Homepage Archive - January 2019 (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. About RF Cafe.

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Friday 11

Attack Planes Hug Hostile Terrain with New Radar

Attack Planes Hug Hostile Terrain with New Radar, February 21, 1964 Electronics Magazine - RF CafeAccording to this 1964 article in Electronics magazine, the U.S. Air Force's decision to build radar systems that would enable low altitude, terrain-following flight paths for strategic and tactical aircraft was in response to the shooting down of Gary Powers' U-2 spy craft in 1960. The event made clear that simply flying high over enemy territory and dropping bombs would not be a reliable strategy since surface-to-air missiles could reach and destroy aircraft before they got to their targets. Terrain-following capability on the part of bombers and fighters would add a major element of surprise since approach paths could be masked until it was too late to take offensive action. That approach was not without its risks and faults, as made apparent by the Dr. Strangelove movie satire that poked fun at the very concept ...

R&S EMC Resources for Emissions and Immunity Testing

Rohde & Schwarz EMC Resources for Emissions and Immunity Testing - RF CafeEvery month Rohde & Schwarz USA puts together a few resources intended to help you tackle your latest EMC test challenge. This month, we focus on two very different topics. "The value of pre-selection in EMC Measurements" which is an often misunderstood or underestimated concept, and "Going Beyond the Basics to Ensure Successful Immunity Tests" which covers the ins and outs of what to look for when working with and selecting an EMC amplifier. The "EMC Amplifiers – Going Beyond the Basics to Ensure Successful Immunity Tests" webinar focuses on the basics and intricacies of immunity testing, a technical overview of EMC amplifiers ...

Saelig Intros VSG6G1C USB 6 GHz RF Vector Signal Generator

Saelig Introduces VSG6G1C USB 6 GHz RF Vector Signal Generator - RF CafeSaelig Company announces the availability of Triarchy Technologies' VSG6G1C RF Vector Signal Generator - a cost-effective pocketable USB-connected RF signal source with capabilities that provide standalone and PC-controlled functions comparable to full-size analog RF signal generators. Offering frequencies from 1 MHz to 6.1 GHz with frequency sweep, frequency hopping using I&Q modulation, and arbitrary signal generation, this compact signal source can generate most of the modulated signals that RF engineers might need. The VSG6G1C's many test functions can be customized to meet the needs of proprietary and other nonstandard wireless protocols. This compact design is ideal for field test situations since it can be conveniently added to a field service kit, and configured to operate standalone ...

War and the Radio Amateur

War and the Radio Amateur, May 1917 The Electrical Experimenter - RF CafeAmateur radio station operators seemed to always be amongst the first to lose their rights in time of war. Governmental power brokers - from unelected local bureaucrats on up to presidents - love to demonstrate their influence over citizens when the opportunity arises. The Radio Act of 1912 revoked the rights of amateur radio stations to operate, and in some cases authorized the confiscation of radio equipment for use by the government. Permission was not restored until 1919, after World War I. Amateurs took it on the chin again in World War II with revocation of licenses. In this 1917 article in The Electrical Experimenter publisher Hugo Gernsback makes the case for permitting "our red-blooded boys be trusted to assist our officials in running down spies." "...we realize how absurd it is to close all privately owned radio stations during the war ..."

2019 Forecast: Hard Choices on Invisible Electronic Warfare

2019 Forecast: Hard Choices on Invisible Electronic Warfare - RF Cafe"There are real signs of a renaissance in electronic warfare. Now comes the hard part: translating new strategies and concepts into doctrine, requirements, and systems in the field. After a quarter-century of post-Cold War neglect, the Department of Defense has once again become serious about electronic warfare: the art of detecting, disrupting, and deceiving enemy radio and radar. But battles between electrons are invisible, literally and often politically as well, and EW must fight for attention and resources with higher-profile efforts from hypersonic missiles and missile defense to combat readiness for everything from fighter jets to nuclear submarines ..."

Rohde & Schwarz USA: RF & Microwave, Analog, Digital, & Optical Test Equipment

Rohde & Schwarz USA Pocket Guides - RF CafeRohde & Schwarz develops, produces and markets test & measurement, information and communications technology. Focus is on test and measurement, broadcast and media, cybersecurity, secure communications, monitoring and network testing. Markets serviced are wireless, the automotive industry, aerospace and defense, industrial electronics, research and education, broadcast and media network operations, consumer electronics, cybersecurity for business and governments, communications and security solutions for critical infrastructures and the armed forces, reconnaissance equipment for homeland and external security, and much more ...

Thursday 10

Mac's Service Shop: Radio Interference

Mac's Service Shop: Radio Interference, January 1972 Popular Electronics - RF CafeAlthough published in a 1972 issue of Popular Electronics magazine, the topic of dealing with radio interference is timeless. Some of the sources of radio interference change over the years, but there is always a need to discover and resolve such problems, and more importantly, use the lessons learned to attempt to prevent it in the first place. The January setting in the Great Lake Midwest region of the U.S. is right on time for when this is being posted. It's snowing here in Erie, Pennsylvania, as I write this, the temperature is about 24°F, and the wind is howling at 15-20 miles per hour as is has been all night. "Someone must have sprayed circuit-cooler around out there," Barney (Mac's able young assistant) complained. "Man, it's cold!" That about sums up today's weather. Unfortunately for Barney, he would be called upon to leave the warmth of the shop to make a service call to figure out why CB radio transmissions ...

RF and Digital Hardware Designer Engineer Wanted by Nokomis

RF and Digital Hardware Designer Engineer (Nokomis) - RF CafeNokomis, the preeminent company in the world in the detection, identification, and geolocation of electronics, currently has an opening for an Electrical Engineer / RF and Digital Hardware Designer. Nokomis is actively seeking candidates for a number of positions including PhD and MS level electrical engineers, physicists, computer scientists as well as administrative, management and sales positions. Responsibilities include: Design hardware to suit given requirements and document the design, Electromagnetic or SPICE circuit simulation a plus, Circuit design of RF, Digital, mixed-signal and analog circuits, Test, debug and evaluation of PCB assemblies, Embedded software or FPGA experience a plus ...

Triad RF Systems Displays Space Flight Heritage with S-Band CubeSat Amplifier

Triad RF Systems Displays Space Flight Heritage with S-Band CubeSat Amplifier - RF CafeTriad RF Systems, a top-tier designer and manufacturer of RF and microwave amplifiers, has received confirmation of the successful field operation of the TA1109, which is currently aboard a CubeSat chassis flying in Low Earth Orbit (LEO). The TA1109 operates from 2000 to 2500 MHz and provides 4 watts of output power, ensuring proper and consistent communication at distances in excess of 2000 km or 1200 miles. Weighing less than an ounce and smaller than a credit card, the TA1109 is ideal for even the smallest CubeSat systems. This amplifier uses a circuit card form factor, making it integrate easily into a wide array of custom CubeSat communication systems ...

Put a Charge into Your Battery Testing

Put a Charge into Your Battery Testing (Axiom Test Equipment) - RF CafeAxiom Test Equipment, a premier provider of electronic test and measurement equipment rentals and sales, has a new blog post you might find useful titled, "Put a Charge into Your Battery Testing." Batteries provide power for portable electronic devices. They come in many shapes and sizes, from tiny cells that power pocket-sized personal electronic devices to large, fixed systems. They are also available in different chemistries, such as alkaline, lead-acid, and lithium-ion cells. Each battery chemistry results in battery cells with different voltages, such as 1.5 V for alkaline cells, 2.0 V for lead-acid cells, and 3.0 V for lithium cells. Commercial batteries are typically comprised of multiple connected cells to achieve higher voltages, such as 12 or 24 V. Batteries are obviously essential components in any portable electronic product ...

Bilectro "One Hander" Soldering Tool

Bilectro "One Hander" Soldering Tool, January 1972 Popular Electronics - RF CafeIt seemed like a reasonable idea, but the absence of "One Hander" soldering tools on the market today - or any time in the last half century for that matter - is empirical proof that the concept is not feasible. In principle, being able to feed the solder into the joint area with a squeezable pistol grip setup is not so different than modern wire welding machines that basically do the same thing (I have one). It was probably the lack of stiffness of the solder wire that caused the problem since keeping it on the joint would be difficult. Preventing the flux from jamming the solder feed tube was no doubt an issue as well. Oh well, it was worth a try. Today's surface mounted components could never be soldered with such a device, even if modernized to accommodate the smaller sizes ...

NEC Real-Time Digital OAM Multiplexing Transmission at 80 GHz

NEC Real-Time Digital OAM Multiplexing Transmission at 80 GHz - RF Cafe"NEC Corporation has successfully demonstrated real-time digital wireless Orbital Angular Momentum (OAM) mode multiplexing transmission over 40 meters in the 80 GHz-band. This technology can help solve the ever-increasing demand for high-capacity wireless connections for 5G networks. NEC aims to use this technology for its iPASOLINK series of ultra-compact microwave and mmWave communication products, which are capable of extremely reliable, high-capacity mobile backhaul solutions for 5G networks. In recent years, more and more base stations are required for proper transmission coverage, especially in hot spots and ultra-dense urban areas, where the cell grid becomes very dense. Additionally, datacenters will be moving to the edge ..."

everythingRF: Their Name Says It All

everything RF Searchable Database - RF CafePlease take a few moments to visit the everythingRF website to see how they can assist you with your project. everythingRF is a product discovery platform for RF and microwave products and services. They currently have 227,460 products from more than 1210 companies across 285 categories in their database and enable engineers to search for them using their customized parametric search tool. Amplifiers, test equipment, power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers, power supplies, and everything else. Please visit everythingRF today to see how they can help you ...

Wednesday 9

Anatech Electronics Early January Product Update

Anatech Electronics Product Update January 4, 2019 - RF CafeAnatech Electronics 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: connectorized 763−768 MHz / 793−798 MHz single in/out duplexer, a connectorized 1090 MHz cavity bandpass filter, and a surface mount 836.5 MHz / 881.5 MHz SAW duplexer. Custom RF filters designs are used when a standard cannot be found, or the requirements are such that a custom approach is necessary ...

How Much Current Is Fatal?

How Much Current Is Fatal?, January 1972 Popular Electronics - RF CafeThose of us who have been working for a long time around electricity with exposed circuit components are well aware that as little as one-tenth of an ampere (1/10 A) can produce a lethal reaction, particularly if the current path runs through the heart (i.e., hand-to-hand). Some of us (moi) have even experienced a pretty significant jolt from a high voltage vacuum tube power supply and/or from a 480 volt, three-phase supply to an industrial motor. Fortunately, the worst damage done was to my ego and a feeling of utter stupidity for allowing the occurrence to happen. If you are new to the concept of electrocution, you might be inclined to wonder why, when the chart below shows certain current levels with corresponding effects, would I mention exposure to high voltages? The answer is that various current paths through your body ...

Keysight Delivers Professional Functionality in Entry-Level O-scope

Keysight Technologies Delivers Professional Functionality in Entry-Level Oscilloscope - RF CafeKeysight Technologies, a leading technology company that helps enterprises, service providers, and governments accelerate innovation to connect and secure the world, today announced the 200 MHz, 4-channel models of the InfiniiVision 1000 X-Series oscilloscopes, providing professional-level measurements and capabilities at an affordable price, including 4-wire Serial Peripheral Interface (SPI) decode and remote connection via local area networks (LANs). The new InfiniiVision 1000 X-Series oscilloscopes use the same user interface and measurement technology found in the higher performance Keysight InfiniiVision oscilloscopes. The intuitive front panel ...

AVX Thin-Film Transmission Line Capacitors

AVX Thin-Film Transmission Line Capacitors - RF Cafe"AVX Corporation has introduced a new line of ultraminiature, thin-film transmission line capacitors for high-frequency links, DC blocking in the UHF range (300 MHz – 3 GHz), and other high-performance microwave and RF applications. The new capacitors have a novel metal-insulator-metal (MIM) structure, copper traces for optimal circuit conductivity, a transmission line wire-bond pad, and a gold-metallized backside ground, and can be supplied on a variety of low-loss substrates, including quartz, alumina, glass, and silicon. The new transmission line capacitors are also available in a wide range of capacitance values: 0.3-50 pF with a ±20% tolerance, and each is made using a high-frequency structure simulator (HFSS) to proactively address any electromagnetic ..."

Energy Frequency Chart - Where Do You Resonate?

Energy Frequency Chart - RF CafeAn RF Cafe visitor and who wishes to remain anonymous (Engineer−X) sent me this "Energy Frequency Chart" that purports to have identified "average frequencies of some of the therapeutic grade essential oils that have been measured." That's right, you probably didn't know that your body parts have specific frequencies at which when resonance is achieved, healing powers are realized. This claim must be true because it is on the Internet. The purveyor of these magical, essential oils has had results verified by Eastern Washington University by using a Calibrated Frequency Monitor (CFM). Surely you have a CFM in your test lab. Engineer−X dutifully notes that many of the essential oils resonates in the FM radio and aviation communications bands as well as at Part 15 key fob frequencies, which must explain why you feel good in their presence. Count me amongst the skeptics and "Essential Oils Deniers." The sad fact is many people buy into (literally) this malarkey.

Swarm Wants to Send Hundreds of Tiny CubeSats into Orbit

Swarm Wants to Send Hundreds of Tiny CubeSats into Orbit - RF Cafe"A day after being whacked with a US $900,000 FCC fine for launching four tiny CubeSats without permission, Silicon Valley startup Swarm Technologies sought permission for dozens more of its controversial small satellites, according to documents obtained by IEEE Spectrum. Swarm wants to create an orbital network of miniature satellites that will offer a global Internet of Things communication service at a fraction of the price of existing systems. 'Swarm will offer two-way communications services to allow end users to send and receive data anywhere in the world,' reads its latest FCC application. 'The Swarm constellation will be deployed rapidly, and begin to offer commercial services even prior to full deployment of the constellation ..."

QuinStar Technology: mm-Wave Active & Passive Components

QuinStar Technology mm-Wave Products - RF CafeQuinStar Technology designs and manufactures mm-wave products for communication, scientific, and test applications along with providing microelectronic assembly, rapid prototyping, and mass customization. Amplifiers, Oscillators, Switches, Attenuators, Circulators, Isolators, Filters, Waveguide, Antennas, Phase Shifters, Transceivers, Mixers, Detectors. QuinStar specializes in cryogenic amplifiers, circulators, and isolators. Please visit QuinStar today to see how they can help your project ...

Tuesday 8

Antenova 'Raptor' SMD Antenna Can Pinpoint Location to Within Centimeters

Antenova 'Raptor' SMD Antenna Can Pinpoint a Location to Within Centimeters - RF CafeAntenova Ltd, manufacturer of antennas and RF antenna modules for M2M and the Internet of Things, has developed a new SMD positioning antenna that achieves an extraordinary level of accuracy in the GNSS bands – it can pinpoint a location to within centimetres. The Raptor antenna utilises the L2, 1200 MHz satellite bands which recently became available for civilian use. It is the latest addition to Antenova's lamiiANT range of rigid FR4 antennas which are designed for easy insertion onto a PCB. The antenna itself is very small - it is a GPS single feed antenna in SMD form, measuring just 16.0 x 8.0 x 1.6 mm, which makes it suitable for small PCBs within all kinds of small electronic devices. "This is an outstanding antenna, because it achieves the same precision ..."

QuinStar Technology Engineer Captures Orion Nebula

QuinStar Technology Engineer Captures Orion Nebula - RF CafeAt QuinStar, we're about more than millimeter-wave technology. The people comprising QuinStar Technology pursue diverse and exciting outside interests. Our Chief Engineer, Jim Schellenberg, is a highly skilled amateur astronomical photographer. He captured this beautiful image of the Orion nebula using a specially modified Canon 6D. The camera responds to the H-alpha spectral line at 656 nm (from hydrogen gas), which is seen as red in the photo. The camera is mounted on an 11-inch telescope that tracks the object as the earth rotates. This image consists of nine one-minute exposures that are "stacked" to form the image you see. This is an excellent time of the year to view the Orion nebula. It can be seen with the naked eye ...

Comics with an Electronics Theme

Comics with an Electronics Theme, May 1967 Popular Electronics - RF CafeWalt Miller drew a lot of comics for electronics magazines like Popular Electronics, and he did the cover art for Astounding Science Fiction magazine. No doubt there were others. I could not find any detailed information about Mr. Miller's personal background, such as whether he was a Ham radio operator, but clearly he enjoyed electronics and science topics. This group of comics, which appeared in the May 1967 issue of Popular Electronics, touches on many scenarios that would have been familiar to hobbyists of the day. I like the one where the guy sneezes and scatters carefully counted and sorted resistors all over the floor. Another refers to installment plans for purchasing equipment. That was from a time when credit cards were not handed out like candy and only people with provable credit-worthiness could get them ...

Thermal Testing with Convection and Conduction… Together at Last!

Thermal Testing with Convection and Conduction… Together at Last! - RF CafeEngineers at TotalTemp Technologies have published a white paper titled, "Thermal Testing with Convection and Conduction… Together at Last!" It begins: "A heartfelt Congratulation is in order for the happy and successful union of two distinct thermal testing methods that are finally sharing the same dance floor together – as the first true Hybrid. To better understand the specific benefits from both sides of this collaboration of two testing methods, please review of the following white paper. Thermal testing by conduction is most commonly done on a Thermal Platform. Platforms control temperature by conductive heat ..."

New San Francisco Circuits Components Cheat Sheet

New San Francisco Circuits Components Cheat Sheet - RF CafeSan Francisco Components (SFC) has introduced a new educational component of its website to address Printed Circuit Board (PCB) component sourcing and overages. The information is geared to help customers source the right amount of critical components without creating costly shortages during PCB assembly. The component overages worksheet gives target quantities for projects based on the number of finished pieces required. The sheet is broken down by component size for common resistors and capacitors. SFC also offers a formula for more expensive parts for more accurate budgeting. "One of the most frequent questions we get from customers is how to know what is the right quantity of components that are needed for any given project ...

Competing State of Matter in Superconducting Material

Competing State of Matter in Superconducting Material - RF Cafe"A team of experimentalists at the U.S. Department of Energy's Ames Laboratory and theoreticians at University of Alabama Birmingham discovered a remarkably long-lived new state of matter in an iron pnictide superconductor, which reveals a laser-induced formation of collective behaviors that compete with superconductivity. 'Superconductivity is a strange state of matter, in which the pairing of electrons makes them move faster,' said Jigang Wang, Ames Laboratory physicist and Iowa State University professor. 'One of the big problems we are trying to solve is how different states in a material compete ..."

Monday 7

R&S White Paper: Radio Fundamentals for Cellular Networks

Radio Fundamentals for Cellular Networks - RF CafeWhether you are new to working in the cellular communications realm or are just interested in learning more about the system about which the world turns today, this free "Radio Fundamentals for Cellular Networks" white paper by Rohde & Schwarz will be useful to you. "Cellular technologies have advanced from first generation (1G) analog technologies to advanced high- performance fourth generation (4G) and fifth generation (5G) systems in just four decades. Despite the increase in complexity of wireless standards and devices, cellular technologies maintain a set of common principles that form the basis behind the design of cellular systems. In this white paper, we explore these basic principles and examine the underlying technologies that lay the foundation for today and future cellular systems ..."

Electromotive Force (EMF): What It Is

Electricity - Basic Navy Training Courses, NAVPERS 10622, Chapter 5 - EMF (Electromotive Force) - RF CafeChapter 5 of the U.S. Navy's basic electronics course of study, titled "EMF: What It Is," introduces the concept of electromotive force. It follows lessons on electric current and static electricity where students learned that potential difference causes electrons to flow through a conductor. But - you'll have to know about another "electron-mover." Because it is an "electron-moving-force," scientists have named it Electromotive Force (emf). Mechanical force is usually measured in pounds, but emf is measured in volts. Just as pounds of force make water flow through a pipe, so emf makes current flow through a conductor. The three terms - potential difference, electromotive force, and voltage - are often used interchangeably. You will hear electricians say, "Voltage of the generator"; or "EMF of the generator" and "Voltage of the circuit" or "Potential of the circuit ...

Thanks Once Again to everythingRF for Long-Time Support!

everything RF Searchable Database - RF CafePlease take a few moments to visit the everythingRF website to see how they can assist you with your project. everythingRF is a product discovery platform for RF and microwave products and services. They currently have 228,567 products from more than 1222 companies across 291 categories in their database and enable engineers to search for them using their customized parametric search tool. Amplifiers, test equipment, power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers, power supplies, and everything else. Please visit everythingRF today to see how they can help you ...

R&S White Paper: An Introduction to EMC Amplifiers

R&S White Paper: An Introduction to EMC Amplifiers - RF CafeFree for your downloading pleasure is Rohde & Schwarz's white paper titled, "An Introduction to EMC Amplifiers." "In order to perform immunity testing on an electronic device, we must subject that device to defined levels of radio frequency energy over a wide range of frequencies and verify that the device continues to function properly. This radio frequency energy may be conducted into a device via its attached cables or be directly picked up 'over - the - air,' i.e. from radiated signals. As we will see, radiated emissions represent the greater challenge in immunity testing. The first reason for this is that radiated immunity (or susceptibility) testing often requires the creation of very high electric field strengths , with typical values ranging from 3-200 V/m. Depending on frequency, distance ..."

Novel Front-End Rejects RF Self-Interference for LTE

Novel Front-End Rejects RF Self-Interference for LTE - RF Cafe"U-blox and University of Bristol have developed a tunable frequency-division duplexing RF front-end that combines passive and active self-interference cancellation. With the proof-of-concept demonstrator, an electrical-balance duplexer is used to passively cancel transmitter noise in the receive band, and an active canceller is employed to suppress self-interference in the transmit band. It has been characterized in duplex configurations working between 700 MHz and 950 MHz, as well as LTE bands 3 (1.9 GHz) and 7 (2.6 GHz). Noise figure is 6.0-7.4 dB in the presence of a +27 dBm LTE uplink Tx blocker for duplex separations of 47.5 MHz and above ..."

Lotus Communications Systems: Modularized RF System Components

Lotus Communication SystemsLotus Communication Systems is a supplier of high performance connectorized RF modular system components, shielded project cases, and special purpose solutions up through 40 GHz. Lotus is a privately owned company with mechanical and electronic design, manufacture, test controlled from its Middlesex, MA, facility. They have multiple 4 axis CNC machines and LPKF circuit plotters. Lotus can provide custom extension of our standard products, custom designs for specific applications and prototyping for your new products ...

Sunday 6

RF Cafe Engineering & Science Crossword Puzzle for January 6

RF Cafe Engineering & Science Crossword Puzzle January 6, 2019Each week, for the sake of all avid cruciverbalists amongst us, I create a new technology-themed crossword puzzle using only words from my custom-created lexicon related 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 Lamarr or the Bikini Atoll, respectively. Enjoy ...