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World's 1st Quantum Entanglement Communications Service

World's First Quantum Entanglement Communications Service Offered by QentComm - RF CafeIn a groundbreaking announcement that will forever transform global communications, QentComm®©™ (Quantum Entanglement Communications) has unveiled the world's first commercially viable quantum entanglement communication system. Dubbed QeG®©™ (Quantum entanglement Generation, pronounced kwee-gee), supplementing the traditional 4G, 5G, and 6G nomenclature, this revolutionary technology eliminates the limitations of traditional radio-based systems, delivering instantaneous, unlimited connectivity across any distance without reliance on satellites, cell towers, or fiber optics. Under the leadership of Kirt Blattenberger, QentComm (pronounced kwent-kōm) has created a system that defies conventional physics by utilizing quantum entanglement for real-time, secure communication between devices anywhere in the universe - including here on Earth...

Carl & Jerry: Secret of Round Island

Carl & Jerry: Secret of Round Island, March 1957 Popular Electronics - RF CafeIn this "Carl & Jerry" technodrama from a 1957 issue of Popular Electronics magazine, the two boys start out enjoy a casual day of kite flying, using a homebrew radio-controlled camera attached to the kite to capture an aerial view of Round Island in a lake. After successfully taking a picture, they develop the film and discover two men and an odd setup on the island. Curious, they return the next day, find a hidden tunnel, and stumble upon an illegal liquor still. As you might expect, the teens run into a heap of trouble when the moonshiners nab them. Using their combined ingenuity and knowledge of communications methods common to Ham radio operators of the era, contact was made and help was on the way. Read about Carl and Jerry's exploit and exactly what it was that saved the day - and their hides!

Ham Radio Students at DSES Radio Telescope

Amateur Radio Students Visit DSES Radio Telescope - RF Cafe"In late January 2025, 17 students and staff members from Las Animas High School (LAHS) in Colorado visited the Deep Space Exploration Society Radio Telescope (DSES) located at the Plishner Radio Astronomy and Space Sciences Center near Haswell, Colorado. They also got an introduction to amateur radio. 'This first field trip visit of high school students reflected the dreams of Michael Lowe, former DSES board president, who sought to create a center for radio astronomy and space science education in southeast Colorado,' said DSES President Myron Babcock, KL7YY..."

Old World Standards Breaking Through

Old World Standards Breaking Through, April 1966 Popular Electronics - RF CafeMaking format changes to magazines after many years of an established standard always ruffles the figurative feathers of a significant portion of regular readers. Two magazines I read monthly, Model Aviation and QST, recently underwent a format change - both of which I considered very nice. However, reader comments in the aftermath showed a few who were not impressed. Popular Electronics magazine in 1966 made announcements regarding plans to adopt some of the newer base units for physical measurements, including this one for beginning to use "Hertz" (Hz), along various numerical prefix forms, instead of "cycles per second" (cps). The editors give sound reason...

Harold Beverage of the Eponymously Named Antenna Type

Harold Beverage of Eponymously Named Antenna Type, August 1944, Radio-Craft - RF CafeThe Beverage Antenna, very familiar to amateur radio operators, is a simple but efficient, highly directional, non-resonant antenna that consists of a single straight wire of one or more wavelengths that is suspended above the ground. It is orientated parallel to the direction of intended reception. One end is terminated to ground through a resistor, and the other is connected to the receiver. The following quote comes from the patent (US1,81,089) text: "In accordance with theoretical considerations, if an antenna were to be freely suspended and if the surface of the earth constituted a perfectly conducting parallel plane, current waves would travel through...

Dear Mr. Fips: 30-Day Record Response

Dear Mr. Fips: 30-Day Record Response, June 1961 Radio-Electronics - RF CafeThis letter was sent to Hugo Gernsback, publisher of Radio-Electronics magazine, in response to the "30-Day Record Response" article penned by noted scientist and inventor Mohammed Ulysses Fips. In it, Stephen A. Kallis, Jr. heaped laud upon the "Most Revered and Esteemed Fips" for his long-term recording device (remember, 1961 was many decades before microminiature terabyte memory and microprocessors) were available, and chastises Mr. Gernsback for evidently calling into question the authenticity of the recorder. Kallis, a self-proclaimed stereo enthusiast, bolsters Fips' case by citing "A Proposed Listening Area," by the Institute of Synergistic Statics Proceedings...

Ulano Masking Films - Rubylith

Ulano Masking Films, December 27, 1965 Electronics Magazine - RF CafeRaise your hand if you're old enough to remember doing printed circuit board layout using Rubylith tape. My hand is up. Back in the early 1980s, I did prototype PCB designs in an engineering development lab at Westinghouse Electric's Oceanic Division. Most of it was for analog and RF substrates that would be photographically reduced in size for use with bare integrated circuit die and surface mount passive components (Rs, Ls, and Cs), upon which I would later epoxy-mount those components and wire-bond everything using 1-mil gold wire. However, there were projects where full-size leaded components were used on a through-hole PCB that used not only the Rubylith tapes but also sheets with special electronics shapes for solder pads around the holes for components leads, ground and power planes, board-edge connectors...

Mind-Bending Quantum Phase Flip

Mind-Bending Quantum Phase Flip - RF Cafe"Quantum systems don't just transition between phases - they do so in ways that defy classical intuition. A new experiment has directly observed these dissipative phase transitions (DPTs), revealing how quantum states shift under carefully controlled conditions. This breakthrough could unlock powerful new techniques for stabilizing quantum computers and sensors, making them more resilient and precise than ever before. A new frontier phase transitions, like water freezing into ice, are a familiar part of everyday life. In quantum systems, however, these transitions can be far more extreme, governed by principles like Heisenberg's uncertainty..."

DX Hams Do Get Around

DX Hams Do Get Around (November 1940 Boys' Life Article) - Airplanes and RocketsIn this November 1940 issue of the Boy Scouts Boys' Life magazine, amateur radio operators, or "hams," are described as having the ability to communicate across vast distances, connecting far-flung locations such as Goulds, Florida, Cali, Colombia, Cairo, Kenilworth, England, Bombay, and Brisbane. These operators, licensed by the Federal Communications Commission, engage in various activities such as talking to distant stations, participating in contests, and providing emergency communication during natural disasters. With call letters assigned by international treaty, these stations use a combination of code and phone to make contact, exchanging reports and QSL cards. The Radio merit badge was first offered in 1918 and has been...

Thanks Again 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! 

Electronic Razor

Electronic Razor, April 1962 Radio-Electronics - RF CafeThe date approacheth when, according to Western customs, every body needs to stand a vigil against the attempt of another body to make him or her a fool. That date is of course April 1st, aka, April Fools' Day. Many of the technical magazine we grew up with - and some still today - engage in the ruse. Innovator and publisher Hugo Gernsback, who's long list of accomplishments includes this Radio-Electronics magazine, often contributed his own wit to the April editions. The usual scheme is to make the article just authentic enough to be possibly real, while including features outrageous enough to clue the read that he is being "had." Experienced subscribers knew that the Mohammed Ulysses Fips byline was sure to deliver an April Fools delight. Here, Mr. Fips expounds on the newfangled "Electronics Razor..."

Photon Entanglement Miniaturizes Quantum Computers

Photon Entanglement Miniaturizes Quantum Computers - RF Cafe"Quantum computing has long struggled with creating entangled photons efficiently, but a team of researchers has discovered a game-changing method using metasurfaces - flat, engineered structures that control light. By leveraging these metasurfaces, they can generate and manipulate entangled photons more easily and compactly than ever before. This breakthrough could open the door to smaller, more powerful quantum computers and even pave the way for quantum networks that deliver entangled photons to multiple users..."

Waveguide Temperature Rise

Temperature Rise in Rigid Waveguide, January 17, 1964 Electronics Magazine - RF CafeHere is a chart you don't see every day - "Temperature Rise in Rigid Waveguide." The company, Engineering Antenna Systems, of Manchester, New Hampshire, that published the chart in a 1965 edition of Engineering magazine, does not exist anymore. They were probably bought by someone else, but I could not even find an honorable mention of them in a Google search. Given the very low attenuation of properly sized and installed waveguide, it is hard to imagine a temperature rise of 500°F; however, when megawatts are pumped into it even a couple tenths of a decibel of attenuation per 100 feet results in a lot of power loss. Noted is how attenuation - and therefore temperature rise - is greater for frequencies at the lower end of the waveguide's operational range. Temperature rise numbers are for natural convection in free air...

everything RF Interviews Ernest Werbel

everything RF's Interview with Ernest Werbel from Werbel Microwave - RF CafeHere is an inspiring interview of Werbel Microwave's Ernest Werbel - a case of pulling oneself up by one's own bootstraps --- everything RF recently interviewed Ernest Werbel, the Chief Design Engineer of Werbel Microwave. He is from Livingston, NJ, and got his associates in EE Technology, at County College of Morris. Ernest completed his Bachelors in Electronics and Computer Engineering Technology from NJ Institute of Technology. He founded Werbel Microwave in 2014. Q. Can you tell us about Werbel Microwave? When did you start the company and how has it evolved over the years? Ernest Werbel: Firstly, thank you for the opportunity to participate in the everything RF community. I appreciate everything that Raghav and his team have done for us since the beginning, getting our products listed on everything RF and featuring our products in the email blasts... As a child and teen in the 90s, I was always interested in electronics. When I was very young, a radio was a magical box with a voice. Later, when my grandparents passed in '97, my parents and I were cleaning out their home in Brooklyn. Among other things were many old and broken consumer electronic items...

Have You Seen Him?

Have You Seen Him?, April 1935 Short Wave Craft - RF CafeToday we have missing persons notices printed on milk cartons and computer-aged pictures of missing kids on bulletin boards at Walmart, and of course the Internet with all its various forms of publicity. In 1935, evidently, an electronics magazine was a proper venue for placing a missing person ad. At the time there was no convenient and accessible way for family members to reach out to a nationwide audience other than to place ads in magazines and/or newspapers in remote locations. I thought it odd to see such a placement in this edition of Short Wave Craft magazine, but considering the aforementioned, doing so is entirely reasonable for a worried family. I wonder how much it cost to place the notice? It's heartbreaking, really...

Engineering & Tech Headlines <Archives>

• 2025 Tech Jobs Expected to Take Off

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• 76% of News Consumers Still Use AM/FM

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• Radio Attracts High Purchasing Power Consumers

Turn Your Vertical Antenna into a Rotatable Beam

Turn Your Vertical Antenna into a Rotatable Beam (QST) - RF CafeI'm always aware of the old saying that it is better to remain silent and thought a fool, than to open your mouth and remove all doubt, but I'll take the risk here. The ARRL's QST magazine has for decades in the April issue published at least one unannounced "April Fool" item. I think I found at least two for 2025. While enthusiastically reading "Turn Your Vertical Antenna into a Rotatable Beam," (p60), it didn't occur to me that this was the April issue, and I was in awe of Jay Kolinsky's (NE2Q) intuition and creativity in devising a scheme to get directivity from his standard vertical whip antenna. By sliding a carbon fiber tube with a narrow slit along the length over top of the antenna, a 14 dB increase was realized in the direction of the slit. NE2Q has named his invention the Loof Lirpa Slot (LLS). What's in a name - Juliet?. Is a patent in the works?
CW Corporation of America's "Snappy Training Key" - RF CafeThe other suspect is the CW Corp. of America's "Snappy Training Key," reported on page 95 by Ellwood Brem (K3YV). You need to log in to read the articles, or borrow a hard copy from a Ham friend.

Unbreakable 13,000 km Quantum Link Beam

Unbreakable 13,000 km Quantum Link Beam - RF Cafe"A major scientific leap has been made with the creation of the longest ultra-secure quantum satellite link between China and South Africa, spanning nearly 13,000 km. This unprecedented achievement, marking the first quantum satellite link in the Southern Hemisphere, relied on real-time quantum key distribution to transmit encrypted images between continents. World’s Longest Quantum Satellite Link Established Scientists from South Africa and China have successfully created the world’s longest intercontinental quantum satellite link, spanning 12,900 kilometers (~8,000 miles). This ultra-secure connection was made possible using China's Jinan-1..."

Radiocarbon Nuclear Battery Lasts a Lifetime

Radiocarbon Nuclear Battery - RF CafeAccording to the science and mechanics magazine I read during the 1960s through 1980s, we should all have personal nuclear power generators powering our houses, watches, cars, and just about anything that runs on electricity. Like with flying cars and robotic domestic servants, were not even close to that a quarter of the way through the next century (2025). This news item appears to be a good start on the promise. "Imagine never charging your phone again or having a pacemaker that lasts a lifetime. Scientists are developing tiny nuclear batteries powered by radiocarbon, a safe and abundant by-product of nuclear plants. Unlike lithium-ion batteries, which degrade over time and harm the environment, these new designs use beta radiation to trigger an electron avalanche and generate electricity. The technology could one day make nuclear power as accessible as your pocket device..."

FM Radio Quiz

FM Radio Quiz, April 1950 Radio & Televsion News - RF CafeFM (frequency modulation) radio certainly was a hot topic beginning in the middle to late 1940s. With the war out of the way, energies and resources were being redirected back to peacetime production. Major Edwin Armstrong announced his FM scheme in 1935, and as with many new inventions, it was met with skepticism by many who doubted his claim of static interference immunity. For many, it was a lack of understanding that caused the negative reaction, caused primarily by the increased level of sophistication of the transmitter and receiver circuitry. Amplitude modulation (AM) was so easy even a caveman could understand it, but adding phase relationships into the equation (literally) left many in the dust. This FM Radio Quiz from a 1950 issue of Radio & Television News magazine tests your grasp of frequency modulation principles...

Archie's Ham Radio Adventure

Archie's Ham Radio Adventure - RF CafeStan Goldberg is a familiar name to comic book aficionados for his artistry in Spider Man, the Incredible Hulk, and the Archie series. QST magazine had him listed in the "Silent Keys" column in the November 2014 issue because he passed away in August. A Silent Key, in Hamdom, is usually a title reserved for a deceased licensed operator (the 'key' reference being a Morse code key), but a search of the Internet and the FCC license database web page did not turn up a call sign for him. Unless his record has been dropped from the database, Mr. Goldberg might never have actually been a Ham, but earned the Silent Key acknowledgement because of his involvement in a 1986 special edition comic book titled "Archie's Ham Radio Adventure." It was quite an extensive story...

Storage Battery Could Bring Back Electric Autos

Tech Notes: New Storage Battery Could Bring Back Electric Autos, December 1966 Radio-Electronics - RF CafeIn a 1966 issue of Radio-Electronics magazine, a revolutionary sodium-sulfur storage battery was demonstrated at a Detroit press conference, suggesting that Ford could enter the electric car market within the next ten years, and in the process "bring back electric autos." That suggests there were EVs before, and in fact, there were, at the turn of the 20th Century. The new battery, operating at 800° Fahrenheit, was completely sealed and produced 15 times more power than a lead-acid battery of the same weight, without the need to vent charging gases. The battery's design featured sodium and sulfur separated by a ceramic partition, with sodium ions moving through the ceramic to form sodium sulfide during discharge and reversing the process during charging, producing no gases or byproducts...

Electronic Current Quiz

Electronic Current Quiz, October 1963 Popular Electronics - RF CafeThis Electronics Current Quiz from the October 1963 edition of Popular Electronics magazine is recent enough (if you consider more than half a century ago to be recent) that it uses both transistors as well as vacuum tubes in the example circuits. I have to admit to only scoring 60% on the quiz, which is pretty lame. You will probably do better, especially if you are my age or older. I thought the names of the current type would make the challenge a breeze, but not so in my case. Just as back in school days when looking up the solution to problems in the back of the textbook and the answers seem obvious (well, not always), so, too, do these...

Photonic Chip Transforms Radar and Comms

Photonic Chip Transforms Radar and Comms Systems - RF Cafe"Researchers at the University of Twente, in collaboration with the City University of Hong Kong, have designed a cutting-edge programmable photonic chip in a thin-film lithium niobate platform, an important material in photonics. Published in Nature Communications, this work paves the way for next-generation high-performance radar and communication applications. An important material is changing the way optical chips work, making them smaller, faster, and more efficient: thin-film lithium niobate (TFLN). It offers exceptional properties for how light and electrical signals can interact..."

Alexander Graham Bell: A Short Bio

Alexander Graham Bell: A Short Biography - RF Cafe - RF CafeAlexander Graham Bell was born on March 3, 1847, in Edinburgh, Scotland, to Alexander Melville Bell and Eliza Grace Symonds. His father was a professor of elocution and the inventor of Visible Speech, a system designed to help deaf people communicate. His mother, Eliza, was an accomplished pianist who lost her hearing later in life. Bell was the second of three children; his brothers, Melville James and Edward Charles, both died of tuberculosis. Bell's early education was influenced by his father's work in speech and elocution. He attended the Royal High School in Edinburgh and later studied at the University of Edinburgh, though he did not complete a degree. His family moved to London in 1865, where Bell continued his studies at University College London, focusing...

$5.00 for Best Short Wave Kink

$5.00 for Best Short Wave Kink, November 1935 Short Wave Craft - RF CafeHere is a handy-dandy baker's dozen of "kinks," otherwise known as tricks of the trade, shortcuts, or clever ideas, that could prove useful while working in the lab at work or in your shop at home. They appeared in a 1935 issue of Hugo Gernsback's Short Wave Craft magazine. One suggestion is to place a sheet of tracing paper over your schematic while wiring a circuit and draw each connection as it is completed, rather than mark up the original drawing. That was definitely good for a time when making a spare copy of a magazine page or assembly instruction from a kit was not as simple a matter as it is today. Whether it be a schematic or a set of plans for a model airplane, I always make a copy to work and draw notes on rather than defacing the original...

Do You Know the Law?

Do You Know the Law?, November 1963 Radio-Electronics - RF CafeThis quiz from a 1963 issue of Radio-Electronics magazine tests readers' familiarity with key electrical laws beyond the well-known Ohm's Law, including Kirchhoff's voltage and current laws for circuit analysis, Joule's law for heat in resistors, Poynting's theorem for energy flow, Lenz's law for induced forces, Neumann's formula for transformers, Wien's displacement law impacting infrared electronics, Helmholtz's theorem for vector fields, the Wiedemann-Franz-Lorentz law connecting conductivity types, and Faraday's law of induction, challenging engineers to recall these foundational principles and their discoverers. Well, it is not exactly a quiz as much...

Today in Science History

Today in Science History - RF Cafe

Frequency-to-Meter Conversion Chart for Hams & SWL's

Frequency-to-Meter Conversion Chart for Hams & SWL's, June 1966 Popular Electronics - RF CafeAs with your school and college days where once there was no longer any reason to memorize physical constants, conversion formulas, and names of people, places, and things, much of the noggin's gray matter was repurposed to remember topics of more immediate need. You can always look up what you have forgotten. While studying for your Ham radio or FCC license, being able to be able to quickly convert between wavelength and frequency is essential. Recalling on demand frequency-wavelength pairs is a real time saver on a timed exam. Even being able to perform the conversion on a calculator during the test takes up valuable time that could be better used on other tasks. This handy-dandy chart for converting...

TV Service Can Be Successful

TV Service Can Be Successful, February 1953 Radio-Electronics - RF CafeNote the byline in this 1953 Radio-Electronics magazine article - Juliette Drut (she's on the cover). Not often were articles in electronics trade magazines penned by a dame or damsel back in the day. For that matter, it's still pretty rare today... hmmm... but I digress. If you thumb through any electronics magazines from the middle of the last century, you find that the pages are filled with advertisements offering courses to train prospects in the field of television and radio repair, with promises of a potential to make big money. Both institutional and home-study courses abounded. The costs never appeared, but hey, with the money a fellow would be making soon, surely the price would be inconsequential. Interestingly, in those same issues would be articles such as this one addressing the reality of electronics servicing...

Making Circuit Components

Making Circuit Components, July 1969 Radio-Electronics - RF CafePart 1 of this "All About IC's" trilogy titled, "What Makes Them Tick," author Bob Hibberd introduced the concept of semiconductor physics and doped PN junctions. In Part 2, he discusses methods used to fabricate monolithic, integrated circuits (IC's) on silicon chips. Transistors, diodes, resistor, capacitors, and to some extent, inductors, can be built using a combination of variously doped junction regions, metallization, and oxidation (insulators). Technology has come a long way since 1969, including mask techniques, 3-D structures, doping gradients, feature size, dielectric breakdown strength, current leakage, circuit density, mixed analog, RF, and digital circuitry, and other things. Part 3, covered in the August issue, goes into more detail about how passive components are realized in silicon...

Coaxial Cable Equations

Coaxial Cable Equations Formulas - RF CafeMost professional engineers and technicians will never have the need to calculate the capacitance, inductance, or impedance of a coaxial cable since they are usually designing systems using well-defined components that are manufactured to exacting specifications. Students, hobbyists (Ham radio operators), and research types are probably the ones most likely to actually plug numbers into a calculator. For those people, I present these equations. Be very careful to realize that at frequencies far from DC, factors like skin depth and effective inner and outer conductor diameters may be significantly different than the physical measured values, and that can significantly affect real world results. Therefore, be sure to consult manufacturers' published data before making a final decision. I leave it to other sources to provide the complex equations needed to precisely model coaxial cables...

A Look at the PC Market

A Look at the PC Market, January 1972 Popular Electronics - RF CafeWhen I first read the title for this article, "A Look at the PC Market," I was thinking personal computers, not printed circuits. It being from a 1972 issue of Popular Electronics, my assumption was that the photos of circuit boards were from early kit format computers, but then it finally dawned on me that there were no personal computers in 1972 - not even in kit form. Actually, that is not entirely true since there were advertisements for hokey contraptions called "computers" that combined some switches, logic gates, and LEDs for implementing simple multiple choice true/false testing boxes or rudimentary (with emphasis on "rud[e]") calculators. Getting to the real story, though, the 1970s was the decade where printed circuit boards (PCBs) were replacing point-to-point wiring wherever possible. If you opened a radio or television...

AM/FM Under Siege

AM/FM Under Siege - RF CafeThe electromagnetic world sure is a noisy place and it is getting worse all the time - in every region of the spectrum. Intentional radiation is not so much of a problem because it usually falls within well-defined limits and is predictable, but sloppy engineering and, honestly, ignorance, has made life harder for just about everyone. Listeners to broadcast radio in both the AM and FM bands have really taken a hit. AM has always been prone to interference by its very nature, so anyone listening expects the occasional pop or hiss from atmospheric phenomena or a light switch being flipped on or off. Have someone in the house run a blender or drill and you can forget hearing anything until the task is completed. It comes with the territory, so to speak. FM was and is largely immune to most forms of interference, but lately I have been noticing it coming from some of the most unusual places. For as long as I can remember, I have preferred to have a radio on in the background whilst whiling away at work and at play...

Vintage Watkins-Johnson Tech Notes Additions & Updates

Vintage Watkins-Johnson Tech Notes Additions & Updates - RF CafeThanks to Chuck U. for providing new Watkins-Johnson (WJ) Tech Notes v10-3 and v15-2, and an improved copy of v5-2. A lot (but not all) of the TNs that I had or other people sent to me are made from B&W copies from old scanners, so the quality is not super good. Chuck's versions appear to be scanned from the originals in color, so they're very good...

Coil Function Quiz

Coil Function Quiz, June 1962 Popular Electronics - RF CafeHere is a quick, 10-question electronics-themed quiz about coils (inductors). It appeared in the June 1962 edition of Popular Electronics magazine. Don't be scared off by the vacuum tubes that appear in three drawings. Just pretend they are transistors - it won't affect your answers. One of the coil applications is almost obsolete for most people as the nature of computer monitors and TV screens has changed significantly in the last decade...

U.S. Television Stations and Network Links Map

U.S. Television Stations and Network Links Map, May 1952 Radio & Television News - RF CafeIf my counting is correct, by 1952 only 33 of America's 48 states (Hawaii and Alaska weren't admitted until 1959), and Washington, D.C., had television broadcasting stations. That most of the early television experimentation occurred on the east coast is apparent by looking at the number of stations there compared to the west coast. You might think California would have the largest amount of TV stations, but it only had 11 located in 3 cities. New York, on the other hand, had 13 in 7 cities. Ohio had 12 stations in 5 cities, and Pennsylvania had 7 stations in 5 cities, one of which was my town of Erie. Vermont, New Hampshire, Mississippi, Wyoming, both Dakota, and Oregon were among those with no television stations by 1952. That seems unbelievable since that was only 67 years ago, but evidently was so. The network "lines" included microwave repeaters to reach from coast to coast. On September 4, 1951, AT&T opened the network by televising a presidential address...

The Klystron - Sperry Gyroscope Company

Klystron - Sperry Gyroscope Company, November 1944 Radio News - RF CafeDid you know that Sperry was assigned a trademark on the term "klystron?" The klystron vacuum tube type was actually invented by invented in 1937 by American electrical engineers Russell and Sigurd Varian (I'm old enough to have had Varian Associates catalogs). According to this full-page advertisement in a 1944 issue of Radio News magazine, not only did Sperry develop the klystron vacuum tube, but they also coined a term to describe any study or application of it: "klystronics." Here is a very interesting excerpt from the Wikipedia page, "The work of physicist W.W. Hansen was instrumental in the development of the klystron and was cited by the Varian brothers in their 1939 paper...

New Crystron Lapel Radio

New! Crystron Lapel Radio, April 1947 Radio-Craft - RF CafeAdmittedly, with all the reading I have done of vintage electronics magazines, news of this Crystron (crystal-electron) vacuum tube device invented by Mr. Mohammed Ulysses Fips, as reported in the April 1947 issue of Radio Craft magazine, evaded my attention. The article came only a couple months after publication of the 40th anniversary edition that celebrated Dr. Lee de Forest's invention of the Audion tube. According to Mr. Fips, his Crystron one-upped the Audion by virtue of its containing a small amount of radio isotope which obviated the need for the traditional "B-battery" concept also developed by de Forest to supply a high voltage for driving the output stage circuit. While not capable of powering a concert hall audio speaker system, it did make possible use of a small speaker as a nearby personal listening device rather than requiring headphones or earbuds. Without divulging the most critical and closely-held details of the Crystron as the U.S. Patent Office...

Electrons and Magnetic Fields

Electrons and Magnetic Fields, November 1968 Radio-Electronics - RF CafeUniversity of Southampton, England, professor James Holbrook suggests in this 1968 Radio-Electronics magazine article an "easy-to-follow substitute for the left- and right-hand rules," but I'm not so sure that the good professor's "Electron Orbit Method" is any better or easier to remember. Admittedly, it is hard to remember whether the use a left-hand rule or a right-hand rule for the various physical laws - motor rotation direction, current induction, torque, vector cross products, etc. Those involving current flow are made even more confounding because you need to know whether the creator of the rule refers to conventional current flow (positive-to-negative) of electron current flow (negative-to-positive). Note in Figure 110 from the Electricity volume of Basic Navy Training Courses how the generator rule is described as a left-hand rule with conventional current flow...

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...

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 weekday. RF 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. If you need your company news to be seen, RF Cafe is the place to be...

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 weekday. RF 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. If you need your company news to be seen, RF Cafe is the place to be...

Mac's Radio Service Shop: Mac and Free Estimates

Mac's Radio Service Shop: Mac and Free Estimates, January 1950 Radio & Television News - RF CafeI always learn something new with each episode of "Mac's Radio Service Shop," but not necessarily related to electronics. Such is the case in this 1950 issue of Radio & Television News magazine where after Mac gives Barney a quick lesson in how to determine a transformer's winding turns ratio when needing to create an impedance match circuit. He then, while discussing whether 'free' repair estimates are truly free or of any real value at all, he uses the phrase 'a horse on you.' Maybe it is because I don't frequent bars that I had never heard that, but after a little research I now know it refers to a bar dice game called 'Horse.' 'A horse on you' is when you lose the final round of a 2-out-of-3 challenge. 'A horse apiece' is when you and your opponent...

The Future of the Transistor

The Future of the Transistor, July 1952 Radio-Electronics - RF CafeFor many years, Radio-Electronics magazine editor Hugo Gernsback and Audion tube inventor Dr. Lee de Forest had sort of a mutual admiration society thing going on. that's understandable because they we both men of great accomplishment and are deserving of everyone's admiration. In this 1952 issue, Dr. de Forest was invited to procrastinate on future of the transistor - the semiconductor equivalent of his amplifying vacuum tube. He humbly states, "If in the year 1912 some editor had requested of me an article on the 'Future of the Electronic Tube,' I probably would have felt quite as incompetent and short-sighted a prophet of the developments of that [...], as I feel today as Mr. Gernsback requests from me an outlook over the future of the transistor, [the] possible successor of the grid tube." Less than four yeas had passed since the Bell Labs trio announced their transistor invention, but the technology advanced quickly once made known. History shows Dr. de Forest was correct in predicting the vacuum tube and transistor (in all their various forms) would coexist for a long time. It was not until the 1980s that solid state devices had replaced nearly all tubes (except the CRT display)...For many years, Radio-Electronics magazine editor Hugo Gernsback and Audion tube inventor Dr. Lee de Forest had sort of a mutual admiration society thing going on. that's understandable because they we both men of great accomplishment and are deserving of everyone's admiration...

IEEE's 2018 "The Art of Failure Analysis"

IEEE's 2018 "The Art of Failure Analysis" - RF CafeSince 2008, IEEE's International Symposium on the Physical and Failure Analysis of Integrated Circuits (IFPA) has on occasion held an "Art of Failure Analysis" photo contest. Familiar shapes and patterns occur regularly in nature at the macro level that can be seen and recognized by almost anyone; e.g., the Nautilus spiral, the Fibonacci series in plant life, and fractal structures. It takes a high power optical microscope or even a scanning electron microscope (SEM) to see those sights in the realm of the very small. Sometimes, though, the images are downright bazaar and look eerily familiar...

The Radio Alarm

The Radio Alarm - RF Cafe

Hugo Gernsback, as I have often pointed out, had a penchant for predicting technology development and user trends. Decades of researching and publishing articles and books, inventing electrical and mechanical devices, and creating educational material enabled a synergistic combination of real-world experience and visionary thinking. In this 1945 Radio-Craft magazine editorial entitled, "The Radio Alarm," Mr. Gernsback envisioned a form of public emergency broadcast system that would notify the public of impending and/or in-process dangers like natural and man-caused disasters, invading armed forces, police alerts, etc. His idea involved incorporating a special always-on circuit into radios that would listen for a broadcast tone and then switch the radio on automatically. Of course in 1945 there would need to be a minute of two allotted for the tubes to warm up before sending out the actual message. In 1951 the CONELRAD system was put into operation to alert citizens in the even of a Cold War era invasion or attack, doing exactly what Gernsback had envisioned, albeit without a the special turn-on circuit. Then, in 1963 the more familiar Emergency Broadcast System (EBS) took over...

RF & Electronics Symbols for Office™

RF & Electronics Schematic & Block Diagram Symbols for Office™ r2 - RF CafeIt was a lot of work, but I finally finished a version of the "RF & Electronics Schematic & Block Diagram Symbols"" that works well with Microsoft Office™ programs Word™, Excel™, and Power Point™. This is an equivalent of the extensive set of amplifier, mixer, filter, switch, connector, waveguide, digital, analog, antenna, and other commonly used symbols for system block diagrams and schematics created for Visio™. Each of the 1,000+ symbols was exported individually from Visio in the EMF file format, then imported into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or down without becoming pixelated, so all the shapes can be resized in a document and still look good. The imported symbols can also be UnGrouped into their original constituent parts for editing...

Electromagnetism - Basic Navy Training Courses, NAVPERS 10622

Electricity - Basic Navy Training Courses, NAVPERS 10622, Chapter 12 - Electromagnetism - RF CafeAfter previously presenting the permanent magnet, chapter 12 of  the NAVPERS series of courses takes a look at the electromagnet. It is like a natural or artificial magnet in its attraction but unlike in its control. Its attraction is tremendous-it can hold tons of iron. But because this magnet is powered by an electric current, the magnetism can be turned on and off with the flick of a switch. Electrically-powered magnets are called electromagnets. Electromagnets come in all sizes and shapes - and do all kinds of jobs. All electromagnets use a coil of wire and a core of iron to produce their magnetism. The coil furnishes the magnetic flux and the iron concentrates it. To understand how it works, you should start with the magnetic field around a conductor. All conductors carrying current are surrounded by a field-of flux. As in the case of artificial magnets, iron filings will make this field visible. Connect a wire to a battery and dip the wire in iron filings...

Innovative Power Products (IPP) Baluns & Transformers
Windfreak Technologies Frequency Synthesizers - RF Cafe

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