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4 of the December 2018 homepage archives.
Ham Comics: There's One in Every Crowd
It's the Friday before Christmas vacation and nobody is thinking about work. If you are stopping by RF Cafe to kill time until the boss lets you go home (early, preferably), thanks for thinking of us. Not that you really need something to get you in a festive mood, but here are a few funny amateur radio-themed comics from a 1966 issue of Popular Electronics magazine, compliments of artist Buz Holland. When I saw the comic with the parrot squawking CQ while including his call sign - WA4YKK - my first thought was to check the FCC's Universal License System (ULS) to see to whom it belongs, and then I realized it was the artist's ...
Engineers Have High Hopes for Economy
Part 4 of Electronic Design's2018 Salary & Career Survey covers engineers' attitude about the economic outlook of the nation. "More than 60% of respondents to Electronic Design's latest annual Salary Survey have positive feelings about the status of the United States economy, while around 15% feel negatively about it. Another 25% of the more than 1,300 survey respondents say they have no strong opinions about it either way. Only 3% harbor very negative feelings about the overall economy. Electrical engineering represents one of the economy's main engines. Semiconductor firms that supply parts for all sorts of products are monitored for clues about the future of the American economy. The Trump administration has had electronic devices in its crosshairs as it attempts to close a trade imbalance with China ..."
Coil Function Quiz
Here is a quick, 10-question electronics-themed quiz about coils (inductors). It appeared in the June 1962 edition of Popular Electronics magazine. Don't be scared off by the vacuum tubes that appear in three drawings. Just pretend they are transistors - it won't affect your answers. One of the coil applications is almost obsolete for most people as the nature of computer monitors and TV screens has changed significantly in the last decade ...
Navigating the 5G NR Standards
Sheri DeTomasi, of Keysight Technologies, has an article titled "Navigating the 5G NR Standards" on the Microwave Journal website that is an introduction to the increasingly complex topic of wireless communications. Says Ms. DeTomasi "Approximately once each decade, wireless communications standards have marched forward, advancing through 2G, 3G, 4G and now moving into 5G. The 5G New Radio (NR) standard creates a whole new era of wireless communications. The promise of everything connected, all the time, with extremely fast download speeds and ultra-low latency will require massive changes across the 5G ecosystem. The 5G NR standard adds new operating bands with advanced ways to package and transmit signals. mmWave operating bands, wider modulation bandwidths, scalable numerologies ..."
Reindeer Really Do Know How to Fly!
For the past many years, videos have been posted that confirm to all the Doubting Thomases out there what "The Christmas Song" songwriters Bob Wells and Mel Tormé (popularized by Nat King Cole) asserted. This story qualifies as a high tech subject due to the FHSS / DSSS techniques in the 2.4 GHz ISM band radio systems, and brushless motors using LiPo batteries. Merry Christmas to All, and to All a Good Night!
TotalTemp Technologies: Thermal Platforms for −100°C to +200°C
TotalTemp Technologies has more than 40 years of combined experience providing thermal platforms. Thermal Platforms are available to provide temperatures between −100°C and +200°C for cryogenic cooling, recirculating circulating coolers, temperature chambers and temperature controllers, thermal range safety controllers, space simulation chambers, hybrid benchtop chambers, custom systems and platforms. Manual and automated configurations for laboratory and production environments ...
Shape-Shifting Origami Helps Antennas Adapt on the Fly
"Researchers at the Georgia Institute of Technology have devised a method for using an origami-based structure to create radio frequency filters that have adjustable dimensions, enabling the devices to change which signals they block throughout a large range of frequencies. The new approach to creating these tunable filters could have a variety of uses, from antenna systems capable of adapting in real-time to ambient conditions to the next generation of electromagnetic cloaking systems that could be reconfigured on the fly to reflect or absorb different frequencies. The team focused on one particular pattern of origami, called Miura-Ori, which has the ability to expand and contract like an accordion ..."
Electricity & Physiology
The subtitle of this article from a 1971 issue of Popular Electronics, "From Quackery to Speculation to Programmed People," could to some extent still be applicable even though the author evidently meant to put an end to the "quackery" and "speculation" part of it. Indeed, a lot of advancement has been made in the fields of electrostimulation of weak or/or paralyzed muscles, healing of certain types of soft and hard tissues, suppressing sporadic muscle twitching and epileptic seizures, and other malady diagnosis and relief. Specifically tuned microwave frequencies have proven useful in healing and symptom relief as well. As with most articles on medical procedures, I cringe at some of the photos, like the "skin tunnel transformer" where an implanted subcutaneous coil ...
Wanted: Vintage LEDs for Historical Display
Website visitor Joshua Albright wrote to say he is assembling a historical display of LEDs and wonders whether anyone out there has examples from the 1960s through early 1980s. In particular, Monsanto, General Electric, Texas Instruments, [Thorn], and Fairchild are the manufacturers he's most interested in obtaining. "The things I typically look for [to identify age] are the can construction, gold plated leads, epoxy with bubbles in it, and the lousy light output the early LEDs had." Mr. Albright is offering to pay for useful LEDs and/or shipping costs if needed. If you are able to help, please send me an e-mail here at RF Cafe and I will put you in touch with him. Thanks for your help.
An Introduction to Interference Hunting
Rohde & Schwarz (R&S) has a pretty nice white paper out titled, "An Introduction to Interference Hunting," which is free for downloading (I always try to find links that do not require registration). It goes through basic techniques of using a directional antenna for tracking down signals of interest. R&S actually has quite a bit of information on interference location with their "iHunter Training Program" whereby you can become a certified Interference Hunting Professional. Online training videos are also available from R&S ...
"Technically, panoramic reception is defined as the simultaneous visual reception of a multiplicity of radio signals over a broad band of frequencies. In addition, panoramic reception provides an indication of the frequency, type and strength of signals picked up by the receiver. Deflections or 'peaks' appearing as inverted 'V's on the screen of a cathode-ray tube." It is the kind of display that radar operators at Pearl Harbor were using when they mistook wave of incoming Japanese bombers a squadron of B-17s from the mainland. The panoramic receiver is not a wartime development, experimental models having been produced just prior to the outbreak of war. However, the many uses to which it has been put have demonstrated that the panoramic idea, particularly in the form of adaptors which may be connected to any receiver, is going to be very important ...
Neil Carleton, VE3NCE, Named to Canadian Amateur Radio Hall of Fame
Check this out: Mr. Neil Carleton, VE3NCE, has been inducted into the Canadian Amateur Radio Hall of Fame. Neil contacted me early this year requesting that I post a notice of the upcoming auction for his immense radio-themed postage stamp collection, which was a life-long passion. "Radio Amateurs of Canada (RAC) says the honor recognizes radio amateurs' 'outstanding achievement and excellence of the highest degree, for serious and sustained service to Amateur Radio in Canada, or to Amateur Radio at large.' RAC said Amateur Radio played an important role during Carleton's teaching career, and he was a key advisor in developing the RAC Youth Education Program, aimed at introducing Amateur Radio in the classroom. Carleton is a member of the Almonte Amateur Radio Club ..."
Transient Specialists: EMC, EMI, RFI Test Equipment Rentals
Transient Specialists specializes in EMC test equipment rentals and carries a complete line of ESD guns, surge immunity test equipment, and EFT generators. Rentals available for military (Mil-Std 461), automotive (ISO 7637), and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited calibrations and technical support on EMC testing equipment offered. Equipment consists of top EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and EMC Partner ...
Topological Material Switched off & on for 1st Time
"Over the last decade, there has been much excitement about the discovery, recognized by the Nobel Prize in Physics only two years ago, that there are two types of insulators: normal insulators which don't conduct electricity, and topological insulators - newly discovered materials that conduct electricity only on their edges. Now, FLEET researchers at Monash University, Australia, have for the first time successfully 'switched' a material between these two states of matter via application of an electric-field. This is the first step in creating a functioning topological transistor - a proposed new generation of ultra-low energy electronic devices. Ultra-low energy electronics such as topological transistors would allow computing to continue to grow, without being limited by available energy as we near the end of achievable improvements in traditional ..."
National Company Christmas and New Year Greeting
Take a look at the list of National Company's employee list wishing their customers a Merry Christmas and a Happy New Year. Every one of them is a licensed Ham radio operator. It appeared in the January 1941 issue of QST, but was for the 1940 Christmas. National Company was a major producer of amateur radio gear in the day. Little did they suspect that by the same time a year later, America would be newly engaged in World War II after the Japanese attack on Pearl Harbor on December 7, 1941. Interestingly, the American Lung Society's Christmas Seals stamp that appears in the upper left corner is authentic and must have been applied by humans. That means thousands of copies had to be manually stamped before mailing ...
Just in Time for Christmas Package Thieves: A Glitter Bomb
This video has gotten more than 25 million views in just two days. NASA engineer Mark Rober decided to reward the human debris who steal packages from people's porches. His Glitter Bomb is a technical marvel of CAD design, 3−D printing, smartphone GPS location tracking and video streaming, custom PCB, mechanization, and microprocessor control. You'll have a great laugh at watching the reactions of low life scum who take the bait. GPS tacks the perp, and then when he / she opens the box a swirling mass of multicolor glitter is spewed all over the place. As if that is not enough, a few seconds later Fart Gas (redundant?) is sprayed to enhance to mood during clean-up of the glitter mess. Mr. Rober is no newcomer to such pranks, as his other videos show. I'm surprised he hasn't been sued yet. Surely there's an ambulance chaser out there looking for an easy buck - and a deranged judge to match ...
Anatech Electronics offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. Anatech has introduced three new filter designs: a 10-1000 MHz, 2-way power divider with SMA connectors, a 113 MHz bandstop / notch filter with SMA connectors, and a surface mount, 5000 MHz ceramic bandpass filter. Custom RF filters designs are used when a standard cannot be found, or the requirements are such that a custom approach is necessary ...
Klystron: Tube for Outer Space
If you have been in the RF and microwaves business for any length of time, you are probably familiar with a company named Varian. In the days before you did your parts shopping online, Varian catalogs populated the desks and bookshelves of many RF engineers who worked in the radar field, including mine. Did you know that it is named after the brothers Russell and Sigurd Varian, who started the business in 1948 to market their high power klystron tubes? Following a number of reorganizations, it was purchased by Agilent technologies in 2010. This story from Radio Electronics magazine does a real nice job explaining the workings of a klystron without getting too deep into the gory theoretical detail ...
Nova Microwave: RF & Microwave Circulators & Isolators
Nova Microwave is a leader in technically differentiated electronic and radio frequency Ferrite Circulators and Isolators that connect, protect and control critical commercial and military wireless telecommunications systems. Our staff is dedicated to research and development of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz to 26.5 GHz. Please visit Nova Microwave today ...
Researchers Perform Analog, Wave-Based Computations Using Wi-Fi Signals
"A pair of French researchers have developed a way to use ordinary Wi-Fi signals to perform analog, wave-based computations. Researchers, Philipp del Hougne and Geoffroy Lerosey, from Langevin Institute and the company Greenerwave, have described their experiments and what they represent, in their paper published in the journal Physical Review X. Computers represent information digitally, in ones and zeroes - but back in the early days of computing, there was discussion regarding the possibility of using analog processors. Even then, it was clear that such an approach would be less energy-intensive. But digital won out, and the rest is history. But that might not be the end of the story. As hardware engineers begin to run headlong into the limitations of Moore's Law, some engineers have begun ..."
Ulano Masking Films - Rubylith
Raise your hand if you're old enough to remember doing printed circuit board layout using Rubylith tape. My hand is up. Back in the early 1980s, I did prototype PCB designs in an engineering development lab at Westinghouse Electric's Oceanic Division. Most of it was for analog and RF substrates that would be photographically reduced in size for use with bare integrated circuit die and surface mount passive components (Rs, Ls, and Cs), upon which I would later epoxy-mount those components and wire-bond everything using 1−mil gold wire. However, there were projects where full-size leaded components were used on a through-hole PCB that used not only the Rubylith tapes but also sheets with special electronics shapes for solder pads around the holes for components leads, ground and power planes, board-edge connectors ...
Chip with Micro-Hotplate for Self-Healing and Sustainable Electronics
"This invention is an on-chip immune system against hot-carrier stress, bias temperature instability, and total ionizing dose degradation. Ames Research Center, Moffett Field, California Heat treatment, also known as annealing, is a common step in the semiconductor fabrication process. A buildup of radiation-induced localized charge within the semiconductor and insulator alters local field distribution, threshold voltage, and leakage current. NASA's patent-pending technology implements an annealing process on a system level directly on a chip for annealing defects and improving device performance with heating done in the laboratory. The annealing may be performed inside an oven or upon a hotplate ..."
Please Visit Triad RF Systems to Thank Them for Their Support
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 we can help your project ... Please check to see how they can help your project ...
Too-Small Cubicles: 1932 "The Wireless World" Article
As the old saying goes, "The more things change, the more things stay the same." Incredibly, back in 1931 people were complaining about shrinking office cubicle sizes. To wit: "At 'Broadcasting House' rooms measuring 8ft. x 6ft. are being coveted by the many people who will be condemned to labour in cubicles 7ft. x 5ft. The Civil Engineer himself, who helped to design and erect the building, works in a compartment in which, as the American said, 'You couldn't cuss a cat without getting hair on your teeth.'" ...and whoa!, dig this statement by the author regarding the demise of "local oscillators" in the UK (noisy regenerative Rx LO interference): "Steps might be taken to ensure the survival of a few specimens, perhaps by the founding of a national reservation similar to those which accommodate the Red Indians in America. The few remaining squealers and their ..."
PCB Directory is the largest directory of Printed Circuit Board (PCB) Manufacturers, Assembly houses, and Design Services on the Internet. We have listed the leading printed circuit board manufacturers around the world and made them searchable by their capabilities - Number of laminates used, Board thicknesses supported, Number of layers supported, Types of substrates (e.g., material, flexible, rigid), Geographical location, and more ...
Topological Matters: Toward a New Kind of Transistor
"Billions of tiny transistors supply the processing power in modern smartphones, controlling the flow of electrons with rapid on-and-off switching. But continual progress in packing more transistors into smaller devices is pushing toward the physical limits of conventional materials. Common inefficiencies in transistor materials cause energy loss that results in heat buildup and shorter battery life, so researchers are in hot pursuit of alternative materials that allow devices to operate more efficiently at lower power. Now, an experiment conducted at the U.S. Department of Energy's Lawrence Berkeley National Laboratory has demonstrated, for the first time, electronic switching in an exotic, ultrathin material that can carry a charge with nearly zero loss at room temperature ..."
Meet Mr. FET ... the Transistor That Thinks It's a Tube
Yesterday was the 71st anniversary of the announcement of the transistor's invention by Drs. Shockley, Bardeen, and Brattain at Bell Labs, but it was a Sunday so not as many RF Cafe visitors saw the commemorative title graphic I used. Their transistor was a current-controlled signal amplifying device as opposed to the field-effect transistor (FET) which is a voltage-controlled signal amplifying device - as is the vacuum tube. I never thought about it before, but maybe that had something to do with the electronics world's hesitancy to adopt the transistor as a replacement for the tube. Early in the transistor's history, practical applications were limited due to low reliability, low power handling, low frequency, lack of ruggedness in harsh operating conditions, and other shortcomings compared to established and much refined vacuum tubes was reason enough to shun the newfangled technology, but that current-controlled thing ...
5 Ws of Spray-on Antennas
"Spray-applied MXene antennas could open the door for new applications in smart technology, wearables, and IoT devices. This method sprays invisibly thin antennas - made from a type of two-dimensional metallic material called MXene - that perform as well as those being used in mobile devices, wireless routers, and portable transducers. MXene titanium carbide can be dissolved in water to create an ink or paint. The exceptional conductivity of the material enables it to transmit and direct radio waves, even when it's applied in a very thin coating. Even transparent antennas with thicknesses of tens of nanometers are able to communicate efficiently. The thinnest antenna was 62 nanometers ..."
Lenny & the Squigtones - "The Jolliest Fat Man"
Most people who were around in the 1970s remember the sitcom "Laverne & Shirley." It was popular as a part of the whole 1950s renaissance that was happening with shows like "Happy Days," "Grease," "American Graffiti," et al, that captured the attention of the parents of we teenagers as well as weselves [sic]. I was being held against my will at Southern Senior High School at the time, and many of the kids adopted a "greaser" lifestyle that included cigarette packs rolled up in t-shirt sleeves and Brylcreem in the hair (mainly just the guys), leather jackets and Keds high-top sneakers (guys and gals), and poodle skirts and saddle Oxford shoes (mainly just the gals). Two weirdo characters, Lenny and Squiggy, made cameo ...
At the 1929 Radio World's Fair
You've heard of the World's Fairs, the most familiar probably being the 1933 Chicago World's Fair where the theme was "A Century of Progress." World's Fairs have been held in various cities worldwide since the late 1790s. In 1929, the World's Fair was held in the United Kingdom, but the "Radio World's Fair," which began its annual run in 1924 (click on stamps thumbnail), was held in New York City. Surprisingly little exists on the Internet about the events. It was more of a trade show to introduce new products than it was a fair, as can be seen from the photos. Radios with decorative wooden cabinets were becoming popular as the number of commercial broadcast stations was growing rapidly. Remote control in the day meant a handheld unit with a cable attached to the main system. Crosley introduced its first gendered radio model - the Monotrad ...
Empower RF Systems: RF & Microwave Power Amplifiers
Empower RF Systems is a global leader in power amplifier solutions. Empower RF Systems is an established and technologically superior supplier of high power solid state RF & microwave amplifiers. Our offerings include modules, intelligent rack-mount amplifiers, and multi-function RF Power Amplifier solutions to 6 GHz in broadband and band specific designs. Output power combinations range from tens of watts to multi-kilowatts. Unprecedented size, weight and power reduction of our amplifiers is superior to anything in the market at similar frequencies and power levels ...
RFID Patent Enables Increased Bit Density & Lowering Costs of Tags
"Vubiq Networks has filed its fourth millimeter wave RFID patent application with the U.S. Patent and Trademark Office. The application is entitled System and Method for High-Bit Density Millimeter Wave Chipless RFID and has been assigned the application number 62775479. The patent application defines advanced, high-bit density chipless RFID technology using the company's polarimetric synthetic aperture radar (SAR) technique that incorporates polarization and phase detection. The technology will provide orders of magnitude higher bit density for RFID tags as compared to 'prior art' or other competitive approaches. The application, which is the fourth RFID patent ..."
RF Cafe Engineering & Science Crossword Puzzle December 16
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. 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. This week's crossword contains a shameless plug for my custom software products - they're inexpensive and will save you a lot of time ...
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