Homepage Archive - April 2019 (page 3)

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 19

Mac's Radio Service Shop: Pride and Prejudice

Mac's Radio Service Shop: Pride and Prejudice, April 1955 Radio & Television News - RF CafeThere's not a much better way to finish up a hard week at the office than reading a new episode of John T. Frye's "Mac's Radio Service Shop." Mac McGregor and his trusty sidekick technician Barney tackle nearly every issue associated with an electronics sales and service establishment back in the heyday of radios and televisions. You might recognize the title of "Pride and Prejudice" as being borrowed from Jane Austin's classic, which, to summarize, deals with, well, pride and prejudice based on one's social status, and how it results in lost opportunities. To be honest, I have not read the book (Melanie's the designated book reader in our household) but I did see the movie version starring Keira Knightly. Anywho, you'll need to read the second half of the story to get to the actual pride and prejudice part ...

Noise and its Shaping in Ultra-Low-Noise Synthesizer Design

Noise and its Shaping in Ultra-Low-Noise Synthesizer Design - RF CafeThis is part 3 of a 5-part series of articles by Farron Dacus. You can access this and the previous two articles and "Noise and its Shaping in Ultra-Low-Noise Synthesizer Design" on the MW&RF website. "This third part in our low-noise synthesizer design series is the medium-length online version. In print are the abridged versions, while full-length versions are available at www.longwingtech.com. Part 1 (Dec. 2018) covered basic design for functionality and stability. Part 2 (Feb. 2019) covered the many noise sources in the synthesizer outside of the actual synthesizer IC. This third article looks into synthesizer IC noise, the closed-loop shaping of noises, and related issues such as optimum bandwidth. Here, a key metric for characterizing synthesizer IC noise is developed. This material also leads directly to analysis of optimum loop bandwidth ..."

Balloons Raise Shortwave Antenna

Balloons Raise Shortwave Antenna, April 1935 Short Wave Craft - RF CafeAntennas have been deployed in difficult environments using many ingenious methods over the years both by professionals and amateurs. The process typically involves first propelling a lightweight string or wire across and/or up to a supporting structure (a tower, tree, building, whatever) and then using that lead line to draw the antenna and its accompanying coaxial or twin lead cable into its final position. Sometimes simply tying a line to a rock and tossing it over a tree branch does the trick, but usually deployment requires a more powerful launch such as a a bow and arrow or even a model rocket. Many years ago R/C Modeler magazine reported on a large radio controlled airplane (Senior Telemaster) that towed a lead line across a wide gulch ...

Skyworks Waveguide Circulators for 5G Infrastructure

Skyworks Launches Suite of Custom Waveguide Circulators for 5G Infrastructure - RF CafeSkyworks Solutions, an innovator of high performance analog semiconductors connecting people, places and things, today unveiled its newest family of mini circulators for 5G infrastructure. Circulators, which play a critical role in protecting RF elements from excessive signal reflection, help eliminate performance risks and safeguard vital equipment. Given footprint constraints in 5G, solution size is also a key factor. Leveraging proprietary materials and processes, Skyworks' ultra-small circulators occupy up to 50 percent less board space than competitive products without compromising functionality - making them ideal for 5G massive MIMO and small cell applications. Skyworks' mini circulator family represents just one segment of the company's expansive 5G infrastructure ...

A Soluble Memristor

A Soluble Memristor - RF Cafe"This new memristor mimics the activity of neural networks, but can be thrown into water and dissolved if data is at risk of falling into the wrong hands. Neurons are remarkable. Simply by firing in certain patterns and at particular frequencies in concert with one another, they endow us with something incredibly valuable: memory. It's no wonder that scientists have long sought to mimic neural networks, which are both compact and efficient, with electronic devices. One way is with the development of memristors, devices that retain a 'memory' of the direction and amount of electrical charge ..."

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

Rohde & Schwarz RM & Microwave Test Equipment - 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 18

High-Fidelity Anagram (Crossword, Actually)

High-Fidelity Anagram, January 1960 Electronics World - RF CafeAccording to the Oxford English dictionary, the definition of an anagram is: a word or phrase made by using the letters of another word or phrase in a different order; e.g. "Neat" is an anagram of "a net." Therefore, the title of this puzzle appears to be misnamed. Sometimes an anagram crossword puzzle is created in which the clues are in the form of anagrams, but even that is not the case here. With any due apologies to author Comstock, I hereby re-title this a "High-Fidelity Crossword Puzzle." The "high-fidelity" part is entirely appropriate since it refers to the musical nature of the clues and words. As mentioned previously, the late 1950s through the early 1980s was a major era for interest in high fidelity radio receivers and playback gear. It represented the transition from powerful vacuum tube amplifiers to hybrid amplifiers, clear through to high power transistorized amplifiers. "Man caves" of the day were outfitted with the latest ...

Free e-Book: "73 Dipole and Long Wire Antennas"

73 Dipole and Long Wire Antennas - RF CafeMFJ Enterprises, probably the largest manufacturer of Ham radio equipment, is for a limited time offering a free downloadable copy of their e−book entitled, "73 Dipole and Long Wire Antennas." While on the MFJ website, you might want to take a look at the vast variety of products offered, including VSWR meters, high power attenuators and terminations, frequency counters, field strength meters, filters, amplifiers, EMI/RFI suppressors, antennas, antenna analyzers, coaxial switches, tuners, panel meters, and much more. While some stuff is specific to Ham bands, most can be used across very wide bandwidths ...

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!" ...

Electronics Poetry - "Pre-Radio"

Electronics Poetry - "Pre-Radio", June 1944 QST - RF CafeI learned something from this poem... or maybe I re-learned one of the many things taught to me that have been forgotten - the definition of a vinculum. I admit to having to look up the word in the dictionary after seeing it. How about you? Do you know what a vinculum is? A vinculum is a horizontal line placed over a number or numbers to indicating repeating groups (7/11=0.63), or for negation in Boolean equations (d=a-b+c), and it is also the dividing line between the numerator and the denominator; e.g. (½...

3D Print Metamaterials with Unique Microwave Properties

3D Print Metamaterials with Unique Microwave Properties - RF Cafe"Engineers at Tufts University have 3D printed metamaterials with unique microwave and optical properties that go beyond, what can be achieved by only using conventional optical or electronic materials. The fabrication methods developed by the researchers demonstrate the potential of 3D printing to expand the range of geometric designs and material composites that lead to devices with novel optical properties. In one case, the researchers drew inspiration from the compound eye of a moth to create a hemispherical device that can absorb electromagnetic signals ..."

Copper Mountain Technologies: Vector Network Analyzers

Copper Mountain TechnologiesCopper Mountain Technologies develops innovative and robust RF test and measurement solutions for engineers all over the world. Copper Mountain's extensive line of unique form factor Vector Network Analyzers include an RF measurement module and a software application which runs on any Windows PC, laptop or tablet, connecting to the measurement hardware via USB interface. The result is a lower cost, faster, more effective test process that fits into the modern workspace in lab, production, field and secure testing environments ...

Wednesday 17

Basic Laser Experiments

Basic Laser Experiments, June 1971 Radio-Electronics - RF CafeParenthetically mentioned in this introductory article on lasers is a "Mie" type particle. At first I thought maybe it was a typo, but in fact it refers to Mie scattering, which is the dispersion of electromagnetic waves by isolated spheres, stratified spheres, infinite cylinders, or other geometries where radial and angular dependence are independent. Two simple experiments are described for demonstrating light scattering and absorption similar to what occurs in the atmosphere. Whereas procuring the 2.5 mW laser source and to a lesser extent suitable light meter would have been difficult and expensive in 1971 when this was published in Radio-Electronics magazine, today's cheap equipment puts them within the budgets of almost anyone. Many of the <$10 cat toy lasers provide plenty of power ...

Altum RF Announces Greg Baker as Founder and CEO

Altum RF Announces Greg Baker as Founder and CEO - RF CafeAltum RF, a supplier of high-performance millimeter-wave to digital semiconductor solutions for next generation markets and applications, announces Greg Baker as its Chief Executive Officer. As founder and CEO, Mr. Baker brings more than 25 years' experience to Altum RF in the RF and microwave semiconductor industry, including component design, business development, marketing and sales. With his extensive experience, Mr. Baker provides a clear understanding of product development, operations and supply chain management, customer partnerships, sales channels and strategic marketing. Most recently with MACOM as Senior Vice President and General Manager, RF & Microwave BU, Mr. Baker also previously served as CEO ...

The Windsor Mystery Hum

The Windsor Mystery Hum - RF CafeIt is not often that a feature article in the ARRL's QST magazine is devoted to a topic totally unrelated to amateur radio. In fact, a cannot recall another instance in the 10+ years I have been a subscriber. The May issue's "The Windsor Mystery Hum" is not about an unidentifiable encroachment in the radio spectrum, but an audible and feelable vibration - in the sub-100 Hz range - believed to be emanating from a steel mill on Zug Island in Canada, across from Detroit. It began sometime around 2011, and no government will divulge its source. As you might expect, lots of conspiracy theories exist, but to date no confirmation of the origin. This is completely different from the 10 Hz "woodpecker" noise heard on HF radio receivers that has been tied to the Russian Duga over-the-horizon (OTH) radar.

Integrated Framework for Complex Radar System Design

Integrated Framework for Complex Radar System Design - RF CafeNI/AWR has an app note on the Aerospace & Defense Technology website enentitled, "An Integrated Framework for Complex Radar System Design." "Modern radar systems are complex and depend heavily on advanced signal processing algorithms to improve their detection performance. At the same time, the radio front-end must meet challenging specifications with a combination of available components, implementation technologies, regulatory constraints, requirements from the system, and signal processing. This application example shows how NI's Visual System Simulator™ (VSS) system simulation software enables radar system architects and RF component manufacturers to design, validate, and prototype a radar system .."

Platform for Open Wireless Data-Driven Experimental Research

Platform for Open Wireless Data-driven Experimental Research (POWDER) - RF Cafe"The National Science Foundation (NSF) funded program, Platforms for Advanced Wireless Research (PAWR), and a consortium of 29 industry partners, have now completed the first phase of deployment of an advanced wireless research testbed with end-to-end programmability of radio and edge compute resources in Salt Lake City, Utah. It offers researchers the ability to test groundbreaking communications technologies and to develop applications in a wide variety of virtual network environments. The announcement marks the successful completion of the first phase of a longer-term effort by the POWDER-RENEW team which consists of researchers from the University of Utah's Platform for Open Wireless Data-driven Experimental Research (POWDER) ...

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 ...

Tuesday 16

Philo T. Farnsworth Dies

Philo T. Farnsworth Dies, June 1971 Radio-Electronics - RF CafeNote that in the obituary of sorts for Philo Taylor Farnsworth, which appeared in the June 1971 edition of Radio-Electronics magazine, it specifically states that he was responsible for the development of the electronic television system, as opposed to the simple television system. That is because the earliest television schemes were as much - if not more - mechanical than electronic (see "Television Forges Ahead" in the March 1930 issue of Radio News). Philo invented the "image dissector" detector tube used in his video camera. Reconstructing the image with a cathode ray tube is a simple matter compared to first detecting the image. After his company was swallowed up by International Telephone and Telegraph (ITT) ...

Anatech Electronics March 2019 Newsletter

Anatech Electronics March 2019 Newsletter - RF CafeSam Benzacar, of RF and microwave filter company Anatech Electronics, has written as part of his March newsletter an article entitled, "AESA Is Coming to the Cellular Industry," with the AESA being an Active Electronically-Scanned Array. Sam keeps abreast of all the latest news in the wireless world, which is not unexpected given his company's long-time involvement in helping others make their products play well together in an increasingly crowded electromagnetic spectrum - both licensed and unlicensed. Other news includes the FCC's licensing of the 95 GHz, mm-wave band, Japan's first 8K (7680 × 4320-pixel) TV broadcasts, and Bluetooth devices being powered from ambient energy - assuming it's inside in front of a transmitting radar antenna ;-) ...

Thanks to Transient Specialists for Continued Support!

Transient Specialists - RF CafeTransient Specialists specializes in EMC test equipment rentals and carries a complete line of ESD guns, surge immunity test equipment, and EFT generators. Rentals available for military (Mil-Std 461), automotive (ISO 7637), and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited calibrations and technical support on EMC testing equipment offered. Equipment consists of top EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and EMC Partner ...

Mac's Radio Service Shop - Barney Talks A.C.-D.C.

Mac's Radio Service Shop: Barney Talks A.C.-D.C., September 1949 Radio & Television News - RF CafeHave you ever heard of a 'globar' resistor? They have been around since the early days of radio and were used, among other things, to protect vacuum tube heater elements from burning up due to high inrush current when first turned on. Globars have a negative temperature coefficient (NTC) of resistance so that, opposite of standard carbon and metal film type resistors, they exhibit a higher resistance when cold than when hot. Mac and Barney discuss their use in this episode of "Mac's Radio Service Shop." You might be more familiar with the name 'thermistor' for such devices, but globars are unique elements in that their construction from non-inductive ceramic material makes them useful at high power levels and high frequencies ...

Planar Monolithic Industries' (PMI) April 2019 Product Announcement

Planar Monolithic Industries (PMI) April 2019 Product Announcement - RF CafePlanar Monolithic Industries (PMI) recently introduced seven - count 'em, 7 - new products in their extensive line of RF and microwave components. Included are a successive detection log video amplifier (SDLVA) for 0.1 to 2.0 GHz; a 18 GHz, 12-BIT, vector phase shifter; a 5-channel switched filter bank for 100 MHz - 18.0 GHz; a SP16T, absorptive pin diode switch for 0.1 to 20.0 GHz; a 2-channel switch filter bank; an SDLVA that operates at 200 - 2500 MHz; and a 7-way power divider for range 328 - 335.5 MHz. Contact PMI today for more information ...

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 ...

Scalable Agile Beam Radar (SABR) for Fighter & Bomber Platforms

Scalable Agile Beam Radar (SABR) for Fighter & Bomber Platforms - RF Cafe"Northrop Grumman has successfully integrated the advanced AN/APG-83 SABR system onto multiple configurations of F−16 aircraft and is now taking the next step in expanding to additional platforms, including the U.S. Air Force (USAF) B−52H Stratofortress and B−1B Lancer bombers as well as the U.S. Marine Corps F/A−18C/D Hornet strike fighter. Northrop Grumman's SABR system design leverages proven, fifth-generation Active Electronically Scanned Array radar capabilities of the AN/APG−77 on the F−22 Raptor and the AN/APG-81 on the F−35 Lightening II. SABR provides a reliable, cost-effective, off-the-shelf, low-risk radar upgrade solution for multiple platforms ..."

Monday 15

Chemicals for Electronics

Chemicals for Electronics, May 1971 Popular Electronics - RF CafeFollowing the previous month's introduction to "Chemicals for Electronics," which covered degreasers, cleaners, and polishing agents, author Lon Cantor in the May issue of Popular Electronics wraps up with coolers, lubricants, and special agents (no, not spies) such as protective and insulating coatings. He devotes a lot of space to freeze spray for use in troubleshooting problems caused by overheating circuit components. In the days before comprehensive computer aided design environments that can identify heat concentrations with detailed temperature maps and design rules checks (DRC), predicting potential overheating sources in both normal operation and during impending failure was much more difficult. Running a large series of worst case scenarios ...

Overcome mmWave Automotive Radar Testing Challenges

Overcome mmWave Automotive Radar Testing Challenges - RF CafeDriverless and self-driving cars are on the road today in various stages of experimentation. Recent headlines about the Boeing 737-Max automation catastrophe has me a bit dubious about the sanity of handing the controls over to robots, but I suppose it is inevitable. In that case the AI evidently wrested control from the backup human pilots. Scary. Radar, lidar, and sonar are all technologies key to automotive automation. Mark Elo has a good article on the MW&RF website entitled, "Overcome mmWave Automotive Radar Testing Challenges." He begins: "With automotive radar moving to higher frequencies, the need exists for the right test solutions such as high-bandwidth oscilloscopes and versatile arbitrary waveform generators. Recent regulation changes have allowed the automotive radar market to shift from the 24 GHz band to the 77 GHz band, introducing a range of new design and test challenges ..."

Digital Pre-Distortion, Envelope, Outphasing and Doherty Transmitter

Digital Pre-Distortion, Envelope, Outphasing and Doherty Transmitter - RF CafeRohde & Schwarz has published four new application notes on the subjects of Digital Pre-Distortion, Envelope, Outphasing and Doherty Transmitter. "RF design is becoming increasingly difficult, as frequency and bandwidths increase. Be it power amplifier, or RF Frontends, power consumption and energy efficiency is a key challenge that increases at higher frequencies. In this resource library, we have collected a few pieces that address power consumption in power amplifier (PA), power efficiency for RF Frontends (RFFE) and wideband signal generation and analysis in general. Learn about test solutions for Envelope Tracking and Digital Pre-Distortion, or Envelope, Outphasing & Doherty Transmitter tests ..."

Mathematics in Radio, Calculus and its Application in Radio

Mathematics in Radio, Calculus and its Application in Radio, July 1932 Radio News - RF CafeI challenge you to find a calculus lesson in a modern-day electronics magazine. In 1932, not all that long after Isaac Newton developed differential calculus (that's a joke), Radio News magazine ran a series of "Mathematics in Radio" articles that included, among other topics, a few lessons in calculus. Anyone who has taken college-level science or engineering courses knows how indispensible calculus is in working out many circuit, physics, and chemistry problems. My appreciation for calculus came when I realized that it actually allowed me to derive the kinds of standard equations that are commonly seen in lower level applications. For instance, if you needed to know the volume of a sphere, you could look up the familiar Volume = 4/3 π r3 formula, or you could write the equation ...

Spin Lasers Facilitate Rapid Data Transfer

Spin Lasers Facilitate Rapid Data Transfer - RF Cafe"Engineers have developed a novel concept for rapid data transfer via optical fiber cables. In current systems, a laser transmits light signals through the cables and information is coded in the modulation of light intensity. The new system, a semiconductor spin laser, is based on a modulation of light polarization instead. The study demonstrates that spin lasers have the capacity of working at least five times as fast as the best traditional systems, while consuming only a fraction of energy. Engineers at Ruhr-Universität Bochum have developed a novel concept for rapid data transfer via optical fiber cables. In current systems, a laser transmits light signals through the cables and information is coded in the modulation of light intensity ..."

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 ..."

Sunday 14

Engineering & Science Crossword Puzzle for April 14

RF Cafe Engineering & Science Crossword Puzzle April 14, 2019Since 2000, I have been creating 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 star like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which, if you don't already know, might surprise you ...