Search RFC: |                                     
Please support my efforts by advertising!
Serving a Pleasant Blend of Yesterday, Today, and Tomorrow™
Vintage Magazines
Electronics World
Popular Electronics
Radio & TV News
QST | Pop Science
Popular Mechanics
Radio-Craft
Radio-Electronics
Short Wave Craft
Electronics | OFA
Saturday Eve Post
Please Support My Advertisers!

Aegis Power | Centric RF | RFCT
Alliance Test | Empower RF
Isotec | Reactel | SF Circuits

Formulas & Data

Electronics | RF
Mathematics
Mechanics | Physics


About | Sitemap
Homepage Archive

Resources

Articles, Forums, Radar
Magazines, Museum
Radio Service Data
Software, Videos


Artificial Intelligence

Entertainment

Crosswords, Humor Cogitations, Podcast
Quotes, Quizzes

Parts & Services

1000s of Listings

Please support RF  Cafe's GoFundMe campaign! Software: RF Cascade Workbook | Espresso Engineering Workbook
RF Stencils for Visio | RF Symbols for Visio | RF Symbols for Office | Cafe Press


Exodus Advanced Communications Best in Class RF Amplifier SSPAs

Anritsu Test Equipment - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low-priced products, all of which I created.

RF Cascade Workbook for Excel

RF & Electronics Symbols for Visio

RF & Electronics Symbols for Office

RF & Electronics Stencils for Visio

RF Workbench

T-Shirts, Mugs, Cups, Ball Caps, Mouse Pads

These Are Available for Free

Espresso Engineering Workbook™

Smith Chart™ for Excel

Temwell Filters

Homepage Archive - April 2025 (page 1)

See Page 1 | 2 | of the April 2025 homepage archives.

Monday the 14th

R-E Puzzler

R-E Puzzler, June 1967 Radio-Electronics - RF CafeMr. Edmund Braun created a couple dozen of these "R-E Puzzlers" for Radio-Electronics magazine in the 1960s. They are akin to crossword puzzles, except there are no Down clues and words, just Across. As you can see in the matrix, he provides one or two letters for each word, with each supplied letter spanning two words. Number 2 gave me some problem since I don't recall having heard of it. Numbers 13 through 15 could present a challenge to the younger generation, but maybe not. There is no phone app available for this R-E Puzzler; you'll have to work it in your noggin or print it out.

Electronics-Themed Comics

Electronics-Themed Comics, August 1965 Electronics World - RF CafeKick back at the end of work today and enjoy this triad of electronics-themed comics from 1963 and 1965 issues vintage Radio & Television News and Electronics World magazines. Other than an occasional contest to create a caption for a comic drawing, when is the last time you saw a comic in a technical magazine? Where has the humor gone? Is everyone so afraid of offending someone that comics have been banned by lawsuit-fearful editors? You have my invitation to create a good-humored cartoon about me or RF Cafe anytime you wish, and I promise not to sue you. I'll even post it here on the website if you like...

Trillion-Watt Laser Pulse Frozen inSingle Shot

Trillion-Watt Laser Pulse Frozen inSingle Shot - RF Cafe"Researchers at the Tata Institute of Fundamental Research (TIFR), Mumbai, have developed a new method to accurately measure ultrashort, ultrahigh-power laser pulses. Their findings were published in Optica, a leading open-access journal in the field of optics. What's the breakthrough? Lasers are one of the most remarkable technologies of the modern age. They can produce pulses of light that last for incredibly short durations, among the shortest ever created by humans. Even more impressively, these brief flashes can carry immense amounts of energy, resulting in peak power levels that far exceed the total electrical power consumption of the entire world, by orders of magnitude..."

These Are the Fantastic Secret Weapons of Germany

Speaking of Pictures... These Are the Fantastic Secret Weapons of Germany, September 10, 1945 Life - RF CafeWithout a doubt, Germany has in the past far overestimated its ability to conquer the world by leveraging its undeniable history of innovation and determination. A success in the Franco-Prussian War gave it a sense of superiority and invincibility. WWI and WWII were lost primarily due to the blitzkrieg strategy later failing to overwhelm and subdue the enemy in short order, causing protracted wars and diminishing resources from within its domain. If Germany had instead exploited its technical prowess in world markets, it might have been an economic superpower today. The native population was/is brilliant. Today, Germany's leaders are, in acts of self-flagellation and penance...

William Dublier, Radio Pioneer, Dies

William Dublier, Radio Pioneer, Dies, October 1969 Radio-Electronics - RF CafeCornell-Dubilier Electric Corporation has been manufacturing capacitors for more than a century - 109 years as of this writing to be more precise. That is utterly amazing, especially since they still use the name of the company founder, William Dubilier. In 1933, they merged with Cornell Radio to form Cornell-Dubilier Electronics. If you have been in the electronics field for a while, you no doubt have heard of their capacitors. In fact, William Dubilier was the inventor of mica-based capacitors. According to this obituary in a 1969 issue of Radio-Electronics magazine (he died on July 25th), Mr. Dubilier held 600 patents. I found a newspaper obit that claims that Dublilier was offered, but did not accept, a knighthood and pension for life by the British as a reward for inventing a submarine detection...

Tips for Technicians: New Zener Diode

Mallory - Tips for Technicians: New Kind of Zener DiodeZener diodes were first introduced to the commercial marketplace in the early 1950s. They were named after Clarence Zener, who discovered the Zener effect in 1934, which is the basis for the operation of these diodes. As with many semiconductor components, Zeners were still a relative newcomer to the electronics realm in 1964 when this full-page promo appeared in Radio-Electronics magazine. The Mallory Type ZA molded-case zener diode offered excellent voltage regulating characteristics at a practical price point, making it suitable for service work, experimentation, and commercial circuitry. With its comparable electrical properties and reliability record...

Friday the 11th

And/Or ... Nand/Nor" ... Computer Talk

And/Or ... Nand/Nor" ... Computer Talk, September 1966 Radio-Electronics - RF CafeDigital logic has been a fundamental part of electronics circuit classes for many decades - even in the late 1970s when I began training in the USAF. It really wasn't until the 1960s - about the time this "Computer Talk" articles appeared in Radio-Electronics magazine, that terms such as "and," "or," "not," "nand," and "nor" - the language of Boolean logic - became common parlance to the general electronics world. Many circuits implementing the Boolean combinatorial functions were in existence, but people did not generally refer to them by those terms. "Switching circuits," "relay circuits," and "ladder circuits" were the lingo of the pre-digital era. Inputs typically drove diode, triode, or pentode tubes...

Plasmonic Modulators Break Wireless Terahertz Barrier

Plasmonic Modulators Break Wireless Terahertz Barrier - RF Cafe"Modern telecommunications infrastructure relies on a broad range of technologies. But ironically, some of these technologies can't readily communicate with each other. The electrical signals used for wireless communications, for example, can't just be shoved into the fiber-optic infrastructure that forms the backbone of modern networks. Instead, they must be first converted to light (and then back again). This important task is performed by a network component called an electro-optic (EO) modulator. 'All information that you have is in the electrical world, but once it leaves your house, it goes into fiber..."

Superadio: Discover May Herald New Radio Era

Superadio: Recent Discover May Herald a New Radio Era, April 1947 Radio-Craft - RF CafeWith Radio-Craft magazine editor Hugo Gernsback, you always need to be careful when reading one of his stories in an April. I was a bit suspicious when seeing this "Superadio" title, and reading about it did not assuage my spider senses. It could, however, be completely legit. Turns out, it was real, and based on a story in the December 28, 1946 edition of Nature magazine. In 1946, scientists at Johns Hopkins University accidentally discovered a new method of radio reception while experimenting with an infrared bolometer. They found that a small strip of Columbium nitride, when cooled to near absolute zero, became superconductive and highly sensitive to radio frequencies...

Engineering & Tech Headlines <Archives>

• Regulatory Slash and Burn at FCC

• Nokia Bell Labs Charts Cellular Future on Space

• Reluctance to Adopt AI Among Business Leaders

• Telecoms Relatively Insulated from Tariff War

• Amazon Satellite Broadband in April

Solid State Electronics - The Spacistor Et Al

Solid State, August 1967 Popular Electronics - RF CafeThe monthly "Solid State" column in Popular Electronics reported on all the wonderful new germanium- and silicon-based devices being prepared for the brave new world of electronics. It is a good resource for historical research. For instance, did you know that the unijunction transistor was originally going be called a "double-base diode?" How about a feeble attempt to integrate solid state and vacuum tubes by incorporating a "semiconductor cold cathode" to replace the standard 6.3 V or 12.6 V heated cathode for supplying an electron source? Have you ever heard of a "spacistor?" A 1957 edition of "Proceedings of the IRE" published a paper by Pucel and Statz titled, "The Spacistor, A New Class of High-Frequency Semiconductor Devices." The summary statement says..."

KR Electronics in Booth 627 at IMS 2025

KR Electronics in Booth 627 at IMS 2025 - RF CafeProviding innovative filter solutions for over 40 years, KR Electronics invites you to visit them in Booth #627 at the 2025 IMS show and talk to our people about your project needs. KR Electronics designs and manufactures high quality filters for both the commercial and military markets, and is ISO 9001:2015 certified. All filter types and individually synthesizes filters for special applications. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. Designed and manufactured in the USA. This year's IEEE MTT-S International Microwave Symposium runs June 16-19, in San Francisco, CA.

Thursday the 10th

What's New: Lasers & Missiles

What's New: Lasers & Missiles, June 1962 Radio-Electronics - RF CafeWhen I first saw the picture accompanying the "Laser Packs a Wallop" news item, I though it was showing ladies' black unmentionables being blown out of a suitcase at an airport luggage check point. That bit, along with a few other "What's New" items appeared in the June 1962 issue of Radio-Electronics magazine. How would you like to have been an astronaut in a rocket with a remote destruct device which was triggered by a specific combination of audible notes sent by a controller? Vibrating reed controllers were commonplace for remote control back in the day. Radio controlled airplanes were commanded by tuned reeds in the airborne receiver that acted as decoders to relay control surface servo movement information. A 2.3 GHz, 25 W amplifier weighing a mere 16 ounces...

Mac's Service Shop: Two for One

Mac's Service Shop: Two for One, March 1960 Electronics World - RF CafeIt is a rare occasion that Barney bests Mac when it comes to electronics prowess. Good natured back and forth often goes on between them during troubleshooting sessions and impromptu discussions about business practices, industry trends, and customer interactions; indeed, John Frye depends on it to make his "Mac's Service Shop" stories, featured in Electronics World magazine, interesting. This time, underling Barney exploits knowledge gained from a recently purchased electronics reference book to trip up shop owner Mac over which of two metals has the lowest resistance. Mac's choice is one many people would instinctively make - and be wrong as Mac was...

Films Conduct Better the Thinner They Get

Films Conduct Better the Thinner They Get - RF Cafe"If you need to move electrons from here to there, you turn to copper. This common element is an excellent conductor and is easily fabricated into wires and circuit board traces. But the situation changes when you get small: really, really small on a nanometer scale. That same copper shows increasing resistance, which means that more of the electrical signal is lost to heat. It could take more energy to power a smaller and denser device, which is just the opposite of what you want for miniature electronics. Researchers at Stanford led by Asir Intisar Khan in Eric Pop's lab have been experimenting with a novel thin film scaled down..."

Radio-Electronics Goes to the World's Fair

Radio-Electronics Goes to the World's Fair, September 1964 Radio-Electronics - RF CafeThe 1964 World's Fair showcased several groundbreaking technological innovations, as reported in the September 1964 issue of Radio-Electronics magazine. Among the highlights were the Picturephone, a precursor to modern video calls, which allowed users to see and hear the person they were talking to in real-time. Another notable exhibit was the Uniscope, a large-screen television system capable of displaying high-resolution images. The fair also featured demonstrations of early computer technology, including IBM's System/360 mainframe computer, which could perform complex calculations and process large...

Basic Digital Logic Course - Part 3

Basic Digital Logic Course, December 1974 Popular Electronics - RF CafeHere is the final installment in the "Basic Digital Electronic Course" series that ran in three issues of Popular Electronics magazine. The first two parts laid the groundwork with an introduction to binary, octal, and hexadecimal arithmetic, Boolean logic, AND, OR and NOT gates, and some truth tables. Armed with those fundamentals, the authors now dive into flip-flops, encoders and decoders, debouncing circuits for switch inputs, integrated circuit (IC) types, and interconnect methods to design and build a simple digital computer with a 7-segment LED display. Don't expect too much from the computer since it was only three years earlier, in 1971, that Intel introduced the world's first integrated microprocessor - the 4-bit model 4004 central processing unit (CPU)...

Wednesday the 9th

Frequency Modulation w/Carrier Suppression

Frequency Modulation Equations Formulas Carrier Suppression Bessel - RF CafeFrequency modulation (FM) uses the instantaneous amplitude of a modulating signal (voice, music, data, etc.) to directly vary the frequency of a carrier signal. Modulation index, β, is used to describe the ratio of maximum frequency deviation of the carrier to the maximum frequency deviation of the modulating signal. The concept was pioneered by Edwin H. Armstrong in the late 1920s and patented in the early 1930s. Depending on the modulation index chosen, the carrier and certain sideband frequencies may actually be suppressed. Zero crossings of the Bessel functions, Jn(β), occur where the corresponding sideband, n, disappears for a given modulation index, β...

Transistor Terminology

Transistor Terminology, August 1957 Radio & TV News - RF CafeMany years have passed since I sat in a college classroom to learn about transistor fundamentals. The industry had long moved past germanium transistors and was solidly into silicon. Having been formally introduced to transistors in the USAF, I was familiar with their functionality from a technician's perspective of checking for gain, proper bias (as indicated on "educated" schematics), and determining go-no-go health by performing a front-to-back resistance measurement using an ohmmeter. Holes, energy bands, gate widths, and doping levels were first encountered in solid state physics class, however. This article does a nice job of introducing the terms and concepts at a layman's level. I actually found the vacuum tube circuits in our radar unit easier...

Landing That Job Interview

Improve Your Chances of Landing That Job Interview - RF Cafe"One of my close friends is a hiring manager at Google. She recently posted about an open position on her team and was immediately overwhelmed with applications. We're talking about thousands of applicants within days. What surprised me most, however, was the horrendous quality of the average [application] submission. Most applicants were obviously unqualified or had concocted entirely fake profiles. The use of generative AI to automatically fill out (and, in some cases, even submit) applications is harmful to everyone; employers are unable to filter through the noise, and legitimate candidates have a harder time getting noticed - much less advancing to an interview..."

Reverberation and Ambiophony

Reverberation and Ambiophony, October 1964 Radio-Electronics - RF CafeHere is a new word to add to your technical lexicon: Ambiophony, compliments of Mr. Gilbert A. Briggs, in a 1964 issue of Radio-Electronics magazine. The word "ambiophony" comes from the Greek words "amphi," meaning "around" or "on both sides," and "phonos," meaning "sound." Thus, ambiophony refers to a sound reproduction technique that creates an immersive, three-dimensional auditory experience by using speakers placed around the listener, thereby reducing unwanted echo and/or adding reverberation. It explains how the Haas effect influences perceived sound direction and how strategically placed and delayed speakers can create a desired acoustic environment, improving sound intelligibility...

Standing Waves on Transmission Lines

Standing Waves on Transmission Lines, December 1942 QST - RF CafeIn this article from a 1942 issue of QST magazine, author T.A. Gadwa employs a standing wave mechanism analogy that I don't recall having read before - that of a dam on a river. The river is the transmission line with a lake as the source (presumably) and then he imagines a dam load. The dam standing waves, per his description, have phase and amplitude characteristics that depend on how tall the dam wall is relative to the surface height of the dammed river. An extensive array of graphs is provided showing how the current of the dam standing waves react to the dam transmission line termination impedance. I always wonder when seeing electrical-mechanical parity examples whether, as with this case, there are any dam magazine articles out there that use an electrical transmission line to help fellow civil engineers...

Please Thank IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products has been designing and manufacturing RF and Microwave passive components since 2005. We use the latest design tools available to build our baluns, 90-degree couplers, directional couplers, combiners/dividers, single-ended transformers, resistors, terminations, and custom products. Applications in military, medical, industrial, and commercial markets are serviced around the world. Products listed on the website link to detailed mechanical drawings, electrical specifications, and performance data. If you cannot find a product that meets your requirements on our website, contact us to speak with one of our experienced design engineers about your project.

Tuesday the 8th

Here Comes the Laser

"Here Comes the Laser, January 1963 Radio-Electronics - RF Cafe In our present day where lasers of many wavelengths and powers in the megawatts are considered routine, this 1963 article from Radio-Electronics magazine shows how far the technology has come in the more than six intervening decades. Optical masers (i.e., lasers) in the field of radio and electronics technology are explored. Lasers generate coherent light beams and have a wide range of applications, from handling millions of telephone calls and TV channels to powering satellites and spacecraft. The article discusses crystal and gaseous lasers, their components, and how they function...

Quantum Networking: Scalable Entanglement

Quantum Networking: Achieving Scalable Entanglement - RF Cafe"Quantum networks - where entanglement is distributed across distant nodes - promise to revolutionize quantum computing, communication, and sensing. However, a major bottleneck has been scalability, as the entanglement rate in most existing systems is limited by a network design of a single qubit per node. A new study, led by Prof. A. Faraon at Caltech and conducted by A. Ruskuc et al., presents a groundbreaking solution: multiplexed entanglement using multiple emitters in quantum network nodes. By harnessing rare-earth ions coupled to nanophotonic cavities..."

Engineering the Integrated Communications System

Engineering the Integrated Communications System, December 1950 Radio & Television News - RF CafeAs a follow-on to the "Planning Integrated Signal Communications" story, this article is the next step in the U.S. Army Signal Corps' implementation of ubiquitous communications systems. Along with powerful transmitters and super-sensitive receivers at command communications hubs are the many hand-held, back-pack, and vehicular radios needed to complete strategic and tactical operations across the face of the Earth. It wasn't just wireless systems that Signal Corps engineers and technicians were responsible for, but also all the wired equipment and interconnecting cabling. The possibility of software configuration for network switches, radios, modems, telephones, antennas, and ancillary components had never been thought of in 1950 (by very few, anyway). Everything was set up with patch panels...

Putting the Helix Antenna to Work

Putting the Helix Antenna to Work, November 1958 Radio News - RF CafeAuthor William Blair lamented in a 1958 issue of Radio & TV News magazine that helix (aka helical) antennas had not yet been widely adopted by amateur radio operators despite the advantages they can provide. Helix antennas are used for transmitting and receiving circularly polarized electromagnetic waves. An advantage of using a circularly polarized antenna for receiving is that it is able to make use of wavefronts arriving at any polarization angle along the propagation axis, thereby accommodating transmissions at any polarization angle. Theoretically, an ideal antenna with a particular polarization would not receive a signal arriving at an angle perpendicular to it, and the strength of any signal would be proportional to the cosine of the angle of impingement...

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. 

Monday the 7th

Televising the Moon

Televising the Moon, October 1964 Radio-Electronics - RF CafeIn this October 1964 issue of Radio-Electronics magazine, editor Hugo Gernsback writes about the historic feat on July 31 of that year, where NASA lunar probe Ranger 7's RCA-designed television cameras successfully transmitted the first close-up televised pictures of the moon's surface to Earth after six previous failed attempts. The unmanned spacecraft traveled 240,000 miles through space over 68 hours to capture 4,316 still images with its six high-resolution cameras. These images provided crucial information for future manned lunar explorations, revealing that the dust layer on the moon's surface is likely only 2 to 12 inches deep, and showing small craters down to sizes of three feet. The success of Ranger 7 marked a significant advancement in lunar exploration technology, paving the way for further unmanned missions and eventual manned expeditions to the moon...

54% of Hyperscale Data Centers in U.S.

54% of Hyperscale Data Centers in U.S. - RF cafe"New data from Synergy Research Group shows that the number of large data centers operated by hyperscale providers increased to 1,136 at the end of 2024, having doubled over the last five years. Meanwhile it has taken less than four years for the total capacity of operational hyperscale data centers to double, as the average capacity of newly opened facilities continues to climb. Synergy's data shows that the United States still accounts for well over half of total worldwide capacity, measured by MW of critical IT load, with Europe and China each accounting for about a third..."

Printed Circuits for Everyone

Printed Circuits for Everyone, April 1964 Radio-Electronics - RF CafeThis 1964 Radio-Electronics magazine article provided a 12-step guide for creating printed circuits at home, which involves gathering necessary materials, designing the circuit layout, applying resist materials, etching the board, and attaching components. The process could be laborious and often did not produce satisfactory results (ask me how I know). However, modern methods have significantly improved and streamlined this process, making it more efficient and accessible. Today, low-cost prototypes can be easily obtained from various online sources, allowing hobbyists and professionals alike to create high-quality printed circuit boards without the need for extensive manual labor or specialized equipment. These advancements have revolutionized the way we...

B & K Precision 1440 Oscilloscope

B & K Precision 1440 General Purpose Oscilloscope, January 1972 Popular Electronics - RF CafeToday, if Rohde & Schwarz, Keysight, or some other major test equipment manufacturer announced during a trade show presentation a new oscilloscope model with a "Breakthrough!" featured dubbed "Cali-Brain®," they would be laughed off the stage. The technology truly was a breakthrough in terms of displaying peak-to-peak waveform measurements in a numerical presentation along with a cursor line indicating the pk-pk extent from the display. It was not as convenient as next-generation scopes that provided a movable horizontal pair of lines with a direct digital voltage difference readout, but it did take some of the guesswork and potential error out of readings on complicated waveforms. Of course modern microprocessor-based measurements...

Many Thanks to Transcat | Axiom Rental Equipment for Continued Support!

Transcat | Axiom Rental Equipment - RF CafeTranscat | Axiom Rental Equipment allows you to rent or buy test equipment, repair test equipment, or sell or trade test equipment. They are committed to providing superior customer service and high quality electronic test equipment. Transcat | Axiom offers customers several practical, efficient, and cost effective solutions for their projects' TE needs and is committed to providing superior customer service and high quality electronic test equipment. For anyone seeking a way to offload surplus or obsolete equipment, they offer a trade-in program or they will buy the equipment from you. Some vintage items are available fully calibrated. Please check out Transcat | Axiom Rental Equipment today - and don't miss the blog articles!

Friday the 4th

United Aircraft Corporation

United Aircraft Corporation, April 29, 1950 The Saturday Evening Post - RF CafeIf you do a lot of overseas air travel for work (or any other reason), this en route time map from a 1950 issue of The Saturday Evening Post magazine might give you a bit of cheering up. Compare the length of time in the air back during the day of propeller-driven airliners versus what you typically experience today. United Aircraft published that a trip from New York to London took 12-½ hours (with favorable winds). The same flight today takes around 7-½ hours, a 40% reduction. From Seattle to Tokyo was 28-½ hours, and is now 10-½ hours, for a 63% reduction! Those shorter flight times are due to both faster jet-powered airplanes and an ability to climb to and cruise at altitudes where jet stream winds are highly additive. Of course having to endure 10-½ hours crammed into a narrow seat with the back of the front...

QeC1001®©™ Quantum Entanglement Microprocessor

QeC1001®©™ Quantum Entanglement Microprocessor, courtesy QentComm®©™ - RF CafeIn a jaw-dropping leap that could rewrite the rules of technology, QentComm®©™ (Quantum Entanglement Communications), a Greensboro-based visionary force, has unveiled the QeC1001®©™, an 8-qubit quantum entanglement processor microchip forged entirely from carbon nanotubes (CNTs) - a brainchild of Kirt Blattenberger, the company's progenitor and chief architect. Announced on qentcomm.com, this marvel sips a scant 5 milliwatts, staking its claim as the most energy-efficient communication technology ever conceived, thanks to a proprietary "quantum carbon nanotube lattice" that shuns traditional electromagnetic (EM) waves for quantum entanglement - what Albert Einstein dubbed, "spooky action at a distance." Clocked at a nostalgic tens of kilohertz - evoking 1960s transistor vibes - the QeC1001®©™ delivers computational bravado that leaves modern power-hogs in the dust, powering every QentPhone®©™...

TV DX

TV DX, November 1957 Radio-Electronics - RF CafeI know a guy, a multi-decade-long Amateur Radio operator, who at one time was a big participant in TV DXing. For those who are not familiar with the techno-sport, TV DXing is the hobby of receiving and identifying distant television broadcast signals from far-off locations, often using specialized antennas and receiving equipment. Enthusiasts seek to capture signals from stations hundreds or even thousands of miles away, which requires advanced technical skills and sophisticated reception techniques. Modern-day DX-ers typically document their reception achievements by capturing screenshots, logging station details, and sharing their findings with other hobbyists through...

Engineering & Tech Headlines <Archives>

• FCC Toughens Stance on Pirate Radio

• Mobile Operators Bemoan $109B Infrastructure Cost

• 5G Adoption Grows, LTE Remains Strong

• China to Host World Radio Conference?

• Intel Delays Ohio Fab Till 2030

Television Steps Out!

Television Steps Out!, January 1948 Radio-Craft - RF CafeMost of us have heard of the National Association of Broadcasters (NAB). Founded in 1922 at the dawn of commercial radio broadcasting, it is still in existence today. When commercial television broadcasting "stepped out" in a major way in the early 1940s, industry chieftains and station owners decided that their new media paradigm was unique enough to warrant a separate union, so the Television Broadcasters Association (TBA) was formed. A lot of effort went into establishing and building a coalition with enough influence in the marketplace and with government regulators, independent of radio, to exist as a force to be dealt with. Many people believed that radio as an entertainment and news media source would decrease at a rate as great or greater than television was increasing. Once again, experts were not successful at predicting behavior of the citizenry, which was true both in the United States and around the world...

Thanks Again for Windfreak Technologies' Continued Support!

Windfreak TechnologiesWindfreak Technologies designs, manufactures, tests and sells high value USB powered and controlled radio frequency products such as RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters. Since the conception of WFT, we have introduced products that have been purchased by a wide range of customers, from hobbyists to education facilities to government agencies. Worldwide customers include Europe, Australia, and Asia. Please contact Windfreak today to learn how they might help you with your current project.

Thursday the 3rd

New & Timely

New & Timely, December 1969 Radio-Electronics - RF CafeThe December 1969 issue of Radio-Electronics magazine's "New & Timely" column reported that at the National Electronic Association conference, technicians reported burns and eye damage caused by X-radiation from color TV sets under repair. Night vision scopes for commercial use were introduced by Raytheon, suitable for law enforcement, industrial security, and nature study. A joint U.S.-Indian plan planned to beam TV directly to millions of Indian villagers via a stationary applications satellite in 1972. The French Atomic Energy Commission used a superpowerful laser to create minute thermonuclear explosions, fusing deuterium...

Anatech Intros 3 New Filter Models for April 

Anatech Electronics Intros 3 New Filter Models for April 2025 - RF CafeAnatech Electronics offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. Three new filter models have been added to the product line in April, including a 5500 MHz WiFi cavity bandpass filter, a 3437-3537 MHz ceramic duplexer filter, and a 1425 MHz cavity bandpass filter. Custom RF power filter and directional couplers designs can be designed and produced with required connector types when a standard cannot be found, or the requirements are such that a custom approach is necessary...

The Electron Microscope

The Electron Microscope, May 1955 Popular Electronics - RF CafeThis article published in a 1955 issue of Popular Electronics magazine is a really good primer on the history and working principles of the electron microscope. It also explains why such a device is needed; i.e., why an optical microscope cannot do the job when really high levels of magnification are required. As object dimensions are spaced at distances near to or less than the optical wavelength being observed, it becomes impossible to resolve into separate features. Accordingly, when observing at the upper end of the visible light spectrum at around 400 nm, under ideal conditions you would not be able to clearly discern two feature less than about 800 nm apart. Current (2019) CMOS gate thicknesses run about 5 μm, so visible light cannot be used to image those structures. Another resolution limiting factor is aperture size, which, depending on the wavelength causes diffraction patterns of two objects to overlap...

Pacific T.V. Vacuum Tube Supply

Pacific T.V. Vacuum Tube Supply - RF CafeIf you are a seasoned vintage electronics equipment aficionado, restorer, hobbyist, etc., then you most likely already have your own list of supply sources for vacuum tubes. Contrary to what others might think, there is still a healthy stock of tubes available from private websites like Pacific T.V. (hat tip to Bob Davis), as well as collective sites like eBay, Facebook Marketplace, Craigslist, and vintage electronic equipment forums. Prices for common tubes are surprisingly low if you shop around. If you need an output power amplifier for a commercial radio station, be prepared to shell out major wampum, though. Many NOS (new old stock) varieties in original boxes can be had, as well as used tubes. Most have been tested for specification compliance.

Westinghouse Wartime Products

Westinghouse Wartime Products, May 1943 Popular Mechanics - RF CafeWestinghouse is yet another bulwark company of America's foundational industrial age, beginning in the late 19th Century. George Westinghouse founded eponymously-named company, Westinghouse Electric & Manufacturing Company, in 1886, during the time he was working with Nikola Tesla (I wonder whether any of the current-day anti-Tesla nimrods are stupid enough to vandalize NT statues and monuments?) to institute a commercial electrification infrastructure. Mr. Westinghouse began his life of fame and fortune with a locomotive air brake design. During World War II, Westinghouse's many locations designed and manufactured many types of products to facilitate troops in all Theaters of Operation. This 1943 issue of Popular Mechanics magazine carried a full-page...

Wednesday the 2nd

What's Your EQ?

What's Your EQ?, January 1963 Radio-Electronics - RF CafeThis set of three circuit analysis challenges appeared in the January 1963 issue of Radio-Electronics magazine. Readers, staff, and even come companies submitted the "What's Your EQ?" (EQ = Electronics Quotient) content. As an example of the latter, Cleveland Institute of Electronics provided "Draw the Waveform." Don't let the diode vacuum tube deter you from the puzzle. Just mentally replace the tube with a solid state diode symbol with the anode at the top where the tube's plate (anode) is shown. The negative element of a tube is called the cathode, same as the solid state diode. "Capacitor Charge" is easy enough. "Another 2-Box Light"...

2025 UK Engineering Salary Survey

2025 UK Engineering Salary Survey - RF Cafe"Despite increasingly intense competition for skills across all sectors of industry and a growing appetite amongst engineers for a new challenge, engineering salaries appear to have stagnated over the past 12 months. This is just one of the key findings of The Engineer's tenth annual salary survey, which is published in full on The Engineer's website in a new interactive digital format. Attracting responses from 621 engineers working across 12 different sectors, this year's survey was carried out between December 2024 and January 2025. As ever, the results provide a fascinating insight into UK engineering salaries and how engineers are feeling about their careers..."

Television and Sound

Television and Sound, January 1963 Radio-Electronics - RF CafeIn this 1963 issue of Radio-Electronics magazine, editor Hugo Gernsback reflects on the early days of television, noting that the first regular daily TV broadcast began on August 13, 1928, over radio stations WRNY and W2XAL, which were associated with his former publication, Radio News. Initially, these broadcasts were silent, featuring only moving images the size of a postage stamp, and it wasn't until 1931 that TV broadcasts included sound. Gernsback critiques the slow progress in improving the audio quality of television receivers, pointing out that despite advancements in high-fidelity and stereo audio technology, most TV sets still lacked these features due to regulatory restrictions by the FCC. He expresses hope that recent petitions to the FCC...

Exodus AMP20081, 80-1000 MHz, 500 W SSHPA

Exodus AMP20081, 80-1000 MHz, 500 W SSHPA - RF CafeExodus Advanced Communications, is a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide. Exodus' model AMP20081 high power solid state power amplifier (SSHPA) is ideal for broadband EMI-Lab, communications, and EW applications. Class A/AB linear design accommodates all modulations & industry standards. It covers 80-1000 MHz, producing 600 W nominal, with a 500 W P1dB and 56 dB minimum gain. Excellent flatness, optional monitoring parameters for forward/reflected power, VSWR, voltage, current & temperature sensing for superb reliability and ruggedness...

Electronics-Themed Comics

Electronics-Themed October 1944 & May 1945 Radio-Craft - RF CafeIn that these comics from Radio-Craft magazine have an electronics theme, you can claim looking at them is work-related. The themes of the comics reflect common scenarios of the 1944-1945 era in which they were published, but with not much modification can be applied to today's environment. People will always expect more features from products, will be critical of everything presented to them, and will want to haggle for the best deal from the used camel salesman. You might consider using one of them for your next conference or project status presentation. There is a list of many more similar comics at the bottom...

Tuesday the 1st

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-kahm) 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...

 

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page. About RF Cafe.

Homepage Archive Pages

2025:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2024:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2023:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2022:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2021:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2020:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2019:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2018:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2017:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2016:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2015:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2014:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2013:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2012:  1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 (no archives before 2012)

- Christmas-themed items

Temwell Filters
Innovative Power Products (IPP) RF Combiners / Dividers



PCB Directory (Manufacturers)