Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives RF Cascade Workbook 2018 RF Symbols for Visio - Word Advertising Magazine Sponsor RF Cafe RF Electronics Symbols for Visio RF Electronics Symbols for Office Word RF Electronics Stencils for Visio Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Anritsu Alliance Test Equipment Amplifier Solutions Anatech Electronics Axiom Test Equipment Berkeley Nucleonics Bittele Centric RF Conduct RF Copper Mountain Technologies Empower RF everything RF Exodus Advanced Communications Innovative Power Products ISOTEC KR Filters Lotus Systems PCB Directory Rigol RF Superstore San Francisco Circuits Reactel RFCT TotalTemp Technologies Triad RF Systems Windfreak Technologies Withwave LadyBug Technologies Wireless Telecom Group Sponsorship Rates RF Cafe Software Resources Vintage Magazines Thank you for visiting RF Cafe!
RF Cascade Workbook 2018 - RF Cafe

Homepage Archive - April 2016 (page 1)

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. About RF Cafe.

Homepage Archive Pages

2023:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2022:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2021:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2020:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2019:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

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

2015:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2014:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2013:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2012:  1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 (no archives before 2012)

This is Page 1 of the April 2016 homepage archives (click here for Page 2).


5G Work Starts in Earnest

5G Work Starts in Earnest - RF Cafe"In meetings around the globe this week, engineers started in earnest reviewing proposals for a broad suite of standards for 5G. Their work is expected to take at least two years, touching every aspect of wireless networks in ways more sweeping than any prior cellular generation. The 3GPP, which acts as a central organizer for 5G standards, has broken the job initially into nearly a dozen separate study groups covering topics ranging from radio access technologies to network architectures. 'You eat an elephant in small pieces…it takes lots of people to develop these new technologies,' said Karri ..."

Antenna Matching with Line Segments

Antenna Matching with Line Segments, September 1948 QST - RF CafeHow RF circuits work have long been referred to as 'black magic,' even sometimes by people who fully understand the theory behind the craft. To me the ways in which a transmission line - be it coaxial cable, microstrip, or waveguide - can be manipulated and controlled with various combinations of lengths and terminations is what most qualifies as 'magic.' Sure, I know the equations and understand (mostly) what's happening with incident and reflected waves, etc., and how the impedance and admittance circles of a Smith chart graphicaly trace out what's happening, but you have to admit there's something wonderfully mystical about it all ...

Nanoscrolls Created from

Graphene's Imperfect Cousin

Nanoscrolls Created from Graphene's Imperfect Cousin - RF Cafe"Seeking an alternative, a team of researchers is looking to graphene oxide - graphene's much cheaper, imperfect form. Graphene oxide is graphene that is also covered with oxygen and hydrogen groups. The material is essentially what graphene becomes if it's left to sit out in open air. The team fabricated nanoscrolls made from graphene oxide flakes and was able to control the dimensions of each nanoscroll, using both low- and high-frequency ultrasonic techniques. But there's a catch: Graphene does not come cheap. The material's exceptional mechanical and chemical ..."

YL News and Views

YL News and Views, April 1953 QST - RF CafeI wonder why today's editions of the ARRL's QST magazine does not have a column dedicated to the 'YL' (Young Lady, or female in general) contingent of the amateur radio realm? Ham radio, as most -if not all - historically male-dominated hobbies has fairly significant outreach efforts to try attracting women into activities. My Model Aviation magazine has a monthly column written by a lady whose enthusiasm for model airplanes equals that of most males - and she's funny to boot! - but it is not dedicated to female modelers. If there is a girl or woman present at a competition, she is almost guaranteed to receive coverage ...

Flexible Sheet Camera Captures

Images with Unusual Fields of View

Flexible Sheet Camera Captures Images with Unusual Fields of View - RF Cafe"The Columbia team led by professor Shree K. Nayar, T.C. Chang, which includes research engineer Daniel Sims and postdoctoral researcher Yonghao Yue, designed and fabricated a flexible lens array that adapts its optical properties when the sheet camera is bent. This optical adaptation enables the sheet camera to produce high quality images over a wide range of sheet deformations. Sims will present the work at the International Conference on Computational Photography (ICCP) at Northwestern University in Evanston, IL, in May. 'Cameras today capture the world from essentially a single point in ..."

First-Ever D-STAR Satellite

to Launch in April

First-Ever D-STAR Satellite to Launch in April - RF Cafe"The first-ever satellite to carry a D-STAR (Digital Smart Technologies for Amateur Radio) Amateur Radio payload into space is expected to launch on April 22 from Guiana. The OUFTI-1 (Orbital Utility For Telecommunication Innovations) CubeSat is one of three CubeSats developed by student teams under the European Space Agency (ESA) Education Office 'Fly Your Satellite!' program, which is aimed at training the next generation of aerospace professionals. The satellites arrived in South America on March 25, followed by the student teams a few days later ..."

NI Presents

Introduction to Radar Webinar

NI Presents Introduction to Radar Webinar - RF CafeNI will sponsor an "Introduction to Radar" webinar on April 27, 2016 through Microwave Journal's Technical Education Webinar Series. This free, one-hour event will be presented by Scott Bullock, instructor for Besser Associates. The webinar provides an introduction to the theory and operation of radar, which has its roots in military and government systems but is now being adopted commercially—with radar in every automobile not far off. Topics include: Radar Detection and Ranging, Pulse vs. Continuous Wave With Applications, Radar Modulation, Radar Path Budget - Basic Radar Equation ...

Twiss Interferometry Offers New

Approach for Remote Sensing

Twiss Interferometry Offers New Approach for Remote Sensing - RF Cafe"A team from the University of Rochester has shown that fluctuations in 'twisted light' could be exploited for a range of applications, from detecting rotating black holes to object detection by lidar, the light-equivalent of radar. In a paper, published in Science Advances today, the researchers demonstrate that for light from a source such as the Sun, random fluctuations of intensity give rise to correlations of twisted light beams. They showed the presence of these correlations by modifying a now classical experiment called Hanbury Brown - Twiss (HBT) interferometry to focus on the angular ..."

Power Supply Filters

Power-Supply Filters, December 1952 QST - RF CafeHere's a topic that never goes out of style. Without bothering to worry about source and load impedances, this brief tutorial on the fundamentals of power supply filter design using series inductors adn parallel capacitor combinations. The author offers a rule-of-thumb type formula for guessing at a good inductor value based on peak-to-average expected current. This is by no means a comprehensive primer on power supply filter design and is directed more toward someone new to the concept ...

Diamond Quantum Bit is Controlled

Using Light and Sound

Diamond Quantum Bit is Controlled Using Light and Sound - RF Cafe"Physicists in the US are the first to use a combination of light and sound to control the state of a diamond-based quantum bit (qubit) of information. The team used a laser pulse and a sound wave to modify the energy state of an electron in a nitrogen vacancy (NV) centre in diamond. According to the researchers, the technique could be further developed for controlling qubits in a chip-based network of NV centers. A nitrogen vacancy (NV) center occurs when two neighboring carbon atoms in diamond are replaced by a nitrogen atom and an empty lattice site. For anyone trying to build a quantum computer ..."

RFMW Offers Skyworks'

Dual Band SP4T for WiFi 

RFMW Offers Skyworks' Dual Band SP4T for WiFi - RF CafeRFMW, Ltd. announces design and sales support for Skyworks dual-band, internally matched, SP4T switch developed for WiFi applications in the 2.4 and 5 GHz ISM bands. The Skyworks SKY13575-639LF supports access points and CPEs along with WLAN test and measurement equipment. Frequency coverage is from 100 MHz to 6 GHz with a maximum insertion loss of 1.4 dB. Isolation ranges from 26 to 40 dB and the SKY13575-639LF can handle up to 32 dBm of input power for demanding applications ...

Can Silly Patents Help Fight

Frivolous Lawsuits?

Can Silly Patents Help Fight Frivolous Lawsuits? - RF Cafe"Inventors and entrepreneurs have logged years of complaining about the patent system, and there are some good reasons. In 2015, patent litigation rose 13% from the previous year according to a study by Unified Patents, and two-thirds of those suits were brought by non-practicing entities, or so-called 'patent trolls.' Trolls don't make products — trolls buy up patents so they can sue companies that do actually make products. Given that patents on an invention last for 20 years, that's plenty of time to bring a lot of lawsuits. Critics of the system say there are too many frivolous patents. Patents such ..."

Cobham Advanced Electronic Solutions

Seeks RF / Microwave Technician

Cobham Needs an RF Calibration Technician 2016 - RF Cafe

Cobham is seeking an RF / Microwave Technician to work at our San Jose, CA facility. The RF Technician's responsibilities are focused in the area of microwave circuit test, subsystems test to meet shipping schedules. The RF Technician will support production activities within a group concentrating on advanced microwave subsystems for applications including missile front ends, radar receivers, wideband tuners and synthesized sources. Duties include CCAs, and subsystem products, collecting and documenting test data and providing feedback to manufacturing engineers on production products. ...

Sayonara, Japan Semiconductor Inc.

Sayonara, Japan Semiconductor Inc. - RF Cafe"The Japanese semiconductor industry's downfall – by way of a slow death over the past quarter century — is undeniable and well documented. Theories about why Japan's semi industry fell apart are many. But the single reality facing Japanese semiconductor firms is this: They no longer matter in the global market. Tracing the top 10 semiconductor sales leaders all the way back to 1990, Brian Matas, vice president of market research at IC Insights, observed that compared to '1990 when Japanese semi suppliers wielded their greatest influence on the global stage and held six of the top 10 positions ..."

Radar on the Highway

Radar on the Highway, May 1956 Popular Electronics - RF CafeIn the opening scene of "Gladiators," Quintus remarks to Maximus (Russell Crowe), "A people should know when they've been conquered." Such truth is applicable to society today regarding ubiquitous surveillance. Less than two decades ago the media was filled with stories of outrage over the discovery of some new form of monitoring and reporting system having been installed on highways, in shopping malls, along sidewalks, even bathrooms. Since the 9/11 terrorist attacks, anything goes with government snooping. Count the numbers of freedoms you have lost and the inconveniences suffered because of those 19 men with no identifiable common cause (wouldn't want to profile). This story from 1956 shows how long stealth installation ...

Anatech Electronics April Newsletter:

5G and Interference Coming in 2020

Anatech Electronics Newsletter for April 2016 - RF CafeAnatech Electronics, a manufacturer of RF and microwave filters, has published its April 2016 newsletter. As always, it includes both company news and some tidbits about relevant industry happenings. This month, Sam Benzacar discusses the significantly higher level of RF interference that is inevitable with the coming 5G networks and the expected increase in noise levels. Sam refers to 5G as "the most significant change to the wireless industry since Dr. Martin Cooper made the first cellular phone call," because of opening of spectrum beyond the current 3 GHz region - up to as high as 60 GHz ...

Radio and Atom Busting

Radio and Atom Busting, March 1942 QST - RF CafeConnecting a diode backwards across a solenoid coil to shunt potentially damaging current and/or voltages when the supply is turned off is a common trick for saving connected circuitry. Depending on the magnitude of the magnetic field and how quickly the field collapses, some really high voltages can be produced. In fact, the ignition coil and point (now solid state) system in exploits exactly that principle to turn the 12 volts from your car battery into 20-40 kV for firing the spark plugs. Engineers that designed this early cyclotron had limited options for what to use given the state of the art in the early 1940s, and chose to keep the generator permanently connected to the coil (no switch) so that if the controller failed, the coil's energy 15 kgauss magnetic field) would flow back ...

Tiny Nanotubes Move into Fast Lane

Tiny Nanotubes Move into Fast Lane - RF Cafe"For the first time, Lawrence Livermore National Laboratory researchers have shown that carbon nanotubes as small as eight-tenths of a nanometer in diameter can transport protons faster than bulk water, by an order of magnitude. The research validates a 200-year old mechanism of proton transport. A nanometer is one billionth of a meter. By comparison, the diameter of a human hair is 20,000 nanometers. The transport rates in these nanotube pores, which form one-dimensional water wires ..."

NI AWR Adds AntSyn, Antenna

Synthesis & Optimization Technology

NI AWR Software Product Portfolio Adds AntSyn, Antenna Synthesis and Optimization Technology - RF CafeAntSyn™ antenna synthesis and optimization technology has been added to the NI AWR software product portfolio. AntSyn is a new cloud-based Software as a Service (SaaS) antenna design, synthesis, and optimization solution that enables designers to input their antenna engineering requirements and produce antenna designs as outputs. Designed to be used by both experts and those who are relatively new to antenna design, AntSyn addresses the growing need for rapid ...

U.S. Wants Its Satellites to Adapt

to Threats on the Fly in 15 Years

U.S. Wants Its Satellites to Adapt to Threats on the Fly in 15 Years - RF Cafe"As Chinese anti-satellite weapons reach ever higher, the U.S. military is getting serious about satellite constellations that can absorb combat damage and keep transmitting data. It's been almost a decade since China startled the world by destroying a weather satellite in low-Earth orbit about 500 miles up; two years ago, a Chinese test rocket reached an altitude of 6,250 miles. Increasingly, the barriers to attacking the most valuable satellites — the ones 22,300 miles up in geosynchronous orbits that keep them over ..."

NASA Reveals Plans for 2D Printed

Spacecraft Wrap Around Asteroids

NASA Reveals Plans for 2D Printed Spacecraft Wrap Around Asteroids - RF Cafe"From two-dimensional spacecraft that can wrap around an asteroid to printable electronics made from the Martian environment, NASA has revealed the 'pioneering technologies' it has funded in a bid to explore the Universe. While these concepts are still in the early stages, NASA says they have potential to revolutionize future aerospace missions, and those which prove to be feasible may move on to further development. Last week, the space agency revealed the 13 proposals ..."

Vertical GaN Schottky Diode

Combining High Current/Breakdown

Vertical GaN Schottky Diode Combining High Current/Breakdown - RF Cafe"HRL Laboratories LLC in the USA has developed a GaN vertical tunneling Schottky barrier diode that gives good combined on and off performance, compared with vertical Schottky barrier diodes. Gallium vertical SBDs suffer from trade-offs between on-current and reverse bias breakdown. By applying a thin layer of aluminum gallium nitride (AlGaN) as a tunneling barrier, the HRL team allowed a more highly doped drift layer to be used, increasing on-current, without compromising the breakdown voltage. Vertical Schottky diodes and other power devices built using GaN technology could lead to higher current ..."

Meteor Scatter

Meteor Scatter, April 1953 QST - RF CafeMeteor scatter communications is an excellent example of where hobbyists - in this case amateur radio operators - have contributed mightily to technology. It could be argued that a big part of the reason for such occasions is that many people involved in science type hobbies are employed professionally in a similar capacity, and their extracurricular activities are a natural extension of what pays for the pastimes. It seems amazing to me that meteor scatter as a means of achieving upper atmosphere reflections of radio signals went undiscovered until 1953, but evidently that is the case. Meteor scatter is a very popular form of amateur radio challenge ...

Please Welcome IDT

as RF Cafe's Newest Advertiser!

Integrated Device TechnologyFounded in 1980, Integrated Device Technology (IDT) develops system-level solutions that optimize its customers' applications. IDT's market-leading products in RF, timing, wireless power transfer, serial switching, interfaces and sensing solutions are among the company's broad array of complete mixed-signal solutions for the communications, computing, IDT RF Switchesconsumer, automotive and industrial segments. These products are used for development in areas such as 4G infrastructure, network communications, cloud datacenters and power management for computing and mobile devices.

Physicists Discover Flaws

in Superconductor Theory

Physicists Discover Flaws in Superconductor Theory - RF Cafe"University of Houston physicists report finding major theoretical flaws in the generally accepted understanding of how a superconductor traps and holds a magnetic field. More than 50 years ago, C.P. Bean, a scientist at General Electric, developed a theoretical explanation known as the 'Bean Model' or 'Critical State Model.' The basic property of superconductors is that they represent zero 'resistance' to electrical circuits. In a way, they are the opposite of toasters, which resist electrical currents and thereby convert energy into heat. Superconductors consume zero ..."

Carl & Jerry: Anchors Aweigh

Carl & Jerry: Anchors Aweigh - RF CafeJust the other day I saw a greeting card with a sailboat on the front with the words "Anchors Away," on it. It was not meant to be a pun on "anchors aweigh;" the card writer didn't know any better. This episode of "Carl & Jerry" has our teenage Ham radio operators and electronics hobbyists running a newly built model tugboat powered by a steam engine and navigated via a radio control system. As is always the case, no activity of the pair goes without drama of some sort. Author John T. Frye used his writings to present technical topics within the storyline, both in the "Carl & Jerry" series here in Popular Electronics and his earlier "Mac's Radio Service Shop" series that appeared ...

Magnetism Research Brings

High-Temp Superconductivity Closer

Magnetism Research Brings High-Temp Superconductivity Closer - RF Cafe"A research team led by the U.S. DOE's Argonne National Laboratory has discovered that only half the atoms in some iron-based superconductors are magnetic, providing a conclusive demonstration of the wave-like properties of metallic magnetism in these materials. The discovery allows for a clearer understanding of the magnetism in some compounds of iron, the iron arsenides, and how it helps induce superconductivity, the resistance-free flow of electrical current ...

Cobham Advanced Electronic Solutions

Needs an RF Calibration Technician

Cobham Needs an RF Calibration Technician 2016 - RF Cafe

Cobham is seeking a RF Calibration Technician to join our Quality Assurance team. The successful candidate will test, calibrate, and repair of test and measuring equipment, electrical and mechanical, to conform to established standards. Plans sequence of testing and calibration procedures for instruments and equipment according to drawings, schematics, technical manuals, and other specifications. Minimum three year of calibration experience which can be offset by formal metrology training or three years of RF / Microwave technician experience ...

RF & Microwave Engineering

Crossword Puzzle for April 10, 2016

RF & Microwave Engineering Crossword Puzzle for April 10, 2016 - RF CafeFor the sake of avid cruciverbalists amongst us, each week I create a new crossword puzzle that has a theme related to engineering, mathematics, chemistry, physics, and other technical words. You will never be asked the name of a movie star unless he/she was involved in a technical endeavor (e.g., Hedy Lamar). Enjoy!

Low Temperature Inkjet Printable

Transistors Can Be Stacked

Low Temperature Inkjet Printable Transistors Can Be Stacked - RF Cafe"In a paper titled 'Exploiting the colloidal nanocrystal library to construct electronic devices,' co-authors Cherie Kagan, Professor in the School of Engineering and Applied Science, and Ji-Hyuk Choi, then a member of her lab, describe how they exploited the diversity of colloidal nanocrystals to design materials, interfaces, and processes to construct all-nanocrystal electronic devices using solution-based processes. The inks formulated with the tunable colloidal nanocrystals included metallic silver and semiconducting cadmium ..."

Listening Post in the Philippines

Listening Post in the Philippines, April 1946 QST - RF CafeHere is a fascinating story of the ordeal one Catholic priest experienced while serving in the Philippines during the Japanese occupation in World War II. Father Visintainer exploited his personal interest in radio communications to help keep local residents apprised of the war's progress and talk to the outside world. Japanese troops confiscated all the existing shortwave radios and converted them to their own frequencies. Some were re-converted by daring servicemen and then hidden. Batteries were recharged using covert water wheel powered generators located in the woods. Drama hit a peak one day when an attempt to formulate a make-shift battery electrolyte resulted ...

2nd Quantum Revolution a Reality

with Chip-Based Atomic Physics

2nd Quantum Revolution a Reality with Chip-Based Atomic Physics - RF Cafe"A University of Oklahoma-led team of physicists believes chip-based atomic physics holds promise to make the second quantum revolution--the engineering of quantum matter with arbitrary precision - a reality. With recent technological advances in fabrication and trapping, hybrid quantum systems are emerging as ideal platforms for a diverse range of studies in quantum control, quantum simulation and computing. James P. Shaffer, professor in the Homer L. Dodge Department of Physics and Astronomy ..."

NFC & Holographic Business Cards

Near Field Communications (NFC) & Holographic Business Cards - RF Cafe Cool ProductFor not an awful lot of money (about $1.50 each) you can buy business cards that have an NFC antenna and chip built in that will transfer your selected information to an associate's cellphone or tablet computer. Bump your card on someone's phone and have it connect to your LinkedIn or Facebook page, go to your website and/or have a bookmark added, open an e-mail with your address already typed in, have a digital version of your business card appear, download an app, or open a video chat. Each company has its own variety of functions available. A nice feature of the NFC business card is that you can update it online with new information and functionality to reflect contact changes or just about anything that comes as part of the original design package. Many manufacturers provide the capability to monitor ..

Record-Breaking Steel Could Be

Used for Satellite Shielding

Record-Breaking Steel Could Be Used for Satellite Shielding - RF Cafe"A team of engineers has developed and tested a new type of steel with a record-breaking ability to withstand an impact without deforming permanently. The new steel alloy could be used in a wide range of applications, from drill bits, to body armor for soldiers, to meteor-resistant casings for satellites. The material is an amorphous steel alloy, a promising subclass of steel alloys made of arrangements of atoms that deviate from steel's classical crystal-like structure, where iron atoms occupy specific locations. Researchers are increasingly looking to amorphous ..."

All Elements Heavier

Than Helium Are Metals?

Metallicity - RF CafeFactoid: Astronomers consider all elements heavier than helium to be metals. That definition obviously does not jive with the standard chemical definition of a metal, but a concept called 'metallicity' argues that from a star (and therefore the universe) formation perspective, extremely high temperatures and pressures in first generation stars (like our sun) preclude the identification of distinct elements other than hydrogen and helium. Heavier elements, such as lithium - #3 on the periodic chart and actually considered a metal in ...

New State of Matter Detected

New State of Matter Detected - RF Cafe"According to the University of Cambridge website, an entirely new state of matter has been detected in a two-dimensional material. The state is known as quantum spin liquid and it causes electrons to break into pieces. This new state of matter is mysterious because it was previously thought that electrons were indivisible building blocks of nature. This new state was predicted forty years ago but had not been observed until now. Quantum spin liquids were thought to be hiding in certain magnetic materials but they had never before been seen in nature ..."

Wired Wireless

Wired Wireless, March 1942 QST - RF CafeAs you might know, particularly if you are a frequent RF Cafe visitor, amateur radio operators (Hams) were prohibited from broadcasting during the entirety of World War II, (see War Comes) ostensibly as a security measure. The concern was that people might unintentionally (or intentionally) convey information on troop positions and family names, domestic factory locations and activities, and the general state of the nation in regards to attitude and finance. Unlike today, that type of data was not easily gathered even by a dedicated deployment of internal spies. In the early 1940s, the majority of amateur radio activity was carried out in the form of Morse code, and operators were understandably concerned ...

Graphene Microchip

for Terahertz Communication

Graphene Microchip for Terahertz Communication - RF Cafe"Scientists in Switzerland have discovered yet another unique property of graphene, the 2D version of carbon. Not only is graphene fast, strong, thin, and lightweight, but now we know that it is also both transparent and opaque to radiation. The Swiss team took advantage of this property to develop a microchip that filters out unwanted radiation. Their device, called an optical isolator, works in the previously untapped frequency band called the terahertz gap. With further development, wireless devices that use the chip to communicate via the terahertz ...

Fellow USAF Radar Tech

Merton Horne Checks In

Merton Horne Added to USAF Radar Maintenance Shop Member List - RF CafeThe unofficial USAF MPN-13 & MPN-14 Radar Maintenance Shop member list has just been expanded to include Merton Horne! From 1971 to 1973, Merton worked on an MPN-14 at Grand Forks AFB, in North Dakota. He wrote asking whether I recall the weight of the ASR transmitter chassis, which I do not. He estimates 180 lbs. If anyone knows for sure, please apprise me and I'll pass it on. If you were or are currently a radar maintenance technician and send me your service info, I will be glad to add you to our list ...

Cooling Chips With the Flip of a Switch

Cooling Chips With the Flip of a Switch - RF Cafe"Turn on an electric field, and a standard electrocaloric material will eject heat to its surroundings as its internal dipoles reorder themselves. Do the same thing, and a negative electrocaloric material will absorb heat, cooling the environment, thanks to the blend of ferroelectric polymers that make up each. While these materials have been investigated as a method of on-demand microclimate control for quite some time, there's a catch - the external field needs to remain active, which is energy-consuming and ends up heating the material. Recently, however, researchers at Pennsylvania State University ..."

Vintage Radio Service Data Sheets

RCA Victor Model 5M 5-Tube Auto Superhet. Receiver Radio Service Data Sheet, July 1936 Radio-Craft - RF CafeThese might be the last two Radio Service Data Sheets that I have to post for a while since I believe they are the last from my current collection of vintage magazines. One is for the RCA Victor Model 5M 5-Tube Auto Superheterodyne Receiver and the other is for the International Kadette Model 400 4-Tube Battery-Operated Superheterodyne Receiver. This makes a total of 104 scanned and made available for collectors, restorers, and researchers.

3D-Printed Satellite Antenna

Is Just One Piece

3D-Printed Satellite Antenna Is Just One Piece - RF Cafe"With an eye toward building space-qualified RF components for Earth observation and science instruments, the European Space Agency (ESA) has 3D printed a satellite antenna designed as a single part. The antenna is now being tested in the agency's Compact Antenna Test Facility, located at ESA's ESTEC technical center in the Netherlands. The prototype antenna is the agency's first dual-reflector type to be 3D printed, according to its designer, Maarten van der Vorst. It incorporates the two reflectors and a corrugated feedhorn ..."

Explosive Charges Bring down

48 VOA Towers in North Carolina

Explosive Charges Bring down 48 VOA Towers in Beaufort County - RF CafeThis item appeared on the ARRL news website. It links to a video showing an engineered demolition of a shortwave antenna farm in North Carolina commissioned by the Voice of America (VOA) in 1963, during the Cold War. The video provides an aerial view of the entire line of towers collapsing as the precisely timed charges go off. The most impressive aspect is that explosives are detonated only on every other tower in such a way that the falling tower takes out the one next to it almost in a dominoes manner (see yellow circle). 25 pounds of explosives were used rather than possibly 50 if every tower's guy lines had been ...

Pasternack Coaxial Packaged

Noise Sources up to 60 GHz

Pasternack Expands Lines of Coaxial Packaged Noise Sources to Cover Frequency Bands up to 60 GHz - RF CafePasternack, a leading provider of RF, microwave and millimeter wave products, has greatly expanded their lines of coaxial packaged noise sources covering frequency bands up to 60 GHz. Various types of noise source design configurations are available including octave band and broadband noise sources, amplified noise sources, noise sources with integral isolators, and precision calibrated instrumentation grade noise sources. Pasternack's new noise sources might generally be used as a reference source to measure system level noise figure for test and measurement applications. But more specific ...

The Square-Corner Reflector Beam

Antenna for Ultra High Frequencies

The Square-Corner Reflector Beam Antenna for Ultra High Frequencies - RF CafeA new word has been added to my personal lexicon: 'sphenoidal.' Author John Kraus used it to describe the wedge shape of a corner reflector. The Oxford Dictionary defines 'sphenoid' thusly: "A compound bone that forms the base of the cranium, behind the eye and below the front part of the brain. It has two pairs of broad lateral 'wings' and a number of other projections, and contains two air-filled sinuses." This 'square corner' configuration - essentially a "V" shape, is shown to exhibit up to 10 dB of gain while being relatively (compared to a parabolic reflector) insensitive to physical size and driven radiator placement across a wide band when made sufficiently large. No radiation pattern was ...

Army Eyes Open-Systems

Digital Radio and EW

Army Eyes Open-Systems Digital Radio and EW - RF Cafe"U.S. Army researchers are reaching out to industry for new ways to build combination digital radio, surveillance, and electronic warfare (EW) systems that are compact enough for Army aircraft and ground vehicles. These systems must be small size, weight, and power consumption (SWaP), and make maximum use of open-systems standards like OpenVPX for embedded computing, VICTORY for on-board networking, the Modular Open RF Architecture (MORA) for RF and microwave systems, and REDHAWK interfaces for software interoperability. Officials of the Army Contracting Command at Aberdeen Proving Ground, Md., issued a sources-sought ..."

The Official Arduino Starter Kit

The Official Arduino Starter Kit - RF CafeDon't let not knowing how to pronounce "Arduino" (click for audio) keep you from joining in on an immensely popular hobby / professional opportunity (Tip: the word is Italian, so you need to make that circle with thumb and forefinger when saying "Arduino," like a chef does when talking about a delicacy). Many books and videos have been produced to help you get started - for less than $80. The Official Arduino Starter Kit walks you through the basics of using the Arduino in a hands-on way. You'll learn through building several creative projects. The kit includes a selection of the most common and useful electronic components with a 170-page book of 15 projects. Starting the basics of electronics, to more complex projects, the kit will help you control the physical world with sensor and actuators ...

Photonic Circuit Design Coming

of Age in Fabless Ecosystem

Photonic Circuit Design Coming of Age in Fabless Ecosystem - RF Cafe"While it is still lagging about 30 years behind electronic integration in terms of maturity, it is a quickly evolving technology. It experienced its greatest development at the telecom bubble around 2000, where millions of passive optical components for fiber networks started to be integrated into planar lightwave circuits (PLC) made out of silica. Nowadays, there are several mature material platforms available for fabless chip development, each of them excelling at different features: PLC because of its low loss and low cost passive circuits, silicon (Si) because of its compactness and CMOS compatibility, indium phosphide (InP) because of its capability of generating and amplifying light on a chip, and silicon nitride (Si3N4) ..."

How's Your Math?

How's Your Math?, December 1942 QST - RF CafeIf you are just starting out in the realm of electronics or maybe just need a little freshening up of your basic math skills, this rather extensive article from a 1942 issue of QST magazine is just what you need. Author Dawkins Espy does a really nice job of laying out the basics of algebraic operations, Ohm's law, trigonometry, and logarithms. Examples are provided for each category. In this day of calculators doing all the hard work of calculating logs, antilogs, and trig functions, it does even seasoned veterans at electronics calculations a bit of good to do a quick read-through to knock off cobwebs in the gray matter. How long has it been since you have seen tables of sine, cosine, and tangent values and/or tables of logarithms? Not long enough, you say? ...

Notable Tech Quote:

Anon Profundities

Notable Tech Quote 4-5-2016, Math Lesson - RF Cafe"Dear algebra: Stop asking us to find your 'x': He's not coming back."

"Möbius strippers never show you their backsides."

"All generalizations are false, including this one."

"A polar bear is a rectangular bear after a coordinate transform."

"It is a miracle that curiosity survives formal education."

"I don't care what it is, when it has an LCD screen, it makes it better."

"We are each entitled to our own opinion, but no one is entitled to his own facts."

"Polaroids /n./: what polar bears get from sitting on ice caps." ...

Pentagon Names 8 Companies

to Support $7.2B Electronics Program

Pentagon Names 8 Companies to Support $7.2B Electronics Program - RF Cafe"The Pentagon plans to spend up to $7.2B over the next dozen years to upgrade old and/or unreliable electronics through the Defense Department. The Defense Microelectronics Activity has awarded contracts to eight companies for the work under the Advanced Technology Support Program IV (ATSP4) program. Under the indefinite-delivery/indefinite-quantity, multiple award contract, the companies will compete for work in solving problems with 'obsolete, unreliable, unmaintainable, underperforming, or incapable electronics hardware and software,' according to a DOD announcement.  The goal is to apply advanced technology insertions and applications to raise the performance ..."

Powell Crosley's Flying Flea

Powell Crosley's Flying Flea - RF CafeSomehow, I missed this. After attending the funeral for my uncle Rick Blattenberger at Arlington National Cemetery, Melanie and I spent a few hours at the nearby Udvar-Hazy Center annex of the Smithsonian National Air and Space Museum. I photographed a lot of cool stuff, including electronics packages used on airplanes, rockets, balloons, and satellites, but in some inexplicable way I managed to not see this bright red "Flying Flea" that was owned by Powell Crosley, Jr., owner of the Crosley Radio Company in Cincinnati, Ohio. It wasn't until a couple nights ago when I saw it featured in the April/May issue of Air & Space magazine that I even knew it existed. Mr. Crosley's company dabbled in many types of domestic products other than just radios ...

Microagents with

Revolutionary Potential

Microagents with Revolutionary Potential - RF Cafe"Salvador Pane was on a trolleybus in Zurich one day after work. He was deep in thought when the bus came to a sudden stop because the cable was disrupted. He was struck by an idea: 'Why can't we create a icrorobot that generates an electric field wirelessly?' The idea stayed with him and, as a result, the ETH researcher and his colleagues have since succeeded in creating tiny particles that can be precisely controlled by magnetic fields and also generate electric fields. This may sound relatively unspectacular to the uninitiated, but it is a breakthrough. What makes it unique is that a microstructure with a single source of energy is not only moved, but also can be ..."

Flexible Coaxial Cable

Flexible Coaxial Cable, April 1946 QST - RF CafeIf anything qualifies for meeting the criteria of the old adage that says "Necessity is the mother of invention," it is coaxial transmission cable. Wireless communications during World War II was the necessity that drove the rapid development and continuous improvement of coax. Other than materials technology for wire, dielectric, protective jacket, etc., the basics of coax cable have not changed. It was during the war that polyethylene was developed and adopted as a dielectric material much superior to previously used copolene. Understanding of how electromagnetic fields propagate within and, under non-ideal conditions - on the outside of the cable has increased significantly ...

Flat Boron is a Superconductor

Flat Boron is a Superconductor - RF Cafe"Rice University scientists have determined that two-dimensional boron is a natural low-temperature superconductor. In fact, it may be the only 2-D material with such potential. Rice theoretical physicist Boris Yakobson and his co-workers published their calculations that show atomically flat boron is metallic and will transmit electrons with no resistance. The work appears this month in the American Chemical Society journal Nano Letters. The hitch, as with most superconducting materials, is that it loses its resistivity only when very cold, in this case between 10 and 20 kelvins. But for making very small superconducting circuits, it might be the only game in town ..."

RF | Microwave Engineering &

Technician Jobs for April 4, 2016

RF | Microwave | Wireless Engineering & Technician Jobs for April 4, 2016 - RF CafeAs a service to RF Cafe visitors, I offer to list open job listings for engineers, technicians, engineering managers, engineering sales, etc., at no charge. Only positions relevant to my readers are included. Your company is welcome to submit job descriptions, so please let your HR department know bout this invitation. Beginning today, I am also going to peruse the websites of RF engineering companies in search of qualifying job postings and will link directly to them. Don't let the news about layoffs and hiring freezes scare you ...

Project Engineering Manager

     - General Dynamics

Electronic Technician - Aeroflex

Radar Test Engineer

    - General Dynamics <many more>

10 of the Greatest Hoaxes

in Engineering History

10 of the Greatest Hoaxes in Engineering History - RF Cafe"What better time to read about some of history's greatest hoaxes than April Fools Day? This year we've compiled another list of some more of our favorite hoax inventions, scams, conspiracies, and urban legends. Did you ever get an email about a secret super car? Maybe you have a friend who has warned you about chemtrails, or maybe you'd like to use a nanotech spray to make yourself invisible? Come take a look at our latest crop of great hoaxes ..."

Voices in the Mail

Voices in the Mail, August 1956 Popular Electronics - RF CafeThis article reports on the very earliest form of voice mail - recording a message on a reel-to-reel tape deck, placing it in an envelope, and snail mailing it to its recipient. Sure, it was slow, but unless you were under surveillance for some suspected crime, there was just about zero chance that some government agency was going to hear your private message. I had forgotten about it until reading this, but I remember that back in the 1960s, my father bought an el cheapo tape deck for our family and one for his parents, who lived in Buffalo, New York. My parents and four sisters and I had a pretty good time hamming it up on the tape, and looked forward to receiving a reply tape a month or two later. "Grandpa B," as we kids called him, was a real funny guy ....

Silicon and Graphene Combo Achieve

Lithium-Ion Battery Greatness

Silicon and Graphene Combo Finally Achieve Lithium-Ion Battery Greatness - RF Cafe"Silicon electrodes crack and break after just a short number of charge/discharge cycles. Meanwhile, the use of graphene on electrodes is limited because graphene's attractive surface area is only possible in single stand-alone sheets, which don't provide enough volumetric capacitance. Layer the graphene sheets on top of each other to gain that volumetric capacity, and you begin to lose that attractive surface area. Now researchers at Kansas State University claim to have developed a technique that uses silicon oxycarbide that makes the combination of silicon and graphene achieve its expected greatness as an electrode material ..."

Congrats to March Book Drawing

Winner Marek K. of Ottawa, Canada !

RF Cafe Quiz #64: Space-Time Adaptive Processing for RadarMarek K., of Ottawa, Canada, is one of the the March 2016 RF Cafe Book Drawing winners! Marek wisely selected Space-Time Adaptive Processing for Radar, by J. R. Guerci. (graciously provided by Artech House). Each month I randomly choose one or more names from a list of people who either buy my software products or send me an e-mail asking to be entered (empty e-mails go to the trash bin). The name list starts fresh each month, so your entry only counts for the month it is received. Note: I have never sold, lent, traded, or given e-mail addresses to anyone for any reason.

3D Printing Key to

Hypersonic Weapons

3D Printing Key To Hypersonic Weapons: Raytheon  - RF Cafe"The race is on to build hypersonic weapons, missiles that blow through a target's defenses at more than five times the speed of sound. Or should that be 'the race to grow hypersonic weapons?' It turns out an unrelated cutting-edge technology, 3D printing, may be the key to making hypersonics work. The whole aerospace world is intrigued by so-called additive manufacturing - especially for government and/or unmanned applications not subject to laborious FAA safety testing on new technology. NASA has a 3D printer on the International Space Station; the Navy has tested one on a ship. Several rocket engine companies have built key components ..."

Free Engineering White Papers

Engineering White Papers & Books, April 2016 - RF CafeThe free whitepapers, pamphlets, books, magazines, and chapter examples listed here are a small sample of a lot of new items that are offered for FREE through TradePub. The publishers make them available to qualifying people as a promotional campaign for their full line of offerings. Note: I earn a few pennies (literally) when you download one of these or the many other pubs available, so please help yourself.

New Radio Antenna Avoids

Unwanted Signals

New Radio Antenna Avoids Unwanted Signals - RF Cafe"A new simpler, cheaper and potentially more effective way to prevent radio antennas from picking up unwanted signals has been created by researchers in the US. With further development, the technique could also be used to help prevent thermophotovoltaic cells from re-emitting radiation they absorb – according to the team. The laws of electromagnetism work exactly the same way if you run time in the opposite direction. One logical consequence of this is that an antenna designed to broadcast at a certain radio frequency will also be very good at absorbing radiation at that frequency. This is problematic for broadcast radio antennas, which ..."

Google Interview Questions

Google Interview Questions - RF CafeQuestions asked by interviewers at Google are objects of much ballyhoo. Depending on the job being sought, questions range from relatively simple and objective to massively esoteric and subjective. Perform a search on "Google Interview Questions" and you will find a host of websites that collect experiences from recent interviewees. Some people curse Google for their insanely difficult questions, but what is fundamentally a form of profiling and discrimination is what provides Google with exactly the employees they need to be at the leading edge of all sorts of technology - networking, software, hardware, publishing, website design, social media, global politics, search optimization, etc. As you can see, many questions require the interviewee to state assumptions and conditions prior to asserting a solution. For instance, "Estimate the number of tennis balls that can fit into a plane" has no single answer because while the size of a tennis ball ...

New Gravimeter-on-a-Chip is Tiny

Yet Extremely Sensitive

New Gravimeter-on-a-Chip is Tiny Yet Extremely Sensitive - RF Cafe"A tiny device that can make very precise measurements of the Earth's gravity has been unveiled by physicists at the University of Glasgow in the UK. While their gravimeter is not quite as sensitive as the best available sensors, the team says that it could be produced for a 1000th of the cost. It is also significantly smaller and lighter than current devices, and could be deployed in drone aircraft or in multi-sensor arrays to perform a range of tasks, including mineral exploration, civil engineering and monitoring volcanoes. Gravimeters are sensors that measure the local force ..."

Lawsuit Against Manufacturers Using

Leaded Solder Heads to Supreme Court

Class Action Lawsuit AgainstManufacturers Using Leaded Solder Headed for U.S. Supreme Court - RF CafeLyon Legal Justice Partners, a not for non-profit legal foundation based in Hill Valley, California, has announced in the wake of a crushing and unexpected loss before the United States 9th Circuit Court of appeals against manufacturers using leaded solder in their products, that his legal team will appeal the unprecedented 12.4 billion dollars awarded to class action members from its client companies that comprise the International Brotherhood of Electronics Assemblers. Plaintiffs originally sought 5 billion dollars as recompense for pain, suffering, lost wages, and lost opportunity by its class of more than 25,000 electronics manufacturing workers worldwide. 9th Circuit Court of Appeals Chief Judge M.R. Strickland; however, after finding defense counsel in contempt on multiple occasions during ...

RF Electronics Shapes, Stencils for Office, Visio by RF Cafe
Exodus Advanced Communications Best in Class RF Amplifier SSPAs
TotalTemp Technologies (Thermal Platforms) - RF Cafe
Innovative Power Products Passive RF Products - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free


About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024


    Kirt Blattenberger,


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

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: