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Homepage Archive - December 2023 (page 4)

See Page 1 | 2 | 3 | 4 | of the December 2023 homepage archives.

Final Electronics-Theme Crossword for 2023!

Electronics Theme Crossword Puzzle for December 31st, 2023 - RF CafeThis is the RF Cafe electronics theme crossword puzzle is for December 31st. Hard to believe it is the final crossword for 2023! This being the 31st day of the month, many of the words begin and/or end with the letter "E." Since there are only 26 letters in the alphabet, I use the modulo function to derive the letter to use; i.e., 31 mod 26 = 5. Clues for words containing "E" are marked with an asterisk (*). Related clues are marked with an asterisk (*). All RF Cafe crossword puzzles are custom made by me, Kirt Blattenberger, and have only words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects. 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., Reginald Denny, Hedy Lamarr, or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. 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, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We Are the World's Matchmakers" Smith chart design. These would make excellent gifts for husbands, wives, kids, significant others, and for handing out at company events or as rewards for excellent service. My graphic has been ripped off by other people and used on their products, so please be sure to purchase only official RF Cafe gear. I only make a couple bucks on each sale - the rest goes to Cafe Press. It's a great way to help support RF Cafe. Thanks...

Friday the 29th

War Advertising Council

War Advertising Council, February 1944 Popular Science - RF CafeI'm probably one of the few people remaining who fairly regularly recite the World War II (WWII) era slogan of "Use it up. Wear it out. Make it do, or Do without." One of the primary killers of economies has been inflation, whatever the cause - usually deficit spending by government and/or printing of fiat money. Wartime typically produces high inflation levels due to the need to produce the equipment necessary to wage a battle. Supply and demand are another cause of inflation. If the demand is greater than the supply, prices go up because owners want to maximize profits. If the need for skilled labor is greater than what is available, workers demand higher pay, and the price goes up. During WWII, as the chart to the upper left shows, inflation rates were sky high, and the government propagandists called on the citizens to "do their part" to keep prices under control by not creating a higher demand then the supply chain could accommodate...

Radio Dumping

Radio Dumping, February 1939 Radio-Craft - RF Cafe"The situation is one that is difficult, if not wholly impossible to eradicate, because of all modern, 20th Century machine age products, the radio receiver of today undergoes more violent and more radical changes than almost any other single item we can think of." That was the lament of electronics inventor, publisher, and industry visionary Hugo Gernsback in 1939! He wrote in the February issue of Radio−Craft magazine of the practice of electronics component manufacturers vastly overproducing products and then, when they are quickly obsoleted due to newer better ones entering the market space, selling at below cost in hopes of recovering at least some of their investment. For a man who otherwise encouraged, welcomed, and participated in the pushing forward of technological frontiers, the attitude seem strangely at odds with his raison d'être. "This 'dog eat dog' process has gone on ever since and will probably go on for a long time to come." He had no idea ... or maybe he did...

Superatomic Semiconductor Sets Speed Record

Superatomic Semiconductor Sets Speed Record - RF Cafe"Semiconductors, particularly silicon, are fundamental to the operation of various electronic devices such as computers, cellphones, and the device you're currently using. Despite their widespread use, semiconductors have inherent constraints. The atomic structure of these materials is subject to vibrations, resulting in the generation of quantum particles known as phonons. These phonons lead to scattering of the particles - either electrons or electron-hole pairs termed excitons - responsible for transporting energy and information in electronic devices. The scattering occurs over extremely small distances (nanometers) and brief time spans (femtoseconds), causing energy dissipation as heat and imposing a limit on the speed of information transfer. The search is on for better options. Writing in Science, a team of chemists at Columbia University led by Jack Tulyag, a PhD student working with chemistry professor Milan Delor, describes the fastest and most efficient semiconductor yet: a superatomic material called Re6Se8Cl2..."

The Radio Month in Review

The Radio Month in Review, April 1936 Radio-Craft - RF CafeDid you know that some radio service equipment can be financed by the Federal Housing Administration (FHA)? That's right, if your business needs a new tube tester or maybe an oscilloscope, Uncle Sam is there to help. That was in 1936, anyway, per this Radio-Craft magazine news blurb. Today, of course, the FHA no longer makes loans for business equipment - the Small Business Administration (SBA) takes care of that. Nowadays the FHA restricts itself to home loans - including to illegal residents, those with no money for a down payment, and otherwise traditionally unqualified. Also reported, among lots of other interesting stuff, is some early instances of RFI (radio frequency interference) emanating from hospital equipment. Oh, and an anecdote regarding a Babe Ruth run-in with the coppers. Note the Thompson submachine gun (aka Tommy gun) pointed at him in the drawing.

RF & Electronics Symbols for Office™

RF & Electronics Schematic & Block Diagram Symbols for Office™ r2 - RF CafeIt was a lot of work, but I finally finished a version of the "RF & Electronics Schematic & Block Diagram Symbols"" that works well with Microsoft Office™ programs Word™, Excel™, and Power Point™. This is an equivalent of the extensive set of amplifier, mixer, filter, switch, connector, waveguide, digital, analog, antenna, and other commonly used symbols for system block diagrams and schematics created for Visio™. Each of the 1,000 or so symbols was exported individually from Visio in the EMF file format, then imported into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or down without becoming pixelated, so all the shapes can be resized in a document and still look good. The imported symbols can also be UnGrouped into their original constituent parts for editing. Check them out!

Thursday the 28th

Forecaster Dials Weather from Known Conditions

Home Forecaster Dials Weather from Known Conditions, April 1943 Popular Mechanics - RF Cafe"Home Forecaster Dials Weather from Known Conditions" is the title of this news blurb from a 1943 issue of Popular Mechanics magazine. Back when I was a kid in the 1960s and 1970s, dialing the weather meant inserting my index finger into the holes on the rotary phone and dialing WE6-1212 (the time was gotten by dialing TI6-1212), and then listening to the recorded current conditions and forecast for the next 24 hours. I called often (my father referred to the recording lady as my girlfriend) due to both a keen interest in weather phenomena and wanting to know whether the conditions would be good for flying a model airplane or launching a model rocket. This cardboard dial calculator required the user to input current observed conditions for wind direction, barometric pressure and whether it was rising or falling, and your opinion on whether the weather (see what I did there?) was "fair," "overcast" or "raining." I assume "snow" could be substituted for "rain" if appropriate. The device would then provide a forecast for the next 12-24 hours, within a radius of about 30-50 miles. When taking private pilot lessons in the late 1970s, I was taught to estimate conditions in somewhat the same manner, except cloud type is a good visual indicator of things to come. Winds aloft, distant high and low pressure systems...

Eliminating Rare Earth Metals in EVs

Wound-Rotor Synchronous Motor - RF CafeElectronic Design magazine has been running a series of articles highlighting new motor technology that eliminates the need for rare earth element permanent magnets, thus removing China and other hostile nations from the supply chain. Known as wound-rotor synchronous motors (WRSM), they replace the now-standard permanent-magnet synchronous motors (PMSM) by substituting permanent magnets with electromagnets. Doing so requires a battery to generate the magnetic field to get the motor started and to sustain operation, thus reducing its overall efficiency, but not by so much as to make it undesirable. Some versions of the WRSM use slip rings for conducting current to the field windings, but designs are appearing which use induction to eliminate physical (and thus wearing) contact. I personally hope this technology mature quickly. More essential, though, is to find a replacement for lithium battery cells that does not require such massive mining operations that destroy the environment around them and harbor unsafe working conditions that would not be tolerated by OSHA in this country. Here are Part 1, Part 2, and Part 3.

The Radio Manufacturer Has His Say

The Radio Manufacturer Has His Say, May 1930 Radio-Craft - RF CafeUnlike the last two decades where people like me have been making it available, procuring service information on commercial products could be very time consuming, and often resulted in not even obtaining what was needed. Thanks to the Internet now being populated with schematics and mechanical drawings for seemingly everything ever made, we no longer need to call or mail order for information needed to repair your radio, television, cellphone, lawn mower, toaster, or anything else. Granted, most people these days toss out broken items and just buy new ones. Before the advent of companies like Sam's Technical Publishing information packets, it was often impossible to obtain schematics and service information from manufacturers unless you were a certified service shop and/or dealership. In response to many inquiries from Radio-Craft magazine's readers, publisher Hugo Gernsback queried the top manufacturers of the day to determine their policies for distributing such data...

Metasurface Antenna for High-Security 6G

Metasurface Antenna for High-Security 6G - RF Cafe"A research team led by Professor Chan Chi-hou, Chair Professor of Electronic Engineering at City University of Hong Kong, achieved an unprecedented advance in antenna technology by making possible the manipulation of all five fundamental properties of electromagnetic waves through software control. In a world first, the team developed a universal metasurface antenna that allows the independent and simultaneous manipulation of amplitude, phase, frequency, polarization and direction of electromagnetic radiation. 'A universal component capable of manipulating all the fundamental wave properties is the Holy Grail for physicists and engineers,' said Professor Chan, who is also Director of the State Key Laboratory of Terahertz and Millimeter Waves (SKLTMW). As research on 6G wireless communication systems progresses worldwide, the universal metasurface antenna holds immense potential for various applications in 6G systems. Its advanced waveform manipulation capabilities and enhanced security features are crucial for integrating sensing..."

Cartoon Advertising for Radio Service Men

Cartoon Advertising for Radio Service Men, February 1933 Radio-Craft - RF CafeThe Star Radio Company, in Washington, D.C., was lauded in its day for pioneering the use of humor in its print advertising. This 1933 issue of Radio-Craft magazine presents a few examples of their handiwork - some of which would probably never be approved for publication in today's hypersensitive environment. I searched for more info on the company, but all I could find was a Library of Congress photo of a display of automatic washers and ironers - considered as high tech in the day as any vacuum tube radio. My grandmother had one of those wringer washing machines back in the 1960s. The wringer mechanisms were real safety hazards, hence the old quip about there not having been so much excitement around the house since granny got her <3-letter word> caught in the wringer. Anyway, enjoy the cartoon ads as you're waiting for the first weekend in spring...

RF & Electronics Stencils for Visio

RF & Electronics stencils for Visio r4 - RF CafeWith more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1 scale so that measurements can be made directly using Visio built-in dimensioning objects. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...

Wednesday the 27th

1958 Old Farmer's Almanac Puzzles

Old Fashioned Puzzles, 1958 Old Farmer's Almanac - RF CafeIf you like solving puzzles, maybe you'll want to give these from the 1958 issue of The Old Farmer's Almanac (OFA) a try. I through V are pretty straightforward, but VI and VII are a tad strange. Don't overthink VI and VII because they're not brainiac material. I plugged part of the solution into Google and could not find anything that indicates they descend from some great works or prose. I worked them out to demonstrate what I mean. Puzzles I through V do not contain any tricks, just solve them as presented and you'll have no problem. Thought processes were different back in the day, as is evidenced by looking at some of the other OFA puzzles in the list...

Attracting Customers Who Want to Thermal Testing

Attracting Customers Who Want to Perform Thermal Testing - RF CafeMeeting the required thermal testing requirements and performing it in less time is what TotalTemp Technologies offers. When a device is suited to testing on a thermal platform, that will always be our first recommendation. That is to say, the device has a fairly low profile and a flat thermally conductive surface. Fortunately, many electronic modules such as microwave modules and power amplifiers are already optimized for this configuration of test. Applying some thought to the process can make it more efficient. If a little bit of fixturing helps the device have a good thermally conductive surface, that will go a long way to facilitate faster testing. A secondary sensor on the device, especially if it is tall, can tell you when the point you actually care about has reached the required temperature. The optional Synergy Nano advanced temperature control algorithm can assure the fastest ramp to temperature and avoid excessive overshoot, which could damage parts. Keeping in mind how much more effective conductive heat transfer is, sometimes it just doesn't work for the device to be tested. In that case, a temperature chamber remains the best choice, TotalTemp is here to offer temperature chambers with fast, programmable transition rates and sufficient airflow to ensure good heat transfers to and from the device...

Decoding the Invention of the Radio

Decoding the Invention of the Radio - RF CafeHere is an interesting discussion on the TruthOrFiction.com website entitled "Decoding the Invention of the Radio: A Scientific Retrospection." Attempting to discredit and/or defame historical figures for their accomplishments is a form of sport these days. Tearing down monuments, renaming institutions, banning publications, and demanding that people accept and even rejoice in those practices has reached pandemic proportions. I have nothing against legitimate research showing that past assumptions were in error.  Some keep trying to show Einstein's theory of general relativity is wrong, or that Whitehead flew a powered airplane before the Wrights, or that Gray had a working telephone prior to Bell. This article does not attempt to fully discredit Maxwell as the inventor of radio, but points out that many others, including Tesla, Hertz, Popov, and Lodge contributed greatly to the knowledge that facilitated Marconi's success. While a useful story, my guess is that it is "preaching to the choir" instance since most people capable of answering the question of "Who invented the radio," with a reply of James Clerk Maxwell also know of the other men's work. That is probably not as true for the invention of the aeroplane or the telephone...

Short-Cuts in Radio

Short-Cuts in Radio, December 1936, Radio-Craft - RF CafeFirst prize in this circa 1936 reader-submitted design ideas went to William G. Scott for his wind-powered battery recharger. It was a rather elaborate contraption made of surplus lawn mower and automobile (Ford Model T, no less) generators. There are two very good reasons why someone would find the need to build his own battery charger in the era. First, good luck finding a commercial product to do the job, and if you could, the cost would be prohibitive for most radio enthusiasts. Second, prior to the Rural Electrification Act of 1936 (which took many years to fully implement), most households not in or near cities and towns had no commercial electric service. Electricity, if any, was supplied by deep cycle storage batteries for powering radios, electric lights (as opposed to kerosene or gas lights), kitchen appliances, etc. Many farms had windmills that did double duty of pumping ground water and driving a generator. BTW, a $10 prize in 1936 is, according to the BLS' Inflation Calculator, the equivalent of $219 in 2023 money...

How to Target RFCafe.com for Your Google Ads

Google AdSense - it makes good sense - RF CafeOne aspect of advertising on the RF Cafe website I have not covered is using Google AdSense. The reason is that I never took the time to explore how - or even whether it is possible - to target a specific website for displaying your banner ads. A couple display opportunities have always been provided for Google Ads to display, but the vast majority of advertising on RF Cafe is done via private advertisers. That is, companies deal with me directly and I handle inserting their banner ads into the html page code that randomly selects and displays them. My advertising scheme is what the industry refers to as a "Tenancy Campaign," whereby a flat price per month is paid regardless of number of impressions or clicks. It is the simplest format and has seemed to work well for many companies. With nearly 4 million pageviews per year for RFCafe.com, the average impression rate per banner ad is about 280,000 per year (in eight locations on each page, with >17,000 pages). That's pretty good exposure for $300 per month. Some companies have expressed an interest in being able to manage their advertising accounts themselves a la the Google AdSense program...

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. 50 Ω and 75 Ω models are available, along with a full line of precision calibration and connector adaptors.

Tuesday the 26th

Radio Corporation of America

Radio Corporation of America, January 1953 Popular Mechanics - RF CafeThe Radio Corporation of America, more widely known as RCA, contributed as mightily to the science of wired and wireless communications as International Business Machines (IBM) did to analog and digital computing. Inventions created by RCA for specific applications were often repurposed (a word not even in existence - or at least common parlance - in 1953 when this appeared in Popular Mechanics magazine) for other uses. Such was the case for the multiplier phototube - which is nowadays referred to as a photomultiplier tube (PMT). RCA engineers used a PMT designed to be sensitive enough to detect starlight through a telescope, in a circuit that detects the headlights of oncoming cars and switches the host car's headlights off of high beam (if that's where they were set). Many - maybe most - of the Popular Electronics, Mechanix Illustrated, and Popular Science magazines I have from that era feature similar full-page ads by RCA and Bell Telephone Laboratories. They also showed up in magazines like The Saturday Evening Post, Time, and many women's magazines. Reminding the public of the services provided engendered...

Radio Training Association of America

Radio Training Association of America Ad, June 1932 Radio-Craft - RF CafeImagine having a serviceman of any sort arrive at your house, fix your problem, and present you with a bill of $6 - parts included. He would walk away satisfied that he had done a good job and was well compensated for the work considering the effort invested in training and qualification. $6 in 1932 when this Radio Training Association of America ad appeared in Radio−Craft magazine, per the Bureau of Labor Statistics' Inflation Calculator is worth $135 in 2023 money - that's a cheap service call even in today's economy. Further, the $14 stated as a day's earnings is $316 in 2023, which equates to 50 work weeks/year x 5 days/week x $316/day = $79,000/year - not too shabby. Just between you and me, that's more than I'm currently making per year...

Flow Batteries Replace Lithium

Flow Batteries Replace Lithium - RF CafeA new paradigm in EV battery recharging, known as a "flow" cell is in the works. Per this IEEE Spectrum magazine article, one variation on the flow battery is one where spent electrolyte is replaced rather than recharging the battery. "Flow batteries are safe, stable, long-lasting, and easily refilled, qualities that suit them well for balancing the grid, providing uninterrupted power, and backing up sources of electricity. This battery, though, uses a completely new kind of fluid, called a nanoelectrofuel. Compared to a traditional flow battery of comparable size, it can store 15 to 25 as much energy, allowing for a battery system small enough for use in an electric vehicle and energy-dense enough to provide the range and the speedy refill of a gasoline-powered vehicle." When recharging - or replenishing more accurately - spent nanofluid is exchanged for fresh nanofluid, which unlike lithium will not explode. The article does not mention the transportation and processing costs (both monetarily and ecologically) of making nanofluid available to tens of thousands of charging stations, including home-based ones. Still, it's better than the Earth's growing lithium stain. BTW, have you seen many EV charging stations with roofs over them? EVers get wet electrical connections when it's raining.

Anritsu and EMITE OTA Measurements on Wi-Fi 7

Anritsu and EMITE Supporting OTA Measurements on IEEE 802.11be (Wi-Fi 7) Devices - RF CafeAnritsu Corporation and EMITE announce enhanced functionality to their Over-the-Air (OTA) measurement solution, allowing measurements in compliance with the latest Wireless LAN IEEE 802.11be standard. IEEE 802.11be is being standardized as the successor to IEEE 802.11ax (Wi-Fi 6/6E) and is targeted to realize high-speed communications that significantly exceed IEEE 802.11ax. The standard is expected to be a fundamental technology supporting the latest applications and services, such as ultra-high-resolution video streaming beyond 4K and AR/VR. Anritsu's Wireless Connectivity Test Set MT8862A has been integrated with all portfolio of EMITE Anechoic and Reverberation Chambers, allowing developers to measure the OTA Total Radiated Power (TRP)/Total Isotropic Sensitivity...

Television in Germany

Television in Germany, December 1937 Popular Mechanics - RF CafeWhat's the big deal about television in Germany, you might ask? Today, it is no big deal, but in 1937 when this article appeared in Popular Mechanics magazine, it was. Philo Farnsworth and Vladimir Zworykin had only recently demonstrated their all-electronics TV systems, and the battle was on to decide whether the electromechanical systems that used rotating disks and/or mirrors, or the electronic-only types would emerge victorious. Communications standards committees were evaluating and hotly debating the pros and cons of each. Multiple all-electronic television system schemes contended as well. Each country and/or area in the world generated their own set of standards, so manufacturers who serviced worldwide markets needed to accommodate more than one system. Shortly after B&W broadcasting finally settled out, color TV thrust the industry and government regulators into another round of contentious competition. This story reports on Germany's efforts to bring television to its citizens - as it is preparing to start World War II...

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...

Monday the 25th

Message from Apollo 8, Christmas Eve, 1968

Earthrise Commemorative Stamp - Airplanes and RocketsWhile orbiting the Moon on Christmas Eve, 1968, NASA astronauts Frank Borman, Jim Lovell, and William Anders made a live broadcast from from the Apollo 8 command module, in which they showed video of the lunar surface and the Earth as seen from one of the spacecraft's portals. That flight produced the famous "Earthrise" photograph which is featured on a U.S. commemorative stamp issued in May of 1969 - just three months before Apollo 11 landed on the moon. On the ninth orbit, toward the end of the transmission, the three astronauts each took a turn reading from the book of Genesis, chapter 1, verses 1 through 10. They finished with, "And from the crew of Apollo 8, we close with good night, good luck, a Merry Christmas – and God bless all of you, all of you on the good Earth."

From Melanie and me here at AirplanesAndRockets.com, we wish you all a very Merry Christmas and a happy and prosperous New Year!

Gilbert Erector Set from 1969 Sears Christmas Wish Book

Gilbert Erector Set from the 1969 Sears Christmas Wish Book - Airplanes and RocketsOn page 511 of the Sears 1969 Christmas Wish Book are a few Erector Sets. This was probably the year (±a couple) that I got my first Erector Set. This was a step up from the Tinkertoy sets I previously owned. While not the largest set made, it had quite a lot of parts, including a motor. Although I already had a natural interest in assembling and - to my parents' dismay - disassembling stuff, it was gifts like this that really helped nurture what would become a life-long pursuit of things mechanical and electrical, eventually leading to my earning an electrical engineering degree. I remember getting a pretty good finger pinch by one of the motorize contraptions I built. Show above is Erector Set #3, similar to the one I received for Christmas in 1969. This one I bought on eBay since, as with most things I owned, the original did not survive my handling...

Many Thanks to Anatech Electronics for Long-Time Support!

Anatech Electronics logo - RF CafeAnatech Electronics (AEI) manufactures and supplies RF and microwave filters for military and commercial communication systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard RF filter and cable assembly products are published in our website database for ease of procurement. Custom RF filters designs are used when a standard cannot be found, or the requirements dictate a custom approach for your military and commercial communications needs. Sam Benzacar's monthly newsletters address contemporary wireless subjects. Please visit Anatech today to see how they can help your project succeed. 

Sunday the 24th

Electronics Theme Christmas 2023 Crossword Puzzle

Electronics Theme Christmas Crossword Puzzle for December 24th, 2023 - RF CafeThis Electronics theme Christmas Crossword Puzzle for December 24th has many words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects, along with a holiday message. There is also a holiday greeting contained within. 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., Reginald Denny or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

Friday the 22nd

WWV's Sharp Tunes Keep World in Step

WWV's Sharp Tunes Keep World in Step, July 1949 Popular Science - RF CafeBack in the 1970s and 80s when I was a regular reader of magazines like Popular Science, Mechanix Illustrated, Popular Mechanics, et al, it never occurred to me that there were so many stories and news tidbits related to electronics and communications. Now, half a century later as I read through many of them, I am amazed to see just how much content there is for posting on RF Cafe. Of course I was nowhere near as familiar with the topics at the time, so the stories did not have the draw they do now. Just as with the contemporary magazines I peruse each month, I typically go through them from cover to cover, reading much of what is there, including the advertisements. This 1949 report is on the National Bureau of Standards' (NBS, now National Institute of Standards and Technology, NIST) frequency and timing standard signals from their original location near Washington, D.C., call sign WWV. Details on the various continually broadcasted signals are covered within, along with some of the equipment used to accomplish the feat. You will need to visit the current WWV website to compare with today's signals...

Terminal Radio Christmas and New Year Greeting

Terminal Radio Corp. Christmas and New Year Greeting, January 1941 QST - RF CafeOther than today's QST magazine being a larger format and being printed in full color, there is not much difference fundamentally between the amount of Christmas-themed company advertisements now and half a century ago. The January 2024 (out now) issue of QST is chock full of Christmas-themed ads. Those from the last century were more likely to incorporate a religious message in addition to or instead of a secular message to their customers. Terminal Radio Corporation was located in midtown Manhattan. Google Maps can find West 45th Street and it can find Cortlandt Street, but they evidently no longer intersect. Many component supply companies were located in New York City because it was a primary point of import and export of manufactured goods...

Please Thank IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products has been designing and manufacturing RF and Microwave passive components since 2005. We use the latest design tools available to build our baluns, 90-degree couplers, directional couplers, combiners/dividers, single-ended transformers, resistors, terminations, and custom products. Applications in military, medical, industrial, and commercial markets are serviced around the world. Products listed on the website link to detailed mechanical drawings, electrical specifications, and performance data. If you cannot find a product that meets your requirements on our website, contact us to speak with one of our experienced design engineers about your project.

The Christmas Equation

The Christmas Equation - RF CafeAn RF Cafe visitor sent this equation to me a few years ago. It can be found all over the Internet (including here), but I cannot determine a definite origin. Mathematicians claim that math can explain everything in the universe, which is not quite true. It can't for example, explain why my next-door neighbor is a junk hoarder. This Christmas equation does not appear to begin with a particular application; it looks like something from a set of textbook end-of-chapter problems. Even if you don't celebrate Christmas, it provides a secondary benefit by demonstrating rules for the manipulation of logarithms and exponents along with basic algebraic rearrangements of terms.

After Class: Resistor and Capacitor Combinations

After Class: Resistor and Capacitor Combinations, June 1955 Popular Electronics - RF CafeHere is a short tutorial on resistor-capacitor (R-C) combinations and the time constants created by their combinations. It's pretty basic stuff, but there are new people coming into the field of electronics all the time so it is worth posting. Discussed are coupling circuits, filter networks, differentiators, and time-delay circuits. The "After Class" feature is a series run by Popular Electronics magazine in the 1950s and 1960s. As with this installment, "After Class" presented topics on electricity and magnetism that served not just as new material for beginners, but was a good review even for seasoned practitioners of the craft. A complete list of all the "After Class" articles I have posted is listed below...

Thanks to TotalTemp Technologies for Continued Support!

TotalTemp Technologies - RF CafeTotalTemp 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.



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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...

Copyright  1996 - 2026

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website: AirplanesAndRockets.com

My Daughter's Website: EquineKingdom

KR Electronics (RF Filters) - RF Cafe

withwave microwave devices - RF Cafe

Innovative Power Products Passive RF Products - RF Cafe