a new cell tower lease." This might be a good resource for cell planners. Airwave Advisors is located in Carlsbad, CA, and can be reached at 858-216-2649.

IEEE WIE Forum USA East 2019

IEEE WIE Forum USA East 2019, being held in Arlington, VA, from November 21st to 23rd, "focuses on developing and improving leadership skills for individuals at all stages of their careers. Attendees will have the opportunity to hear inspirational and empowering talks presented by successful leaders from IEEE Northeast. Emerging technologies will also be demonstrated, engaging attendees to facilitate discussion and potential advancement of STEM outreach class ideas." Programs motivate positive progress in career and life, help advance career, life, leadership, team and career management. Workshops on skills and concepts for STEM pre-university outreach, and a career fair will be held for students and professionals ...

Custom MMIC Intros 3 New Wideband Double Balanced Mixers

Custom MMIC continues the rapid expansion of its standard product portfolio with three new additions to its GaAs MMIC mixer portfolio. The CMD312, CMD313 and CMD253 are wideband GaAs double balanced mixers, operating from 4 to 28, 6 to 45 and 6 to 14 GHz respectively. These new MMICs are intended to support emerging wide bandwidth applications in Test Equipment, Instrumentation, Aerospace and Defense. All three mixers feature low conversion gain and high isolation performance. They are offered in die form, with a packaged version already available in the CMD253 and planned for the CMD312 and CMD313 ...

Electroadhesive Stamp to Maneuver Microscopic Structures

"A team of researchers from the Massachusetts Institute of Technology (MIT) has devised a way to pick up and manipulate extremely small electronic components found in cutting-edge technology. Using a tiny 'electroadhesive' stamp, researchers can now pick up and put down objects that are as minute as 20 nanometers wide. That’s roughly 1,000 times finer than a strand of human hair; this technology could prove extremely useful as the components in our devices get smaller and smaller in size. The high-tech stamp is made from an assortment of ceramic-coated carbon nanotubes. The tubes are placed so they stick up, like the bristles found in a toothbrush. A small voltage is sent through the stamp ..."