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Homepage Archive - November 2023 (page 4)

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

Thursday the 30th

Channel Master Contact Cleaner

Channel Master Contact Cleaner, October 1960 Electronics World - RF CafeAsk anyone who has ever asked me to fix something electrical or electronic and they will tell you my motto on such things, born of extensive experience, is that the vast majority of the problems are caused by poor electrical contacts of one form or another. The culprit can be a dirty or broken connector, a cold or broken solder joint, a dirty potentiometer (contact between wiper and resistor), etc. I have repaired everything from ceiling lights, to car starters, to kitchen appliances, to large screen TVs simply by finding and repairing connections. When possible, I always do a final cleaning with isopropyl alcohol and then spray with a silicon contact protector. This Contact Shield product from Channel Master would be a good choice. I can honestly say I cannot think of a single instance where the restored connection failed again. Of course sometimes it is not that simple, but enough that my initial approach to troubleshooting - unless a broken or burnt component is immediately apparent - is to unplug and inspect connectors (then plug-unplug-plug to wipe contacts clean), flip switches on-off a few times while applying various directional forces (left-right, up-down, twisting), tugging on wires, etc. People's eyes light up in amazement when a sophisticated piece of equipment starts working after doing so. Then, I me

Netherlands Electronics Market

Netherlands Electronics Market, December 27, 1965 Electronics Magazine - RF CafeThis is the electronics market prediction for The Netherlands, circa 1966. It was part of a comprehensive assessment by the editors of Electronics magazine of the state of commercial, military, and consumer electronics at the end of 1965. Philips, headquartered in Amsterdam, was singled out as a prime mover for the country. Established in 1891, Philips is still today a major economic contributor for The Netherlands. Electronics' end-of-year issue published its prognostication for Europe as a whole as well as for many individual countries. It also attempted to assess the Soviet Union's (USSR) electronics industry...

Telescope to Measure Extreme Space Weather

Telescope to Measure Extreme Space Weather - RF Cafe"Surrey University has been awarded £250,000 from the UK Space Agency to develop a new telescope that aims to boost understanding of space weather and make flying safer. The Surrey team is developing prototypes for a new High Energy Proton Telescope (HEPTEL), which aims to measure the radiation caused by solar flares in space before it reaches the Earth's atmosphere. According to the scientists, HEPTEL will monitor extremely high energy protons, the dominant particle type from solar events which can stop electronic devices from working properly once they penetrate the atmosphere. Systems on aircraft are said to be more at risk due to their altitude. 'Given the ever-increasing quantity of electronics on-board, future aircraft will need to be designed to cope with intense events, so we need research like this to enable..."

Heathkit HW-5400 HF SSB Transceiver Kit

Vintage Heathkit HW-5400 HF SSB Transceiver Kit - RF Cafe Cool ProductThis vintage Heathkit HW-5400 HF SSB Transceiver kit showed up on eBay. I have been saving the images of these unbuilt kits in order to preserve the history. The constantly growing list is at the lower right. The HW-5400 covers the 80- through 10-meter bands as well as the 10 MHz WWV frequency reference signal and the WARC bands. A video tour is posted below. A Web search on the Heathkit HW-5400 HF SSB Transceiver shows mixed reviews. Some people loved it, and others thought it was the worst transceiver Heathkit ever put out. Of course that's the way it is with most things. In the case of kits, a lot depends on the skill of the builder, because even the most proficient operator and assembler of system level parts is not necessarily a great builder and/or tuner...

Raytheon Numerical Indicator and Data Display Tubes

Raytheon Numerical Indicator Tubes and Data Display Devices Advertisement, November 15, 1965 Electronics Magazine - RF CafeBefore there were side-view neon numerical indicator vacuum tubes there were top-view neon numerical indicator vacuum tubes. Nixie tubes and pixie tubes were featured in "Readouts and Counter Tubes" in the October 1959 issue of Electronics World magazine. At the time, most were top-view designs whose size was restricted by the diameter of the tube (typically about 0.8"). Switching to a side-view format did not enable the overall width to increase much, but the aspect ratio permitted taller displays with characters that appear as normally seen (rather than being squashed in height). This advertisement in a 1965 issue of Electronics magazine for numerical indicator tubes from Raytheon were likely some of the first side-view models available from any manufacturer...

How to Target RFCafe.com for Your Google Ads

Google AdSense - it makes good sense - RF CafeOne aspect of advertising on the RF Cafe website I have not covered is using Google AdSense. The reason is that I never took the time to explore how - or even whether it is possible - to target a specific website for displaying your banner ads. A couple display opportunities have always been provided for Google Ads to display, but the vast majority of advertising on RF Cafe is done via private advertisers. That is, companies deal with me directly and I handle inserting their banner ads into the html page code that randomly selects and displays them. My advertising scheme is what the industry refers to as a "Tenancy Campaign," whereby a flat price per month is paid regardless of number of impressions or clicks. It is the simplest format and has seemed to work well for many companies. With nearly 4 million pageviews per year for RFCafe.com, the average impression rate per banner ad is about 280,000 per year (in eight locations on each page, with >17,000 pages). That's pretty good exposure for $300 per month. Some companies have expressed an interest in being able to manage their advertising accounts themselves a la the Google AdSense program...

Many Thanks to Berkeley Nucleonics for Continued Support!

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

Wednesday the 29th

What's Your EQ?

What's Your EQ?, January 1967 Radio-Electronics - RF CafeThe January 1967 instance of Radio-Electronics magazine's "What's Your EQ?" challenge contains only two puzzles. The first is a variation on the classic resistor mesh wherein a matrix of series and parallel resistors, all of a common value (10 Ω), are wired together, and your job is to determine what total resistance would be measured between the indicated two points. Author E.D. Clark implicitly suggests taking a good look at the schematic to simplify it before diving into it with circuit analysis equations. Maybe cross your eyes a bit and cross-focus like you do with those 3D images that were popular a couple decades ago. You'll be amazed (see what I just did there?) at how simple it is to calculate the equivalent resistance. The second puzzle takes a bit more work. No restrictions are placed on what additional components can be inside the boxes. To clarify, if the top switch and bulb are labeled "A" and the bottom one "B," then switch "A" switch independently controls (on or off) only bulb "A" and switch "B" switch independently controls (on or off) only bulb "B." The third wire mentioned for a simple connection would be a common point for the current flow...

Nanosatellite and Hot Air Balloon for Emergency Broadband

Nanosatellite and Hot Air Balloon for Emergency Broadband - RF Cafe"It is estimated that 95% of the planet's population has access to broadband internet, via cable or a mobile network. However, there are still some places and situations in which staying connected can be very difficult. Quick responses are necessary in emergency situations, such as after an earthquake or during a conflict. So too are reliable telecommunications networks that are not susceptible to outages and damage to infrastructure, networks can be used to share data that is vital for people's well-being. A recent article, published in the journal Aerospace, proposes the use of nanosatellites to provide comprehensive and stable coverage in areas that are hard to reach using long-range communications. It is based on the bachelor's and master's degree final projects of Universitat Oberta de Catalunya (UOC) graduate David N. Barraca Ibort. The number and financial cost of extreme weather events has constantly increased in recent decades according to the World Meteorological Organization (WMO). Climate change has vastly increased the likelihood of climate disasters occurring all over the planet. However, thanks to improvements to emergency and early warning services, the increase in extreme events has not led to an increase in the number of victims..."

Plotting Coverage Circles for Satellite Communications

Plotting Coverage Circles for Satellite Communications, January 24, 1964 Electronics Magazine - RF CafeOne of the major advantages of the age of powerful personal computers - be they in the form of desktop systems, tablets, or smartphone apps - is that for most computation-intensive tasks there only needs to be one or maybe at most a few people smart enough to know how to do them. Everyone else who has to perform the task just needs to be able to input the proper parameters to ensure a useful output. That is a significant statement, because in the days before ubiquitous computer availability and incredible computing power, highly capable engineers, scientists, analysts, and mathematicians either had to be on staff or an expert external resource was used for difficult and/or time-intensive tasks. Over time, fewer and fewer people are needed to produce very precise and reliable results. In many ways, other than the creative intuition involved in concept, creation, and execution, a large part of the product design and planning phases have been automated with the help of very capable software. This 1964 Electronics magazine article about plotting of satellite ground coverage maps is a good example...

Anatech Electronics Intros Tunable Bandpass Filter

Anatech Electronics Intros 3 Filter Models for November 29th, 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 filters have been announced for November 2023: a very nice looking 250-500 MHz tunable bandpass filter with N-type female connectors and passband insertion loss of 1.0 dB, a 312.5 MHz cavity bandpass filter with an insertion loss of 1.0 dB and a rejection of 80 dB from 425-1000 MHz, and a 3400 MHz cavity bandpass filter with a 1000 MHz pass band and a rejection of 40 dB at both 2700 MHz and 4100 MHz. 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...

The Radio Month in Review

The Radio Month in Review, December 1933 Radio-Craft - RF CafeWhen the concept of radio refrigerators was presented in a 1933 edition of Radio-News magazine, it was not quite what has become reality today. At the time, the Radio Electrical Exposition had recently been held in Madison Square Garden and the world was just getting used to the miracle of radio waves - and refrigerators for that matter. Radio-refrigerators never did make their way into the consumer market. Fast-forward 80 years and now we're seeing the advent of radio-refrigerators re-emerge, only in a completely different format. This time, rather than playing shows from local commercial broadcast stations, these appliances are communicating with Wi-Fi routers to allow owners to check on status and contents from remote locations. In other news, the editors report on a scheme to use a remote-controlled airplane, signaled by a Tesla spark gap transmitter, to drop bombs inside tornados in order to break up and stop their destructive presence (that drawing of a low-wing, single-engine monoplane that looks a lot like a Piper Cherokee, was way ahead of its time). There is also a photo of Major Armstrong's original lab notebook sketch of his idea for a regenerative receiver circuit...

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 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.

Tuesday the 28th

Printing Radio Sets on Calling Cards

Printing Radio Sets on Calling Cards, May 1946 Popular Science - RF CafeSome of the earliest printed circuit boards were literally printed onto a ceramic substrate using silk-screening techniques. For that matter, silk cloth was used as the pattern mask; hence the name silk-screen. A paste of silver particles was squeegeed through the mesh, and the resulting circuit pattern was fired in an oven to solidify and adhere the metal to the substrate. Holes were then drilled to accept component leads. After inserting the leads through the holes, hand-soldering completed the assembly. It was a game-changing technology. Not only was time and space saved and a more robust product the result, but the process eliminated miswiring and made tracing out interconnections much simpler when troubleshooting. According to this 1946 Popular Science magazine article, the motivation for developing this technique was the proximity fuse during World War II. Ditto for the tiny "peanut tubes" used. Necessity is the mother of invention, as the saying goes...

Heathkit IM-104 Solid-State Voltmeter Kit

Vintage Heathkit IM-104 Solid-State Voltmeter Kit - RF Cafe Cool ProductThis vintage Heathkit IM-104 Solid-State Voltmeter kit showed up on eBay. Although I only own a couple Heathkit items, I have been saving the images of many unbuilt kits in order to preserve the history. They regularly appear and disappear on eBay all the time - some models more than others. One of the earliest instances of the IM-104 Solid-State Voltmeter being offered for sale was in the Spring 1976 Heathkit catalog (p54), at a cost of $94.95 ($504.55 in 2023 money per the BLS) in kit format, or $149.00 full built and tested. That was/is a lot of cash to lay down for a multimeter that measures AC/DC voltage and current, and resistance. However, the alternative if you needed a high input impedance instrument, this was still cheaper than buying a vacuum tube voltmeter (VTVM), and it is much smaller, lighter weight, and portable due to being powered by batteries (a D cell and four AA cells). An article like "The Case for the Transistorized Multimeter" was evidently deemed necessary in the 1968 issue of Popular Electronics magazine to convince the VTVM faithful that the newfangled DMM would make their lives better...

Japan Stresses Research

Japan Stresses Research, October 18, 1965 Electronics Magazine - RF CafeElectronics magazine editor Lewis H. Young dedicated a series of issues in 1965 to reporting on the state of electronics research and production in Japan. The December 13 edition had many articles on the subject. The world was still in the early phase of a major transition from vacuum tubes and discrete components to transistors and integrated circuits. Japan was at the leading edge of that effort - and it was very successful. Ample evidence of the not-quite-there-yet status of the transition is all the advertisements in this edition of the magazine. Products showcased by manufacturers were discrete, not integrated - that applies to both electronic and mechanical subjects. When you look at those components and assemblies, you get a feel for what made them work because the individual parts are in view. Many modern products are integrated into packaged and tested subassemblies that are ready to be integrated into higher level products. High performance, high functionality products can thereby be developed and produced at a blazing speed. Both the professional and the DIY communities have benefitted greatly...

Deep Space Optical Communications

Deep Space Optical Communications - RF Cafe"NASAs Deep Space Optical Communications (DSOC) experiment has beamed a near-infrared laser encoded with test data from nearly 10 million miles (16 Mkm) away - about 40 times farther than the Moon is from Earth - to the Hale Telescope at Caltech's Palomar Observatory in San Diego County, California. This is the farthest-ever demonstration of optical communications. Riding aboard the recently launched Psyche spacecraft, DSOC is configured to send high-bandwidth test data to Earth during its two-year technology demonstration as Psyche travels to the main asteroid belt between Mars and Jupiter. NASA's Jet Propulsion Laboratory aboard Psyche capable of sending and receiving near-infrared signals - locked onto a powerful uplink laser beacon transmitted from the Optical Communications Telescope Laboratory at JPL's Table Mountain Facility near Wrightwood, California. The uplink beacon helped the transceiver aim its downlink laser back to Palomar (which is 100 miles, or 130 kilometers, south of Table Mountain) while automated system..."

Ford-Philco Car-Radio Model F-1440

Ford-Philco Car-Radio Models F-1440 and F-1442, August 1937 Radio-Craft Radio Service Data Sheet - RF CafeMost of the earliest automobile radios had the electronics mounted in a metal box mounted under a seat or in the trunk, separate from the dashboard tuning dial. Ditto for the power supply. The bulk and weight prevented colocation. This 1937-vintage Ford-Philco model F-1440 radio is one for which I was able to find a couple examples for sale on eBay. One claims to be fully functional and the other is in pretty rough shape. The August 1937 issue of Radio-Craft magazine included the schematic and tuning procedure for it. If your era car or truck came without a radio and you would like to finally upgrade, this is your opportunity ;-)

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeBanner Ads are rotated in all locations on the page! RF Cafe typically receives 8,000-15,000 visits each weekdayRF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 17,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. Your Banner Ads are displayed on average 280,000 times per year! New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. If you need your company news to be seen, RF Cafe is the place to be...

Many Thanks for Alliance Test Equipment's Support!

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

Monday the 27th

Westinghouse Centenary

Westinghouse Centenary, May 1946 Popular Science - RF CafeThese rather nicely done paintings celebrating the "Westinghouse Centenary" appeared in a 1946 issue of Popular Science magazine. The centenary marked the 100th year since the birth of George Westinghouse, not the company. We electrical and electronics types know Westinghouse Electric Corporation, founded by George Westinghouse in 1886, as a company that makes electrical distribution equipment, electronics products and systems, household appliances, industrial motors and generators, jet engines, and other high tech products. However, George Westinghouse was famous first for his locomotive air brake design. He teamed up with Nikola Tesla to battle Thomas Edison over the superiority of AC over DC for building a large scale distribution system. The caption of one picture mentions that DC systems could only cover 16 square miles. Line losses due to high currents dissipated a large part of the power. AC allowed voltages to be cranked way up to keep current down. Unlike DC, AC can be efficiently and economically transformed up and down. However, modern principles are allowing high voltage direct current (HVDC) to be implemented from generation plants to AC substations...

The Moon: We Look Before We Leap

The Moon: We Look Before We Leap - Ranger 6, January 24, 1964 Electronics Magazine - RF CafeCongress was breathing hard down the neck of NASA while Ranger 6 was being prepared for its surveillance mission to the lunar surface. In 1962, Ranger 3, the first to carry a TV camera, went into orbit around the sun after missing the moon. Ranger 4 (dubbed "Brainless I") impacted the moon but did not send back any data. And Ranger 5 lost power after launch and missed the moon by about 450 miles. Time was running out to collect data for use in fulfilling the challenge issues by President John F. Kennedy on May 25, 1961, to "...commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to the Earth." That challenge was successfully met by the Apollo 11 mission partially on July 21st, 1969 by landing Neil Armstrong and Buzz Aldrin on the moon, and then fully on July 24th when they (Armstrong, Aldrin and Michael Collins) returned safely to Earth. Ranger 6 unfortunately ended in failure on February 2nd, 1964, when its TV camera did not return any images...

Stratospheric 5G Communications

Stratospheric 5G Communications - RF Cafe"A team of UK companies led by Stratospheric Platforms Limited (SPL), a Non Terrestrial Networks telecoms developer, has won a contract trialing advanced airborne 5G connectivity from a Britten-Norman Islander. Aircraft manufacturer Britten-Norman will be providing key design and trials support for the project, with Marshall Futureworx providing cooling systems technology. SPL is pioneering the concept of using a High-Altitude Platform (HAP) with airborne antenna to provide wide scale coverage of high performance 5G from the stratosphere. The goal of the project is to deliver an unmanned, liquid hydrogen-powered aircraft, designed with a 56-metre wingspan that will, due to its lightweight structure and significant power source, enable a flight endurance of over a week. The first phase of the contract will see SPLs 5G airborne phased array integrated to a Britten-Norman Islander, with flight trials..."

Silvertone Models 4488 and 4588

Silvertone Models 4488 and 4588 (Chassis No.101412) and 4488A and 4588A (Chassi No. 101412A) Set Radio Service Data Sheet, June 1937 Radio-Craft - RF CafeThe Silvertone brand of radios was manufactured for Sears, Roebuck & Company by Colonial Radio. This particular mid-1930s Model 4488 that covered broadcast, shortwave, and police bands was very popular, and the Radio Service Data Sheet published in the June 1937 issue of Radio-Craft magazine was a full two pages. NostalgiaAir.com has the more extensive Rider data pack. It had a very ornate wood laminate decor, along with many 'extra' features found only in high-end radios of the day - such as a Flash Tuner! More detail can be found on the RadioMuseum.org website...

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 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.

Sunday the 26th

Electronics Theme Crossword for November 26th

Electronics Theme Crossword Puzzle for November 26th, 2023 - RF CafeThis custom RF Cafe electronics-themed crossword puzzle for November 26th contains words and clues which pertain exclusively to the subjects of electronics, science, physics, mechanics, engineering, power distribution, astronomy, chemistry, etc. If you do see names of people or places, they are intimately related to the aforementioned areas of study. Being that "Z" is the 26th letter of the alphabet, it is used as the first and/or last letter of many words in today's crossword puzzle - as well as in-between. Those clues are marked with an asterisk (*). As always, you will find no references to numbnut movie stars or fashion designers. Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds of them dating back to the year 2000. Enjoy...

How to Target RFCafe.com for Your Google Ads

Google AdSense - it makes good sense - RF CafeOne aspect of advertising on the RF Cafe website I have not covered is using Google AdSense. The reason is that I never took the time to explore how - or even whether it is possible - to target a specific website for displaying your banner ads. A couple display opportunities have always been provided for Google Ads to display, but the vast majority of advertising on RF Cafe is done via private advertisers. That is, companies deal with me directly and I handle inserting their banner ads into the html page code that randomly selects and displays them. My advertising scheme is what the industry refers to as a "Tenancy Campaign," whereby a flat price per month is paid regardless of number of impressions or clicks. It is the simplest format and has seemed to work well for many companies. With nearly 4 million pageviews per year for RFCafe.com, the average impression rate per banner ad is about 280,000 per year (in eight locations on each page, with >17,000 pages). That's pretty good exposure for $300 per month. Some companies have expressed an interest in being able to manage their advertising accounts themselves a la the Google AdSense program...

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.

Friday the 24th

Sears, Roebuck & Co. Mail Order Operations

Sears, Roebuck & Co. Mail Order Operations, May 1943 Popular Mechanics - RF CafeThe demise of Sears, Roebuck and Co. is very disappointing to me. As with many Americans (and Canadians) of my era and prior, I grew up with Sears being literally (in the true sense of the word, not the faux usage like "I literally thought I would die when she told me...") a household name. We had Kenmore kitchen appliances (some, not all), clothes irons and hair blowers, and of course Craftsman tools and a DieHard battery in the family sedan, and some Toughskin clothes at the start of the school year. We never, to my memory, had a Silvertone radio or record player. It's not that the parents were Sears fanatics, just that our limited budget mandated buying durable goods at a fair price. My own workshop is dominated by Craftsman tools, many of which I have had for fifty years. Analysts say poor management and a failure to embrace online sales were the primary causes for ultimate doom. This "A City in a Store" article appearing in a 1937 issue of Popular Mechanics magazine highlights the catalog sales business of Sears, along with the amazing conglomerate of operations supporting both that and the brick and mortar retail sales locations. Just as The Decline and Fall of the Roman Empire is a weighty, multi-volume tome analyzing the human failings behind the tragedy, this Smithsonian magazine article entitled The Rise and Fall of Sears assesses the Sears debacle. The conspiratorial side of me suspects globalist true believers are directing and facilitating the breaking down of Western stalwart institutions in order to erase history. The schools nowadays do not teach the accomplishments and heroic parts of our past - only atrocities like slavery and child labor. Flooding the country with aliens having no connection...

1948 U.S. Radio and Television Stations

U.S. Radio and Television Stations January 15, 1948, March 1948 Radio-Craft - RF CafeSignificant advances in electronics - and all other kinds of technology for that matter - occurred during World War II, which in conjunction with the U.S. government selling surplus equipment at the end of that war at very low prices, cause a boom in consumer electronics markets. The established radio business and the fledgling television markets were abetted by quickly expanding numbers of broadcast stations. This chart appearing in Radio-Craft magazine from early 1948 show the number of currently licensed AM, FM, and TV stations, with projections out 20 years to 1968. I don't have the data from 1968, but almost certainly the numbers were much larger than predicted, fueled largely by portable radios in automobiles and hand-carried models. Transistorized circuits (the transistor was invented in 1947, just a month before this chart was made) with their smaller size, smaller battery requirements, more rugged construction, improved circuit designs, and higher reliability provided another major kick to the market in the early-mid 1960s...

Thermal Transistors Handle Heat

Thermal Transistors Handle Heat with No Moving Parts - RF Cafe"Electronic transistors are central to modern electronics. These devices precisely control the flow of electricity, but in doing so, they generate heat. Now, researchers at the University of California, Los Angeles have developed a solid-state thermal transistor - the first device of its kind that can use an electric field to control the flow of heat through electronics. Their study, which was recently published in Science, demonstrates the capabilities of the new technology. 'There has been a strong desire from engineers and scientists to control heat transfer the same way we control electronics, but it has been very challenging,' says study lead author Yongjie Hu, a professor of mechanical and aerospace engineering at UCLA. Historically, electronics have been cooled down with heat sinks that passively draw the excess heat away. More active approaches to thermal management have also been proposed, but these often rely on moving parts or fluids and can take a long time - typically minutes to hours..."

Men Who Made Radio - Frank Conrad

Men Who Made Radio - Frank Conrad, June 1930 Radio-Craft - RF CafeThe name Frank Conrad probably does not sound familiar to most people in the electronics communications field today, but at one time he was the assistant chief engineer to the Westinghouse Company. Back when voice radio (as opposed to Morse code, aka CW) was being pioneered, Mr. Conrad was widely known for his efforts in commissioning the country's first commercial broadcast installation - KDKA in Pittsburgh, Pennsylvania. His arranging for live coverage of election night results in 1920 is credited for launching a huge interest by consumers in purchasing radio sets for their homes (Warren Harding beat James Cox that night, BTW). Toward the end of his career, Conrad was active in helping develop television broadcast standards. Fortunately for us, his electromechanical system gave way to a fully electronic system...

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.

Thursday the 23rd

News Briefs

News Briefs, September 1967 Radio-Electronics - RF CafeThese "News Briefs" features from Radio-Electronics magazine (c1967) are always interesting. As has always been the case, some of the items predicting the future of technology are either too wacky to ever be realized, or science has not yet advanced far enough. Many - maybe most - products and concepts have advanced far beyond even what the-present-day inventors imagined. This month's column is full of mostly the latter types. A "lineless" (i.e., cordless) telephone (not cellphone) is demonstrated by Bell Telephone Labs, with no mention of the frequency band. The "pocket television," presented by Sony, nowadays takes the form of a smartphone, and the programming is received via an Internet connection rather than directly from local broadcast towers. The "world's smallest detect," operating in the infrared was built on a germanium substrate (maybe the bumble bee thought it was a geranium substrate?). When I first saw RCA's giant UHF antenna, I thought it was the barrel of some sort of cannon. Turns out those slots are not cooling ports but radiation ports...

Anatech Electronics Intros 3 More Filters for November

Anatech Electronics Intros 3 Filter Models for November 22th, 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 filters have been announced for November 2023: a 10 MHz LC bandpass filter with BNC connectors with a bandwidth of 2.0 MHz, a 769-855 MHz cavity bandpass filter with N-type connectors and a ripple of 0.2 dB maximum, and a 1000-2000 MHz cavity bandpass filter with SMA connectors having a rejection of 20 dB minimum at 2100 MHz. 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...

Fuses for Electronics

Fuses for Electronics, July 1972 Popular Electronics - RF CafeDeciding which fuse to use as a replacement for a blown fuse is usually a simple matter - read the part number or electrical parameters (current, voltage) off the package and make sure of its type (fast or slow blow). Of course whenever a fuse blows, you usually have more or a problem than just a bad fuse. Deciding which fuse to use when designing a circuit which requires overcurrent protection requires a lot more consideration. This 1972 Popular Electronics magazine article from fuse making company Bussmann's Charles James gives a brief introduction to the kinds of parameters you need to factor into a selection. There's more to it in most cases - especially for a shippable product - than measuring the current under normal operating conditions and then adding some arbitrary buffer like 20%. Extreme ambient temperature requires derating, mechanical conditions during operation like high vibration or impact, time delay for more than a short-lived transient event...

"As God As My Witness, I Thought Turkeys Could Fly"

WKRP in Cincinnati: "As God As My Witness, I Thought Turkeys Could Fly" - RF CafeAnyone who watched the WKRP in Cincinnati sitcom back in the 1970s has to remember what was one of the funniest episodes ever. Here is the 4 minutes that made Prime Time history. In this Thanksgiving episode, station owner / manager Arthur Carlson decided he would surprise the community with good deed - that doubled as a promotional stunt for his radio station - by dropping turkeys from a helicopter for lucky shoppers at the local shopping mall. Watch the disaster unfold as Les Nessman reports live, and then see Carlson's final comment that is still used or alluded to in many comic routines. Posting this video is an RF Cafe tradition. Have a Happy Thanksgiving!

Fada 103 Fadalette / Stewart-Warner 108 / DeWald 54 Dynette

Fada 103 Fadalette, Stewart-Warner Series 108, DeWald 54 Dynette Sets Radio Service Data Sheet, May 1933 Radio-Craft - RF CafeEven in the early days of radio, some big-name manufacturers built versions of their sets for the purpose of re-branding by another company. Sears, Western Auto, Montgomery Ward, JC Penny, and others had the own radio lines made by someone else. Here is an instance where three radios - at least their electronics chassis - had identical (or nearly so) innards. As was common at the time with AC/DC sets, one terminal of the AC power line attached to the metal chassis as a common voltage reference, which meant there was a 50-50 chance that the nonpolarized plug would be inserted into the wall socket in a manner that connected the chassis to 120 VAC rather than to ground (neutral). Everything on the outside was electrically isolated, by nonconductive components (enclosure, knobs, switches), but many an unwitting radio owner got shocked when attempting to service the set while it was plugged in (even if just removing or inserting vacuum tubes). Designers eventually devised means of totally isolating the metal parts - like installing a traffic light at an intersection after enough people died in accidents there...

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. 

Wednesday the 22nd

The ABC of Gears and Gear Cutting

The ABC of Gears and Gear Cutting, January 1944 Popular Mechanics - RF CafeI love a finely crafted gear as much as I do a fancy vacuum tube. Worm gears are my favorite, maybe because they are what I call the "diode" of gears. Due to their construction, applying a torque force to the cylindrical worm gear transfers its rotation to the circular mating gear (worm wheel); however, applying the torque to the worm wheel will not impart a torque backward to the cylindrical worm gear. It's one-way action accommodates a force transfer in just one direction, like a diode. There is no need for a lock or ratchet to prevent the output from affecting the input. That is why tuning pegs on stringed instruments use worm gears. It is why the drive gears on telescope axes use worm gears. Winches use worm gears. One of the downsides of worm gears is that there is no rolling force between surfaces - only a sliding force - so good lubrication is essential to prevent excessive wear. This "ABC of Gears and Gear Cutting" story from a 1944 issue of Popular Mechanics magazine is a fairly in-depth dive into gear theory and manufacturing - and not just for worm gears...

No ARRL Membership Renewal for Me

No ARRL Membership Renewal for Me - RF CafeRegrettably, I will not be renewing my membership with the American Radio Relay League (ARRL) after it expires in March 2024. The ARRL recently announced that dues will increase from $49 to $59 per year (+20%) -- not unreasonable since they have remained the same since 2016 (30% inflation since then). However, that does not include the print version of QST magazine anymore; you need to pony up another $25 for a hard copy. Now, if the established value of print is $25 (let's use just $20), then the former membership w/o print would have been only $(49-20) = $29. That makes the increase for just membership a factor of two: (59/29=2) -- a 100% change! Bidenomics has been steadily breaking my financial back, so costs need to be trimmed; ARRL is a casualty. I'll miss sitting in bed reading QST and looking for stories to reference here. In contrast, RF Cafe prices have remained steady (advertising has decreased), so my effective income has gone way down in the past three years. Nobody gives me a raise :-(

Rohde & Schwarz Ad from December 1965

Rohde & Schwarz Ad, December 13, 1965 Electronics Magazine - RF CafeThis might be one of the first advertisements for Rohde & Schwarz (R&S) test and measurement (T&M) products to appear in a U.S. publication (December 13, 1965 Electronics magazine). A brief search for earlier instances did not turn up anything prior to 1965. Please contact me if you have seen one. R&S, as you probably know already, is now a major player in the communications T&M world. Hewlett Packard (HP) of course was one of the largest - if not the largest - maker of spectrum analyzers, network analyzers, noise figure test sets, modulation generators and analyzers, signal generators, o-scopes, etc., up through about the 1980s - maybe into the 1990s. Once the cellular and wireless everything markets took off, Rohde & Schwartz test equipment (TE) began appearing on lab test benches more and more frequently. Engineers and technicians quickly learned to appreciate the new advanced features that older industry stalwarts were slow to adopt and incorporate. Then, in the early 2000s, HP decided to divest its TE market into a new company with a weird, totally unfamiliar name (Agilent, now weirdly named Keysight), leaving a lot of customers with strong brand loyalty feeling abandoned (gotta admit I was one of them). The switch to other brands was made much easier from then on, and, at least where I worked at the time, labs and production test areas began mutating in color from gray to light blue. Since this was first posted, a guy wrote to tell me he found a few pieces of brand new R&S test equipment in the attic of an old house in Germany (none of the models in this ad). I put him in touch with Rhode & Schwarz corporate to see whether they would be interested...

The Best Metal for an Antenna

The Best Metal for an Antenna (QST December 2023) - RF CafeYou might recall the April 2023 issue of the ARRL's QST magazine featuring an article "The Better Antenna: Copper Versus Aluminum." It was, as could be discerned when reading, written for Fools. Jose Luis Giordano decided to use the occasion to write a "real" article explaining the pros and cons of copper and aluminum. "The Best Metal for an Antenna" appears in the December 2023 issue of QST. He includes data and calculations for wire sag as a function of weight, length, and tensile strength (resistance to stretching). He mentions the curve formed under the influence of gravity being called a "catenary." I remember learning in math class that its mathematical function is the hyperbolic cosine (cosh), and that catenary stems from the Greek word meaning "chain," from how a chain, cable, or rope sags. Someone posted a scan of the full article on the Radio Club of Chile website. For some reason, ARRL does not make the contents of QST available to non-members...

FADA "Special" and FADA "7"

FADA "Special" Model 265-A and FADA "7" Model 475-A Radio Service Data Sheet, September 1930 Radio-Craft - RF CafeThe following announcement was posted in the September 1930 edition of Radio-Craft magazine regarding Radio Data Service Sheets: "We are pleased to announce that RADIO-CRAFT has taken over the subscription list of 'RADIO SERVICE,' formerly published in Dallas, Texas. All subscribers of record to RADIO SERVICE will receive RADIO-CRAFT until the expiration of their subscriptions." Prior to that, the "Radio Service" company must have contracted with Radio-Craft to provide the information. This one in particular features the Fada Radio and Electric Company of Long Island, New York, models 265-A and 475-A. Thanks to the nomenclature plate on the "7" listed on eBay, we see that FADA stands for F.A.D. Andrea, Inc. We still don't know what the initials stand for, though. I had the Wayback Machine™ capture a copy of the listing so that the photos will be available in perpetuity. A magazine ad for the FADA "Special" on the RadioMuseum website shows a price of $95, which in 2023 money is the equivalent of $1,709 - yow!

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 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!

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