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Today in Science History

Tech Industry Headlines

Tech Industry Headlines - RF Cafe- Archive -

• The Global State of 5G Devices

European Microwave Week to Take Place as Scheduled in September

Radio Amateurs Team up to Help University Design Low-Cost Ventilator

• OneWeb Launches 34 More Internet Satellites

• U.S. Car Sales Could Slump 34% This Year

Education Must Keep Pace to Enable Technology Expansion

Acing the Phone Interview Is Easier Than You Think

• Errata to 2020–2024 Amateur Extra-Class Question Pool Released

Q1 Foundry Revenues up 30% YoY

Constant-Resistance Network Inductor Design

Constant-Resistance Network Inductor Design, April 1950 Radio & Televsion News - RF CafeIn this Radio & Television News magazine article, author Jack Gallagher derives a formula for the number of turns of wire to wind on a form of given dimensions for a parallel constant-resistance network. He argues that although commonly used formulas like that of Wheeler provide the number of turns needed to achieve a desired value of inductance, it does not predict the size of cross-sectional shape of a coil form that results in an optimal configuration. His work applies to audio frequency divider networks like those used for speakers to steer specific frequency ranges to a woofer, midrange, and tweeter trio; hence the need for "constant resistance" (e.g., for standard 8 Ω or 16 Ω speakers). By the way, in case you are not familiar with the annotation in older electronics articles, "mhy" is microhenries, and "s.c.c." is...

Notable Tech Quote: Concerning "Wavicles"

In Pursuit of the Unknown: 17 Equations That Changed the World - RF CafeIan Stewart, author - RF Cafe"Matter was neither particle nor wave, but a bit of both - a wavicle." - Ian Stewart, in "In Pursuit of the Unknown: 17 Equations That Changed the World," 2012, regarding the dual nature of light as covered in the chapter on Schrödinger's equation for wave functions. BTW, the real term used is "wave–particle duality," which is a quantum mechanical principle stating that all matter–energy has both a wave and a particle nature. The wave behavior of light is exhibited in its ability to be diffracted at a sharp edge. It is the particle nature which accounts for the photoelectric effect.

NEW - RF & Electronics Symbols for Visio

RF Electronics Wireless Analog Block Diagrams Symbols Shapes for Visio - RF CafeWith more than 1000 custom-built symbols, this has got to be the most comprehensive set of Visio Symbols available for RF, analog, and digital system and schematic drawings! Every object has been built to fit proportionally on the provided A-, B- and C-size drawing page templates (or can use your own). Symbols are provided for equipment racks and test equipment, system block diagrams, conceptual drawings, and schematics. Unlike previous versions, these are NOT Stencils, but instead are all contained on tabbed pages within a single Visio document. That puts everything in front of you in its full glory. Just copy and paste what you need on your drawing. The file format is XML so everything plays nicely with Visio 2013 and later...

Drone Radar Database Made Public for UAV Hunters

Drone Radar Database Made Public for UAV Hunters - RF Cafe"A database of drone radar cross sections has been made public to help those developing countermeasures. 'We measured drone radar cross sections at multiple 26-40 GHz mm−wave frequencies to better understand how drones can be detected, and to investigate the difference between drone models and materials in terms of scattering radio signals,' said researcher Vasilii Semkin of VTT Technical Research Centre of Finland. 'We believe that our results will be a starting point for a future uniform drone database. Therefore, all results are publicly available along with our research paper..."

11 Ways Engineers Are "Kung Flu Fighting"

11 Ways Engineers Are "Kung Flu Fighting" - RF CafeOk, the real title on the Interesting Engineering website is, "11 Ways Engineers Are Helping out to Fight Against the Pandemic." Individuals and companies (comprised of individuals) are responding to the COVID-19 crisis in an utterly amazing manner. Except for grandstanding politicians and agenda-driven, hateful media types, many of our fellow Earthlings are working tirelessly to provide a way out of this present surreal crisis, and in the process are developing new knowledge and technology that will benefit us during "the next big thing." Others do what they can do by honoring precautionary rules of sanitation and separation. Admittedly, the exercising of extreme governmental powers worries me a bit as limits of citizens' willingness to comply are tested. One American politician famously recommended, "You never let a serious crisis go to waste. And what I mean by that it's an opportunity to do things you think you could not do before." Here is the original 1974 "Everybody Was Kung Fu Fighting" song (I was in 10th grade). Be careful.

Prize Winners for Best "YL" Photos

Prize Winners for Best "YL" Photos, August 1935 Short Wave Craft - RF CafeIn an effort to promote entry of women and girls into the amateur radio hobby, Short Wave Craft magazine ran a few contests for Best "YL" Photos. Amazingly - and maybe there are still instances of it today - many (if not most) of the YLs featured had built their own equipment. In 1935, most people built their own equipment, so that is not too surprising. The winner for this month was a 16-year-old young lady (i.e., "YL") who in fact built her rig. Another winner was an 83-year-old grandma who was born before Marconi, Maxwell, and Hertz did their best work! The third winner was a girl who earned her Ham license at age 6, which back in the day required sending and receiving 5 words per minute (WPM) in Morse code. BTW, according to the Bureau of Labor Statistics' (BLS) Inflation Calculator says $5 in 1935 is the equivalent of $94.41 in 2020 money...

Anatech Electronics: Off-the-Shelf and Custom RF & Microwave Filters

Anatech Electronics logo - RF CafeAnatech Electronics (AEI) manufactures and supplies RF and microwave filters for military and commercial communication systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard RF filter and cable assembly products are published in our website database for ease of procurement. Custom RF filters designs are used when a standard cannot be found, or the requirements dictate a custom approach for your military and commercial communications needs. Sam Benzacar's monthly newsletters address contemporary wireless subjects. Please visit Anatech today to see how they can help your project succeed. 

U.H.F. Fringe Antenna Installations

U.H.F. Fringe Antenna Installations, April 1954 Radio & Televsion News - RF CafeMultiple path transmission, diffraction around obstacles, absorption by foliage, and reflection from moving objects have always been challenges to the wireless system designer and/or user. Whether it concerns communications between a WiFi router and a notebook computer, a cellphone and a tower, an FM radio with a broadcast station, or deep space probe with an earth station, all of the aforementioned mechanisms must be dealt with to some degree. Although in a different way, even transmissions within a waveguide or coaxial cable deal with those same issues - reflections and the resulting standing waves have the same effect as multipath in terms of vectorially additive versions of the same original signal. Signal degradation issues can usually be overcome when all components are performing within specifications, by having knowledge of potential causes, and then assessing the situation at hand. Of course an insufficient signal power from the transmitter, too-high Friis-determined atmospheric path loss...

ConductRF Performance Flexible RF Cables to 18 GHz

ConductRF Performance Flexible RF Cables to 18 GHz - RF CafeConductRF LSA series of Low Loss, Performance flexible RF cable assemblies, provide microwave system designers with a versatile solution for most applications. Here we offer customers a solution for 0.086" diameter cable that facilitates greater flexibility and handling or, 0.141" diameter that exploits the same great performance but with almost half the loss. Connector options include SMA, Type-N, TNC & SMP that provide excellent VSWR between DC and 18 GHz, also solutions for MCX & SMB are available in a wide array of configurations. These assemblies are built using our own double shielded, FEP jacketed cable, that was developed specifically for performance solutions. With shielding effectiveness exceeding 90 dB through 18 GHz, these cables minimize the threat of cross-talk effect. ConductRF guarantees its performance through 100% factory test prior to shipping. Additional options are also available...

Methods to Increase Channel Capacity in RF Data Links

Methods to Increase Channel Capacity in RF Data Links - RF CafeTriad RF Systems' Steve Barthelmes, Patrick Sherlock, and Ken Andrew  published a Technical Brief article entitled, "Methods to Increase Channel Capacity in RF Data Links," in Microwave Product Digest. "As can be seen, increasing the robustness of RF links is a tricky business, however, there are multiple weapons in one's toolkit to increase capacity and combat RFI. MIMO is a radio technology that is taking hold worldwide. This wireless technology increases the channel capacity of the system while improving the reliability of the link. High gain antennas and tracking technologies can be employed, however, the mobile aspects of many RF links (UxV systems) do not always allow for the size, complexity, and sensitivity trade-offs that come along with them. BDAs can be employed, in conjunction with these other technologies, or alone, to increase the link margin of systems that are underperforming..."

How Did Dilbert Get His Name?

How Did Dilbert Get His Name? (Dilbert the Pilot) - RF CafeDo you know how engineering whipping boy Dilbert came to be called by that name? Per Scott Adams, while working at Pacific Bell he ran an informal name-the-comic-strip-engineer contest from his cubicle. A guy named Mike Goodwin suggested Dilbert. "I ended the contest immediately and declared Mike the winner," says Adams. It sounded perfect. Years after the comic strip had become syndicated, Mike commented that he believes the name idea might have come from seeing his father's old WWII aviator comics with "Dilbert the Pilot." DtP was a screw-up, invented by Navy artist Robert Osborn, whose purpose in life was to illustrate the wrong way of doing things so that real pilots wouldn't make the same mistakes. The name was funny then, as it is funny now. BTW, Dilbert is a variant of Delbert meaning nobly famous. During the War, "dilbert" became a synonym for "blunder" for Navy pilots. The Navy even produced an aviator safety film titled, "Don't Kill Your Friends," featuring Dilbert the Pilot...

Verizon Demos Peak Speeds of 4.2 Gbps on Live 5G Network

Verizon Demos Peak Speeds of 4.2 Gbps on Live 5G Network - RF Cafe"Verizon, along with Samsung Electronics Americas, Motorola Mobility, and Qualcomm Technologies, have teamed up to demonstrate 5G peak speeds of 4.2 Gbps on a live 5G network. Using carrier aggregation, a technology that combines multiple channels of spectrum to provide greater efficiency for data sessions transmitting over the wireless network, the four companies combined eight separate channels of mmWave spectrum to achieve the multi-gigabit speeds on Motorola's upcoming flagship smartphone. Adam Koeppe, Senior Vice President of Technology Planning at Verizon commented that they are continuing to expand the 5G Ultra Wideband network, built to enable unique and transformational experiences for their customers. They continue to innovate and introduce advanced technologies on their 5G network that will help them reach 'never seen before' mobile capabilities..."

Res-Net Microwave: Precision RF & Microwave Components

Res-Net Microwave Components - RF CafeRes-Net Microwave has a complete line of precision RF & microwave components including attenuators, terminations, resistors, and diode detectors for commercial, military, and space applications. Products range from the small flange type to large 2,000 watt connectorized power attenuators and/or terminations at frequencies up to 26.5 GHz. In-house photo etch and laser trim capability. The company is a leader in development and production of the films required for these type of RF/microwave components. Please check out Res-Net Microwave's website to see how they can help with your current project.

Mac's Service Shop: Zenith's 1973 Color Line

Mac's Service Shop: Zenith's 1973 Color Line, March 1973 Popular Electronics - RF CafeThose of us who have been around for six or more decades have lived through two evolutions of video display types - raster scanned cathode ray tubes (CRTs) and digitally pixelated light-emitting diode (LED) and liquid crystal (LCD) displays. Unlike with the latter display types that improved in color depth, picture resolution and display size, the former had effectively a fixed resolution of horizontal lines (525 vertical steps - only 484 visible, actually, due to blanking). That meant for CRTs, designers needed to find ways to make images appear in-focus while also looking continuous on larger screens. Doing so involved cleverly adjusting the size and spacing of fluorescent color dots on the picture tube face while also using special metal masks between the electron gun and the tube. A lot of research that included panels of people rendering opinions...

You Know You're an Engineer If…

You Watched These Movies and TV Shows as a Kid - RF Cafe...You Watched These Movies and TV Shows as a Kid. The Design News website likes to run these "You Know You're an Engineer If..." things, and usually they're pretty good. This one, of course, has me waxing nostalgic. "Here are some of classic engineering and robot movies and TV shows from the 1950s and 1960s. Every kid who grew up to be an engineer loved robots. The love of science fiction and robots seems to follow closely on the heels of the fascination with dinosaurs. Some of these movies were scary for a kid, like the deadly robot in The Day the Earth Stood Still. Others were lovable, like Robbie the Robot in Forbidden Planet. Some were terrifying in a more realistic way, such as HAL in 2001 a Space Odyssey..."

FQXi: Is Reality Digital or Analog?

FQXi: Is Reality Digital or Analog? - RF CafeEach year the Foundational Questions Institute (FQXi) holds an essay contest inviting writers to submit missives addressing the question chosen by the FQXi board as being particularly thought-provoking. In their words, "FQXi catalyzes, supports, and disseminates research on questions at the foundations of physics and cosmology, particularly new frontiers and innovative ideas integral to a deep understanding of reality, but unlikely to be supported by conventional funding sources." The 2011 question was "Is Reality Digital or Analog?" Scientific American magazine, being one of three partners, published the runner-up entry in the December 2012 issue: University of Cambridge professor of theoretical physics professor David Tong's paper argues that the world is in fact fundamentally analog. Professor Tong actually tied for second place, but for some reason SciAm does not tell us whether the other second place paper supported an analog or digital viewpoint...

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...

Cubic Receives $5.1B Tactical Communication Contract from the U.S. Army

Cubic Receives $5.1B Tactical Communication Contract from the U.S. Army - RF Cafe"Provider of integrated solutions for transportation and defense C4ISR, Cubic Corporation has announced that their Cubic Mission Solutions (CMS) business division has been selected as one of the awardees to compete under the U.S. Army for Global Tactical Advanced Communication Systems (GTACS II) Indefinite Delivery/Indefinite Quantity (IDIQ) contract vehicle. The contract has a ceiling of $5.1 billion, with a five-year base, one five-year option period and a Firm Fixed Price, Cost Plus Fixed Fee and Cost No Fee contract, in support of the Program Executive Office Command, Control and Communications-Tactical (PEO C3T), and Project Manager Tactical Network (PM Tactical Network)..."

New Stunts with Short Waves

New Stunts with Short Waves, April 1935 Short Wave Craft - RF CafeAs with many relatively new technologies, the exuberance over radio peaked quickly once the benefits of communications over long distances without the need for wires was realized by the public. After a couple decades a lot of "authorities" began pontificating about how all the useful applications of radio waves had been discovered and that any new innovation would be merely incremental improvements in existing technology. Novel circuits for minimizing static over the radio or maybe building more powerful transmitters for longer range were the only concepts within reach of their limited imaginations. Similar phenomena occurred for those who thought airplanes would always have two (or more) wings and that automobiles would never be faster than a train. This 1935 issue of Short Wave Craft magazine reported on the beginnings of investigations into the use of radio waves for heating...

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    Kirt Blattenberger,

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 Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

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