Homepage Archive - December 2020 (page 2)

Monday 14

Magnetic Current - Discovery of the Age?

It was a big deal in 1944 when Austrian physicist Dr. Felix Ehrenhaft announced that he had discovered "magnetic charges," aka magnetic monopoles. He claimed based on numerous kinds of experiments that a reversible "magnetic current" existed around current-carrying conductors. It seems based on my reading of this Radio-Craft article that he believed there existed mono-magnetic particles of some sort analogous to electrons and protons. Later experiments seems to indicate that high intensity light beams could also produce evidence of magnetic currents. Dr. Ehrenhaft widely promoted his conclusions and invited doubters to examine his apparatus. Based on some Web searches on the topic, independent researchers were not able to reproduce his findings, so his work eventually faded into the background. Some credit his experiments with light for demonstrating the particle nature of light's ability to accelerate masses. The most profound implication of proving the existence of magnetic monopoles...

Combining Light & Sound to See Underwater

"Stanford University engineers have developed an airborne method for imaging underwater objects by combining light and sound to break through the seemingly impassable barrier at the interface of air and water. The researchers envision their hybrid optical-acoustic system one day being used to conduct drone-based biological marine surveys from the air, carry out large-scale aerial searches of sunken ships and planes, and map the ocean depths with a similar speed and level of detail as Earth's landscapes. Their 'Photoacoustic Airborne Sonar System' is detailed in a recent study published in the journal IEEE Access..."

The Field That Stays at Home

Here is a really good introductory article on electromagnetic (EM) fields as they pertain to inductors, transformers, and antennas. It appeared in the April 1942 edition of QST magazine. The FCC had only been in existence for eight years at the time and was pretty much just figuring out how to regulate the heck out of everything. The author discusses compliance issues for these newfangled RF devices that were becoming more and more numerous. Interestingly, the first sentence says, "Every time you threw the transmitting switch in pre-war days...," bringing to mind how the Feds banned Amateur Radio during most of World War II for security reasons as well as to assure that scarce resources went toward building and servicing military gear as needed. Many Hams offered their gear either as a donation...

RF Cascade Workbook 2018

RF Cascade Workbook 2018 is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. Chances are you have never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed. An intro video takes you through the main features...

Millions of Britons Do Not Know About These British Inventions

Millions of Britons do not know the internet, the colour television and jet engine are British inventions, a survey has claimed. Around half of 2,000 adults polled were not aware that London based Sir Tim Berners-Lee created the World Wide Web in 1989. 55% did not realise John Logie Baird, of Dunbartonshire, was the first person to demonstrate a working colour television in 1928. And 51 per cent did not know Frank Whittle from Coventry made the very first jet engine having patented the invention in 1928. 'For the last 50 years the award has celebrated ground-breaking engineering innovations that have established the UK as a global leader,' said Dr Dame Sue Ion DBE, chair of the Royal Academy of Engineering..."

Many Thanks to Withwave for Continued Support!

Withwave manufactures an extensive line of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch, board edge, panel mount), calibration kits (SOLT), a fully automated 4-port vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures for calibration and multicoax cable assemblies. Frequency ranges from DC through 110 GHz. Please contact Withwave today to see how they can help your project succeed.

Sunday 13

Electronics Theme Crossword Puzzle for December 13th

For the sake of avid cruciverbalists amongst us, each week I create a new crossword puzzle that has a theme related to engineering, mathematics, chemistry, physics, and other technical words. This December 13th Electronics Theme crossword puzzle, as always, contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

Friday 11

Allied Radio: Hallicrafters Receivers

Little did Ham radio operators know in April of 1941 when they were enthusiastically buying equipment for their shacks that a year later the Federal Communications Commission (FCC) would ban them from broadcasting from their transmitters. This advertisement for a high-end Hallicrafters receiver appeared in the April issue of Radio News magazine. Part of the feature definition includes "calibrated bandspread inertia controlled," and "micrometer scale tuning inertia controlled." I'm not sure what the "inertia controlled" part is, unless it refers to how massive metal disks were sometimes installed inside the chassis on the tuning shaft in order to give a more solid feel to the control knob, as well as to enable the dial to be spun and released to rapidly move through a large distance between adjustment points...

VNA Master Class: Effective Use of VNA "Channels" for Efficient Measurement and Analysis

"Copper-Mountain-Technologies-VNA-Master-Class-Channels-Efficient-Measurement-12-9-2020.htm" target="_top"> Copper Mountain Technologies (CMT), a leading developer of innovative RF test and measurement solutions for engineers all over the world, will present a free webinar titled "Effective Use of VNA 'Channels' for Efficient Measurement and Analysis." Tune in on Tuesday, December 15th, at 11:00 AM EST. The webinar is free, and you can dial in for interactive participation. CMT Senior RF Design Engineer Brian Walker will be your host as he describes how "Channels" on a VNA are a very effective way of making a series of complex measurements simultaneously. Often it is important to visualize a number of different operational parameters of a circuit while performing tuning or during production test. In this short webinar Brian demonstrates how one might effectively use two or more channels to make useful measurements. The full agenda includes allocating traces vs. allocating channels, setting up multiple channels, calibration...

50-Million-Electron Jolt Sensors Power Themselves

"With just a 50-million-electron jumpstart, sensors can power themselves for more than a year. Researchers from Washington University in St. Louis, led by Prof. Shantanu Chakrabartty, created self-powered sensors by taking advantage of a quantum effect known as 'tunneling.' For a device that relies on complex physics, the sensor is somewhat simple. The components required are four capacitors and two transistors. From these six parts, Chakrabartty's team built two dynamical systems, each with two capacitors and a transistor. The capacitors hold a small initial charge, about 50 million electrons each. The 50 million electrons are programmed in during the device initialization phase..."

Paul Harvey Honors Ham Radio Operators

"Hello Americans, This is Paul Harvey..." Radio legend Paul Harvey produced and performed a daily show that featured news, commercials, and commentary. For nearly 75 years, dedicated listeners looked forward to his show on the local AM radio stations - especially The Rest of the Story. Scores of wars, natural disasters, crises, deaths, scientific advances, miracles, and acts of human kindness were commented upon in Mr. Harvey's unique delivery style. On March 19, 2003, Mr. Harvey did a pitch for the role of Amateur Radio operators in emergency response roles. The mention was the second item on "page four" of his Paul Harvey Noon News and Comment program. "America's quiet warriors are the legion of ham radio operators, 700,000 of them, who are always at ready for backup duty in emergencies - amateur, unpaid, uncelebrated, civilian radio operators...

Modelithics & Piconics Provide 3D Models for Conical Inductors up to 67 GHz

"Modelithics-Piconics-3D-Models-Conical-Inductors-67%20GHz-12-8-2020.htm" target="_top"> Piconics and Modelithics, are pleased to announce the availability of 3D models for the CC20T44K240G5-C and CC25T47K240G5-C "Modelithics-Piconics-3D-Models-Conical-Inductors-67%20GHz-12-8-2020.htm" target="_top"> conical inductors from Piconics. Both models are included in the latest version, v20.8, of the Modelithics COMPLETE+3D Library for Ansys® HFSS™. The new models are validated through multi-substrate S-parameter measurements. Both are validated through 67 GHz, making them well suited for extremely broadband applications. The CC20T44K240G5-C and CC25T47K240G5-C conical inductors have inductance values of 0.170 and 0.250 μH, respectively. In addition, the CC20T44K240G5-C is rated for a maximum current of 325 mA, while the CC25T47K240G5-C has a maximum current rating of 230 mA. Potential use cases for the conical inductors include bias...

Please Thank PCBONLINE for Their Support!

PCBONLINE supplies complex rigid and flex-rigid printed circuit boards (PCBs)，and one-stop production with maximum flexibility ranging from prototype sample to mass production. Rigid-flex, HDI, multilayer, IC-loadboard, LCP 5G optical module, ceramic, MCPCB. Materials include Rogers, Taconic, Arlon, Isola, Bergquist, Kapton, Panasonic, and more. After more than 15 years of continuous efforts, PCBONLINE constantly updates our equipment, improves our technology, and serves you with the highest quality. Cost and delivery quotations online without the need for multiple phone call and/or e-mails.

Thursday 10

Mac's Service Shop: Soldering

Listen to the RF Cafe Podcast. It is a rare thing when I take exception (i.e., disagree) with anything Mac McGregor has to say, but on the subject of soldering I must object. In this 1956 installment of Mac's Service Shop, Mac and Barney are discussing the plusses and minuses of making a solder joint mechanically sound prior to applying solder. Barney mentions an article he read where the author asserts that the only way to make a quality solder joint is to wrap component leads and wire ends around posts, lugs, eyes, etc. and then flowing the solder. Both Mac and Barney argue that a perfectly sound solder joint can be made simply by laying the lead or wire in place and applying solder. From a servicing perspective that sounds good, because - as I can attest to from much experience...

High-Flying 5G Could Slash Network Costs

"A British company has come up with the novel idea of using a drone in the sky to provide 5G Internet to consumers and businesses, utilising an "unique lightweight, long-endurance airframe certified for civilian use" and powered by liquid hydrogen, to provide the globe's biggest airborne communications platform. Stratospheric Platforms chief executive Richard Deakin told iTWire in response to queries that the High Altitude Platform would be able to stay aloft for nine days. 'Only one HAP is required to provide the service, but some customers may want to ensure that they have a very high level of service assurance, so much of the modelling we have done assumes a spare HAP for each one on station, or a spare HAP for say three HAPS on station etc..."

Aviation World Mourns Passing of Chuck Yeager

"The first man to break the sound barrier, Chuck Yeager, and who undoubtedly had 'the right stuff,' died on December 7, 2020 at the ripe old age of 97. You can't take West Virginia out of the boy. Charles Yeager was born on February 13, 1923, in Myra, West Virginia, deep in the heart of Appalachian hill country. As a child, Yeager shot squirrels and rabbits and skinned them for the family's dinners. In September 1941, armed with his high school diploma, Yeager enlisted in the Army Air Forces, which was the precursor to today's U.S. Air Force. Yeager became an airplane mechanic. After tagging along with a maintenance officer who was flight-testing an airplane, Yeager decided to sign up for a flight training program..."

Radio Amateur Course - Resistance, Inductance, and Capacity

As mentioned many times in the past, some things never change regarding the basics of electricity and electronics. Resistance, inductance, and capacitance (termed "capacity" here) are examples and are addressed in this last of a three-part series which appeared in 1935 issues of Short Wave Craft magazine. When first starting out in this science, an effective introduction to the fundamentals can often determine whether a person sticks with it or finds another area of interest to pursue as a hobby and/or vocation. Analogous examples of voltage and water pressure, resistance and the diameter of a water hose, inertia in a spinning mass opposing a change in rate and an inductor opposing a change in current, etc., are presented along with some good sketches of the principles...

Air Force Technology Tracks Sporadic E

"Researchers at the Air Force Research Laboratory (AFRL) in New Mexico have discovered a new way to track and characterize a phenomenon called 'Sporadic E' that naturally occurs in the upper atmosphere where large structures of dense plasma form. These plasma structures, which occur at midlatitude locations around the world, disrupt radio frequency (RF) electromagnetic waves (or simply 'radio waves') and impact both DoD and civilian radio systems in positive and negative ways, depending on the application. 'Previous methods to observe these structures were insufficient for identifying and tracking these structures over large regions,' said Ken Obenberger, research physicist at AFRL. 'It would be advantageous to actively identify where these structures are, where they are going, and how dense they are and we thought we could find a better way..."

Linx Technologies Launches White Bronze N Connectors

"Linx-Technologies-Launches-White-Bronze-N-Connectors-12-8-2020.htm" target="_top"> Linx Technologies, a developer and manufacturer of antennas and connectors, is pleased to introduce a series of "Linx-Technologies-Launches-White-Bronze-N-Connectors-12-8-2020.htm" target="_top"> white bronze N-type RF connectors. Linx N connectors excel in a wide range of applications including Internet of Things (IoT), cellular IoT (LTE-M/Cat-M1 and NB-IoT), cellular LTE, LPWA, industrial, automotive, aerospace, and military applications. The new Linx N connectors are available in a variety of styles, including surface mount, PCB mount, and cable-crimp mount. Linx is also offering N to N and SMA to N adapters, providing flexibility in design and integration through a range of solution options. The N connector series from Linx...

Thanks to TotalTemp Technologies for Continued Support!

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. Please contact TotalTemp Technologies today to learn how they can help your project.

Wednesday 9

For the Record: Popular Electronics Announcement

Radio Amateur News began life in July 1919, then changed its name a year later in July 1920 to Radio News. In August 1948 the title was again changed to Radio & Television News, then shortened to Radio & TV News in May 1959. Publication continued through April 1959. The next month's issue (May 1959) was entitled Electronics World, with Radio & TV News as a subtitle, and ran through December 1971, when it merged with Popular Electronics. Popular Electronics began publication as a new magazine in October 1954 and printed its final issue in October 1982. The next month it became Computer & Electronics, which continued until April 1985. From May 1985 through January 1989 it was called Hands-on Electronics. Believe it or not, in January 1990...

Aegis AC-DC Power Supply with Alignment to SOSA™ Technical Standard

"Aegis-Power-Systems-AC-DC-Power-Supply-SOSA-Standard-12-8-2020.htm" target="_top"> Aegis Power Systems announces the new VPX1PH3UC310-SA, a single-phase 85-264 Vac input to 28 Vdc output power supply module with 310 watts and EMI filtering. This rugged slide-in power supply has been developed in alignment with the Sensor Open Systems Architecture™ (SOSA) technical standard for use in interoperable systems for sensor management. Using the latest in switching power technology, this product achieves high efficiency AC-DC conversion with .99 power factor correction in a conduction cooled module with +12 V and +3.3V AUX outputs in alignment with the SOSATM technical standards. Users with increasing battlefield demands for C5ISR and embedded computing equipment can make use of advanced power converter features such as built-in EMI filtering, alignment keys for using multiple units in one chassis, I2C monitoring and IPMC redundancy, and wide operating temperature range...

Lower Current Leads to Highly Efficient Memory

"Researchers are a step closer to realizing a new kind of memory that works according to the principles of spintronics which is analogous to, but different from, electronics. Their unique GaAs-based ferromagnetic semiconductor can act as memory by quickly switching its magnetic state in the presence of an induced current at low power. Previously, such current-induced magnetization switching was unstable and drew a lot of power, but this new material both suppresses the instability and lowers the power consumption too. The field of quantum computing often gets covered in the technical press; however, another emerging field along similar lines tends to get overlooked, and that is spintronics..."

Broadcasting - As I Imagined It...

Dr. Lee DeForest might have had something like National Public Radio (est. 1970) in mind when he penned this article in 1933. In it, the famous vacuum tube amplifier inventor lamented and criticized the commercialization of broadcasts because of all the paid product announcements (aka commercials) that had been steadily increasing over the years. He also was critical of the "hit-or-miss, higgeldy-piggeldy mélange program basis" of programing; i.e., the same station playing a mix of jazz, opera, swing, syndicated story-telling, etc. The good doctor did not elaborate on where funding for such dedicated, uncorrupted broadcasts would originate if not from paying advertisers, and I do not recall ever reading about a DeForest Radio Network paid for by his vast fortune. I don't like commercials any more than the next person, but a company deserves time to pitch its products and/or services if it helps deliver...

2020 Ig Nobel Prizes Announced

The InCompliance website has a good synopsis of the 2020 Ig Nobel Prize winners. "And now for a bright spot in our chaotic world…. The 30th First Annual (not a typo!) Ig Nobel Prize ceremony was held virtually last month. Not to be confused with the Nobel Prizes being announced this week in Stockholm, Sweden, the Ig Nobel Prizes are intended to 'honor achievements that first make people laugh and then make them think.' This year's Ig Nobel Prize award winners include: For physics, a team of researchers from Australia, Ukraine, France, Italy, Germany, the United Kingdom and South Africa for determining experimentally what happens to the shape of a living earthworm when the earthworm is vibrated at a high frequency..."

Many Thanks to Qorvo / Custom MMIC for Their Continued Support

Qorvo / Custom MMIC is a fabless RF and microwave MMIC designer entrusted by government and defense industry OEMs. Custom and off-the-shelf products include switches, phase shifters, attenuators, mixers and multipliers, and low noise, low phase noise, and distributed amplifiers. From next-generation long range military radar systems, to advanced aerospace and space-qualified satellite communications, microwave signal chains are being pushed to new limits - and no one understands this more than Custom MMIC. Please contact Qorvo / Custom MMIC today to see how they use their modern engineering, testing and packaging facility to help your project. 

Tuesday 8

Electronics-Themed Comics, October 1947 Radio-Craft

Here are three more electronics-related comics to help brighten your day. They appeared in a 1947 issue of Radio-Craft magazine. The first one reflects what was a problem with early compact vacuum tube radios with molded plastic chassis. The gag is the lady's blaming the problem on something else unrelated. The term "table-top" probably originated in the early twentieth century to describe products which, prior to miniaturization efforts using newfangled materials and manufacturing methods, existed only in the form of large model that stood separately on the floor. The last comic could actually be applied to today's world...

Hollow Core Fibres Cut Communications Losses

"Optical fibres made of silica glass have been the transmission medium for a high-speed optical communications market estimated to be worth $40B globally. All-silicon optical transmitter operates at 100 Gbps The performance of optical fibres is negatively impacted by attenuation - the scattering of light inside the glass - that causes a loss in transmitted power. According to the University, this power loss limits the performance of applications requiring shorter wavelengths. In this new study, published in Nature Communications, researchers from Southampton University have demonstrated that guiding light through air-filled fibres offers a potential way to overcome..."

Axiom Blog: Equipment for an Electrical Engineer's Wish List

"Axiom-Test-Equipment-Electrical-Engineers-Wish-List-12-4-2020.htm" target="_top"> Axiom Test Equipment, an electronic test equipment rental and sales company has published a new blog post titled "Equipment for an Electrical Engineer's Wish List" that informs people who are looking to buy test equipment for an electrical engineer. Learn how you could give the gift of test equipment in a cost-effective manner and add to your favorite electrical engineer's test bench for 2021. No matter what is on their wish list, Axiom Test Equipment offers a variety of test equipment to meets their specific needs. Keeping costs reasonable is possible by either renting equipment for a short-term project or by purchasing quality used equipment at a fraction of the full price...

Pandemic Psychopathy

I saw this on a financial website:

Patient: "Doctor, doctor! When will this virus end?"

Doctor: "How would I know? I'm not a politician!" --- Sad but true.

Transistor Announcement in Boys' Life

The October 1952 issue of Boys' Life magazine story titled "Tiny But Tremendous Transistors," contained the first mention of transistors I can find in the Boy Scouts of America (BSA) flagship publication. Germanium was still the primary element used for semiconductors at the time, although silicon would soon replace it - and at a much lower cost. Whereas silicon is found on beaches all over the world (and everywhere else for that matter) in the form of sand, germanium at the time was obtained as a by-product of smelting zinc ore (which I didn't know until reading this story). Today, of course, both elements are abundantly available. Mr. Cavanaugh points out that although wonderful things are being done with transistors in the way of improving performance, lowering power requirements, and reducing product sizes and weights...

Antenna Physics: An Introduction 2nd Edition

Antenna Physics: An Introduction 2nd Edition, your complete guide to antenna theory, is thoroughly updated and includes new material to help you better understand the complexities of antenna theory. "World-recognized antenna technology expert Robert J. Zavrel, Jr., W7SX, is your guide to grasping a deeper understanding of how antenna systems function. In this book, he clearly communicates the theory and the mathematics that form the foundations upon which all antenna designs depend. Although competence with mathematics is necessary to get the most from this book, Antenna Physics: An Introduction offers knowledge that will help anyone create their own antenna designs..."

Please Visit Nova Microwave in Appreciation of Their Support

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. Available in single or multi-junction topographies, the Nova Microwave product line of is specifically designed for use in varied environmental and temperature extremes. 

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page. Some quoted items have been shortened to save space. About RF Cafe.

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