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Today in Science History

Electronics & Tech  Headlines

Tech Industry Headlines - RF Cafe - Archive -

• Electronic Design Salary & Career Survey Open

• Trouble on the Horizon for UK-Based Researchers

• Huawei Deploys New 5G Massive MIMO Outside China

• Tungsten Supply Chain Action Needed

• Earth Threat Satellite Project Unite Chinese, U.S., Russian

• DARPA to Improve How Scientists Handle Simulations

• Telco 5G Fixed Wireless Revenues Set to Skyrocket

• EE|Times Weekend Edition Says Goodbye

• More Starlink Users Mean Slower Speeds

Metallized-Dielectric & Standard Capacitors

Metallized-Dielectric & Standard Capacitors, July 1965 Electronics World - RF CafeThe term "metallized dielectric" at first might seem like an oxymoron. After all, if you add a conductive substance to the dielectric of a capacitor, then you have compromised the integrity of the dielectric as a non-conducting substance. Here's the deal: The dielectric material between the conductive plates does not receive the metallization; a non-conductive (dielectric) material like paper is impregnated with metal and that is used for the plate material. The advantage of this scheme is that the plate material can be thinner, thereby reducing the size of the capacitor package for a given capacitance value. It comes with a price, of course, and that is a lower operational and maximum applied voltage rating. With proper design in circuits like power supplies, metallized-dielectric capacitors can facilitate great space savings. A major benefit of metallized-dielectric capacitors is an ability to self-heal when the plate material develops a short circuit through the dielectric...

Cool Product: 3D-Printed Waveguide & Antennas

SWISSto12 3D-Printed Antenna Matrices - RF Cafe Cool Product3D printing of antenna and waveguide components has been advancing rapidly in the past few years. Early research used plastic that was then coated with a conductive substance. Once 3D printing using a metallic filament was developed to the point that the structure could withstand heat cycling, vibration, and shock associated with aerospace environments, the creation of complex, compound shapes never deemed possible with traditional machining became reality. Using proprietary additive manufacturing techniques developed in-house, virtually any form of waveguide and/or antenna can now be fabricated by companies like Swissto12, based in Switzerland. As can be seen in the included images from the Swissto12 website, the surfaces are not perfectly smooth...

Filter Building Made Easy

Filter Building Made Easy, December 1953 QST - RF CafeDesigning, building, and tuning low frequency filters is much easier for the person without a professional grade suite of software, fabrication, and test equipment than is RF / microwave frequency filters. Most of my design and integration work has been with system level transmit and receive racks for radar and satellite earth station installations, and typically for prototyping and/or very low quantity production. Accordingly, I often used connectorized components cascaded together where each functional block was predefined and tested. I would be handed a system input/output document that specified parameters for gain, phase noise, intercept points, noise figure, group delay, bandwidth(s), power levels, switching and settling times, current consumption, volume, weight, cost constraints, etc. That explains why my software offerings like RF & Electronics Symbols for Visio and RF Cascade Workbook all deal with system level design...

Antenna and Semiconductor Integrated Modules (AIMS)

Altum RF Announces New Grant and Collaboration with ITRI and TMYTEK - RF CafeAltum RF, a supplier of high-performance RF to millimeter-wave semiconductor solutions for next generation markets and applications, announces a new grant and collaboration with Industrial Technology Research Institute (ITRI), the largest applied technology research institution in Taiwan, and TMY Technology Inc. (TMYTEK), a leading mmWave solution provider targeting the 5G/B5G and SATCOM markets. Altum RF, ITRI and TMYTEK will collaborate on an Antenna and Semiconductor Integrated Modules (AIMS) project for satellite communications systems. The grant comes from the Eureka Globalstars Taiwan framework. The project began in August 2022 and is slated to continue for two years. The purpose of the AIMS project is to develop a millimeter-wave antenna-in-package (AiP) module for phased array Ka-band satellite communication systems. Developing this module will make satellite communication systems...

Simple Mathematics for the Service Man (part 2)

Simple Mathematics for the Service Man, October 1930 Radio-Craft - RF CafeIf you are from a family of electronics hobbyists and/or professionals, then there is a good chance your grandfather and possibly even your father kept a handy-dandy list of common circuit design formulas handy. The list here Part 2 includes all the formulas on this page, which dealt primarily with vacuum tubes, the schematics for which were presented in Part 1 of the series. There was not an "app for that" back in those days. Prior to a smartphone in every pocket, notes were pinned to a lab wall or kept in a hand-written notebook...

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...

Many Thanks to Copper Mountain Technologies for 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.

Why No "Postwar" Radios?

Why No "Postwar" Radios?, August 1946 Radio-Craft - RF CafeThis is one of the few times I disagree with Hugo Gernsback. It's not that his conclusion about economics being the reason for the delay in producing promised newfangled radios after the end of World War II is wrong. My problem is that he excuses the manufacturers who blamed delays on the large amount of time and effort required to incorporate all the new technology developed during the war. As Radio-Craft magazine reader C.G. Little wrote in this August 1946 issue, companies were running advertisements a year before V−E Day (May 8, 1945) promising to have all-new radios with wonderful new technology developed from advances made in radio and radar during the defeat of Axis forces. Japan surrendered on V−J Day (September 2, 1945). The fact is those companies had a year to prepare, and the U.S. government was gradually relinquishing control over production facilities as the War Powers Act impositions faded. Nobody was taken by surprise. This was either a case of government-backed propaganda, or false advertising by the manufacturers...

Overnight Charging of EV's Bad for High Density Areas

 - RF CafeAn Electronics Weekly article entitled "Modelling Grid Effects of Electric Vehicle Charging in the Next Decade" references Nature magazine study "Charging Infrastructure Access and Operation to Reduce the Grid Impacts of Deep Electric Vehicle Adoption," which indicated high density areas with currently (no pun intended) stresses electric supply grids will be problematic. It is a Captain Obvious announcement to anyone following the existing issues like a couple weeks ago California telling EV owners not to charge their cars because of the power shortage. It begins: "Researchers at Stanford University have modelled over-night home charging of electric vehicles and predict that it is not the correct strategy, for the Western US, at least. Stanford EV charging model Simulation is based on a model, revealed in March, for charging demand that can be applied to different human populations under different conditions. In a demonstration..."

RCA Victor Model R-78 Radio Service Data Sheet

RCA Victor Model R-78 B1-Acoustic 12-Tube Superheterodyne Radio Service Data Sheet, August 1932 Radio-Craft - RF CafeFor several years I have been scanning and posting Radio Service Data Sheets like this one featuring the RCA Victor Model R-78 B1-Acoustic 12-Tube Superheterodyne floor console radio in graphical format, and run OCR on them to separate the textual content and make it searchable. 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. I will keep a running list of all data sheets to facilitate a search. The RCA Victor Model R-78 B1-Acoustic 12-Tube photo was found on the RadioMuseum.org website...

SATCOM SDR-Enhanced Phased-Array Antennas

Strengthen SATCOM with SDR-Enhanced Phased-Array Antennas - RF CafeBrendon McHugh has an interesting article on the Microwaves & RF website entitled, "Strengthen SATCOM with SDR-Enhanced Phased-Array Antennas." It begins: "Many SATCOM apps require constant communication between the satellite and ground station, which can be difficult with conventional antennas. Phased-array technologies, coupled with SDRs, provide the robust comm link necessary for proper operation. Satellite communication (SATCOM) is one of the pillars of the modern world, with applications including Global Positioning System (GPS) and Global Navigation Satellite System (GNSS) navigation, space research, telecommunications, internet access, weather monitoring, and law-enforcement surveillance. Together with the satellite itself, ground stations are crucial to the SATCOM industry. They transmit and receive data to and from the satellite, process the information, and apply it to different purposes, depending on the application. Therefore, it’s fundamental to ensure an efficient, reliable, and robust..."

Simple Radio Mathematics for the Service Man

Simple Radio Mathematics for the Service Man, September 1930 Radio-Craft - RF Cafe Included in this first of a series of the "Simple Mathematics for the Serviceman" articles that ran in Radio-Craft magazine is another "cheat sheet" full of oft-used formulas. It begins with basic Ohm's law, resistance, inductance, and capacitance, then builds from there. What was valid in 1930 is still valid in 2022. See the October 1930 issue for the next installment that includes yet another handy-dandy cheat sheet of formulas. A couple examples are given...

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.

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.

Ceramic Capacitors

Ceramic Capacitors, July 1965 Electronics World - RF CafeI learned a new word in this issue of Electronics World magazine's special report on ceramic capacitors: "discoidal." It looked like a made-up word to describe something that looks like a disc. Anyway, the July 1965 issue contained a collection of articles on the various sorts of capacitors in use at the time. Other types of dielectrics covered were tantalum, glass, plastic-film, mica, paper, and metallized-dielectric. Ceramic and electrolytic capacitors were by far the most widely used capacitors during the vacuum tube era since they were relatively inexpensive to manufacture and could handle high voltages. Hobbyists who service and/or refurbish vintage electronic equipment still need this information if for no other reason than to verify component values based on color codes. It also helps to know how the electrical properties vary over temperature, frequency, applied voltage, etc., when deciding which type of modern capacitor will best serve as a suitable substitute...

Anatech Electronics September Newsletter

Anatech Electronics September 2022 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his September 2022 newsletter that features his short op−ed entitled "It's Official: DSRC is Dead," where he discusses how the 1999 era (Y2K era remember?) "Dedicated Short-Range Communications (DSRC)," which was allocated 75 MHz of spectrum at 5.9 GHz for "intelligent transportation systems," is no more. "Cellular to Everything (C-V2X)" is its replacement. Also reported is the introduction of C-Band-proof radar altimeters, a THz development grant to NYU's Tandon School of Engineering, and HawkEye 360 developing RF-sensing capabilities for U.S. Army. As always, Sam demonstrates a keen awareness of the industry for which his company, Anatech Electronics, services...

Admiral Model 7C63 Console Radio

Admiral Model 7C63, Chassis 7C1 Schematic & Parts List, December 1947 Radio News - RF CafeThere are still many old-timers and beginning nostalgic collectors out there who nurse heirloom and otherwise procured vacuum tube radios - like this Admiral Model 7C63, Chassis 7C1 - back to health (operating condition) and/or keep them in good health. The thumbnail to the left is an example from the RadioMuseum.org website. While it is possible to purchase schematics, parts lists, and service instructions from many different models, there are still some that have escaped the scanners of those publishers. For those kindred spirits in search of such reference materials, I happily scan, clean up as necessary, and post this collection (see complete list at bottom of page). I have dozens more that will eventually be added over time, so check back later or send me an e-mail if I have an issue (check the lists first, please) of Radio News, Radio-Craft, etc., known to contain the information you need...

"Dilbert" Cancelled in Newspapers Due to Anti-Wokeness Storylines

"Dilbert" Cancelled in Newspapers Due to Anti-Wokeness StorylinesAny day now we'll see a headline about a Stasi (aka FBI) raid on Scott Adams' home at 6:00 in the morning to confiscate his cellphone. Evidently it's not OK to poke fun at the "woke" agenda according to (as of now) 77 newspapers which cancelled the "Dilbert" comic strip. Many newspapers have gone out of business or are on the verge of doing so due to disappearing subscribers. People are sick of having one view forced at them with no counterpoints. I'm sure Adams makes plenty of $$$ from other Dilbert-related ventures, so he probably will not miss the revenue. A lot of people still subscribe to newspapers mainly for comics and puzzles. This will just add to the "go woke - go broke" phenomenon we're witnessing happening to politically correct businesses. Go to Dilbert.com for all your Dilbert needs.

Man Fined for Off-Frequency Operation 

Fined for Off-Frequency Operation, October 1931 QST - RF CafeSince its inception in 1934, the Federal Communications Commission's (FCC) Enforcement Bureau has taken seriously its charter to monitor and protect designated frequency bands against both intentional and unintentional interference. Except for malicious attacks on legitimate operations, most instances of interference are the result of utter ignorance or accidental broadcasting due to inattention to detail (wrong frequency dialed in) or equipment malfunction. Standard practice is to issue an immediate cease and desist order to the offending party, and then go forward with prosecution if compliance does not follow. News stories appear fairly often about pirate broadcasters and idiots exacting revenge on someone else who allegedly offended said idiot. The $500 fine levied on Mr. Winston in 1931 is the equivalent of a $9,938.62 fine in 2022 (see BLS Inflation Calculator). That is a lot of money, but it pales in comparison to the typical $25k and higher fines charged recently to habitually errant Hams. Evidently, his case fell under the intentional interference category...

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.

Electrical Engineering Crossword Puzzle for September 25th 

Electrical Engineering Theme Crossword Puzzle for September 25th, 2022 - RF CafeThis custom made Electrical Engineering theme crossword puzzle for September 25th is provided compliments of RF Cafe. It's a big one with more than 240 words - good for a long flight. 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 puzzle 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!

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...

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.

Electronics-Themed Comics

Electronics-Themed Comics, March 1952 Radio-Electronics - RF CafeTGIF. Even with being self-employed, I still am always glad when Friday gets here. Aside from some morning work posting content for my AirplanesAndRockets.com hobby website, Saturday is my only day completely off from RFCafe.com business. Anyway, a good way to wind down the week is with some good old-fashioned humor. These couple electronics-themed comics from a 1959 issue of Radio-Electronics magazine are literally old-fashioned. The comic on page 52 is actually a tongue-in-cheek criticism aimed at the housewife who must have make a remark about how easy television servicing probably is. However, the technician's response is really not such a bad high-level check of the health of the vacuum tubes. Heater elements burning out was a fairly common cause of a tube being bad. Of course nobody would want to go through and feel all the tubes' temperatures because those suckers can get hot enough to burn...

The Day the U.S. TV Industry Died

The Day the U.S. TV Industry Died - RF CafeNote that while Zenith Electronics (now owned by LG) has only been around 40 years, Zenith has been manufacturing TVs in the U.S. since 1939. Per the IEEE Spectrum article - "Why the last major U.S. television set maker, Zenith, finally gave up. Driven finally into unprofitability in its traditional market by ever stiffer competition from abroad, harmed rather than helped by a decade of economizing cutbacks in research and development, Zenith Electronics Corp. - the sole surviving U.S. manufacturer of television receivers - reportedly plans to call it quits in the business it helped to create and nourish through some 40 years of innovation. Indeed, nothing so neatly reflects the company's present situation as its latest and arguably its second greatest innovation: a flat shadow mask for a flat-faced cathode ray tube hailed everywhere as a major breakthrough. Announced in 1986, the Flat Tension Mask, as it is called, increases the brightness of the cathode ray tube by up to 80%, its contrast ratio by up to 70%, and its resolution by up to 15% over current tube designs, which use a curved face plate and curved shadow mask..."

2011 Chevy Camaro Convertible AM/FM Antenna

2011 Chevy Camaro Convertible AM/FM Antenna Solution - RF Cafe SmorgasbordI have often said that some of the most capable and enthusiastic engineers and technicians - and even managers - I have worked with in my 30-something year electronics career have been amateur radio operators. They are the rare few who are able to combine a hobby passion with a profession that pays for the hobby... kind of like the airline pilot who flies model airplanes or the druggie who works at a pharmacy. Oh, wait, scratch that last example. Here we see a video from Chevrolet where two engineers, one of them a Ham, took up the challenge to replace the AM/FM whip antenna originally planned for the 2011 Camaro convertible with a blended, inconspicuous antenna. Leaked photos of the prototype car showed the whip, which caused Camaro aficionados to descend upon Chevy requesting its removal. The flexible, folding rear window prevented an embedded solution as is the norm for many cars. The ultimate solution? Embed the antenna in the spoiler. Given the retro nature of the Camaro, the hew and cry against the whip antenna is a bit surprising. I had a '69 Camaro SS and a '74 Camaro SS, and of course both had whip antennas. Kirt Blattenberger (circa 1977) 1969 Camaro SS w/350 cu.in. LT−1 engine (Wikipedia says production began in 1970, but actually late 1969) Bracket Racing Trophy from Capitol Raceway According to the video, the two engineers spent 10 months rushing to get the antenna into the spoiler prior to rollout...

Please see the RF Cafe Homepage Archives for previous items of interest...

Exodus Advanced Communications Best in Class RF Amplifier SSPAs
RF Electronics Shapes, Stencils for Office, Visio by RF Cafe
Berkeley Nucleonics Corporation - RF Cafe
Lotus Communication Systems Modular RF Component Building Blocks - RF Cafe
TotalTemp Technologies (Thermal Platforms) - RF Cafe

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About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024


    Kirt Blattenberger,


RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

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