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Today in Science History

Electronics & Tech  Headlines

Tech Industry Headlines - RF Cafe - Archive -

• Foxconn's January Sales Surge to $22B after Wuhan Flu Disruption

• How Rural Broadband Impact Telecom Workforce

• NAB to Host Recruitment Webinar

• 5 Ways Manufacturers Prepare for Recession

• Tougher China Dual-Use Sanctions, Lax Enforcement

• Chinese Spy Balloon Flying over U.S. (shoot it down!)

• 5G Americas Explores the Adoption of 5G

• Bleak Picture for Global Smartphone Market

• Yaesu Radios Donated to ARRL to Inspire Visitors and Young Hams

How's Your Math?

How's Your Math?, December 1942 QST - RF CafeIf you are just starting out in the realm of electronics or maybe just need a little freshening up of your basic math skills, this rather extensive article from a 1942 issue of QST magazine is just what you need. Author Dawkins Espy does a really nice job of laying out the basics of algebraic operations, Ohm's law, trigonometry, and logarithms. Examples are provided for each category. In this day of calculators doing all the hard work of calculating logs, antilogs, and trig functions, it does even seasoned veterans at electronics calculations a bit of good to do a quick read-through to knock off cobwebs in the gray matter. How long has it been since you have seen tables of sine, cosine, and tangent values and/or tables of logarithms? Not long enough, you say?

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

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 to Wireless Telecom Group for Their Support!

Wireless Telecom Group (RF power and noise measurement) - RF CafeThe Wireless Telecom Group, comprised of Boonton, Holzworth, and Noisecom, is a global designer and manufacturer of advanced RF and microwave components, modules, systems, and instruments. Serving the wireless, telecommunication, satellite, military, aerospace, semiconductor and medical industries, Wireless Telecom Group products enable innovation across a wide range of traditional and emerging wireless technologies. A unique set of high-performance products including peak power meters, signal generators, phase noise analyzers, signal processing modules, 5G and LTE PHY/stack software, noise sources, and programmable noise generators.

Chinese Spy Balloon Finally Shot Down

Chinese Spy Balloon Shot Down - RF CafeAs of September 16, 2022, if I fly my radio-controlled model airplane, helicopter, or drone even an inch off the ground anywhere in the U.S. without having a specially designed and certified electronics device - at my expense - broadcasting identification and position data ("Remote ID of Unmanned Aircraft"), I can be fined and/or jailed and/or have my equipment confiscated by the U.S. government. The stated justification is concern for safety of property, persons, and national security. However, if a country established as a military and economic threat to the U.S. flies a huge uncontrolled (other than by altitude in air currents) aircraft burdened by maybe 1000 pounds of equipment, including batteries, from coast to coast across populated areas, no action is taken. Here is a video of the Chinese balloon finally being shot down over the ocean after it was allowed to collect and relay data, and even possibly release pathogens over wide areas for days (NOAA HYSPLIT trajectory). Here's Trump impersonator Shawn F. with his take on the Chinese spy balloon debacle. Another victory for China!

Electronics Theme Crossword for February 5

Electronics Theme Crossword Puzzle for February 5, 2023 - RF CafeThis custom RF Cafe electronics-themed crossword puzzle for February 5th contains words and clues which pertain strictly to the subjects of electronics, mechanics, power distribution, engineering, science, physics, astronomy, chemistry, etc. If you do see names of people or places, they are directly related to the aforementioned areas of study. As always, you will find no references to numbnut movie stars or fashion designers. Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds of them dating back to the year 2000. Enjoy.

Get Your Custom-Designed RF Cafe Gear!

Custom-Designed RF-Themed Cups, T-Shirts, Mouse Pads, Clocks (Cafe Press) - RF CafeThis assortment of custom-designed themes by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins, Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's" design has been ripped off by other people and used on their products, so please be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢ per item - Cafe Press gets the rest of your purchase price. These would make excellent gifts for husbands, wives, kids, significant others, and for handing out at company events or as rewards for excellent service. It's a great way to help support RF Cafe. Thanks...

Many Thanks to KR Electronics for Long-Time Support!

KR ElectronicsKR Electronics has been designing and manufacturing custom filters for military and commercial radio, radar, medical, and communications since 1973. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop, equalizer, duplexer, diplexer, 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.

Carl & Jerry: Going Up, Up, Up

Carl & Jerry: Going Up, Up, Up March 1955 Popular Electronics - RF CafeThanks to Mr. Ferrous Steinka for submitting this commentary on the episode of Carl & Jerry appearing in the March 1955 issue of Popular Electronics. "Radio and television waves are reflected in the same way as light waves. As both light and radio waves are forms of electromagnetic waves, they are both subject to the same basic laws and principles. Visual examples of light reflection are everywhere from specific mirrors to flat reflective surfaces like glass, polished metal and the like. So too, radio waves can experience reflection. Conducting media provide the optimum surfaces for reflecting radio waves. Metal surfaces, and other conducting areas provide the best reflections, so the story below is feasible and within the known technology at the time. The use of a highly directional Yagi antenna would have been very important because without it the reflected waves would have been inverted (out of phase) with the normal signals, thereby reducing the overall received signal..."

Antennas & Microchips Blur Line Between Science and Sci-Fi

Antennas and Microchips Blur Line Between Science and Sci-Fi - RF Cafe"Sophisticated antenna arrays paired with high-frequency wireless chips act like superpowers for modern electronics, boosting everything from sensing to security to data processing. In his lab at Princeton, Kaushik Sengupta is working to expand those powers even further. In recent years, Sengupta's lab has designed antenna arrays that help engineers make strides toward peering through matter, boosting communications in canyons of skyscrapers, putting a medical lab on a smart phone, and encrypting critical data with electromagnetic waves instead of software. In a new article in Advanced Science, Sengupta's research team presented a new type of antenna array based on the paper-folding art of origami. The shape-shifting array, designed like a folded paper box called a waterbomb..."

Voices in the Mail

Voices in the Mail, August 1956 Popular Electronics - RF CafeThis 1956 Popular Electronics magazine article reports on the very earliest form of voice mail - recording a message on a reel-to-reel tape deck, placing it in an envelope, and snail mailing it to its recipient. Sure, it was slow, but unless you were under surveillance for some suspected crime, there was just about zero chance that some government agency was going to hear your private message. I had forgotten about it until reading this, but I remember that back in the 1960s, my father bought an el cheapo tape deck for our family and one for his parents, who lived in Buffalo, New York. My parents and four sisters and I had a pretty good time hamming it up on the tape, and looked forward to receiving a reply tape a month or two later. "Grandpa B," as we kids called him, was a real funny guy and kept us entertained for about 30 minutes with the reply tape. The exchange lasted for about a year and then our machine died (I probably broke it by opening the case and screwing with it) and then it was back to the long distance phone calls once or twice a year...

Anatech Electronics Intros 3 Filter Models

Anatech Electronics Intros 3 Filter Models for Early February 2023 - RF CafeAnatech 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. Three new filter surface mount, low loss ceramic bandpass filter models have been introduced - a 2410 MHz WiFi cavity bandpass filter with a 3 dB bandwidth of 22 MHz, a 4885 MHz cavity bandpass filter with a 50 MHz bandwidth, and a 5630 MHz WiFi cavity filter with a bandwidth of 20 MHz. Custom RF power filter and directional couplers designs can be designed and produced with required connector types when a standard cannot be found, or the requirements are such that a custom approach is necessary...

1953 Radio Shack Advertisement

Radio Shack Advertisement, November 1953 QST - RF CafeAgainst all odds, Radio Shack is still in operation today (barely). They still sell a fairly broad selection of discrete components for circuit designers and for repair and modifications. Radio Shack is and has been for a couple decades the only hometown source for parts where you can walk in off the street to get what you need, rather than order it online. Even items like a dual-gang stereo volume control potentiometer, a 2-layer, 6-position rotary switch, and a DPDT PCB-mountable relay can be had. There are nowhere near as many as there were a few years ago before all the turmoil began, but Radio Shack is still there in a pinch. This full-page Radio Shack advertisement appeared in the November 1953 edition of QST magazine, which was during the heyday of electronics DIY activity. I've written in the past of visiting the local Annapolis, Maryland, Radio Shack store with a bagful of vacuum tubes from our television set needing testing on their testing machine. There was also a Lafayette Radio Electronics store...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook 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 (click here for screen capture). 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 ISOTEC for Continued Support!

ISOTEC Corporation - RF CafeSince 1996, ISOTEC has designed, developed and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components and filters for wireless service providers including non-magnetic connectors for quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM RF connectors components such as power dividers and directional couplers. Off-the-shelf and customized products up to 40 GHz and our low-PIM products can meet -160 dBc with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and high-performance. Designs that are cost effective practical and repeatable.

Introduction to Ultrasonics

Introduction to Ultrasonics, August 1960 Radio-Electronics - RF CafeThis "Introduction to Ultrasonics" article from a 1960 issue of Radio−Electronics magazine does not necessarily directly apply to RF and microwaves, but there are similarities in the circuitry and theory of generation and propagation. I was surprised to learn that ultrasonics even back then went into the low GHz realm. Any mechanical vibrations about about 20 kHz are regarded as ultrasonic. Ultrasonics can preform some of the functions of x-rays in material inspection, without the danger of ionizing radiation and extremely high voltages required to generate the rays. While working in the 1980's as an electronics technician at the Westinghouse Oceanic Division in Annapolis, Maryland, I often used an ultrasonic cleaner like the one shown here for removing flux from printed circuit board assemblies (PCA's), cable connectors, and other objects. The heated methyl-based bath solution produced a PCA with shiny solder joint totally devoid of flux residue. We were still using 60/40, Sn/Pb rosin core solder back then. We built sonar systems and components for the U.S. Navy, including transducer-equipped torpedo nose cones, sonar transducer arrays for ship hulls, and towed sonar systems...

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.

THz Quantum Magnetic Switch at RT

Room Temperature THz Quantum Magnetic Switch - RF Cafe"A class of nonvolatile memory devices, called MRAM, based on quantum magnetic materials, can offer a thousandfold performance beyond current state-of-the-art memory devices. The materials known as antiferromagnets were previously demonstrated to store stable memory states, but were difficult to read from. This new study, now published in Nature, paves an efficient way for reading the memory states, with the potential to do so incredibly quickly too. You can probably blink about four times a second. You could say this frequency of blinking is 4 hertz (cycles per second). Imagine trying to blink 1 billion times a second, or at 1 gigahertz, it would be physically impossible for a human. But this is the current order of magnitude in which contemporary high-end digital devices, such as magnetic memory, switch their states as operations are performed. And many people wish to push the boundary a thousand times further, into the regime of a trillion times a second, or terahertz. The barrier for realizing faster memory devices may be the materials used..."

Now! Use Gift Cards for Payment!

Send Gift Cards to RF CafeSince Elon Musk purchased Twitter and began exposing the grotesque level of bias and suppression of free speech perpetrated by social medial platforms, some people have written to say they no longer want to use PayPal when purchasing RF Cafe products. I have been agreeing to send the software immediately with a promise of payment via snail mail. On a whim, I checked to see whether Gift Cards can be sent via e-mail, and indeed they can. So, if you want an alternative to PayPal, I have posted links directly to Walmart, Lowe's, Home Depot, and Sam's Club, where the majority of my purchases are made. Of course you are also encouraged to send donations via Gift Cards. Thank you.

Radar on the Great Lakes

Radar on the Great Lakes, February 1947 Radio News - RF CafeAn article title with both "radar" and "Great Lakes" (I lived a mile from Lake Erie) in the title is sure to catch my attention, as did this. Author Norman Schorr reports on the state of the art of radar equipment and usage for the purpose of maritime navigation. Research and development, along with an ample surplus of components left over from World War II facilitated a rapid adaptation of radar to many venues. Included among its applications were airway and waterway navigation, rocket trajectory tracking, security systems, speed measurement, weather observation, and aerial mapping. It is easy to take for granted the capabilities of radar today with having the accumulated knowledge of more than half a century on our side, but pioneers in the field had to think everything up anew. I have to admit to being familiar with what a "Pliotron" was prior to reading this article (it is Irving Langmuir's high frequency version of the Audion vacuum tube)...

Horizontal Hamming

Horizontal Hamming, May 1951 QST - RF CafeHere is a humorous story from a 1951 issue of QST magazine - probably not too far from being true - about a Ham operator (emphasis on "operator") who parlayed a short spat of poor health into an opportunity to get in a little rag-chewing time. The whole scenario turned out so well that he pondered afterward whether he could indulge in a bit of malingering for a repeat opportunity. So did some of the contacts he told about it while laid up. The tale didn't appear in an April edition, so it probably is on the up-and-up...

Bendix Aviation Corporation

Bendix Aviation Corporation, March 23, 1942 Life - RF CafeBendix Corporation was begun in 1914 by Mr. Vincent Bendix, eventually manufacturing brakes, starters, carburetors, and other components for automobiles, trains, and airplanes. During World War II, Bendix was a major supplier of critical components, including radio transmitters and receivers and avionic instruments. As with many - probably most - big corporations, advertisements were run in many magazines in order to make sure the public knew the part their companies were playing in the effort to defeat Communism, Nazism, Socialism, and all the other "isms" worldwide seeking to subdue and destroy freedom. Bendix branched out into many areas of development and production with computers, mine detectors, inertial guidance platforms (for Saturn V and other man-carrying rockets), televisions, phonographs, kitchen appliances, and much more. I don't know if it is still the case, but back in the 1970's when I did a lot of work on my 1969 Camaro SS, the term "bendix" was a generic reference to the solenoid-actuated spur gear that coupled the electric starter to the big starter gear connected to the engine crankshaft...

Adson Radio & Electronics Co. Advertisement

Adson Radio & Electronics Co. Advertisement, January 1949 Radio & Television News - RF CafeHere's another advertisement that you probably wouldn't see in a contemporary RF / microwave engineering magazine, like this one in the 1949 issue of Radio & Television News. For that matter you probably wouldn't see it on a contemporary RF / microwave engineering website ... except on RF Cafe where political correctness finds no sanctuary. Adson Radio & Electronics, an electronic components distributor, was located on Fulton Street in New York City, just a block from the 911 Memorial. The original building might well have been destroyed when "some people did something" (Saudi Arabians flew two commercial jetliners into the World Trade Center towers) in 2001...

Please see the RF Cafe Homepage Archives for previous items of interest...

Exodus Advanced Communications Best in Class RF Amplifier SSPAs - RF Cafe
Triad RF Systems Amplifiers - RF Cafe
RF Cascade Workbook 2018 by RF Cafe
Windfreak Technologies Frequency Synthesizers - RF Cafe
Axiom Test Equipment - RF Cafe

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About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024


    Kirt Blattenberger,


RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

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