Homepage Archive - January 2019 (page 5)

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

2024:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

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)


See Page 1 | 2 | 3 | 4 | 5 of the January 2019 homepage archives.
col-width

Thursday 31

Microwave Klystron Oscillators

Microwave Klystron Oscillators, May 1952 Radio & Television News - RF CafeBy now, engineers and scientists have managed to replace most vacuum tubes with solid state devices - at least for consumer products. The one place tubes remain are in microwave oven. Those klystron tubes operate in the 2.4 GHz band and typically output ranging from about 500 W to 2 kW. No doubt materials and methods have changed since the 1950s, but fundamentally klystrons of today are the same as klystrons then. Between this article and Part 1 that appeared in the April 1952 issue of Radio & Television News magazine, authors Joseph Racker and Lawrence Perenic provide a very nice introduction on the topic. According to the Wikipedia entry, the name "klystron" comes from the Greek verb κλύζω (klyzo) referring to the action of waves breaking against a shore, and the suffix -τρον ("tron") meaning ...

Raspberry Pi PCB Antenna 4D Radiation Pattern Measurement

Raspberry Pi PCB Antenna 4D Radiation Pattern Measurement - RF CafeGlenn Robb is a busy guy. I addition to running his Antenna Test Labs facility, he has created numerous educational projects. Late last year he made news with 3D-printed microwave feedhorns, and this latest endeavor is this 4D plot of the popular Raspberry Pi printed WiFi band PCB antenna. Says Glenn, "This antenna example is a common and popular option for most IoT devices operating in the 2.45 GHz WiFi ISM band. It is a PCB antenna designed by Proant AB and replaces the dielectric SMT chip antenna previously used the Pi's. The design is a planar resonant cavity using two sets of SMT capacitors to setup resonances in the 2450 and 5800 MHz WiFi ISM bands. While small antennas are convenient and often inexpensive, they compromise performance for their size trade-off. This example antenna evaluation will show the actual radiation efficiency ..."

5G mmWave: A Challenge for Device Testing and How to Solve It

5G mmWave: A Challenge for Device Testing and How to Solve It - RF CafeRohde & Schwarz and Microwave Journal will present a free webinar on February 13, titled, "5G mmWave: A Challenge for Device Testing and How to Solve It." Günter Pfeifer discusses how 5G NR in the sub 6 GHz frequency range (FR1) can be seen as a natural evolution of LTE to achieve higher bandwidth and more flexibility on the physical layer in order to realize all the new and additional use cases defined for a next generation mobile network. "The real technical challenge, however, comes with 5G mmWave (FR2), which opens up a new level of complexity in device development. mmWave frequencies imply measurement challenges that call for new testing approaches. In this webinar, we take a closer look at the major challenges mmWave brings and discuss innovative test ..."

Monte Carlo Gone Wrong

Monte Carlo Gone Wrong - RF CafeI remember my first experience with Monte Carlo analysis was in my first job at General Electric in Utica, NY, immediately after graduating from UVM with a BSEE degree. It involved using the early version of EEsof Touchstone that used Spice type netlist circuit description entry. The topic was a bank of switchable bandpass filters for an airborne EW receive unit. I also used OmniSys for optimizing the RF path. It was mesmerizing watching the multicolored lines get drawn on the screen as the software converged on a solution - or didn't. Charles Hymowitz has an interesting article on the EDN website titled, "Monte Carlo Gone Wrong" ...

Private Satellites Open Uncharted Territory in Data Collection

Private Satellites Open Uncharted Territory in Data Collection - RF CafeWatching this video of miniature satellite launches from a spaceborne pod is both cool and spooky. It reminds me of an alien invasion vessel deployment from a sci-fi movie. Per the report: "A company has launched hundreds of small satellites capturing over a million photos of Earth each day for commercial use, offering unimagined possibilities and consequences. Planet Labs, the satellite company, has launched hundreds of small satellites for commercial use, such as monitoring the health of crops. They get over a million photos from them each day. 'I'm always astonished that almost every picture we get down, we compare it to the picture from yesterday and something has changed,' says one of the company's founders, Will Marshall. Planet Lab has 200 customers, none more important than the U.S. Government ..."

PCB Directory: Printed Circuit Board Fabrication & Assembly

PCB  Directory - RF Cafe

PCB Directory is the largest directory of Printed Circuit Board (PCB) Manufacturers, Assembly houses, and Design Services on the Internet. We have listed the leading printed circuit board manufacturers around the world and made them searchable by their capabilities - Number of laminates used, Board thicknesses supported, Number of layers supported, Types of substrates (e.g., material, flexible, rigid), Geographical location, and more ...

Wednesday 30

U.S. Television Stations and Network Links Map

U.S. Television Stations and Network Links Map, May 1952 Radio & Television News - RF CafeIf my counting is correct, by 1952 only 33 of America's 48 states (Hawaii and Alaska weren't admitted until 1959), and Washington, D.C., had television broadcasting stations. That most of the early television experimentation occurred on the east coast is apparent by looking at the number of stations there compared to the west coast. You might think California would have the largest amount of TV stations, but it only had 11 located in 3 cities. New York, on the other hand, had 13 in 7 cities. Ohio had 12 stations in 5 cities, and Pennsylvania had 7 stations in 5 cities, one of which was my town of Erie. Vermont, New Hampshire, Mississippi, Wyoming, both Dakota, and Oregon were among those with no television stations by 1952. That seems unbelievable since that was only 67 years ago, but evidently was so. The network "lines" included microwave repeaters to reach from coast to coast. On September 4, 1951, AT&T opened the network by televising a presidential address ...

New Product Releases by Planar Monolithic Industries (PMI)

Planar Monolithic Industries (PMI) April 2018 Product Announcement - RF CafePlanar Monolithic Industries (PMI) recently introduced three new products in their extensive line of RF and microwave components. Included are a 2.0 to 18.0 GHz high speed single pole six throw reflective switch capable of switching within 15 ns, a 2.0 to 18.0 GHz 8-Bbit vector phase shifter, and a 2-channel switch filter bank with a low-pass 8.62 to 8.70 GHz filter and a 8.0 to 26.5 GHz bandpass filter. Contact PMI today for more information ...

de Forest's Syncro-Graphic Training Ad

de Forest's Syncro-Graphic Training Ad, September 1945, Radio-Craft - RF CafeI have never seen study-at-home audio-visual (AV) physics courses offered by Albert Einstein or AV courses on chemistry promoted by Ernest Rutherford, but I can now say I have seen study-at-home AV courses offered by electronics pioneer Lee de Forest. This full-page advertisement for the de Forest's Training, Inc., company of Chicago, Illinois, appeared in a 1945 edition of Radio-Craft magazine. The vaunted (at least by the company) "Syncro-Graphic" training was an early attempt at the paperless classroom. The student watched films reels of instruction rather than "frequent flipping of pages to refer back or ahead to illustrations mentioned in text." It would be another 50 years before useful computer-based-training (CBT) courses became available for home use, but you have to give the "Father of Radio" credit for being ahead of his time in instruction techniques ...

Automotive Radar and Congested Spectrum

Automotive Radar and Congested Spectrum: Potential Urban Electronic Battlefield - RF CafeAlong with the rapidly advancing technology of self-driving vehicles and sensor-assisted driving has come crowded spectrum in the mm-wave bands (see "Why Are Automotive Radar Systems Moving from 24 GHz to 77 GHz?"). Sefa Tanis, of Analog Devices, has published an article titled, "Automotive Radar and Congested Spectrum: Potential Urban Electronic Battlefield," in Microwave Journal. "As automotive radars become widespread, the heavily occupied RF spectrum in an urban environment will resemble an electronic battlefield. Radar will face a combination of unintentional-even intentional-jamming, and designers must implement counter-jamming techniques like ones used in electronic warfare (EW) ..."

Promote Your Company on RF Cafe for as Little as $35/Month

Sponsor RF Cafe for as Little as $35 per Month - RF CafeRF Cafe typically receives 8,000-15,000 website visits each weekday and about half that on weekends. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 7,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. I also re-broadcast homepage items on LinkedIn, Facebook, and Twitter. If you need your company news to be seen, RF Cafe is the place to be. Banner advertising begins at $150/month ...

New Material to Overcome Limits of Silicon and Even GaN

New Material to Overcome Limits of Silicon and Even GaN - RF Cafe"In power electronics, the silicon technology that predominates today will no longer be able to meet the growing demands in the foreseeable future. Scientists from the University, the Fraunhofer-Gesellschaft and power centers have joined forces to research a novel material structure that will meet the requirements of industry for future components much better. Scientists therefore are investigating a rather exotic material most electronics engineers probably never have heard of: ScAIN. Two main factors are responsible for the growth of the electronics market: the automation and digitization of the industry as well as the increasing awareness of ecological responsibility and sustainable processes. Energy consumption ..."

Empower RF Systems: RF & Microwave Power Amplifiers

Empower RF SystemsEmpower RF Systems is a global leader in power amplifier solutions. Empower RF Systems is an established and technologically superior supplier of high power solid state RF & microwave amplifiers. Our offerings include modules, intelligent rack-mount amplifiers, and multi-function RF Power Amplifier solutions to 6 GHz in broadband and band specific designs. Output power combinations range from tens of watts to multi-kilowatts. Unprecedented size, weight and power reduction of our amplifiers is superior to anything in the market at similar frequencies and power levels ...

Tuesday 29

The Amazing Transistor

The Amazing Transistor, April 1952 Radio & Television News - RF CafeLess than half a decade had passed when Radio & Television News editor Oliver Reed wrote this piece extolling the virtues of the transistor and how "it may well revolutionize the entire electronics industry." If you have followed a lot of my postings from the vintage electronics magazines here on RF Cafe, you are well aware that there was a lot of resistance to and doubt about the future of semiconductors. Naysayers had the same kind of reaction to the advent of the horseless carriage (automobile) and locomotive, relativity and quantum mechanics, and even curative medicines. Point contact transistors were still largely in use, but were costly compared to the relative simplicity and low cost of junction transistors once the manufacturing details were worked out - which, as we now know, happened very rapidly. By 1965 the process was so refined that Gordon Moore ...

The Beginner's Guide to Digital Electronics

The Beginner's Guide to Digital Electronics - RF CafeEverybody has to start somewhere when learning about digital logic, and Roger Secura has provided just what's needed with "The Beginner's Guide to Digital Electronics," on the Nuts & Volts website. "This article was written specifically for the newcomer to the field of digital electronics. If you've always wanted to know how the digital world works, then keep reading. You don't need to know calculus, algebra, or any complex formulas to finish this article. The only requirements are an interest in digital electronics and a desire to learn. Since you're reading this paragraph, obviously you're at least a bit curious about the digital world. Fortunately, curiosity is half the battle to enlightenment ..."

Keysight Intros ADS PathWave Product Development Workflow Software

Keysight Technologies Accelerates Product Development Workflows with New PathWave Advanced Design System Solutions - RF CafeKeysight Technologies, a leading technology company that helps enterprises, service providers, and governments accelerate innovation to connect and secure the world, announced PathWave Memory Designer, a new double data rate (DDR) memory simulation capability that is part of PathWave Advanced Design System (ADS) 2019. The new capability makes it easy for developers to compare simulated data with actual measured results, reducing the time required to complete product development workflows. DDR memory designs grow more complex with each new generation, and simulation and test configuration also grow in complexity, resulting in longer simulation and test setup times. The added complexity makes it harder to correlate simulation and test data, resulting in less confidence in designs, longer troubleshooting cycles ..."

What's That Signal's Bandwidth?

What's That Signal's Bandwidth? - RF CafeBob Witte has a brief primer titled, "What's That Signal's Bandwidth?" on the EDN website. "The term bandwidth is used and abused in many situations. I recall one meeting where the word was used to refer to: the frequency content of a particular signal, the frequency response of a specific circuit, the speed of our local area network and the human capacity of the organization. 'We just don't have the bandwidth to handle the workload right now.' I don't think anyone else noticed, but I found it humorous. Signal bandwidth Engineers will ask the question 'how much bandwidth do I need for that signal?' Typically, the question relates to making sure that the signal can propagate through a component or system and come out the other end without any degradation ..."

New GPS Positioning Technology in Tesla Patent Application

New GPS Positioning Technology in Tesla Patent Application - RF Cafe"Looking to enhance accuracy, the concept uses Earth-based cars sharing data and generating corrections. In a patent application filed in 2017 and made public last month, Tesla describes a technology that it believes will result in more accurate GPS positioning. The proposed invention would increase positioning accuracy via determining and applying offsets - corrections - in various ways and sharing this information between vehicles. Tesla describes a system of matching camera data with vision maps to detect the exact location of a vehicle. In essence, the system involves using camera sensors on Tesla EVs to fine-tune the GPS data ..."

Many Thanks to Anatech Electronics for Long-Time Support!

Anatech Electronics logo - RF CafeAnatech Electronics (AEI) manufactures and supplies RF and microwave filters for military and commercial communication systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard RF filter and cable assembly products are published in our website database for ease of procurement. Custom RF filters designs are used when a standard cannot be found, or the requirements dictate a custom approach. Sam Benzacar's monthly newsletters address contemporary wireless subjects. Please visit Anatech today to see how they can help your project succeed ...

Monday 28

Medical Electronic Equipment and Hospital Safety

Medical Electronic Equipment and Hospital Safety, January 1972 Popular Electronics - RF CafeThe history of electrical current is replete with tragic incidences of maiming and death caused by ignorance and/or inattention to known danger. Having been involved in both the electrical wiring and the electronics fields since the 1970s, I am quite aware of the legion of hazards present when current flows. My tool box contains screwdrivers and lineman's pliers with notches of melted metal from inadvertent contact between differences of potential in circuit breaker panels and electrical wall boxes. Once you experience the thrill of a sudden blinding flash, unique buzzing sound, and smell of burning hot steel, you'll never forget it. Those incidences could have been avoided with more careful work practices. A lot of people have been electrocuted, though, through no fault of their own, if ignorance (as opposed to stupidity) is a valid excuse. Early radios, televisions, and other household appliances did not have a safety ground ...

Engineering Career and Job Hunting Advice

/2019/Engineering-Career-Advice-Articles-January-2019.htm" target="_top" > Engineering Career and Job Hunting Advice for January 2019 - RF CafeIt has been a few months since I posted a list of useful articles on engineering and other technology job search and career enhancement topics from around the Web. Very noticeable when reviewing the subjects of most of these websites is a very high concentration on social issues rather than on job performance and competency /2019/Engineering-Career-Advice-Articles-January-2019.htm" target="_top" >...

Why Companies Need Engineers with a Creative Bent

How to Answer Common Interview Questions

Things to Double-Check Before Submitting a Cover Letter

Report: 2019's Best Jobs

Why Women Need to Network

The Many Ways to Get a Job Before Graduation  </2019/Engineering-Career-Advice-Articles-January-2019.htm" target="_top" >more>

Helga and Zohar Space Travel Radiation Protection Suits

Helga and Zohar Space Travel Radiation Protection Suits - RF CafeQ: How do you make sure as many men as possible read your news release about a radiation protection suit for long-term space flight? A: Use lead photo of two women with terraced vests, along with an opening line of, "Meet Helga and Zohar, the dummies destined for a pioneering lunar flyby to help protect space travelers from cosmic rays and energetic solar storms." The con is that you are never explicitly told those two women are not "twin dummies" Helga and Zohar. The Japanese have created some incredibly lifelike dummies, but none this convincing. A quick Google search turned up info explaining why the real Helga and Zohar, if used in that lead photo, would not have garnered nearly as much attention. A more important question might be who... or what... is the biggest dummy? Helga, Zohar, the women in the photo, or me (for digging into the details of the story)? ...

Planning Integrated Signal Communications

Planning Integrated Signal Communications, December 1950 Radio & Television News - RF CafeThe U.S. Army's Signal Corps was set up to "exercise supervision over signal communications literally from the Pentagon to the foxhole." Created in 1860 at the suggestion of a military doctor, the Signal Corps originally used a system of flag waving for messaging dubbed "wigwag" and graduated to overseeing the nationwide telegraph network six years later. By 1870, members were tasked with establishing and operating a weather forecasting service, so in 1907 when they created an aeronautical division it was just in time for facilitating the nation's rapidly growing cadre of aircraft pioneers (recall the Wright brothers had flown four years earlier at Kitty Hawk) by providing en route weather information. Having already mastered the state of the art that was radio and telephone ...

Hail the Perovskite Transistors

Hail the Perovskite Transistors - RF Cafe"Researchers have created a field-effect transistor using a single-crystal, 'paint-on' perovskite. Transistors, and the conductive traces that connect them, are routinely created by the billions on the surface of silicon wafers, which are later cut into the individual 'chips' that power our computers, phones, watches, and countless other electronic gadgets. But few people think much about how those silicon wafers are made in the first place. It's quite tricky. Very pure sand (silicon dioxide) has to be melted, at which point a seed crystal of elemental silicon is brought in contact with the melt, which slowly deposits silicon atoms on the seed, ones that extend the seed's crystalline lattice ..."

Res-Net Microwave: Precision RF & Microwave Components

Res-Net Microwave componentsRes-Net Microwave has a complete line of precision RF & microwave components including attenuators, terminations, resistors, and diode detectors for commercial, military, and space applications. Products range from the small flange type to large 2,000 watt connectorized power attenuators and/or terminations at frequencies up to 26.5 GHz. In-house photo etch and laser trim capability. Please check out Res-Net Microwave's website to see how they can help with your current project ...

Sunday 27

RF Cafe Engineering & Science Crossword Puzzle

RF Cafe Engineering & Science Crossword Puzzle January 27, 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! ...