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Homepage Archive - October 2022 (page 4)

See Page  1 | 2 | 3 | 4 of the October 2022 homepage archives.

Monday the 31st

Carl and Jerry: The Hand of Selene

Carl and Jerry: The Hand of Selene, November 1960 Popular Electronics - RF CafeThis "The Hand of Selene" Carl and Jerry adventure appeared in the November 1960 issue of Popular Electronics just in time for Halloween. The magazine would have arrived in mailboxes on newsstands sometime in October. With the great popularity of zombies and the undead these days (in which I personally have zero interest), the scheme outlined here to make the hand of Selene (an Egyptian moon goddess) tap out answers to a soothsayer's questions would be a great scheme to use at a Halloween party. Read on to discover the tech savvy teenagers' clever implementation...

Candyflation - Huge Price Increase for Halloween Candy

Huge Price Increase Halloween Candy - RF CafeJust keep repeating, "There is no inflation. We are not in a recession." The Bloomberg report on Halloween candy cost increases this year surely must be wrong, but I reposted some of them here anyway (see thumbnail). I've dubbed it "Candyflation." Reese's candy is up 35% over a year ago. Twix is up 53%. That's nothing; I just paid $118 for a roll of 14-2 Romex wire that cost about $40-$45 two years ago. Gasoline's gone from $2.10/gallon to north of $4/gallon, depending on where you live. Electricity rates here have gone up >10% in two years and Duke Energy wants another 14% or more. Don't blame it on insane levels of deficit spending the last couple years, though. It can't be infrastructure costs and supply shortages needed to accommodate >5M illegal aliens crossing our southern border in the last two years. Of course not. It's that darn Putin causing all the problems, don't you know! We're being devastated here at RF Cafe.

The Spook - Another Weird Effect to Haunt TV

The Spook - Another Weird Effect to Haunt TV, March 1953 Radio & Television News - RF CafeHow often have we all mistaken "spooks" for Barkhausen oscillations? Yeah, it's embarrassing, but we've all done it. I can't tell you how many times as a kid I saw the tell-tale effects on our old black and white TV and said, "Mom, can you remind Dad to do something about those dang Barkhausen oscillations when he gets home from the newspaper office?" If you believe that line of bull hockey, I've got some waterfront property in the Sahara Desert to sell you. The only thing close to "Barkhausen" I might have known back then was the name of a German beer house on Hogan's Heroes (for which I own the entire DVD set). Anyway, this article, written in the days of over-the-air television broadcasts, presents a solution to the annoying "spook" effect caused by poor oscillator circuit shielding...

Thanks to TotalTemp Technologies for Continued Support!

TotalTemp Technologies - RF CafeTotalTemp Technologies has more than 40 years of combined experience providing thermal platforms. Thermal Platforms are available to provide temperatures between -100°C and +200°C for cryogenic cooling, recirculating circulating coolers, temperature chambers and temperature controllers, thermal range safety controllers, space simulation chambers, hybrid benchtop chambers, custom systems and platforms. Manual and automated configurations for laboratory and production environments. Please contact TotalTemp Technologies today to learn how they can help your project.

Wind Farm Dismantled for Coal Mine Expansion

Wind Farm Dismantled for Coal Mine Expansion - RF CafeHaunting the renewable energy extremists this Halloween is the reality of a need for cheap, reliable electricity. The "renewable" adjective is a farce since once a form of energy is converted to another form it cannot be used again - unless you have a >100% Sterling machine. It is a feel-good term for activists. Faced with a freezing citizenry this winter, we learn: "A wind farm in Germany is being dismantled to expand the Garzweiler lignite mine. One of eight turbines installed at the location in 2001 has already been removed. Nevertheless, the German state of North Rhine-Westphalia said it would phase out coal by 2030, as did RWE, the company that owns the mine." Ach du lieber!

Carl & Jerry: Two Detectors

Carl & Jerry: Two Detectors, February 1955 Popular Electronics - RF CafeJust in time for Halloween, John T. Frye's teenage sleuths Carl & Jerry unexpectedly recorded a late-night conversation between two men where they plot how to dispose of the "body" when death occurred as a result of prolonged choking. Employing their trademark technical prowess and scheming ability, the pair sets a trap for the perpetrators and dutifully summon the authorities as they complete their nefarious act of the night before. Halloween comes into play because the recordings were made for use in creating sound effects during the reading of Edgar Allen Poe's "The Pit and the Pendulum" and "The Cask of Amontillado." This story, which appeared in a 1955 issue of Popular Electronics magazine, is a little dark compared to a typical Carl & Jerry story...

RF & Electronics Stencils for Visio

RF & Electronics stencils for Visio r4 - RF CafeWith more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1 scale so that measurements can be made directly using Visio built-in dimensioning objects. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...

Thanks to Copper Mountain Technologies for Continued Support

Copper Mountain TechnologiesCopper Mountain Technologies develops innovative and robust RF test and measurement solutions for engineers all over the world. Copper Mountain's extensive line of unique form factor Vector Network Analyzers include an RF measurement module and a software application which runs on any Windows PC, laptop or tablet, connecting to the measurement hardware via USB interface. The result is a lower cost, faster, more effective test process that fits into the modern workspace in lab, production, field and secure testing environments.

Sunday the 30th

Vintage Radio Themed Crossword for October 30th

Vintage Radio Themed Crossword Puzzle for October 30th, 2022 - RF CafeHere is your custom made Vintage Radio Themed crossword puzzle for October 30th, 2022. Relevant clues have an asterisk (*) by them. 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 or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

Please Visit Triad RF Systems to Thank Them for Their Support

Triad RF SystemsTriad RF Systems designs and manufactures RF power amplifiers and systems. Triad RF Systems comprises three partners (hence "Triad") with over 40 years of accumulated knowledge of what is required to design, manufacture, market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA, bi-directional, and frequency translating amplifiers are available, in formats including tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology partner than a vendor for our line-of-sight communications product line." Please check to see how they can help your project.

Friday the 28th

Tricks of the Trade

Tricks of the Trade, October 1954 Popular Electronics - RF CafeEvery hobby magazine worth the paper its printed on has a "tricks of the trade" type column. Popular Electronics started out its very first issue in October 1954 with a column that went by exactly that name. It contained a very extensive assortment of tips and tricks (aka "kinks"). The images are rather small, but you can get what the inventor had in mind. It's good stuff to know, even in 67 years later in 2022 because just about everything here is applicable in today's electronic projects...

Antenna Quiz

Antenna Quiz, November 1962 Electronics World - RF CafeYou might need to be an antenna aficionado to score well on this Antenna Quiz which appeared in the November 1962 issue of Electronics World magazine. While the antenna configurations are familiar in most cases (after reading the answers' descriptions), some of the names are not (at least not to me). Links to a couple of the ones I wasn't aware of are provided for your benefit. Whenever I see the Beverage antenna mentioned I always envision one of the homebrews (pun intended) when someone soldered together a stack of beer or soda cans to create a ¼-wave vertical or some similar configuration. Of course it was named after the inventor, Harold Beverage. The Zeppelin antenna mentioned here is often referred to as a Zepp. It got its name from the antenna configuration often used on the Zeppelin airships, including on the Hindenburg. Contrary to the belief by some people...

MXene Composite Could Absorb Electromagnetic Interference

MXene Composite Could Absorb Electromagnetic Interference - RF Cafe"A recent discovery by materials science researchers in Drexel University's College of Engineering might one day prevent electronic devices and components from going haywire when they're too close to one another. A special coating that they developed, using a type of two-dimensional material called MXene, has shown to be capable of absorbing and disbursing the electromagnetic fields that are the source of the problem. Buzzing, feedback or static are the noticeable manifestations of electromagnetic interference, a collision of the electromagnetic fields generated by electronics devices. Aside from the sounds, this phenomenon can also diminish the performance of the devices and lead to overheating and malfunctions if left unchecked. While researchers and technologists have progressively reduced this problem with each generation of devices, their strategy thus far has been to encase vital components..."

End-Fed Zepp Antenna for Receiving

End-Fed Zepp for Receiving, November/ December 1941 Radio-Craft - RF CafeAny mention of a "Zeppelin" conjures up thoughts of disaster in the form of the famous Hindenburg incident at Lakehurst, New Jersey, back in 1937. Fortunately, not all things "Zepp" are bad news. The end-fed Zepp (short for Zeppelin) antenna is as popular today as it was when the Germans developed it for use in the Zeppelin airships. One of the major advantages to an end-fed Zepp is that it is, as the name suggests, fed from the end rather than in the center like a dipole. The configuration makes installation simpler than a dipole. Being so simple in construction, the Zepp handily functions as a multi-band harmonic antenna so it is useful on, for instance, the 160, 80, 40, 20, and 10 meter Ham bands. Many companies (e.g., MFJ Enterprises) sell Zepp antennas as well as the modified Zepp known as a J-pole antenna. This article will help you make your own Zepp antenna system, including a matching network...

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 Once Again to everythingRF for Long-Time Support!

everything RF Searchable Database - RF CafePlease take a few moments to visit the everythingRF website to see how they can assist you with your project. everythingRF is a product discovery platform for RF and microwave products and services. They currently have 267,269 products from more than 1397 companies across 314 categories in their database and enable engineers to search for them using their customized parametric search tool. Amplifiers, test equipment, power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers, power supplies, and everything else. Please visit everythingRF today to see how they can help you.

Thursday the 27th

Saga of the Vacuum Tube

Saga of the Vacuum Tube, February 1946 Radio News - RF CafeWhere else other than an original article like this one from a 1945 issue of Radio News magazine are you likely to find such detailed information on the construction of early vacuum tubes? This is Part 21 of the "Saga of the Tube" series. The reference list for information on various tubes is extensive. Having always been interested in the origin of names and designations of components of all sorts, things like learning "...the designation 'EVN' indicates that the tube was intended for use in a receiver (E = Empfanger) as an amplifier (V = Yerstärker ) at low frequencies (N = Niederfrequenz)" is appreciated. You will find many articles on the history of vacuum tubes, beginning with Dr. Lee de Forest's audion, by searching RF Cafe. I found the death notice of author Gerald F. J. Tyne in the April 4, 1981 edition of The New York Times newspaper - headline: "Gerald F. J. Tyne, 81, an Engineer, Researcher and Museum Director..."

Machine Learning's New Math

Machine Learning's New Math - RF Cafe"Recent developments in AI have been astounding, but so are the costs of training neural networks to do their astounding feats. The biggest, such as the language model GPT-3 and the art generator DALL-E 2, take several months to train on a cluster of high-performance GPUs, costing millions of dollars and taking up millions of billions of billions of basic computations. The training capabilities of processing units have been growing rapidly, as much as doubling in the last year. To keep the trend going, researchers are digging down into the most basic building blocks of computation, the way computers represent numbers. 'We got a thousand times improvement [in training performance per chip] over the last 10 years, and a lot of it has been due to number representation,' Bill Dally, chief scientist..."

Anatech Electronics October 2022 Newsletter

Anatech Electronics October 2022 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his October 2022 newsletter that features his short op-ed entitled "It's Getting Crowded in Low Earth Orbit," where he discusses the rapidly increasing number of both operational and non-operational satellites in low earth orbit (LEO). It presents both a physical space crowding problem and an RF spectrum crowding problem. Companies like Anatech help with the RF crowding by designing and building filters to mitigate the presence of nearby signals. Companies like ClearSpace SA (Switzerland) are working the physical space crowding issue by designing and building grappling bot satellites which will grab a satellite (or large debris) and drag it to a lower orbit for atmospheric re-entry. I wonder what the carbon footprint is of a launch vehicle needed to get the bot aloft...

Transistor Topics

Transistor Topics, December 1957 Popular Electronics - RF CafeJohn Bardeen, of Bell Telephone Labs, announced the invention of the transistor 10 years to the month before this article was written in the December 1957 issue Popular Electronics magazine. A decade later, engineers and scientists had revolutionized electronics for commercial, military, and hobby applications. It seems strange to read here about applying transistors at high frequencies, where the definition of "high" is in the hundred of MHz. High power from a transistor was measured in tens of watts. Today they operate into the terahertz realm, and at power in the hundreds of watts. We've come a long way, baby...

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeNew Scheme rotates all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000 website visits each weekday. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 12,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. 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 Wireless Telecom Group for Their Support!

Wireless Telecom Group (RF power and noise measurement) - RF CafeThe Wireless Telecom Group, comprised of Boonton, CommAgility, Holzworth, and Noisecom, is a global designer and manufacturer of advanced RF and microwave components, modules, systems, and instruments. Serving the wireless, telecommunication, satellite, military, aerospace, semiconductor and medical industries, Wireless Telecom Group products enable innovation across a wide range of traditional and emerging wireless technologies. A unique set of high-performance products including peak power meters, signal generators, phase noise analyzers, signal processing modules, 5G and LTE PHY/stack software, noise sources, and programmable noise generators.

Wednesday the 26th

A Tribute to Our Scientists

For the Record - A Tribute to Our Scientists, November 1962 Electronics World - RF CafeThe U.S. Telstar 1 communications satellite launched atop a Thor-Delta rocket on July 10, 1962. It was the first satellite to relay television shows and live broadcasts, telephone calls, and telegraph messages - all analog of course - for both domestic and international purposes. Electronics World magazine editor W.A. Stocklin used his editorial space in the November issue to salute the engineers and scientists that made it possible - which includes all those who paved the way for Telstar I. Planning and development was performed by a consortium of companies and government agencies. Bell Telephone Laboratories built the hardware. AT&T (a spin-off of Bell Telephone Company) actually owned Telstar I. Note that in 1962 the unit prefix "pico" was not in common use, so it mentions micromicrowatts rather than picowatts. Similarly, publications of the era (and before) used micromicrofarads (μμF) rather than picofarads (pF)...

Large Piezomagnetism Appears in Antiferromagnet

Large Piezomagnetism Appears in Antiferromagnet - RF Cafe"Researchers at the University of Tokyo in Japan, Cornell and Johns Hopkins Universities in the U.S. and the University of Birmingham in the UK have observed large piezomagnetism in an antiferromagnetic material,, manganese-tin (Mn3Sn). The finding could allow this material and others like it to be employed in next-generation computer memories. Antiferromagnetic materials are promising candidates for future high-density memory devices for two main reasons. The first is that electron spins (which are used as the bits or data units) in antiferromagnets flip quickly, at frequencies in the terahertz range. These rapid spin flips are possible because spins in antiferromagnets tend to align antiparallel to each other, leading to strong interactions among the spins. This contrasts with conventional ferromagnets, which have parallel electron spins. The second reason is that while antiferromagnets have an internal magnetism created by the spin of their electrons, they have almost no macroscopic magnetization. This means that bits can be packed..."

Cuban Pilot Defects in 1940s Biplane

Cuban Pilot Defects in 1940s Biplane - RF CafeIf you thought the only 1940's-60's era vehicles still serving as mainstream transportation in Cuba were rusting hulks of Chevys and Fords, check out this Antonov An-2 biplane just used by pilot Ruben Martinez to escape the island paradise. This plane could have been on an airport tarmac during the Cuban Missile Crisis. That beautiful radial engine is similar to the ones in the Boeing B-17 Superfortress used in WWII. Maybe Mr. Martinez should have routed his flight to cross into the USA via Mexico, because recently some Cuban refugees arriving via the ocean have been returned, while millions of undocumented, unauthorized aliens are welcomed at the land border. The State Department began allowing travel to Cuba for certain purposes in 2017 in spite of the long-standing atrocious human rights policies.

Radio-Themed Comics

Radio-Themed Comics, January 1958 Radio-Electronics - RF CafeIf you appreciate good humor, then you'll appreciate these electronics-themed comics from the January 1958 edition of Radio-Electronics. Their themes are representative of situations common in the era - like TV repairman woes and men obsessed over electronics gadgets while ignoring their wives. Not that there are rarely ever any comics in today's electronics magazines, but if there were, they likely would poke fun at Oblivion texters and depict fathers being made to look like fools by their disrespectful kids for not knowing how to program a Roku player...

Origins of the 555 Timer - How It Was Named

Origins of the 555 Timer - How It Was Named - RF CafeWho hasn't had some involvement with the iconic 555 timer IC, whether by designing it into a circuit, aligning or troubleshooting a circuit in which it is used, or simply in a classroom or self-study text? I remember many moons ago making a windshield wiper delay circuit for a 1982 Ford Escort, and somehow I wired it in wrong and fried the 555 - it literally blew the plastic case away from over the die! Anywho, this article by Cabe Force Satalic Atwell from Electronic Design does a nice job of delving into the 555 timer's origins - including how it got its name, which I'll bet you didn't know (and neither did I)...

Emergency Radio Truck Covers Detroit Area

Emergency Radio Truck Covers Detroit Area, December 1954 Popular Electronics - RF CafeWith such a good response to the posting of articles from vintage QST magazines, I figured it would be worth investing in some copies of other electronics-related magazines because people old and young enjoy learning about the history of electronics. Popular Electronics was published from October 1954 through April 1985. I remember reading the magazine back in my USAF days (1978-1982). A couple batches of Popular Electronics magazines came up for auction on eBay back in the middle of 2011, and I managed to snag one set that included the December 1954 issue (Vol. 1, No. 3, which was the third edition ever printed). It also included some editions from early 1955 and others stretched into the early 1960s. This is the first installment. Popular Electronics was a hobbyist's magazine, and was chock full articles on small electronics projects, Ham radio, radio-controlled aircraft equipment, audio amplifiers, model train control, basic electronics lessons, and useful charts and tables of data...

Post Your Engineer & Technician Job Openings on RF Cafe for Free

Engineering Job Board - RF CafeRF Cafe's raison d'être is and always has been to provide useful, quality content for engineers, technicians, engineering managers, students, and hobbyists. Part of that mission is offering to post applicable job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge (of course a gratuity will be graciously accepted). 3rd party recruiters and temp agencies are not included so as to assure a high quality of listings. Please read through the easy procedure to benefit from RF Cafe's high quality visitors ...

Many Thanks to LadyBug Technologies for Their Continued Support!

LadyBug Technologies RF Power Sensors - RF CafeLadyBug Technologies was founded in 2004 by two microwave engineers with a passion for quality microwave test instrumentation. Our employees offer many years experience in the design and manufacture of the worlds best vector network analyzers, spectrum analyzers, power meters and associated components. The management team has additional experience in optical power testing, military radar and a variety of programming environments including LabVIEW, VEE and other languages often used in programmatic systems. Extensive experience in a broad spectrum of demanding measurement applications. You can be assured that our Power Sensors are designed, built, tested and calibrated without compromise.

Tuesday the 25th

Bell Telephone Labs - From Atoms to Stars

Bell Telephone Laboratories - From Atoms to Stars, March 1956 Radio-Electronics - RF CafeLots of unfamiliar names of crystal minerals appear in this infomercial by Bell Telephone Laboratories in a 1956 issue of Radio-Electronics magazine. A few such as sodium chloride (aka table salt), arsenic, cuprite, perovskite, spinel, graphite, and beryllium are fairly well known to those of us in the electronics realm, but others like rutile, tridymite, cristobalite, wurtzite, diamond, and niccolite are new to me. Interestingly, rutile "has one of the highest refractive indices at visible wavelengths of any known crystal and also exhibits a particularly large birefringence and high dispersion." I should have known that. Cristobalite has the same composition as quartz but with a different crystal structure. Niccolite, and a couple others contain arsenic. Why are Bell Labs scientists concerned with these and other compounds? By investigating and learning the properties of a wide variety of materials, examples useful to the improvement of their telecommunications infrastructure and end user devices were be discovered. Equally importantly...

Robert Gillespie's Vacuum Tube Collection

Vacuum Tube Collection Robert Gillespie - RF CafeIf you, like me, appreciate the sheer engineering genius and artistry of a vacuum tube - especially the special purpose types - then you'll want to peruse the extensive collection of Mr. Robert Gillespie. His vacuum tube gallery is hosted on the RadioMuseum.org website. He writes: "I started collecting tubes when I was 10, they were like little pieces of artwork. My fascination with tubes took off when I found my first industrial tube in an old warehouse. I do enjoy the odd photocells and photomultipliers, anything built by hand and not by machine. Currently, my focus is on collecting anything pre-1925 from anywhere in the world - which has been greatly boosted as I am now the curator of the Gerald Tyne Collection, author of 'Saga of the Vacuum Tube,' 1977." If you have a unique vacuum tube not already represented there, you are welcome to submit photos and information. There are 1,629 as of this writing.

Loss Figures for 300-Ohm Twin-Lead

Loss Figures for 300-Ohm Twin-Lead, January 1965 Electronics World - RF CafeThe last time I used 300 Ω twin-lead transmission cable for a television antenna is about 20 years ago when I lived in a fairly rural area and had a VHF/UHF aerial mounted on a 20-foot tower with a rotator. Since then the connections have always been 75 Ω coax either to wired cable or a satellite dish (now I have neither). I do, however still have 300 Ω twin-lead running from my ½-wave dipole antenna that is used for FM radio reception. Most people more than 40 years old remember seeing the old twin lead running down across the house roof, down the side, and through the living room wall. My guess is that little consideration was given to cable routing and how it might affect the performance of the cable. Twin-lead cable is amazingly low loss - typically much lower than coaxial cable - when properly suspended. Its weakness is its vulnerability having its impedance altered by nearby structures. Coaxial cable largely solves the proximity problem because in an ideal coaxial cable, all the RF current flows on the outer surface of the center conductor and on the inner surface of the outer shield...

Memristor-Based Reservoir Computing System

Memristor-Based Reservoir Computing System - RF Cafe"Reservoir computing (RC) is an approach for building computer systems inspired by current knowledge of the human brain. Neuromorphic computing architectures based on this approach are comprised of dynamic physical nodes, which combined can process spatiotemporal signals. Researchers at Tsinghua University in China have recently created a new RC system based on memristors, electrical components that regulate the flow of electrical current in a circuit, while also recording the amount of charge that previously flowed through it. This RC system, introduced in a paper published in Nature Electronics, has been found to achieve remarkable results, both in terms of performance and efficiency. "The basic architecture of our memristor RC system comes from our earlier work published in Nature Communications, where we validated the feasibility of building analog reservoir layer with dynamic memristors..."

FCC Report on CB Radio

FCC Report on CB Radio - Computers for FCC, July 1960 Popular Electronics - RF CafeGeneral Dwight D. (Ike) Eisenhower was president when this article appeared in a 1960 issue of Popular Electronics magazine telling of plans for the Federal Communications Commission (FCC) to receive their first computers. Arguments had to be made to justify the expenditure based on how much money might be saved in completing the department's duties. Citizen Band (CB) radio license applications were being received at a rate of 10,000 per month, which was really beginning to strain the processing efforts when combined with the FCC's other responsibilities. Mention of Ike always reminds me of the Happy Days episode with Fonzie saying, "I like Ike. My bike likes Ike..."

Post Your Engineer & Technician Job Openings on RF Cafe for Free

Engineering Job Board - RF CafeRF Cafe's raison d'être is and always has been to provide useful, quality content for engineers, technicians, engineering managers, students, and hobbyists. Part of that mission is offering to post applicable job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge (of course a gratuity will be graciously accepted). 3rd party recruiters and temp agencies are not included so as to assure a high quality of listings. Please read through the easy procedure to benefit from RF Cafe's high quality visitors ...

Many Thanks to KR Electronics for Long-Time Support!

KR ElectronicsKR Electronics designs and manufactures high quality filters for both the commercial and military markets. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop and individually synthesized filters for special applications - both commercial and military. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. All common connector types and package form factors are available. Please visit their website today to see how they might be of assistance. Products are designed and manufactured in the USA.

Monday the 24th

Goodline Transmission Lines

Goodline Transmission Lines, December 1954 Radio News - RF Cafe"What's in a name?" Juliet famously asked that question of Romeo's family name (Montague). Maybe a world created by a bard of tragedy a name makes no matter, but in the world of product marketing a name can subconsciously invoke a notion of familiarity and trust, cause a brand to be unforgettable, or simply provide a clear understanding of what the product is. In the case of Goodline Transmission Lines, for which this full-page ad appeared in a 1954 issue of Radio & Television News magazine, the "Good" part of Goodline happens to be the name of the company owner, Don Good. However, you can be sure he capitalized on the fortunate surname when branding his transmission lines. In looking at the ad you can tell that Don is quite adept at wordplay - including double entendre - and imagery for hawking his wares...

Modelithics COMPLETE Library v22.5 for Keysight ADS

Modelithics Releases the COMPLETE Library v22.5 for Keysight ADS - RF CafeModelithics is pleased to announce the release of the latest version, v22.5, of the Modelithics COMPLETE Library for use with Keysight Technologies' PathWave Advanced Design System (ADS). New nonlinear models for 7 Qorvo GaAs pHEMT devices are another major aspect of version 22.5. These models are validated to 40 GHz and include advanced features like self-heating and ambient temperature effects. In addition, the release includes a new nonlinear model for the Mini-Circuits TAV2-501+ E-pHEMT transistor. This model is validated to 15 GHz and is both substrate and temperature scalable. Finally, new models are also available for Transcom's TC2381 and TC2384 pHEMT transistors...

Inside the Power Amplifier

Inside the Power Amplifier Part 1, July 1959 Popular Electronics - RF CafeThere are still a lot of vintage vacuum tube-based power amplifiers in service. While this article from the July 1959 edition of Popular Electronics magazine focuses on an audio power amplifier, the principles apply at least into the lower RF frequencies used by amateur radio hobbyists and even commercial broadcast equipment. Fundaments of waveform analysis and amplifier operations are covered. Distortion due to nonlinear characteristics of active components is a prime concern for maintaining linearity at all frequencies and for making certain that harmonics and subharmonics are not being blasted into the ether. Dig the large size classroom demonstration model of the amplifier chassis. Those kinds of props were popular with both military and civilian schools. This is part of a many-month "Inside the..." series of articles written by Joseph Marshall...

CNES RF Propagation Calculations DLL

CNES RF Propagation Calculations DLL - RF Cafe Cool ProductThanks to RF Cafe visitor / contributor Michael M. for letting me know about an update to CNES RF Propagation Calculations DLL download hyperlink. In the four months since posting the information, CNES moved the file. This very handy RF propagation software tool is provided free of charge by the French organization Centre National d'Études Spatiales (CNES, National Centre for Space Studies). The PROPAGATION dynamic link library (DLL) contains functions to compute propagation losses according to ITU-R P. recommendations. Versions are available for both 32- and 64-bit Windows and Linux operating systems, as well as for the C and Visual Basic programming languages. Very conveniently, the DLL functions can be referenced from within an Excel spreadsheet as well...

How to Align Receivers

How to Align Receivers, October 1954 Popular Electronics - RF CafeEven in the year 2022, there are still plenty of receivers around that need to be manually aligned for peak performance. They are not necessarily all older equipment, either. Super sensitive receivers for radars, radio astronomy, and security systems are some examples, especially when a combination of center frequency and bandwidth adjustments are necessary. Of course there are plenty of amateur radio receivers and vintage AM, FM, and shortwave radios around that are still in service by hobbyists and collectors. Most of those people probably already know how to tune their radios, but there are always new enthusiasts just entering into the realm that need a helping hand. This article entitled "How to Align Receivers" appearing in a 1954 issue of Popular Electronics magazine will be a big help to them...

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, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's" design has been ripped off by other people and used on their products, so please be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢ per item - Cafe Press gets the rest of your purchase price. These would make excellent gifts for husbands, wives, kids, significant others, and for handing out at company events or as rewards for excellent service. It's a great way to help support RF Cafe. Thanks...

Please Thank Lotus Communication Systems for Their Support!

Lotus Communication Systems Modular RF/Microwave Components - RF CafeLotus Communication Systems began in 2009, setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex Country, Massachusetts. Lotus is committed to highest quality and innovative products. Each RF/microwave module meets exceedingly high standards of quality, performance and excellent value, and are 100% MADE IN USA. Lotus' RF/microwave products cover frequency band up to 67 GHz. Lotus also offers an COTS shield enclosures for RF/microwave prototyping and production. All products are custom designed. We will find a solution and save your time and cost. Lotus has multiple 4 axis CNC machines and LPKF circuit plotters.

Sunday the 23rd

Electronics Themed Crossword for October 23rd

Electronics Themed Crossword Puzzle for October 23rd, 2022 - RF CafeHere is your custom made Electronics-themed crossword puzzle for October 23rd, 2022. 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 or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

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 ISOTEC for Continued Support!

ISOTEC Corporation - RF CafeSince 1996, ISOTEC has designed, developed and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components and filters for wireless service providers including non-magnetic connectors for quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM RF connectors components such as power dividers and directional couplers. Off-the-shelf and customized products up to 40 GHz and our low-PIM products can meet -160 dBc with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and high-performance. Designs that are cost effective practical and repeatable.

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.

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RF Electronics Shapes, Stencils for Office, Visio by RF Cafe
Werbel Microwave (power dividers, couplers)

Windfreak Technologies Frequency Synthesizers - RF Cafe

Temwell Filters