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Homepage Archive - April 2022 (page 2)

See Page 1 | 2 | 3 | 4  of the April 2022 homepage archives.

Thursday the 14th

Industrial Chemistry - It Meets Demands of War

Industrial Chemistry - It Meets Demands of War, March 23, 1942 Life - RF CafeIn 1942 and throughout the War Years, Life magazine (and many others) ran many articles promoting industries, services, organizations, and individuals who contributed toward our ultimate victory. Of course no one knew for certain that we would prevail in the end, but if it hadn't turned out that way, it wouldn't have been for lack of effort and sacrifice. Part of the objective was to inform the populace about how the country was pooling its resources - physical, labor, and mental - to defeat the Axis Powers that sought to takeover the world. This particular issue of Life focused on the chemical industry, with the raw materials and processes used to produce needed products both for fuel and for the base components of other finished goods. Sulphur, potassium, and coal mining and processing, along with petroleum, common table salt, and air and water were some of the most fundamental ingredients of every other item needed to aid the effort. Ever hear of Ameriopl rubber?

Loopy Currents Appear in Kagome Superlattice

Loopy Currents Appear in Kagome Superlattice - RF Cafe"Exotic materials known as kagome superconductors can play host to a rare state of matter in which electric currents form 'loops' around unit cells in the material’s crystalline lattice. This discovery, made by researchers at Switzerland's Paul Scherrer Institute (PSI) together with international collaborators, could reveal new information about how superconductivity emerges in materials where complex effects such as frustrated magnetism and intertwined orders play a major role. Kagome metals are named after a traditional Japanese basket-weaving technique that produces a lattice of interlaced, corner-sharing symmetrical triangles. When the atoms of a metal or other conductor are arranged in this so-called kagome pattern, their electrons behave in unusual ways, giving rise to interaction-driven electronic phases of matter that can be identified by studying symmetries of the material. In one such electronic phase, electrons organize themselves into a looped pattern along the kagome bonds between regions of the lattice with high and low concentrations of electric charge..."

FM Radio in Canada

FM Radio in Canada, January 1946 Radio News - RF CafeDepending on which news story you believe, both AM and FM (and television for that matter) over-the-air broadcasting is dying out at an increasingly rapid rate. Between recordable podcasts, wired Internet connections, and the growing ubiquity of Wi-Fi connectivity, a large majority of people in the civilized world are getting their broadcasts via the Web. If you "follow the money" in broadcast advertising, the lion's share of dollars have shifted to online venues, simultaneously draining revenue from local stations. When this story was written in 1946, OTA radio was king for real-time and free reception of information - particularly in a mobile environment. A dilemma arose in the form of RF spectrum allocation in border regions between the U.S. and Canada, both of which were scrambling to stake a claim on channels. AM was old-hat and sharing issues had largely been worked out, but the advent of FM (frequency modulation) and an entirely new band of frequencies opened a real can of worms for national and international regulators...

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...

Many Thanks to Axiom Test Equipment for Continued Support!

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

Wednesday the 13th

Bell Telephone Laboratories Klystron

Bell Telephone Laboratories Klystron, May 1956 Radio-Electronics - RF CafeThe Varian brothers, Russell and Sigurd, are widely credited for invention of the klystron around 1937. Credit for further developments in the klystron - from its technology to origin of the name - is a bit fuzzy based on many articles I have seen. According to a 1944 Radio News magazine article, Sperry Gyroscope Company developed the tube into commercial viability and was assigned the trademark name "klystron" based on their creation of the field of "klystronics." However, the Wikipedia entry for Stanford professor Hermann Fränkel claims the name "klystron" was suggested by him. This full-page Bell Telephone Labs promotion in a 1956 issue of Radio-Electronics magazine tells of their 60 GHz klystron design by employee G.K. Farney, but makes no mention of the device's history. Bell Labs is unquestionably responsible for untold numbers of paradigm-changing inventions, but for some reason the omission of that information - especially so close in time to the klystron's arrival on the commercial scene - bothers me a bit...

U.S. Naval Laboratory 3D Prints Antennas and Amplifiers

U.S. Naval Research Laboratory 3D Prints Antennas and Amplifiers - RF Cafe"The U.S. Naval Research Laboratory (NRL) Electronics Science and Technology Division (ESTD) actively performs research and development in a variety of materials science, physics, and engineering fields pursuing technological advances crucial to the DoD future high-performance electronic systems. Research topics span all aspects of electronics, such as advanced fabrication methods for radio frequency (RF) devices, growth and characterization of exotic electronic materials, quantum information science, neuromorphic computing, power devices and solar cells, nanofabrication, and solid state and vacuum electronic RF sources. 'NRL's ESTD aims to harness 3D printing for electromagnetics, such as antennas, metamaterials, and millimeter-wave with RF amplifiers operating in very high frequency bands, such as 5G and beyond,' said Alan Cook, Ph.D., Head of Vacuum Electronics and Material Section. 'With precision build capabilities of these machines ranging in resolution from small fractions of a millimeter down to the 100-nanometer scale, NRL's ESTD aims to foster DoD and Department of Navy concepts...'"

Astronomy and Amateur Radio

Astronomy and Amateur Radio, November 1943 QST - RF CafeIt is always nice to read an article that encompasses more than one of my hobbies, whether it be amateur radio and amateur astronomy like this one, amateur radio and model rocketry, or amateur radio and radio controlled airplanes. I don't recall ever seeing an article that combined astronomy and model airplanes. In this 1943 QST magazine piece, author Hollis French expounds on the necessity for Hams to understand the effects that atmospheric phenomena, caused primarily by our sun's periodic and intermittent activity, have on radio signal propagation. Properties of the ionospheric layers had by 1943 been pretty well surmised based on cause and effect relationships through indirect observation since at the time no sounding rockets had been launched into the upper atmosphere to obtain in situ measurements of ionization, magnetic fields, and free electron activity. Today's knowledge of course is much more detailed and formulated thanks in large part...

Many Thanks to Amplifier Solutions Corporation (ASC) for Continuing Support!

Amplifier Solutions Corporation (ASC) - RF Cafe 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.

The Old Radio Builder Website

The Old Radio Builder Website - RF CafeApril 2022 Update: Back in 2015, I ran across The Old Radio Builder website, hosted by Mike Starcher, KB4YJ, of Louisville, Kentucky. He has a nice collection of vintage radio restorations and building projects, all of which are useful to hobbyists. Sadly, I received word from a good friend (Gary F.) of Mike's that he is now a Silent Key, and was asked whether there is a way to get Mike's website back up since the Old Radio Builder website has been taken down. Fortunately, I discovered that the Archive.org website has many captures of the website's pages, so in effect it is still up and available! The last capture of The Old Radio Builder before it expired appears to be March of 2019. It lives on in perpetuity...

Comics with an Electronics Theme

Comics with an Electronics Theme in Popular Electronics Magazine - RF CafeHere are a few more tech-themed comics from older editions (1962 and 1970) of Popular Electronics magazine. The first comic with the transistors and fuse is really clever, IMHO. The other two are directed toward amateur radio operators, but you don't need to be one to appreciate the humor. There is a hyperlinked list at the bottom of the page of most of the other comics I've posted over the years. It's a shame that comics rarely appear in contemporary technical magazines - probably too afraid of offending someone...

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 (of course a gratuity will be graciously accepted). 3rd party recruiters and temp agencies are not included so as to assure a high quality of listings. Please read through the easy procedure to benefit from RF Cafe's high quality visitors ...

Many Thanks to Centric RF for Their Continued Support!

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

Tuesday the 12th

Mac's Radio Service Shop: Mending Harness

Mac's Radio Service Shop: Mending Harness, October 1950 Radio & Televsion News - RF CafeThis episode of "Mac's Radio Service Shop" is a prime example of the difference between a business owner and an employee when it comes to always thinking about how to make things more efficient and attractive to customers - and therefore more profitable. To be fair, there is no reason to expect an employee to have as high a level of devotion as an owner other than for better job security. The October 1950 story entitled "Mending Harness," appearing in Radio & Television News magazine, is a prime example. Mac, the proprietor, had spend many hours in the evenings completing service jobs and clearing the shop of its sizeable backlog. Barney, the employee, loved the situation since he thought it would mean some slack time for him. Mac, though, planned to use that time for repairing, aligning, and improving the test equipment - something that had gone wanting during the busy times. As always, Mac's Service Shop docu-dramas are a good mix of useful lessons and good humor...

Anatech Intros 3 Filter Models for Mid April

Anatech Electronics Intros 3 Filter Models for Mid April 2022 - 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 0-450 MHz / 900-2100 MHz L-C diplexer with SMA connectors, a 824-891.5 MHz cavity bandpass filter with N-type connectors, and a 3.2 MHz L-C lowpass filter with SMA connectors. Custom RF power directional coupler designs can be designed and produced when a standard cannot be found, or the requirements are such that a custom approach is necessary...

Metasurface High-Efficiency Harvesting of RF Energy

Metasurface High-Efficiency Harvesting of Ambient RF Energy - RF Cafe"Energy harvesting, with its many manifestations, is often an attractive and viable solution to providing long-term low levels of operating dc power. RF-energy harvesting is especially attractive since that energy is pervasive, while capturing it incurs no discernable negative impact on intended users - it's truly 'going to waste.' Further, unlike many (but not all) fixed-in-place solar, vibration, or thermal-harvesting installations, most RF-harvesting arrangements can be mobile to go with system they're powering. Key to use of ambient RF energy as a harvestable source is the energy collector. It acts as a transducer to capture electromagnetic energy and transform it into useful electrical energy and power in the form of voltage and current. While a regular antenna can be used for this function - after all, that's what an antenna does - the capture efficiency is quite low and generally insufficient unless a fairly large and resonant antenna is used. Addressing this challenge, a team at the University of South Florida has developed a metasurface-based antenna..."

The Jodrell Bank Radio Telescope

The Jodrell Bank Radio Telescope, February 1958 Radio Electronics - RF CafeRadio astronomy has been the motivation for much research work in the design of low noise, high sensitivity receivers, but also in determining the characteristics of the Earth's upper atmosphere. Before sounding rockets could be launched to verify theoretical proposals, observed versus predicted behavior in radio signals being reflected off the moon and planets needed to be explained and, if necessary, corrected. One notable example of atmospheric perturbation is the rotation of polarization caused by electrons in the ionosphere (the Faraday effect). Parametric and cryogenically cooled receiver front end technology has been primarily driven by the needs of radio astronomy. The International Geophysical Year (IGY), launching (literally) a coordinated multinational effort to more fully understand the upper atmosphere's effects on communications, began the same year this story appeared in Radio-Electronics magazine. While it is true that radio astronomy has the advantage of not needing to wait for clear, dark skies to be useful the way observation in visible wavelengths...

ARRL Employment Opportunities

ARRL Employment Opportunities - RF Cafe"ARRL is seeking candidates for job opportunities at its headquarters in Newington, Connecticut. Available positions include Director of Information Technology, Public Relations & Outreach Manager, Social Media Strategist, and others. ARRL Human Resources Manager Luci Goodwin explained that some of the jobs are brand-new positions, established to help advance the association's ongoing digital transformation across membership programs, services, and publishing. 'Some of the positions are responsible for increasing awareness and growth of amateur radio,' said Goodwin. 'A new program area will expand ARRL's visibility in promoting ham radio to the public and through our outreach to like-minded communities.' A list of open positions, including the responsibilities and qualifications for each job, is posted on the ARRL Careers webpage. Employment opportunities are available for candidates with or without an amateur radio license..."

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...

Many Thanks to ConductRF for Continued Support!

ConductRF coaxial cables & connectors - RF CafeConductRF is continually innovating and developing new and improved solutions for RF Interconnect needs. See the latest TESTeCON RF Test Cables for labs. ConductRF makes production and test coax cable assemblies for amplitude and phased matched VNA applications as well as standard & precision RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the iBwave component library. They also provide custom coax solutions for applications where some standard just won't do. A partnership with Newark assures fast, reliable access. Please visit ConductRF today to see how they can help your project! 

Monday the 11th

Loudspeaker Crossover Design

Loudspeaker Crossover Design, July 1952 Radio-Electronics - RF CafeMany moons ago while in the USAF, I designed and built a pair of speaker enclosures out of pine wood in the base woodshop. Each had a separate bass, midrange, and tweeter speaker - all bought at the downtown Radio Shack (and the acoustically transparent cloth for the front). An issue of Popular Mechanics magazine had guidelines for the cabinet layout and made passing mention of the need to install an adequate frequency crossover unit in order to obtain the best performance. That article did not contain any information for designing your own crossover network, so I went about trying to figure out my own, based on a fairly limited knowledge of circuit theory and how to match impedances. There was no Internet back then for conveniently looking up that sort of stuff. I came up with a circuit that managed to work, but I honestly have no idea whether the frequency division was anywhere near what I thought it should be. I probably would have done just as well (or better) to have bought a high quality 3-speaker unit sold for car hi-fi stereos, and mounted them in the cabinets...

Robert W. Lucky, RIP

Robert W. Lucky, RIP - RF CafeIt was with sadness that I read on the IEEE Spectrum website of Robert "Bob" Lucky's passing March 10th this year. Born on January 9th, 1936, Mr. Lucky built an amazing legacy for himself through a combination of smarts, ambition, personality, and intuitiveness. He had a PhD from Purdue (aka "Parvoo" by Carl and Jerry), and spent many years at Bell Labs as a communications engineer. Back when I could afford an IEEE membership, I looked forward to reading his "Reflections" column, which always mixed serious analysis with a great sense humor and irony. His c1993 book, "Lucky Strikes ... again," is still a good read. Peruse through the sample pages on Amazon at the link above to get a flavor of Lucky's charm. Say, I just made a funny (the cereal, get it?), but that is easy to do with his name. Consider the book title, which has to be a play on the popular (at the time) cigarette brand "Lucky Strike." RIP, Bob Lucky, and thanks for the laughs.

Nuclear Bomb Effects Computer

Nuclear Bomb Effects Computer - RF CafeThanks to Ken H. for sending photos of his Nuclear Bomb Effects Computer (likely the original 1957 version). Both the computer and sleeve have EG&G's name printed on it. "This Nuclear Bomb Effects Computer has been compiled in cooperation with the Atomic Energy Commission, Division of Biology and Medicine, and Lovelace Foundation for Civil Effects Test Operations AEC-Biology And Medicine Contract AT(29-1)1242." Quickly and handily calculates Max. Fireball Radius, Height for Minimal Fallout, Apparent Crater Radius and Depth, and even Radiation Levels with 1st, 2nd, and 3rd degree burns! Who wouldn't have wanted one of these back in the 1960s while hunkering down in an underground bunker or beneath your school desk while thermonuclear ordinance was exploding overhead?

Determining Meter Shunts and Multipliers

Determining Meter Shunts and Multipliers, May 1931 Radio-Craft - RF CafeMost digital and analog multimeters rely on precision resistors for scaling the input voltage or current to keep it within the safe operational range of the meter movement or analog-to-digital converter circuit. Resistance value selection is a relatively simple matter of series and/or parallel combinations and their resulting divisions of voltages and/or currents. When this article appeared in a 1931 issue of Radio-Craft magazine, the whole concept of electrical circuit design was entirely new to most people, including shunts and multipliers for meter scales. The International Rectifier Company (IRC) article gives a handy rule of thumb for setting resistor values when considering the resistance of the meter movement coil. There is a nice table of resistor values provided, but I was a little disappointed to find that not a single equation is given for calculating custom values...

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...

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.

Sunday the 10th

Microwaves Themed Crossword Puzzle for April 10th

Microwaves Themed Crossword Puzzle for April 10th, 2022 - RF CafeHere is your custom made Microwaves-themed crossword puzzle for April 10th, 2022. 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 or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

Promote Your Company on RF Cafe for as Little as $40/Month

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 12,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. I also re-broadcast homepage items on LinkedIn. If you need your company news to be seen, RF Cafe is the place to be.

Thanks Once Again to everythingRF for Long-Time Support!

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

Friday the 8th

Magnetic Recording

Magnetic Recording, December 1947 Radio-Craft - RF CafeIn most instances the method and materials have changed over the years, but fundamental principles of writing and reading data to and from magnetic media are the same today as when this article was written in 1947. If you find that your lexicon of technical jargon lacks terms such as coercivity and remanence, then you might want to invest a few moments reading this short article that appeared in Radio-Craft magazine. I realize most regular RF Cafe visitors won't be interested, but hopefully someone, somewhere, searching for this information will now be able to find it. Thanks for your indulgence. Part I, "A Modern View of Permanent Magnet Theory," appeared in the October 1947 issue and Part II, "Benefits of Tape Recording," appeared in the November 1947 issue...

More on Balloon-Supported Antennas

More on Balloon-Supported Antennas, November 1940 QST - RF CafeKite- and balloon-lifted antennas are very popular in the amateur radio realm. They are primarily used for short-term activity such as during a contest or during an emergency; however, some operators use them on a more extended basis. A really good series of articles on the use of balloons and kites for suspending antennas can be found at qsl.net/g4vgo/antenna1.htm. Equations for calculating necessary balloon and kite sizes and predicting wind effects are included along with lists of 'Dos' and 'Don'ts.' This is not a new phenomenon. A 1940 edition of QST magazine described how to employ weather and sounding balloons to provide needed antenna configurations in places where suitable permanent structures were not available. Those balloons were intended to support antennas for extended periods of time - measured in weeks rather than hours. Here is a Short-Wave Craft article titled "Balloons Raise Shortwave Antenna..."

Transparent Antenna for 5G mmWave FWA

Transparent Antenna for 5G mmWave FWA - RF Cafe"The embrace of millimetre wave by the 5G era was celebrated as opening up vast new swathes of spectrum real estate that would enable hitherto unimaginable wireless data rates. There was just one problem, however - the propagation characteristics. While traditional low-frequency radio waves penetrate walls and windows as if they weren't there, the higher you go, the less effective spectrum is at this. That's one of the reasons the main use-case for mmWave so far has been fixed wireless access, because you can just create a point to point, line of sight, fixed setup, much like the microwave communications between cellular base stations. But in this scenario the customer premises equipment (CPE) still needs to be on the outside of the building, for the aforementioned propagation reasons. Glass, as you would expect, is easier for electromagnetic radiation to penetrate than brick, but how much easier depends on the glass, it seems. In these eco-conscious times the trend is towards low-emissivity (low-E) glass, which has superior insulating properties. The problem is that works both ways and double-glazing..."

Cardboard Engineering & Science Slide Rule Calculators

Cardboard Engineering & Science Slide Rule Calculators - RF CafeLong before there were smartphones and software "apps," engineers and scientists carried around portable "apps" of another kind. These apps were made from printed heavy cardboard stock and typically had either a sliding section sandwiched between two outer layers, or a rotating layer on a fixed base layer. They even sported rivets to hold them together - like the original Levis dungarees. I and guys much older than me [ ;-) ] routinely carried them in our shirt pockets, securely snugged behind our plastic pocket protectors. You definitely always wrote your name on them in indelible ink since there was a tendency for those cardboard slide rules to sprout legs and walk away while you were at lunch or in the can. These cardboard slide rule calculators used to be included on the Traditional Slide Rules page, but thanks to generous RF Cafe visitors who either sent me hard copies or high-res photos, the number has grown so large that they required their own page. You are invited to submit examples of your own collection for inclusion in the informal Cardboard Calculator Museum...

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...

Please Visit Triad RF Systems to Thank Them for Their Support

Triad RF SystemsTriad RF Systems designs and manufactures RF power amplifiers and systems. Triad RF Systems comprises three partners (hence 'Triad') with over 40 years of accumulated knowledge of what is required to design, manufacture, market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA, bi-directional, and frequency translating amplifiers are available, in formats including tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology partner than a vendor for our line-of-sight communications product line." Please check to see how they can help your project.

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