Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations Engineering Event Calendar RF Engineering Quizzes USAF radar shop Notable Quotes App Notes Calculators Education Engineering Magazines Engineering magazine articles Engineering software Engineering smorgasbord RF Cafe Archives RF Cascade Workbook 2018 RF Stencils for Visio RF & EE Shapes for Word Advertising RF Cafe Homepage Sudoku puzzles Thank you for visiting RF Cafe!
Innovative Power Products Couplers

- Welcome to the RF Cafe Website -

"X-rays will prove to be a hoax." -- Lord Kelvin (Sir William Thomson)

Today in Science History

Tech Industry Headlines

Tech Industry Headlines - RF Cafe- Archive -

• Cooperative Agrees to Pay FCC Fine for Violating Antenna Inspection Rules

• U.S. Semiconductor Industry Veterans Keep Wary Eyes on China

• Nanomaterials Scientists Pave Way for Ultra-Tiny Electronics

Does U.S. Need Its Own Nokia, Ericsson, Huawei?

Multi-Mode Radar for sUAV Able to Track Moving Targets on Ground

Who Really Did Invent the Transistor?

• Here's Why You Can't Have 5G Right Away

iPhone 11 and 11 Pro Max Teardowns

• Sound Exchange CEO Consistently Criticizes "Big FM Radio"

Spot Radio News

Spot Radio News, November 1944 Radio News - RF CafeAccording to an item in this late 1944 issue of Radio News magazine, the six-hour delay which occurred between the time the armistice was signed at the end of World War I and the time news reached the battlefields, many men, women, and children on all sides died needlessly. Almost as many were maimed or injured. That might seem like a stretch, but in the 4 years, 3 months, and 2 weeks of the "the war to end all wars," an estimated 14 to 19 million lives were lost. It is an average of 375 to 500 casualties per hour, or 2,200 to 3,000 in six hours. Planners expected that the widespread availability of wireless communications (radio) meant that when the end World War II was finally announced, a cease fire on all fronts would be effected in less than half an hour ...

Characterizing Uncertainty in S-Parameter Measurements

Characterizing Uncertainty in S-Parameter Measurements - RF CafeA team of authors from the Federal Institute of Metrology (METAS), Berne-Wabern, Switzerland, have published an article in Microwave Journal entitled, "Characterizing Uncertainty in S−Parameter Measurements," which poses - and answers - the question, "If it is that easy to take two measurements and obtain different results, how can one know which measurement is correct?" "Every measurement, no matter how carefully performed, inherently involves errors. These arise from imperfections in the instruments, in the measurement process, or both. The 'true value of a measured quantity' (atrue) can never be known and exists only as a theoretical concept. The value that is measured is referred to as 'indication' or (aind) ..."

Intro to SAW Filter Theory & Design Techniques

Intro to SAW Filter Theory & Design Techniques - RF CafeUnlike other websites, I never require you to provide personal information in order to access someone else's (or my own) app notes / whitepapers. The app note entitled "Introduction to SAW Filter Theory & Design Techniques," by API Technologies, can be downloaded directly from the company website without registration. It begins, "In theory, an ideal filter would possess no loss, an instantaneous transition from the pass band to the stop band, infinite stop band attenuation, no signal distortion introduced by the filter and have very small size and cost. In reality, many tradeoffs need to be considered when selecting a filter for a system design. An advantage of SAW filter technology ..."

Thanks to VidaRF for Many Years of Supporting RF Cafe!

vidaRF passive RF & microwave components - RF CafeAt VidaRF, the phrase 'Providing Simple Solutions for Complex Connections' is more than just a slogan – it's a mindset, a mission, and a driving force behind everything we do. Their pledge is to design and distribute high performance, cost effective RF Microwave products to fit each customer's unique applications. Please visit VidaRF today to see how their lines of Attenuators & Terminations, Directional Couplers, Power Dividers, Coaxial Connectors, and Circulator & Isolators can be of use to your project. "When the standard just will not do, VidaRF has the solution for you!"

RCA Test & Measurement Equipment Advertisement

RCA Test & Measurement Equipment Advertisement, December 1947 Radio News - RF CafeJust as the test and measurement equipment manufactures scrambled to produce lines of spectrum, network and communications analyzers, oscilloscopes, power meters, electromagnetic field sensors, and many other types of products specifically for the cellphone and Wi-Fi industries, companies were scrambling to provide for the needs of FM radio and television development labs and production lines. This 1947 advertisement from Radio Corporation of America (RCA) is an example that appeared in Radio News magazine. In fact, TV was so new that just a few months later, in September of 1948, editor Hugo Gernsback changed the publication's name to Radio and Television News ...

Thin Nylon Films for Transparent Electronic Devices

Thin Nylon Films for Transparent Electronic Devices - RF Cafe"Very thin nylon films were created that can be used in electronic memory components. The films are several hundreds of times thinner than a human hair and could be used in bendable electronic devices or for electronics in clothing. Nylon synthetic polymers consist of a long chain of repeated molecular units in which each repeated unit contains a specific arrangement of hydrogen, oxygen, and nitrogen with carbon atoms. Besides use in textiles, some nylons also exhibit ferroelectric properties - positive and negative electric charges can be separated and this state can be maintained. The ferroelectric materials are used in sensors, actuators, memories, and energy-harvesting devices ..."

PCB Directory: Printed Circuit Board Fabrication & Assembly

PCB  Directory - RF CafePCB 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 (FR-4, Rogers, flexible, rigid), Geographical location (U.S., China), kinds of services (manufacturing, fabrication, assembly, prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.

Scatter Communication

Scatter Communication, August 1958 Radio News - RF CafeIf you are a Ham radio operator - especially a DX (long distance) operator, you have been required to study and learn about how the various layers of the Earth's ionosphere can, under predictable conditions, be an excellent reflector of certain radio wavelengths, thereby facilitating over-the-horizon communications. Reading this article is like a flashback from the license preparation manuals - particularly for the General license exam. There is a lot of information here. When this article was published in a 1958 issue of Radio & TV News magazine, the world was nearing the end of the International Geophysical Year (IGY), which had as its goal learning as much as possible about the properties of the upper atmosphere. The first earth-orbiting satellites were being launched and manned space flight was only months away, so there was much interest in learning ...

App Note: dB Or Not dB?

Rohde Schwarz App Note: dB Or Not dB? - RF CafeRohde & Schwarz has published an app note entitled, "dB Or Not dB?" (a rather contrived attempt - yet not unlike something I might try to get away with - at an allusion to Shakespeare's "To be or not to be..."). The subtitle is, "Everything you ever wanted to know about decibels but were afraid to ask..." It begins, "%, dB, dBm and dB (μV/m) are important concepts that every engineer should understand in his (or her) sleep. Because if he does not, he is bound to be at a disadvantage in his work. When these terms come up in discussions with customers or colleagues, he will have trouble focusing on the real issue if he is busy wondering whether 3 dB means a factor of 2 or 4 (or something else). It is well worth the effort to review these concepts from time to time and keep familiar with them ..."

Those Evil Radios!

May 29, 1948, edition of the Saturday Evening Post, because it contained one of Charles Schulz's Li'l Folks (which became Peanuts) comicsA while back, I purchased a May 29, 1948, edition of The Saturday Evening Post, because it contained one of Charles Schulz's Li'l Folks (which became Peanuts) comics. There were a couple things that stood out as I perused the magazine. First was the vitriolic tone of the Letters to the Editor, ripping the publication for articles in previous editions. Another was that the majority of the artwork for stories and advertisements was either a painting or a pencil drawing - almost no photographs. There was not a single ad for any television set - B&W or color - even though RCA had been selling color sets for four years by that time. The following story was on the last page of the magazine. You'll get a kick out of its premise ...

IEEE Symposium on Phased Array Systems and Technology

2019 IEEE International Symposium on Phased Array Systems and Technology - RF CafeThe 2019 IEEE International Symposium on Phased Array Systems and Technology will be held from October 15th through 18th at the Westin Hotel in Waltham, Massachusetts, on Boston's famous Route 128 Technology Highway. The symposium will include keynote and plenary sessions, parallel technical sessions, poster sessions, tutorials, and a student paper contest. Social events will include a welcome reception with dinner and an awards banquet. This symposium will present the most recent advances in phased array technology and provide a unique opportunity for members of the international community to interact with colleagues in the field of phased array systems and technology.

Report Analyzes RF Front End Components

Report Analyzes RF Front End Components - RF Cafe"After many years of continuous growth, the global smartphone market saw a slowdown in 2018. This slowdown had a direct impact on the RF Front-End market which also saw a decline in demand last year. According to a recent Yole Développement (Yole) report, 5G will come to the rescue and drive the RF Front-End market to grow at a CAGR of 8% from 2018 to 2025. The market was estimated to be USD $15B in 2018, and is expected to reach USD $25.8 billion by 2025. With LTE, RF front-end market growth came from carrier aggregation and MIMO technologies. 5G will augment RF front-end market ..."

Empower RF Systems: RF & Microwave Power Amplifiers

Empower RF Systems - RF CafeEmpower 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.

The Case for the Transistorized Multimeter

The Case for the Transistorized Multimeter, January 1968 Popular Electronics - RF CafeOnce upon a time, all non-passive electronic products and test equipment used vacuum tubes. Since tube diodes need a voltage bias, even something as simple as a rectifier circuit was "active." Even though modern day transistorized equipment has largely overcome most of the disadvantages of solid state versus vacuum tube, in the early days of silicon and germanium transistors and diodes issues like voltage and power handling and input impedance was a limiting factor to some applications. Until the advent of rugged and reliable field-effect transistor (FET) transistors, if you needed a very high input impedance for an oscilloscope or multimeter, a vacuum tube circuit was a necessity. A high impedance test instrument input is required with high impedance device under test (DUT) in order to avoid loading down ...

56th Annual AOC International Symposium & Convention

56th Annual AOC International Symposium & Convention - RF CafeThe Association of Old Crows is holding their 56th Annual AOC International Symposium Convention in Washington, D.C., on October 28-30. It is regarded as the industry's leading event and brings together nearly 2000 professionals from 30+ countries spanning industry, military, and government sectors. "Learn from subject matter experts and influencers from military, government, academia and industry who will speak to a multitude of topics around the theme of 'Building the EMS Enterprise.' Whether it is from a main stage keynoter, a breakout session panelist, or an Innovation Stage message, plan to walk away equipped with the latest developments in technology and governance in pursuit of EMS capability superiority. ..."

Delco Radio Advertisement - Control of the Air

Delco Radio Advertisement - Control of the Air, April 1945 QST - RF CafeHere is an advertisement for Delco radios that I scanned from my copy of the April 1945 QST magazine. "'Control the Air' has a new meaning today." That's the tag line referring to the need to dominate wireless communications in the effort to conduct effective warfare. Radio certainly wasn't a new science in 1945, but secure communications - including spread spectrum techniques - was a vital technique both for transmitting and receiving messages and for jamming the communication of our enemies. Even though Hollywood actress Hedy Lamarr and music composer George Antheil came up with the concept of frequency hopping spread spectrum in the early years of World War II, the U.S. Department of War stuck mostly with codebook encryption techniques ...

Avoiding Electrical Damage with Conductive Lubrication

Avoiding Electrical Damage with Conductive Lubrication - RF CafeThis article entitled "Avoiding Electrical Damage with Conductive Lubrication" appeared in the October 2019 edition of NASA's Motion Design publication. It highlights the new problems being faced by automotive design engineers as they replace 12 V electrical systems, which have been the standard for over half a century, with increasingly preferred 48 V systems. The motivation (pun not intended) is, among other things, to enable use of smaller gauge wire, and the resulting lower weight and expense, in the ever-increasing amount of electrical cabling in modern vehicles. The downside of a higher voltage is a larger difference of potential induces larger leakage currents in metallic components without bonded connections - as in bushings and ball bearings. Engineers and scientists are now developing conductive lubricants to help mitigate the problem ...

10-Qubit Register Breaks New Ground in Quantum Computing

10-Qubit Register Breaks New Ground in Quantum Computing - RF Cafe"Imperfections in diamond enable a 10-qubit register - a collection of qubits that can store data in a quantum computer - report researchers at Delft University of Technology in the Netherlands and Element Six in the UK. Their diamond-based system is capable of preserving an arbitrary single-qubit state for over a minute - a record for a solid-state qubit. The multiqubit register signifies important progress in quantum-information processing, which requires a large number of qubits. Realizing multiqubit registers is challenging for two reasons: the quantum gates require selective control of qubits, and unwanted interactions must be avoided ..."

Many Thanks to Anatech Electronics for Long-Time Support!

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. 

Triad RF Systems PCB Directory (Manufacturers)
QuinStar Technology (Millimeter Wave Solutions) - RF Cafe vidaRF Isolators & Circulators - RF Cafe
About RF Cafe
Kirt Blattenberger - RF Cafe Webmaster
Copyright: 1996 - 2024
    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 ...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:  AirplanesAndRockets.com