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Homepage Archive - June 2023 (page 1)

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

Wednesday the 7th

Electronics-Themed Comics

Electronics-Themed Comics (p69), April 1961 Radio-Electronics - RF CafeHere be a new trio of tech-themed comics, this time from the April 1961 issue of Radio-Electronics magazine. The one on page 69 is my favorite. In the page 85 comic, there is a squarish "U" shaped line between the one guy's finger and the other guy's elbow, and I can't figure out what it is supposed to be. What am I missing? The page 96 comic is kinda dumb. Did people refer to that form of antenna as an "antler" back in the day? A firm called MCM Manufacturing Company, in Fort Worth, Texas, made a line of mobile antennas and support products (mounts, cables, etc.) called Antler CB Antennas, but from what I can find they didn't come into being until the 1970s. The advertisement shown here appeared in a 1977 issue of Popular Electronics magazine. Maybe I missed something...

Cold Cathode Tube Demonstrated

Cold Cathode Tube Demonstrated!, January 1935 Short Wave Craft - RF CafeCold cathode tubes are distinguished from hot cathode tubes in that they do not use a separate heated element in order to generate free electrons (thermionic heating). Rather, a "starter" type process is used to initiate the electron generation and then a cascade multiplication keeps the process running. Although this 1935 Short Wave Craft magazine article reports on a cold cathode oscillator vacuum tube - designed by none other than television pioneer Philo Farnsworth - some more familiar examples are neon and fluorescent bulbs and even the veritable Nixie tube...

Forksheet: Imec's In-Between Transistor

Forksheet: Imec's In-Between Transistor - RF Cafe"The architecture shrinks circuits in a valuable step toward the ultimate CMOS device. The most advanced manufacturers of computer processors are in the middle of the first big change in device architecture in a decade - the shift from finFETs to nanosheets. Another 10 years should bring about another fundamental change, where nanosheet devices are stacked atop each other to form complementary FETs (CFETs), capable of cutting the size of some circuits in half. But the latter move is likely to be a heavy lift, say experts. An in-between transistor called the forksheet might keep circuits shrinking without quite as much work. The idea for the forksheet came from exploring the limits of the nanosheet architecture, says Julien Ryckaert, the vice president for logic technologies at Imec. The nanosheet's main feature is its horizontal stacks of silicon ribbons surrounded by its current-controlling gate. Although nanosheets only recently entered production..."

Find the Brightest Bulb Quiz

Find the Brightest Bulb Quiz, April 1960 Popular ElectronicsHere is a nifty little exercise that appeared in the April 1960 edition of Popular Electronics magazine. The "Find the Brightest Bulb Quiz" has ten different light bulb circuits and challenges you to figure out which bulb would burn the brightest. All are intuitively obvious to most of us who have been in the field for decades, but do you remember how to do a circuit mesh analysis to prove your "gut?" One way to help figure out what is going on is to re-draw the circuit to eliminate crossing lines, if possible, as in circuit numbers 2, 4, 6, and 10. Also try drawing electrically common nodes as a single connection point, as in circuit #2 where the two nodes in the upper left and right corners are actually the same point. Finally, try to re-arrange the circuit branches into obvious parallel and series paths to make clear any interdependencies and independencies...

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...

Thanks Again to Aegis Power Systems for Continued Support!

Aegis Power Systems - RF CafeAegis Power Systems is a leading supplier of AC-DC and DC-DC power supplies for custom and special applications. Aegis has been designing and building highly reliable custom power supplies since 1995. They offer a complete line of switch mode power supplies and power converters for a variety of markets including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft, EV, telecom, and embedded computing applications. Design and manufacture of custom power supply solutions to meet each customer's exacting specifications. Please visit Aegis Power Systems today. Manufactured in the USA.

Tuesday the 6th

Antenna Rotators

Antenna Rotators, April 1968 Radio-Electronics - RF CafeThe purpose of directional antennas is not just to increase gain along a particular radial in order to enhance weak signals, but also to reduce gain in all other directions so as to minimize interference. Interference can be both signals from unrelated emitters and from multipath signals that originated from the same emitter. Hence, a directional antenna can be advantageous in an environment where a relatively strong signal from the intended emitter is surrounded by other strong signals. Even if the interfering signals are not on the same frequency, the effect of raising the overall noise floor and/or generating intermodulation products can degrade the intended signal significantly enough to bugger audio and/or video. The solution is to mount the receiving antenna on a rotator so that it can be pointed in a direction which results in the best signal. Here is my Alliance U-100 Tenna−Rotor write−up with photos...

Electron Mobility Faster in GeSn Than Si or Ge

Electron Mobility Faster in GeSn Than in Si or Ge - RF Cafe"Electrons and other charge carriers can move faster in germanium tin than in silicon or germanium, enabling lower operation voltages and smaller footprints in vertical than in planar devices, say CEA-Leti researchers. This proof-of-concept breakthrough means vertical transistors made of germanium tin are promising candidates for future low-power, high-performance chips and possibly quantum computers. GeSn is otherwise compatible with the existing CMOS process for chip fabrication. Because germanium and tin come from the same periodic table group as silicon, these transistors could be integrated directly into conventional silicon chips with existing production lines. 'In addition to their unprecedented electro-optical properties, a major advantage of GeSn binaries is also that they can be grown..."

Ionospheric-Propagation Predictions

Ionospheric-Propagation Predictions, April 1969 Electronics World - RF CafeMuch has been learned and published about the various layers of the ionosphere since its first being measured with sounding rockets in the 1950s. Both professional and amateur communications operators are very interested in its properties. Long term (seasonal) and short term (daily) patterns have been discerned that help make some of the ionosphere's effect on the propagation of electromagnetic (radio) signals somewhat predictable, but there are still many unpredictable events that hamper - and often enhance - communications. Sun spots and coronal mass ejections, volcanic eruptions, hurricanes, and other natural events cause sporadic changes in the ionosphere. Real-time atmospheric propagation conditions are monitored and reported on many websites worldwide...

Antenova Pharaoh: Big Step in 4G/LTE Antennas

Antenova Pharaoh: A Big Step Forward in 4G/LTE Antennas - RF CafeAntenova Ltd, the UK-based manufacturer of antennas and RF antenna modules for M2M and the IoT, is delighted to introduce you to Pharaoh (SR4L073): the perfect antenna for your next 4G or 5G project. Pharaoh is a switch-free, surface-mount (SMD) antenna which is designed to unlock the full potential of LTE performance on limited ground planes. Pharaoh represents a significant breakthrough in 4G/LTE antenna technology that promises to hugely improve what is possible for devices with limited PCB real estate. This is why: Maximising Performance Rather than being a tiny antenna requiring a large ground plane, Pharaoh enables you to shrink the overall footprint on your design while enabling strong performance across every 4G/LTE band including the very lowest. Gaining Certification Faster Achieving certification for the smallest 4G/LTE devices can be an expensive and time-consuming process. Pharaoh has been proven by an independent PTCR...

Derivation of Phase Angle Error Due to VSWR Mismatch

Derivation of Phase Angle Error Due to VSWR Mismatch - RF CafeTry finding the equation for phase angle error due to VSWR mismatch, and you will likely fail. Extensive keyword searches for related terms will turn up websites that present the formula for amplitude error due to VSWR mismatch, but not for phase angle error due to VSWR mismatch. If you are fortunate enough to find the equation, you almost certainly will not be given the derivation. The actual equation, εθmax = |Γ1 | • |Γ2|, is so simple that it seems unbelievable, but here its validity is demonstrated. Well, the search is over thanks to Haris Tabakovic, who was kind enough to provide this excellent derivation for the benefit of RF Cafe visitors...

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Sponsor RF Cafe for as Little as $40 per Month - RF CafeNew Scheme rotates all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000 website visits each weekday. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 17,000 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. If you need your company news to be seen, RF Cafe is the place to be.

Many Thanks to Berkeley Nucleonics for Continued Support!

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

Monday the 5th

Power Dissipation in Resistors or Transistors

Power Dissipation in Resistors or Transistors, August 1963 Radio-Electronics - RF CafeCharts and nomographs are not nearly as useful or necessary today for the design and troubleshooting of electronics due to the ready availability of calculators in the form of computers, tablets, and smartphones. Determining parallel and series resistance, capacitance, and inductance, reactance, power dissipation, resonant frequency, voltage dividers, etc., can easily be done with the push of a few buttons (or virtual touch-sensitive screen buttons). Not only is it not necessary to know the equations behind the calculations, but you don't even need the know how to enter mathematical operations into a calculator. A lot of old-schoolers say the availability of newfangled electronic gizmos contributes to the dumbing down of technicians and engineers. If you can't use a slide rule, then you don't truly understand the science. I wonder if their attitudes were the same when special-purpose cardboard slide calculators and even design charts like this one and nomographs were published?

Ceramic Filters

Ceramic Filters, April 1969 Electronics World - RF CafeThe introduction of low cost, small-footprint ceramic filters were unquestionably a boon to efforts at reduction in end-product package size and manufacturing cost. Very good Q and selectivity, no tuning required, and good temperature stability made them perfect for use as IF filters in broadcast radio receivers, at 10.7 MHz (FM) and 455 kHz (AM). They became available for commercial use around 1960. This publically available paper published in 2000 from the IEEE provides some historical perspective to ceramic filters: The History of Ceramic Filters, by Satoru Fujishima. The Clevite Corporation, for which this Electronics World author, Reg Zimmerman worked, is mentioned in the IEEE paper, as is Murata, for being pioneers in the ceramic filter field...

Nanostructure Flat Lens for Tiny Cameras

Nanostructure Flat Lens for Tiny Cameras - RF Cafe"Inside today's computers, phones, and other mobile devices, more and more sensors, processors, and other electronics are fighting for space. Taking up a big part of this valuable real estate are the cameras - just about every gadget needs a camera, or two, three, or more. And the most space-consuming part of the camera is the lens. The lenses in our mobile devices typically collect and direct incoming light by refraction, using a curve in a transparent material, usually plastic, to bend the rays. So these lenses can't shrink much more than they already have: To make a camera small, the lens must have a short focal length; but the shorter the focal length, the greater the curvature and therefore the thickness at the center. These highly curved lenses also suffer from all sorts of aberrations, so camera-module manufacturers use multiple lenses to compensate, adding to the camera's bulk. With today's lenses, the size of the camera and image quality are pulling in different directions. The only way to make lenses smaller and better is to replace refractive lenses with a different technology..."

Practical Applications of Simple Math

Practical Applications of Simple Math - Part II, June 1944 QST - RF CafeRecognizing that many people were reluctant to approach the theoretical aspect of electronics as it applied to circuit design and analysis, QST (the American Radio Relay League's monthly publication) included equations and explanations in many of their project building articles. Occasionally, an article would be published that dealt specifically with how to use simple mathematics. In this case, the June 1944 edition, we have the second installation of at least a four-part tutorial that covers resistance and reactance, amplifier biasing (tubes since the Shockley-Bardeen-Brattain trio hadn't invented the transistor yet) oscillators, feedback circuits, etc. I do not have Part I from the May 1944 edition or Part IV from the August 1944 edition, but if you want to send me those editions, I'll be glad to scan and post them...

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 Amplifier Solutions Corporation (ASC) for Continuing Support!

Amplifier Solutions Corporation (ASC) - RF CafeAmplifier Solutions Corporation (ASC) is a manufacturer of amplifiers for commercial & military markets. ASC designs and manufactures hybrid, surface mount flange, open carrier and connectorized amplifiers for low, medium and high power applications using Gallium Nitride (GaN), Gallium Arsenide (GaAs) and Silicon (Si) transistor technologies. ASC's thick film designs operate in the frequency range of 300 kHz to 6 GHz. ASC offers thin film designs that operate up to 20 GHz. ASC is located in an 8,000 sq.ft. facility in the town of Telford, PA. We offer excellent customer support and take pride in the ability to quickly react to evolving system design requirements.

Sunday the 4th

Electronics Theme Crossword Puzzle for June 4

Electronics Theme Crossword Puzzle for June 4, 2023 - RF CafeThis week's crossword puzzle for June 4th sports an electronics theme. This being the fourth day of the month, many of the words begin and/or end with the letter "D." Besides that, we're only two days away from "D-Day." 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!

Please Support RF Cafe

Amazon Prime - RF CafeThe RFCafe.com website exists partly on the support of its visitors by way of a small percentage earned with your Amazon.com purchases, which typically works out to less than $20 per month. That does not even cover the domain registration and secure server fees for RFCafe.com. If you plan to buy items via Amazon.com, please click on this link to begin your shopping session from here so that I get credit for it. Doing so does not cost you anything extra. Thank you for your support.

Thanks to Exodus Advanced Communications for Continued 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.

Friday the 2nd

Fuses Are Not for Confusion

Fuses Are Not for Confusion, October 1960 Electronics World - RF CafeBack in the early 1990s I had my first need as a product design engineer to select a fuse type; it was for protecting a downconverter chassis. Having already worked in the electronics and electrical equipment installation and maintenance field for twenty years, I have had to replace many fuses of many different types in many types of assemblies ranging from AC motor controls to microprocessor boards. Slo−Blo, Fast−Blo, Standard−Blo, high voltage and low voltage, high current and low current, glass bodied, plastic bodied, and even metal explosion-proof bodied fuses were in the realm my experience. However, some other engineer had already decided what the appropriate fuse was for the application. I assume each instance had been determined from a selection process based on knowledge of both the device to be protected and the characteristics of the fuses. Not just any fuse will do the job. Sometimes you get lucky and the one used will work so long as the current and voltage ratings are within the normal operational range of the product being protected, but if that was generally the case, there wouldn't be such a large variety of fuse types, n'est−ce pas? This "Fuses Are Not for Confusion" article from a 1960 issue of Popular Electronics magazine is a great primer on the art of fuse selection...

Alternative Energy: Savior to an Alternate Universe

Alternative Energy: Savior to an Alternate Universe - RF Cafe SmorgasbordA few years ago, my local newspaper, Erie Times-News, printed this letter that I submitted: "As an electrical engineer, I have always embraced the technology behind wind, hydro, solar and other forms of 'alternative' energy production. It is undoubtedly cool. What I despise is an agenda by special interest groups to mislead the public regarding the maturity and efficiency of those systems in an effort to destroy the nuclear and fossil fuel industries that drive our economy. The recent failure of the 5-year-old wind turbine at Tom Ridge Environmental Center is a good example. Numbers were not provided for that turbine, but were for the one on Barracks Beach, also offline (Erie Times-News, March 31). The turbine and tower cost about $36,000 in 2004 dollars, when installed. The stated best-case energy generation for it is 15,000 kwh/ year. Electricity rates around here are about 13 cents/kwh...

Following the Science ... Dr. David Martin

Dr. David Martin, at the International COVID Summit | 2003 European Parliament - RF CafeRegardless of your position on the appropriateness of actions taken by world governments and private entities regarding the COVID 19 debacle, if you truly do "believe the science" as we were all admonished to do, then you are obligated to avail yourself of validated, relevant data. Those of us who had researched the issue and arrived at our own conclusions early on were routinely condemned and demonized for daring to buck the official narrative. By all accounts we should have expired long ago from the virus while the believers enjoy practically eternal life from being vaxxed ... and revaxxed ... and revaxxed... Seems the opposite has happened. Sadly, many people still have not exposed themselves to information from other than the perpetrators of the deed. This presentation by Dr. David Martin, at the International COVID Summit | 2023 European Parliament will shock you (~15 minutes) regardless of your beliefs. The level of deception and lying has been epic - with catastrophic results. If you still enthusiastically support the official narrative, fear not, your heroes will not face any penalty. How many weeks will be needed next time to "flatten the curve?"

Simpson Electric Company 260 VOM

Simpson Electric Company Advertisement Model 260 VOM, July 1944 QST - RF CafeI was first introduced to the Simpson 260 volt-ohmmeter (VOM) in the radar shop where I was assigned in the USAF. Here is the modern version of that classic, the Simpson 260-8 VOM; it looks a lot like the original. Here is an advertisement that I scanned out of my copy of the July 1944 QST magazine. It highlights the precision to which its meter movement pivots are manufactured. "While Simpson Electric Company, chartered in 1934, is a firm with a distinguished past, it is just as importantly an organization with a dynamic present and a definite future." There is an entire website dedicated to the history of the Simpson 260. The famous 260 Volt-Ohm-Milliammeter put Simpson on the map and cemented a reputation for quality that still defines Simpson in the marketplace today." You can still buy a brand new Simpson 260 (-8) from Amazon - and it isn't cheap - or grab a vintage Simpson Model 260 on eBay for under $100...

Werbel 2-Way Power Divider 0.5-6 GHz

Werbel Microwave 2-Way Power Divider 500 MHz to 6 GHz - RF CafeWerbel Microwave, a designer and manufacturer of RF and microwave power couplers, dividers, terminations, and DAS equipment, introduces the Model D−2065−N from Werbel Microwave is a 2−way power splitter covering the continuous bandwidth of 500 MHz to 6 GHz. The product features low insertion loss of 0.9 dB, high isolation of 22 dB and excellent return loss performance of 19 dB. Tight phase and amplitude matching between outputs. Aluminum body with stainless steel N(F) connectors. Small size, only 0.75 in thick, allows for dense stacking in tight spaces. Werbel Microwave's catalog of directional couplers and power splitters / combiners are high performance at an affordable price point. Our original design. Click here for the C-9001-8.5 spec sheet. About Werbel Microwave In-House Manufacturing Capability Werbel Microwave started in 2014 humbly working out of a one-car garage. Since then we have grown to occupy a 1300 square foot office and shipped over 10,000 products to date...

Electronics Inventors Quiz

Electronics Inventors Quiz, November 1963 Popular Electronics - RF CafeMost of these matches of the devices and its inventor are pretty easy for people who have been around electronics for any length of time (well, not if the length of time is only a day or two), but there are a couple that just might stump you. This "Electronics Inventors Quiz" appeared in the November 1963 issue of Popular Electronics magazine, so you won't be challenged with knowing the inventors of the LCD or MEMS devices, but neither will you have to know who came up with the abacus or the Archimedes screw :-). I managed to score 100%, but that was admittedly partly luck in deciding between two men for items "B" and "C." The other eight should be a piece of cake for most RF Cafe visitors...

RF & Electronics Symbols for Visio

RF Electronics Wireless Analog Block Diagrams Symbols Shapes for Visio - RF CafeWith more than 1000 custom-built symbols, this has got to be the most comprehensive set of Visio Symbols available for RF, analog, and digital system and schematic drawings! Every object has been built to fit proportionally on the provided A-, B- and C-size drawing page templates (or can use your own). Symbols are provided for equipment racks and test equipment, system block diagrams, conceptual drawings, and schematics. Unlike previous versions, these are NOT Stencils, but instead are all contained on tabbed pages within a single Visio document. That puts everything in front of you in its full glory. Just copy and paste what you need on your drawing. The file format is XML so everything plays nicely with Visio 2013 and later...

Many Thanks for Alliance Test Equipment's Support!

Allied Test Equipment Products - RF CafeAlliance Test Equipment sells used / refurbished test equipment and offers short- and long-term rentals. They also offer repair, maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP, Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization with ability to source hard to find equipment through our network of suppliers. Alliance Test will purchase your excess test equipment in large or small lots. Blog posts offer advice on application and use of a wide range of test equipment. Please visit Allied Test Equipment today to see how they can help your project.

Thursday the 1st

Channel Master Antennas

Channel Master Antennas, October 1960 Electronics World - RF CafeThe decade of the 1960s was probably the heyday of television. Household incomes had been steadily rising since the end of World War II while inflation was relatively low. The Korean War was over and until around 1965 the country was not on a serious war footing. Game shows, soap operas, shows depicting non-dysfunctional families, variety show formats, non-woke cartoons, movies, and newscasts that didn't insult half the country with biased coverage fed the country's appetite for wholesome, useful entertainment. Once violent race riots and hippie anti-establishment protests became a major threat to safety and civic deportment, people monitored radio and television to keep abreast of events. In accord with rapidly improving television sets were advances in antenna technology. Viewers wanted the best possible picture and audio, and were willing to pay dearly for it. Through around the end of the 20th century, after which cable dominated as a transmission medium, over-the-air broadcasts in increasingly crowded RF environments made higher performance antennas even more necessary...

Compliant 3D-Printed Tunable GHz-Range Antenna

Compliant 3D-Printed Tunable GHz-Range Antenna - RF Cafe"Many situations arise in which an antenna needs to dynamically reconfigure its center frequency or beam pattern. In some cases, this can be done with a steerable, multi-element antenna array, but it's often not a viable solution for various reasons. As an alternative, a team of electrical engineers in the Penn State College of Engineering devised an innovative design for a reconfigurable patch antenna dubbed a reconfigurable compliant mechanism antenna (rCMA). The antenna, which leverages the inherent elastic properties of selected material to create a desired motion through controlled deformation, is designed to operate up to 10 GHz. These compliant mechanisms can be made as a planar structure from a single material yet still achieve multi-axis motion. Further, they can be designed as a full structure with minimal or even no assembly, require no lubrication, and their reliability is high, as it's based on the elastic properties of the material..."

War and the Radio Amateur

War and the Radio Amateur, May 1917 The Electrical Experimenter - RF CafeAmateur radio station operators seemed to always be amongst the first to lose their rights in time of war. Governmental power brokers - from unelected local bureaucrats on up to presidents - love to demonstrate their influence over citizens when the opportunity arises. The Radio Act of 1912 revoked the rights of amateur radio stations to operate, and in some cases authorized the confiscation of radio equipment for use by the government. Permission was not restored until 1919, after World War I. Amateurs took it on the chin again in World War II with revocation of licenses. In this 1917 article in The Electrical Experimenter magazine publisher Hugo Gernsback makes the case for permitting "our red-blooded boys be trusted to assist our officials in running down spies." "...we realize how absurd it is to close all privately owned radio stations during the war," says he. It fell on deaf ears, as usual. As the now mayor of Chicago once famously said, "You never want a serious crisis to go to waste..."

Anatech Intros 3 Filter Models

Anatech Electronics Intros 3 Filter Models for May 31st, 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 models have been introduced - a 1176 MHz / 1575 MHz ceramic duplexer with an 18 MHz minimum bandwidth, a 1616 - 1626.5 MHz cavity bandpass filter with TNC female connectors, and a 4900 MHz bandpass filter with N-type male / N-type female connectors. 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...

Electronics and IGY

Electronics and IGY, March 1958 Popular Electronics - RF CafeThe International Geophysical Year (IGY) was an international scientific project that took place from July 1, 1957, to December 31, 1958. It was a collaborative effort involving scientists from around the world to conduct research in various fields of geophysics. The IGY was organized in response to a proposal by the International Council of Scientific Unions (ICSU) to promote international cooperation in the study of the Earth and its environment. The project aimed to advance our understanding of Earth's physical properties, including its atmosphere, oceans, and solid Earth. During the IGY, scientists conducted research in a wide range of disciplines, such as meteorology, seismology, glaciology, oceanography, and solar physics. They used cutting-edge technologies and established numerous research stations across the globe to gather data. One of the most significant achievements of the IGY was the International Geophysical Year Antarctic Program. Several countries established research bases in Antarctica, leading to significant discoveries about the continent's geology, weather patterns, and wildlife...

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!

Many Thanks to Withwave for Long−Time Support!

Withwave RF & Microwave Components - RF CafeWithwave manufactures an extensive line of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch, board edge, panel mount), calibration kits (SOLT), a fully automated 4-port vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures for calibration and multicoax cable assemblies. Frequency ranges from DC through 110 GHz. Please contact Withwave today to see how they can help your project succeed.

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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