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 LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives Magazine Sponsor RF Cafe Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Alliance Test Equipment Centric RF Empower RF ISOTEC Reactel RF Connector Technology San Francisco Circuits Anritsu Amplifier Solutions Anatech Electronics Axiom Test Equipment Conduct RF Copper Mountain Technologies Exodus Advanced Communications Innovative Power Products KR Filters LadyBug Technologies Rigol TotalTemp Technologies Werbel Microwave Windfreak Technologies Wireless Telecom Group Withwave Sponsorship Rates RF Cafe Software Resources Vintage Magazines RF Cafe Software WhoIs entry for RF Cafe.com Thank you for visiting RF Cafe!
RF Electronics Shapes, Stencils for Office, Visio by RF Cafe

Copper Mountain Technologies (VNA) - RF Cafe

everythingRF RF & Microwave Parts Database (h1)
Axiom Test Equipment - RF Cafe

Homepage Archive - January 2023 (page 3)

See Page 1 | 2 | 3 | 4 | 5 of the January 2023 homepage archives.

Friday the 20th

Knight-Kits by Allied Radio

Knight-Kits by Allied Radio, January 1960 Radio-Electronics - RF CafeMost people involved in electronics who are over 40 years old are familiar with Heathkit. The company ran advertisements in many types of hobby and home improvement magazines and sold a very large line of built-it-yourself kits until the early 1990's. Heathkit was in its heyday in 1960 when they dominated advertising (8 pages) in the January 1960 issue of Radio−Electronics magazine (it would have arrived in the mail before Christmas). Lesser known was knight−kits, offered by Allied Electronics. Tandy Corporation, parent company of Radio Shack, bought Allied Electronics in 1970. Their ad spread in the same issue was half that of competitor Heathkit. I never had a knight−kit, but did have a few Heathkits. A search on knight−kits turned up knightkit.com, which does not appear to be formally affiliated with the company. It celebrates the "knight−kit Wireless Broadcaster and Amplifier," which is not included in this ad. This nostalgickitscentral.com website has an extensive listing of knight-kits. As you might expect, there is a plethora of vintage knight-kit items available on eBay...

3D Printing of Hydrogel-Based Electronics

3D Printing of Hydrogel-Based Electronics - RF Cafe"Hydrogels are three-dimensional (3D) polymer networks that do not dissolve in water but retain large amounts of liquids. Due to this advantageous property, hydrogels are particularly promising material platforms for both biomedical and environmental applications, as they can survive in bodily fluids or in wet natural environments without dissipating. Over the past decade, engineers and materials scientists have been developing numerous electronic devices based on soft hydrogels, including environmental and biomedical sensors, drug delivery devices, and artificial tissue. Despite the huge potential of these hydrogel-based devices, their widespread implementation has so far been hindered by their high production costs. A research team led by Dr. Nanjia Zhou at Westlake University and Westlake Institute of Advanced Studies in China have recently introduced a new strategy to enable the 3D printing of soft hydrogel electronics. Their approach, introduced in a paper published in Nature Electronics, could help to lower the production costs of num

FCC's Interactive Broadband & Cellular Maps

FCC's 8th (and 14th) Interactive Broadband Deployment Map - 2012 (2021) - RF CafeThese interactive maps were created by the FCC to illustrate the Commission's broadband and cellular deployment results. The original was found in the Eighth Broadband Progress Report which uses data underlying the National Broadband Map, as of June 30, 2011. It shows census block areas of the United States with and without access to fixed broadband of 3 Mbps download and 768 kbps upload. The FCC is now up to the Fourteenth Broadband Progress Report, published for the second half of 2020, where it states, "As of the end of 2019, the vast majority of Americans, 94% had access to both 25/3 Mbps fixed broadband service and mobile broadband service with a median speed of 10/3 Mbps. Also as of the end of 2019, mobile providers now provide access to 5G capability to approximately 60% of Americans..."

Adieu and Farewell to Lou Frenzel

https://www.mwrf.com/resources/industry-insights/article/21258418/electronic-design-remembering-a-communications-legendOne of the disadvantages of living more than six decades is learning of the passing of people you have regarded highly for many years. Even without knowing them personally, the deaths of guys like Bob Pease and Robert Lucky, whose magazine columns I read eagerly each month, always come as a shock and are met with sadness. Yesterday, news came out of Lou Frenzel, Jr., having departed from amongst us. Many links to Lou's clever and knowledge-filled articles have appeared over the years here on the RF Cafe homepage. He often incorporated his amateur radio (W5LEF) hobby into articles. Writes William Wong at Electronic Design, "I'm sad to say that my friend and colleague, Lou Frenzel, Jr., has passed away. Lou was a long-time contributor and editor at Electronic Design and Microwaves & RF. You can still read his Communiqué blog entries on Electronic Design that covered a range of topics from software-defined radio (SDR) to his time with Heathkit, as well as his blogs and assorted articles on Microwaves & RF. Lou is one of the few editors that had both the technical background and the chops to write well..."

International Kadette Model 400 Radio

International Kadette Model 400 4-Tube Battery-Operated Superhet. Radio Service Data Sheet, July 1936 Radio-Craft - RF CafeFor a long time I have been scanning and posting schematics & parts lists like this one featuring the International Kadette Model 400 4-tube battery-pperated superheterodyne radio in graphical format. As with all the other vintage articles posted, it requires running OCR on them to separate the textual content from the graphics. This particular Radio Service Data Sheet came from the July 1936 issue of Radio-Craft magazine. 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. A fine example of a restored International Kadette Model 400 tabletop radio can be seen on the RadioMuseum.org website...

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

Thursday the 19th

Mac's Service Shop: Oscillating Canine

Mac's Service Shop: Oscillating Canine, July 1960 Electronics World - RF CafeThese Mac's Service Shop techno-stories tutorially mix real-world entities with tips on troubleshooting, repair, alignment, customer service, industry news, and other relevant topics. Although not directly related to this "Oscillating Canine" episode in a 1960 issue of Electronics World magazine, mention is made of the Bon Ton Department Store. It could possibly be a reference to the modern-day The Bon−Ton store since according to Wikipedia the company was founded in 1898 (renamed Bon−Ton Millinery in 1902). The reference is actually to the store owner, who engaged Mac to convert a radio receiver to pick up weather station broadcasts from his airplane. The story's title has to do with another subject - a hard-to-get-rid-of oscillation in a transistorized radio. It is one of the first instances of solid state components and the printed circuit boards to which they are attached. Barney laments the difficulty of troubleshooting the configuration as opposed to the good 'ole vacuum tube circuits...

Additive Manufacturing to Combat Counterfeits

Additive Manufacturing to Combat Counterfeits - RF Cafe"Here's how some of the nation's universities and research groups are working to drive counterfeits out of the manufacturing supply chain. Counterfeit parts pose a serious risk to the electronics supply chain, where products that don't meet electrical safety standards and/or minimal specifications can degrade system performance, cause equipment to malfunction and create myriad other hazards. Even the U.S. Department of Defense (DoD) supply chain is vulnerable to the risk of counterfeit parts and estimates that as much as 15% of all spare and replacement parts for military electronics may be counterfeit. It seems that the bad actors behind these counterfeit parts are getting gutsier. In July, for example, a U.S. court charged one enterprise for selling counterfeit Cisco networking devices through 19 companies and multiple different online storefronts, Mirror Now reports. The operation was importing tens of thousands of fake Cisco devices from China and Hong Kong. It then resold those fakes to customers in the U.S. and overseas while falsely claiming..."

Sangamo Electric Company Condensers

Sangamo Electric Company Advertisement, October 1929 QST - RF CafeOctober 29, 1929, aka "Black Tuesday," is a date that will live in infamy. It was the beginning of the U.S. stock market crash that resulted in The Great Depression. Since magazines, particularly in the pre-digital era, went to press a month or two prior to hitting the postal system and store racks, almost nobody had any idea that by the time this issue of QST magazine was being read, investors would be hurling themselves out of high rise building windows and off tall bridges. As the country was coming to grips with what would ultimately be a nearly two decade long financial struggle, nonessential creature comforts like concert quality recorded and broadcast music equipment like that facilitated by Sangamo Electric Company's fine condensers (capacitors) were taking a back seat to worrying about keeping a job and buying food for your family. Sangamo Electric, born in 1899 as an offshoot...

Anatech Electronics Ceramic Bandpass Filters

Anatech Electronics Intros 3 Filter Models for Mid January 2023 - RF CafeAnatech Electronics offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. Three new filter surface mount, low loss ceramic bandpass filter models have been introduced - the AE1087CB1795 with a 1,087.5 MHz center frequency and a 255 MHz bandwidth, the AE3125CB1802 with a 3,125 MHz center frequency and a 120 MHz bandwidth, and the AM784B1271 with a 784 MHz center frequency and a 17 MHz bandwidth. Custom RF power filter and directional couplers designs can be designed and produced with required connector types when a standard cannot be found, or the requirements are such that a custom approach is necessary...

Comics with an Electronics Theme

Comics with an Electronics Theme in Popular Electronics Magazine - RF CafeHere are a few more tech-themed comics from vintage editions (1962 and 1970) of Popular Electronics magazine. The first comic with the transistors and fuse is really clever, IMHO. It was one of the "Parts Talk" series. 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...

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.

Wednesday the 18th

Automation in Electronics

Automation in Electronics, January 1960 Radio-Electronics - RF CafeImagine how amazed and pleased the electronics pioneers would be to see how far the science has progressed since they last walked the Earth. Hugo Gernsback, who had as the founder and editor of multiple electronics magazines and books been writing about, designing, and building electronics devices since the early days of the last century, is surely amongst them. In this "Automation in Electronics" article in a 1960 issue of Radio-Electronics, Mr. Gernsback alludes back to the year 1773 to declare John Joseph Merlin's Silver Swan automaton as the world's first instance of automation. Electronics, in conjunction with equally ingenuous mechanical contraptions, has continually provided the means of replacing tedious, sometimes dangerous, repetitive tasks with automated processes. He cites AT&T's electronics telephone circuit switching systems as an excellent example. Distractors did then and still do today claim automation displaces human workers...

Thanks Again for RIGOL Technologies' Continued Support!

RIGOL Technologies (electronics test equipment)RIGOL Technologies is transforming the Test and Measurement Industry. Our premium line of products includes digital and mixed signal oscilloscopes, spectrum analyzers, function / arbitrary waveform generators, programmable power supplies and loads, digital multimeters, data acquisition systems, and application software. Our test solutions combine uncompromised product performance, quality, and advanced product features; all delivered at extremely attractive price points. This combination provides our customers with unprecedented value for their investment, reduces their overall cost of test, and helps speed time to completion of their designs or projects.

Gridless vs. Gridded Tubes

Gridless vs. Grid Tubes, December 1936, Radio-Craft - RF CafeThis is the first of a two-part article in c1936 Radio-Craft magazine about the strengths and weaknesses, pros and cons, vices and virtues of vacuum tubes with and without grids. Author Henri Dalpayrat offers a list of no fewer than 17 drawbacks and limitations of gridded tubes. While necessary to fully control the flow of electrons from the cathode to the plate, their physical presence causes issues with parasitic capacitance, thermal noise, electrical variability due to physical differences, increased manufacturing cost, and lower reliability. Eliminate the control grid(s) and most of those problems go with it. Part 2, extolling the virtues of gridless, was printed in the January 1937 issue...

Water-Based Switch Outpaces Semiconductor Devices

Water-Based Switch Outpaces Semiconductor Devices - RF Cafe"A laser-controlled water-based switch that operates twice as fast as existing semiconductor switches has been developed by a trio of physicists in Germany. Adrian Buchmann, Claudius Hoberg, Fabio Novelli at Ruhr University Bochum used an ultrashort laser pulse to create a temporary metal-like state in a jet of liquid water. This altered the transmission of terahertz pulses over timescales of just tens of femtoseconds. With the latest semiconductor-based switches approaching fundamental upper limits on how fast they can operate, researchers are on the hunt for faster ways of switching signals. One unexpected place to look for inspiration is the curious behaviour of water under extreme conditions – like those deep within ice-giant planets or created by powerful lasers. Molecular dynamics simulations suggest water enters a metallic state at pressures of 300 GPa and temperatures of 7000 K. While such conditions do not occur on Earth, it is possible that this state contributes to the magnetic fields of Uranus and Neptune..."

What About Tech Writing?

What About Tech Writing?, September 1956 Popular Electronics - RF CafeIf you have never written an article for publication, or written a technical manual for a piece of equipment, or maybe created a test procedure document for an assembly line, then it is hard to appreciate the skill needed to assimilate information into a concise, easy-to-follow missive that an audience of a targeted skill level will find useful. Deciding what information is needed and what will cause confusion due to redundancy or misinterpretation, including not just written content but illustrations and/or photographs, can cause much consternation during the creative process. Of course as we all know from having had to deal with poorly written documents, some authors either do not care or do not know how to write effectively. Competent technical writers have always been needed, and even with modern day computerization providing spelling and grammar checkers, there still is no substitute for a quality human writer. Having written hundreds of technical articles, manuals and test procedures myself, I still suffer from indecision on content and experience the foibles of relying too heavily on word processor error checking. This 1956 article from Popular Electronics magazine says a top technical writer can expect to earn $4.50 per hour ($9,360/yr.)...

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.

Tuesday the 17th

Radio Aids to Aircraft Navigation

Radio Aids to Aircraft Navigation, August 1960 Electronics World - RF CafeThe VOR (VHF omnidirectional range) electronic aircraft navigation concept is one of the most ingenious, elegant system solutions ever designed. Using what is essentially a very simple phase comparison method, a navigation signal is generated that is precise and reliable enough to be trusted for instrument flight rules (IFR) by military, commercial, and private aviation. A physically rotating antenna in the ground station was originally used, but eventually an electronically swept method replaced it so there are no moving parts. I was trained on VOR navigation during private pilot flight training in the early 1980's, before there was a GPS. GPS has largely replaced VOR (and VORTAC) as a primary navigation tool, but a lot of airplanes still carry VOR equipment either as a backup or simply because the pilot prefers that method. IFR can be flown without VOR/VORTAC or GPS under certain conditions, but no sane pilot would try it without at least one of the two...

Unique Sound Effects in Radio

Unique Sound Effects in Radio, February 1939 Radio-Craft - RF CafeSound effects in television and movies are in the modern era generated electronically at the push of a button or the clicking of a mouse. Thousands of sound effects are available for download to enhance amateur videos. Whether you need the clopping of horse hooves, birds chirping, a street racer squealing his wheels coming off the starting line, or a baby crying in the background, it's all at your disposal - and usually at no cost. Prior to around 1960, with the exception of the incredibly phony sounding "canned" laugh tracks and audience clapping used on "live" situational comedies and variety shows, all those aforementioned sound effects had to be created real-time in the recording studio. Even if you are too old to have actually listened to old time radio shows like The Lone Ranger and The Shadow, surely you have watched an old movie where a gun shot was heard or footsteps on a wooden floor. Almost certainly those sounds were made by somebody using one of the methods shown...

Thanks to Anritsu for Their Support!

Anritsu (electronics test equipment) - RF CafeAnritsu 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. "We've Got You Covered."

Bayesian Machine Based on Memristors

A Bayesian Machine Based on Memristors - RF Cafe"Over the past few decades, the performance of machine learning models on various real-world tasks has improved significantly. Training and implementing most of these models, however, still requires vast amounts of energy and computational power. Engineers worldwide have thus been trying to develop alternative hardware solutions that can run artificial intelligence models more efficiently, as this could promote their widespread use and increase their sustainability. Some of these solutions are based on memristors, memory devices that can store information without consuming energy. Researchers at Université Paris-Saclay- CNRS, Université Grenoble-Alpes-CEA-LETI, HawAI.tech, Sorbonne Université, and Aix-Marseille Université-CNRS have recently created a so-called Bayesian machine (i.e., an AI approach that performs computations based on Bayes' theorem), using memristors. Their proposed system, introduced in a paper published in Nature Electronics, was found to be significantly more energy-efficient than currently employed hardware solutions. "Artificial intelligence is making major progress..."

How Metal Tubes Are Made

How Metal Tubes Are Made, November 1935 Radio-Craft - RF CafeIn the mid 1930s when this Radio-Craft magazine was published, hand-assembled products like metal vacuum tubes were by far the rule rather than the exception for most products be they electronics, furniture, appliances, automobiles, or toys. Many people lament - even curse - the advent of machine automation in production, but the fact is for the vast majority of things the consistency and quality of the finished component is typically much greater. Toiling at the same task, in the same location, day after day, gets unbearable very quickly for someone like me who likes to accomplish a particular job and then move on to something new - even if "new" is defined as the same type of endeavor but with different materials. There are many people, thankfully, who do not mind monotony and prefer its lack of constant challenge to employment that requires constant new challenges...

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 to PCB Directory for Continued Support!

PCB  Directory - RF CafeThe leading website for the PCB industry. PCB 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.

Monday the 16th

High Frequency Speech Processor for SSB

High Frequency Speech Processor (Brad Baker) - RF CafeRF Cafe visitor and former article contributor Brad Baker* sent a new paper he wrote entitled "High Frequency Speech Processor." In it, he presents a method for clipping of audio signals at the baseband stage of an RF transmitter in order to facilitate more efficient broadcasting of a SSB signal. Mr. Baker's process applies a Hilbert transform and uses the real part of the complex result to modulate the output. A significant difference between this and previous schemes is that here a feed-forward circuit is used rather than a closed-loop feedback circuit. Brad provided an MP3 audio file which demonstrates various levels of clipping, beginning with a raw, unprocessed sample. You might wonder why he chose the sentence, "It's easy to tell the depth of a well," for use. While I cannot say why that particular one was used, a little research showed that it is a sentence from a list called the Harvard Sentences, From "IEEE Recommended Practice for Speech Quality Measurements." Revised List of Phonetically Balanced Sentences. Specific phonemes are employed. I suppose you'd have to be a voice processing guy to know about that. Now you know...

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 - and don't miss the blog articles!


"Radiomanship", September 1966 QST - RF CafeHistory keeps repeating itself. While reading this c1966 "Radiomanship" article by Mr. Paul Amis you might think it is a contemporary piece lamenting the lack of technical understanding - or even interest in the technical aspects - of amateur radio equipment. Just as with the perpetual frustration by seasoned hobbyist veterans of all fields, concern for younger participants with their short attention spans and busyness with many other forms of time-consuming distractions causes the aforementioned old-timers to loose precious sleep. ...and yet our hobbies live on, albeit maybe under different manifestations and rules. Interestingly, this might be the first time I have read in one of these vintage QST magazines about computers capable of talking - or about computers...

The Inner Beauty of Electronic Components

Open Circuits: The Inner Beauty of Electronic Components - RF CafeA review of a new book entitled "Open Circuits: The Inner Beauty of Electronic Components" is currently posted on the IEEE Spectrum website. A few très cool photos from the book are included article. The publisher's name is, get this, No Starch Press (is that great or what?) "Eric Schlaepfer was trying to fix a broken piece of test equipment when he came across the cause of the problem - a troubled tantalum capacitor. The component had somehow shorted out, and he wanted to know why. So he polished it down for a look inside. He never found the source of the short, but he and his collaborator, Windell Oskay, discovered something even better: a breathtaking hidden world inside electronics. What followed were hours and hours of polishing, cleaning, and photography that resulted in 'Open Circuits: The Inner Beauty of Electronic Components', an excerpt of which follows. As the authors write, everything about these components is deliberately designed to meet specific technical needs, but that design leads to 'accidental beauty: the emergent aesthetics of things you were never expected to see..."

1962 Radio Shack Catalog

Radio Shack Catalog, August 1962 Popular Electronics - RF CafeRadio Shack was opened in 1921 by brothers Theodore and Milton Deutschmann, then was bought by Tandy Corporation in 1962, reportedly for $300k. As well as being an outlet for hobbyists to buy common electronics parts, Radio Shack sold its own line of electronics like radios, calculators, and stereo systems under the brand name Realistic. A lot of people don't like Radio Shack the same way many don't like Walmart - usually for no good reason. I first started shopping at Radio Shack in the mid 1970s when I needed parts to build a homebrew stereo radio receiver from an article in Popular Electronics magazine (if I remember correctly). I still like going in the store and looking around, occasionally actually buying something. Do you remember the Free Battery card they issued where you could get one free battery per month? How about the vacuum tube testers that were in the stores until the late 1970s? When our TV would crap out...

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...

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

Empower RF Systems - RF CafeEmpower RF Systems is the technological leader in RF & microwave power amplifier solutions for EW, Radar, Satcom, Threat Simulation, Communications, and Product Testing. Our air and liquid cooled amplifiers incorporate the latest semiconductor and power combining technologies and with a patented architecture we build the most sophisticated and flexible COTS system amplifiers in the world. Solutions range from tens of watts to hundreds of kilowatts and includes basic PA modules to scalable rack systems.

Sunday the 15th

Electronics Crossword Puzzle for January 15th

Electronics Theme Crossword Puzzle for January 15th, 2023 - RF CafeThis custom made Electronics theme crossword puzzle for January 15th is provided compliments of RF Cafe. 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!

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. Chances are you have never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed. An intro video takes you through the main features...

Many Thanks to 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.

Homepage Archive Pages

2024:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2023:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

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 Resistors Terminations

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

1996 - 2024


Kirt Blattenberger,


RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

Copyright  1996 - 2026

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

My Hobby Website: AirplanesAndRockets.com | My Daughter's Website: EquineKingdom


Innovative Power Products Passive RF Products - RF Cafe

Exodus Advanced Communications Best in Class RF Amplifier SSPAs