Friday 14

Mac's Radio Service Shop: The Time Is Now

Unlike many electronics enthusiasts including hobbyists, salesmen, servicemen, and commercial and domestic users, Mac McGregor was an early-on believer of the ultimate replacement of vacuum tubes by transistors. Only a decade old and not yet adopted by a lot of manufacturers (to their ultimate demise in some cases), transistors were fighting a major battle to gain acceptance and trust by the public. Not only were transistors still more expensive than an equivalent vacuum tube, but the reliability was not as good - most times due to designers not properly accounting for their special needs for protection against voltage extremes. Once the price of transistorized products fell into parity with their predecessors, consumers quickly adopted the products because of the markedly smaller sizes and lower power consumption...

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

RF 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 (of course a gratuity will be graciously accepted). 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...

Anatech Electronics February 2020 Product Update

"anatech-electronics-product-announcement-2-13-2020.htm" target="_top"> Anatech Electronics offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. In their "anatech-electronics-product-announcement-2-13-2020.htm" target="_top"> February Product Update, Anatech has introduced a surface mount 5245-5855 MHz cavity bandpass filter with 40 W power handling, a 5550 MHz (902 MHz bandwidth) cavity bandpass filter, and a surface mount 5400 MHz MonoBlock ceramic bandpass filter . Custom RF power directional coupler designs can be designed and produced when a standard cannot be found, or the requirements are such that a custom approach is necessary...

Curiosa in Radio

I usually try to post something a little less serious and technical on Fridays to help everyone wind down from the long week just passed. It could be a Carl & Jerry or a Mac's Radio Service Shop story, an electronics quiz, or even something I found out on the Internet. This time it is a "believe-it-or-not" type feature titled "Curiosa in Radio," about radio manufacturing, operating, and infrastructure. One factoid claims "Only 1.1% of set manufacturers in business in 1924 are building sets today." It could due to being in the middle of the Depression Era so almost nobody was making / buying radios, but more likely it reflects the reality of the many people who jumped into the fledgling radio industry early on and then could not gain market share. Enjoy.

Mathematician Solves Boolean Sensitivity Conjecture

"The Sensitivity Conjecture has stood as one of the most important, and baffling, open problems in theoretical computer science for nearly three decades. It appears to have finally met its match through work by Hao Huang, an assistant professor of mathematics at Emory University. 'I've been attacking this problem off and on since 2012,' Huang says, 'but the key idea emerged for me just about a week ago. I finally identified the right tool to solve it.' Huang posted the proof on his home page and it soon generated buzz among mathematicians and computer scientists on social media, who have praised its remarkable conciseness and simplicity. The Sensitivity Conjecture relates to Boolean data, which maps information into a true-false, or 1-0 binary. Boolean functions play an important role..."

Res-Net Microwave: Precision RF & Microwave Components

Res-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. The company is a leader in development and production of the films required for these type of RF/microwave components. Please check out Res-Net Microwave's website to see how they can help with your current project.

Thursday 13

Radio Month: John T. Frye, Giant Picture Tube TV Sets

Unlike many awards that are presented more for the publicity sake of the presenting entity than for the benefit of the recipient, when the Indiana Radio Council named John T. Frye the state's outstanding amateur radio operator of the year, it was because he truly deserved it. He performed communications operation during weather-related emergency scenarios. For many years, Mr. Frye would further indirectly promote Indiana through his technodrama "Carl & Jerry" and "Mac's Radio Service Shop" series of stories published in Radio & Television News and Popular Electronics magazines. Also mentioned in this instance of "The Radio Month" column in Radio-Electronics magazine is how TV sets owned by students attending the Valparaiso Technical Institute...

Engineer Built Her Own Cellphone with a Rotary Dial

Now this is my kind of cellphone! On her website, Maker Justine Haupt give the motivation for all the work: "Why a rotary cellphone? Because in a finicky, annoying, touchscreen world of hyperconnected people using phones they have no control over or understanding of, I wanted something that would be entirely mine, personal, and absolutely tactile, while also giving me an excuse for not texting." It uses an Arduino controller and a custom-designed slick-looking 3D-printed enclosure. "The point isn't to be anachronistic. It's to show that it's possible to have a perfectly usable phone that goes as far from having a touchscreen as I can imagine, and which in some ways may actually be more functional." It brings a tear to my eye ;-)

High-Precision GNSS Augmentation Service for Europe and USA

"Sapcorda Services GmbH, a GNSS service provider focusing on the emerging high-precision GNSS mass markets, has released its SAPA (Safe And Precise Augmentation) Premium GNSS positioning service. The SAPA service enables mass-market GNSS devices to operate with increased accuracy and reliability across Europe and the continental U.S. The service's technology unlocks advanced performance with instantaneous sub-decimeter position accuracy for devices used in all market applications. SAPA is delivered using the open industry-recognized SPARTN (Safe Position Augmentation for Real-Time Navigation) format, which allows efficient delivery..."

A Portable Thyratron Tester

The thyratron is not necessarily a familiar type of vacuum tube to most RF and microwave electronics practitioners unless they happen to be involved in radar, imaging (x-ray), particle accelerators, etc.† It is basically a high speed, high current switch used in pulse forming networks for firing magnetrons (via a high-voltage transformer). Both the S-band airport surveillance radar and the X-band precision approach radar I worked on in the USAF employed thyratrons. The X-band radar had been modified by the time I came on the scene to use a solid state thyratron (one of the earliest adaptations), but the S-band radar still used its original vacuum tube thyratron. While I don't recall for certain, I believe the thyratron in the thumbnail image is the one it used. The accompanying ruler...

Elusive Terahertz Gap Unlocked with Graphene Amplifier

"Researchers at the Loughborough University have created a unique device which will unlock the elusive terahertz wavelengths and make revolutionary new technologies possible. Terahertz waves (THz) sit between microwaves and infrared in the light frequency spectrum, but due to their low-energy scientists have been unable to harness their potential. The conundrum is known in scientific circles as the terahertz gap. Being able to detect and amplify THz waves (T-rays) would open up a new era of medical, communications, satellite, cosmological and other technologies. One of the biggest applications would be as a safe, non-destructive alternative to X-rays. However, until now, the wavelengths..."

Promote Your Company on RF Cafe for as Little as $45/mo.

RF 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 8,000 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. Advertising begins at $45/month.

Axiom Test Equipment: Rent, Buy, Trade & Repair

Axiom Test Equipment allows you to rent or buy test equipment, repair test equipment, or sell or trade test equipment. They are committed to providing superior customer service and high quality electronic test equipment. Axiom offers customers several practical, efficient, and cost effective solutions for their projects' TE needs and is committed to providing superior customer service and high quality electronic test equipment. For anyone seeking a way to offload surplus or obsolete equipment, they offer a trade-in program or they will buy the equipment from you. Some vintage items are available fully calibrated. Please check out Axiom Test Equipment today!

Wednesday 12

Bargains by the Bagful

This Popular Electronics article by at-the-time editor Oliver Ferrell offers recommendations on how to spot a good deal in grab-bag assortments of electronics components when shopping for good deals, whether it be at a retail outlet, flea market, or Hamfest. The advice is a useful today as it was then. Little did anyone know that half a century later there would be another source for cheap parts that would dwarf what had previously been available - the Internet, and in particular, eBay. Mr. Ferrell mentions the term "radio row," which was a downtown area in many cities where surplus equipment dealers peddled their wares. In the 1950's and 60's, a lot of it was left over from wars, and included not just electronics parts but also mechanical gear. Two of the more famous "radio row" areas were in New York City and Tokyo, which were covered in two other articles titled "Radio a la Cortlandt Street!," and "Akihabara Tokyo's 'Radio Row'," respectively...

Please Thank RF & Connector Technology for Their Support

Providing full solution service is our motto, not just selling goods. RF & Connector Technology has persistently pursued a management policy stressing quality assurance system and technological advancement. From your very first contact, you will be supported by competent RF specialists; all of them have several years of field experience in this industry allowing them to suggest a fundamental solution and troubleshooting approach. Coaxial RF connectors, cable assemblies, antennas, terminations, attenuators, couplers, dividers, and more. Practically, we put priority on process inspection at each step of workflow as well as during final inspection in order to actualize "Zero Defects."

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

RF 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 (of course a gratuity will be graciously accepted). 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...

Problems in Metropolitan TV Reception

Multipath signal interference is as prevalent today as it was at the beginning of radio communications - maybe more so since there are typically more reflective obstacles between the transmitter and the receiver. The evidence of multipath with digital communications, be it voice, Internet page viewing, or movies, is slowness in transmission as opposed to the analog case where garbled speech on radio and ghosting pictures on television are the evidence. High data rates with digital transmissions typically mask the packet errors and their necessary re-transmission; it all happens before the buffered information is presented to the listener / viewer. However, there is no such buffering of over-the-air radio or TV transmissions so evidence of multipath is immediately noticeable. I remember how sometimes...

Webinar: Introduction to Load Pull

Copper Mountain Technologies and Maury Microwave will present a free webinar titled "Introduction to Load Pull," on February 20, from 1:00-2:00 pm EST. "This seminar will cover the A-Z of load pull, starting from basic concepts and techniques and ending in real-life examples of common applications. Participants will learn the reasons why we perform load pull, the various load pull methodologies and their advantages and disadvantages, a dive into the applications of PA design, model extraction and model validation using load pull, and finally examples of applying vector-receiver load pull using Copper Mountain Technologies' Cobalt-series VNAs to these applications..."

Laughing Gas for THz Waves, Peeling Tape for X-Rays

"MIT/Harvard researchers developed a tunable THz-range source using a laser and nitrous oxide, while a team in Mexico characterized the minute X-ray emissions due to triboluminescence when pulling adhesive tape. It's always been a challenge to generate 'THz') waves, the span of electromagnetic spectrum between millimeter and optical wavelengths and generally defined as wavelengths from 1 to 0.1 mm or 300 to 3,000 GHz. While there are vacuum-tube and solid-state devices and assemblies that can do so, these bring many challenges and limitations. Now, a team at MIT in close collaboration with one at nearby Harvard University has developed a laser-pumped, gas-based THz source that can be fine-tuned over 37 lines spanning..."

Centric RF: Attenuators, Adapters, Cable Assemblies, Power Dividers

Centric RF is a company offering from stock various RF and Microwave coaxial components, including attenuators, adapters, cable assemblies, terminations, power dividers, and more. We believe in offering high performance parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz at power levels from 0.5-500 watts are available off the shelf. Order today, ship today! Centric RF is currently looking for vendors to partner with them. Please visit Centric RF today. 

Tuesday 11

Micro-Modules

"Micro" as applied to electronics is relative, depending on which decade you reference. In the 1940s, a micro-size electronic assembly might have included "peanut" vacuum tubes and even some sort of printed circuit board. That was a huge step down in size from standard size tubes with point-to-point wiring between tube sockets and solder lugs on switches, potentiometers, variable capacitors, etc. Fixed value leaded resistors, capacitors, and inductors, and transformer wires connected to those lugs as well as to many terminal strips installed specifically for making connections. Once transistors came on the scene in the 1950s, a new round of miniaturization took place based on not just a significantly smaller size of solid state transistors and diodes, but their lower voltage and current requirements meant ancillary components could be made smaller as well due to lower voltage...

Please Welcome Lemos International Technologies as a New Advertiser!

Lemos International Technologies is both a designer and manufacturer of wireless products and a distributor of products from other world-class manufacturers. A modular approach to wireless connectivity helps eliminate much of the technical design and testing and also simplifies or eliminates the need for expensive conformance testing and certification. Ready-to-use Bluetooth, GPS, Wi-Fi, licensed and unlicensed band products are available. Custom design services can help you achieve success with your project's unique needs.

Father of Radar Gets His Reward from Patent Office

Well, this might get some dander up amongst the believers that Sir Robert Watson-Watt is "the Father of Radar." In the December 1957 edition of Popular Electronics magazine, Colonel William R. Blair was given that honored designation based on his work on a pulse-echo method of direction finding in the 1920s. The Wikipedia entry for Col. Blair refers to him more specifically as the "Father of American Radar." William R. Blair was awarded U.S. patent #2,803,819, titled "Object Locating System," on August 20, 1957 - a full 13 years after the patent application was submitted. Watson-Watt was issued a patent in 1935 on a radio device for detecting and locating an aircraft. His research was born out of an investigation into a "death ray" which had reportedly been invented by the Germans.

Smart Visor Tracks the Sun While You Drive

This is a great idea - and long overdue! "The liquid crystal display blocks the sun in just the right spots. The automotive sun visor has been around for nearly a century, first affixed in 1924 as a 'glare shield' on the outside of a Ford Model T. Yet despite modest advances -lighted vanity mirrors, anyone? - it's still a crude, view-blocking slab that's often as annoying as it is effective. Bosch, finally, has a better idea: An AI-enhanced LCD screen that links with a driver-monitoring camera to keep the sun out of your eyes without blocking the outward view. The German supplier debuted the Bosch Virtual Visor at the recent CES show in Las Vegas. The Virtual Visor project began when Ryan Todd, a Bosch engineer in suburban Detroit, started daydreaming about what TV he wanted to buy during his sun-stroked commute..."

RF Cascade Workbook 2018

RF Cascade Workbook 2018 is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. 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...

5G in Manufacturing: What's Here and What's to Come

Unlike pervious enumerated "Gs," 5G is much more than cellphone connectivity. 5G encompasses all forms and uses of super wide bandwidth and upper GHz and even THz band operational frequencies. Cellphones represent only a part of that paradigm. As stated in this article from the February 2020 issue of NASA Tech Briefs magazine, "For the first time, 5G offers a data rate and reliability comparable to wired communication." Factory automation and "smart" networks comprise a huge part of the 5G master plan. As such, security is a major concern, since breaches dataflow can result in not just pilfered information, but the scuttling of critical processes which could destroy manufacturing and associated profits. Worst case scenarios include disruption of critical utility systems and even situations harmful to the human population through contamination. This "5G in Manufacturing: What's Here and What's to Come" article is definitely a good read.

MECA Electronics: Passive RF & Microwave Components

Since 1961, MECA Electronics has designed and manufactured an extensive line of RF & microwave components for in-building, satellite, radar, radio, telemetry, mobile radio, aviation & ATC. Attenuators, directional & hybrid couplers, isolators & circulators, power dividers & combiners, loads, DC blocks, bias-Ts and adapters & cables. MECA has long been the 'backbone' of high performance wired and air-interfaced networks such as in-building applications, satellite communications, radar, radio communications, telemetry applications, mobile radio, aviation & air traffic communications.

Monday 10

QuinStar Cryogenic Line Featured at American Physical Society Meeting

"QuinStar-Cryogenic-Line-American-Physical-Society-Meeting-2-5-2020.htm" target="_top"> QuinStar Technology will feature its cryogenic product line at the American Physical Society March Meeting. This event is March 2nd through 4th at the Colorado Convention Center in Denver. QuinStar "QuinStar-Cryogenic-Line-American-Physical-Society-Meeting-2-5-2020.htm" target="_top"> cryogenic circulators, isolators, and arrays offer exceptional broadband performance down to the mK range. These components support applications such as quantum computing, radio astronomy, STM research, particle physics research, and electron spin resonance measurement systems. QuinStar engineers have over 36 years of experience in cryogenic ferrite design. With this extensive experience, we continually advance state-of-the-art...

The Japanese Morse Telegraph Code

Less than a year had passed since the surprise attack on Pearl Harbor by the Japanese navy when this article was published in QST. America had sprung into high gear to help the war effort - both as civilians and as military members. A vital part of the strategy was to educate as many people as possible regarding the tactics and habits of the enemy. Media of all sorts were used to help get the word out. QST did its part, probably more so than most forms of media, by appealing to those people capable and willing to contribute to the vitally important task of communications. How many hobbies could be directly applied to the needs of the military and homeland defense? Precious few, other than radio design, assembling, testing, and operation. I suppose to be fair I would have to mention a few other hobbies like vehicular maintenance, firearms marksmanship, and model building...

Thanks to Transient Specialists for Continued Support!

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

Gilbert U-238 Atomic Energy Lab

This is amazing, especially considering what good condition it is in. "The Gilbert U-238 Atomic Energy Lab let kids measure radioactivity and prospect for radioactive ores," so says the article on the IEEE Spectrum magazine website. Along with a detailed description of the kit is a video explaining the contents. "When the Atomic Energy Lab hit the market in 1950, it was one of the most elaborate science kits available. In addition to uranium, it had beta-alpha, beta, and gamma radiation sources. It contained a cloud chamber, a spinthariscope, an electroscope, and a Geiger counter, as well as a 60-page instruction book." Author Allison Marsh asks the legitimate question of whether today's overly protective child safety laws have prevented science learning "toys" like this one from being made available. As a kid, I had Gilbert chemistry sets that probably cannot be sold today. BTW, you can buy uranium ore on Amazon but your plutonium samples must be procured from Libyan terrorists.

Best Thermal Testing Practices on Electronic Devices

"TotalTemp-Technologies-Best-Thermal-Testing-Practices-Electronic-Device-2-3-2020.htm" target="_top"> TotalTemp Technologies has another good blog article posted entitled, "Best Thermal Testing Practices on an Electronic Device." There are many reasons thermal testing on products is required. Primarily to verify that the product will work properly in the environment (thermal and otherwise) that it is intended to perform. Sometimes, also to discover end-of-life issues for products, maximize performance or to weed out early failures that might result in product failures For reasons primarily of simplicity and ease of use, the most widely employed method of forcing products to temperatures for thermal testing is a (convection based) temperature chamber. According to laws of Thermodynamics, heat transfer (in and out of a product) is accomplished through one or more of the three following methods. Conduction, convection and radiation...

ConductRF: Precision & Standard Grade RF Cable Assemblies

ConductRF 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! 

Sunday 9

Engineering & Science Crossword Puzzle for February 9

As with my hundreds of previous science and engineering-themed crossword puzzles, this one for February 9, 2020, contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc., which I have built up over nearly two decades. Many new words and company names have been added that had not even been created when I started in the year 2002. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure village in the Andes mountains. You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which, if you don't already know, might surprise you.

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.

Homepage Archive Pages

2026:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2025:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

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)

- Christmas-themed items