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RF Cascade Workbook 2018 (GS) - RF Cafe
Homepage Archive - July 2018 (page 2)

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page.

Homepage Archive Pages

2018:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2017:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2016:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

See Page 1 | 2 | 3 of the July 2018 homepage archives.

Friday 20

Meter-Reading Quiz

Meter-Reading Quiz, June 1966 Popular Electronics - RF CafeHere is the 46th quiz I have posted from 1960s and 1970s issues of Electronics World and Popular Electronics magazines. Most of were created by Robert P. Balin. I like to save these for Friday afternoons. Guys like me who cut our teeth on analog meters read these indications like a second language. Even novices usually do a good job on the meter needles, but reading a mechanical micrometer (#9) might be more of a challenge, especially if you have never used one before. The same goes for a dial caliper. Can you read the dials on a mechanical gas or electric meter, where some spin CW and others spin CCW? ...

Fairview Skew Matched Cable Pairs with 1 ps Delay Match

Fairview Microwave Debuts New Skew Matched Cable Pairs with 1 ps Delay Match - RF CafeFairview Microwave, a leading provider of on-demand RF and microwave components, has released a new line of 40 GHz skew-matched cable pairs designed for bit-error-rate testing, eye diagrams and differential signals at data rates of 10 Gbps to 28 Gbps. Fairview's new line of skew matched cables consists of three extremely flexible models that are 100% tested for skew match. Performance specs include an impressive VSWR of 1.4:1 and 1 ps delay match. These cable pairs cover two channels with 50 Ohms nominal impedance and a bandwidth of DC to 40 GHz ...

Startup Targets the More Mundane Tasks of Test Engineering

Startup Targets the More Mundane Tasks of Test Engineering - RF Cafe"Test engineering is a global endeavor. Electronic devices can be prototyped thousands of miles from where they are manufactured and ultimately deployed. They must be tested every step of the way. But electrical engineers worlds apart may store test results in different places, which can complicate tasks like debugging glitches and correlating results with test conditions. Santa Clara, California-based startup Gradient One is trying to simplify many of the mundane tasks weighing down test engineering as hardware becomes more complicated. The company has developed a cloud platform for test automation, storage and analysis and other tasks that traditionally have been handled at the test bench ..."

Melting Silicon for Semiconductors

Melting Silicon for Semiconductors, May 1959 Electronics World - RF CafeThis feature appeared at the end of a larger article titled, "RF Induction Heating." A notable difference between the type of induction heating in the other article and the type described here is that rather than directly heating a metallic substance to be treated (melted, bent, tempered, etc.), a "susceptor" (graphite crucible) is used to absorb the field and heat up to melt by conduction (via a quartz liner) the silicon material within. Pure silicon cannot absorb the RF energy sufficiently to be heated directly. Interestingly, if you go to the Wikipedia susceptor page, it has an image of Hot Pockets, which are wrapped in a type of susceptor that produces a crispy exterior while heating the interior. As you are probably aware ...

DARPA Plans a Major Remake of U.S. Electronics

DARPA Plans a Major Remake of U.S. Electronics - RF Cafe"The defense department's research wing is pouring $1.5B into projects that could radically alter how electronics are made. The U.S. Defense Advanced Research Projects Agency is launching a huge expansion of its Electronics Resurgence Initiative, boosting the program to US $1.5B over five years. And while some of the research efforts will be just what you've come to expect from the agency that brought you disposable drones, self-driving cars, and cameras that can see around corners, a lot of this new money is going toward ideas that could fundamentally change how chips are designed. If it all works out, the effect could be ..."

Thursday 19

Mini-Circuits & Vayyar Educational Project Kits for RF Engineers

Mini-Circuits and Vayyar Team up to Offer Educational Project Kits for RF Engineers - RF Cafe"Mini-Circuits is pleased to announce a new partnership with 3D imaging sensor company Vayyar Imaging to offer microwave transceiver project kits with broad applicability for students and university programs spanning topics in electromagnetic theory, RF / microwave engineering, RF systems, and radar technology. The first project kit, UVNA-63 includes all the elements students need to build a fully functioning vector network analyzer, develop S-Parameter algorithms, and perform real-time measurements of 2-port RF devices. The kit comprises Vayyar's high-performance transceiver chip ..."

Whence Come the JK Part of a J−K Flip-Flop?

Whence Come the "JK" Part of a JK Flip-Flop? - RF CafeHint: It's not, as is often claimed, in honor of Jack Kilby (he designed the first commercial IC). Last night while reading an article on T, RS, and JK flip-flop RTL (resistor-transistor logic) ICs, I tried to recall the origin of the "JK" designation. An Internet search turned up lots of claims of Jack Kirby, but fortunately Sourav Bhattacharya posted the true origin in a piece on the Quora website. The origin predates the fame of Jack Kilby, and is remarkably uninteresting. This is another case of a fake story being perpetuated merely because it seems reasonable. I saved a copy of Mr. Bhattacharya's post in case it one day disappears ...

RF Induction Heating

RF Induction Heating, May 1959 Electronics World - RF CafeIf you are interested in the ingenious machines and methods manufacturing engineers dream up for quickly and reliably producing parts and assemblies in large volumes, then you will definitely appreciate this article on RF induction heating. This process of course only works with metallic objects, unlike microwave type heating schemes that work with liquids. Induction heating requires the generated electric, magnetic, or RF field to invoke electrical currents within the metals to increase its temperature. Ohm's law applies here. Have you ever used a torch to heat a metal bolt, wire, car fender, etc., and noticed how it usually discolors the surface and might even produce a crusty oxide layer? An extreme temperature rise as is required for soldering, brazing ...

Anatech Electronics Product Update July 2018

Anatech Electronics Product Update July 17, 2018 - RF CafeAnatech Electronics, Inc. offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. Anatech has introduced three new filter designs: a 1090/60 MHz cavity bandpass filter with N-type connectors, a 150/10 MHz cavity bandstop filter with SMA connectors, and a 2250/100 MHz user-tunable bandpass filter with SMA connectors ...

The Chronicles of GND (Part 2): Single Supply = Multiple Problems

The Chronicles of GND (Part 2): Single Supply = Multiple Problems - RF CafeKendall Castor-Perry has posted Part 2 of "The Chronicles of GND" on the Electronic Design website. "The Filter Wizard's latest installment of 'The Front End' looks at how the ancestral 'split-supply' PCB layouts have mostly ceded to 'single-supply' configurations, and the GND implications that often ensue. When I get a printed-circuit-board (PCB) layout back for review, there are a few things I look for first. I can usually get a feeling for what kind of board designer has been at work, too, specifically if s/he is (or s/he thinks s/he is) a 'digital' designer, an 'RF' designer, or a 'power' designer. You might ..."

IMS 2018 Highlights 5G, Microwaves, Medicine and Mobility

IMS 2018 Highlights 5G, Microwaves, Medicine and Mobility - RF Cafe"The IEEE MTT-S 2018 International Microwave Symposium (IMS), took place in Philadelphia this year from 10-15 of June. The event marked an attendance of over 8,400 attendees. IMS, the annual conference and exhibition of the IEEE Microwave Theory and Techniques Society (MTT-S), is the premier international meeting for technologists involved in all aspects of microwave theory and practice. The six-day event, held at the Pennsylvania Convention Center, drew 4,500 attendees to the technical program and the exhibition featured over 625 exhibiting companies. IMS attendees comprised RF designers, researchers, developers, and academics ..."

Wednesday 18

Speeding Oscillation of Double Heterojunction BJTs

Speeding Oscillation of Double Heterojunction Bipolar Transistors - RF Cafe"Researchers at ETH Zurich in Switzerland claim the fastest quaternary-base double heterojunction bipolar transistor (DHBT) reported to date with maximum oscillation greater than the cut-off frequency, grown by metal-organic chemical vapor deposition (MOCVD). The quaternary base consisted of graded gallium indium arsenide antimonide (GaInAsSb). Adding indium to GaAsSb improves electron transport properties such as mobility and sheet resistance. GaAsSb's conduction band has two types of valley - one at zero wavevector (the Γ point) and one in the 'L' directions of the crystal structure. In GaAsSb, the L-valley is close ..."

Lo! The Russian Radio/TV Serviceman

Lo! The Russian Radio/TV Serviceman, August 1967 Popular Electronics - RF CafeIn 1967, when this parody was published in Popular Electronics, the Iron Curtain of Communist Russia and the Union of Soviet Socialist Republic (USSR) was still firmly in place. Constructing faux Russian-sounding words was common at the time. All a comedian needed to do to have their audiences rolling in the aisles was to append "ski," "ovitch" or "skov" to the end of any word, or add lots of "z"s and "k"s in the middle of words. Tim Conway and Harvey Korman did many hilarious skits on the 1970s' Carol Burnett show where they feigned speaking in German, Japanese, and Russian tongues. Nowadays ...

Many Thanks to ERZIA for Continued Support!

Many Thanks to ERZIA for Continued Support!RF Cafe's continued existence depends on companies like ERZIA providing support. ERZIA produces microwave and mm-wave modular amplifiers and integrated assemblies operating from Low frequencies up to 100 GHz. Their catalogue of standard amplifier modules comprises more than 100 different models, having also a high capacity of customization for amplifiers and integrated assemblies. Some of products have space heritage and are used in aerospace, commercial, military and scientific systems, having a wide range of final applications ...

RF Stencils for Visio v3.1 Available! - Your Support Keeps Me off Welfare ;-)

RF Microwave Wireless Analog Block Diagrams Stencils Shapes for Visio - v3 - RF CafeWith more than 780 custom-built symbols, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every object has been built from scratch to fit proportionally on the provided A- and B-size drawing page templates (you can use your own page if preferred). Components are provided for equipment racks (EIA and ETSI) and test equipment, system block diagrams and conceptual drawings, and for schematics ...

Flann Working with NASA on Space Mission to Map Earth's Water

Flann Working with NASA on Space Mission to Map Earth's Water - RF CafeWorld leading microwave engineering company Flann Microwave is supplying vital components to the U.S. space agency NASA for a major spaceflight mission making the first-ever global survey of Earth's surface water. The multinational Surface Water and Ocean Topology (SWOT) satellite, planned to launch in 2021, is being jointly developed and managed by NASA, the French Space Agency (CNES), and the Canadian Space Agency, with contributions from the United Kingdom Space Agency. It is UK-based Flann's first project for NASA and has seen engineers working closely with their counterparts at NASA's Jet Propulsion Laboratory (JPL) ...

If You're an Engineer, You Need to Be Attending Trade Shows

If You're an Engineer, You Need to Be Attending Trade Shows - RF Cafe"If you want to remain at the top of your game, trade show attendance should be part of every engineer's strategy for growth and continuing education. In this age, you can find out everything you want to know about anything with just a few keystrokes. There are processes, materials, components, and modules for which you can get nearly instantaneous data of all types (pricing, availability, specification, reviews, etc.) via simple online searches. The problem is you have to know what you are searching for. The Internet is a true wonder for researching when you know what you are looking for. But what if something is missing ..."

Tuesday 17

Mac's Service Shop: How It Started

Mac's Service Shop: How It Started, February 1960 Electronics World - RF CafeMac's staff service technician, Barney, asked a great question when he mentioned that Pittsburgh radio station KDKA made the country's first commercial broadcast in 1920: "Who was listening?" It is a reasonable question since prior to the beginning on commercial radio broadcasts there would have been no reason for there to have been a lot of people to own a radio for receiving commercial broadcasts. The answer, of course, is that there were plenty of multi-band radios in homes and businesses for listening in on shortwave broadcast from around the world - a very popular pastime in the era. Just as today we are bombarded with admonitions to not stare at computer monitors or cellphone screens for too long lest we suffer near-sightedness or worse, radio listeners of yore who used headsets were told, "Youths of this generation will never have as protruding ears as some of their older brothers." I suppose ...

A Non-Linear Analysis of the Saturated MOSFET

A Non-Linear Analysis of the Saturated MOSFET - RF CafeBeginning on page 22 of the June 2018 issue of High Frequency Electronics (HFE). "A Non-Linear Analysis of the Saturated MOSFET," by Dr. Alfred Grayzel. "Abstract: The maximum power and the maximum efficiency at the maximum power have been derived for the MOSFET; when the MOSFET is in saturation over the entire cycle, using the square law theory. Results are presented for the following three cases: the gate voltage is a sinusoid, a half sinusoid and a square wave. Results using the square law theory and bulk-charge theory for analysis of the MOSFET are compared ..."

ZipRecruiter® Engineering Job Search Services

ZipRecruiter Engineering Job Search Services - RF CafeZipRecruiter is a relative newcomer to the online job search world. It began in 2010 as a "kitchen table project" by the founders literally in the kitchen of co-founder Ian Siegel. I hear their radio ads frequently. You might have seen ZipRecruiter ads on TV, but I almost never watch TV. The BBB gives ZipRecruiter an A+ rating. If you scan through the user gripes, they appear to be mainly from hiring companies who did not read and/or adhere to the policy for cancellation of the service. Job seeker complaints tend to focus on dissatisfaction with hiring company practices, which you will find with any job posting service. For comparison, Monster gets a D- rating, and CareerBuilder rates an A+. Having no personal experience with ZipRecruiter, I can neither endorse nor condemn them. Marketing Intern Amanda Drury sent me an e-mail asking ...

Resistivity (ρ) & Conductivity (σ) of Metals, Alloys, Rocks, and Soils

Resistivity (ρ) & Conductivity (σ) of Metals, Alloys, Rocks, and Soils - RF CafeI recently created a new reference page titled "Resistivity (ρ) & Conductivity (σ) of Metals, Alloys, Rocks, and Soils." Values for materials are pulled from my copy of Reference Data for Radio Engineers, Sams Publishing. Resistivity, also referred to as specific resistance, is dependent on the nature of the material as well as its volume definition (shape and size). Resistivity is expressed in units that are the product of resistance and length; e.g., Ω·cm. As an example of calculating a volume's resistance, consider the drawing to the left. Assume 12 AWG copper wire with a resistivity of 1.72x10-6 Ω·cm, a cross-sectional area ...

ConductRF D38999 Standard & Custom RF Solutions to 65 GHz

ConductRF D38999 Standard & Custom RF Solutions - RF CafeConductRF is offering standard D38999 RF coaxial cable assembly configurations with RF Contacts including; BMA to 20 GHz SMPM to 60 GHz Size #8 to 18 GHz Size #12 Mil-Spec. Size #16 Mil-Spec. Cable choice include Low Loss Flexible and standard RG styles. Custom marking and also ruggedization coverings including Nomex weave available ...

Electrical Contact to Molecules in Semiconductor Structures for 1st Time

Electrical Contact to Molecules in Semiconductor Structures for 1st Time - RF Cafe"Electrical circuits are constantly being scaled down and extended with specific functions. A new method now allows electrical contact to be established with simple molecules on a conventional silicon chip. The technique promises to bring advances in sensor technology and medicine, as reported in the journal Nature by chemists from the University of Basel and researchers from IBM Research - Zurich in Rüschlikon. To further develop semiconductor technology, the field of molecular electronics is seeking to manufacture circuit components from individual molecules instead of silicon. Because of their unique electronic properties, molecules are suited to applications ..."

Monday 16

Webinar: 5G Cost Structures, Energy Efficiency, Range, and Form Factors

Microwave Journal's Technical Education Webinar Series will present a free webinar titled, "MACOM's Technology Advantage Enables Mainstream 5G Cost Structures, Energy Efficiency, Range, and Form Factors," on July 31, 2018, at 11:00 am EDT. Presented by: Michael Ziehl, VP and GM for RF Power and Basestations, MACOM. Abstract: Deploying 5G networks requires breakthroughs in energy efficiency, superior quality of service and increased subscriber coverage. To meet these stringent requirements, while delivering a reliable solution at commercially viable cost structures, demands true innovation. To date, discussions around 5G have been abundant, but limited information is available on the technology advancements required to make ...

Readouts and Counter Tubes

Readouts and Counter Tubes, October 1959 Electronics World - RF CafeNumeric and to a lesser extent alphabetic displays were complicated and therefore expensive prior to the introduction of LEDs. Display component designers went to a lot of trouble to provide users with easily recognizable characters that did not require difficult interpretation to understand. No matter how competent you get at reading a binary number display, quickly understanding a number large than about 32 (5 bits) requires a display consisting of Arabic numerals (or whatever your usual numeral style is). For some reason I can read Roman numbers up to 4999 almost as easily as Arabic numbers, which is most handy for determining copyright years; e.g., 2018 is MMXVIII. But, I digress. Nixie tubes, which have a stack of shaped ...

Superconductivity References Page Added to RF Cafe

Superconductivity of Metals, Alloys, and Compounds - RF CafeA new reference page on superconductivity has been added to RF Cafe. Values for many superconductive materials are pulled from my copy of Reference Data for Radio Engineers, Sams Publishing. Use of superconducting materials in electrical machinery and transmission lines would mean significant savings in power generation requirements because all supplied power would be converted to useful work. At this point in time there have been test cases of nitrogen-cooled superconducting cables for commercial AC power transmission, but the cost benefit is negative. As of 2015, the highest temperature superconductor compound was mercury barium calcium copper oxide (HgBa2Ca2Cu3O8) at around 133 K ...

Thanks to Copper Mountain Technologies for Continued Support

Copper Mountain TechnologiesCopper Mountain Technologies Vector Network Analyzers - RF CafeCopper 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 ...

140-GHz CMOS Radar-on-Chip with Integrated Antennas

Imec Demonstrates 140-GHz CMOS Radar-on-Chip with Integrated Antennas - RF Cafe"The Belgian research institute expects a prototype in standard 28-nm technology to be ready by the end of 2018. At the recent IMS in Philadelphia, Imec announced development of what it says is the world's first CMOS 140-GHz radar-on-chip system with integrated antennas in standard 28-nm technology. 'With our prototype radar, we have demonstrated all critical specs for radar technology in 28-nm standard CMOS technology,' said Wim Van Thillo, program director at Imec. 'We are well advanced in incorporating multiple antenna paths in our most recent generation solution, which will enable a fine angular resolution of 1.5 cm in a complete MIMO radar ..."

Sunday 15

RF Cafe Engineering Crossword Puzzle w/Weekly Headlines for July 15

RF Cafe Engineering Crossword Puzzle w/Weekly Headlines July 15, 2018At least 10 clues with an asterisk (*) in this technology-themed crossword puzzle are pulled from this past week's (7/9 - 7/13) "Tech Industry Headlines" column on the RF Cafe homepage. For the sake of all the avid cruciverbalists amongst us, each week I create a new technology-themed crossword puzzle using only words from my custom-created related list to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, see someone or something in the exclusion list who or that is directly related to this puzzle's theme, such as Hedy Lamar or the Bikini Atoll, respectively. Enjoy! ...

Friday 13

Electromaze Puzzle

Electromaze Puzzle, June 1966 Popular Electronics - RF CafeRobert Radford's (not to be confused with Robert Redford) "Electromaze" is a unique - and weird - sort of word puzzle that first appeared in the April 1966 issue of Popular Electronics magazine. Some people were confused about the strategy, believing that all the white spaces needed to be filled in. They do not. Just because a letter might have an empty square adjacent to it does not imply that another letter must fill it. You will probably want to print out the maze grid and find an old guy who should still have a pencil stowed away somewhere you can borrow to use for filling in the boxes ...

8 Tips from 350 Million Job Posts

8 Tips from 350 Million Job Posts - RF CafeHiring managers and interviewers take note: This free download titled "8 Tips from 350 Million Job Posts" contains what the hiring data says about improving your next job ad. "Reaching out to the right candidates but can't get them through the door? Using these 8 writing tips will help you fill roles faster, with more qualified people. Check out the report from Textio ..."

Smart Technology Sees Through Walls, Tracks, Identifies People

Smart Technology Sees Through Walls, Tracks, Identifies People - RF Cafe"A group of researchers and students at MIT have developed an intelligent radar-like technology that makes it possible to see through walls to track people as they move around, a development that could prove useful for monitoring the elderly or sick as well as for other applications - but that also raises privacy concerns. Tests show that the technology, known as RF-Pose, can reveal whether someone is walking, sitting, standing or even waving - and can identify individuals from a known group with a success rate of 83%. Its developers say it could prove useful for law enforcement, search and rescue, and - perhaps most ..."

Werbel Microwave Intros "True" 3-Way, 2-18 GHz Splitter

Werbel Microwave Intros "True" 3-Way, 2-18 GHz Splitter - RF CafeWerbel Microwave, a designer and manufacturer of RF and microwave power couplers, dividers, terminations, and DAS equipment, introduces model WMPD03-2-18-S is a wide-band, "true" 3-way splitter/combiner that covers 2-18 GHz in a size measuring 4.46×246×0.38 inches. The unit ships with stainless steel SMA female connectors. ​Features: Provides a "true" 3-way split over the continuous band, which saves about 1.2 dB insertion loss versus using a 4-way splitter with one output terminated. When every tenth of a dB counts, look to Werbel Microwave ...

R.F. - Is It Dangerous?

R.F. - Is It Dangerous?, April 1960 Electronics World - RF CafeThe ubiquitous presence and usage since the 1970s of microwave ovens has made most people aware of the ability of radio frequency (RF) energy to heat substances containing water. Both animate and inanimate objects are included. In 1960, when this article was written, the effort had really just begun to inform the general public about the potential hazards of RF energy depending on its combination of wavelength (frequency) and power. The good news about RF radiation versus beta radiation due to radioactive decay is that the former is not potentially cancer-causing. The latter is termed "ionizing radiation" because it has the ability to knock electrons off their attending atoms, and can cause cancer. Extremely short electromagnetic (EM) wavelengths above the ultraviolet can also ionize atoms, but that is well above the EM spectrum region considered to be RF ...

Implanting Diamonds with Flaws for Quantum Communications

Implanting Diamonds with Flaws Offers Key Technology for Quantum Communications - RF Cafe"Diamonds are prized for their purity, but their flaws might hold the key to a new type of highly secure communications. Princeton University researchers are using diamonds to help create a communication network that relies on a property of subatomic particles known as their quantum state. Researchers believe such quantum information networks would be extremely secure and could also allow new quantum computers to work together to complete problems that are currently unsolvable. But scientists currently designing these networks face several challenges, including how to preserve fragile quantum information over long distances. Now, researchers have arrived ..."

Thursday 12

Can Dry Cells Be Recharged?

Can Dry Cells Be Recharged?, July 1967 Popular Electronics - RF CafeAs one who has been dealing with using and recharging batteries - both individual cells and wired packs - for about five decades, I have used many varieties of chargers and battery chemistries. As you probably know, there are two basic types of cells: primary and secondary. Based on their construction and chemistry, the former are not designed to be recharged while the latter are. Primary cells include zinc-carbon and standard alkaline. Secondary cells include nickel-cadmium (NiCd), nickel-metal-hydride (NiMH), and lithium polymer (Li-Po). Rechargeable batteries can have their discharge cycle reversed by running an externally supplied current through the cell in the opposite direction. Of course there are optimal conditions by which that current must be fed ...

RF Cascade Workbook 2018 - Your Support Helps Keep Me off Welfare ;-)

RF Cascade Workbook 2018 Is Available Now! - RF Cafe
A full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. RF Cascade Workbook 2018 is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. 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 ...

Radio Sextant Tracks Moon

Radio Sextant Tracks Moon, May 1959 Electronics World - RF CafeAccording to Wikipedia, The Navy's USS Compass Island was one of two ships, the other being USS Observation Island, converted and classified as navigational research test vessels under the Polaris Missile system budget. As reported here, the newfangled radio sextant tracks the position of the sun or moon to provide location accuracy much better than the best traditional compass. Remember that in 1959 there was no satellite navigation, and in the middle of the ocean land-based transmitters were useless as radio bearing references. Inertial navigation systems could not hold their calibrations in the harsh physical environment of stormy seas. This radio sextant system is fine as long as the sun and/or moon is high enough in the sky to have antenna pointing access to one or ...

Designing for Peak Power in Mobile Electronic Devices

Designing for Peak Power in Mobile Electronic Devices - RF CafeIn this article, author Kevin Murphy addresses RF transmitter power not from a power amplifier (PA) optimization perspective but from the standpoint of the DC power supply connection. Not all battery compartment contacts are created equal, to paraphrase part of the Declaration of Independence. A poor connection can significantly affect RF power output. Says Mr. Murphy, "Consideration of peak power requirements via careful design and battery selection can dramatically increase battery runtime and, ultimately, customer satisfaction. Most electronic devices exhibit a pulsing behavior, where peak power is much higher than standby power. This includes mobile ..."

Kirigami-Inspired Technique Manipulates Light at Nanoscale

Kirigami-Inspired Technique Manipulates Light at Nanoscale - RF Cafe"Folding and cutting thin metal films could enable microchip-based 3-D optical devices. Nanokirigami has taken off as a field of research in the last few years; the approach is based on the ancient arts of origami (making 3-D shapes by folding paper) and kirigami (which allows cutting as well as folding) but applied to flat materials at the nanoscale, measured in billionths of a meter. Now, researchers at MIT and in China have for the first time applied this approach to the creation of nanodevices to manipulate light, potentially opening up new possibilities for research and, ultimately ..."

Wednesday 11

Tiny Vacuum Tube Rivals Transistor

Tiny Vacuum Tube Rivals Transistor, May 1959 Electronics World - RF CafeThe RCA Nuvistor was a godsend to hardline vacuum tube lovers who were steadfast members of the Never Transistor movement of the 1950s and 1960s. It would hopefully be the miracle invention to obviate the need for replacing tubes with transistors. Of course everyone knew that vacuum tubes would forever be needed for medium and high power applications. Solid state semiconductors could never replace cathode ray tubes (CRTs) for displays or thyratrons for over-the-horizon and commercial broadcast transmitter amplifiers, so why bother with transistors at all? OK, maybe the emotion wasn't that severe, but if you read enough articles from vintage magazines of the tube-to-transistor transition era, you will know that there was ...

Sailing Drone Measures Oceans Autonomously for 12 Months

Sailing Drone Measures Oceans Autonomously for 12 Months - RF Cafe"Saildrone is a Californian company which designs and manufactures wind and solar powered autonomous surface vehicles, called Saildrones, designed to monitor the ocean for months on end. The hard wind design emerged from a decade-long pursuit of the land speed record – company founder Richard Jenkins ultimately achieved 126.2mph in 2009, having started his Windjet Project in 1999 while studying mechanical engineering at Imperial College. Using wind power for propulsion, a Saildrone fleet travels at 3-5kts, with each drone collecting high-resolution data either by holding station or following a survey pattern. The drones sail autonomously ..."

Electronics in Outer Space

Electronics in Outer Space, October 1959 Electronics World - RF CafeYou might know that America's first communications satellite, Pioneer I, failed to obtain a proper orbit due to component failure. However, according to author Jordan McQuay, "[The] first use of a satellite as a radio relay station occurred accidentally during the one-day flight of Pioneer I in October 1958. The electronics payload included a command receiver, which was supposed to trigger a reverse rocket and thus propel the vehicle further into space. Although the rocket failed to function on command, the command signals were instantaneously rebroadcast by the data transmitter aboard the Pioneer I. These command signals were heard half-way around the world!" That was two years before Echo I, a reflective sphere designed to be a passive radio relay platform, was put into orbit in 1960 ...

Many Thanks to Anatech Electronics for Long-Time Support!

Anatech Electronics logo - RF CafeAnatech Electronics RF FiltersAnatech Electronics (AEI) manufactures and supplies RF and microwave filters for military and commercial communication systems, providing standard and custom RF filters, and RF products. Standard RF filter and cable assembly products are published in our website database for ease of procurement. Custom RF filters designs are used when a standard cannot be found, or the requirements dictate a custom approach. Please visit Anatech today to see how they can help your project succeed!

Whitepaper: The College Recruiting Playbook

The College Recruiting Playbook - RF CafeWhether you are hiring a college grad or are a college grad looking to be hired, this could provide some valuable insight into current day practices and expectations. "The college recruiting game has changed. Today's innovative companies aren't just meeting students on campus. They're making offers there. If you're not engaging students in the way they expect before you get to campus, the top talent will be gone by the time you arrive. In this Playbook, you'll learn how to: Identify and close the top graduate talent before your competitors even arrive on campus, Cast a wider net and consider students from more colleges than ever before ..."

Finnish Telco Elisa Claims World's 1st 5G Network Launch

Finnish Telco Elisa Claims World's 1st 5G Network Launch - RF Cafe"Elisa said it is already selling 5G subscriptions for the recently launched service With the advent of a new generation of network technologies come the inevitable battles over 'firsts' - and Finnish mobile telephony operator Elisa has now claimed to be the first operator in the world to begin commercial use of a 5G network, complete with subscription sales in Finland. Middle East telecom group Ooredoo, however, claimed last month that it was the first with a commercial 5G network, with a launch of what it claimed to be first the world's first live 5G network ..."


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Copyright: 1996 - 2018
    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 ...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:  AirplanesAndRockets.com