Homepage Archive - February 2019 (page 4)

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Friday 1

Chemicals for Electronics

Chemicals for Electronics, April 1971 Popular Electronics - RF CafeFreon has for so long been demonized as a destroyer of the ozone layer and has so thoroughly disappeared from consumer grade products that I had forgotten that many moons ago I and others used it on a regular basis for cleaning electronics assemblies. Freon 12, methyl chloroform (aka 1,1,1-Trichloroethane ), and methyl ethyl keytone (MEK, aka butanone) were all very common cleaners for removing contaminants prior to soldering and for removing flux after soldering in the days of 60/40 Sn/Pb solder and RMA (rosin, mildly activated) flux. Call me a heretic of the green movement, but I still use 60/40 rosin core solder for all my electronics work. In fact, I just ordered a new 1-pound roll of it from Kester, along with a bottle of liquid RMA flux. I have changed over to Pb-free solder for plumbing, although I'm still a bit nervous when using it - especially when soldering into installed pipes that have been plugged with a piece of bread to (hopefully) keep the area dry long enough to sweat a good joint ...

Thanks to VidaRF for Many Years of Supporting RF Cafe!

vidaRF passive RF & microwave components - RF CafeAt VidaRF, the phrase 'Providing Simple Solutions for Complex Connections' is more than just a slogan – it's a mindset, a mission, and a driving force behind everything we do. Their pledge is to design and distribute high performance, cost effective RF Microwave products to fit each customer's unique applications. Please visit VidaRF today to see how their lines of Attenuators & Terminations, Directional Couplers, Power Dividers, Coaxial Connectors, and Circulator & Isolators can be of use to your project. "When the standard just will not do, VidaRF has the solution for you!" ...

Electronic Sticklers

Electronic Sticklers, April 1959 Popular Electronics - RF CafeHere is another of the "Electronic Sticklers" challenges from Popular Electronics magazine - good for ratcheting down at the end of the week. These are fairly basic circuit analysis problems that often can be solved by inspection, but sometimes a pencil and paper are necessary. Re-drawing the circuit in a different configuration to make the connections more obvious often helps when solving total resistance, capacitance, inductance, etc., as in question #1. In this case, though, you need to be able to recognize a common configuration to be able to simplify the circuit; otherwise, you'll be writing and solving mesh equations. #2 has a simple answer and a more elaborate possibility. #3 and #4 are simple inspection problems ...

Empower RF Intros 600-6000 MHz, 30W, GaN Module

Empower RF Systems Intros a 600-6000 MHz, 30W, GaN Module - RF CafeEmpower RF is pleased to announce the release of Model 1219, a single band solid state GaN module delivering a minimum 30 W (40 W typical) across its entire 0.6 to 6 GHz band. Empower RF is the first amplifier manufacturer to cover this bandwidth with an affordable COTS product. The 1219 utilizes 50 V GaN on SiC transistors which have lower leakage currents and higher thermal conductivity and is a more reliable technology than GaN on Si. An added benefit, 50 V devices require about half the input current as their 28 V counterparts which reduces power supply cost, size, and weight. This compact class AB amplifier is suitable for broadband mobile communications, jamming, and product test applications ...

Algorithms to Antenna: Calibration Techniques for Phased-Array Antennas

Algorithms to Antenna: Calibration Techniques for Phased-Array Antennas - RF CafeMssrs. Rick Gentile of MathWorks (MATLAB & Simulink), Honglei Chen, and Marc Willerton have nice article on the Microwaves & RF website titled, "Algorithms to Antenna: Calibration Techniques for Phased-Array Antennas." This post discusses calibration for perturbed phased-array antennas, examining techniques like pilot calibration and self-calibration. "When large phased-array antennas are built, perturbations in amplitude, phase, element position, and antenna patterns will invariably be present due to a range of factors. Perturbations can also arise due to other factors, such as coupling, hardware aging, clock drifting, and environmental effects. These perturbations may impact the performance of the system ..."

Please Welcome Custom MMIC as an RF Cafe Sponsor!

Custom MMIC - RF CafeCustom MMIC is a fabless RF and microwave MMIC designer entrusted by government and defense industry OEMs. Custom and off-the-shelf products include switches, phase shifters, attenuators, mixers and multipliers, and low noise, low phase noise, and distributed amplifiers. From next-generation long range military radar systems, to advanced aerospace and space-qualified satellite communications, microwave signal chains are being pushed to new limits - and no one understands this more than Custom MMIC. Please contact Custom MMIC today to see how they can help your project ...

Sub-THz Wavelength Detection System Helps Autonomous Cars See

Sub-Terahertz Wavelength Detection System to Help Autonomous Cars See through Dust and Fog - RF Cafe"Researchers at MIT have developed a sub-terahertz-radiation receiving system that could help steer driverless cars when traditional methods fail. Currently, autonomous vehicles traditionally, use light-based image sensors that often struggle to see through blinding conditions, such as fog. Sub-terahertz wavelengths, which are between microwave and infrared radiation on the electromagnetic spectrum, can be detected through fog and dust clouds with ease, whereas the infrared-based Lidar imaging systems used in autonomous vehicles struggle. To detect objects, a sub-terahertz imaging system sends an initial signal through a transmitter; a receiver then measures the absorption and reflection of the rebounding ..."

ERZIA: Microwave & mm-Wave Modular Amplifiers

Many Thanks to ERZIA for Continued Support!ERZIA serves critical aerospace and defense missions by designing and manufacturing RF, microwave, and mm-wave amplifiers, integrated assemblies operating from low frequencies up to 100 GHz, and by providing high reliable satellite communications. The company was founded in 2002 to become a worldwide reference of advanced engineering, performance, reliability and ruggedness. 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 ...

Thursday 28

Artificial Delay Lines

Artificial Delay Lines, March 1953 Radio-Electronics - RF CafeThere are probably few baseband and IF delay lines these days that are constructed from a chain of inductor-capacitor (LC) sections as described in this 1953 Radio-Electronics magazine article. SAW and MEMS devices are the more likely choice for many reasons including cost, weight, and volume savings. The preferred implementation of measured delays nowadays would be in software after sampling with an analog-to-digital converter (ADC). There are still applications for coaxial delay lines such as phase matching or adjustment between system elements, and many companies offer custom designs with delay precision in the tens of picoseconds. I once worked on part of a VHF/UFH transceiver unit that used precise lengths of coax cable as part of a signal cancellation circuit for enabling multiple radios to function in close proximity. I was not the designer ...

KP Performance Antennas Debuts New 900 MHz Omni Antenna

KP Performance Antennas Debuts New 900 MHz Omni Antenna Boasting 10 dBi of Gain & Dual Polarization - RF CafeKP Performance Antennas, an Infinite Electronics brand, and an industry-leading manufacturer of wireless network antennas, has unveiled a brand new 900 MHz, 10 dBi, ±45° slant dual-polarized omni antenna for use in outdoor fixed wireless applications. This new omni-directional antenna from KP operates in the 824-928 MHz frequency range and provides uniform, 360° coverage with minimal azimuth ripple and 10 dBi of gain. It supports any 900 MHz access point radio (AP), including the popular Cambium® PMP450i™ radio for point-to-multipoint installations. This new 900 MHz omni antenna has 15° elevation beamwidth and is able to penetrate dense foliage with 900 MHz, dual ±45° slant polarization. The antenna comes with robust mounting hardware ...

Vintage Bliley Electric Advertisement

Bliley Electric and Gross Radio Advertisements, July 1935 QST - RF CafeThese two advertisements appeared in the July 1935 edition of QST. Bliley Electric is still in business here in Erie, Pennsylvania as Bliley Technologies. They make crystals and frequency sources. Gross Radio has been out of business for quite a while. I included it mainly to illustrated how large radio transmitters used to be - these things were installed in people's attics and basements back in the day. This particular model, the CB-100, is a "100-Watt Radiophone & C.W. Transmitter completely housed in an entirely enclosed floor rack of ingenious design." It operated in the 1.7, 3.5, 7 and 14 MHz bands. For comparison, iCOM makes a 1 kW power amplifier today covering those bands ...

Meta Surfaces Steer RF, Light or Sound Arbitrarily

Meta Surfaces Steer RF, Light or Sound Arbitrarily - RF Cafe"Meta surfaces can be designed to steer sound or electromagnetic waves in arbitrary directions, or act as beam splitters, according a team from Aalto University in Finland and Duke University North Carolina. 'Existing solutions for controlling reflection of waves have low efficiency or difficult implementation,' said Aalto researcher Dr Ana Díaz-Rubio. 'We solved both of those problems. Not only did we figure out a way to design high efficient meta-surfaces, we can also adapt the design for different functionalities. These meta-surfaces are a versatile platform for arbitrary control of reflection.' The surfaces have been dubbed meta-mirrors, and the key to creating them is applying new physics ..."

CMT Dielectric Property Measurements Webinar

Copper Mountain Dielectric Property Measurements Webinar - RF CafeCopper Mountain Technologies (CMT), along with Compass Technology Group, has a webinar titled "A New Method for Dielectric Property Measurements" coming up on Thursday, February 28, at 11:00 am EST. Dr. Schultz, Chief Scientist at the Compass Technology Group, is the presenter. Dielectric properties are important for design of antenna and wireless technologies. As the internet of things, 5G, automotive sensing, and other advanced technologies become more prevalent, product designers and manufacturers require accurate material properties for ensuring their devices operate as desired. This webinar will provide information about dielectric materials measurements and introduces a new dielectric measurement method, called the epsilometer ...

Triad RF Systems: RF/Microwave Amplifiers and Amplifier Systems

Triad RF SystemsTriad RF Systems designs and manufactures RF power amplifiers and systems. Triad RF Systems comprises three partners (hence 'Triad') with over 40 years of accumulated knowledge of what is required to design, manufacture, market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA, bi-directional, and frequency translating amplifiers are available, in formats including tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology partner than a vendor for our line-of-sight communications product line." Please check to see how they can help your project ...

Wednesday 27

Battle of the Giant Brains or Electronics Conquers All

Battle of the Giant Brains or Electronics Conquers All, April 1971 Popular Electronics - RF CafeAlbert Einstein declared and proved that time is relative and depends on the observer's perspective. To someone sixty years old, the year 1971 seems like it was just yesterday, but to people born a couple decades ago, it seems like ancient history. Even so, I am taken by surprise when I read a story from a 1971 issue of Popular Electronics that has produced a list of "early computers" and it includes models like the ENIAC and Harvard Mark I. Instinctively, the IBM XT, Apple II, and Packard Bell, and Compaq lines of personal computers (PCs) come to mind. In 1971, there were no PCs. However, if you compile a list of antique computers, then the aforementioned names apply. This article does provide a nice recounting of the evolution of digital computers from Charles Babbage's mechanical Difference Engine through those vacuum tube-based electronic computers ...

NI AWR Software E-Learning Portal Adds RF PCB Import Wizard Module

NI AWR Software E-Learning Portal Adds RF PCB Import Wizard Module - RF CafeA new e-learning module covering the NI AWR Design Environment platform RF printed circuit board (PCB) layout import wizard technology is now available on the NI AWR e-learning portal. This seven-part module, running approximately one hour, trains users on how to use the PCB layout import wizard for successful electromagnetic (EM) verification within Microwave Office circuit design software. It covers verification flows and layout file formats supported, and showcases a Zuken PCB design example through material, port and mesh setup, as well as simulation ...

The Operational Amplifier

The Operational Amplifier, August 1967 Electronics World - RF CafeThere is no such thing as too many introductory articles on operational amplifiers (opamps). Of course, when this story was written for Electronics World back in 1967, opamps were relatively new to the scene. Prior to the advent of opamps, circuit design for controllers, filter, comparators, isolators, and just plain old amplification was much more involved. Opamps suddenly allowed designers to not worry as much about biasing, variations in power supply voltages, and other annoyances, and instead focus on function. Even from the very beginning with the μa741 operational amplifier, the parameters came close to those of an ideal device: infinite input impedance, zero output impedance, perfect isolation between ports, and infinite bandwidth. OK, the bandwidth spec was more constrained compared to the other three, but still, with frequencies ...

ConductRF Phase & Temperature Stable Cables

ConductRF Phase & Temperature Stable Cables February 2019 - RF CafeConductRF is the brand name for Electronic Assemblies Manufacturing, Inc.'s, complete range of RF interconnect products. ConductRF products include solutions for both commercial and precision RF applications for both RF cable assemblies and connectors. Our manufacturing capabilities include solutions built at our ITAR registered facility in Methuen as well as partner facilities in the U.S. and around the world. ConductRF offers cost effective equivalent and improved RF solutions to all major interconnect manufacturers, specializing in phase stability over temperature ...

Friendly Electromagnetic Pulse Improves Survival for Electronics

Friendly Electromagnetic Pulse Improves Survival for Electronics - RF Cafe"An electromagnetic pulse (EMP) emitted by a nuclear weapon exploded high above the United States could disable the electronic circuits of many devices vital to military defense and modern living. These could include complicated weapon systems as well as phones, laptops, credit cards and car computers. Also in trouble might be home appliances, gas station pumps and bank accounts. Fortunately, military equipment is designed to be immune to various levels of EMP, and the validity of its designs - and some civilian designs as well - have been tested and improved by a 'friendly' EMP generator installed in a recently renovated facility at Sandia National Laboratories ..."

RF & Connector Technology: Coax Connectors, Cable, Passive Components

RF & Connector Technology - RF CafeProviding full solution service is our motto, not just selling goods. RF & Connector Technology has persistently pursued a management policy stressing quality assurance system and technological advancement. From your very first contact, you will be supported by competent RF specialists; all of them have several years of field experience in this industry allowing them to suggest a fundamental solution and troubleshooting approach. Coaxial RF connectors, cable assemblies, antennas, terminations, attenuators, couplers, dividers, and more. Practically, we put priority on process inspection at each step of workflow as well as during final inspection in order to actualize "Zero Defects ..."

Tuesday 26

New Magnetron Shifts Frequency Fast

New Magnetron Shifts Frequency Fast, April 6, 1964 Electronics Magazine - RF CafeFrequency hopping spread spectrum, first proposed and patented by Hollywood actress Hedy Lamarr, relies on both transmitters and receivers to precisely tune in a pseudorandom manner to a band of discrete frequencies in a time-synchronized manner with each other. The faster an encoded signal hops between frequencies, the more difficult it is for an unintended listener to decode the message. Same goes for the number of discrete frequencies used in the spread spectrum scheme. Modern computer programs and fast-tuning receiver systems can gather huge amounts of information spread across a broad bandwidth and re-assemble it into intelligible data, and if an unlimited amount of time was available to do so, just about any message can be decoded ...

VidaRF Intros Broadband Power Dividers for 698 MHz to2.70 GHz

VidaRF Intros Broadband Power Dividers for 698 MHz to2.70 GHz - RF CafeVidaRF, a manufacturer of high performance RF and microwave high performance isolators, circulators, power dividers, couplers, and other passive components, is proud to introduce VidaRF introduces Power Dividers covering 698 MHz through 2.70 GHz for all wireless applications from cellular through UMTS. Available in 2, 3, 4, 6 and 8-way with SMA, N, QMA or alternative connector configurations. VidaRF is focused on being a solution provider by building to customer specs and offering zero days lead time for custom parts through stock and ship program ...

How to Use Your Radio

How to Use Your Radio, April 1934 Tower Radio Magazine - RF CafeThis 1934 edition of Tower Radio magazine was thrown in with a batch of vintage radio magazines I bought on eBay. Most of the content pertains to entertainers of the day rather than with technical issues. Reportedly, it was only sold at Woolworth's stores. Ironically, the number of households with over-the-air (OTA) radio listeners today, at least as a percentage of the population if not in absolute numbers, is probably about the same as in 1934 when commercial radio broadcasting was just getting a foothold. These days, many - if not most - people listen to radio and podcasts via cellphone and/or Internet streaming media than from over-the-air broadcasts, even while in their cars. Organizations like the National Association of Broadcasters (NAB) are trying to change that, but it's an uphill battle. I tune in to OTA when possible, but with my radio sitting close to the computer with all the EMI it spews ...

1 to the 4th Power Amplification in Star Trek Redux

1 to the 4th Power Amplification in Star Trek Episode - RF CafeA few years ago I posted a note about a technical faux pas on an episode of Star Trek titled "Court Martial," where Captain Kirk makes a comment ordering the ship's auditory sensors to be boosted "on the order of 1 to the 4th power," (14) in order to pick up heart beats. RF Cafe visitor Sam M. just sent me a note offering a possible - and plausible - explanation for the gaff. If you are a devoted Trekkie looking for a response to your apostate friends when confronted over the scene, read on ...

QuinStar Exhibiting at American Physical Society March Meeting

QuinStar is Exhibiting at the American Physical Society March Meeting - RF CafeQuinStar Technology, a California-based microwave and millimeter-wave engineering company, will be exhibiting March 4-7 at the American Physical Society March Meeting in Boston. They will be showcasing its cryogenic product line, including a brand-new smaller housing. In addition, QuinStar is offering the unique opportunity to schedule one-on-one time with a design engineer while at the meeting. Appointments are available for March 5 and 6. QuinStar cryogenic components are used in quantum computing, particle physics research, and radio astronomy. They design and manufacture cryogenic isolators, circulators, and arrays onsite. Because the performance demands for cryogenic components are ever-changing to meet rapidly advancing technologies ...

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 ...

Monday 25

Antenna Reference Chart

Antenna Reference Chart, March 1953 Radio-Electronics - RF CafeSelecting the proper antenna for a particular application can mean the difference between success and failure when any combination of signal strength and/or signal interference is involved. Modern spread spectrum technologies has eased the job a bit, but there are still instances when high gain and/or directivity is necessary. You might be tempted to say that gain and directivity are essentially the same thing, and to some extent that is true. However, in the case of needing to minimize signal interference from surrounding sources, a directional antenna might be utilized not due to a need for increased desired signal strength but to reduce the power of undesired emitters. Such was often the requirement for television and FM radio reception. After years of needing to reorient the folded dipole antenna for my FM radio because ...

Saelig Intros Ruggedized Spectran XFR V5 PRO Realtime SpecAn

Saelig Introduces Ruggedized Spectran XFR V5 PRO Realtime Spectrum Analyzer - RF CafeSaelig Company, Inc., announces the Spectran XFR V5 PRO Real-Time Spectrum Analyzer - a portable, rugged RF detection device designed to capture even the briefest signal transmissions. Its rapid signal acquisition scans a 20 GHz bandwidth in less than 20 ms, making it the world's fastest counter-surveillance receiver. The instrument's internal GPS also indicates the precise location of the measured signals. Housed in a ruggedized, i7-based Windows 10 laptop with a sunlight-readable 15.6" display and magnesium alloy case, this analyzer is ready-to-go for covert outside field operations ...

Goddard Satellite Missions of the 1960s

NASA Goddard Satellites of the 1960 Decade - RF CafeAmerica's first successful orbiting of a satellite launch happened on February 1, 1958 with the launch of Explorer 1 atop a Juno 1 rocket. Our first attempted satellite launch was the Vanguard TV3, on December 6, 1957, but it unfortunately succumbed to a failed booster rocket (it rose only 4 feet off the launch pad). Russia had already launched its Sputnik 1 satellite on October 4, 1957, making it the very first manmade satellite to orbit the earth - to the forever chagrin of U.S. scientists. Fortunately, advances occurred rapidly for the U.S. space program after Explorer 1. In its first full decade of existence, the Goddard Space Flight Center, located in Greenbelt, Maryland, was responsible for launching more than 100 different spacecraft ...

everythingRF Live Coverage of MWC2019

everythingRF Mobile World Conference 2019 Live Coverage - RF CafeOnce again, the crew at everythingRF will be providing up-to-the-minute coverage of events at GSMA Mobile World Congress (MWC), being held this year in Barcelona, Spain, February 25 through 28. MWC2019 includes a world-class conference featuring visionary keynotes and thought-provoking panel discussions; an exhibition with more than 2,000 companies displaying the cutting-edge products and technologies that define the future of mobile; the world's best opportunity for mobile industry networking; and the annual Global Mobile Awards ceremony, which recognizes the most innovative mobile solutions and initiatives from around the world. It's a tough assignment, but somebody has to do it ;-)  ...

Physicists Take Big Step in Nanolaser Design

Physicists Take Big Step in Nanolaser Design - RF Cafe"Lasers are widely used in household appliances, medicine, industry, telecommunications and more. Several years ago, scientists introduced nanolasers. Their design is similar to that of the conventional semiconductor lasers based on heterostructures in common use for several decades. The difference is that the cavities of nanolasers are exceedingly small, on the order of the wavelength of the light they emit. Since they mostly generate visible and infrared light, the size is on the order of one millionth of a meter. Nanolasers have unique properties remarkably different from those of macroscopic lasers. However, it is almost impossible to determine at what current the output radiation of the nanolaser becomes coherent ..."

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 ...

Sunday 24

RF Cafe Engineering & Science Crossword Puzzle for February 24

RF Cafe Engineering & Science Crossword Puzzle February 24, 2019Beginning in 2000, I have created hundreds of custom technology-themed crossword puzzles for the brain-exercising benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. The jury is out on whether or not this type of mental challenge helps keep your gray matter from atrophying in old age, but it certainly helps maintain your vocabulary and cognitive skills at all ages. A database of thousands of words has been built up over the years and contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure village in the Andes mountains. You might, however, encounter the name of a movie start like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which, if you don't already know, might surprise you ...