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Homepage Archive - April 2022 (page 3)

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

Thursday the 21st

Shell "Greenhouses" for the Boys "Upstairs"

Shell "Greenhouses" for the Boys "Upstairs", March 23, 1942 Life - RF CafeIn the run-up to World War II and during the battle, a lot of plastics research and production was considered classified defense information. Poly(methyl methacrylate) (PMMA), also know by the trade names of Plexiglas, Lucite, Crystallite, and others, was a crucial component for aircraft where the weight and brittleness of regular glass made it practically useless (and dangerous). A full-page ad by Shell Oil in this 1942 issue of Life magazine promoted plastic used in a bomber. When I see this, it reminds me of "It's a Wonderful Life," where Sam Wainwright offers George Bailey a position in his fledgling soybean-based plastic canopy factory in Buffalo, New York. Being primarily a petroleum product, plastic was promoted heavily by oil companies like Shell Oil, Standard Oil, American Oil, partially due to patriotism, but no doubt also for the profits. Those places, of course, were part of the "Military-Industrial Complex" identified by President Dwight Eisenhower. In fact, an Internet search turns up many claims that those same companies conspired to sell oil to Axis powers prior to America's official entry into WWII on December 7, 1941, when the Japanese bombed Pearl Harbor...

R&S Outdoor Spectrum Monitoring and Radiolocation

Rohde & Schwarz Launches Outdoor Spectrum Monitoring and Radiolocation Solution - RF CafeRohde & Schwarz announces the launch of the R&S UMS400 universal monitoring system for spectrum monitoring and radiolocation of frequencies from 8 kHz to 8 GHz (extendable up to 20 GHz with the R&S CS-MC20 microwave converter). R&S UMS400 meets 8 GHz (optionally 20 GHz) monitoring station needs in the ever-increasing frequency ranges demanded by wireless communications services. Before this latest Rohde & Schwarz innovation, monitoring such a range meant the monitoring sensor had to be placed as close as possible to the antenna for minimal cable losses and maximum sensitivity. R&S UMS400 has a compact outdoor housing and low power consumption that makes it ideal for temporary missions, such as event monitoring and radiolocation of sporadic interferers. It allows a wide range of use cases, including fixed and mobile spectrum monitoring, radiolocation of sporadic interference sources or short radio messages...

Let's Use Neon Bulbs 

Let's Use Neon Bulbs, July 1953 QST - RF CafeNeon bulbs used to show up in lots of commercial, military, and consumer products, but have given way to LEDs because of efficiency in cost, size, weight, and reliability. The 1950s-vintage radar I worked on in the USAF used lots of them as indicators. Before the availability of Zener diodes, they were used quite often as constant voltage references because of their characteristic of maintaining a fairly steady voltage value over a wide range of currents. One of the more useful tasks remaining for neon bulbs is for troubleshooting RF circuits because of their ability to glow in the presence of a strong electromagnetic field while only having physical contact with a single point in the circuit, or if the field strength and frequency is accommodating, without any physical contact at all. Some Ham radio operators still hang neon bulbs up on antenna masts where the feed line interfaces to the antenna to use while adjusting impedance matching circuits for maximum power transfer...

Preparing Engineering Students for Jobs

How to Prepare Students for the Manufacturing and Engineering Jobs of Tomorrow - RF CafeAutoDesk, the AutoCAD people, are offering a free whitepaper entitled: "How to Prepare Students for the Manufacturing and Engineering Jobs of Tomorrow." Technology used in manufacturing and engineering is changing so quickly that industry is having a hard time finding workers with the necessary skill sets. In fact, new research shows that 30% of workers with mid-level skills will be obsolete by 2030. How can you help your students succeed in an environment where employer needs are constantly changing? Get the latest findings and put them into practice now. This new report on Industry 4.0 reflects leading-edge research - and provides informed, actionable recommendations. This report is your roadmap to a successful future for you and your students. Download your free copy...

$5.00 for Best Short Wave Kink

$5.00 for Best Short Wave Kink, August 1935 Short Wave Craft - RF CafeYou might not have the need for a variable capacitor made from a match box and a couple strips of tin foil, but there are plenty of other "shortwave kinks" offered here that could be of use to you when the preferred part is not available. For instance, maybe a transformer exhibits an audible hum because of improper construction, or maybe a vernier dial is needed for an adjustment knob; homebrew solutions are offered for both. The adjustable capacitor idea is an "outside-and-inside-the-box" solution (pun intended) that could come in handy. In all, there are 11 tips from way back in 1935 offered by fellow radio enthusiasts, and printed in Short Wave Craft magazine...

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

Engineering Job Board - RF CafeRF Cafe's raison d'être is and always has been to provide useful, quality content for engineers, technicians, engineering managers, students, and hobbyists. Part of that mission is offering to post applicable job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge. 3rd party recruiters and temp agencies are not included so as to assure a high quality of listings. Please read through the easy procedure to benefit from RF Cafe's high quality visitors...

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.

Wednesday the 20th

Television... It's a Cinch

Television... It's a Cinch, July 1955 Radio-Electronics - RF CafeE. Aisberg wrote a series of columns for Radio-Electronics magazine in the middle 1950s titled "Television... It's a Cinch," informing the reading public about television in general and the newly emerging color TV more specifically. He chose to use a unique dialog format where two people were in a back-and-forth discussion about the technology. This July installment is the first half of the seventeenth conversation. Antennas, tuned circuits, component reliability, transmission lines, installation, and many other aspects of successful television viewing are covered. The series began with the February 1953 issue, and ran through October 1955. I will post the others as time permits...

Thanks to Anritsu for Their Support!

Anritsu (electronics test equipment)Anritsu has been a global provider of innovative communications test and measurement solutions for more than 120 years. Anritsu manufactures a full line of innovative components and accessories for RF and Microwave Test and Measurement Equipment including attenuators & terminations; coaxial cables, connectors & adapters; o-scopes; power meters & sensors; signal generators; antenna, signal, spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth & WLAN testers; PIM testers; amplifiers; power dividers; antennas.

Magnolia Radio Lab Advertisement

Magnolia Radio Lab Advertisement, May 1941 QST - RF CafeA regular feature in the ARRL's magazine QST during the early days of radio was "New Receiving Tubes." It usually had your standard editorial listing of products, but the May 1941 installment included a comic commissioned my the Magnolia Radio Lab people that is done in the manner of Ripley's Believe It or Not. I'm guessing that there really is no Magnolia Radio Lab because nothing came up on a fairly extensive Internet search for the company. Most good humor has an element of truth in it that makes the subject matter believable - almost. These three comics meet that criterion. "Gil - W1CJD" (aka Philip "Gil" Gildersleeve) was the artist...

Modelithics Releases COMPLETE Library v22.1 for Keysight ADS

Modelithics® Releases COMPLETE Library™ v22.1 for Keysight ADS - RF CafeModelithics is pleased to announce the release of the latest version, v22.1, of the Modelithics COMPLETE Library for use with Keysight Technologies' PathWave Advanced Design System (ADS). This version adds a total of 26 new models for various components to the Modelithics COMPLETE Library. With these new additions, the Modelithics COMPLETE Library now includes over 825 models that represent over 25,000 passive and active RF/microwave components. This collection of simulation models comprises surface-mount RLC components, diodes, transistors, amplifiers, attenuators, filters, couplers, and other components. Version 22.1 adds new scalable Microwave Global Models™ to the Modelithics COMPLETE Library, including models for the 0201HL inductor series from Coilcraft, the 08051C capacitor series from Kyocera-AVX, and the CBR04 and CBR06 automotive series from KEMET...

Report on the European Radio Industry

Report on the European Radio Industry, May 1946 Radio News - RF CafeBy 1946, radio and television manufacturers were scurrying to supply the huge, pent-up demand for communications and entertainment systems that accumulated during World War II. Fortunately, the dearth of electronics components, raw materials for chassis fabrication, and available labor was suddenly and significantly turned around by late 1945. Wanton destruction of entire cities in Europe left citizens without many basic creature comfort items like radios, televisions, refrigerators, vacuum cleaners, toasters, automobiles, and other things taken for granted a decade earlier. As with any well-executed plan, manufacturers endeavored to survey the market demand for such products and then devised a way to satisfy that demand. Radio News magazine published a synopsis in mid-1946 of the state of the radio and television industry in Europe so that companies...

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 Exodus Advanced Communications for Their Support

Exodus Advanced Communications - RF CafeExodus Advanced Communications is a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide. Power amplifiers ranging from 10 kHz to 51 GHz with various output power levels and noise figure ranges, we fully support custom designs and manufacturing requirements for both small and large volume levels. decades of combined experience in the RF field for numerous applications including military jamming, communications, radar, EMI/EMC and various commercial projects with all designing and manufacturing of our HPA, MPA, and LNA products in-house.

Tuesday the 19th

Radio Terms Illustrated

Electronics-Themed Comics, November 1946 Radio-Craft - RF CafeHere are a couple more of the much-liked "Radio Term Illustrated" comics, these appearing in the May 1947 issue of Radio-Craft magazine. I probably spend way more time on colorizing these comics than I should. You might think it's easy to just fill in areas with color, but most of the comics are drawn in a manner where outlines of larger objects do not terminate against another line. Being able to use a fill tool requires sealing off the area first. Then there's the case of where an area uses a series of closely spaced lines or cross-hatches. An area fill tool doesn't work well there, either, so the best way I've found is to outline the area with a Bezier curve tool and copy / paste it over itself so it is a separate object, then use a color transform tool to shift the entire area to the chosen color. Even with all that work, the comics rarely turn out the way I'd like them to...

Next-Gen ePaper Delivers Richer Colors

Next-Gen ePaper Delivers Richer Colors - RF CafeThese reports on advances in ePaper technology remind me of the 1990s as color computer monitors were ratcheting up pixel and color count - first with CRTs and then LCD and LED flat panel displays. ePaper is a purely reflective vs. back-lit display. "E Ink's digital paper, often called ePaper, has found a home in e-readers, displays, and even covering cars. Balancing the need for high-quality displays and power requirements has always been a challenge. It started as a gray scale display, but color ePaper displays have been available for a while. The latest generation, E Ink's Kaleido 3, takes the quality to a new level. It can deliver 16 levels of gray scale and 4,096 colors. This new display increases color saturation by 30% compared to the earlier Kaleido Plus. It can display animations and videos. The Kaleido 3 employs a color filter array (CFA) that's used in conjunction with E Ink's Carta black-and-white ink film. The display also uses the company's ComfortGaze, a front-light technology designed by E Ink's Front Light Team. The technology reduces the amount of blue light reflected off the surface of the display and lowers the blue light ratio (BLR) by 60% and blue light toxicity factor (BLTF) by 24%..."

Carl & Jerry: Eeeeelectricity!

Carl & Jerry: Eeeeelectricity!, November 1956 Popular Electronics - RF CafeWikipedia claims there are about 350 species of electric fish. Jerry tells fellow electrical and electronics experimenter Carl that the electric eel is not an eel at all, but a fish. Actually, the eel is a fish (a knifefish); however - and I needed to look this up - a true eel is a member of the fish order Anguilliformes, which the electric eel is not. Having no expertise in the field of eels, I'll leave it at that. Jerry's uncle, who is an active duty Navy guy, somehow managed to ship an electric eel to him for experimentation purposes. Doing so might have been possible in 1956 when this episode of "Carl & Jerry" appeared in Popular Electronics magazine, but today it is doubtful. Besides that, how to you mail an electric eel to somebody? The pair's measurements of voltages and pulse widths jive pretty well with modern data. Here is a story about how electric eels curl to obtain higher voltages for stunning prey...

The XML Guts of an Excel Workbook File

The XML Guts of an Excel Workbook File - RF Cafe SmorgasbordSome years ago while first developing my "RF Cascade Workbook" spreadsheets, I read that when Microsoft began using the XML file format for Excel with the 2007 version (Office 12), what appears in the File Manager as a *.xls or *.xlsm (*.xls with VBA‡ macros) is actually a compressed collection of individual XML files and possibly a *.bin and any images you might have buried within. If you want to see what actually makes up your Excel file, follow these simple instructions. A word of warning though, as Otto von Bismarck is reported to have admonished†, "Laws are like sausages. It is better not to see them being made." After seeing what goes into an Excel file, you might loose your taste for them (not really, it just seemed like an apt quotation at the moment). There may be another way to dissect an Excel file, but probably the easiest is the following...

Arvin Models 152T, 153T Schematic & Parts List

Arvin Models 152T, 153T Schematic & Parts List, July 1948 Radio News - RF CafeThis "Radio Service Data Sheet" from a 1948 issue of Radio News provides schematics and parts lists for Arvin Models 152T and 153T receivers. Most - if not all - electronics servicemen had subscriptions to these magazines because they were a ready source of not just these service sheets, but because of the extensive articles offering advice on servicing radios and televisions. In fact, many electronics manufacturers had a policy of supplying service data only to bona fide shops. A large list is included at the bottom of the page of similar documents from vintage receiver schematics, troubleshooting tips, and alignment procedures. They were originally published in magazines like Radio-Craft, Radio and Television News, Radio News, etc. I scan and post them for the benefit of hobbyists who restore and service vintage electronics equipment...

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 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.

Monday the 18th

Radar Tames the Wild Blue Yonder

Radar Tames the Wild Blue Yonder, November 1956 Popular Electronics - RF CafeThe VOLSCAN (Volume Scanning) radar system was a paradigm changer for air traffic controllers charges with guiding aircraft while assuring safe separation. Busy terminal areas were a particularly difficult challenge due to the large variation in aircraft speeds and types. VOLSCAN was a computer that tracked the position, direction, and speed of each target and even made recommendations to controllers for course assignments. It also warned of impending dangerous scenarios. Another VOLSCAN article in the July 1954 issue of Radio-Electronics magazine went into more detail and had color photos of the equipment. Interestingly, the equivalent of maybe the world's first light pen computer interface is used by the operator for letting the processor know what part of the screen (PPI, or plan position indicator) he is referring to...

Eyes of a Generation™... Television's Living History

Eyes of a Generation™... Television's Living History - RF Cafe SmorgasbordIf ever there was a website that would likely drag a radio and television broadcast historian down into the metaphorical rabbit hole, "Eyes of a Generation... Television's Living History" is it. Like Alice's experience in Wonderland, once you enter the homepage porthole and begin clicking on links, not only will getting back out be difficult, but the journey will introduce you to many fantastic experiences in TV broadcasting which you have never seen before. As the subtitle says, "In essence, this is a Television history book with 5000 stories, 10,000 rare photos and hundreds of one of a kind videos." If you are old enough to remember way back to the 1980s and before, then you will find interesting tidbits of insider and backstage anecdotes about all of the popular television shows of the various eras - back to the very beginning. That includes sitcom, variety, and news types. Included in the collection is a wealth of photographs and videos, along with histories of the electronic equipment and its inventors that made it all possible. You will also find never-seen-before film footage of live taping sessions, TV show production, interviews, and documentaries. Did you know that David Letterman owned the entire "Late Night" franchise...

"Printed Wiring" Techniques for the Experimenter

"Printed Wiring" Techniques for the Experimenter, August 1956 Popular Electronics - RF CafeIn part one of a two-part article, Popular Electronics magazine presents some of the inner workings of what at the time was a fledgling industry - printed circuit board manufacturing. In 1956, when this piece appeared, a large percentage of electronics assemblies were still being wired in a point-to-point manner where resistors, capacitors, inductors, tubes, and cables were soldered directly to terminals either on special blocks or on tube sockets. The process was heavily labor intensive and prone to miswirings. High volume production was nearly impossible prior to printed wiring boards (PWBs). Bell Telephone Labs was an early adopter and driver of the technology. A good example of an early telephone PWB can be seen in the 1970s vintage Snoopy telephone that I reconditioned a while back. Note the rat's nest of wires going to the network terminal block...

Lithium Niobate Laser Chip for High-Powered Telecoms

Lithium Niobate Laser Chip for High-Powered Telecoms - RF Cafe"For all the recent advances in integrated lithium niobate photonic circuits - from frequency combs to frequency converters and modulators - one big component has remained frustratingly difficult to integrate: lasers. Long haul telecommunication networks, data center optical interconnects, and microwave photonic systems all rely on lasers to generate an optical carrier used in data transmission. In most cases, lasers are stand-alone devices, external to the modulators, making the whole system more expensive and less stable and scalable. Now, researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) in collaboration with industry partners at Freedom Photonics and HyperLight Corporation, have developed the first fully integrated high-power laser on a lithium niobate chip, paving the way for high-powered telecommunication systems, fully integrated spectrometers..."

International Kadette Model 66 and 666 Radio Service Data Sheet

International Model 66 and 666, 6-Tube Superhet Radio Service Data Sheet - RF CafeThis "Radio Service Data Sheet" covers the International Kadette Model 66 and 666, superheterodyne receiver. Most - if not all - electronics servicemen had subscriptions to these magazines because they were a ready source of not just these service sheets, but because of the extensive articles offering advice on servicing radios and televisions. In fact, many electronics manufacturers had a policy of supplying service data only to bona fide shops. A large list is included at the bottom of the page of similar documents from vintage receiver schematics, troubleshooting tips, and alignment procedures. They were originally published in magazines like Radio-Craft (this April 1936 issue), Radio and Television News, Radio News, etc. I scan and post them for the benefit of hobbyists who restore and service vintage electronics equipment...

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 PCB Directory for Continued Support!

PCB  Directory - RF CafePCB Directory is the largest directory of Printed Circuit Board (PCB) Manufacturers, Assembly houses, and Design Services on the Internet. We have listed the leading printed circuit board manufacturers around the world and made them searchable by their capabilities - Number of laminates used, Board thicknesses supported, Number of layers supported, Types of substrates (FR-4, Rogers, flexible, rigid), Geographical location (U.S., China), kinds of services (manufacturing, fabrication, assembly, prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.

Sunday the 17th

Technology Themed Crossword Puzzle for April 17th

Technology Themed Crossword Puzzle for April 17th, 2022 - RF CafeHere is your custom made Technology-themed crossword puzzle for April 17th, 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.

Please Visit Empower RF's Website in Appreciation of Their Support

Empower RF Systems - RF CafeEmpower RF Systems is a global leader in power amplifier solutions. Empower RF Systems is an established and technologically superior supplier of high power solid state RF & microwave amplifiers. Our offerings include modules, intelligent rack-mount amplifiers, and multi-function RF Power Amplifier solutions to 6 GHz in broadband and band specific designs. Output power combinations range from tens of watts to multi-kilowatts. Unprecedented size, weight and power reduction of our amplifiers is superior to anything in the market at similar frequencies and power levels.

Friday the 15th

The Future of the Transistor

The Future of the Transistor, July 1952 Radio-Electronics - RF CafeFor many years, Radio-Electronics magazine editor Hugo Gernsback and Audion tube inventor Dr. Lee de Forest had sort of a mutual admiration society thing going on. that's understandable because they we both men of great accomplishment and are deserving of everyone's admiration. In this 1952 issue, Dr. de Forest was invited to procrastinate on future of the transistor - the semiconductor equivalent of his amplifying vacuum tube. He humbly states, "If in the year 1912 some editor had requested of me an article on the 'Future of the Electronic Tube,' I probably would have felt quite as incompetent and short-sighted a prophet of the developments of that [...], as I feel today as Mr. Gernsback requests from me an outlook over the future of the transistor, [the] possible successor of the grid tube." Less than four yeas had passed since the Bell Labs trio announced their transistor invention, but the technology advanced quickly once made known. History shows Dr. de Forest was correct in predicting the vacuum tube and transistor (in all their various forms) would coexist for a long time. It was not until the 1980s that solid state devices had replaced nearly all tubes (except the CRT display)...For many years, Radio-Electronics magazine editor Hugo Gernsback and Audion tube inventor Dr. Lee de Forest had sort of a mutual admiration society thing going on. that's understandable because they we both men of great accomplishment and are deserving of everyone's admiration...

I Married a Superheterodyne!

I Married a Superheterodyne!, February 1956 Popular Electronics - RF CafeBased on beleaguered wife Sylvia Kohler's mention of GE's Electronics Park in this story (surely a fable... or not), she and unintentional antagonist, superheterodyne hubby (aka "Happy Boy," but we know him as Popular Electronics cartoonist Carl Kohler) probably lived in the Syracuse, New York, area. Electronics Park (technically in Liverpool/Salina) existed during the hey days of General Electric when the sprawling campus , just north of I-90, designed and manufactured a plethora of both household (TVs and radios) and military electronics products. GE's Electronics Laboratory ("E-Labs") was the company's pride and joy. Today, a tiny portion of Electronics Park is still occupied by Lockheed Martin, who bought that GE division in the 1990s, and the rest belongs the city. I worked there for about two years. But I digress... enjoy the story (I highlighted her reason for referring to hubby as a Superheterodyne)...

Reactel Waveguide Filter Video

Reactel Waveguide Filter Video - RF CafeReactel, industry leaders in the design and manufacture of RF and Microwave filters, diplexers, and sub-assemblies from DC to 67 GHz, recently produced a new video short on Waveguide Filters. Benefits of waveguide filters include very low insertion loss, extremely narrow bandwidths, high power handling, and very sharp band edge rolloff. Custom sizes and shapes are available, along with many variations on duplexers, diplexers, multiplexers, switched filter banks, and other configurations. Many off-the-shelf products are available, and Reactel engineers are happy to assist you with determining your system's needs and designing filters to help you succeed. Please take a couple minutes to view this video, then give Reactel a call.

"Back on the Air" Musical Tribute to Ham Radio

"Back on the Air" - Musical Tribute to Ham Radio - RF CafeThe "Up Front" page of the May 2022 issue of QST magazine mentions a musical tribute to ham radio entitled, "Back on the Air," by Allen Chance (W2BUZ) and Paul Rogers. It has a soothing melody and the video is accompanied by photos matching the lyrics as it goes along. You probably have to be a Ham operator to appreciate the message and visuals. A repeating CW CW CW in Morse code can be heard in the background. Warning: If you are easily triggered by a couple "guy" pictures, this video is not for you; please move on...

Multi-Impedance Dipole Antennas

Multi-Impedance Dipole Antennas, May 1953 QST - RF CafeMaybe I suffer from cranial rectumitis at the moment, but I'm having a hard time with a statement made in this 1953 issue of QST magazine about coaxial feedline impedance, to wit, "102-ohm line (52-ohm lines in series)." I must be missing something because I don't understand how placing two 52-ohm transmission cables in series results in twice the impedance. Aside from that, author John Avery presents an interesting article on multi-impedance dipole antennas. Empirical data is presented on how the feed−point impedance of a dipole varies with distance above the ground. His results are very close to theoretical values which assumes non-sagging elements, perfectly linear alignment, a perfectly conductive ground, etc. He then extended his investigation into 2-wire (4x impedance) and 3-wire (9x impedance) folded dipole antennas...

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 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. 

   

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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RF Cascade Workbook 2018 - RF Cafe
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About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024

Webmaster:

    Kirt Blattenberger,

    BSEE - KB3UON

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...

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