Homepage Archive - May 2020 (page 4)

See Page 1 | 2 | 3 | 4 | of the May 2020 homepage archives.

Sunday 31

Radio & Science Crossword Puzzle for May 31st

Radio & Science Crossword Puzzle May 31, 2020 - RF CafeThis week's crossword puzzle is a new type that uses a "free form" layout where the software dynamically creates the word grid, rather than beginning with a predefined grid that it then fills with words. It appears the longer it is allowed to run, the greater the number of words and cross-links it creates. After about 5 minutes, this 19x17 grid is showing 57 words and 61 cross-links... and now an hour later it shows 62 words and 70 cross-links - not overly impressive in my view. The algorithm picks from the same database of thousands of words which I have been creating for over twenty years and contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, familiar company names etc. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure village in the Andes mountains. You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical location like Tunguska...

Friday 29

Mac's Service Shop: Electrostatics at Work

Mac's Service Shop: Electrostatics at Work, February 1973 Popular Electronics - RF CafeElectronics wizard, repairman, and experimenter extraordinaire Mac McGregor, as sort of alter ego of author John T. Frye, provides a brief lesson on electrostatics for his repair shop apprentice wing man Barney (I don't think his last name was ever mentioned). In this 1973 Popular Electronics magazine article, Mac had built two types of electroscopes - one using a pair of pith balls suspended from silk strings and another that was a cobbled-together version of a gold leaf electroscope. His motive was two-fold. First and foremost was to accommodate his own interest in electrostatics, and second to hopefully engender enough curiosity in Barney to cause him to do a dive into science books to learn more. Given the potentially lethal levels of electrostatic charge that builds on TV picture tubes they worked around, gaining a healthy respect for an electrostatic charge...

CEA-Leti Explore 6G Technology Roadmap in mm-Wave Bands

CEA-Leti Explore 6G Technology Roadmap in mm-Wave Bands - RF Cafe"As countries around the world begin rolling out 5G wireless networks, CEA-Leti, a technology research institute, is looking ahead to 6G technologies that will surpass the data-transfer capability of 5G. The wireless communication in mm-Wave bands, ranging from 20 to 300 GHz, is expected to be a key enabling technology for 6G wireless systems. This is because of the huge available bandwidth that can accommodate ultra-high data-rate communications. Within that range of mmWave bands, CEA-Leti's research is investigating D-band, a new spectrum at 140 GHz that may play a major role in 6G wireless communication. In a paper written for the 6G Wireless Summit, which was scheduled to take place in March but got cancelled because of the coronavirus pandemic, CEA-Leti, and Siradel, a French engineering... "

Frequency Modulation Fundamentals

Frequency Modulation Fundamentals, August 1939 QST - RFCafeFrequency modulation (FM) was, is, and always shall be: x(t) = Xc·cos [Ωct + β·sin (Ωmt)], where the carrier is xc(t) = Xc·cos (Ωct), and the modulating signal is xm(t) = β·sin (Ωmt). Yea verily, thus sayeth Edwin H. Armstrong. Amen, brothers and sisters of radio. The methods for generating and degenerating[sic] FM might vary, but the fundamentals do not vary. Mr. Armstrong developed and patented his system of frequency modulation in the late 1920s and early 1930s, so when this article appeared in QST in 1939, FM was still fairly new - or even unknown - to most people. Household radio dials still had only markings for the commercial AM band (520 - 1720 kHz) and, in a few cases, a couple shortwave bands (also AM)...

Withwave Precision Adapters for 2.92 and 3.5 mm

Withwave Precision Adapters for 2.92 and 3.5 mm - RF Cafe Withwave's Precision Test Adapters are designed based on precision microwave interconnection technologies. These new 2.92 mm to 3.5 mm types are manufactured to precise microwave specifications and constructed with male and female gender on both sides. The precision microwave connector interfaces ensure an excellent microwave performance of 1.25:1 (max) VSWR up to 34 GHz.

Microwave Filters, Impedance-Matching Networks, and Coupling Structures

Microwave Filters, Impedance-Matching Networks, and Coupling Structures - RF Cafe"Microwave Filters, Impedance-Matching Networks, and Coupling Structures," by Matthaei, Young, and Jones, is another classic text that was a go-to reference for filter designers before desktop synthesis software was commonplace. It is also available on the Archive.org website - all 1,115 pages of it. While you are at Archive.org, do a search on any topic of interest and likely you will receive more sources than you ever dreamed were available on the Internet. That includes books, technical reports, white papers, magazine articles, videos, audios, music, podcasts, and other media formats. It is truly a unique and indispensible repository of information. The WayBack Machine has been capturing website pages for more than two decades. It has collected pages from RFCafe.com during 888 sessions between October 13, 1999 and May 13, 2020.

KR Electronics: RF & Microwave Filters

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

Thursday 28

Sweden Electronics Market

Sweden Electronics Market, December 27, 1965 Electronics Magazine - RF CafeThis is the electronics market prediction for Sweden, circa 1966. It was part of a comprehensive assessment by the editors of Electronics magazine of the state of commercial, military, and consumer electronics at the end of 1965. Among Sweden's modern-day most recognizable electronics and related manufacturers are Ericsson, Saab Group and Electrolux, in existence in one form or another since 1965. Automotive company Volvo is also among the largest manufacturers there, although not specifically of electronics. A number of contemporary resources are available for obtaining reports (at a cost) on the electronics industry in almost every country on Earth. Among them are "Consumer Electronics in Sweden, August 2019" and "Electronics Industry in Sweden June 2019..."

AWR Web-Based Training Presents mmWave MIMO Radar System Design

AWR Design Environment Web-Based Training Presents mmWave MIMO Radar System Design - RF CafeCadence| AWR will host a free webinar entitled "AWR Software Web-Training on mmWave MIMO Radar System Design," presented by RF filter expert Dr. Tero Kiuru. Overview: This web-based training session uses Cadence® AWR Design Environment® software to illustrate the design of a frequency modulated continuous wave (FMCW) multiple-in-multiple-out (MIMO) radar system for short range high resolution localization of nearby moving objects. Dr. Tero Kiuru, of the VTT Technical Research Centre of Finland Ltd., is an expert in front-end component design. Four-channel transmitter and receiver chips will be designed using a 130 nm silicon germanium (SiGe) process. Measurements will be made with a 4 TX channel and 8 RX channel system and simulation versus measurement results...

Jet Propulsion from Microwave Energy

Jet Propulsion from Microwave Energy - RF CafeThis news item is worth reading if only for the reader comments at the bottom of the page - which is often the best part of any new story, BTW. The author, who extols the virtues of this fossil fuel-less jet propulsion scheme, does not say from whence the the massive amount of energy for generating microwaves comes - an onboard nuclear power generator perhaps. My thought was, considering this research came out of the Institute of Technological Sciences at Wuhan University, China, that the hope is those foreign devils will glom onto the concept to create jet planes and drones with the most massive electromagnetic signature a smart missile could ever hope for. Rumor |one I just made up ;-)|  has it the project is code named COVID, for Cavity Oscillator Velocity-Inducing Deception.

EMC Directory - Largest Online Directory of EMC Testing Labs 

EMC Directory - The Largest Online Directory of EMC Testing Labs - RF CafeEMC Directory, a new addition to the everythingRF network of engineering resources, is the largest online directory of EMC / EMI Testing labs. The website makes it easy for users to find EMC labs based on their location and testing capabilities. Users can specify the application like Automotive, Radio Technology, Industrial, Medical etc. to find labs that can carry out the test in a specific region. They can also find labs based on the testing directive like CISPR 11, FCC Part 15 (Sub part b) or ISO 10605. EMC testing is performed to ensure that the electronic devices: Have sufficient immunity to electromagnetic interference. They do not create excessive electromagnetic radiation EMC Testing is a very important area for most engineers and companies. Regulatory bodies around the world like FCC, CE, have placed limits on the levels of emissions that electronic and electrical products can generate...

Filter Design Classics

"Handbook of Filter Synthesis," by Anatol Zverev - RF CafeIf it seems like I use opening phrases like, "Back in the days before..." and "There was time when..." a lot, it is because I do, and unabashedly so. The measure of oldness of time past is relative and objective, and unless a particular bit of information on a topic has been proven false or unreliable, there is value in its continued existence and in its continued use as a reference. Such is the case of a book that used to be found somewhere in the offices of every electrical design company: "Handbook of Filter Synthesis," by Anatol Zverev. Another filter design standard tome is "The Design of Filters Using the Catalogue of Normalized Low-pass Filters," by Rufolph Saal. General Electric AESD, in Utica, NY, my first company after graduation, had them in the library. The latter has been uploaded in its entirety to Archive.org by RF Cafe visitor Brad B. The former is also on Archive.org compliments of another Good Samaritan. We thank them both.

Atenlab: Over-the-Air RF & Microwave Measurement Systems

Atenlab microwave components - RF CafeAtenlab has been operating in Taiwan for more than a decade, and has sold and installed hundreds chambers around the world. Holistic, affordable Over-the-Air (OTA) measurement systems perform comprehensive measurement and test in a controlled environment. Compact Antenna Test Range (CATR) with one-touch operation supports multiple systems - 2G, 3G, 4G, 5G - and major instrument brands. [M]ulti-probe OTA measurement systems offer reduced time measurements over single-probe systems.

Wednesday 27

A Radioman's Wife Puts in a Good Word

A Radioman's Wife Puts in a Good Word, June 1951 Radio-Electronics - RF CafeIn the days before people were so easily offended by light-hearted poking, it was not uncommon to find magazine articles written by the wives of hobbyist husbands lamenting the habits and proclivities of their matrimonial mates. Over the years I have read many such treatises in model and full-scale airplane, electronics, and Ham radio publications. As with "A Radioman's Wife Puts in a Good Word" from a 1951 issue of Radio-Electronics, they typically start by expressing frustration of having lost their once-doting husbands to alternative loves in the form of hobbies (I once saw a boat named "The Other Woman"). Determined to win back the devotion of their sweethearts, they make a sincere attempt to learn about and be part of whatever hobby or hobbies is/are the cause of abandonment of wife and children. It usually doesn't take long for Friend Wife, as Popular Electronics' Carl Kohler addresses his better half, to decide that try as she may, engendering a sufficient...

Z-Comm Extremely Low Powered Clock VCO in a SUB-L Package

Z-Communications' Extremely Low Powered Clock VCO in a SUB-L Package - RF CafeZ−Communications, Inc., announces the RoHS compliant VCO (Voltage-Controlled Oscillator) model SMV4596L−LF for highly stable clock generators. The SMV4596L−LF covers 4595 to 4598 MHz within a tuning voltage range of 0 to 2.5 Vdc. This low cost VCO consumes typically less than 15mW of power while still delivering phase noise performance of -81 dBc/Hz @ 10 kHz offset. This unparalleled VCO operates off a 2.8 Vdc supply while drawing a mere 5mA of current. The SMV4596L-LF is designed to deliver −1±2 dBm of output power into a 50 ohm load while operating over the industrial temperature range of −40 to 85°C. This remarkable VCO is further enhanced by its better than 1.1:1...

Elon Musk: The Buck Stops Here

Elon Musk: The Buck Stops Here, Falcon 9 - RF CafeAfter decades of politicians and industry titans dodging blame for things that go wrong on their watch and demanding full credit for what goes right, it is refreshing to be read this statement from SpaceX's Elon Musk, "I'm the chief engineer of this thing so I'd just like to say that if it goes right, it's credit to the SpaceX-NASA team. If it goes wrong, it's my fault." This is just ahead of the planned historic launch of NASA astronauts from Cape Canaveral this evening, Wednesday 27th, at 4:33 pm. Astronauts Bob Behnken and Doug Hurley will be launched to the International Space Station in a SpaceX Crew Dragon spacecraft atop a Falcon 9 rocket. The launch is the first time that astronauts have launched from American soil since 2011 when the Space Shuttle program was axed. Since that time we have paid the Communist nations of China and Russia to ferry our astronauts to and from space. Imagine the technology we had to transfer to them to get a safe ride! Watch the launch live on NASA TV.

Gray Market Electronics - Reaping What We've Sown

Gray Market Electronics - Reaping What We've Sown - RF Cafe SmorgasbordGray market electronics components have been a problem for a long time. An extensive article appeared recently in EE Times reporting on a case based on a small operation in south Florida that was importing and re-selling counterfeit parts to military, aerospace, medical, and other product manufacturers. The Feds charged them "with conspiracy, trafficking in counterfeit goods and mail fraud for knowingly importing more than 3,200 shipments of suspected or confirmed counterfeit semiconductors into the United States, marketing some of the products as "military grade" and selling them to customers that included the U.S. Navy and defense contractors." The good news might be that this particular scam operation was caught and stopped, but the bad news is, according to the story, that many more are never prosecuted...

ConductRF High Flex VNA Test Cables for 40, 50 & 70 GHz

ConductRF High Flex VNA Test Cables for 40, 50 & 70 GHz - RF CafeConductRF offers RF Engineers a large selection of Hi Flex cable for vector network analyzers (VNAs). We have standards for applications at 18-40 GHz, 50 GHz & 70 GHz. Our torque resistant connector heads and phase stable constructions ensure great performance for many tests to come. Other key features include: 2.92 mm, 2.4 mm & 1.85 mm connector options, low VSWR & insertion loss, low phase change with flexing, options available swept right angle connectors. ConductRF VNA series provides customers with reliable ruggedized solutions for Lab and Production Vector Network Analyzer testing. With options for 18 GHz, 26.5 GHz, 40 GHz, 50 GHz, & 70 GHz, these cables offer cost leading alternatives to original OEM VNA cable solutions...

Innovative Power Products: RF & Microwave Passive Components

Innovative Power ProductsInnovative Power Products (IPP) has over 30 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. Take a couple minutes to visit their website and see how IPP can help you today.

Tuesday 26

Lamp Bulb Resistors

Lamp Bulb Resistors, April 1947 Radio-Craft - RF CafeMost people who have been in the electronics world for a while know that neon light bulbs* used to be commonly employed as a "pert-near" voltage regulator reference of between 55 and 65 volts, depending on the type. The familiar NE-2 has a turn-on voltage of 65 Vac (90 Vdc), for instance, and the voltage across the terminals remains there with little change regardless of the current through the bulb - a lot like a Zener diode. Neon bulbs are also used as non-invasive RF power detectors. Most people probably do not know, however, that incandescent bulbs also have properties that make them useful for purposes other than just lighting up a dark space. Incandescent light bulbs have been used successfully for voltage regulation and RF power measurement. They have also been used as dummy loads for transmitters. John Parchman details some of these uses...

Triad Turnkey Amplified S-Band Radio for Long-range Links

Triad RF Systems Develops Turnkey Amplified S-Band Radio for Long-range Links from a COTS Silvus StreamCaster - RF CafeTriad RF Systems continues to add to its THPR series of ready-to-install amplified radios. Eliminating the need to integrate standalone components to create a long-range wireless and intelligence, surveillance, and recognizance (ISR) radio links working in S-band, Triad has combined high power RF subsystems with a Silvus StreamCaster model SC4210E-235 core radio that operates from 2,200 to 2,500 MHz. Triad model THPR1012 is an efficiently packaged, highly reliable, dual-channel MIMO, turnkey radio system that includes bi-directional amplifiers (BDAs), RF filtering, real-time power measurements, link diagnostics, and innovative SoC-based monitoring and controls. This integrated amplified radio system delivers maximum power output of 40 W at 9 Mbps on its max power setting, and 10 W at ~60 Mbps on its max data rate setting. Unmanned system engineers can expect dependable RF link stability and up to 10X extra range...

Judge Okays Retrieval of Titanic Marconi Wireless Equipment

Judge Okays Retrieval of Titanic Marconi Wireless Equipment - RF Cafe"A U.S. federal judge has given permission to retrieve the ill-fated RMS Titanic's Marconi wireless gear, which transmitted distress calls from the sinking ocean liner during its maiden voyage. [The judge] ruled that the radio gear is historically and culturally important and could soon be lost within the rapidly decaying wreck. The Titanic sank after striking an iceberg some 370 miles off the coast of Newfoundland in 1912. 'The Marconi device has significant historical, educational, scientific, and cultural value as the device used to make distress calls while the Titanic was sinking,' Judge Smith wrote in her ruling. She said the company would be permitted 'minimally to cut into the wreck' to access the radio room. The National Oceanic and Atmospheric Administration (NOAA) contends that the retrieval expedition is still prohibited under US law and under an international agreement between the US and the UK..."

Many Thanks to Electro-Photonics for Their Continued Support

Electro-PhotonicsElectro-Photonics is a global supplier of RF & Microwave components. Their products include SMT hybrid and directional couplers, wire bondable passive components, mounting tabs, filters, transmission lines, and very useful test boards for evaluating components (spiral inductors, single-layer capacitors). The Electro-Photonics team can support your small R&D design requirements with RF & Microwave test fixtures and save you valuable design and characterization time. Please take a moment to visit Electro-Photonics' website and see how your project might benefit. 

The Broadcasting Goose

The Broadcasting Goose, March 1930 Radio News - RF Cafe"Are we killing the broadcasting goose, layer of many golden eggs?" Dr. Lee de Forest asked in his inaugural address, upon his election to the presidency of the Institute of Radio Engineers. So went the opening editorial in a 1930 edition of Radio News magazine. It was directed at the question of whether excessive, "gratuitous" advertising was going to be so offensive to listeners that they would turn off the set and go back to their former silent worlds. Remember that many, if not most, households, and certainly not automobiles, even had radios at the time. Building an audience was essential to nurturing the new phenomenon of radio, and to saturate the listeners with commercials would surely doom the medium. Dr. de Forest would be truly depressed if he could see the commercial broadcast landscape today with it consisting of 15-20% advertising content and much of the rest filled with political...

Bittele Electronics: PCB Fabrication & Assembly

Bittele Electronics PCB Fabrication - RF CafeSince 2003, Bittele Electronics has consistently provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly services. It specializes in board level turnkey PCB assembly for design engineers needing low volume or prototype multi-layer printed circuit boards. Free Passive Components: Bittele Electronics is taking one further step in its commitment of offering the best service to clients of its PCB assembly business. Bittele is now offering common passive components to its clients FREE of Charge.

Monday 25

Smellevision Now Here!

Smellevision Now Here!, June 1951 Radio-Electronics - RF CafeWe all know that for the most part television stinks. Back in 1951 when this article appeared in Radio-Electronics magazine, the technology was very new and it was considered a miracle not to be wasted on inane programming. Newscasts actually presented news and not opinion, movies and sitcoms cast the nuclear family, law enforcement, the military, religion, and patriotism in a positive light rather than as the purveyors of evil in the world. By the end of the 1960s to early 1970s a lot of that had changed. Political and social agendas weaseled their way into nearly all programming to the extent that terms like "boob tube" and even, yes, "smellivision," became common monikers for television. The form of smellivision presented in this article was granted patent (US2540144A) protection in 1951 under the title, Television with scent effects..."

Thanks to Brad B. for Many New W-J Tech Notes

Watkins Johnson Tech-Notes Archive - RF CafeRF Cafe visitor Brad B. just provided the following Watkins-Johnson Tech Notes for the collection: v5-3, v5-4, v5-5, v5-6, v6-2, v6-3, v6-4, v6-5, v6-6, v8-1, v8-4, v9-1, v9-2, v9-3, v9-4, v9-5, v10-2, v10-5, v10-6. They run the gamut from Solid State Limiting Amplifiers and Antenna Polarizations to Digital Signal Processing for Multichannel Receiving Systems. Many old-timers consider the W-J Tech Notes to be some of the best sources of circuit and systems design guides ever written, especially for military, defense, and aerospace applications.

Carl & Jerry: Feedback

Carl & Jerry: Feedback, May 1956 Popular Electronics - RF CafeIn this episode of John T. Frye's "Carl & Jerry" series, the intrepid pair of teenage electronics hobbyists and Ham radio operators are experimenting with an audio amplifier rig that uses a parabolic dish for concentrating sound waves at a focal point where they have a microphone mounted. Aside from picking up bird noises and a neighbor lady scolding her husband for not properly washing the windows during a round of Spring cleaning, Carl imposes upon Jerry for a lesson in feedback techniques - both positive and negative - and the reasons one is preferred over the other. The story winds up with a clever double entendre comment referring to osculation...'

Resonant Tunneling Diode Performs Beyond Anticipated Speed of 5G

Resonant Tunneling Diode Performs Beyond Anticipated Speed of 5G - RF Cafe"Researchers from the U.S. Naval Research Laboratory have developed a new Gallium Nitride (GaN) based electrical component called a Resonant Tunneling Diode (RTD) with performance beyond the anticipated speed of 5G. David Storm, a research physicist, and Tyler Growden, an electrical engineer, the brains behind the electronic component diode, reported their findings in the academic journal Applied Physics Letters. The work showed that gallium nitride-based RTDs are not inherently slow, as others suggested. They compare well in both frequency and output power to RTDs of different materials. The diodes enable extremely fast transport of electrons to take advantage of a phenomenon called quantum tunneling. In this tunneling, electrons create current by moving through physical barriers, taking advantage of their ability to behave as both particles and waves..."

Alliance Test Equipment: Used & Refurbished, Purchase & Rental

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. Please visit Allied Test Equipment today to see how they can help your project.

Sunday 24

Radio & Science Crossword Puzzle for May 24

Radio & Science Crossword Puzzle May 24, 2020 - RF CafeBeginning in the year 2000 and running through today, May 24, 2020, I have been creating weekly custom technology-themed crossword puzzles for the brain-exercising benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. A database of thousands of words has been built up over the years and contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, familiar company names etc. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure village in the Andes mountains. You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which, if you don't already know, might surprise you.

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