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Tech Industry Headlines

Tech Industry Headlines - RF Cafe- Archive -

Furloughs, Layoffs, CEO Pay Cuts Hit Radio

OneWeb Files for Bankruptcy as Due to COVID-19

• Verizon Makes Pitch for Licensing Part of 6 GHz Band

• To All ARRL Members and ARRL VEC Accredited VEs

• Analog Devices Withdraws Q2/2020 Guidance Due to COVID-19

Huawei Hits Back at U.S.

• Vodafone UK Does Its Bit with Free Unlimited Mobile Data

Engineers in the Covid-19 Era

U.S. Chip Industry Lobbying to Stay Open Despite Virus Concerns

Radio Data Sheet 345 Admiral Model 6RT44-7B1

Radio Data Sheet 345 Admiral Model 6RT44-7B1, April 1947 Radio-Craft - RF CafeWhenever I post any of these Radio Data Sheets from vintage electronics magazines, I attempt to find photos of actual units. Drawings are good, but actually seeing a for-real example is the best option. This Admiral Model 6RT44-7B1 phonograph appears on the Radio Attic's Archive website. As mentioned previously, electronics service shops relied heavily on these Radio Data Sheets that were printed in monthly magazines like Radio-Craft, Radio News, and Radio & Television News. The alternative was purchasing service documentation from the manufacturer (often only available to factory-authorized shops), from Sam's Photofacts, or some other third-party supplier. Of course experience and intuitiveness could substitute for documentation, but as many episodes of John T. Frye's series of "Mac's Radio Service Shop" illustrates, quirky variations in circuits...

Graphene Transistor Amplifier for THz & Light

Graphene Transistor Amplifier for THz & Light - RF Cafe"A new type of graphene amplifier could offer researchers a unique way to access the electromagnetic spectrum. Engineers from Loughborough University have designed an optical transistor out of graphene and a high-temperature superconductor that can amplify terahertz frequencies, and could unlock a whole new field of potential technologies. Terahertz waves (THz) have long fascinated scientists, but unfortunately, their use has been limited by their weak signals. Without an added boost of power, the wavelengths have been too weak for researchers to harness their potential power - until now, that is. The amplifier is deceptively simple, made up of two layers of graphene and the superconductor..."

Probability Stick Broken into 3 Pieces Can Form a Triangle?

Probability Stick Broken into 3 Pieces Can Form a Triangle? - RF Cafe"There's a tricky question asked at Google and Amazon interviews that is bound to stump you. However, worry not as YouTuber Zach Star is here with the solution in this fun video. The question goes like this: let's say you have a stick that you will randomly cut in three pieces. What are the odds that the three pieces created can form a triangle? If the three pieces are about equal in size, you can make a triangle. If, however, you have two much smaller pieces, you can not. It should also be known that for a triangle to be made, the two shortest lengths combined need to be bigger than the third. How does that relate to our question? Well, you have to watch the video for that..."

Z-Comm SMV0912B-LF 865 to 960 MHz VCO

Z-Comm SMV0912B-LF Features Low Phase Noise with Extremely Low Power Consumption - RF CafeZ-Communications, Inc., announces a new RoHS compliant VCO (Voltage-Controlled Oscillator) model SMV0912B-LF. The SMV0912B-LF operates from 865 to 960 MHz within a tuning voltage range of 0 to 2.5 Vdc. This low cost VCO features very clean spectral purity performance of -100 dBc/Hz @10 kHz offset and covers the frequency range with an average sensitivity of 80 MHz/V. The SMV0912B-LF is designed to deliver 3±3 dBm of output power into a 50 ohms load while operating over the industrial temperature range of -40 to 85°C. This high performance VCO is further enhanced by saving precious energy. It consumes a mere 6 mA of current while operating off a 3.0 Vdc supply. The SMV0912B-LF features a typical 2nd harmonic suppression of -10 dBc...

Science & Math Ignorance in the Media

Coronavirus World Map (MSN) - RF CafeQuestion: According to the legend on this graphic, how many confirmed cases of coronavirus do the gray-colored areas have (answer below)? Look at this "Countries with Confirmed Cases of Coronavirus" map used in an MSN.com news story. According to graphic creator Tara, it was provided by the World Health Organization. This is an example of why the news media should not be unquestioningly believed when presenting data. Its reporters are for the most part very scientifically and mathematically ignorant (and some are plain stupid). They do not know how to assimilate and present numerical information, while pompously demanding that everyone listen to the scientists. Answer: Exactly 100. Do you understand why?

Withwave: RF & Microwave Components

Withwave RF & Microwave Components - RF CafeWithwave manufactures an extensive line of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch, board edge, panel mount), calibration kits (SOLT), a fully automated 4-port vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures for calibration and multicoax cable assemblies. Frequency ranges from DC through 110 GHz. Please contact Withwave today to see how they can help your project succeed.

Engineering & Science Crossword Puzzle for April 5

Engineering & Science Crossword Puzzle April 5, 2020 - RF CafeWorking crossword puzzles can be contagious. This April 5, 2020, tech-themed crossword puzzle may even go viral. It contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc., which I have personally built over nearly two decades. That includes the cause for our planet's current dilemma. Many new words and company names have been added that had not even been created when I started in the year 2002. 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...

A Few Winning Words on Hi-Fi

A Few Winning Words on Hi-Fi, July 1963 Popular Electronics - RF CafeComics in modern magazines are a rather rare phenomenon for some reason, but they were fairly regular features up until a couple decades ago. This set of comics from the July 1963 edition of Popular Electronics deals with high fidelity (Hi-Fi) stereo equipment, which was considered somewhat exotic and high-end for many people's budgets in the day. Inexplicably (not), that is about the time that increases in hearing losses among younger people were first being noticed in audiograms.

Skyworks Ultra-Low Power FEM Features 4X Range Extension

Skyworks Ultra-Low Power Front-End Module Features 4X Range Extension - RF CafeSkyworks Solutions is empowering the wireless networking revolution. Skyworks is pleased to launch the SKY66404-11, a 2.4 GHz front-end module (FEM) designed for Zigbee®, Thread, and Bluetooth® (including Low Energy) ultra-low power IoT applications spanning sensors, beacons, smart meters and thermostats, wireless cameras, smoke and CO detectors, and wearables including medical devices. Featuring high-performance in a compact form factor, SKY66404-11 provides increased efficiency, and more than 4X range extension over previous models. The integrated module includes a power amplifier, low-noise amplifier, low-loss bypass path, transmit and receive switches, and digital controls compatible with 1.7 to 3.6 V CMOS levels...

Mary Burke, W3CUL Wins 1956 Edison Award

Mary Burke, W3CUL Wins 1956 Edison Award, April 1957 Radio & TV News - RF Cafe$5,000 in 1956 currency is equivalent to about $46,000 in 2020, per the U.S. Bureau of Labor Statistics' "Inflation Calculator." That is the value of the amateur radio equipment used by Mrs. Mary Burke in her work handling "an average of 3000 messages per month, principally for service personnel overseas." For her tireless wireless efforts, she was the first woman to win the coveted Edison Award Cup (sponsored by General Electric). Most of Mrs. Burke's communications was via Morse code, where she restrained herself to "about 30 words a minute to maintain accuracy". Way to go, Mary!

Wearable Device Camouflages Its Wearer Regardless of Weather

Wearable Device Camouflages Its Wearer Regardless of Weather - RF Cafe"Researchers at the University of California San Diego developed a wearable technology that can hide its wearer from heat-detecting sensors such as night vision goggles, even when the ambient temperature changes. It's a feat that current state of the art technology cannot match. The new technology can adapt to temperature changes in just a few minutes, while keeping the wearer comfortable. The device, which is at the proof-of-concept stage, has a surface that quickly cools down or heats up to match ambient temperatures, camouflaging the wearer's body heat. The surface can go from 10 to 38°C in less than a minute. Meanwhile, the inside remains at the same temperature as human skin, making it comfortable for the wearer. The wireless device..."

Electronic Design's 2019 Continuing Education Survey

Electronic Design's 2019 Continuing Education Survey - RF CafeElectronic Design's 2019 Salary & Career Survey asked readers, among other topics, what their attitudes were regarding continuing education. The main question in that sections was, "What are some of the ways in which you continue your engineering education?" I could not find the total number of respondents to the survey, but of those who did, 87% held a Bachelor's degree or higher. Among resources used to maintain currency in their professions, 60% say they use printed engineering & technology publications while 57% use similar websites. 60% use seminars and webcasts and 65% read whitepapers. 13% attend in-classroom instruction while 31% use online courses. About 45% of employers reimburse costs for seminars and trade shows, 32% pay for college courses, and 23% cover nothing at all. Click the link above for the full report, as well as to access the Job Satisfaction section from last week.

TotalTemp Technologies: Thermal Platforms for −100°C to +200°C

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.

Antenna Principles - Directional Arrays for 300 MHz and Higher

Antenna Principles, April 1947 Radio-Craft - RF CafeThis installment of the multi-month series of articles on antenna principles covers directional arrays for 300 MHz and higher. Keep in mind that in 1947 when this appeared in Radio-Craft magazine, wavelengths of a meter or less were considered to be at the upper end of the operational range. Parabolic reflector antennas were the domain primarily of ground-based installations due to the physical size and weight being prohibitive in airborne platforms, and even then they were rarely used at the time. Most ground and airborne installations were composed of dipole antennas with various configurations of reflector and director elements for desired gain and directivity characteristics. Special applications like for direction finding and longer wavelength radio communications used loop and long wire antennas, respectively. Highly directive dipole...

WithWave HFSS 3D Electromagnetic Connector Simulation Models

Withwave HFSS 3D Electromagnetic Connector Simulation Models - RF CafeWithwave offers ANSYS HFSS 3D EM(Electromagnetic) Simulation Model of board connectors and panel type connectors for customer design. These 3D models allows RF designers and engineers to simulate the RF performance of these connectors which is launched on various types of high frequency PCB. They can reduce time to assemble the connectors and verify the performance prior to placing an order. we hope to make a commitment to give customers better testing & Simulation environment. Design Assistance for ANSYS HFSS Models (version 17.0 or newer) for 3D EM Simulation and 3D Model for Mechanical Layout (STEP file)...

Bell Telephone Labs Project Echo

 Bell Telephone Laboratories Project Echo, November 1960 Electronics World - RF CafeEcho 1 launched in August of 1960, finally allowing America to participate in the Space Race, which until then was roundly being won by the USSR. Electronics magazines of the day were filled with prognostications of the future of space communications. Electronics World dedicated most of their November issue to satellite Earth stations and advancements being made in ultra sensitive receivers and powerful transmitters. Since the earliest satellites were literally metallic balls for reflecting radio signals, it was necessary to optimize both ends of the communications path since there were no circuits onboard the satellite to perform signal processing and re-transmission. Bell Labs, of course, was at the forefront of the technology. In fact a famously serendipitous discovery was made by a couple scientists in 1964 using the very antenna featured in this advertisement...

ConductRF Performance TSA89 Flexible RF Test Cables to 40 GHz

ConductRF Performance TSA89 Flexible RF Test Cables to 40 GHz - RF CafeManufacturing of all our products continues to operate at full capacity as part of the "Essential Business" community. Professional high frequency TSA89 series of RF test cables with performance to 40 GHz. Connector choices include; SMA, Type-N, 3.5mm, 2.92mm, & 2.4mm. Key features: High-frequency point to point cable, light weight rugged flexible cable, low loss <0.68 dB/ft @ 40 GHz, low VSWR < 1.35:1 (Typical < 1.25:1), RF leakage >-100 dB to 18 GHz, temperature rated from -55ºC to 125ºC. Cables are in stock and available immediately from Digi−Key. Here is an interview with ConductRF founder Dean Gammell.

Ultra-Low Threshold Continuous-Wave Lasing in GeSn

1st Ultra-Low Threshold Continuous-Wave Lasing in GeSn - RF Cafe"Transistors in computer chips work electrically, but data can be transmitted more quickly with light. Researchers have therefore been looking for a way to integrate a laser directly into silicon chips for a long time. A team of physicists at the Centre de Nanosciences et de Nanotechnologies (C2N), in collaboration with researchers at Germany's Forschungszentrum Jülich (FZJ) and STMicroelectronics, have implemented a new material engineering method to fabricate a laser microdisk in a strained germanium-tin (GeSn) alloy. They have demonstrated the laser device with a group IV compound, compatible with Silicon, operating with ultra-low threshold and under continuous-wave excitation. Optical data transmission enables significantly higher data rates and ranges than conventional electronic processes, while using less energy. In data centers, optical cables of a length of around 1 meter are therefore standard..."

A Coronavirus (aka Wuhan Flu) Pandemic Thought

A Coronavirus (aka Wuhan Flu) Pandemic Thought - RF CafeWakeup call to everyone: By Ana Swanson in the March 11, 2020 edition of The New York Times newspaper, "While the United States remains a global leader in drug discovery, much of the manufacturing has moved offshore. The last American plant to make key ingredients for penicillin announced it would close its doors in 2004. Chinese pharmaceutical companies have supplied more than 90% of U.S. antibiotics, vitamin C, ibuprofen and hydrocortisone, as well as 70% of acetaminophen and 40 to 45% of heparin in recent years, according to Yanzhong Huang, a senior fellow for global health at the Council on Foreign Relations..."

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    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 Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

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