Homepage Archive - June 2020 (page 3)

Friday 19

Electronics-Themed Comics from May 1947 Radio-Craft

Many topics of the electronics-themed comics which appeared in Radio-Craft were suggested by the magazine's readers. Staff artists like Frank Beaven turned those suggestions into cartoons. For a while there was a special feature called "Radio Term Illustrated" where, as the name suggests, terms like "Signal Generator" and "High Potential" are rendered in farcical form. These four comics, two of each type, appeared in a May 1947 issue of Radio-Craft. I have to admit that even with my familiarity with vintage electronics memes I do not get the Television "Organ" comic (yes, I understand the organ grinder, but not how it applies to TV).

Fractional Electronic Charge Observed in Topological Insulators

"The charge of a single electron, e, is defined as the basic unit of electric charge. Because electrons - the subatomic particles that carry electricity - are elementary particles and cannot be split, fractions of electronic charge are not normally encountered. Despite this, researchers at the University of Illinois at Urbana-Champaign have recently observed the signature of fractional charges ranging from e/4 to 2e/3 in exotic materials known as topological crystalline insulators. The team of researchers, led by mechanical science and engineering professor Gaurav Bahl and physics professor Taylor Hughes, has been using ultra high frequency electric circuits to study topological insulators since 2017..."

ConductRF Lab Small Flexible RF Cables

"ConductRF-Small-Flexible-RF-Test-Cables-6-19-2020.htm" target="_top"> Component Engineering challenges often require finding a "commonly available solution," for a specific application that meet broad, often conflicting requirements, determined by colleagues in electronics. Assuming knowledge of standards like "ConductRF-Small-Flexible-RF-Test-Cables-6-19-2020.htm" target="_top"> RG cables and widely available solutions, our expertise can be useful when those will not work. ConductRF can provide options for higher frequency, lower loss, greater mechanical integrity and more. When working in tight spaces, try these new RF cable options available exclusively from ConductRF. Costs & Lead Times Maintained Because these new cables are derived from older standards, ConductRF has been able to make minor changes to existing standard connectors. Changing crimp ferrules or re-purposing designs for other cables has allowed us to make many standard connectors available for producing assemblies...

Who Invented Radar?

A few years ago, RF Cafe visitor Cornell Drentea, KW7CD, submitted a short paper entitled, "Who Invented Radar?" I just updated the page to fix broken hyperlinks and figured it is worth posting again. I won't spoil his conclusion / assertion by telling you here. Mr. Drentea begins: "Whenever thinking of Radio, we usually think of one man: Guglielmo Marconi. Radar, on the other hand resulted from the work of many men. In 1793, the Italian scientist Lazzaro Spallanzani, a professor at Padua University studied the ability of blind bats to navigate using ultra sound. He observed that bats flew well in the dark without the aid of vision. He then designed a unique experiment to demonstrate the use of the bat's ears and concluded that a bat would become disoriented without its hearing. He concluded that the bats produced a continuous train of sound pulses and suggested that the rate of these pulses increased as a bat approached objects. This was not proven until..."

Interpreting Datasheet Data When Selecting Parts

Look deeper into those shiny front-page "sheet" specs - and search out the truly relevant data - to see if the part really is the best option for your application. Tejaswini Anand   "All that Glitters Is Not Gold: Interpreting Datasheet Data When Selecting Parts" "Application engineers often repeatedly answer the same questions from different customers, especially queries related to choosing parts in their application. One mistake we see in part selection happening time and time again is that the customers become over enamored by what I like to call 'the sheet' in data sheets. I'm talking about the shiny, glittery, sexy specs. 'Wow! That ADC has a high SNR!' This is the story of one such customer who was impressed with one analog-to-digital converter's (ADC) high signal-to-noise (SNR) but who forgot to consider other important datasheet specs. We will also address common mistakes and how to choose the right parts for your application."

Withwave: RF & Microwave Components

Withwave 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.

Thursday 18

MLinkPlanner 2.0 Wireless Planning Software Released

"MLinkPlanner-Center-Telecommunication-Technologies-6-15-2020.htm" target="_top"> Center of Telecommunication Technologies is proud to announce immediate availability of their "MLinkPlanner-Center-Telecommunication-Technologies-6-15-2020.htm" target="_top"> MLinkPlanner 2.0 wireless network software simulation tool for modeling microwave point-to-point (PtP) and point-to-multipoint (PtMP) links. The new version is free for current MLinkPlanner users. MLinkPlanner was created by engineers with many years of experience in designing microwave links, from single hop access links to high-power long-haul trunk lines. MLinkPlanner has demonstrated its effectiveness in designing many links that are operating successfully in various climate zones and topographical conditions from plains and marshlands to highlands. Special focus was placed on devising a convenient user interface, the incorporation of adaptable and easy to use link path profiles in the design process...

Focusing a Parabolic Disk

Paul Wade, W1GHZ, has a great article entitled, "Focusing a Parabolic Disk," in the June 2020 issue of the ARRL's QST magazine (p54). It discusses how to properly position a feed horn at the focus of a parabolic antenna dish, and presents plots of how various misalignments affects the signal quality. The motivation was determining how sensitive feed horn placement based on a near field test setup affects performance in the far field. Equations for the plots are not provided; however, Mr. Wade does include the Rayleigh distance (D_R) formula for antennas of D_R = 2D²/λ, which is the transition distance from near field to far field - the Fresnel and Fraunhofer regions, respectively. Unfortunately, you need an ARRL member login to access the article, but if you don't have one, find a nearby Ham and ask to borrow his hard copy. BTW, the June 2020 cover has to be the ugliest thing ever published on QST.

His Mentor's Mentor Was Major Armstrong

RF Cafe visitor Mike M. sent this very interesting note after reading this "Frequency Modulation Fundamentals" article: Again, you hit it out of the ballpark, Kirt! Great article out of QST. Absolutely accurate to credit "The Old Man" Edwin Armstrong for the invention/development of FM and much more, plus the work of Dan Noble, who worked with the Connecticut State Police and Motorola as Director of Research. Also many, many others. Some that have never been properly credited. Guys like Bob Morris, W2LV and Frank Gunther, W2ALS. They were both interviewed by Ken Burns for "Empire of the Air". I was fortunate enough to talk to both of these guys after I got my Tech license in 1970. My immediate supervisor/mentor from 1972 until he retired in ~1990, was George. He was a superb mentor, who espoused the best engineering methods and as he would say " the price of success is constant vigilance." George had worked for Armstrong at the pioneering FM station, W2XMN in the late 40's and early 50's. George had several stories about working for "The Old Man..."

Alaris USA Added to Antenna Vendor Page

Ralph Prigge, of Alaris USA, wrote to request that his company be added to the list of companies on the RF Cafe Antenna Vendors page. Alaris USA is an organization based in Maine to sell products of COJOT, mWAVE and Alaris Antennas to their customers in the USA. All are sister companies owned by Alaris Holdings Limited (formerly Poynting Antennas) headquartered in South Africa. They design, manufacture and distribute antenna products for the global defense, homeland security and specialized antenna market sectors, including international electronic warfare (EW) system houses and also include semi- and governmental organizations. Alaris USA is proud to provide our American customers specialized military and defense products including EMC, tactical communications, vehicle-mounted, fixed site, switched beam, direction finding, and mission adaptive antennas. Please check Alaris USA out today if you have antenna needs.

Are Quantum-Tunnel Transistors Real?

Now that the wonder material graphene and the wonder wireless communications scheme of 5G has had their respective heydays, much attention is being given to quantum computing and quantum-tunnel transistors. "Quantum," which already had its own heyday back in early last century, is in vogue again - like wide ties, big-framed eyeglasses, and miniskirts. Lee Goldberg has a piece titled "Are Quantum-Tunnel Transistors Real, and What Do They Mean for Power Tech?" posted over on the Electronic Design website in case you are interested in learning about the latest happenings in the field of quantum-tunnel transistors. They actually have nothing to do with quantum computers, and get their name due to tunneling effects (a la the familiar tunnel diode) that are exploited in this new "Bizen" phenomena that is being touted as a replacement for CMOS ICs. Time will tell how accurate the prediction is, as with the recently mentioned Wamoscope.

TotalTemp Technologies: Thermal Platforms for -100°C to +200°C

TotalTemp Technologies has more than 40 years of combined experience providing thermal platforms. Thermal Platforms are available to provide temperatures between -100°C and +200°C for cryogenic cooling, recirculating circulating coolers, temperature chambers and temperature controllers, thermal range safety controllers, space simulation chambers, hybrid benchtop chambers, custom systems and platforms. Manual and automated configurations for laboratory and production environments. Please contact TotalTemp Technologies today to learn how they can help your project.

Wednesday 17

Electronics Physics Quiz

Robert Balin created many quizzes for Popular Electronics magazine during the 1960s and 1970s. Topics included series circuits, electrochemistry, electronic analogy, electronic coupling, electronics analogy, audio, electronic units, capacitor circuits, AC circuit theory, magnetic phenomena, electronics geography, electronic noise, plugs and jacks, electronic switching, diodes, and many more. This "Electronics Physics Quiz" is the 59th that I have posted. It challenges you to name the effects that were first noticed as the result of unexpected actions during laboratory experiments. Many of the names, as you might expect, eponymously honor their progenitors. My score was 80%.

Samsung Galaxy S20TE Smartphone for Communications on Battlefield

"Upgrades include a mode for use while wearing night-vision goggles, and a stealth mode that disables LTE and mutes all RF broadcasting. The handset has undergone a series of changes to make it a piece of military-grade tech. In addition to being packed into a case that looks like it could withstand a nuke, the S20 TE features DualDAR architecture that secures data with two layers of encryption and is based on NSA standards. With communications being a vital element of a field operative's work, Samsung says the S20 TE comes with pre-configured software to support tactical radios and mission-critical devices through the use of Private SIM, 5G, Wi-Fi 6 and CBRS (Citizens Broadband Radio Service) -- a band of radio-frequency spectrum from 3.5 to 3.7 GHz..."

Tubes: Luckily, They're Still Around

Just in time for the birthday of vacuum tube pioneer Sir William Crookes, Lou Frenzel has an article titled "Tubes: Luckily, They're Still Around" on the Microwaves & RF website. "As Noah said to his family after dinner, 'Those unicorn steaks were excellent!'" "So, unicorns are gone for good. But not vacuum tubes. It doesn't seem that tubes will ever disappear completely - they're still with us and that's a good thing. I was reminded of that several times over the past weeks. For example, I was scanning the ads for a high-power ham-radio amplifier. Most of the popular transceivers top out at about 100 W. For good long-distance (DX) communications around the world on the high frequency bands (3 to 30 MHz), more power is desired. A number of companies make accessory power amps to boost power level to the FCC legal limit of 1500 W. Both transistor and tube models are available to choose from. The solid-state amps use multiple RF MOSFETs to get to levels of 500 to 1000 W. These are very expensive..."

An Electric Wristwatch

The world's first electric wristwatch went on sale on January 3, 1957 - the Ventura model, by Hamilton Electric, and it retailed for $200. I use the event as the theme of the RF Cafe logo for that day in history. Unlike today's electric watches which use a crystal for timing, the early watches used a pulsed motor to energize the balance wheel coil, in place of a mainspring and an escapement mechanism. Some "atomic" wristwatches today like the Casio Waveceptor (<$40) use the WWV signals from Boulder, Colorado, to synchronize the time with world standards. The watch shown in this article from the February 1958 edition of Radio-Electronics magazine is a model 500, which you can find more detail about on the Unique Watch Guide website...

Measurements with Scattering Parameters

Joe Cahak, owner of Sunshine Design Engineering Services, has submitted another fine article for posting here. Joe has many years of automated RF testing experience to leverage when writing this paper on making measurements with scattering parameters (S-parameters) involved. He begins, "In many RF and Microwave measurements the S-Parameters are typically expressed in dB (decibels) Magnitude units and Degrees in the polar coordinate system. Network and Vector Network Analyzers and Spectrum Analyzers all measure with voltage ratio measurements, so to convert to dB in terms of volts we must use the following equation. The Spectrum Analyzer is a frequency discriminating detector that detects the voltage for the signal. It will give the amplitude of signal as a function of frequency. It is scalar in measurement dimension magnitude vs. frequency. Displayed units are typically expressed in units of power (dBm). The Vector Network Analyzer measures complex magnitude and angle of RF signals vs. frequency. By using reference signals to calibrate the test system response and setting up a reference frame for the measurements, the instrument can measure the amplitude and phase angle of the AC-RF signal for each frequency it is tuned to. Displayed units are typically expressed..."

Qorvo / Custom MMIC: Off-the-Shelf and Custom MMICs

Qorvo / Custom 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 Qorvo / Custom MMIC today to see how they use their modern engineering, testing and packaging facility to help your project. 

Tuesday 16

Cannon Electric Sub-Miniature Plugs

According to the Wikipedia entry, Cannon Electric Company introduced the now-familiar D-Sub (D-subminiature) connector format in 1952. This advertisement in a 1954 issue of Radio & Television News magazine is the first one I recall seeing. D-Sub connectors were a really big deal back in the 1980s when personal computers (PCs) first appeared. CRT monitors used them, printers used them, scanners used them, network interfaces used them, mice and keyboards used them (those that didn't use PS/2 connectors, which were an invention of IBM for their Personal System 2 computers). Nowadays the USB (Universal Serial Bus) and HDMI (High-Definition Multimedia Interface ) connectors have replaced most D-Subs in the computer cable realm. Of course with everything going wireless, connectors and cables of all sorts are rapidly disappearing except those used for charging...

New U.S. Semi Fab: Reality or Illusion?

"Official talks on construction and operation of a new TSMC semiconductor chip manufacturing fab the in U.S. is promising but riddled with political and technical intrigue. Will the news of a new semiconductor fab on U.S. soil be a boost to the economy and technological stability or is it merely a fanciful political scheme? To answer that question, let's start with the news that has created so much discussion in the electronics space. Recently, the Taiwan Semiconductor Manufacturing Company (TSMC) announced its intention to build and operate an advanced 5nm semiconductor fab in the U.S. state of Arizona. TSMC, headquartered in Taiwan, is the largest chip manufacturer in the world. The company currently operates a fab in Camas, Washington and design centers in both Austin, Texas and San Jose, California. The Arizona facility would be TSMC's second manufacturing site..."

The 'Wamoscope' - a Picture Tube That Includes Many Functions

Yeah, I thought the same thing... a "Wamoscope?" Was it produced by the Wham-O toy company that makes the Hula Hoop, the Frisbee, the Super Ball, and Silly String? Wham-O was founded in 1948, and this article appeared in a 1956 edition of Radio & Television News magazine, so why not? Actually, Wamoscope is derived from "WAve-MOdulated oscilloSCOPE." Developed by Sylvania Electric Products, it combined a traveling-wave tube with a cathode ray tube in single enclosure. That enabled microwave signals to be fed directly to the CRT for amplifications and processing. Evidently the idea did not catch on since the market was never filled with Wamoscope sets. A brochure for Sylvania's 6762 Wamoscope is shown at the bottom of the page...

Please Welcome Berkeley Nucleonics as the Newest Sponsor!

Berkeley Nucleonics Corporation (BNC) is a leading manufacturer of precision electronic instrumentation for test, measurement, and nuclear research. Founded in 1963, BNC initially developed custom pulse generators. We became known for meeting the most stringent requirements for high precision and stability, and for producing instruments of unsurpassed reliability and performance. We continue to maintain a leadership position as a developer of custom pulse, signal, light, and function generators. Our designs incorporate the latest innovations in software and hardware engineering, surface mount production, and automated testing procedures ...

Aspects of 6G That Will Matter to Wireless Design Engineers

If 5G began life as and still does to many people remain a nebulous concept, then the definition of 6G is really up for grabs. This article on the EDN website by Jessy Cavazos, titled "Aspects of 6G That Will Matter to Wireless Design Engineers," is one of the first attempts I've seen to explain it. Here is her summation: "In addition to the next-level evolution in automated driving and smart manufacturing, 6G will enable innovative applications by combining sensing, imaging, and precise timing with mobility and truly leveraging artificial intelligence (AI) and intelligent networks. Further integrating communications technologies into society, 6G technology will bring mixed reality experiences and telepresence to life, while playing a pivotal role in achieving global sustainability, improving society, and increasing productivity across industries."

Nova Microwave: RF & Microwave Circulators & Isolators

Nova Microwave is a leader in technically differentiated electronic and radio frequency Ferrite Circulators and Isolators that connect, protect and control critical commercial and military wireless telecommunications systems. Our staff is dedicated to research and development of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz to 26.5 GHz. Available in single or multi-junction topographies, the Nova Microwave product line of is specifically designed for use in varied environmental and temperature extremes. 

Monday 15

Walsco Electronics Corporation Antennas

This is another example of one of those advertisements you likely would not see in a modern electronics magazine. There is nothing fundamentally problematic about its content or message, but politically correct standards would condemn any depiction of a woman expressing such excessive appreciation for a man's efforts. It might, after all, convey the idea that all television antenna servicemen should expect such treatment from all women. It also implies that only men can be TV antenna servicemen / servicepersons. If that sounds nutty, well, what can I say. It's the world we live in as evidenced by news items of late. Keep firmly in mind that what is accepted as a social norm today might be considered to be a crime in a few decades, so exercise caution in all you do in the presence of witnesses be it written, videoed, spoken, or acted out...

Spherical Solar Cells Soak up Scattered Sunlight

"Silicon solar cells folded into spheres hint at solar power's flexibility in even small devices. Flat solar panels still face big limitations when it comes to making the most of the available sunlight each day. A new spherical solar cell design aims to boost solar power harvesting potential from nearly every angle without requiring expensive moving parts to keep tracking the sun's apparent movement across the sky. The spherical solar cell prototype designed by Saudi researchers is a tiny blue sphere that a person can easily hold in one hand like a ping pong ball. Indoor experiments with a solar simulator lamp have already shown that it can achieve between 15% and 100% more power output compared with a flat solar cell..."

RF Cafe Visitor Dave H. Comments on Early Mobile Communications

RF Cafe visitor Dave H. wrote to offer the following additional information about the history of mobile radio communications. It is fairly extensive, so it is posted at the bottom of the page. "I liked the article about Don Wallace and his car to home radio. I knew that in Detroit, the police had attempted to have car to car transmissions. They were not overly successful however. They did implement a station to car, 1 way transmission. I discovered the facts about the Detroit police radios while researching a paper that I wrote entitled: 'SAW Filters : The Unsung Heroes of the Cell Phone Revolution.' Did you know that that the phone developed by Martin Cooper while at Motorola, circa 1973, had a filter board that measured 10 inches by about 1 inch? That would be a tad hard to find..."

WWV Moves to Colorado

This is the first of a two-part series on the move of the WWV transmitter stations operated by the National Bureau of Standards (now called National Institute of Standards and Technology) from Greenbelt, Maryland, to Boulder, Colorado. WWV Part II appeared in the February 1967 edition of the ARRL's QST magazine. WWV began transmitting time / frequency standards in 1920 in order to provide a means for remote stations and laboratories to calibrate local standards that would prevent transmitting stations from interfering with each other. Although most people don't realize it, the 60 kHz signal that their 'atomic' clocks and watches use to self-adjust time emanates from the WWVB antenna in Boulder. This first installment of the article discusses the history and rationale for relocating the WWV facility to a new location. The second part gets into the technical aspects...

Triad Helps High Altitude Platform Leader Achieve Stratospheric Flight Test Success

"triad-rf-systems-high-altitude-platform-stratospheric-flight-test-6-11-2020.htm" target="_top"> When an industry-leading provider of stratospheric communications platforms first called on "triad-rf-systems-high-altitude-platform-stratospheric-flight-test-6-11-2020.htm" target="_top"> TRIAD RF Systems, they were initially looking to gain an incremental wireless communications range boost. What they achieved instead was a mission that went from an underwhelming link performance test to an incredible long-range success in under 5 minutes. The Challenge: Filling the capability gap between aircraft, drones and satellites, this industry-leading platform designer and manufacturer delivers solutions for communications, data relay, and intelligence, surveillance, and recognizance (ISR) applications to space agencies, the military, communications providers, and many other commercial applications. The customer simulated that the link distance without a TRIAD power amplifier would be approximately 100 miles. However, at a distance of 75 miles away from the base station, the link started to cut out, and all communication was lost...

PCB Directory: Printed Circuit Board Fabrication & Assembly

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 (FR-4, Rogers, flexible, rigid), Geographical location (U.S., China), kinds of services (manufacturing, fabrication, assembly, prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.

Sunday 14

Amateur Radio Crossword Puzzle for June 14

Each 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. In this crossword for June 14th 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!

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. Some quoted items have been shortened to save space. About RF Cafe.

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