Homepage Archive - September 2020 (page 3)

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Monday 21

RCA Electron Tubes

RCA Electron Tubes, November 1951 Radio & Television News - RF CafeI like the tag line RCA chose for this 1951 advertisement pitching their vacuum tubes: "Electron tube with a military mind." However, what really caught my attention was the illustration that borrows the "ship in a bottle" theme. A lot of younger people might have no idea what is being alluded to given easy access to cheaply manufactured faux examples. Modern manufacturing techniques makes it relatively simple to form a bottle (especially a plastic one) around a pre-built ship model. The original technique required preparing much of the model as possible ahead of time, and then inserting the individual pieces through the narrow bottle neck and performing assembly using long nosed pliers and/or tweezers. A lot of preparation, patience, and skill is required to make a fine looking model. Maybe the advertisement creators stumbled upon this...

Carl & Jerry: Tussle with a Tachometer

Carl & Jerry: Tussle with a Tachometer, July 1960 Popular Electronics - RF CafeThis is a great example of how Popular Electronics and John T. Frye used the "Carl & Jerry" series to teach some basic electronics design principles through story telling. The same is true with his long-running "Mac's Service Shop" series of techno-dramas. In this adventure, the the two teenagers decide to build a tachometer from schematics they found in a magazine. They debate amongst themselves how the circuits works, the best way to assemble the circuit, component selection, vibration-tolerant mounting, and how to properly calibrate the tach to accurately display engine revolutions per minute (RPM). Being set in 1960, this is one of the first appearances of transistors in circuits rather than vacuum tubes. Transistors were still very mysterious - and even detested - by many electronics hobbyists and professionals, so pieces like this...

Aerogels Protect Against Electromagnetic Interference

Aerogels Protect Against Electromagnetic Interference - RF Cafe"Researchers at Empa, the Swiss Federal Laboratories for Materials Science and Technology, have succeeded in applying aerogels to microelectronics: aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range - and they are unrivalled in terms of weight. Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic components or the transmission of signals. High-frequency electromagnetic fields can only be shielded with conductive shells that are closed on all sides. Often thin metal sheets or metallized foils are used for this purpose. However, for many applications such a shield is too heavy or too poorly adaptable to the given geometry..."

Heathkit IM-17 Utility Solid-State Voltmeter

Heathkit IM-17 Utility Solid-State Voltmeter - RF Cafe Cool ProductSometime around late 1977, a year or so prior to reporting to Lackland Air Force Base for Basic Military Training with plans to pursue a career in electronics, I began boning up on my admittedly lacking electronics skills. Having spent the past few years as an electrician, including a couple years in vocational school, I was familiar enough with the big stuff that could easily kill me, but I didn't know much about about electronics with its small components and low voltages. To assist me with my goal, I purchased a couple Heathkit kits and carefully studied all the information provided, then proceeded to assemble and test everything. My first project was this IM−17 Utility Solid-State Voltmeter. It was simple enough for even me to be successful. Although it was called a voltmeter (AC and DC capability), it also measured resistance, so technically it was a volt-ohmmeter. I'm not sure why the designers didn't add a current measuring function...

PCBONLINE Introduces Rigid-Flex PCBs

PCBONLINE Introduces Rigid-Flex PCBs - RF CafePCBONLINE's Rigid-Flex PCBs are boards with 3D design using a combination of flexible and rigid board technologies, and have characteristics of both soft and hard boards. Therefore, they can be used in electrical devices with special requirements, such as connecting a flexible area and a rigid area. Rigid-flex PCBS save the internal space of electrics, reduce the size, and improve electrical and mechanical performance of electronic devices. In PCBONLINE, rigid-flex PCB manufacturing and assembly are operated under strict quality control. The final board thickness ranges from 0.05 mm to 0.6 mm.

Many Thanks to Exodus Advanced Communications for Their Support

Exodus Advanced Communications - RF CafeExodus Advanced Communications is a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide. Power amplifiers ranging from 10 kHz to 51 GHz with various output power levels and noise figure ranges, we fully support custom designs and manufacturing requirements for both small and large volume levels. decades of combined experience in the RF field for numerous applications including military jamming, communications, radar, EMI/EMC and various commercial projects with all designing and manufacturing of our HPA, MPA, and LNA products in-house.

Sunday 20

Science & Engineering Themed Crossword for September 20th

Science & Engineering Themed Crossword Puzzle for September 20th, 2020 - RF CafeSeptember 20th's custom Science & Engineering themed crossword puzzle contains only only words from my custom-created lexicon related to engineering, science, mathematics, chemistry, physics, astronomy, etc. (1,000s of them). 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, find someone or something in the otherwise excluded list directly related to this puzzle's technology theme, such as Hedy Lamarr or the Bikini Atoll, respectively. The technically inclined cruciverbalists amongst us will appreciate the effort.

Friday 18

On Signal Strength Evaluation

On Signal Strength Evaluation, October 1976 QST - RF CafeIt is always interesting to look back many years ago and see what people thought were the big issues of the day. According to this 1975 QST article, some amateur radio operators thought the decades old S-scale system for determining signal strength using a combination of objective and subjective measures was in need of modernization. Nine separate levels of signal strength was, in this author's estimation, too many to provide a meaningful report to the sender regarding how well his message was being received. Five was plenty. He had a good point since, as pointed out, can an operator really say whether a signal quality rated a score of S5 versus S6? History has been the judge of the matter, and now 44 years later...

Army Advances Materials for Low-Profile Antenna

Army Advances Materials for Low-Profile Antenna - RF Cafe"Army scientists developed a first-of-its kind antenna that could change how ground vehicles and airborne systems communicate, transmit and receive radio frequency communications. The Army matured a manufacturing process using a special class of engineered materials known as metaferrites to make an ultra-thin wideband antenna. The antenna conforms to curved surfaces, making it ideal to integrate in unmanned aircraft systems, rotary wing aircraft and ground vehicles. 'Recognizing the potential of metaferrites in antenna design and making a decision to invest in this technology were key to where we are today,' said Dr. Philip Perconti, deputy assistant Secretary of the Army for Research and Technology..."

EE Times™ Opening Screen Annoyance

EE Times™ Opening Screen Annoyance - RF CafeAm I the only one who finds the opening screen to the EE Times website very annoying? I have been sending visitors there for news and articles for many years, and for a long time they have been putting up this stupid opening screen in order to get to the content. No other tech website I can think of does this kind of stupidity. I've been considering removing them from news bookmarks, and will probably do so soon.

Op Amps for Linear Designs: Back to the Basics

Op Amps for Linear Designs: Back to the Basics - RF CafeProfessor Frenzel has a new post on the Electronic Design website entitled, "Op Amps for Linear Designs: Back to the Basics." Lou F. has provided the electronics community with many articles (and book) covering a wide range of topics fundamental to the craft. He begins, "Op amps are the basic building blocks for much of linear circuit design. You probably learned about them in college and even designed some products containing an op amp. As an electronic engineer, you will at some point in your career probably need to design a linear circuit. If you're not an advanced linear or analog circuit designer, perhaps the best way to fulfill your linear design needs is to use an op amp..."

Please Visit Triad RF Systems to Thank Them for Their Support

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.

Electronics-Themed Comics from the 1960s

Electronics-Themed Comics from May 1961, February 1967, & May 1967 Electronics World - RF CafeThank God It's Friday (TGIF) again. What better way is there to wrap up a week than to get a good laugh at these electronics-themed comics from a few of my vintage Electronics World magazines from the 1960s? If you still need more to help recover from the past five days and prepare you for the weekend, a huge list of other webpages with similar comics is at the bottom of this page. They would make good additions to in-house presentations.

Fork Test Labs Intros Inexpensive Analog and Digital I/O Fixture

Fork Test Labs Intros Inexpensive Analog and Digital I/O FixtureFork Test Labs introduces the Fork programmable I/O interface board for test-engineers to automate fixtures - for only $95! Everyone knows or has seen big test stands, but few can use them because they are very expensive and not many engineers can put in hours or days to make it work as needed. So, we decided to create a platform for testing to help engineers in their everyday hard work. Just take Fork, PyTest and program the tests in Python. Features include 8 digital I/O, 8 analog inputs, 2 analog outputs, Ethernet and Wi-Fi connectivity, and 3 UART, SPI or I2C for connection with external devices...

Many Thanks to LadyBug Technologies for Their Continued Support!

LadyBug Technologies RF Power Sensors - RF CafeLadyBug Technologies was founded in 2004 by two microwave engineers with a passion for quality microwave test instrumentation. Our employees offer many years experience in the design and manufacture of the worlds best vector network analyzers, spectrum analyzers, power meters and associated components. The management team has additional experience in optical power testing, military radar and a variety of programming environments including LabVIEW, VEE and other languages often used in programmatic systems. Extensive experience in a broad spectrum of demanding measurement applications. You can be assured that our Power Sensors are designed, built, tested and calibrated without compromise.

Thursday 17

Shielding in Hi-Fi Equipment

Shielding in Hi-Fi Equipment, December 1955 Radio & Television News - RF CafeRecently, I posted from this same 1955 issue of Radio & Television News magazine the article "Mac's Service Shop: Magnetic Shielding." Maybe it was a coincidence that it was printed in the same issue as this article entitled, "Shielding in Hi-Fi Equipment," but probably not. Discussed here are all three fundamental kinds of fields from which equipment and/or components might require shielding to prevent cross-coupling of signals: Magnetostatic, electrostatic, and electromagnetic. An electromagnetic field is present whenever either a magnetic or electric field is varying since one begets the other. Different types of shielding materials are required for blocking a magnetic field versus an electric field, where material permeability and conductivity, respectively, determines effectiveness. In the era when this was written, most electronic equipment consisted of leaded (not Pb'd) components interconnected inside a metal chassis via point-to-point wiring with all combinations...

Tunable Microwave Reflector Is Next-Generation Antenna

Tunable Microwave Reflector Could Be the Next-Generation Antenna - RF Cafe"Engineers at Los Alamos National Laboratory are reinventing the mirror, at least for microwaves. Their invention could replace the familiar satellite dishes and microwave horns seen on rooftops and cell towers with flat panels that are compact, versatile and better adapted for modern communications. 'Our new reflectors offer lightweight, low-profile alternatives to conventional antennas. This is a potential boon for satellites, where minimizing weight and size is crucial,' says Abul Azad, of the MPA-CINT group at Los Alamos National Laboratory. 'The panels could be easily incorporated onto surfaces of buildings or terrestrial vehicles as well.' Most reflectors are reciprocal. So, if you can see someone reflected in a mirror, they can see you too. The new reflector design breaks reciprocity, effectively turning it into a one-way mirror..."

BNC Webinar: Choosing the Perfect RF Signal Generator

BNC Webinar: Choosing the Perfect Microwave Signal Generator (Free Admission) - RF CafeBerkeley Nucleonics Corporation (BNC - like the connector) will present a free webinar on Wednesday, October 7th, 2020, entitled, "Choosing the Perfect RF/Microwave Signal Generator." Catch up with Berkeley Nucleonics and several special guests in the upcoming webinar to explore the inner workings of microwave signal generators. This in-depth webinar will provide a deeper look at basic specifications such as modulation, channels, power, accuracy, and speed. Senior Product Manager Junior Choe will do the presentation running from 10:00-11:00 am Pacific Time to assist RF/microwave experts in determining the precise signal generator for their applications. Engineers use these signal generators to test systems for a wide range of applications throughout the product development cycle. By attending this webinar, you receive free access to BNC Academy's RF Bootcamp...

Many Thanks to ConductRF for Continued Support!

ConductRF coaxial cables & connectors - RF CafeConductRF is continually innovating and developing new and improved solutions for RF Interconnect needs. See the latest TESTeCON RF Test Cables for labs. ConductRF makes production and test coax cable assemblies for amplitude and phased matched VNA applications as well as standard & precision RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the iBwave component library. They also provide custom coax solutions for applications where some standard just won't do. A partnership with Newark assures fast, reliable access. Please visit ConductRF today to see how they can help your project! 

Notable Tech Quote

Dunning–Kruger Effect Chart - RF Cafe"...Difficulties in recognizing one's own incompetence lead to inflated self-assessments." - Dunning-Kruger. The full title of the paper authored by David Dunning and Justin Kruger outlining what has become known as the Dunning–Kruger Effect is entitled, "Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments." In layman's terms, it could be put thusly: "The dumber a person is the more [s]he believes [s]he knows more than everyone else." This phenomenon can be seen all over social media and within the burning, looting, and mayhem protestor hordes terrorizing cities across the world. Of course it is also exhibited in politicians who try to rationalize the behavior and do nothing to prevent the wanton destruction of private and public property.

Mathematical Puzzles & Rainy Day Amusements, 1984 OFA

Mathematical Puzzles & Rainy Day Amusements, 1984 OFA - RF CafeFor as long as I can remember, The Old Farmer's Almanac (OFA) has included a set of Mathematical Puzzles in its annual publication. They range in difficulty from 1 (very easy) to 5 (sometimes quite difficult). Having been a faithful buyer and reader of the OFA for as long as I can remember, I have spent many hours toiling with some of the more challenging examples. In fact, there were a lot which I never did figure out and needed to look up the answers in the back (come to think of it, I experienced the same dilemma with my college engineering textbooks). Because quite a few of the Mathematical Puzzles are worthy of an engineer's cerebration, contemplation, and deliberation, they will all be eventually posted here...

RF Cascade Workbook 2018

RF Cascade Workbook 2018 Is Available Now! - RF CafeRF Cascade Workbook 2018 is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. Chances are you have never used a spreadsheet quite like this. It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed. An intro video takes you through the main features...

Many Thanks to MPDevice for Continuing Support!

MPDevice - RF CafeMPDevice (MPD) has become a trustworthy and reliable company in the global RF market as a manufacturer of passive RF devices. Included are attenuators and terminations, coaxial connectors, adapters, and cable assemblies, DC blocks, surge arrestors, power combiner / dividers, and directional couplers. The Korean Telecommunication market is now entering into the era of hyperconnected society. With continuous enhancement in R&D capabilities and quality control, MPD will continue in an effort to become the No. 1 technologically innovative company with a focus on the emerging 5G marketplace.

Wednesday 16

Mac's Service Shop: Magnetic Shielding

Mac's Service Shop: Magnetic Shielding, December 1955 Radio & Television News - RF CafeI have to admit to not knowing what an "Ouncer" audio choke was when reading this Mac's Service Shop story from a 1955 issue of Radio & Television News magazine. Research reveals that United Transformer Company produced a line of magnetic transformers and RF chokes weighing about an ounce (lightweight for its day), hence the moniker. They later made Sub−Ouncer products. Of course like just about everything else, they can still be purchased on eBay. Mac had been awed by a demonstration of the effectiveness of a new, low cost type of magnetic shielding that can be placed around a CRT to prevent distortion due to nearby magnetic fields created either within a chassis or from an external source. It is especially important for precision test equipment being used in a field-filled environment like an electronics repair...

Engineer Job Satisfaction Grows While Salaries Slows

Job Satisfaction Jumps for U.S. Engineers While Salary Growth Slows - RF CafeThe IEEE Salary & Benefits Survey 2020, reporting on 2019 data, has just been released. According to IEEE membership respondents, the typical technology professional earned $148,500 in 2019, excluding overtime, profit sharing, and side hustles, is up 2.4% over 2018 (less than the 4.5% increase in 2017). Overall job satisfaction broke over the 1.0 mark for the first time since the survey began in 2010. The consumer electronics sector fared the best in average salary at$185k, while aerospace & space followed at $180k. Education and machine learning did worst, but still were well over $100k. Benefits, bonuses, stocks, etc., can add significantly to the value. It will be interesting to see how things pan out for 2020 due to the Wuhan Virus epidemic.

Understanding Electron Transport in Graphene Nanoribbons

Understanding Electron Transport in Graphene Nanoribbons - RF Cafe"Graphene is a modern wonder material possessing unique properties of strength, flexibility and conductivity whilst being abundant and remarkably cheap to produce, lending it to a multitude of useful applications - especially true when these 2-D atom-thick sheets of carbon are split into narrow strips known as Graphene Nanoribbons (GNRs). New research published in EPJ Plus, authored by Kristians Cernevics, Michele Pizzochero, and Oleg V. Yazyev, Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland, aims to better understand the electron transport properties of GNRs and how they are affected by bonding with aromatics. This is a key step in designing technology such chemosensors..."

He Makes What We Hams Use - Art Collins

He Makes What We Hams Use - Art Collins, June 1953 QST - RF CafeArthur (Art) Collins, who began his radio career as a Ham, founded Collins Radio in 1933, in Cedar Rapids, Iowa. Just as civil aviation enthusiasts long ago began associating Wichita, Kansas, with Cessna, Lear, Beechcraft, et al, and its airplanes, radio people associate Cedar Rapids with Collins Radio. In fact - and this is a fact - electronics companies like RF Micro Devices (now Qorvo) and Skyworks Solutions set up RFIC design centers there back in the early 1990s in order to exploit the availability of highly talented engineers who worked for Collins. It was a time when defense industry contracts were winding down and cellphones were winding up...

Withwave Introduces Flexible Microwave "W−Absorber" Sheet

Withwave Introduces Flexible Microwave Absorber Sheet - RF CafeWithwave's W−Absorber is microwave absorber in thin sheet format made of a mixture of polymer resin and metal magnetic powder which is thin and flexible and excellent in workability and can be easily bonded. This absorber can suppress radiation noise of electronic devices for wideband microwave frequency range and reduce surface current as well as surface reflection in cavity resonant application. W−Absorber can suppress radiation noise of electronic devices for wideband radio frequency range and is effective in reducing surface current as well as surface reflection in cavity resonant applications due to the high magnetic loss characteristics of materials...

Many Thanks to Withwave for Continued Support!

Withwave RF & Microwave Components - RF CafeWithwave manufactures an extensive line of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch, board edge, panel mount), calibration kits (SOLT), a fully automated 4-port vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures for calibration and multicoax cable assemblies. Frequency ranges from DC through 110 GHz. Please contact Withwave today to see how they can help your project succeed.

Tuesday 15

Analog Computers Solve Complex Problems

Analog Computers Solve Complex Problems, November 1951 Radio & Television News - RF CafeCharles Babbage's 19th century Difference Engine might be considered the beginning of complex mechanical calculators' use in science and engineering. It really was not all that long ago. Massive single-purpose analog computers were designed and constructed in the middle of the last century for calculating, among other things, projectile trajectories, multi-body orbits, electrical circuit functions, nuclear detonations, calculation of mathematical function tables, and navigation. Eventually electrical computers joined the arsenal of tools available to significantly reduce the amount of time required to carry out complex calculations requiring multiple iterations using a range of input variables. Programmable vacuum tube and then transistorized digital computers expanded the range of applications, but recall that even by the early 1960s, during the early manned space flight projects...

Triad RF's HPA Helps Improve Counter UAS Responses

Triad RF Systems High-Power Amplifier Helps Improve Counter UAS Responses - RF CafeIn reaction to the need for better enabled Counter-UAS (CUAS) systems, Triad RF has recently added to their family of commercial-off-the-shelf (COTS) wideband high power amplifiers. The new TA1264 model weighs in at just 16 ounces, measures under 4" square and under 1" in height, and operates across the broad frequency range of 300 MHz to 6 GHz while delivering high power density, and optimal linearity and efficiency. The TA1264 is ideal for critical electronic warfare system applications, from simple CW/FM signals to highly modulated carriers such as 64 and 256QAM for software defined radios (SDRs), and general-purpose RF/microwave amplification. As a family, Triad RF's line of wideband...

"-Tron" Teasers - An Electronic Quiz

"-Tron" Teasers - An Electronic Quiz, October 1963 Electronics World - RF CafeThyratrons, klystrons, and magnetrons I've heard of, but trochotrons, charactrons, tonotrons I ain't heard of. That made this quiz more of a learning exercise for me than a test of any sort of knowledge possessed. Heck, I thought an 'ignitron' was a pejorative term for a really dumb techie wannabe. In all there are 17 types of '-tron' devices given for which to match from a list of descriptions. You'll probably do better than I did on this quiz that appeared in the October 1963 issue of Electronics World magazine.

Rent, Lease, or Buy Electronic Test Equipment?

Rent, Lease, or Buy Electronic Test Equipment? - RF Cafe"Evolving technology, certifications, and time are just some of the points to consider before renting, leasing, or buying that next piece of equipment. Whether you are a startup, mid-size business, or a large company, a smart approach to acquiring expensive electronic test equipment is the key. For every technology-driven business, it's a major concern to strike a tradeoff between high cost, constant maintenance, and calibration of new equipment vs. the need to conserve cash by renting or leasing. Should you rent, lease, or buy?"

Please Welcome PCBONLINE as Our Newest Sponsor

PCBONLINE - RF CafePCBONLINE supplies complex rigid and flex-rigid printed circuit boards (PCBs),and one-stop production with maximum flexibility ranging from prototype sample to mass production. Rigid-flex, HDI, multilayer, IC-loadboard, LCP 5G optical module, ceramic, MCPCB. Materials include Rogers, Taconic, Arlon, Isola, Bergquist, Kapton, Panasonic, and more. After more than 15 years of continuous efforts, PCBONLINE constantly updates our equipment, improves our technology, and serves you with the highest quality. Cost and delivery quotations online without the need for multiple phone call and/or e-mails.

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