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Homepage Archive - January 2021 (page 2)

See Page 1 | 2 | 3 | 4 | 5 of the January 2021 homepage archives.

Thursday the 14th

Sprague Trading Post

Sprague Trading Post, August 1945 Radio-Craft - RF CafeHave you been looking for a Zenith Radio Nurse, a Superior Speedometer Multitester, or maybe a Clough Brengle 3" Oscilloscope? Perhaps you happen to have a wireless phono oscillator, a Weston 722 radio, or a Dumont 3" model 164E oscilloscope for sale. In either case, the Sprague Trading Post would have been the place to go in the mid 1940s, when the company paid good money in Radio-Craft magazine to host a swap shop for electronics hobbyists and professionals. Vacuum tubes, radios, test equipment, and related items were offered and requested. Sprague was/is a major manufacturer of capacitors, so they probably figured some of the equipment would need replacement capacitors which traders would buy from them...

Over-the-Air (OTA) Testing

Over-the-Air (OTA) Testing (R&S) - RF CafeRohde & Schwarz has a downloadable whitepaper entitled, "Over-the-Air (OTA) Testing - Important Antenna Parameters, Test System Setup and Calibration." Future technologies and standards will make over-the-air (OTA) testing mandatory. At the same time, integrated antennas are becoming more common with each development cycle such as for low-cost IoT devices and 5G mmWave devices. Since measurement requirements will change with OTA testing, engineers need a basic understanding of antennas and antenna measurements. This paper provides you with extensive knowledge on the following: Antennas in general, their parameters and different types, as well as antenna characterization and testing The importance and execution of OTA test setup calibration...

Webinar: Designing PCBs 5x Faster Despite the Pandemic

Designing PCBs 5x Faster Despite the Pandemic - RF Cafe"Join our webinar on January 20th, to learn how Kinetic Vision uses Altium's platform to enable a connected and frictionless PCB design experience, increasing their productivity x5 even in the midst of Covid. For over 30 years, Kinetic Vision has provided technology solutions to over 50 of the top Fortune 500 companies in the world. Hear about how their embedded development team needed a better design and collaboration solution to satisfy the increasing needs of their demanding clients and how Altium helped solve their toughest issues. Altium Designer is their tool of choice when it comes to designing PCBs, as it provides the most connected PCB design experience - removing the common points of friction that occur throughout a typical design flow. With the Covid situation, using Altium's platform became even more essential as it enabled seamless remote working..."

Radio-Craft Incorporating Radio & Television

Radio-Craft Incorporating Radio & Television, November / December 1941 Radio-Craft - RF CafeThe announcement of the merging of Radio-Craft and Radio & Television magazines into a single publication was made on the eve of America's entrance into World War II. Knowing the visionary talents of publisher Hugo Gernsback, he probably did so at least partly due to what could be predicted as a severe contraction of the domestic electronics appliance market once the war machine gears began cranking. It turns out that he was in fact prescient, because history shows that the government did direct all critical production to military equipment. Buying a new model radio, television, washing machine, and to some extent car grew increasingly difficult from about 1942 through 1945...

Guerrilla RF GRF5508/10 ¼W PAs w/Ultimate in Native Linearity

Guerrilla RF GRF5508/10 ¼W Power Amplifiers Deliver the Ultimate in Native Linearity - RF CafeGuerrilla RF introduces the GRF5508 and GRF5510, two of ten new ¼ W linear power amplifiers being released as part of the company's expansion into the cellular market. These new InGaP HBT amplifiers were designed specifically for 5G/4G wireless infrastructure applications requiring exceptional native linearity over temperature extremes of -40°C to 85°C. Spanning frequency ranges of 800-900 MHz and 880-960 MHz respectively, the GRF5508 and GRF5510 are tuned to operate within the n5, n8, n18, n20 and n26 5G new radio (NR) bands. The devices can deliver 24 dBm of linear power over the entire -40°C to 85°C temperature...

Thanks to Copper Mountain Technologies for Continued Support

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 the 13th

Du Mont "Duoscopic" Television Receiver

Du Mont "Duoscopic" Television Receiver, March 1954 Radio & Television News - RF CafeThe Duoscope, as presented in a 1954 issue of Radio-News magazine, was a pretty neat concept - sort of like a picture-in-picture (PiP) scheme for television, only in a way much better. Whereas PiP provides only a partial screen for each television program, Du Mont's "Duoscopic" viewer somehow received two independent signals and combined them on the screen in such a manner that there was both a horizontally polarized for one show and a vertically polarized image for the other. The viewer selected which picture to watch by wearing the appropriately polarized glasses or by watching through a floor-mounted transparent, polarized screen. The superimposed image on the CRT looked a lot like a virtually indiscernible 3-D picture as seen without colored glasses. Similarly, the audio for each program was selectable using a remote (wired) switch box. Headphones were used to provide private listening. The Duoscope turned out to be just another "outside the box" concept that never played out in the consumer world...

Withwave End Launch 1.0 mm Connector for DC - 110 GHz

Withwave End Launch 1.0 mm Connector (Narrow Block) for DC to 110 GHz - RF CafeWithwave's new End Launch 1.0 mm (Narrow Block) coaxial connectors are specially designed for well used high frequency substrates to minimize electromagnetic effects including impedance discontinuities from coaxial to GCPWG (Grounded Coplanar Waveguide) and Top Ground Microstrip structure. The types of connectors are 2.92 mm, 2.4 mm, 1.85 mm & 1.0 mm. Applications include RFIC Chip set evaluation boards, high data rate ASIC and SoC evaluation module test, and substrate characterization.  We solve your performance and cost problems.

China Testing NextGen Wireless Technology Using THz Waves

China Testing NextGen Wireless Technology Using THz Waves - RF Cafe"While most of the world is still using the 4G networks and some companies have just released 5G networks, China is testing next-generation wireless technology that is said to be 100 times faster than the American version of 5G. This next-generation network expands from the 5G millimeter-wave frequency to terahertz frequency. The 5G network promises mass connectivity, ultra-reliability, and guaranteed low latency. However, there is a limit to what 5G can do until 2030 and beyond. New Chinese research has outlined four major paradigm shifts that are needed for a next-generation network. The long-form review is entitled "Towards 6G wireless communication networks: vision, enabling technologies, and new paradigm shifts..."

White Paper: Radio Fundamentals for Cellular Networks

Radio Fundamentals for Cellular Networks - RF CafeRohde & Schwarz recently published a white paper entitled, "Radio Fundamentals for Cellular Networks." It begins: "Cellular technologies have advanced from first generation (1G) analog technologies to advanced high performance fourth generation (4G) and fifth generation (5G) systems in just four decades. Despite the increase in complexity of wireless standards and devices, cellular technologies maintain a set of common principles that form the basis behind the design of cellular systems. In this white paper, we explore these basic principles and examine the underlying technologies that lay the foundation for today and future cellular systems." BTW, does anyone else think R&S's use of that light blue on a gray background is not a very good choice?

Audio Quiz

Audio Quiz, April 1955 Popular Electronics - RF CafeThere are a lot of audiophiles in the RF Cafe audience, so this 10-question Audio Quiz from Popular Electronics should prove useful. It covers not just the physical aspects but also some simple electronics concepts, like decibels of gain, crossover networks, push-pull amplifiers, etc. High fidelity (hi-fi) stereophonic equipment was all the rage in the 1950s and 1960s. It was a way for people to enjoy live concert quality music in their homes since the quality of radio transmissions was not reliable, and stereo broadcasting was not a common feature until the 1960s. Many articles were published educating beginners and veterans on ways to optimize both equipment - receivers, turntables, speakers, equalizers, etc. - and environmental parameters. Similarly, many stereo-themed comics (and here) appeared in Popular Electronics and other magazines. Enjoy.

Many Thanks to Atenlab for Their Continued Support!

Atenlab microwave components - RF CafeAtenlab has been operating in Taiwan for more than a decade, and has sold and installed hundreds chambers around the world. Holistic, affordable Over-the-Air (OTA) measurement systems perform comprehensive measurement and test in a controlled environment. Compact Antenna Test Range (CATR) with one-touch operation supports multiple systems - 2G, 3G, 4G, 5G - and major instrument brands. [M]ulti-probe OTA measurement systems offer reduced time measurements over single-probe systems.

Tuesday the 12th

Meissner Manufacturing Company

Meissner Manufacturing Company, March 1944 Radio-Craft - RF CafeMeissner was one of many electronics manufacturers that re-tooled their facilities for defense production during the war years. They made RF coils and transformers (and a few radios). Company public relations offices were sure to make their contributions known to people who used their products and/or services. In this 1944 full-page ad in Radio-Craft magazine, Meissner touted its coveted Army-Navy "E" rating, awarded for "excellence" performance. According to the Wikipedia entry, only 2% of companies earned the distinction, so it really was a big deal. The term "precision-el" was used throughout Meissner promotions, and it took a bit of work to determine what it meant. Turns out precision-el (i.e., precisionel) is a play on personnel (i.e., personn-el). Such things were considered clever back in the day...

Engineering Documentation Methods Questionnaire

Engineering Documentation Methods Questionnaire, North Dakota State University - RF CafeRF Cafe visitor Michael Maassel, an electrical engineering professor in North Dakota State University's Electrical and Computer Engineering Department, requested that I post these few questions to help him effectively prepare students taking senior-level (aka "Capstone") design courses for a real-world experience after graduation. Says the good professor, "The biggest headache I have is getting the students to document their work, both in hardware and in software. Currently, I am requiring that the students use a quad line notebook. This has not been very successful." How do you handle documentation in your every-day work?

4D Imaging Radar Advances ADAS and Level 5 Automation

4D Imaging Radar Advances ADAS and Level 5 Automation - RF Cafe"The 'fourth dimension' improves radar accuracy in driver-assistance and self-driving systems. Several companies are pushing it forward with recent introductions. In contrast to cameras and LiDAR, 4D imaging radar uses echolocation and the principle of time-of-flight measurement to find things in its environment. It works well in all weather and environment conditions, including fog, heavy rain, and darkness. 4D imaging radar can tell when a car is moving and at what speed in a full white-out snowstorm. It also has the benefit of sensing out to 300 meters - a requirement for higher levels of automation. 4D is called 4D because it's a high-resolution long-range radar sensor that not only detects the distance, relative speed, and azimuth..."

The Aircraft Radio Serviceman

The Aircraft Radio Serviceman (Piper Cub), April 1946 Radio News - RF CafeAircraft electronics has always been on the bleeding edge of technology because of the ever-increasing need to fly in the widest range of atmospheric conditions possible. Accordingly, skills needed by avionics servicemen are amongst the highest required in any electronics field. There are still many pieces of vintage equipment in service that need to be maintained, but even 20- to 30-year-old airborne radars and navigational units require top-notch techs to troubleshoot and align. One topic in particular that plagues electronics operation even in modern airframes is that of static electricity build-up and lightning strikes. We all face those kinds of static discharge hazards in non-aviation environments, but for the most part a failure on the ground or water is not as imminently life-threatening as a failure in the air...

What's the Difference Between EMF and Voltage?

What's the Difference Between EMF and Voltage? - RF CafeWhenever I see John Dunn's name I think of the English poet John Donne, but that's my problem. Mr. Dunn wrote an article for EDN magazine entitled, "What's the Difference Between EMF and Voltage?" He begins: "I once read this very strongly-written essay about the difference between electromotive force (EMF) and voltage. The author seemed like he was on some kind of holy crusade and was intensely determined to set his readers straight on fundamental truths that were NOT to be dismissed by infidels. I read his words, but for all of the vitriol, I didn't understand him at all. Recently, I decided to take a closer look at the issue. EMF is given in units of joules per coulomb. The frame of reference for this definition is for any device that uses a non-electrical source of energy to impart electrical energy to a unit of charge, which if given the chance, will flow somewhere..."

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.

Monday the 11th

Electronics-Themed Comics

Electronics-Themed Comics, November 1947 Radio-Craft - RF CafeDo you detect any (probably unintended) irony in the page 76 comic from a 1947 issue of Radio-Craft magazine? It shows a husband and wife shopping for a new radio and has the husband telling the salesman, "I don't care if it is FM - I want one that plays in the P.M.!" I'll let you think on it for a moment. As with many of the comics that appeared in the magazine, the scenarios were suggested by readers. The other comic played on the common music programming schedule that included times of "dinner music," "evening music," etc. If you like these comics, then you'll appreciate the huge list at the bottom of the page of others with tech themes.

Qorvo Industry-Leading LNAs for 5G Base Station Deployments

Qorvo® Introduces Industry-Leading Low Noise Figure LNAs Enabling 5G Base Station Deployments - RF CafeQorvo, a leading provider of innovative RF solutions that connect the world, today introduced a family of high-performance low noise amplifiers (LNAs) tailored for base station infrastructure deployments including 5G massive MIMO (m-MIMO). Qorvo's newest family of LNAs combines the lowest noise figure in the industry - 0.3 dB achieved at 2 GHz - with unmatched reliability and scalability in a very compact footprint. The flagship QPL9547 LNA utilizes Qorvo's latest generation enhancement-mode pseudomorphic High Electron Mobility Transistor (pHEMT) process to provide market-leading noise figure and improved receiver sensitivity for cellular base stations. This LNA is internally matched and is available...

Quantum Microwave mm-Wave Components

Quantum Microwave mm−Wave Components - RF CafeIf you are in the market for mm-wave waveguide components, you will definitely want to vist Quantum Microwave. They have a huge selection of active (18-110 GHz) and passive (18-325 GHz) components that are designed and manufactured right there in their Massachusetts facility! Attenuators, detectors, diplexers, power amplifiers, mixers, isolators & circulator, multipliers, antennas, switches, probe adapters, terminations, and filters. Waveguide sections include straight, bends, twists, transitions, and adapters. The star of the show, however, is their patented "GuideLock" connector system that eliminates screws and creates a superior joint. Check them out!

What Is an Audio Watt?

What Is an Audio Watt?, August 1955 Popular Electronics - RF CafeMost of us that have any reason to visit RF Cafe know what a watt is both from a DC, Ohm's Law perspective, and from an RF power perspective. Some, though, are not quite sure what an audio watt is, as far as whether it is the same as a watt of DC power or a watt of AC power (sinewave or not?). This short article from the August 1955 Popular Electronics answers the question, including why it is necessary to drive speakers at what seems like unnecessarily high power levels given how sensitive the human ear is to sound...

Post Your Engineer & Technician Job Openings on RF Cafe for Free

/jobs.htm" target="_top"> Engineering Job Board - RF CafeRF Cafe's raison d'être is and always has been to provide useful, quality content for engineers, technicians, engineering managers, students, and hobbyists. Part of that mission is offering to post applicable job openings.. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge. 3rd party recruiters and temp agencies are not included so as to assure a high quality of listings. Please read through the easy procedure to benefit from RF Cafe's high quality visitors...

Thanks Once Again to everythingRF for Long-Time Support!

everything RF Searchable Database - RF CafePlease take a few moments to visit the everythingRF website to see how they can assist you with your project. everythingRF is a product discovery platform for RF and microwave products and services. They currently have 267,269 products from more than 1397 companies across 314 categories in their database and enable engineers to search for them using their customized parametric search tool. Amplifiers, test equipment, power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers, power supplies, and everything else. Please visit everythingRF today to see how they can help you.

Sunday the 10th

RF & Microwave Theme Crossword for January 10th

RF & Microwave Theme Crossword Puzzle for January 10, 2021 - RF CafeThis RF & Microwave Crossword Puzzle of 2021 has many words and clues related to engineering, mathematics, chemistry, physics, and other technical words. As always, this crossword contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

Friday the 8th

Fundamentals of Radio Servicing: Signals in Space

Fundamentals of Radio Servicing, January 1951 Radio-Electronics - RF CafeJohn T. Frye, creator of the "Mac's Radio Service Shop" and "Carl & Jerry" technodrama article series, employed his mastery of electronics to weave into tales valuable lessons in circuit design and troubleshooting, business practices, dealing with customers, test equipment usage, education, as well as introducing new technology. His columns ran for decades in multiple electronics trade and hobby magazines. In addition to that, Mr. Frye wrote many technical articles such as this "Fundamentals of Radio Servicing" piece that ran in a 1951 issue of Radio-Electronics magazine. It is Part 23 of a series and deals with "Signals in Space." An avid Ham operator, he is aware that it was radio amateurs who played a large role in early discoveries...

Werbel Microwave Intros 20 dB Coupler for 2 to 18 GHz

Werbel Microwave Intros 20 dB Coupler for 2 to 18 GHz - RF CafeWerbel Microwave, a designer and manufacturer of RF and microwave power couplers, dividers, terminations, and DAS equipment, introduces directional coupler model C-1182-20, a high performance wideband directional coupler that covers 2 to 18 GHz with 20 dB coupling and a typical flatness of ±0.45 dB. It has excellent return loss and low insertion loss. Usually in stock, but check website or call for availability. Werbel Microwave's catalog of directional couplers and power splitters / combiners are high performance at an affordable price point. Our original design, USA made.

The "Para-Talkie"

The "Para-Talkie", April 1945 QST - RF CafeThe first recorded successful parachute jump was made from a hot air balloon in 1797 by Frenchman André-Jacques Garnerin. His performance elicited "a scream of terror" from the crowd below and even caused women to faint at the sight of his basket swinging wildly beneath the canopy. Many brave souls met with less success before and after that jump. By World War II the state of the art for parachutes had managed to cure the wild swing problem, but reliability still left a lot to be desired, especially when the 'chutes were packed by paratroopers with only a few weeks of experience. Control during the descent was rather limited due to the original round configuration with directional commands effected by pulling on the shroud lines on one side or the other...

Atomic-Scale Nanowires Produced at Scale

Atomic-Scale Nanowires Produced at Scale - RF Cafe"Researchers from Tokyo Metropolitan University have discovered a way to make self-assembled nanowires of transition metal chalcogenides at scale using chemical vapor deposition. By changing the substrate where the wires form, they can tune how these wires are arranged, from aligned configurations of atomically thin sheets to random networks of bundles. This paves the way to industrial deployment in next-gen industrial electronics, including energy harvesting, and transparent, efficient, even flexible devices. Electronics is all about making things smaller - smaller features on a chip, for example, means more computing power in the same amount of space and better efficiency..."

Many Thanks to KR Electronics for Helping Deliver RF Cafe!

KR ElectronicsKR Electronics designs and manufactures high quality filters for both the commercial and military markets. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop and individually synthesized filters for special applications - both commercial and military. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. All common connector types and package form factors are available. Please visit their website today to see how they might be of assistance. Products are designed and manufactured in the USA.

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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