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Homepage Archive - March 2020 (page 2)

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. About RF Cafe.

Homepage Archive Pages

2020:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2019:
  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2018:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2017:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2016:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2015:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2014:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2013:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2012:  1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13


See Page 1 | 2 | 3 | 4 | 5 | of the March 2020 homepage archives.
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Friday 13

FM Broadcasting in Western Germany

FM Broadcasting in Western Germany, March 1953 Radio-Electronics - RF CafeWhile FM broadcasting (frequency modulation) began in the United States in the late 1930s, it was not until after World War II and even the Korean War, in the 1950s, that the major shift to FM took place. It took even longer for FM to get a foothold in Europe mainly due to the emphasis on rebuilding essential infrastructure and manufacturing destroyed by the war. As this article points out, the newer FM radio features allowed it to thwart some of the propaganda efforts of the Soviets in East Germany who would be stuck in technologies that lag two or more decades behind the free world even to this day (ain't Communism / Socialism great?). The "medium-wave band" referenced herein is AM (amplitude modulation), so replacing dominant radio broadcasting with FM systems would effectively cut off AM propaganda. FM radios were being produced so inexpensively in the U.S. that they were very affordable in Europe was well. There is no mention of whether the West German government subsidized the purchase of FM receivers by citizens...

Out of Order: Attack of the Cookie Monster

Out of Order: Attack of the Cookie Monster - RF CafeDuring my electronics technician days at the Westinghouse Electric Company's Oceanic Division in Annapolis, Maryland, I spent the first couple years building printed circuit boards, wiring harnesses, and system-level assemblies for U.S. Navy sonar systems. We had some really slick stuff like towed vehicles with transducer arrays along the sides, nose cones for smart torpedoes, flow sensors, proximity fuse elements, etc. Exposure to all that, and the super-smart people that designed it, fuelled my desire to go to the trouble of earning an engineering degree. One of my tasks for a while was to build the transducer arrays, which entailed building the hundreds of tiny transducer elements. One of the phased array acoustic antennas was mounted on each side of the AN/AQS-14 towed sonar vehicle...

Please Visit Triad RF Systems to Thank Them for Their Support

Triad RF SystemsTriad 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.

Post Your Engineer & Technician Job Openings on RF Cafe for Free

Engineering Job Board - RF CafeRF Cafe's raison d'être is and always has been to provide useful, quality content for engineers, technicians, engineering managers, students, and hobbyists. Part of that mission is offering to post applicable job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge (of course a gratuity will be graciously accepted). 3rd party recruiters and temp agencies are not included so as to assure a high quality of listings. Please read through the easy procedure to benefit from RF Cafe's high quality visitors...

3D Inductor Technology Expands Microchip Capability

3D Inductor Technology Expands Microchip Capability - RF Cafe"Using 3D components on a standardized 2D microchip manufacturing platform uses up to 100 times less chip space. A scanning electron microscope micrograph of a rolled microinductor architecture, approximately 80 micrometers in diameter and viewed from one end looking inward. Engineers have boosted the performance of 3D inductor technology by adding as much as three orders of magnitude more induction to meet the performance demands of modern electronic devices. The microchip inductor is capable of tens of millitesla-level magnetic induction. Using fully integrated, self-rolling, magnetic, nanoparticle-filled tubes, the technology ensures a condensed magnetic field distribution and energy storage in 3D space - all while keeping the tiny footprint needed to fit on a chip..."

everythingRF: Their Name Says It All

everything RF Searchable Database - RF CafePlease 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.

How Things Work: Cabin Pressure

How Things Work: Cabin Pressure - Airplanes and RocketsThis article from the January 2020 issue of Air & Space magazine explains why you remain conscious at 30,000 feet. "We humans need air to breathe, so we do best around sea level. Airplanes are at their best up high, where the air is thin and smooth. And therein lies the rub: We invented a machine that thrives where we don't. This became obvious as soon as engine power increased to a point at which aviators could reach altitudes where they lost consciousness. At first, fliers coped by filling tanks with pressurized oxygen and inhaling the gas through rubber tubes; later, form-fitting face masks made oxygen delivery more reliable. In many high-flying light airplanes and military aircraft, oxygen systems and face masks..."

Thursday 12

B&K Dyna-Quik Tube & Transistor Tester

B&K Dyna-Quik Tube & Transistor Tester, February 1958 Radio & TV News - RF CafeWay back in the 1980s while working at Westinghouse Oceanic Davison in Annapolis, Maryland, an engineer who knew I had recently obtained a 1941 Crosley Model 03CB console style radio generously gave me his B&K Dyna−Quik Model 650 Vacuum Tube Tester. It is a very comprehensive portable tester used by many professional radio and television servicemen. My tester also had the Model 510 Accessory Socket Panel that added an ability to test 50% more tube types. One indication that it is one of the later model tube testers is the inclusion of a transistor testing socket. Unlike testing vacuum tubes, all of which plugged into sockets to make them easily replaceable, testing a transistor or solid state diode required unsoldering or clipping the device out of the circuit and then soldering back in either the verified still good device or a replacement. It was one of the reasons electronics servicing people eschewed the adoption of semiconductors...

NASA Aerospace Communication Facility to Focus on RF Research

NASA Aerospace Communication Facility to Focus on RF Research - RF Cafe"NASA hosted a groundbreaking ceremony for its upcoming new Aerospace Communications Facility (ACF) at the agency's Glenn Research Center in Cleveland on Wednesday, March 4. The Glenn Research Center continues to develop advanced radio frequency (RF) technology for NASA's aeronautics, science, and human exploration missions. The new facility will enable Glenn to further advance communication technology needed to meet the nation's space exploration and aviation goals, as well as enable commercial and defense communications. The upcoming 54,000 square foot facility will be NASA's premier facility for RF communications technology research and development. It will allow NASA and commercial partners to develop faster, higher capacity communications for future missions to the Moon and Mars..."

A Winding Machine for Spaced-Turn Chokes

Experimenter's Section: A Winding Machine for Spaced-Turn Chokes, December 1931 QST - RF CafeThere are still a lot of people who wind their own coils, whether it be for an amateur radio rig or for work in the lab. I know I've wound many a coil around a drill bit or wooden dowel. This simple coil winding machine that appeared in a 1931 edition of QST magazine would be a handy addition to anyone's bag of tricks, especially if find yourself winding single-layer coils that have a fixed space between the windings. The home stores like Lowes and Home Depot sell small pieces of oak that would be perfect for this kind of project. A little stain and a coat of varnish would give it a real vintage look. Use your soldering iron to burn your name onto the base...

Many Thanks to ConductRF for Continued Support!

ConductRF coaxial cables & connectors - RF CafeConductRF is continually innovating and developing new and improved solutions for RF Interconnect needs. See the latest TESTeCON RF Test Cables for labs. ConductRF makes production and test coax cable assemblies for amplitude and phased matched VNA applications as well as standard & precision RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the iBwave component library. They also provide custom coax solutions for applications where some standard just won't do. A partnership with Newark assures fast, reliable access. Please visit ConductRF today to see how they can help your project! 

RF Low Noise Amplifier Technology Landscape

RF Low Noise Amplifier Technology Landscape - RF CafeHere is an interesting article from the February 2020 issue of High Frequency Electronics magazine entitled, "RF Low Noise Amplifier Technology Landscape Grows More Diverse," by Tim Galla. The huge number of semiconductor types now available - SiGe, SiGe BiCMOS, SiGe:C, GaAs, AlGaAs/GaAs, GaN, AlGaN/GaN, InP, AlInP/InP, SoI, Bi-CMOS, CNT - is largely responsible for the improvements in LNA performance. I remember when finding a packaged LNA with 50 Ω ports and a noise figure of less than 1.0 dB was hard to do. Now, they are commonplace - and at good prices. It begins: "RF low noise amplifiers (LNAs) fabricated with solid state technology have been in use for several decades. The early transition to solid state was pioneered with germanium, has subsequently transitioned to silicon, and has now expanded to include a wide range of compound III-V semiconductors and new carbon-based materials. The rapid adoption and advancement of LNA technologies is largely do the growth and diversification of RF applications, and the specific requirements for these new and varying use cases. These requirements include the recent focus of greater linearity..."

Cox Control Line Demonstration Circle

Disneyland Rocket to the Moon cox Control Line Demonstration Circle - Airplanes and RocketsFrom 1955 to 1961, the TWA-sponsored "Rocket to the Moon" was the E-ticket attraction of Tomorrowland, the neighborhood of the Disneyland theme park modeled after a speculative utopian future. Eric Boehm, in the "Letters" section of the January 2020 issue of Air& Space magazine, submitted the following comment: "'My Trips to the Moon' (Sept. 2019) and the accommodating photos really caught my eye, and not because of the big TWA rocket. the fenced-off area in the foreground was the Disney Flying Circle. Between 1955 and 1966, daily demonstrations were conducted using control-line model airplanes and gas-powered tether cars. The photo shows a man in the center with both hands raised. He may be flying two models at once, which was a regular display feature. There was one employee named Bart Klapinski who could fly three airplanes simultaneously: One control handle in each hand and a third in his mouth.

QuinStar Technology: mm-Wave Active & Passive Components

QuinStar Technology mm-Wave Products - RF CafeQuinStar Technology designs and manufactures mm-wave products for communication, scientific, and test applications along with providing microelectronic assembly, rapid prototyping, and mass customization. Amplifiers, Oscillators, Switches, Attenuators, Circulators, Isolators, Filters, Waveguide, Antennas, Phase Shifters, Transceivers, Mixers, Detectors. QuinStar specializes in cryogenic amplifiers, circulators, and isolators. Please visit QuinStar today to see how they can help your project. 

Wednesday 11

De Forest the Inventor

De Forest the Inventor, January 1947 Radio-Craft - RF CafeWhen most people are asked to name prolific inventors, people like Thomas Edison and George Westinghouse, with 1084 and 361 each, respectively, come to mind - at least for the United States. As of this writing, Kangguo Cheng of IBM holds the record with 2039 U.S. patents assigned. Nikola Tesla had about 300 patents. Lee de Forest, the subject of this 1937 Radio−Craft article, had a little over 180 patents. That still qualifies as prolific by my estimation. However, there is more to ranking a person's inventive worth than the number of patents awarded - like how profoundly his or her invention(s) impacted the world. For instance, Alexander Graham Bell had a mere 18 patents awarded in only his name, with 12 more shared patents. If you look through Wikipedia's "List of Prolific Inventors," you will see a lot of names with a lot of patents assigned, but most of those names are probably unfamiliar. Have you noticed how many of the old patent art looks like..." 

Small Step for Atoms, Giant Leap for Microelectronics

Small Step for Atoms, Giant Leap for Microelectronics - RF Cafe"Step by step, scientists are figuring out new ways to extend Moore's Law. The latest reveals a path toward integrated circuits with two-dimensional transistors. A Rice University scientist and his collaborators in Taiwan and China reported in Nature today that they have successfully grown atom-thick sheets of hexagonal boron nitride (hBN) as two-inch diameter crystals across a wafer. Surprisingly, they achieved the long-sought goal of making perfectly ordered crystals of hBN, a wide band gap semiconductor, by taking advantage of disorder among the meandering steps on a copper substrate. The random steps keep the hBN in line. Set into chips as a dielectric between layers of nanoscale transistors, wafer-scale hBN would excel in damping electron scattering and trapping that limit the efficiency of an integrated circuit. But until now, nobody has been able to make perfectly ordered hBN crystals that are large enough..."

Anatech Electronics March 2020 Product Update

Anatech Electronics March 2020 Product Update - RF CafeAnatech Electronics is a privately-held company founded in 2003 that focuses on supplying quality RF and microwave products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. In their March Product Update, Anatech has introduced two connectorized and a surface mount duplexer: an n8 / Extended GSM Band cavity type duplexer with 70 dB isolation, an n30 / WCS Band cavity type duplexer with 70 dB isolation, and an n2 / PCS Band surface mount ceramic duplexer with only 3.7 dB insertion loss. Custom RF power directional coupler designs can be designed and produced when a standard cannot be found, or the requirements are such that a custom approach is necessary...

That Word You Heard: Vinculum

That Word You Heard: Vinculum - RF CafeHow would you handle evaluating this formula: a + b * c + d ?  The March/April issue of Discover magazine ran a short article on the history of the vinculum - that horizontal line which goes between the numerator and denominator of a fraction (e.g., ¾), and over a number to indicate that it repeats (e.g., 1/3 = 0.3). Prior to a century or two ago, it had other common applications as well. The thumbnail above, which shows many of the vinculum's uses, cuts off the most important part of the full image that appears in the magazine. The answer to the question is thus: (a + b) * c + d . Begins the article: "What's a mathematician's favorite bar? A vinculum, of course. This simple-yet-versatile line holds numbers apart in fractions, sits atop decimal places when they repeat forever and shows which terms are about to be square-rooted. Centuries ago, vincula also did the work that parentheses do today, denoting which terms in an equation should be solved first. But this use fell out of favor as the printing press gained popularity, since parentheses were much easier for typesetters..."

Many Thanks to MECA Electronics for Their Long-Time Support!

MECA ElectronicsSince 1961, MECA Electronics has designed and manufactured an extensive line of RF & microwave components for in-building, satellite, radar, radio, telemetry, mobile radio, aviation & ATC. Attenuators, directional & hybrid couplers, isolators & circulators, power dividers & combiners, loads, DC blocks, bias-Ts and adapters & cables. MECA has long been the 'backbone' of high performance wired and air-interfaced networks such as in-building applications, satellite communications, radar, radio communications, telemetry applications, mobile radio, aviation & air traffic communications. 

Impact of Coronavirus on Distributors of Electronic Components

Impact of Coronavirus on Distributors of Electronic Components - RF Cafe"Here's a quick snapshot of where things currently stand across the industry. Over the last months, there has been a great amount of global media coverage on the new coronavirus (COVID-19). The range of data differs from facts and figures to unrefined conspiracy theories. So before jumping into an investigation of the effect of coronavirus on distributors of electronic parts, we'll give a short update. Impact on the Electronics Industry - The electronics industry isn't making an exemption here. In the most recent weeks almost every maker has given out explanations on how the coronavirus and initiated quarantine in China is influencing their lead times. Moreover, numerous organizations have declined to participate in significant exchange fairs - for example, Embedded World. Coordinators of the Mobile World Congress in Barcelona even cancelled the event."

KR Electronics: RF & Microwave Filters

KR ElectronicsKR Electronics designs and manufactures high quality filters for both the commercial and military markets. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop and individually synthesized filters for special applications - both commercial and military. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. All common connector types and package form factors are available. Please visit their website today to see how they might be of assistance. Products are designed and manufactured in the USA.

Tuesday 10

1st Tubeless Light Amplifier

1st Tubeless Light Amplifier, March 1955 Radio & Televsion News - RF CafeWhat got my attention in this 1955 Radio & Television News magazine article was the "picture-on-the-wall" concept being predicted by General Electric (G-E) engineers, based on its light-amplifying phosphor invention. Determining exactly how the device works is difficult based on the information given, but it appears that the ultraviolet light source which is being amplified is projected onto the surface of the amplifying substrate, and then an exact duplicate of the image is reemitted toward the viewer. The conceptual drawing of a large screen hanging on the wall is most likely driven by a UV projector located near the ceiling, akin to how the large screen home theaters popular in the early 2000s worked (though with no amplification by the screen). Obviously the scheme never came to commercial fruition since such systems were never widely used. Other anticipated applications included  x-ray fluoroscopy, photography, "seeing-in-the-dark" (aka infrared night vision) devices...

Integrating Electronics onto Physical Prototypes

Integrating Electronics onto Physical Prototypes - RF Cafe"MIT researchers have invented a way to integrate 'breadboards' - flat platforms widely used for electronics prototyping - directly onto physical products. The aim is to provide a faster, easier way to test circuit functions and user interactions with products such as smart devices and flexible electronics. Breadboards are rectangular boards with arrays of pinholes drilled into the surface. Many of the holes have metal connections and contact points between them. Engineers can plug components of electronic systems - from basic circuits to full computer processors - into the pinholes where they want them to connect. Then, they can rapidly test, rearrange, and retest the components as needed..."

Reusable Coffee Cup in the Age of Coronavirus - Really Bad Idea

Reusable Coffee Cup in the Age of Coronavirus Is a Really Bad Idea - RF CafeThis being about coffee, it is engineering-related and thus qualifies as a relevant news item. "Just when the 'greens' thought they'd won over the giant coffee industry and Starbucks, in particular, with its reusable coffee cup campaign, to rid the world of single-use plastics, along came the coronavirus. According to articles on several news sites, Starbucks has banned customers from bringing their reusable cups into the stores for refills because of the pandemic. ...It's for that reason that health department regulations have typically prohibited people from bringing their own cups and glasses to dining establishments. It's why buffets require people to get a clean plate each time they go back for seconds and thirds..."

An Amateur Application of Modern Filter Design

An Amateur Application of Modern Filter Design, July 1966 QST - RF CafeThe term "modern" in the title of any book or article never has set right with me because it is utterly ambiguous about the era to which "modern" refers. Sure, it sounds good at the time, but when applied to this 1966 QST article, "modern" should be replaced with "four-decade-old." However, in this case the content is still relevant even thought it was written so long ago (or else I would not be reproducing it here). It may well have been most people's first exposure to elliptical (Cauer) filters. As you might expect, the rigorous, headache-inducing mathematics is omitted, but the article does give an example of implementing an audio frequency bandpass filter by cascading a lowpass filter and a highpass filter. If you are familiar with filter design, you know that because of phasing and inband impedance mismatch issues you cannot simply butt the two together to yield an equivalent bandpass filter. In fact, the author found it necessary to insert a 13 dB attenuator between them in order to get acceptable performance...

Please Visit Triad RF Systems to Thank Them for Their Support

Triad RF SystemsTriad 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.

5G Radiating Cables for In-Tunnel Deployments

5G Radiating Cables for In-Tunnel Deployments - RF CafeLeaky coaxial cables are not always a bad thing. "Radio Frequency Systems (RFS) has released new radiating cables for delivering 5G connectivity in tunnels. The latest patented Radiaflex cable supports all mission critical and commercial wireless services, working in all 3GPP bands up to 3.8 GHz. Using RFS's unique mode suppression technology the ultra-broadband cable works with no stop-bands to support current and future frequency needs, protecting customer investment from spectrum re-banding and preempting new generation requirements for years to come. The cable is technology agnostic, giving complete flexibility to customers, supporting mixed configurations and multi-operator or shared infrastructure deployments..."

Innovative Power Products: RF & Microwave Passive Components

Innovative Power ProductsInnovative Power Products (IPP) has over 30 years of experience designing & manufacturing RF & microwave passive components. Their high power, broadband couplers, combiners, resistors, baluns, terminations and attenuators are fabricated using the latest materials and design tools available, resulting in unrivaled product performance. Applications in military, medical, industrial and commercial markets. Take a couple minutes to visit their website and see how IPP can help you today.

Monday 9

Video Games Downloaded over the Radio in the 1980s

You Could Download Video Games from the Radio in the 1980s - RF CafeI was around and doing computers in the 1980s, but do not remember this. The aptly named Interesting Engineering website has this piece on how back in the early days of personal computing, some radio stations would broadcast over the air digital code for video games. That was when 16-color, 640x480-pixel CGA CRT displays were considered bleeding edge. A video contains the complete audio transmission, which will remind you of the times of trying to sign onto AOL or Compuserve with your 1200 baud telephone modem when a connection took 5 minutes to complete because of too many users and too few open lines. The little dude in the "Manic Miner" looks like one of the Mario Brothers...

Free Engineering Magazines & Whitepapers

Engineering White Papers & Books, March 2020 - RF CafeLots 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...

Pasternack Expands Millimeter-Wave Waveguide Antenna Product Line

Pasternack Expands Millimeter-Wave Waveguide Antenna Product Line - RF CafePasternack, an Infinite Electronics brand and a leading provider of RF, microwave and millimeter wave products, has expanded its offering of mmWave waveguide antennas to address the growing number of 5G and other high-frequency applications. Pasternack's line of millimeter-wave, waveguide antennas has added 54 new models and now covers broad operating frequency ranges from 1.7 to 220 GHz, provides nominal gain ranging from 0 dBi to 40 dBi, and features a variety of different waveguide sizes. Five new categories of high frequency waveguide antennas are now available to address point-to-point and point-to-multi-point wireless applications, including probe waveguide antennas to 170 GHz with 6.5 dBi of gain...

Many Thanks to Axiom Test Equipment for Continued Support!

Axiom Test Equipment - RF CafeAxiom Test Equipment allows you to rent or buy test equipment, repair test equipment, or sell or trade test equipment. They are committed to providing superior customer service and high quality electronic test equipment. Axiom offers customers several practical, efficient, and cost effective solutions for their projects' TE needs and is committed to providing superior customer service and high quality electronic test equipment. For anyone seeking a way to offload surplus or obsolete equipment, they offer a trade-in program or they will buy the equipment from you. Some vintage items are available fully calibrated. Please check out Axiom Test Equipment today!

Coronavirus COVID−19 Global Cases by Johns Hopkins

Coronavirus COVID-19 Global Cases by Johns Hopkins - RF CafeHere is a useful interactive map of worldwide reported coronaviruses (COVID−19), compliments of Johns Hopkins. As of this screen capture there have been reported (important distinction) 111,228 cases with 3,892 deaths (3.50%) and 62,369 people who have recovered (56.1%), leaving 40.4% undetermined. While I do believe the media and governments are over-hyping this by feeding and exploiting fear, it is useful to see how effectively the people of the world can work together in an emergency when motivated. As usual, the knowledgeable folks get the job done while politicians and TV stars expose their collective ignorance and egos. Maybe there are politivirus and mediavirus strains mutating out there somewhere to spare the world some misery.

Bittele Electronics: PCB Fabrication & Assembly

Bittele Electronics PCB Fabrication - RF CafeSince 2003, Bittele Electronics has consistently provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly services. It specializes in board level turnkey PCB assembly for design engineers needing low volume or prototype multi-layer printed circuit boards. Free Passive Components: Bittele Electronics is taking one further step in its commitment of offering the best service to clients of its PCB assembly business. Bittele is now offering common passive components to its clients FREE of Charge.

Sunday 8

Engineering & Science Crossword Puzzle for March 8

Engineering & Science Crossword Puzzle March 8, 2020 - RF CafeAs with my hundreds of previous science and engineering-themed crossword puzzles, this one for March 8, 2020, contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc., which I have built up over nearly two decades. Many new words and company names have been added that had not even been created when I started in the year 2002. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure village in the Andes mountains. You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which, if you don't already know, might surprise you.

   
About RF Cafe
Kirt Blattenberger - RF Cafe Webmaster
Copyright: 1996 - 2024
Webmaster:
    Kirt Blattenberger,
    BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while typing up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

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