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Tech Industry Headlines - RF Cafe - Archive -

German Funding Ericsson 6G Microelectronics R&D

• FCC Levies Dual Fines over AM and FM Violations

• Low Demand for EVs Hurting Volkswagen

• China Beats U.S. in Global Scientific Hot Papers Ranking

• Electric Cargo Ships Making Waves [powered by unicorns and dragon's breath]

• Today is National Manufacturing Day in the UK

• European Semiconductor Regions Alliance Launched

• Energy Harvesting Module Generates Power from Noise

• Wearables Increase as Prices Slide

• Panasonic EV Battery Factory in KS Keeps Coal-Fired Power Plant Open

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Static Electricity and the Triboelectric Series

Static Electricity and the Triboelectric Series - RF CafeThe phenomenon of triboelectricity, or the generation of static electricity through friction, has been known to humans for thousands of years. It is one of the earliest observed electrical phenomena, and its discovery predates recorded history. History Ancient civilizations, including the Greeks and Egyptians, were aware of the properties of certain materials to become electrically charged when rubbed together. They used materials like amber (known as "elektron" in Greek, which is the origin of the word "electricity") to create small sparks or to attract lightweight objects such as feathers. The Greek philosopher Thales of Miletus (circa 624–546 BCE) is often credited with some of the earliest recorded observations of amber's electrical properties. The famous experiment involving rubbing amber with fur, which demonstrates triboelectric charging, was described by the Roman author Pliny the Elder in his work "Naturalis Historia" around 77 CE. Pliny noted that amber could attract small particles when rubbed, a phenomenon we now understand as static electricity. Over time, further experimentation and observations led to the understanding that various materials exhibited different tendencies to gain or lose electrons during friction. This knowledge eventually led to the development of the triboelectric series...¢€£

Semi-Automatic Ground Environment (SAGE)

Semi-Automatic Ground Environment (SAGE) system - RF CafeRF Cafe visitor Joseph B. just sent me a link to a Pocket website article entitled, "The Most Important Computer You've Never Heard Of." It is a great technical look in the rear view mirror of the success of the U.S. Air Force's (NORAD born in 1958) Semi-Automatic Ground Environment (SAGE) system which was designed and built to monitor the flights of both intercontinental ballistic missiles and hostile aircraft. It is a good follow-on to the "SAGE - Whirlwind Defense Quarterback Goes into Operation" article in a 1956 issue of Popular Electronics magazine I posted a while back, which was a forward look through the windshield (to continue my car vantage point metaphor). Plenty of photos are included of the vacuum tube-based AN/FSQ-7 digital computer - which still holds the record as the largest computer ever built. It used 49,000 vacuum tubes and 68K of 32-bit magnetic core memory. It operated at about 75,000 instructions per second.  Note all the military operators are high-ranking NCOs.

Laser Gyroscope Measures Tiny Variations Day Length

Laser Gyroscope Measures Tiny Variations Day Length - RF Cafe"Some days really are longer than others. And now scientists know by precisely how much. Using a laser gyroscope, scientists have measured variations in Earth's rotation rate smaller than a millionth of a percent. The technique could help scientists understand the complex flows of water and air that cause the tiniest of tweaks to the planet's spin. Earth's rotation isn't perfectly steady. The planet speeds up and slows down as it twirls, making a day slightly shorter or longer by several milliseconds. Many of those variations are well understood. For example, one such variation is caused by tidal forces, created by the gravitational pull of the moon and the sun, that deform the planet. Scientists know how to predict those effects on Earth's rotation...

TV Receiver Conversion for Velocity Modulation

TV Receiver Conversion for Velocity Modulation, April 1951 Radio & Television News - RF CafeVelocity modulation, aka deflection modulation, of electronic images was evidently considered by some engineers to be potentially disruptive technology when this article was published in the April 1951 issue of Radio & Television News magazine. You can see from the pictures that the result is an image that today's digital software would render with an "emboss" technique. More vertical relief seems to be generated with the analog velocity modulation technique compared to what my graphics program does when embossing the original photo. At the bottom of the page is a velocity modulation video demonstration found on YouTube...

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...

Many Thanks to San Francisco Circuits for Continued Support!

San Francisco CircuitsSF Circuits' specialty is in the complex, advanced technology of PCB fabrication and assembly, producing high quality multi-layered PCBs from elaborate layouts. With them, you receive unparalleled technical expertise at competitive prices as well as the most progressive solutions available. Their customers request PCB production that is outside the capabilities of normal circuit board providers. Please take a moment to visit San Francisco Circuits today. "Printed Circuit Fabrication & Assembly with No Limit on Technology or Quantity."

Mathematical Bafflers

Mathematical Bafflers, March 1965 Mechanix Illustrated - RF CafeThis March 1965 issue of Mechanix Illustrated is part of a huge boxful of vintage magazines I picked up at a local estate sale for $20. It also included Popular Mechanics, Science & Mechanics, and a few others. All of them were on my regular reading list back in the 1970 and 1980s. I have been going through them looking for useful content for "RF Cafe" and for my "Airplanes and Rockets" website. A book review was done for Mathematical Bafflers, by Angela Dunn. To whet readers' appetites, a few examples appeared, along with their solutions, all of which are provided here. A search of the Internet turned up a PDF copy of the entire Mathematical Bafflers book, in case you are interested in such things - which you probably are if you've read this far. I have to admit that even with reading the solution, I still do not understand Q1. For Q2, I first made a simple guess based on the stated bricklaying rates of the two workers, and got the correct number on the first try (pure luck, I'm sure)...

Radar Training in the Air Force

Radar Training in the Air Force, June 1949 Radio & Television News - RF CafeHere is a story near and dear to my heart. From 1978 through 1982, I trained for and worked on a ground-based, mobile air traffic control radar system (AFSC 303x1). The AN/MPN-13 & 14 systems had both airport surveillance (ASR) and precision approach (PAR) primary radars, identification friend or foe (IFF) secondary radar, and UHF and VHF communications radios. The AN/MPN-13 was contained in two trailers; air traffic controllers sat and worked within the operations ("ops") trailer where the radar electronics were located. It was very a cramped environment, particularly when maintenance was required. The AN/MPN-14 was basically an AN/MPN-13 with an additional separate, spacious, RAPCON trailer. Controllers worked there in an uncluttered space, removed from the primary electronics. Of course the radar displays and radio controls were in the trailer. Controllers worked there in an uncluttered space, removed from the primary electronics. Of course the radar displays and radio controls were in the RAPCON, but they, having mostly solid state circuitry, rarely needed service. The vacuum tube-based radars needed a lot of service, but worked amazingly well when everything was functioning properly...

Shape-Changing Smart Speaker Mutes Room Areas

Shape-Changing Smart Speaker Mutes Room Areas - RF CafeIn virtual meetings, it's easy to keep people from talking over each other. Someone just hits mute. But for the most part, this ability doesn't translate easily to recording in-person gatherings. In a bustling cafe, there are no buttons to silence the table beside you. The ability to locate and control sound - isolating one person talking from a specific location in a crowded room, for instance - has challenged researchers, especially without visual cues from cameras. A team led by researchers at the University of Washington has developed a shape-changing smart speaker, which uses self-deploying microphones to divide rooms into speech zones and track the positions of individual speakers. With the help of the team's deep-learning algorithms, the system lets users mute certain areas or separate simultaneous conversations, even if two adjacent people have similar voices. Like a fleet of Roombas, each about an inch in diameter, the microphones automatically deploy from and then return...

Calculations for Parallel and Series-Parallel Circuits

A.C. Calculations for Parallel and Series-Parallel Circuits, June 1944 QST - RF CafeWhen you read a lot of tutorials about introductory electronics on the Internet, most are the same format where stoic, scholarly presentations of the facts are given. Those of you who don't have enough fingers and toes to count all of the college textbooks like that which you have read know of what I speak. When hobby articles are written in a similar fashion, it can quickly discourage the neophyte tinkerer or maybe even a future Bob Pease. The ARRL's QST magazine has printed a plethora of articles over the years that are more of a story than just a presentation of the facts. My guess is the reason is because often the authors are not university professors who have forgotten how to speak to beginners. This article on basic calculations for AC series and parallel circuits is a prime example...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook 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...

Thanks for Alliance Test Equipment's Support!

Allied Test Equipment Products - RF CafeAlliance Test Equipment sells used / refurbished test equipment and offers short- and long-term rentals. They also offer repair, maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP, Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization with ability to source hard to find equipment through our network of suppliers. Alliance Test will purchase your excess test equipment in large or small lots. Blog posts offer advice on application and use of a wide range of test equipment. Please visit Allied Test Equipment today to see how they can help your project.

Electronics-Themed Comics

Electronics-Themed Comics, May 1961 Radio-Electronics - RF CafeOut of these five electronics-themed comics from the May 1961 issue of Radio−Electronics magazine, the one on page 64 is my favorite - very clever. Next in line is the page 96 comic with the two alligators; take a good look at the picture. Continuing, coming in at third is the page 60 comic, which servers to illustrate the expectations imposed on abused electronic servicemen of the era. I'm surprised anyone would do field service work. I knew a guy on Tilghman Island, on the southern Eastern Shore of Maryland, who owned and operated an electronics repair shop. He told a few good stories about interactions with feisty customers. The page 46 comic is funny, but is an old gag (maybe not so much in 1961, though). The page 114 comic is either just plain stupid, or I'm missing something. Links to hundreds of others are listed at the bottom...

Remote Monitoring for Canadian Armed Forces

Iridium and McQ Remote Monitoring for Canadian Armed Forces - RF Cafe"Iridium Communications is proud to announce its partner McQ in collaboration with designer and manufacturer Barnacle Systems, has introduced a remote monitoring solution for fixed assets in the Arctic supporting the Department of National Defense and Canadian Armed Forces. BRNKL Arctic Deploy is an innovative solution for the DND/CAF to monitor and secure ground-based assets operating remotely in the Arctic over Iridium's weather-resilient, truly global satellite network. An autonomous remote monitoring solution, BRNKL Arctic Deploy utilizes McQ CONNECT advanced sensors to transmit data, including alerts and short video clips, over Iridium Certus. The portable remote monitoring system uses McQ's rScene micro radar capable of vehicle and person classification, in tandem with computer-vision assisted live video streaming for motion and intruder detection. BRNKL Arctic Deploy includes enhanced situational awareness..."

Improving Plug-In Coils

Improving Plug-In Coils, February 1935 Short Wave Craft - RF CafeBefore plug-in crystals were widely available for band selection in radio receivers, LC tank circuits did all the frequency discrimination heavy lifting. Accordingly, owners often had a selection of swappable inductors on-hand to enable listening to a variety of shortwave transmissions. During the time period of this article in a 1935 Short Wave Craft magazine, new "all wave" radios were hitting the showroom floors that largely mitigated the need for swapping components for the most popular frequency bands. "Short wave listening" (SWL) was a big deal back in the day since it enabled anyone without an amateur radio license to tune into conversations going on all over the world. Most were content to merely listen, but many were inspired to obtain their licenses in order to be able to transmit as well...

Atwater Kent Model 649 All−Wave Radio

Atwater Kent Model 649 All-Wave 9 Metal Tube Superhet. Set Radio Service Data Sheet, November 1935 Radio-Craft - RF CafeFor more than a decade, I have been posting these Radio Service Data Sheets for radios and various other audio and visual electronics sets that appeared in vintage electronics magazines. This one for the Atwater Kent Model 649 all-wave, 9 metal tube, superheterodyne console radio set was published in the November 1935 issue of Radio Craft magazine. "All−Wave" radios were popular at the time because they provided access to shortwave bands so listeners could tune in foreign broadband stations - often with the rudimentary built-in antenna. Short Wave Listening (SWL) was actually a worldwide sport that had its own cadre of enthusiastic participants, including a dedicated magazine entitled Short Wave Listener. Tuning into the audio portion of television broadcasts was a big deal as well. Although not as popular today, there are still a few adherents remaining...

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeBanner Ads are rotated in all locations on the page! RF Cafe typically receives 8,000-15,000 visits each weekdayRF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 17,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. Your Banner Ads are displayed on average 225,000 times per year! New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. I also re-broadcast homepage items on LinkedIn. If you need your company news to be seen, RF Cafe is the place to be...

Many Thanks to Reactel for Their Long-Time Support!

Reactel Filters - RF Cafe

Reactel has become one of the industry leaders in the design and manufacture of RF and microwave filters, diplexers, and sub-assemblies. They offer the generally known tubular, LC, cavity, and waveguide designs, as well as state of the art high performance suspended substrate models. Through a continuous process of research and development, they have established a full line of filters of filters of all types - lowpass, highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact Reactel today to see how they might help your project.

What Does an Op Amp Do?

What Does an Op Amp Do?, October 1969 Popular Electronics - RF CafeHere is an 10-question quiz on the basics of operational amplifiers (aka op amps, or opamps, compliments of Mr. John Seginski, in the October 1969 issue of Popular Electronics magazine. The first commercial opamp, the μA709, was introduced by Fairchild Semiconductor in 1963. Five years later they released the μA741, which was the most famous opamp of the era; it is still widely used today. One of my electronics circuit courses in college (c1987) used the 741 as the basis for analyzing integrated circuits, and in particular, opamps. A couple companies offered vacuum tube operational amplifiers which combined two or more tubes along with some integrated leaded biasing and compensating components, and had a tube sock pinout on the bottom for plugging into a standard socket. The GAP/R K2-W, produced by George A. Philbrick Researches, is an example. It was commonly advertised in electronics magazines of the era. Today, just about everyone having any involvement knows the basic equations for calculating opamp gain for both inverting (Rfeedback/Rinput) and non-inverting (Rfeedback/Rgnd +1) configurations...

Mass Production of MXene Nanomaterial

Mass Production of MXene Nanomaterial - RF Cafe "Researchers developed an analysis model using magnetic transport characteristics of molecules attached to the surface of MXene. The establishment of a property prediction and classification system is expected to be utilized to produce uniform-quality MXene. Developed in 2011, MXene is a two-dimensional nanomaterial with alternating metal and carbon layers, which has high electrical conductivity and can be combined with various metal compounds, making it a material that can be utilized in various industries such as semiconductors, electronic devices, and sensors. To properly utilize MXene, it is important to know the type and amount of molecules covered on the surface. If the molecules covered on the surface are fluorine, the electrical conductivity decreases, and the efficiency of electromagnetic wave shielding decreases. However, since MXene is only 1 nm thick, it takes several days to analyze the molecule..."

American-Bosch 524A Radio Schematic

American-Bosch 524A Radio Schematic, June 1935 Radio-Craft - RF CafeLocating images of automobile radios from the 1930s through 1940s is a challenge. Sometimes one shows up on eBay, but those that do are usually in un-reconditioned condition, and often with missing components. Early car radios were composed of separate units holding the electronics, another for the power supply, and another for mounting in or under the dashboard. The antenna was often a rectangular loop run around the perimeter of the underside of the car or truck. This schematic for the American-Bosch 524A Automotive Radio appeared in a 1935 issue of Radio−Craft magazine. I found a very nice website - Antique Autoradio Madness - which has a large collection of schematics and photographs for automobile radio from all over the world. It does not have the exact model reported on here, but there was a lot of similarity between radios of the same vintage, so the information on this American Bosch model 624A shown in the thumbnail image to the left is probably quite like the model 524A...

TotalTemp VmSD144 N Thermal Platform Vacuum Chamber

TotalTemp Technologies VmSD144 N Thermal Platform Vacuum Chamber - RF CafeTotalTemp Technologies, a worldwide leading provider of research laboratory and production temperature chambers and thermal platform equipment, introduces their model VmSD144−N Thermal Platform Vacuum Chamber. The efficient advantages of thermal platforms are a natural for conductive heat transfer in high vacuum applications. With all the new hardware going into space, where service calls are rare, thermal vacuum testing is an important part of testing high altitude and satellite equipment. Affordable and configurable for your application. Simultaneous high vacuum and thermal testing without renting time at a test lab. Thermal platforms to fit your vacuum chamber or fully turn-key systems. Platform shown inside bell jar is 6.5” x 7.5”, other sizes and different bell jars available. Aerospace environmental testing in a thermal vacuum chamber allows for the exposing and weeding out potential problems due to extreme temperature and atmospheric pressure changes as experienced in space. With equipment destined for space, the stakes are much higher with the cost of a launch, chances of a failure could be catastrophic plus service calls in space have historically been very costly. The game of basic thermal testing in space is a little different than testing for land-based systems, mainly because the lack of heat transfer by air. The intentional and unintentional transfer of heat by convection makes a big difference from what could be common sense solution in an environment with air...

The Muzak Story

The Muzak Story, June 1955 Popular Electronics - RF CafeMost people probably associate "elevator music" with the Muzak format. It became a registered trademark in 1954, although Muzak broadcasting was around a couple decades before that. Muzak music has also played in doctors' offices, restaurants, government public service facilities, buses, retail stores, and even workplaces (to provide calm and cadence for workers). According to the Wikipedia entry, the term "Muzak " was coined by its inventor, George Owen Squier (Major General, ret.) as a play on the made-up term "Kodak;" i.e., "Muz" (music) + "ak." Over the years, a lot of scientific research went into Muzak's format including genre of music, tempo, silence ("dead") time, volume, etc. Muzak has changed hands many times, including to Westinghouse, until it finally declared bankruptcy in 2010. If you type "muzak.com" into your browser now, you get redirected to moodmedia.com. Rumors have it that rocker Ted Nugent tried to buy Muzak in 1986 just to shut it down because it represented "all that is uncool about music..."

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeBanner Ads are rotated in all locations on the page! RF Cafe typically receives 8,000-15,000 visits each weekdayRF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 17,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. Your Banner Ads are displayed on average 225,000 times per year! New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. I also re-broadcast homepage items on LinkedIn. If you need your company news to be seen, RF Cafe is the place to be...

Thanks to Temwell for Their Support!

Temwell (filters) - RF CafeTemwell is a manufacturer of 5G wireless communications filters for aerospace, satellite communication, AIoT, 5G networking, IoV, drone, mining transmission, IoT, medical, military, laboratory, transportation, energy, broadcasting (CATV), and etc. An RF helical bandpass specialist since 1994, we have posted >5,000 completed spec sheets online for all kinds of RF filters including helical, cavity, LC, and SMD. Standard highpass, lowpass, bandpass, and bandstop, as well as duplexer/diplexer, multiplexer. Also RF combiners, splitters, power dividers, attenuators, circulators, couplers, PA, LNA, and obsolete coil & inductor solutions.

Radioptics Forecast

Vintage "U.F.O." fiber optic lamp - RF CafeIn a 1963 editorial in his Radio−Electronics magazine, Hugo Gernsback dubbed electromagnetic wave frequencies above 300 GHz as "radioptics."Today, we refer to them as the sub-millimeter bands, or terahertz bands. The visual spectrum runs from around 0.63 mm (red, 630 nm, 6300 Å) to 0.36 mm (blue, 360 nm, 3600 Å). Again, Mr. Gernsback shows himself to be a prolific futurist and visionary. He was more than "all talk and no action," as he possessed many patents for his inventions and produced some build-it-yourself electronics kits. That was in addition to being a prolific writer and publisher of both fact and fiction. At the time of this article, fiber optics was a fledgling technology from a practical application standpoint. It was used in some critical communications applications due to its security advantages (difficult to tap), but in the commercial realm, those decorative multicolor fiber optic lamps were about it until laser semiconductors hit the shelf. Today, optical fiber is quickly replacing metallic conductors everywhere, most notable for Internet infrastructure...

RF Workbench™ Major Update:

RF Workbench - the world's most downloaded RF Cascade program! - RF CafeNow you can launch my classic "RF Workbench" program directly into DOSBox!!! I believe I have figured out a way to launch RF Workbench directly into a DOSBox emulator screen, without needing to first install DOSBox, mount a hard drive, and then launch the program file. Instead, simply unzip the "RFWB_DOSBox [unzip into Program Files (x86) folder].zip" file into your "Windows\Program Files (x86)" folder. Then, double-click on the "RFWB−DOSBox−Launch shortcut link" (.lnk) shown highlighted below left. Click one of the "RFWB 4.0" icons to download.

Mac's Radio Service Shop: Pride and Prejudice

Mac's Radio Service Shop: Pride and Prejudice, April 1955 Radio & Television News - RF CafeThere's not a much better way to finish up a hard week at the office than reading a new episode of John T. Frye's "Mac's Radio Service Shop." Mac McGregor and his trusty sidekick technician Barney tackle nearly every issue associated with an electronics sales and service establishment back in the heyday of radios and televisions. You might recognize the title of "Pride and Prejudice" as being borrowed from Jane Austin's classic, which, to summarize, deals with, well, pride and prejudice based on one's social status, and how it results in lost opportunities. To be honest, I have not read the book but I did see the movie version starring Keira Knightly. Anywho, you'll need to read the second half of the story to get to the actual pride and prejudice part. As for the first part, it might be difficult to imagine what all the fuss is over tape recorder usage (or non-usage as is the case here), but remember that in 1955 it meant a case with vacuum tubes and requisite heavy transformers...

Concrete + Carbon Black Supercapacitor

Concrete + Carbon Black Supercapacitor Promises Large-Scale Energy Storage - RF Cafe"MIT researchers analyzed and evaluated low-cost, easily fabricated supercapacitors that potentially offer high capacity plus structural strength. The high-density energy stage has always been a challenge, whether accomplished using electrochemistry and batteries, electric fields and supercapacitors, gravity-based systems of various types, or any of the many other options. Now, a team of researchers at MIT and the affiliated Wyss Institute for Biologically Inspired Engineering claims to have devised a technical and cost-effective solution using relatively mundane materials: concrete, carbon black, water, and potassium-chloride salts. Their approach uses a cement-based material with an extremely high internal surface area due to its dense, interconnected network of conductive material within its bulk volume. The researchers achieved this by introducing carbon black - which is highly conductive - into a concrete mixture along with cement powder and water, and letting it cure..."

Hams in Combat: A Lady of Mercy

Hams in Combat: A Lady of Mercy, July 1944 QST - RF CafeThis is another installment of the Hams in Combat series that QST magazine ran during WWII. I enjoy waxing vicariously nostalgic of a time before I was born, at time when there was still honor, courage, selflessness, and pride of country. During World War II, it was an ingrained part of most citizens, whether or not they happened to be serving in the military. Our modern day troops still have it, but sadly fewer and fewer people see their own country as any place special in the world. Sure, as General William Tecumseh Sherman famously said, "War is hell," but then again so is witnessing the tearing apart of your country from forces within - an "enemy at the gates," or a "fifth column," so to speak...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook 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...

Please Thank Werbel Microwave for Continued Support!

Werbel MicrowaveWerbel Microwave is a manufacturer of RF directional and bidirectional couplers (6 dB to 30 dB) and RF power dividers / combiners (2− to 16−way) with select models operating up to 26.5 GHz and 100 W of CW power (3 kW peak). All are RoHS and REACH compliant and are designed and manufactured in our Whippany, NJ, location. Custom products and private label service available. Please take a couple minutes to visit their website and see how Werbel Microwave can help you today.

Electronics Theme Crossword for September 24th

Electronics Theme Crossword Puzzle for September 24, 2023 - RF CafeThis week's crossword puzzle for September 24th sports an electronics theme. This being the twenty−fourth day of the month, many of the words begin and/or end with and/or contain the letter "X." Expect a few repeats, since words with and "X" in them are harder to come by. All RF Cafe crossword puzzles are custom made by me, Kirt Blattenberger, and have only words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects. As always, this crossword 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., Reginald Denny, Hedy Lamarr, or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort...

Get Your Custom-Designed RF Cafe Gear!

Custom-Designed RF-Themed Cups, T-Shirts, Mouse Pads, Clocks (Cafe Press) - RF CafeThis assortment of custom-designed themes by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins, Purses, Sweatshirts, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We Are the World's Matchmakers" Smith chart design. These would make excellent gifts for husbands, wives, kids, significant others, and for handing out at company events or as rewards for excellent service. My graphic has been ripped off by other people and used on their products, so please be sure to purchase only official RF Cafe gear. I only make a couple bucks on each sale - the rest goes to Cafe Press. It's a great way to help support RF Cafe. Thanks...

Thanks to Aegis Power Systems for Their Continued Support!

Aegis Power Systems - RF CafeAegis Power Systems is a leading supplier of AC-DC and DC-DC power supplies for custom and special applications. Aegis has been designing and building highly reliable custom power supplies since 1995. They offer a complete line of switch mode power supplies and power converters for a variety of markets including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft, EV, telecom, and embedded computing applications. Design and manufacture of custom power supply solutions to meet each customer's exacting specifications. Please visit Aegis Power Systems today. Manufactured in the USA.

Electronic "A" Quiz

Electronic "A" Quiz, April 1968 Popular Electronics - RF CafeHere is an Electronic "A" Quiz for you to test your knowledge of terms, compliments of Popular Electronics quizmeister Robert P. Balin. The number of spaces is equal to the number of characters needed in addition to the leading "A" to spell the word. About half of them are easily identified, but the others might take some head scratching - particularly numbers one and four (hint: four has to do with vacuum tubes). Number seven's illustration could be better, so don't feel bad if you don't get it (I didn't), because it is a phenomenon only seen on cathode ray tube (CRT) displays, not on LCDs. The word "amplifier" fits for number eight, but that is not the answer sought. My score with only a couple minutes of consideration was a paltry 6:10.

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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 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 tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

Copyright  1996 - 2026

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

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:


KR Electronics (RF Filters) - RF Cafe

everythingRF RF & Microwave Parts Database - RF Cafe

Innovative Power Products Passive RF Products - RF Cafe