Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives RF Cascade Workbook 2018 RF Symbols for Visio - Word Advertising RF Cafe Forums Magazine Sponsor RF Cafe RF Electronics Symbols for Visio RF Electronics Symbols for Office Word RF Electronics Stencils for Visio Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Anritsu Alliance Test Equipment Amplifier Solutions Anatech Electronics Axiom Test Equipment Berkeley Nucleonics Bittele Centric RF Conduct RF Copper Mountain Technologies Empower RF everything RF Exodus Advanced Communications Innovative Power Products ISOTEC KR Filters Lotus Systems PCB Directory Rigol RF Superstore San Francisco Circuits Reactel RFCT TotalTemp Technologies Triad RF Systems Windfreak Technologies Withwave LadyBug Technologies Wireless Telecom Group Sponsorship Rates RF Cafe Software Resources Vintage Magazines Thank you for visiting RF Cafe!
RF Cascade Workbook 2018 - RF Cafe

Homepage Archive - September 2022 (page 4)

See Page 1 | 2 | 3 | 4 of the September 2022 homepage archives.
col-width

Friday the 30th

Thursday the 29th

Wednesday the 28th

Tuesday the 27th

Why No "Postwar" Radios?

Why No "Postwar" Radios?, August 1946 Radio-Craft - RF CafeThis is one of the few times I disagree with Hugo Gernsback. It's not that his conclusion about economics being the reason for the delay in producing promised newfangled radios after the end of World War II is wrong. My problem is that he excuses the manufacturers who blamed delays on the large amount of time and effort required to incorporate all the new technology developed during the war. As Radio-Craft magazine reader C.G. Little wrote in this August 1946 issue, companies were running advertisements a year before V−E Day (May 8, 1945) promising to have all-new radios with wonderful new technology developed from advances made in radio and radar during the defeat of Axis forces. Japan surrendered on V−J Day (September 2, 1945). The fact is those companies had a year to prepare, and the U.S. government was gradually relinquishing control over production facilities as the War Powers Act impositions faded. Nobody was taken by surprise. This was either a case of government-backed propaganda, or false advertising by the manufacturers...

Overnight Charging of EV's Bad for High Density Areas

 - RF CafeAn Electronics Weekly article entitled "Modelling Grid Effects of Electric Vehicle Charging in the Next Decade" references Nature magazine study "Charging Infrastructure Access and Operation to Reduce the Grid Impacts of Deep Electric Vehicle Adoption," which indicated high density areas with currently (no pun intended) stresses electric supply grids will be problematic. It is a Captain Obvious announcement to anyone following the existing issues like a couple weeks ago California telling EV owners not to charge their cars because of the power shortage. It begins: "Researchers at Stanford University have modelled over-night home charging of electric vehicles and predict that it is not the correct strategy, for the Western US, at least. Stanford EV charging model Simulation is based on a model, revealed in March, for charging demand that can be applied to different human populations under different conditions. In a demonstration..."

RCA Victor Model R-78 Radio Service Data Sheet

RCA Victor Model R-78 B1-Acoustic 12-Tube Superheterodyne Radio Service Data Sheet, August 1932 Radio-Craft - RF CafeFor several years I have been scanning and posting Radio Service Data Sheets like this one featuring the RCA Victor Model R-78 B1-Acoustic 12-Tube Superheterodyne floor console radio in graphical format, and run OCR on them to separate the textual content and make it searchable. There are still many people who restore and service these vintage radios, and often it can be difficult or impossible to find schematics and/or tuning information. I will keep a running list of all data sheets to facilitate a search. The RCA Victor Model R-78 B1-Acoustic 12-Tube photo was found on the RadioMuseum.org website...

SATCOM SDR-Enhanced Phased-Array Antennas

Strengthen SATCOM with SDR-Enhanced Phased-Array Antennas - RF CafeBrendon McHugh has an interesting article on the Microwaves & RF website entitled, "Strengthen SATCOM with SDR-Enhanced Phased-Array Antennas." It begins: "Many SATCOM apps require constant communication between the satellite and ground station, which can be difficult with conventional antennas. Phased-array technologies, coupled with SDRs, provide the robust comm link necessary for proper operation. Satellite communication (SATCOM) is one of the pillars of the modern world, with applications including Global Positioning System (GPS) and Global Navigation Satellite System (GNSS) navigation, space research, telecommunications, internet access, weather monitoring, and law-enforcement surveillance. Together with the satellite itself, ground stations are crucial to the SATCOM industry. They transmit and receive data to and from the satellite, process the information, and apply it to different purposes, depending on the application. Therefore, it’s fundamental to ensure an efficient, reliable, and robust..."

Simple Radio Mathematics for the Service Man

Simple Radio Mathematics for the Service Man, September 1930 Radio-Craft - RF Cafe Included in this first of a series of the "Simple Mathematics for the Serviceman" articles that ran in Radio-Craft magazine is another "cheat sheet" full of oft-used formulas. It begins with basic Ohm's law, resistance, inductance, and capacitance, then builds from there. What was valid in 1930 is still valid in 2022. See the October 1930 issue for the next installment that includes yet another handy-dandy cheat sheet of formulas. A couple examples are given...

Promote Your Company on RF Cafe

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 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.

Monday the 26th

Ceramic Capacitors

Ceramic Capacitors, July 1965 Electronics World - RF CafeI learned a new word in this issue of Electronics World magazine's special report on ceramic capacitors: "discoidal." It looked like a made-up word to describe something that looks like a disc. Anyway, the July 1965 issue contained a collection of articles on the various sorts of capacitors in use at the time. Other types of dielectrics covered were tantalum, glass, plastic-film, mica, paper, and metallized-dielectric. Ceramic and electrolytic capacitors were by far the most widely used capacitors during the vacuum tube era since they were relatively inexpensive to manufacture and could handle high voltages. Hobbyists who service and/or refurbish vintage electronic equipment still need this information if for no other reason than to verify component values based on color codes. It also helps to know how the electrical properties vary over temperature, frequency, applied voltage, etc., when deciding which type of modern capacitor will best serve as a suitable substitute...

Anatech Electronics September Newsletter

Anatech Electronics September 2022 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his August 2022 newsletter that features his short op−ed entitled "It's Official: DSRC is Dead," where he discusses how the 1999 era (Y2K era remember?) "Dedicated Short-Range Communications (DSRC)," which was allocated 75 MHz of spectrum at 5.9 GHz for "intelligent transportation systems," is no more. "Cellular to Everything (C-V2X)" is its replacement. Also reported is the introduction of C-Band-proof radar altimeters, a THz development grant to NYU's Tandon School of Engineering, and HawkEye 360 developing RF-sensing capabilities for U.S. Army. As always, Sam demonstrates a keen awareness of the industry for which his company, Anatech Electronics, services...

Admiral Model 7C63 Console Radio

Admiral Model 7C63, Chassis 7C1 Schematic & Parts List, December 1947 Radio News - RF CafeThere are still many old-timers and beginning nostalgic collectors out there who nurse heirloom and otherwise procured vacuum tube radios - like this Admiral Model 7C63, Chassis 7C1 - back to health (operating condition) and/or keep them in good health. The thumbnail to the left is an example from the RadioMuseum.org website. While it is possible to purchase schematics, parts lists, and service instructions from many different models, there are still some that have escaped the scanners of those publishers. For those kindred spirits in search of such reference materials, I happily scan, clean up as necessary, and post this collection (see complete list at bottom of page). I have dozens more that will eventually be added over time, so check back later or send me an e-mail if I have an issue (check the lists first, please) of Radio News, Radio-Craft, etc., known to contain the information you need...

"Dilbert" Cancelled in Newspapers Due to Anti-Wokeness Storylines

"Dilbert" Cancelled in Newspapers Due to Anti-Wokeness StorylinesAny day now we'll see a headline about a Stasi (aka FBI) raid on Scott Adams' home at 6:00 in the morning to confiscate his cellphone. Evidently it's not OK to poke fun at the "woke" agenda according to (as of now) 77 newspapers which cancelled the "Dilbert" comic strip. Many newspapers have gone out of business or are on the verge of doing so due to disappearing subscribers. People are sick of having one view forced at them with no counterpoints. I'm sure Adams makes plenty of $$$ from other Dilbert-related ventures, so he probably will not miss the revenue. A lot of people still subscribe to newspapers mainly for comics and puzzles. This will just add to the "go woke - go broke" phenomenon we're witnessing happening to politically correct businesses. Go to Dilbert.com for all your Dilbert needs.

Man Fined for Off-Frequency Operation 

Fined for Off-Frequency Operation, October 1931 QST - RF CafeSince its inception in 1934, the Federal Communications Commission's (FCC) Enforcement Bureau has taken seriously its charter to monitor and protect designated frequency bands against both intentional and unintentional interference. Except for malicious attacks on legitimate operations, most instances of interference are the result of utter ignorance or accidental broadcasting due to inattention to detail (wrong frequency dialed in) or equipment malfunction. Standard practice is to issue an immediate cease and desist order to the offending party, and then go forward with prosecution if compliance does not follow. News stories appear fairly often about pirate broadcasters and idiots exacting revenge on someone else who allegedly offended said idiot. The $500 fine levied on Mr. Winston in 1931 is the equivalent of a $9,938.62 fine in 2022 (see BLS Inflation Calculator). That is a lot of money, but it pales in comparison to the typical $25k and higher fines charged recently to habitually errant Hams. Evidently, his case fell under the intentional interference category...

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

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

Thanks 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.

Sunday the 25th

Electrical Engineering Crossword Puzzle for September 25th 

Electrical Engineering Theme Crossword Puzzle for September 25th, 2022 - RF CafeThis custom made Electrical Engineering theme crossword puzzle for September 25th is provided compliments of RF Cafe. It's a big one with more than 240 words - good for a long flight. 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 puzzle 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!

Get Your Custom-Designed RF Cafe Gear!

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

Thanks to Wireless Telecom Group for Their Support!

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

Friday the 23rd

Electronics-Themed Comics

Electronics-Themed Comics, March 1952 Radio-Electronics - RF CafeTGIF. Even with being self-employed, I still am always glad when Friday gets here. Aside from some morning work posting content for my AirplanesAndRockets.com hobby website, Saturday is my only day completely off from RFCafe.com business. Anyway, a good way to wind down the week is with some good old-fashioned humor. These couple electronics-themed comics from a 1959 issue of Radio-Electronics magazine are literally old-fashioned. The comic on page 52 is actually a tongue-in -cheek criticism aimed at the housewife who must have make a remark about how easy television servicing probably is. However, the technician's response is really not such a bad high-level check of the health of the vacuum tubes. Heater elements burning out was a fairly common cause of a tube being bad. Of course nobody would want to go through and feel all the tubes' temperatures because those suckers can get hot enough to burn...

The Day the U.S. TV Industry Died

The Day the U.S. TV Industry Died - RF CafeNote that while Zenith Electronics (now owned by LG) has only been around 40 years, Zenith has been manufacturing TVs in the U.S. since 1939. Per the IEEE Spectrum article - "Why the last major U.S. television set maker, Zenith, finally gave up. Driven finally into unprofitability in its traditional market by ever stiffer competition from abroad, harmed rather than helped by a decade of economizing cutbacks in research and development, Zenith Electronics Corp. - the sole surviving U.S. manufacturer of television receivers - reportedly plans to call it quits in the business it helped to create and nourish through some 40 years of innovation. Indeed, nothing so neatly reflects the company's present situation as its latest and arguably its second greatest innovation: a flat shadow mask for a flat-faced cathode ray tube hailed everywhere as a major breakthrough. Announced in 1986, the Flat Tension Mask, as it is called, increases the brightness of the cathode ray tube by up to 80%, its contrast ratio by up to 70%, and its resolution by up to 15% over current tube designs, which use a curved face plate and curved shadow mask..."

CMT's New R140B 1-Port VNA with Flexible Connector

Copper Mountain Technologies' R140B 1-Port VNA with Flexible Connector Configuration - RF CafeCopper Mountain technologies' new R140B 1-Port 14 GHz Analyzer is an enhanced version of its predecessor - the R140 reflectometer - featuring faster measurement speeds, wider IFBW, and an improved dynamic range. The R140B incorporates a new housing design similar to CMT's R60, taking advantage of enhanced heat exchange characteristics and a sturdy USB shroud. It will feature a new connector assembly, which includes four different port connector options (N male, female; 3.5 mm male, female). The new connector assembly enables flexible configuration while maintaining a small form factor suited for laboratory, field, or production environment applications. "With built-in differential measurement capabilities, this product will enhance the design and production of next-generation HDMI and USB cables for consumer goods and high bandwidth data...

2011 Chevy Camaro Convertible AM/FM Antenna

2011 Chevy Camaro Convertible AM/FM Antenna Solution - RF Cafe SmorgasbordI have often said that some of the most capable and enthusiastic engineers and technicians - and even managers - I have worked with in my 30-something year electronics career have been amateur radio operators. They are the rare few who are able to combine a hobby passion with a profession that pays for the hobby... kind of like the airline pilot who flies model airplanes or the druggie who works at a pharmacy. Oh, wait, scratch that last example. Here we see a video from Chevrolet where two engineers, one of them a Ham, took up the challenge to replace the AM/FM whip antenna originally planned for the 2011 Camaro convertible with a blended, inconspicuous antenna. Leaked photos of the prototype car showed the whip, which caused Camaro aficionados to descend upon Chevy requesting its removal. The flexible, folding rear window prevented an embedded solution as is the norm for many cars. The ultimate solution? Embed the antenna in the spoiler. Given the retro nature of the Camaro, the hew and cry against the whip antenna is a bit surprising. I had a '69 Camaro SS and a '74 Camaro SS, and of course both had whip antennas. Kirt Blattenberger (circa 1977) 1969 Camaro SS w/350 cu.in. LT−1 engine (Wikipedia says production began in 1970, but actually late 1969) Bracket Racing Trophy from Capitol Raceway According to the video, the two engineers spent 10 months rushing to get the antenna into the spoiler prior to rollout. So, how much did the change likely cost...

Quantic PMI September 2022 New Products

Quantic PMI September 2022 New Product Announcement - RF CafeQuantic PMI, a leading supplier of custom, high-reliability MIC/MMIC components and subsystems for applications in space, military, communications, commercial and consumer electronics systems for more than three decades, introduced six new products this month in their extensive line of RF and microwave components. Included are a bi-directional switched bit attenuator operating from 400 to 1400 MHz, an RF Limiter that operates over 1.0 to 2.0 GHz, a low noise amplifier with a frequency range of 8 to 12 GHz, a reflective, SP2T switch that operates over 2 to 18 GHz, a SP2T Reflective Pin Diode Switch with a frequency range of DC to 18.0 GHz. Contact Quantic PMI today for more information...

Echophone Radio w/Hogarth

Echophone Radio w/Hogarth, August 1945, Radio-Craft - RF CafeHogarth is a comic character invented by the Echophone Radio Company. Their bespectacled Army grunt was one of the first technology nerd types who always managed to appear with pretty girls. His caricature evolved quickly over the two or three year run of the advertisements. Most Echophone Radio ads I have seen either feature Hogarth and his woman/women or Hogarth and a demanding sergeant. This full-page advertisement appeared in the August 1945 edition of Radio-Craft magazine. A search on the name "Hogarth" does not give any clue as to the reason for choosing it. For what it's worth, here is the Ancestry.com data on Hogarth. Echophone radios can still be found on eBay for fairly low prices - often less than the shipping cost...

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 to LadyBug Technologies for Their Continued Support!

LadyBug Technologies RF Power Sensors - RF CafeLadyBug Technologies was founded in 2004 by two microwave engineers with a passion for quality microwave test instrumentation. Our employees offer many years experience in the design and manufacture of the worlds best vector network analyzers, spectrum analyzers, power meters and associated components. The management team has additional experience in optical power testing, military radar and a variety of programming environments including LabVIEW, VEE and other languages often used in programmatic systems. Extensive experience in a broad spectrum of demanding measurement applications. You can be assured that our Power Sensors are designed, built, tested and calibrated without compromise.

Thursday the 22nd

Kay−Townes Rear−Guard Antenna

Kay−Townes Rear−Guard Antenna, December 1954 Radio & , December 1954 Radio News - RF CafeCall me a skeptic, but somehow I doubt the accuracy of the "Radiation Curve Representing All VHF Channels" presented in this Rear-Guard antenna ad. It appeared in the December 1954 issue of Radio & Television News magazine. Truth in advertising laws were probably not as strictly enforced as they are today. The main lobe utterly dominates the response, with barely any power in the side and back lobes. Even a well-designed, narrow-band parabolic dish is fortunate to have such a near-perfect directional pattern. Aside from that, I wonder how many people today "get" the picture of the kid with a pillow strapped to his behind and understand the relationship to "Rear-Guard?" Back in the day, kids sometimes experienced marshal punishment in the form of a hand or a wooden paddle to the body area normally sat upon. It was known as a spanking. I know from personal experience that the threat of receiving such punishment often served as sufficient deterrence from committing certain naughty acts...

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! 

The Ionosphere - Where Short Waves Are Reflected

The Ionosphere - Where Short Waves Are Reflected, June 1935 Short Wave Craft - RF CafeAlmost certainly the earliest observed evidence of the existence of an ionosphere as part of the Earth's atmosphere is aurora activity. Alley Oop, B.C., and friends had no idea that the wavering colors were the result of high energy, charged particles from our sun interacting at altitude with the Earth's magnetic field. This article from a 1935 issue of Short Wave Craft magazine gives a nice introduction to what was known of the ionosphere at the time, which wasn't a whole lot since no in situ measurements had yet been made via sounding balloon or rocket. All that was known was inferred from the behavior of radio waves as they were affected by the charged space. It wasn't until 1926 that Scottish physicist Robert Watson-Watt coined the term "ionosphere." Although not mentioned here, it was amateur radio operators who first discovered the ability of the ionosphere to reflect and bend short wave radio waves to enable round-the-world communications. Ironically - or perhaps expectedly - the U.S. Congress in 1912 passed the Radio Act of 1912 that restricted amateur radio operation to frequencies above 1.5 MHz (a wavelength of 200 meters or less). Shortly thereafter, the FCC reclaimed much of the spectrum for itself...

Disentangling Facts from Hype re Quantum Computing

Disentangling Facts from Hype re Quantum Computing - RF Cafe"Few fields invite as much unbridled hype as quantum computing. Most people's understanding of quantum physics extends to the fact that it is unpredictable, powerful, and almost existentially strange. A few years ago, I provided an update on the state of quantum computing and looked at both the positive and negative claims across the industry. And just like back in 2019, I remain enthusiastically optimistic today. Even though the hype is real and has outpaced the actual results, much has been accomplished over the past few years. First, let's address the hype. Over the past five years, there has been undeniable hype around quantum computing - hype around approaches, timelines, applications, and more. As far back as 2017, vendors were claiming the commercialization of the technology was just a couple of years away - like the announcement of a 5,000 qubit system by 2020 (which didn't happen). There was even what I'd call anti-hype, with some questioning if quantum computers would materialize at all..."

Crosley Model 425 (Travo) Radio Service Data Sheet

Crosley Model 425 (Travo) 4-Tube Portable A.C.-D.C. Superhet. Radio Service Data Sheet, March 1936 Radio-Craft - RF CafeThis Radio Service Data Sheet is for the Crosley Model 425 (Travo) 4-Tube Portable AC/DC Superheterodyne radio which appeared in the March 1936 edition of Radio-Craft magazine. No example of this 1935-era Crosley Model 425 could be found in searches, but interestingly, the term "Travo" returns a Model 166 by that name and the same year of manufacture. I post this schematic and functional description of the manufacturers' publications for the benefit of hobbyists and archivists who might be searching for such information, either in a effort to restore a radio to working condition, or to collect archival information...

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 KR Electronics for Long-Time Support!

KR ElectronicsKR Electronics designs and manufactures high quality filters for both the commercial and military markets. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop and individually synthesized filters for special applications - both commercial and military. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. All common connector types and package form factors are available. Please visit their website today to see how they might be of assistance. Products are designed and manufactured in the USA.

col-width

Simple Mathematics for the Service Man (part 2)

Simple Mathematics for the Service Man, October 1930 Radio-Craft - RF CafeIf you are from a family of electronics hobbyists and/or professionals, then there is a good chance your grandfather and possibly even your father kept a handy-dandy list of common circuit design formulas handy. The list here Part 2 includes all the formulas on this page, which dealt primarily with vacuum tubes, the schematics for which were presented in Part 1 of the series. There was not an "app for that" back in those days. Prior to a smartphone in every pocket, notes were pinned to a lab wall or kept in a hand-written notebook...

Antenna and Semiconductor Integrated Modules (AIMS)

Altum RF Announces New Grant and Collaboration with ITRI and TMYTEK - RF CafeAltum RF, a supplier of high-performance RF to millimeter-wave semiconductor solutions for next generation markets and applications, announces a new grant and collaboration with Industrial Technology Research Institute (ITRI), the largest applied technology research institution in Taiwan, and TMY Technology Inc. (TMYTEK), a leading mmWave solution provider targeting the 5G/B5G and SATCOM markets. Altum RF, ITRI and TMYTEK will collaborate on an Antenna and Semiconductor Integrated Modules (AIMS) project for satellite communications systems. The grant comes from the Eureka Globalstars Taiwan framework. The project began in August 2022 and is slated to continue for two years. The purpose of the AIMS project is to develop a millimeter-wave antenna-in-package (AiP) module for phased array Ka-band satellite communication systems. Developing this module will make satellite communication systems...

Filter Building Made Easy

Filter Building Made Easy, December 1953 QST - RF CafeDesigning, building, and tuning low frequency filters is much easier for the person without a professional grade suite of software, fabrication, and test equipment than is RF / microwave frequency filters. Most of my design and integration work has been with system level transmit and receive racks for radar and satellite earth station installations, and typically for prototyping and/or very low quantity production. Accordingly, I often used connectorized components cascaded together where each functional block was predefined and tested. I would be handed a system input/output document that specified parameters for gain, phase noise, intercept points, noise figure, group delay, bandwidth(s), power levels, switching and settling times, current consumption, volume, weight, cost constraints, etc. That explains why my software offerings like RF & Electronics Symbols for Visio and RF Cascade Workbook all deal with system level design...

Cool Product: 3D-Printed Waveguide & Antennas

SWISSto12 3D-Printed Antenna Matrices - RF Cafe Cool Product3D printing of antenna and waveguide components has been advancing rapidly in the past few years. Early research used plastic that was then coated with a conductive substance. Once 3D printing using a metallic filament was developed to the point that the structure could withstand heat cycling, vibration, and shock associated with aerospace environments, the creation of complex, compound shapes never deemed possible with traditional machining became reality. Using proprietary additive manufacturing techniques developed in-house, virtually any form of waveguide and/or antenna can now be fabricated by companies like Swissto12, based in Switzerland. As can be seen in the included images from the Swissto12 website, the surfaces are not perfectly smooth...

 

 

 

 

 

 

 

 Loring Air Force Base, Maine - RF Cafe Loring AFB (/pictures folder)°

Building implosion 

Magnetic Variation

 

 

Engineering Job Opening

Promote Your Company on RF Cafe

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.

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...

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...

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!

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...

Get Your Custom-Designed RF Cafe Gear!

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

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...

col-width

DARPA SBI Sources for Classified Efforts

DARPA Small Business Innovation Sources for Classified Efforts - RF Cafe"The Department of Defense (DOD) seeks innovative and creative solutions to complex, classified challenges, but the DOD is currently only able to access a limited pool of companies cleared to work on them. Companies must have a facility clearance and their employees must hold security clearances to do classified work. But for a company to have a facility clearance, it must have a contract requiring classified work to justify the clearance. This current model results in a cyclical pattern that precludes the injection of new companies and ideas into the classified DOD research and development ecosystem. DARPA announced the Bringing Classified Innovation to Defense and Government Systems (BRIDGES) program, which aims to tap into innovation from companies that traditionally do not work with the DOD on classified research and development efforts. BRIDGES will connect innovators directly to the challenging problems that exist in the classified realm so they can help develop solutions. 'There's a large U.S. innovation talent base at small companies across our country that we currently aren't able to tap into for solutions to classified technology challenges..."

Switzerland's Museum of Consumer Electronics

Switzerland's Museum of Consumer Electronics - RF Cafe"For more than a decade, [Museum of Consumer Electronics] in Solothurn, Switzerland, has been a place where history buffs can explore and learn about the development and growth of computer and consumer electronics in Switzerland and the rest of the world. On display are computers, calculators, floppy disks, phonographs, radios, video game consoles, and related objects. Thanks to a new four-year partnership between the museum and the IEEE Switzerland Section, IEEE members may visit the facility for free. They also can donate their time to help create exhibits; translate pamphlets, display cards, and other written media; and present science, technology, engineering, and math workshops..."

Ubiquitous Connectivity to Land, Sea and Sky

Ubiquitous Connectivity to Land, Sea and Sky - RF Cafe"Keeping IoT applications across the world connected is a challenge, yet imperative. The term 'ubiquitous coverage' is often thrown around in the supply chain and logistics industry - and for a good reason. Breaks in the chain of visibility leave logistics vulnerable, especially as businesses scramble to keep up with the introduction of new technologies and services. This is why the challenge lies in finding a universal solution that connects IoT applications all over the world, providing a continuous view no matter where assets are. The first step to improving the deployment of IoT applications is to understand the common obstacles within the industry, like internal operations. Supply chain and logistics have long struggled to streamline internal processes to monitor the flow of goods and services from supplier to customer. And supply chain demands have only exacerbated this challenge..."

Space-Based WAAS Navigation System Modernization

Raytheon to Modernize Space-Based WAAS Navigation System - RF Cafe"The U.S. Federal Aviation Administration (FAA) has contracted Raytheon to further refine the space-based precision navigation system WAAS (Wide-Area Augmentation System). Specifically, Raytheon Intelligence & Space will modernise the system, in terms of system security, network architecture and adding dual frequency service. WAAS was developed by the Federal Aviation Administration to augment GPS services by increasing its accuracy and availability. The satellite-based augmentation system (SBAS), which provides GPS corrections for critical navigation for aircraft, first responders and other government agencies, helps ensure - for example - that pilots can land safely in difficult environments and weather..."

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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.

Homepage Archive Pages

2022:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2021:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2020:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2019:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2018:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2017:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2016:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2015:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2014:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2013:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2012:  1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 (no archives before 2012)

Innovative Power Products Couplers
Innovative Power Products Passive RF Products - RF Cafe
Exodus Advanced Communications Best in Class RF Amplifier SSPAs
Copper Mountain Technologies (VNA) - RF Cafe
Lotus Communication Systems Modular RF Component Building Blocks - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free

 

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