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Today in Science History

Electronics & Tech  Headlines

Tech Industry Headlines - RF Cafe - Archive -

• 5G FWA Expansion Networks to Utilize 26.5-67 GHz

• Wireless EV Charging Could Pose Threat to AM Reception

• Evidence and Expertise to Guide U.S. Spectrum Policy

• Pentagon Must Act Now on Quantum Computing to Beat Rivals

• Stacked Chips Could Ignite Computing at the Edge

• Winter Field Day 2023 Dates are January 28 and 29

• NIST Joins O-RAN Alliance

• Amateur Satellite FalconSAT-3 Nears Reentry

• Pentagon Strategy for Integrated Satellite Comms Networks

Bell Telephone Laboratories X-Rays

Bell Telephone Laboratories X-Rays, April 1960 Radio-Electronics - RF CafeIs that an early tin foil hat prototype the lady on the cover of this month's Radio−Electronics magazine is modeling? Tin foil hats for RF radiation conspiracy kooks were probably not even a thing back in 1960. In some ways it fits in with the x−ray subject of the Bell Telephone Laboratories infomercial in the same issue. As you can see from the large and ever-growing list of Bell Labs promotions at the bottom of the page, the world's premier telephone company didn't get to the top by luck. Bell engineers and scientists were continually conducting research and development to assure service would be as efficient, affordable, and reliable as possible. Bell Telephone Laboratories was at the leading edge of communications technology, both wired and wireless, since day its founder uttered the words, "Mr. Watson, come here... I want to see you..."

Modelithics' Qorvo GaN Library v23.5.1

Modelithics Releases Qorvo GaN Library v23.5.1 - RF CafeModelithics is pleased to announce the release of version 23.5.1 of the Modelithics Qorvo GaN Library for use with Keysight Technologies' PathWave Advanced Design System (ADS) and Cadence AWR Design Environment®. This latest version offers new models for Qorvo's QPD1025, QPD1028, QPD1425, and QPD1425L discrete GaN-on-SiC HEMTs. Version 23.5.1 also offers 2 new embedding models for the T2G6000528-Q3 and T2G6003028-FL devices. The QPD1025 is an 1,800-W device intended to operate from 0.96 to 1.215 GHz, while the QPD1028 is a 750-W device intended to operate from 1.2 to 1.4 GHz. The QPD1425 and QPD1425L are 300-W devices intended for operation from 1.2 to 1.4 GHz. All four of the new models are Angelov-based models that include features like temperature scaling, self-heating effects, and intrinsic I-V sensing...

Standardized Wiring Diagram Symbols & Color Codes

Standardized Wiring Diagram Symbols & Color Codes, August 1956 Popular Electronics - RF CafeWhen this Standardized Wiring Diagram Symbols & Color Codes feature appeared in a 1956 issue of Popular Electronics magazine, semiconductors were just coming into common use. Therefore, only the simplest components like a diode and bipolar junction transistor (BJT) are included. In fact, the only two types of diodes shown are vacuum tube and selenium. The semiconductor diode is labeled as a crystal rectifier. There is no light emitting diode (LED), field effect transistor (FET), metal oxide semiconductor FET (MOSFET), integrated circuit (IC), or other commonly used modern device. Note also that the "Receptacle 117V" does not show a safety ground connection. The "Vibrator" was a device commonly used to convert direct current (DC) to alternating current (AC). About the only people who will find a use for this information are those who service and/or restore vintage electronic equipment...

EVs Throw Palladium Mega-Rally into Reverse

EVs Throw Palladium Mega-Rally into Reverse - RF Cafe"An era of breathtaking palladium rallies is likely to be ending, analysts said, as rising supply and stagnant demand erode prices of the metal used to neutralize vehicle exhaust emissions. Palladium, once the cheapest major precious metal, rocketed from less than $500 an ounce in 2016 to above $3,400 last March, leaving platinum and gold for dust. Powering the rally was rising demand from automakers who needed more palladium per vehicle to meet tightening emissions standards. Supply could not keep up, leading to huge deficits. That is now changing. Electric vehicles (EVs) that do not need palladium are gaining market share and automakers are substituting some palladium for cheaper platinum in combustion engine vehicles..."

Strays: Doorknob Tubes

Strays: Doorknob Tubes, April 1946 QST - RF CafeAt first I thought maybe this was intended to be an April Fools joke, being that it appeared in an April issue of QST magazine, but it is probably just a coincidence. One of the two topics refers to a "door knob for UHF," which in reality was a glass-encased vacuum tube that was shaped a lot like one of the old glass door knobs. The author penned a humorous take-off. On second thought, maybe this is a Fool's edition now that I have read the second item. All kidding aside, "Strays" concludes with a poem dedicated to those who became "Silent Keys" as a result of World War II...

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 Again for Windfreak Technologies' Continued Support!

Windfreak TechnologiesWindfreak Technologies designs, manufactures, tests and sells high value USB powered and controlled radio frequency products such as RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters. Since the conception of WFT, we have introduced products that have been purchased by a wide range of customers, from hobbyists to education facilities to government agencies. Worldwide customers include Europe, Australia, and Asia. Please contact Windfreak today to learn how they might help you with your current project.

Inventions Wanted

Inventions Wanted, May 1960 Radio-Electronics - RF CafeThe National Inventors Council (NIC) mentioned by Hugo Gernsback in this 1960 Radio-Electronics magazine "Inventions Wanted" article was established in 1940 by the U.S. Department of Commerce. It served as a collection point for inventions that had possible national defense and military uses. In the mid-1950's, NIC's functions were transferred to the National Bureau of Standards (NBS, now NIST). An initial list was published six months earlier, and this list includes both updates to the former items and new requests. A few examples that have been realized at this point are: 913) Low-Loss High-Power Ferrites for Use as Microwave Phase Shifter | 914) A Broad-Band Maser Amplifier for Use in the Microwave Region | 975) A New Method of Electronically (not with frequency change) Scanning an Antenna | 1024) High-Power Broad-Band Solid-State RF Amplifiers | 1057) Solid-State Microwave Oscillators | 1139) Field Portable Digital Radar. What might a 2023 list include? Maybe a fully autonomous robotic foot soldier, an invisibility cloak for man and machine...

Please Thank IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products has been designing and manufacturing RF and Microwave passive components since 2005. We use the latest design tools available to build our baluns, 90-degree couplers, directional couplers, combiners/dividers, single-ended transformers, resistors, terminations, and custom products. Applications in military, medical, industrial, and commercial markets are serviced around the world. Products listed on the website link to detailed mechanical drawings, electrical specifications, and performance data. If you cannot find a product that meets your requirements on our website, contact us to speak with one of our experienced design engineers about your project.

Millimeter Wave-Absorbing Magnetic Materials

Millimeter Wave-Absorbing Magnetic Materials - RF Cafe"KIMS developed the world's first continuous manufacturing technology for millimeter wave-absorbing magnetic materials. A research team led by Dr. Youn-kyoung Baek and Dr. Jung-goo Lee succeeded in developing the world's first technology to consecutively manufacture epsilon iron oxide that can absorb millimeter wave with a high coercive force equivalent to that of neodymium (Nd) magnets. The researchers are in the Department of Magnetic Materials in Powder Materials Division at the Korea Institute of Materials Science (KIMS), a government-funded research institute under the Ministry of Science and ICT. Iron oxide material with a high-coercive epsilon crystal phase is almost the only magnetic material that absorbs ultra-high frequencies which is a potential 6G frequency band. Until now, it was only formed in a nano-sized particle of 50 nanometers or less. Japan succeeded to produce pure epsilon iron oxide..."

Space Simulation Thermal Vacuum Chambers

TotalTemp Technologies: Space Simulation Thermal Vacuum Chambers (TVAC) - RF CafeTotalTemp Technologies, a worldwide leading provider of benchtop temperature chambers and thermal platform equipment, introduces their VmSD49N Thermal Vacuum Test Chamber capable of +175°C to −75°C at 10−6 Torr. It is designed specifically for testing aerospace equipment. 10−6 Torr (1.333224x10−6 mbars, 1.933678x10−8 psi) is the equivalent of 1/760,000,000th of an Earth atmosphere. Aerospace environmental testing in a thermal vacuum chamber allows for the exposing and weeding out potential failures due to temperature extremes and atmospheric pressure or the lack of it in space. With equipment destined for space, the stakes are always higher with the cost to launch, the chance of a failure being catastrophic plus the lack of service calls in space. The process of basic thermal testing in space is a little different than testing for land based systems, mainly because the lack of heat transfer by air. The intentional and unintentional transfer of heat by convection makes a big difference from what might otherwise be a common sense solution in an environment with air. Outgassing of many materials is another consideration that is usually not such a big deal on earth...

Mac's Radio Service Shop: A Breathing Spell

Mac's Radio Service Shop: A Breathing Spell, January 1955 Radio & Television News - RF CafeWe are accustomed these days with stores having "no questions asked" return policies for just about anything. I once watched a guy successfully return a 4" PVC plumbing fitting that had clearly been smeared with glue in the coupling areas. Another time a guy returned a painting drop cloth that was full of paint, declaring that it wasn't what he wanted. The return counter bins of Walmart and other stores are always chock full of stuff. Such was not always the case, though. This episode of Mac's Radio Service Shop from a 1955 issue of Radio & Television News magazine, mentions, among other things, how busy he and sidekick Barney had been right after Christmas doing troubleshooting and repair on various electronic equipment that had been received as gifts. Imagine receiving a radio for Christmas and not being able to simply return it to the store where it was purchased - even with a sale receipt. Nobody would stand for such a situation today...

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 San Francisco Circuits for Continued Support!

San Francisco CircuitsSF Circuits' specialty is in the complex, advanced technology of PCB fabrication and assembly, producing high quality multi-layered PCBs from elaborate layouts. With them, you receive unparalleled technical expertise at competitive prices as well as the most progressive solutions available. Their customers request PCB production that is outside the capabilities of normal circuit board providers. Please take a moment to visit San Francisco Circuits today. "Printed Circuit Fabrication & Assembly with No Limit on Technology or Quantity."

Hall Effect Sensors

Something New in Semiconductors, January 1960 Radio-Electronics - RF CafeAlthough the Hall effect had been known for 80 years when this article appeared in Radio−Electronics magazine in 1960, it was not until research in semiconductor compounds during that same era generated substantial enough voltage potentials for detection and use by circuits of the day that Hall effect sensors became useable in mass production. Indium arsenide (InAs) and indium antimonide (InSb) are two of the early examples. A single Hall effect sensor in 1960 would set you back around $25 - that's $253 in today's money... ouch! Hall effect sensors in small quantities can be bought now from Digi-Key for $2 and change. Modern Hall effect sensors are still made with InAs and InSb, along with gallium arsenide (GaAs), indium phosphide (InP), and even graphene. There is obviously something special about indium (In) that makes it the ideal base metal for Hall sensors. All the elements involved are in the p−block group of the periodic table...

Are Engineering °s Required?

Are Engineering °s Required?, Kirt's Cogitations #222 -  RF CafeBack in my days at defense contractor companies, first as a technician and then as an engineer, it was virtually unheard of for anyone with the title of "Engineer" to not have at least a Bachelor's degree in engineering or science. Only one instance, while at Westinghouse Oceanic Division in Annapolis, MD, comes to mind. I suspect the requirement was dictated by the government, since many times (if not always), part of a proposal included submitting resumes for many of the key personnel who would be working on the project being bid upon. In the commercial realm, again, only one person that I can recall (at Comsat) had achieved the rank of engineer without a degree. Now, after working at a commercial communications IC design and manufacturing company for many years, I have yet to run into any "engineers" who do not have at least a BSEE degree. Is it because people with engineering degrees are so easy to come by that there is no need to even consider someone without the degree? Are there any non-degreed engineers remaining? If so, are they a dying breed that will not be replaced? Probably you, and definitely I...

1-Chip Radar for Autonomous Vehicles

1-Chip Radar for Autonomous Vehicles - RF Cafe"As part of CES 2023, NXP Semiconductors announced a new 28-nm RFCMOS radar one-chip IC family for next-gen autonomous driving systems and advanced driver-assistance systems (ADAS). The new SAF85xx one-chip family works alongside NXP's high-performance radar sensing and processing technologies in one device to address short-, medium-, and long-range radar that meets more NCAP safety requirements. This advanced radar sensing technology plays an essential part in accelerating the development of next-generation ADAS,' said Mr. Hiroshi Kondo, Head of the Safety Systems Business Unit at DENSO Corp. 'We know DENSO will extend its leadership position in ADAS by leveraging NXP's compact high-performance SAF85xx radar SoC..."

Trinity of Inaccuracy: Phase Noise, Jitter and Short-Term Stability

Trinity of Inaccuracy: Phase Noise, Jitter and Short-Term Stability - RF CafeThe stability and therefore usefulness of a system depends heavily on the quality of its reference oscillator. Understanding the cause and ramifications of oscillator imperfections is essential successful system design. Julian Emmerich and Harald Rudolph of KVG Quartz Crystal Technology have a great article on the Microwave Journal website entitled, "The Trinity of Inaccuracy: Phase Noise, Jitter and Short-Term Stability - What Everyone Should Know About Their Measurement and Interrelationships." It begins: "In electrical components and circuits, noise effects with different physical causes occur everywhere. In crystal oscillators there are three primary noise generating mechanisms: A ubiquitous background noise due to the thermal motion of the atoms and molecules of all components creates an insurmountable noise floor, which mainly affects noise far from the carrier (white noise). Noise caused by semiconductor components is called shot noise which has a 1/f dependence on the frequency. The dominant noise source close to the carrier is called flicker noise, which largely depends on the quality of the crystal..."

Telemetering - Vital Link to the Stars

Telemetering - Vital Link to the Stars, November 1959 Popular Electronics - RF CafeTelemetering - the remote sensing and reporting of system parameters via radio link - was just coming of age in the late 1950s when this article appeared in Popular Electronics magazine. It was the age of space payload rocket development (as opposed to artillery and fireworks rockets), high speed jet airliners, and the Pioneer 1 space probe. There was a great need to collect data during the developmental and operational engineering project stages in order to ascertain causes for failures when they occurred and to know what went right when success triumphed. A pinnacle of the newborn telemetering era was Pioneer 1, which carried an image scanning infrared television system to study the Moon's surface to a resolution of 0.5 degrees, an ionization chamber to measure radiation in space, a diaphragm/microphone assembly to detect micrometeorites, a spin-coil magnetometer to measure magnetic fields to 5 microgauss, and temperature-variable resistors to record the spacecraft's internal conditions*. Unfortunately, the launching rocket experienced a malfunction that buggered the flight trajectory, but the craft...

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 16,000 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.

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.

Infrared Guides Missiles

Infrared Guides Missiles, January 1960 Radio-Electronics - RF CafeNot really on point regarding infrared guided missiles as reported in this 1960 issue of Radio−Electronics magazine, but the photo of a Sidewinder missile on the wingtip of an F−104 Starfighter reminds me of back in the early 1980's when I visited the Smithsonian Air & Space Museum in Washington, D.C., and the wingtip of the F−104 hanging there was nearly close enough to touch. I marveled over how incredibly thin it was for an airplane capable of flying at Mach 2 (1,482  mph)*. Missiles or auxiliary fuel tanks (and sometimes experimental instruments) could be attached to that diminutive, yet evidently extremely strong wingtip. AIM−9 Sidewinder missiles went into service in 1956, so they were relatively new when this story was published. As many as 50 countries, including the U.S., still use them today. The current version is Block III, AIM−9M(R). That's the same time (1955) that B−52 Stratofortress bombers, also still in service, were deployed...

Anatech Electronics January 2023 Newsletter

Anatech Electronics January 2023 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his January 2023 newsletter that features his short op−ed entitled "Cellular to Smartphones from Space is Coming." He writes about the rapidly evolving direct-satellite-to-cellphone service being pioneered by AST SpaceMobile. The photo shows their world's largest space-borne phased array BlueWalker 3 antenna, which was lofted into orbit late last year. Using the online Satellite Orbital Decay Calculator to estimate the likely orbital lifetime of the 1,500 kg (3,300 lb), 64.4 m2 (693 ft2), BlueWalker 3 antenna array, initially in a 515 km (320 mi) high orbit, re-entry can be expected in a little under 6 years. It probably has some amount of propellant onboard to help maintain orbital height, thereby extending its lifetime. No doubt the orbit height and antenna size was a tradeoff of coverage area and path loss between the transmitter and receiver. If these LEO antenna arrays get physically and/or numerically much larger, we may experience more frequent solar eclipses. Maybe the companies should lobby governments for funds based on their lowering the global temperature due to decreased sunlight. The way governments work, though, instead they'll fine satellite companies for lowering the efficiency of solar arrays...

Space Electronics

Space Electronics, April 1961 Popular Electronics - RF CafeThe late 1950s and early 1960s were the dawn of the Space Age, beginning unofficially with the launch of Sputnik. Popular Electronics magazine put a lot of effort into educating the public on advances in space electronics, including not just the spaceborne platforms, but also ground tracking and communicating equipment. Much hardware was launched into orbit in the early years without giving much thought to the hazards or space debris. Failures in the form of explosions scattered chunks widely, but fortunately most were low enough to have their orbits degrade and re-enter the atmosphere. One interesting tidbit reported in this article that I didn't know was that the TV camera lens on the TIROS 2 weather satellite was defocused during launch (due to positional shifting from vibration and G forces, I suppose) and crippled the image quality severely...

Acoustics Anagram

Acoustics Anagram, October 1961 Electronics World - RF CafeIsn't an anagram a word game where letters of one word are rearranged to spell another word or series of words? For instance, an anagram for "microwave" is "warm voice," one for ''resistance" is "ancestries," and for "vector" is "covert." If so, then this puzzle is misnamed; it is really a crossword puzzle. Maybe back in 1961 the word anagram included this type of puzzle which appeared in the October issue of Electronics World magazine.. Regardless of the naming error, I did learn a new word: "inertance," which means "the effect of inertia in an acoustic system, an impeding of the transmission of sound through the system..."

What Is a Decibel?

What Is a Decibel?, January 1964 Radio-Electronics - RF CafeThe decibel is not a concept unique to electronics - power, volts, current - although it is undoubtedly most often used there. Probably the next most often used realm for decibels is with sound (audio), which is the subject of this 1964 Radio−Electronics magazine article. The decibel, abbreviated nowadays as "dB" ("db" in the article's era) is nothing more than a logarithmic representation of a dimensionless ratio of increase (positive dB) or decrease (negative dB). As the numerical "deci" implies, a decibel is one tenth of a bel ("B," named in honor of Alexander Graham Bell). It can be applied to any numerical magnitude comparison. Although not normally done, a decibel ratio could be applied to dissimilar units; for instance, a ratio of 100 apples to 50 oranges is 3 dB. Conversely, a ratio of 50 apples to 100 oranges is -3 dB. Mr. King provides the gory mathematical details...

Sky-High Radar | Cosmic Rays | Trial & Error

Sky-High Radar | Trial/Error Machine | Lab Aloft Chases Cosmic Rays | This Brain Squirts, January 1957 Popular Electronics - RF CafeHere are a few tech headlines from the January 1957 issue of Popular Electronics magazine. Sky-High Radar by Sikorsky is a new high-powered airborne search radar. The electronic Trial & Error Machine "differentiates between right and wrong decisions and profits from its own mistakes," making it the perfect gadget for today's environment where any freakish act gets rewarded and eventually normalized. Lab Aloft Chases Cosmic Rays uses a UASF KC-97 Stratofreighter for researching those mysterious and ubiquitous high energy entities which perpetually bombard our Earthly existence. This Brain That Squirts reports on Bendix's prototype carburetor that uses an electronically controlled "electrojector" to inject fuel directly into the cylinder. Now, all of our internal combustion vehicles contain an electrojector...

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

Anatech Electronics RF Microwave Filters - RF Cafe
Innovative Power Products Passive RF Products - RF Cafe
Innovative Power Products Passive RF Products - RF Cafe
Berkeley Nucleonics Corporation - RF Cafe

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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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