Homepage Archive - November 2022 (page 4)

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Wednesday the 30th

Electronics-Themed Comics

Electronics-Themed Comics, March 1956 Radio-Electronics - RF CafeThis set of six electronics-themed comics appeared in the March 1956 issue of Radio-Electronics magazine. The one on page 84 is pretty clever, but would need to be modernized in our semiconductor era. I'm not quite getting the page 114 comic. Computer dating is a fairly recent phenomenon - or is it? The page 142 comic suggest otherwise. In fact, I know three married couples who met via an online dating service, all within the last ten years; my daughter is one of them! The shopper in the page 145 comic might have misinterpreted the gist of the signs, but taken literally maybe her assumption isn't so unreasonable. The page 148 comic shows how a "futuristic" concept proposed in the middle of the last century has not only been realized by 2022, but has evolved much farther than imagined...

CMT: Near & Far Field Measurement

Copper Mountain Technologies: Near & Far Field Measurement - RF CafeCopper Mountain Technologies (CMT) has a whitepaper available entitled, "Near and Far Field Measurement." It begins, "To obtain optimal performance in an over the air RF system, the antennas must be chosen to meet specific requirements. Performance parameters such as size, wind-loading, environmental ruggedness, transmission pattern, bandwidth, and power handling capability should be considered. Especially important in an RF system design is the 'link budget.' This parameter determines the end-to-end RF loss and is affected by transmitter output power, feedline loss, transmit antenna gain, path loss through the air, receiver antenna gain, feedline loss once again and receiver noise-figure among other factors. A failure to meet the link budget in an RF system design will result in noisy performance and loss of coverage. In this application note, methods of measuring the transmission (or reception) pattern which determines antenna gain with a VNA will be examined. Most antennas possess some directionality to their performance..."

Pick up Those Profits from Portables

Pick up Those Profits from Portables, June 1951 Radio & Television News - RF CafeRadio & Television News magazine was not normally in the practice of instructing retail outlet salesmen and service shop owners in techniques for hacking their wares, but this article in the June 1951 issue is an exception. In it, A.W. Bernsohn, Managing Director of the National Appliance & Radio Dealers Association, extensively outlines many tried and true schemes for use in convincing customers that they really do need a new, reconditioned, or rental portable radio for those lazy, hazy, crazy days of summer*. Those were the days long before iPods, Walkmans, and smartphones, when "portable" meant maybe smaller than a breadbox, but powered by batteries rather than an AC outlet. If any of the featured models appeal to your sense of nostalgia and you want to lay you hands on one again, try eBay; eventually just about everything shows up there. M. Bensohn even covers the ramification of Regulation "W" of the Federal Reserve Act...

DARPA Cranks Power on Radar Capabilities

DARPA Cranks Power on Radar Capabilities - RF Cafe"DARPA looks to build on previous success in radio frequency power output with new transistor-focused THREADS program. Military and civilian uses for radar range broadly, and the possibilities for radar applications expand almost every day. Whether they are being used to navigate, control air traffic, track weather patterns, carry out search-and-rescue missions, map terrain, or countless other functions, radar technologies are constantly advancing. As radio-frequency (RF) systems, radar capabilities hinge on the ability to sense and communicate across long distances while maintaining signal strength. Powerful RF signal capabilities extend mission-critical communications and situational awareness, but the microelectronic technologies that strengthen RF output - specifically, high power density transistors - must overcome thermal limitations to operate reliably and at significantly higher capacity. Technologies for Heat Removal in Electronics at the Device Scale (THREADS) aims to overcome..."

China Rolls Tanks for "White Paper" Revolution

China Rolls Tanks for "White Paper" Revolution - RF CafeWhen Government controls the media and deploys military and police forces against citizens as a show of force to discourage and suppress protesting against injustice, Government wins and Citizens die. No, I'm not referring to the U.S. In this case China's "Zero Covid" policy resulted in political prisoners burning to death in a quarantined apartment building. The "White Paper Revolution" consists of people symbolically waving blank sheets of paper. Communists cannot abide a challenge to authority, so any measure to end the situation is justified - including murdering human beings. The world's opinion is irrelevant, especially since global economies depend heavily on China. Politicians, university heads, and corporate titans are all sold out to them, therefore will comply as directed. Evidently, though, most people don't mind because Communism is being adopted across the Earth. You've been warned...

Marconi - Father of Radio?

Marconi - Father of Radio?, January 1939 Radio-Craft - RF CafeThis is a must-read article for all persons interested in the history of wireless communications. Seriously. Stop what you are doing and read it. I guarantee the vast majority have never heard of this challenge to the veracity of Mr. Guglielmo Marconi's bestowed title of "father of wireless telegraphy." Most of us are at least passingly familiar with challenges to Samuel Morse's, Thomas Edison's, and a few other notables' claims to being the first at a particular technical breakthrough, but herein, as penned by of Lieutenant-Commander Edward H. Loftin, is a first-hand account of multiple successful challenges by the U.S. Patent Office against Mr. Marconi and his company, Marconi Wireless Telegraph, Ltd., regarding filings for patent protection. As with the other aforementioned individuals, history writers long-ago grew tired of reminding the public of often dubious assertions of creative individuals - other than that it seems every December 17 the media is sure to bring up Whitehead's and Chanute's claims...

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. 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 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.

Tuesday the 29th

Operation of a High-Quality CCTV Camera

Operation of a High-Quality CCTV Camera, December 1965 Electronics World - RF CafeThis "Operation of a High-Quality CCTV Camera" article from a 1965 issue of Electronics World magazine interests me not necessarily because I am interested in CCTV's but because it has many similarities to the video mapper system used in the radar system I worked on in the U.S. Air Force. It was probably built around the same era, so no surprise there. The combination of analog and digital electronics is likely one of the earliest examples of such an integration. The digital portion is for timing, not video processing. An electromagnetically scanned vidicon tube is the heart of the system. Rather than using the television type composite timing/amplitude signals that require complex circuits to deconstruct and direct portions of the signal to appropriate circuits, this is truly digital timing. In fact, the timing diagram show here is one of the earliest I recall seeing in these vintage magazines...

Kolster K20 Receiver Radio Service Data Sheet

Kolster K20, K22, K25, K27 and K37 Six-Tube Receivers Radio Service Data Sheet, October 1930 Radio-Craft - RF CafeHow did we ever accomplish research without the Internet? Sure, that is a rhetorical question, but I find myself asking that often when I find information on something I figured there was no way anything would be available. Such was the case when looking up this Kolster K20 radio. Its Radio Service Data Sheet appeared in the October 1930 edition of Radio-Craft magazine. Mr. Gordon Bell, WA2YQY, provided the photo of the one to the left, which I found on the RadioAtticArchives.com website. As with nearly all radios of the era, is has a nicely styled wooden console cabinet. Note the simplicity of the tuning indicator...

CMT Bootcamp 101 Webinar: Software Tips & Tricks

Copper Mountain Technologies Bootcamp 101 Webinar: Software Tips & Tricks - RF CafeCopper Mountain Technologies (CMT) has a webinar coming up in league with Eravant as part of our VNA 101 Bootcamp Webinar series titled "Software Tips & Tricks." The CMT vector network analyzer software has a lot of features and capabilities. During this session, we will review some aspects of the software in more detail to help users understand how to get the most out of the software. This is a follow-on to the previous "Fixture Requirements to Accurately De-Embed DUTs from VNA Measurements" Webinar. Automatic Fixture Removal software may be used to remove the effects of fixtures from the measurement of a Device Under Test. It's fast and easy to use, but it is imperative to understand the extent to which fixture-related measurement impairments may be compensated. During this webinar, we will review the possible pitfalls during de-embedding and measurement of a DUT on a fixture...

Cold War Era Ad Themes Remain Relevant

Cold War Era Themes Still Relevant - RF CafeWhile not specifically related to RF Cafe type content, this article on the Physics.org website entitled, "Fun Research on Cold War-Era Ads About Flying Saucers, UFOs Finds Themes That Remain Relevant Today," is an interesting bit of sci-fi techno-nostalgia. A study found that although not exactly the same methods and subjects are being used to influence today's consumers, the motus operandi (MO) are basically the same. "While ads with flying saucers and UFOs may use them differently than in the past, desired messages and reactions from those who place the ads have not changed. Emotion and sensation continue to motivate purchases, and advertisers consistently seek to share messages about quality and technology. Plus, the appetite of consumers for big events has never waned..."

Acoustic Resonator Based on Commercial FETs

Acoustic Resonator Based on Commercial FETs - RF Cafe"A key objective of electronics engineering studies focusing on radio communication is the development of increasingly smaller, lighter, and low-power radio components. This could be achieved by integrating all radio components into a single chip, for instance by combining acoustic microelectromechanical systems (MEMS) with complementary metal oxide semiconductors (CMOS). Researchers at Purdue University have recently used this approach to develop an acoustic resonator based on commercially available field effect transistors (FETs), which was presented in a paper published by Nature Electronics. FETs are a class of transistor that control the flow of electrical current in a semiconductor using an electrical field, which are commonly used to amplify signals and are the building blocks for all logic circuits. "This paper is a culmination of years of work involving multiple graduate students and collaborations with semiconductor companies. 'It began with the recognition of a need for high-Q frequency sources embedded in microchips (CMOS) despite the huge barrier to entry for any new materials or processes into CMOS manufacturing...'"

On the Air with the Civil Air Patrol

On the Air with the Civil Air Patrol, March 1957 Popular Electronics - RF CafeBack in the 1970s while taking flying lessons, I used to enjoy watching the Civil Air Patrol run through its exercises at Lee Airport, in Edgewater, Maryland. For some reason, I never bothered to look into joining. I wish I had. A few years later while in Basic Training (BT) for the USAF at Lackland AFB, Texas, there were a couple guys in my squadron who had been long-time members of the CAP and guess what? They only had to spend the first two weeks in BT, just long enough to do all the paperwork processing, take a few of the classroom sessions, get shots, examinations, a head shave, and to have uniforms issued. Then, immediately before leaving for technical school, they got to sew a stripe onto their shirtsleeves as an Airman 1st Class. High school ROTC guys got to do the same thing. I don't know if the Air Force still has that policy; you might want to check it out if you're planning on joining...

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.

Monday the 28th

Glass for Electronics

Glass for Electronics, November 1965 Electronics World - RF CafeThis "Glass for Electronics" article in a 1965 issue of Electronics World magazine provides some really interesting information about the properties of glass which I, for one, either never knew or have forgotten. One such point is that glass is typically defined with a "softening" temperature rather than a melting temperature. That is because the final characteristics of the glass is highly dependent on the cooling down time/temperature profile. Those of us having been in the world of automated printed circuit assembly (PCA) solder oven operation are familiar with the criticality of time/temperature profiles, so the concept is not new. In the case of PCA's, profiling is necessary to accommodate the often widely varying thermal dimension changes over temperature to prevent fracturing. With glass, it is the final atomic alignment (or misalignment) that is dependent on the cooling process, akin to tempering of metal (although the metal is not heated to the point of liquidus flow). At the time of this article, Corning Glass Works claimed to have >100k unique formulas for glass using various mixes of elements...

Ukraine Power Grid Before After Bombing

Ukraine Power Grid Before After Bombing - RF CafeThese before and after satellite photos of Ukraine's nighttime lighting shows the profound effect of a barrage of power grid infrastructure attacks by Russia's military. While billions of American dollars and state-of-the-art technology are funneled into the domonstratably corrupt government of Ukraine, and inept, agenda- and money-driven media coverage describes how Russian troops are being decimated, Ukraine is looking like North Korea at night. That's about what the whole Earth would look like if we did a wholesale switchover to solar power;-) "It was only a matter of time. The recent Russian pull-back of troops clearly indicated a broad shift in tactics, and the one thing that the Kremlin avoided for several months seemed like the next most logical step - Full spectrum strikes on Ukrainian infrastructure. Initially, Ukraine's media spin suggested that the precision strikes were 'ineffective,' with western news outlets showing only a handful of images of craters in streets and some scarred apartment buildings..."

Low-Pressure Modulation Facts

Low-Pressure Modulation Facts, July 1953 QST - RF CafeAuthor Howard Wright takes the opportunity here in a 1936 issue of QST magazine to distill the concept of modulation down to its basic operation while dispensing with the garbled mix of "graphs, formulas, charts, vectors, diagrams, and Greek letters which often enter into various discussions of modulation." Mr. Wright describes how to the uninitiated radio dial spinner, the culmination of events occurring behind the scenes in an AM reception process is akin to this: "...it might be compared to the reproduction of a color photograph in a magazine. How would we ever know that, to be reproduced, the picture was broken down into its primary colors, if all we had to go by was the original print and the magazine?" That is a very apt comparison...

Transistor Evolution Timelines

Transistor Evolution, IEEE Spectrum - RF CafeIEEE's Spectrum magazine has an interesting article entitled "The State of the Transistor in 3 Charts." Although the first transistor was built in Bell Labs in late 1947, commercial products did not appear until  the mid-1950's, and integrated circuits until the early 1970's. Hence that's where the charts timelines begin. An accompanying article entitled, "The Ultimate Transistor Timeline" accounts for all major developments from the first point-contact transistor on Christmas Eve Eve (sic) in 1947 through to today's newest transistor innovation, the complimentary FET. Note in the chart that there are four transistor types which have been invented but not yet commercialized (as indicated by no black line at the end of the red bar)...

Radio Control Installations

Radio Control Installations, February 1955 Popular Electronics - RF CafeAnyone who has been in aeromodeling for more than a decade or so is familiar with the name William (Bill) Winter. Bill has been in the model airplane realm for longer than a lot of us have been alive and is one of the true pioneers of the sport. He has served as editor for a couple aircraft modeling magazines, and has written countless articles both for the magazines he edited and for other special interest magazines. When Popular Electronics came on the scene in the mid 1950s, Bill was editor of Model Airplane News magazine. Radio control was beginning to mature from its infant state when only hobbyists with an intimate knowledge of electronics were able to participate. Oliver Read, editor of Popular Electronics, tapped Bill's ample knowledge and skill to craft quite a few articles for his own magazine. This one, "Radio Control Installations," appeared in the February 1955 issue. As always when reading this type of vintage material, it is amazing how much innovation has occurred between then and today in the fields of electronics, materials, and construction techniques...

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. 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.

Sunday the 27th

Electronics Theme Crossword for November 27th

Electronics Theme Crossword Puzzle for November 27th, 2022 - RF CafeNovember 27th's crossword puzzle sports an electronics theme. All RF Cafe crossword puzzles are custom made by me, Kirt Blattenberger, and have only words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects. As always, this crossword contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Reginald Denny, Hedy Lamarr, or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

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...

Many Thanks to KR Electronics for Long-Time Support!

KR ElectronicsKR Electronics has been designing and manufacturing custom filters for military and commercial radio, radar, medical, and communications since 1973. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop, equalizer, duplexer, diplexer, 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.

Friday the 25th

Low-Noise R.F. Amplifiers

Low-Noise R.F. Amplifiers, December 1965 Electronics World - RF CafeMy first encounter with a parametric amplifier was in the S-band search radar system I worked on in the U.S. Air Force. That was in the late 1970's - early 1980's, and the radar was an early 1960's era vacuum tube system with a few solid state upgrades. A silicon diode in the receiver detector circuit, and a transistorized parametric amplifier in the receiver front end are the only two that come to mind. I remember the etch school instructors making a big deal out of the parametric amplifier being so great because it could actually improve the SNR of the received signal. Even at the time, in my youthful ignorance, it seems too good to be true, but if an ambassador of Uncle Sam - especially one wearing five times the number of stripes on his sleeve that had I - then surely it must be so. Leap forward a decade in time and I'm working at General Electric Aerospace Division in Utica, New York, freshly endowed with a BSEE degree, and while researching a design for an airborne early warning ECM system, a thought of that miraculous parametric amplifier came to mind. There was no Internet back then, but the place had a very nice technical library. Not much information was available, so I asked a couple of the seasoned radar gurus about it, but none were particularly enthusiastic, so I moved on. Over the years...

Wireless Power Beamed Down from Space

Wireless Power Beamed Down from Space - RF CafeHere's a genius idea: Spend $billions and generate tons of greenhouse gases in building, deploying, and maintaining a system to beam sun power to Earth (which manages to arrive here w/o any help otherwise, and w/o frying airborne birds & planes in the process). "Solar power could be gathered far away in space and transmitted wirelessly down to Earth to wherever it is needed. The European Space Agency (ESA) plans to investigate key technologies needed to make Space-Based Solar Power a working reality through its SOLARIS initiative. Recently in Germany, one of these technologies, wireless power transmission, was demonstrated to an audience of decision-makers from business and government. The demonstration took place at Airbus' X-Works Innovation Factory in Munich. Microwave beaming was used to transmit green energy between two points representing 'Space' and 'Earth' over a distance of 36 meters..."

The Women Behind ENIAC

The Women Behind ENIAC - RF CafeI  never engage in the "woke" practice of promoting certain people because of real or imagined oppression. Nor do I denigrate real or imagined "privileged" people. My decision to acknowledge accomplishments is based on merit and character, regardless of history. If significant enlightening information comes to my attention regarding any aspect of technology and I deem it of value to RF Cafe visitors, it receives front page space. Such was the case with the Hidden Figures movie, and is the case with this "The Women Behind ENIAC" article from IEEE's Spectrum magazine. "If you looked at the pictures of those working on the first programmable, general-purpose all-electronic computer, you would assume that J. Presper Eckert and John W. Mauchly were the only ones who had a hand in its development. Invented in 1945, the Electronic Numerical Integrator and Computer (ENIAC) was built to improve the accuracy of U.S. artillery during World War II. The two men and their team built the hardware. But hidden behind the scenes were six women - Jean Bartik, Kathleen Antonelli, Marlyn Meltzer, Betty Holberton, Frances Spence, and Ruth Teitelbaum - who programmed the computer to calculate artillery trajectories in seconds. The U.S. Army recruited the women in 1942 to work as so-called human computers - mathematicians who did calculations using a mechanical desktop calculator. For decades, the six women were largely unknown..."

The Soaring Sixties

... For the Record: The Soaring Sixties, October 1960 Electronics World - RF Cafe"It is anticipated that within a few years if we do not have new methods and new machinery, there will be a shortage of manpower to produce the goods and services needed to sustain the American standard of living." Those words, noted in this 1960 issue of Electronics World magazine, were uttered in the same year by U.S. Senator Hiram Fong, of Hawaii (first name ring a bell?). His was an admonition against ignoring the need for highly trained workers for the country's burgeoning technical fields. "A few years ago, there were no electronics industries, no atomic energy projects, no missiles or rockets or space vehicles. New vocations, created in the past ten or fifteen years, run the full spectrum of man's pursuits and offer careers undreamed of only a few decades ago." "Fifteen years from now, supersonic airplanes will bring Paris within two hours of New York and Geneva about three hours from Los Angeles. Space travel will approach reality. In 1961 we hope to launch our first man into space with safe return; about 1970, to transport an American astronaut to the moon [accomplished by July 1969]." Senator Fong was prescient in his remarks. His remarks about work ethic would be lambasted today by pols promising work-obviating government handouts and free healthcare in exchange for votes...

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...

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.

Thursday the 24th

Alliance Tenna−Rotor

Alliance Tenna-Rotor, January 1956 Radio-Electronics - RF CafeA few years ago, I posted an article about the restoration and installation of my Alliance Model U−100 Tenna-Rotor. I'm not sure of the exact vintage of my Model U−100 Tenna-Rotor, but this full-page advertisement from a 1956 issue of Radio−Electronics magazine presents the Alliance Tenna-Rotor Model U-98, so mine must be sometime after that. From what I can tell based on the ad, the controller appears to be the same or very similar. "Model U−98 - fully automatic - incorporates 32 distinct improvements - eliminates all arcing and consequent picture distortion - points directly, positively, instantly to target station - 'just set it and forget it!'" It seems they forgot to make a couple other needed improvements. As I mentioned in my article, the ker-chunk, ker-chunk of the solenoid stepping through the angle increments is a very strongly nostalgic memory from the days of yore, back at 114 River Road, in Mayo, Maryland...

Anatech Electronics November 2022 Newsletter

Anatech Electronics November 2022 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his November 2022 newsletter that features his short op−ed entitled "Face Reality: Level 5 Vehicle Autonomy Won't Be Here Anytime Soon." A definition of Level 5 on the level5auto.com website declares thus: "Level 5 driving is full driving automation. That is, the car's systems can accomplish every part of the dynamic driving task (DDT). They can also monitor all of the vehicle's surroundings and make predictions about what the objects in the space around it will do next. Further, the car can do this anywhere. The systems are no longer confined to a limited operational design domain (ODD). And, finally, the car operates without the expectation or need for a human to ever take over driving - even in the case of a system failure." The scheme requires not only perfect AI (artificial intelligence), but perfectly functioning electronics processors, sensors, and control over the car's throttle, steering, and brakes. That's a pretty tall order. As Sam notes, if any monitoring and/or intervention by the human occupant is required, then Level 5 has not been achieved. Level 5 may well be an asymptote of the vehicle autonomy curve...

Record Level RF Signal Synthesis with Quantum Accuracy

Record Level of RF Signal Synthesis with Quantum Accuracy - RF Cafe"NIST, in collaboration with CU Boulder faculty, published a paper titled: 'RF Josephson Arbitrary Waveform Synthesizer with Integrated Superconducting Diplexers' demonstrating results that show a significant step toward a broadband, integrated, quantum-based microwave voltage source with useful power above -30 dBm. This milestone creates new opportunities for improving measurements of high-accuracy RF voltage and power for modern high-speed communications components and instruments. NIST's goal is to advance quantum-based standards for RF communications to eliminate costs and overhead in calibration and traceability chain measurements by providing self-calibrated, quantum-based standards and automated measurement capability to communication and instrument manufacturers. The voltage source is an RF Josephson arbitrary waveform synthesizer (RF-JAWS) that utilizes a superconducting integrated circuit that is cooled to 4K and is composed of an array of 4,500 Josephson junctions..."

Harmonic Radiation from External Nonlinear Systems

Harmonic Radiation from External Nonlinear Systems, January 1953 QST - RF CafeMy introduction to passive intermodulation (PIM) issues was while working on a BTS switching system back around the turn of the century (yes, this century), where because of high power levels, the matrix had to be guaranteed to not generate PIM products greater than a certain value. About 1/3 of the units were not passing test. The cause turned out to be a high power attenuator in one of the paths. The manufacturer of the attenuator was a very well established and reputable firm. The PIM levels were intermittent and would come and go after removing and then replacing the interconnecting cables. I fortunately noticed that the N-type connector on one end of the attenuator was rotating slightly during the process. According to our specification to the manufacturer (it was a custom design), the connector bodies were to be pinned to prevent movement during torqueing. They appeared to be built properly because the small hole where the steel pin was driven had been backfilled with conductive epoxy. When the company was told that the connectors were rotating, they immediately blamed us (me, actually) for abusing the connectors, since there was no way the connectors would move with the pins in place...

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.

Wednesday the 23rd

"As God As My Witness, I Thought Turkeys Could Fly"

WKRP in Cincinnati: "As God As My Witness, I Thought Turkeys Could Fly" - RF CafeAnyone who watched the WKRP in Cincinnati sitcom back in the 1970s has to remember what was one of the funniest episodes ever. Here is the 4 minutes that made Prime Time history. In this Thanksgiving episode, station owner / manager Arthur Carlson decided he would surprise the community with good deed - that doubled as a promotional stunt for his radio station - by dropping turkeys from a helicopter for lucky shoppers at the local shopping mall. Watch the disaster unfold as Les Nessman reports live, and then see Carlson's final comment that is still used or alluded to in many comic routines. Posting this video is an RF Cafe tradition. Have a Happy Thanksgiving!

Electronics-Themed Comics

Electronics-Themed Comics, August 1946 Radio-Craft - RF CafeHopefully, you are winding down operations for the week and getting ready to celebrate Thanksgiving with a long weekend. This trio of electronics-themed comics from a 1946 issue of Radio−Craft magazine will help get you in a jovial spirit, regardless of whether or not you're getting the long weekend. I've mentioned many times that these comics make a good source of levity for adding to your presentations. As you might have guessed if you are familiar with Frank Beaven, he drew the top and bottom comics. He also drew the middle one. Two of these comics are part of his "Radio Term Illustrated" series, where magazine readers sent him suggestions for a theme that could serve, along with his drawing, as a sort of double entendre. Enjoy!

IPP-5004, 100 W Balun Transformer for 30-1500 MHz

IPP-5004, Balun Transformer, 100 W, 180 degree, 30-1500 MHz - RF CafeInnovative Power Products (IPP), with more than 30 years of experience designing & manufacturing RF & microwave passive components, is pleased to introduce the IPP−5004, a unique 3−port Balun that, as a divider, splits an unbalanced input signal at the sum port J1 into a balanced signal output pair at J2 and J3. The balanced signals are equal in amplitude and have a 180° phase shift between them. As a combiner, the Balun will sum the balanced signal pair into one unbalanced output at the J1 sum port. The IPP-5004's unbalanced impedance at the sum port J1 is 50 ohms and the unbalanced impedances at J2 and J3 are 25 ohms referenced to ground. The operating frequency is 30−1500 MHz with a power rating of 100 W. The insertion loss is less than 0.60 dB, main line VSWR is less than 1.35:1, phase balance is ±7° and amplitude balance is ±0.60 dB. This Balun is produced in a small surface mount (SMD) package with a 1.10" x 1.15" footprint and is available on tape and reel to pick and place for high volume applications...

Operation Radio Airwatch

Operation Radio Airwatch, July 1959 Popular Electronics - RF CafeWow, a $50,000 helicopter! You can't touch a new heli these days for less than a third of a million dollars (like a Robinson R22). 1959 marked the early days of helicopter traffic reports, I'm guessing before the really good noise cancellation headsets were available, so drivers down in the traffic snarl tuned in their AM radios and got a lot of reporters yelling into the microphone to overcome the rotor chop-chop-chop sound in the background. According to this 1959 Popular Electronics magazine article, an airborne GE unit of the era transmitted 3 watts at 26.19 mc (MHz), and received on a triple conversion, crystal-controlled receiver. If you look at the one photo, you'll see a Handie-Talkie on the passenger seat...

Many Thanks for Alliance Test Equipment's Support!

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

Flexible Circuits Printed on Curved Surfaces

Flexible Circuits Printed on Curved Surfaces - RF Cafe"Researchers from NC State University have demonstrated a new technique for directly printing electronic circuits onto curved and corrugated surfaces. The work paves the way for a variety of new soft electronic technologies, and researchers have used the technique to create prototype 'smart' contact lenses, pressure-sensitive latex gloves, and transparent electrodes. 'One challenge is that existing techniques require the use of polymer binding agents in the 'ink' you use to print the circuits. This impairs the circuit's conductivity, so you have to incorporate an additional step to remove those binding agents after printing.' 'A second challenge is that these printing techniques typically require you to print on flat surfaces, but many applications require surfaces that aren't flat..."

General Electric Model 280 Tabletop Radio

General Electric Model 280 Tabletop Radio Schematic & Parts List, August 1947 Radio News - RF CafeFor many years I have been scanning and posting schematics & parts lists like this one featuring the General Electric Model 280 tabletop radio. It appeared in a 1947 issue of Radio News magazine. Unlike with most of these documentation sets, no functional description or tuning data was included. I did find a few pages from the John F. Rider (similar to Sams PhotoFacts) service manual - see below. The thumbnail image at the left is a restored GE 280 appearing on the RadioAtticArchives.com website. There is also a shot of the inside showing the chassis, tuning dial, and speaker. There are still many people who restore and service these vintage radios, and often it can be difficult or impossible to find schematics and/or tuning information...

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 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.

Tuesday the 22nd

Mac's Service Shop: TV Without Radio

Mac's Radio Service Shop: TV Without Radio, November 1952 Radio News - RF CafeBy 1952, when this "TV Without Radio" episode of Mac's Radio Service Shop story appeared in Radio & Television News magazine, Mac's technician / protégé Barney had been working there for four years. We know that because the first episode entitled "Mac Hires a Helper" appeared in the April 1948 issue. If after all that time troubleshooting, repairing, and aligning circuits Barney was still using a metal-shafted tool to tweak an IF coupling transformer, either should have been a reason to fire the boy or for Mac to consider whether he had not adequately trained him. During my USAF radar maintenance years in the later 1970's - early 1980's, all techs carried a variety of plastic tuning wands for making adjustments. I did have one tuning wand that had a very small metal tip on the end of the plastic shaft because it was used on a couple tiny (for the day) inductors in the transistorized IFF secondary radar...

Thanks to PCB Directory for Continued Support!

PCB  Directory - RF CafeThe leading website for the PCB industry. PCB Directory is the largest directory of Printed Circuit Board (PCB) Manufacturers, Assembly houses, and Design Services on the Internet. We have listed the leading printed circuit board manufacturers around the world and made them searchable by their capabilities - Number of laminates used, Board thicknesses supported, Number of layers supported, Types of substrates (FR-4, Rogers, flexible, rigid), Geographical location (U.S., China), kinds of services (manufacturing, fabrication, assembly, prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.

Smart Windows Use Polarize Sunlight as Wi-Fi Alternative

Smart Windows Use Polarize Sunlight as Wi-Fi Alternative - RF Cafe"Sunshine streaming through a window could be directly harnessed for wireless data transmission to electronic devices. KAUST researchers have designed a smart glass system that can modulate the sunlight passing through it, encoding data into the light that can be detected and decoded by devices in the room. The use of sunlight to send data would offer a greener mode of communication compared to conventional Wi-Fi or cellular data transmission. Basem Shihada had been exploring data encoding into an artificial light source when he had the lightbulb moment to use sunshine. 'I was simply hoping to use a cell phone camera to record a video of the encoded light stream to try to decode the video to retrieve the data; that's when I thought, why not do the same with the sunlight?' Shihada recalls. 'This would be much easier and can be done over the cell phone camera too..."

New Number Prefixes: Ronna / Ronto and Quetta / Quecto

New Number Prefixes: Ronna / Ronto and Quetta / Quecto - RF CafeZetta (1021), zepto (1023), yotta (10-21), and yocto (10-23) have just been trumped as the largest and smallest, respectively, numerical prefixes by ronna (1027), quetta (1030), ronto (10-27), and quecto (10-30), respectively. The last time new prefixes were added was in 1991. "Measurement scientists and government representatives from around the world voted in favor of adding the new prefixes at the General Conference on Weights and Measures in Versailles, France." From whence came these strange new prefixes, you might ask? "The need for new prefixes led ... to words that began with the only letters not already in use as symbols for units or prefixes: 'r' and 'q.' Ending the multipliers in an 'a' for the large extreme and 'o' for the smaller end of the scale followed the already established path. The prefixes also have the sound of Greek or Latin numbers..." Is it a coincidence that "ronna" contains "nano" along with the new "r?" "Quecto" contains "ecto" (i.e, outer) with "q" and the accompanying "u."

The Packard-Bell Color TV Line

The Packard-Bell Color TV Line, July 1957 Radio & TV News - RF CafeEven if you are even old enough to remember the Packard Bell line of desktop computers that appeared during the PC revolution of the late 1980s, you probably do not know that before making PCs, Packard Bell made television sets. Before that they made radios. Herb Bell and Leon Bell formed the company in 1933, then marketed their first radio model, the 35A. Neither Packard nor Bell had any direct family ties to the automobile maker or the telephone company of similar names, respectively. Packard Bell was sold to Teledyne in 1968, then in 1986, an American businessman named Beny Alagem and a group of Israeli investors bought the Packard Bell name from Teledyne...

SATNow Satcom Component & Equipment Website

SATNow Satcom Component Equipment website - RF CafeA new website named SATNow is online, serving the needs of satellite component and equipment users. A large selection of unique, space qualified items can be found there including sun sensors, star trackers, reaction wheels, earth / horizon sensors, magnetorquers, ACDS systems, and satcom transceivers. Ground station satcom transceivers and antennas, satellite link emulators, redundancy switches, and block upconverters can also be found on SATNow. Even launch related equipment from payload adapters and payload deployers, up through rocket engines and entire rockets can be sourced. Save yourself valuable time by using a website - SATNow - built specifically to locate and present the needs of satellite communications.

The Outlook for Color TV

The Outlook for Color TV, March 1957 Radio & Television News - RF CafeThe first commercial color television broadcast occurred in 1954 during the Tournament of Roses Parade. By the late 1950s, color television sets were becoming popular in homes, but the price, at around $500, was too prohibitive for most people to afford. In 2014 dollars that is equal to around $4,200 (per USBLS), which would allow you to hang a 70" Samsung UHD on the family room wall. This 1957 Radio & Television News magazine article reported that there were only about five major manufacturers (more, actually) making color TV sets, including RCA, Sylvania, Emerson, Westinghouse, Magnavox, Zenith, and Philco. Most or all used a common 21" round CRT. Over the years many television manufactures came and went, and now today there are really only about twice as many TV manufacturers, although many brands are built by the major companies...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. Chances are you have never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed. An intro video takes you through the main features...

Please Thank IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products (IPP) has over 35 years of experience designing & manufacturing RF & microwave passive components. Their high power, broadband couplers, combiners, resistors, baluns, terminations and attenuators are fabricated using the latest materials and design tools available, resulting in unrivaled product performance. Applications in military, medical, industrial and commercial markets are serviced around the world. Products listed on website link to detailed mechanical drawings that contain electrical specifications as well as performance data. Please take a couple minutes to visit their website and see how IPP can help you today.

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