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Homepage Archive - July 2022 (page 3)

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

Thursday the 21st

Transistor Replacement Problems

For the Record: Transistor Replacement Problems, February 1966 Electronics World - RF CafeBy 1966 the dominance of vacuum tubes, particularly in new products, as stated by Electronics World magazine editor William Stocklin, "...is gradually passing behind us." The Transistor Replacement Problems highlighted in this article refer primarily to finding second (or third or more) sources for transistor types already designed into existing products as semiconductor manufacturers move on to new and better (often much better) devices. There was little motivation for companies to dedicate scare resources to making low volumes of legacy devices just to service radios, televisions, phonographs, etc., which, to be honest, they probably preferred owners would abandon after breaking down and replace them with a newer model. Of course that mentality was nothing new since all manufacturers prefer a throw-away mindset since it serves two primary objectives: selling new products and disposing of products already in the field so as to not have to service them. Mr. Stocklin worried that the situation could get even more serious once integrated circuits entered widespread service...

1st-Ever Solid-State Optical Nanomotor

1st-Ever Solid-State Optical Nanomotor - RF Cafe"Motors are ubiquitous in our everyday lives - from cars to washing machines, even if we rarely notice them. A futuristic scientific field is working on the development tiny motors that could power a network of nanomachines and replace some of the power sources we currently use in electronic devices. Researchers from the Cockrell School of Engineering at The University of Texas at Austin created the first ever solid-state optical nanomotor. All previous iterations of these light-driven motors reside in a solution of some sort, which limited their potential for the majority of real-world applications. This new research was published recently in the journal ACS Nano. The scientists envision using these motors to power a wide variety of things. They could be useful for air quality measurement, as the spinning motion could pick up dust and other particles..."

How to Decide Where to File Patent Applications

How to Decide Where to File Patent Applications - RF CafeIf you are considering filing for a patent, then you might benefit from this short article by Damien Howard and Vlad Teplitskiy entitled, "How to Decide Where to File Patent Applications." Some people believe if you are granted a patent in your home country that protection conveys worldwide, but that is not the case. Says the authors: "Realistically, you can't protect your invention everywhere. How do you decide where to obtain patent protection for your invention? Imagine that you have developed a groundbreaking electronic product. Your product is going to revolutionize the industry and take the world by storm. You don't want your competitors to copy the product, compete with you, or undercut the price. At the very least, you want them to pay you compensation for making their competing product. You know that if you want to protect the product, you should file a patent application. So, you hire a patent lawyer and file a U.S. patent application. Problem solved, right?..."

VIP's Are Hams Too!

VIP's Are Hams Too!, March 1958 Popular Electronics - RF CafeWhat do General Curtis LeMay, Arthur Godfrey, Herbert Hoover, Arthur Collins all have in common? They were Ham radio operators. A lot of famous people were/are Hams, with these and a few other notables mentioned in this March 1958 edition of Popular Electronics magazine. Conspicuously missing is one of modern day's most renowned Hams, and that's Walter Cronkite, KB2GSD (died in 2009). His broadcast career stretched back to World War II, so he was definitely around long enough. Maybe the author just didn't know; after all, he couldn't just look it up on the Internet or in an FCC computer database. By now you probably know that actor Tim Allen, star of the Home Improvement and Last Man Standing television shows, holds a amateur radio license. His character, Mike Baxter, on Last Man Standing, had call sign faux KA0XTT. Tim Allen's (full name Timothy Allen Dick) call sign is KK6OTD...

Electronics Against Cancer

Electronics Against Cancer, August 1959 Popular Electronics - RF CafeThe medical x-ray machine shown here reminds me of the "Illudium Q-36 Explosive Space Modulator" contraption Marvin the Martian wanted to use in "Hare-Way to the Stars" to disintegrate the Earth (because it blocks his view of Venus). Of course our hero Bugs Bunny thwarts his plan, whereupon Marvin asks, "Where's the kaboom?" Can you imagine being fraught with cancer and getting strapped into a chair with that huge hypodermic-needle-looking thingy pointed at you, as shown in this 1959 issue of Popular Electronics magazine? The Caduceus sword in the pic doesn't help matters, either. The trauma of such an experience might have been worse than the treatment for some people. As usual the pioneers took the arrows so that we can benefit from the treatments enjoyed today, and the equipment does not look nearly as intimidating. See also "After Class: X-Rays" for more info...

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 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! 

Wednesday the 20th

My Bifurcated Spinal Cord

My Bifurcated Spinal Cord (Kirt Blattenberger) - RF CafeIn 2012, while moving a heavy safe down some stairs (using a hand truck), something snapped in my lower back that resulted in debilitating leg pain for a month. Hydrocodone was required to enable normal locomotion around the house, and I couldn't lift anything. After about three months, things returned to normal, with occasional relapses. Since that time, I have tried to be careful to not overexert myself, and kept up a regular regime of isometric and low weight, low impact exercise. Maintaining muscle tone is essential for keeping the skeleton in proper alignment. As time went on, I became a little bolder in terms of lifting, pushing, and pulling heavy objects, and got away with it until early March of this year when I foolishly used a long pry bar to tip over a huge tree stump. The stump finally broke loose, and so did my back. This time, the pain was so bad that I couldn't walk more than a couple feet without needing to recover, and finding a comfortable position to relieve the hurt was nearly impossible. Even hydrocodone barely touched it. I have always avoided taking any sort of medicine, even ibuprofen or acetaminophen, so at trip to a back surgeon† ensued. An x-ray showed a few bone spurs on some of the vertebrae impinging on my spinal cord, but nothing deemed severe enough to cause the level of pain I was experiencing. My doctor likely thought I was exaggerating, so I requested that he order an MRI...

Anyone Remember Calling WE6-1212 and TI4-1212?

Anyone Remember Calling WE6-1212 and TI4-1212? - RF CafeLong before there was a World Wide Web for getting the latest weather report and the local time for setting your clocks, there were phone numbers set up with recordings of the sought after information. As a kid in the 1960s and 1970s, I called the weather forecast number, WE6-1212 ("WE" for weather), multiple times daily during the winter in hopes of hearing a forecast for snow, and during the summer in hopes of favorable conditions for flying model airplanes and launching Estes rockets. An obsession with time and watches and clocks had me calling the time phone number, TI4-1212 ("TI" for time), so often that my father used to refer to the lady on the recording that updated the time every 10 seconds as my girlfriend. Those two phone numbers, even though it has been many decades since I've called them, will be forever emblazoned on my mind. I lived just south of Annapolis, Maryland, and it never occurred to me that the phone numbers might be something else for people in other parts of the country. It turns out that the same two numbers were reserved in many cities...

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.

Mallory Clutch-Type Potentiometers

Mallory Clutch-Type Potentiometers, February 1947 Radio News - RF CafeWhat drew my attention with this P.R. Mallory & Company advertisement appearing in a 1947 issue of Radio News magazine was not one of the actual electronic components for which they are most noted - potentiometers, capacitors, switches, metal alloys, and of course batteries (later renamed Duracell). Rather what interested me was the huge variety of standard potentiometer and rotary switch extension shafts Mallory manufactured. Unlike modern electronics where pots and switches are typically mounted to the enclosure with wires running to the circuit assembly, many older radios and televisions had all components mounted on a metal chassis with control extensions reaching to front-panel mounted dials and knobs. As an aside, Philip Rogers Mallory began his company manufacturing tungsten wire for lamps...

FCC HF Direction Finding Center Hiring

Telecommunications Specialist FCC HF Direction Finding Center Hiring - RF CafeIf you can abide the reverse-discrimination woke conditions of working for the Federal Government, what appears to be a great job position is open for a Telecommunications Specialist at the FCC's High Frequency Direction Finding Center (HFDF) in Columbia, MD. The HFDFC provides direct support to the public safety community and other federal partners by locating interference sources, and HFDFC ensures public safety and security of the HF radio spectrum by providing assistance and technical expertise to the FCC and its licensees. It also provides interference resolution to FCC licensees and federal government agencies, and supports the enforcement and management of the HF Spectrum. Duties are described as: "The incumbent performs 'watch duty' and serves as a technical authority providing technical assistance and guidance to communication systems users to resolve radio interference complaints and problems; and collects radio signal analysis information..."

New Parasitic Beam Antenna Design

New Parasitic Beam Antenna Design, January 1947 Radio News - RF CafeSomething about the moniker "plumber's delight" for homebuilt antennas always appealed to me. In the early days of radio it referred to antennas built with threaded galvanized or soldered copper plumbing pipe or threaded black gas pipe. Today, it also includes structures that incorporate sections of cemented PVC pipe (with wire elements strung along or within them). A major issue with using threaded pipe is the potential for passive intermodulation products (PIMs) being generated at the dissimilar metal junctions (various degrees of oxidized metals). With as spectrally "dirty" as many transmitters as there were in the day, PIMs probably paled in comparison to what was spewed as a matter of course. The presence of PIM products, unless severe, is not usually noticeable in CW or phone operations, but with digital communications (very common in modern Ham radio), the bit error rate (BER) can be profoundly impacted by them...

Modelithics New Product Blast July 2022

Modelithics New Product Blast July 2022 - RF CafeModelithics has just published their New Product Blast for July 2022. Modelithics, Inc. is the industry leader specializing in RF, microwave and millimeter-wave measurements and measurement-based modeling of RF and microwave components and semiconductor devices. Software products include libraries of high-accuracy passive and active component models. Product offerings include the Modelithics Complete Library ,Modelithics Complete+3D Library , mmWave & 5G Library, and System Components Library™. This promo features Modelithics Global Models for Amotech capacitors, Modelithics COMPLETE Library non-linear models for two Infineon Schottky diodes and for Smiths Interconnect's resistor series, and New models for multiple Kyocera-AVX and Kemet capacitors...

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

/jobs.htm" target="_top"> 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 /jobs.htm" target="_top">job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge. 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...

Thanks to Anritsu for Their Support!

Anritsu (electronics test equipment)Anritsu has been a global provider of innovative communications test and measurement solutions for more than 120 years. Anritsu manufactures a full line of innovative components and accessories for RF and Microwave Test and Measurement Equipment including attenuators & terminations; coaxial cables, connectors & adapters; o-scopes; power meters & sensors; signal generators; antenna, signal, spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth & WLAN testers; PIM testers; amplifiers; power dividers; antennas.

Tuesday the 19th

Microwave Evolution

Microwave Evolution, March 1952 Radio-Electronics - RF CafeHugo Gernsback, publisher of Radio-Electronics magazine (and others), made the following prediction in a 1952 issue, "Microwaves for industry and commerce are bound to expand enormously in the foreseeable future." That might seem a little obvious at this point, but as with nearly all emerging technologies, there were a lot of naysayers who believed the relatively limited range and high infrastructure cost of microwave communication relay systems would prevent it from being widely adopted for anything other than specialty applications (i.e., those with large budgets like defense and research). Fortunately, enthusiasts persisted and the microwave industry blossomed, just as was the case when cellular telephone system infrastructure started in the 1990's. If you are interested in the history of wireless communications, this piece will be an interesting read.

"Magic" Number of Neutrons Changes Element's Magnetic Field

"Magic" Number of Neutrons Changes Element's Magnetic Field - RF Cafe"A curious thing happened when MIT researchers Adam Vernon and Ronald Garcia Ruiz, along an international team of scientists, recently performed an experiment in which a sensitive laser spectroscopy technique was used to measure how the nuclear electromagnetic properties of indium isotopes evolve when an extreme number of neutrons are added to the nucleus. These nuclei do not exist in nature, and once created, their lifetimes can be as short as a fraction of a second, so the team artificially created the nuclei using a particle accelerator at the CERN research facility in Switzerland. By using a combination of multiple lasers and an ion trap, the team isolated the isotopes of interest and performed precision measurements of atoms containing these exotic nuclei. In turn, it allowed the extraction of their nuclear properties. When measuring a nucleus with a certain "magic" number of neutrons - 82 - the magnetic field of the nucleus exhibited a drastic change, and the properties of these very complex nuclei appear to be governed by just one of the protons of the nucleus..."

Carl Kohler's Life & Times per Son, Christoverre 

Carl Kohler's Life & Times per Son, Christoverre - RF CafeAs mentioned in the past, one of the many great aspects of the Internet, and in particular having a website with its contents easily found on a search engine, is occasionally being contacted by people mentioned in one of the vintage magazine articles I have posted on RFCafe.com and AirplanesAndRockets.com, and/or by people related to someone mentioned. Readers of Popular Electronics magazine in the 1950's through 1970's (including me) looked forward to Carl Kohler's many humorous electronics-related stories and illustrations a few times each year. Carl's leading man was one of print media's first DIYers, and his wife suffered his often less than successful escapades in a sporting manner. A few days ago, none other than Christoverre Kohler, Mr. and Mrs. Carl and Sylvia Kohler's number two son (of four), contacted me to provide some background on his parents. Christoverre happened upon a couple of his father's articles on RF Cafe while doing a search. He was motivated to write in response to the story entitled, "I Married a Superheterodyne!," where I asked whether the Kohlers might have at one time lived in Syracuse, New York. It was due to a mention of General Electric's famous Electronics Park (which is no more). Christoverre set me straight on that matter, and provided some amazing additional information on his parents. His father's talents were not limited...

RCA Advertisement - Transatlantic Morse Code

RCA Advertisement - Transatlantic Morse Code, January 1952 Radio & Television News - RF CafeIf Radio Corporation of America (RCA) was still in existence today, undoubtedly it would be running an advertisement mentioning not just radio and television in their list of wireless communications accomplishments, but also cellphones, satellite navigation (GPS), cable television, and Wi-Fi. Founded in 1919, RCA was bought by General Electric in 1986 and then subsequently broken into components and sold off to other companies like Sony, NBC (National Broadcasting Company), and Comcast. This RCA advertisement heralding Marconi's Morse code message "first forged in 1901 from the mere sound of three dots" appeared in a 1952 issue of Radio & Television News magazine...

Top Electronics Distributors for 2022

Top Electronics Distributors for 2022 - RF CafeSource Today published their list of the Top 50 Electronics Distributors for 2022. As with last year, the date shows May, but it just appeared now in July. Arrow Electronics retained the top position, and Avnet dropped from second to third place. Now in second place is WPG Holdings, which did not appear anywhere in last year's list. According to the company website, "WPG Holdings the largest electronics distributor in Asia and the world, headquarters in Taipei, Taiwan.  WPG is operating through four leading semiconductor components distributors (WPIg, SACg, AITg, and YOSUNg) serves as a franchise partner more than 250 worldwide suppliers." WPG Holdings was founded in 2005, so where was it last year and how did it make such a huge premier appearance on Source Today's list? I thought maybe they had swallowed up some of the other top contenders, but not so. Most of the remaining companies in the list either shifted down by one place because of the WPG Holdings addition, or lost or gained a place or two, but no other real shake-up occurred.

Microwave Klystron Oscillators

Microwave Klystron Oscillators, April 1952 Radio & Television News - RF CafeThe microwave klystron was invented in 1937 by brothers Russell and Sigurd Varian. If you have been in the microwave design business for a couple decades, you undoubtedly recognize the company name of Varian Associates, especially if you worked in the aerospace or defense electronics business. There is a video on YouTube of a segment on Varian done sometime around 1990 by Walter Cronkite. There is also a historical piece on Varian Associates on the Communications & Power Industries website. This circa 1952 article covers the fundamentals of klystron operation and reports on the increasing use of klystrons in high frequency applications - including by amateur radio operators exploring the top end of the bands. Part 2 of this article appeared in the May 1952 issue of Radio & Television News magazine...

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 or so 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. Check them out!

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.

Monday the 18th

Electronics-Themed Comics

Electronics-Themed Comics, November 1957 Radio-Electronics - RF CafeIn 1957, when these communications-themed comics appeared in Radio-Electronics magazine, home-based entertainment electronics was a big deal. Installing a major media setup with a stereo system and/or a television served to prove your technical prowess and hopefully set you up as the neighborhood expert. That fad continued for a few decades, but by now even the most sophisticated equipment is self-configuring and requires little more effort for success than setting it where you want it in the room. Artificial intelligent (AI) uses Bluetooth and WiFi to evaluate the surroundings and adjust accordingly. Your typical Walmart system might not have that capability, but if you're shopping at Walmart for your media gear, you're not really qualifying your setup as high end. These comics do a pretty good job of conveying the mood of the era...

Loudspeaker Repairs Anyone Can Make

Loudspeaker Repairs Anyone Can Make, April 1955 Popular Electronics - RF CafeIn today's throw-away society, most people would never consider attempting to repair a loudspeaker if it were to develop a tear or a puncture. Why should you bother when a replacement is so inexpensive? Well, there are few reasons you might want to affect the repair yourself. First, the speaker might be integrated into the system in such a manner that replacing it would be difficult or even impossible. Second, some speakers are actually pretty darn expensive, especially large diameter models and high quality models regardless of size. Third, a replacement might not be available, as with a vintage radio or television. Fourth, maybe you just want the challenge and satisfaction of repairing the speaker rather than adding its bulk to a landfill. This article from a 1955 issue of Popular Electronics magazine offers a short tutorial on loudspeaker repairs. It was written before foam cones became available, but adapting other repair media and adhesive for foam should not be a big barrier to undertaking such a task. Be sure to choose a glue type that exhibits some flexibility once cured, which means standard cyanoacrylate (CA / superglue) would probably be a poor choice. Special formulations for bonding foam are available and should work well...

Nuclear Attack PSA in NYC

Nuclear Attack PSA in NYC - RF CafeThere are not many of us left who remember the "duck and cover" nuclear attack drills in elementary school back in the 1960's. Now, six decades later, all of a sudden Public Service Announcements (PSA's) are appearing in New York City advising people what to do in the case of a nuclear bomb attack, or in the words of the presenter, "if the big one has hit." I thought it was another Internet spoof, but evidently it is real. Do the people in NYC know something we don't? Our "leaders" appear to be bent on stoking the Russia / Ukraine fire until someone detonates a nuke somewhere. It might even be China against Taiwan - why not while the world is in turmoil? The people in charge are crazy and evil.

ARRL Seeking Public Relations & Outreach Manager

Public Relations & Outreach Manager - RF Cafe"ARRL The National Association for Amateur Radio® is seeking a Public Relations & Outreach Manager for employment at its headquarters in Newington, Connecticut. The manager will be responsible for increasing the awareness and value of the Amateur Radio Service to the public at large, for promoting the value of ARRL and the contributions of its member-volunteers, and for developing outreach opportunities that support awareness and growth of amateur radio. The ideal candidate will be a storyteller who is adept at writing content and developing campaigns to convey ARRL's message to various audiences. This professional must possess the know-how to train and motivate grassroots volunteers, and the ability to develop and sustain long-term relationships with external media. ARRL is also seeking a Social Media Strategist who will be responsible for developing and administering social media content that is aimed at engaging users and creating an interactive relationship with members, the wider amateur radio community, and prospective hams."

Update to CNES Earth-Space Propagation DLL

CNES RF Propagation Calculations DLL - RF Cafe Cool ProductAn update has been provided by Michael M. with more information about the Earth-Space propagation calculation DLL 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. A full list of the functions is given below, including ones for gaseous, cloud and rain attenuation that factors in temperature, precipitation intensity, and atmospheric noise, as well as for inputting geographic location...

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 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.

Sunday the 17th

Ham Radio Theme Crossword Puzzle for July 17th

Ham Radio Theme Crossword Puzzle for July 17th, 2022 - RF CafeThis custom Ham Radio themed Crossword Puzzle for July 17th, 2022, is brought to you by RF Cafe. 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!

Many Thanks to Amplifier Solutions Corporation (ASC) for Continuing Support!

Amplifier Solutions Corporation (ASC) - RF Cafe ASC designs and manufactures hybrid, surface mount flange, open carrier and connectorized amplifiers for low, medium and high power applications using gallium nitride (GaN), gallium arsenide (GaAs) and silicon (Si) transistor technologies. ASC's thick film designs operate in the frequency range of 300 kHz to 6 GHz. ASC offers thin film designs that operate up to 20 GHz.

Friday the 15th

Inventors of Radio - Professor A. E. Dolbear

"Inventors of Radio" Professor A. E. Dolbear, November 1959 Radio-Electronics - RF CafeI have to confess that I do not recall having heard of Professor Amos Emerson Dolbear (aka A.E. Dolbear) prior to seeing this "Inventors of Radio" piece in a 1959 issue of Radio-Electronics magazine. Per the article, "In 1882, just 10 years after Loomis' patent was granted, Prof. Amos E. Dolbear demonstrated what he called an electrostatic telephone before the Society of Telegraph Engineers and Electricians meeting in London, England. This occasion - March 23, 1882 - was probably the first time the human voice was transmitted by radio." Prof. Dolbear was a contemporary of other early electrical communications pioneers like Alexander Graham Bell and Guglielmo Marconi...

Geochron Atlas 2 4K Donated to ARRL

Geochron Atlas 2 4K Donated to ARRL - RF Cafe"Geochron, headquartered in Oregon City, Oregon, has donated a Geochron Atlas 2 4K - a digital Geochron world clock - to ARRL The National Association for Amateur Radio®. Geochron Owner Patrick Bolan arranged the donation for installation at the ARRL Headquarters station, W1AW. The Atlas 2 was reviewed in the February 2022 edition of QST. 'The Geochron Digital Atlas 2 4K displays the Earth with sunrise and sunset rendered in real time,' wrote reviewer Pascal Villeneuve, VA2PV. 'The device is a small computer that plugs directly into any HDM...'"

Watkins-Johnson Tech-Notes

Watkins-Johnson Tech-Notes - RF CafeBelieve it or not, there was a time when the Internet did not exist and getting quality information could be difficult. Perhaps more notably today, bad information is far too easy to get online because there is no qualified peer review of content. Waaaaayyyyyy back in the 1970s and 1980s when I was new to the electronics design world, offices, cubicles, laboratories, company technical libraries, even hallways, were piled high with reference books, magazines, component books, applications notes, datasheets, white papers, and every other form of information that might be useful. Now, of course, the preferred source for information is the Internet, particularly from trusted sources like universities, book publishers, RF Cafe, etc. The problem is that a lot of the old data that was uniquely useful, has not been archived on the Web. Such is the case with an exceptionally useful set of Tech-Notes that appeared in the Watkins Johnson parts catalogs of yore...

Oscilloscopes Evolve from Humble Displays to Powerful Tools

Oscilloscopes Evolve from Humble Displays to Powerful Tools - RF CafeAs someone interested in the history of technology and the evolutionary path taken from initial concept to modern day equipment, this "Oscilloscopes Evolve from Humble Displays to Powerful Tools" article by Alix Paultre on the Electronic Design website is of interest. It begins: "From the early CRT-based tools to the latest multifunctional powerhouses, the venerable oscilloscope has long been a mainstay of electronic design. Able to graphically display a range of electronic circuit performance information as a two-dimensional plot over time, oscilloscopes produce waveforms too fast and transient to be perceived by the human eye alone. Not only is it a primary tool for the electronic design engineer, the oscilloscope also can be found in mil/aero, science, medicine, and telecom, among other spaces. Waveform analysis of properties such as amplitude, frequency, rise time, time interval, distortion..."

RCA Test & Measuring Equipment

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

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 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.

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