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Homepage Archive - January 2024 (page 3)

See Page 1 | 2 | 3 | 4 | of the January 2024 homepage archives.
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Sunday the 21st

Electronics Theme Crossword for January 21st

Electronics Theme Crossword Puzzle for January 21, 2024 - RF CafeThis custom RF Cafe electronics-themed crossword puzzle for January 21st contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc., which I have built up over more than two decades. Being the 21st day, words containing the letter "U" are marked with an asterisk (*). Many new words and company names have been added that had not even been added to the world's technical lexicon when I started in the year 2002. As always, this crossword contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme. You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which, if you don't already know, might surprise you. The technically inclined cruciverbalists amongst us will appreciate the effort. A full list of all RF Cafe crosswords is at the page bottom. 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...

Friday the 19th

ABC's of Color Television

ABC's of Color Television, July 1954 Popular Science - RF CafeThis 1954 Popular Science magazine piece on "The ABC's of Color Television" is useful, but it is strange that a labeled picture of the composite video signal is not provided to go along with the definitions of the various parts of it (front porch, back porch, red/green/blue video, color killer for black & white signals, I, Q and Y signals, etc. ). Nor is there a labeled picture of any of the components of a color TV (CRT, deflection coils, horizontal and vertical sync controls, hue and brightness controls, etc.). Of course in 1954 not many people had ever even seen a color television set, much less make adjustments on one. It wasn't until around 1965 that most Prime Time shows were broadcast in color. The first commercial color television broadcast occurred in 1954 during the Tournament of Roses Parade. Price was a major deterrent since a typical cost in equivalent 2024 money was around $5,000...

FCC: Connected Cars Stalk, Harass, Intimidate, Control

FCC: Connected Cars Stalk, Harass, Intimidate, Control - RF CafeThe FCC just wants part of the action for itself. - "The argument goes that since new cars make it increasingly easy for passengers and drivers to access hands-free communication tools, find-your-car services, and other technological bells and whistles, these services have been used to 'stalk, harass, and intimidate survivors of intimate partner violence.' Letters were sent to nine car manufacturers, citing a recent report in the NYT (paywall) titled 'Your car is tracking you. Abusive partners may be, too.' The letter reads: '...the report recounts in detail how a woman was tracked by a former partner through connected services associated with the car she was using. In another example, a man used his remote access to the car to harass his wife by activating the car's lights and horns a night and running the car's heat on hot days. The report finds that car makers have been reluctant or unwilling to assist victims of this abuse or restrict abusive partner access to the car's connectivity and data..."

Eliminate Risk of Fatal Electric Shock with the GFI

Eliminate Risk of Fatal Electric Shock with the GFI, April 1974 Popular Electronics - RF CafeWhen I first started working as an electrician apprentice in the summer of 1974 as part of my high school vocational program, ground fault interrupter (GFI) receptacles and circuit breakers were not mandated by the National Electric Code (NEC). It was only a little more than a decade earlier that UC Berkeley professor Charles Dalziel invented the GFI circuit while researching the effects of electrical current on humans (electrocution). By the late 1970s, shortly before I enlisted in the USAF to begin my electronics career, GFI (now referred to as GFCI) protection was required for areas near water like in bathrooms and outside. Nowadays the NEC calls for GFIs in bathrooms, kitchens, garages, outdoors, and any place where wet or damp conditions might exist. In Arc Fault Circuit Interrupters (AFCI) have been required on may types of circuits since 1999. AFCIs detect the presence of arcing and open the circuit if present. Early AFCI devices were notoriously overly sensitive and often tripped on imperfect but safe vacuum cleaners, kitchen blenders, and hair dryers. Proposed 2017 NEC requirements for GFCI and AFCI circuit applications have been greatly expanded - undoubtedly due partly to the successful lobbying efforts of device manufacturers. The cost for new homes will increase accordingly. Melanie's sister and her husband had a big new house built a couple years ago and while we were visiting, they complained about a new humidifier that was not working anymore...

Please Welcome Crane Aerospace & Electronics as a RF Cafe Supporter

Crane Aerospace & Electronics - RF CafeCrane Aerospace & Electronics' products and services are organized into six integrated solutions: Cabin Systems, Electrical Power Solutions, Fluid Management Solutions, Landing Systems, Microwave Solutions, and Sensing Components & Systems. Our Microwave Solution designs and manufactures high-performance RF, IF and millimeter-wave components, subsystems and systems for commercial aviation, defense, and space including linear & log amplifiers, fixed & variable attenuators, circulators & isolators, power combiners & dividers, couplers, mixers, switches & matrices, oscillators & synthesizers.

Do You Know Your Bipolar Transistors?

Do You Know Your Bipolar Transistors?, September 1973 Popular Electronics - RF CafeMr. Lothar Stern, of Motorola Semi, published a 3-part series on transistor theory in Popular Electronics magazine in 1973. This is part 2. Part 1 introduced the basics of the bipolar transistor, and this follow-on article starts addressing transistor circuit configurations - common emitter, common gate, common collector, Darlington, differential - as well as presenting gain equations and delving a bit into the physical construction of the semiconductor elements. Part 3 describes the newest processes in use at the time and what was available for low power and high power RF applications...

National Toxicology Program Cancels Cellphone Radiation Study

National Toxicology Program Cancels Cellphone Radiation Study - RF CafeThe National Institute of Health's (NIH) National Toxicology Program (NTP) announced it has cancelled its Radio Frequency Radiation (RFR) study because, and I quote, "The research was technically challenging and more resource-intensive than expected. No additional RFR studies are planned." The challenging part was trying to establish a high confidence correlation between mouse and rat testing and human body testing, since without direct equivalent empirical testing on humans, only educated guesses could be made. Short of Axis countries' type of testing on humans during World War II, the methods and levels of radiation could not be used on people. No mention is made of what, if any, other test programs were/are in process or planning. Interestingly, the report states, "However, the studies question the long-held assumption that RFR is of no concern as long as the energy level is low and does not significantly heat the tissues," and that, "NTP studies of RFR used in 2G and 3G cellphones do not apply to 4G or 5G technologies." The good thing is now that money can go toward caring for the millions of new illegal immigrants entering the country since 2021.

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, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We Are the World's Matchmakers" Smith chart design. These would make excellent gifts for husbands, wives, kids, significant others, and for handing out at company events or as rewards for excellent service. My graphic has been ripped off by other people and used on their products, so please be sure to purchase only official RF Cafe gear. I only make a couple bucks on each sale - the rest goes to Cafe Press. It's a great way to help support RF Cafe. Thanks...

Thursday the 18th

Sunshine Becomes Electricity

Sunshine Becomes Electricity, July 1954 Popular Science - RF CafeA lot of people think the modern day solar energy craze is a relatively new phenomenon, but old guys like me remember back in the early 1970s, during the Arab Oil Embargo, when we were promised that massive arrays of photovoltaic (PV) cells would save the world from its dependence on foreign oil suppliers. At the time, the massive oil reserves below the ground here in the USA, and in easily accessed offshore regions, were not known. PV cell manufacturers (small by today's standards) were popping up around the country. I remember one in particular, Solarex Corporation, which served as a sort of poster child for solar power, went toes-up due to underperformance in conversion efficiency and excessive costs. Tragically, we were told by "experts" that between wind, solar, hydro, and nuclear, that electricity would be practically free, and many homes and businesses had electric heating installed in the form of baseboard electric heaters. Now, with closing nuclear plants after the 3-Mile Island incident and the current government shutting down gas and oil mining and pushing expensive "renewable" energy sources, people are getting winter electricity bills over $400/month. This 1954 Popular Science magazine article reports on some of the very earliest attempts at solar cell manufacturing...

Anatech Electronics Intros 3 New Filter Models

Anatech Electronics Intros 3 New Filter Models for Mid-January 17, 2024 - 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 mid-January 2024: a 750 MHz LC bandpass filter with a bandwidth of 50 MHz, a 70 MHz LC bandpass filter with a 10 MHz bandwidth, and a 3400 MHz highpass filter with an insertion loss of 1.5 dB. 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...

$5.00 for Best Short Wave Kink

$5.00 for Best Short Wave Kink, January 1935 Short Wave Craft - RF CafeEven with all of today's prefabricated components, gizmos, and tools - at incredibly cheap prices - there are still many people who prefer to make their own non-standard parts and even tooling when tinkering on a project. Many hobby magazines have monthly columns dedicated to hints, tips, shortcuts, ideas, etc. to solve, remedy, conquer, etc., the many kinks, problems, challenges, twists, hitches, snags, etc. of the task at hand. The aforementioned words can be found in the titles of those columns. Short Wave Craft magazine ran a feature titled "$5.00 for Best Short Wave Kink" that rewarded readers for submitting nifty ideas. Contemporary magazines and websites still offer cash rewards, typically in the $25-$50 range. In today's money that $5 is equivalent to around $112...

X-Rays Reveal New Phase of Matter

X-Rays Reveal New Phase of Matter - RF Cafe"In a scientific breakthrough that could reshape our understanding of how light interacts with matter, researchers from the Attoscience and Ultrafast Optics group at the Institute of Photonic Sciences (ICFO) in Barcelona, Spain have discovered a new phase of matter, aptly named a 'light-matter hybrid.' The findings, published inNature Communications, not only reveal a previously unseen state of material, but also open doors to potential applications in photovoltaics, high-power electronics, and beyond. In the hybrid, the material's properties are altered according to the strength of pulses light, in one case dropping resistance to near zero. At the heart of this technique is attosecond x-ray absorption spectroscopy, which allowed the ICFO research team to study how electrons behave on timescales as short as a billionth of a billionth of a second (an attosecond) when exposed to powerful infrared radiation. This was achieved through a classic pump-probe technique, where an infrared laser pulse excites electrons into high energy states, and an x-ray beam subsequently probes the energy distribution..."

A Variable Wavelength Antenna

A Variable Wavelength Antenna, January 1935 Short Wave Craft - RF CafeThere are many designs for multiple-wavelength antennas available. Some use resonant "traps" and specific length sections of lines to change the effective RF length according to specific frequency bands, and others employ complex phasing of multiple antennas to a single-point feed. Doing so allows operation across bands that do not necessarily fall within or close enough to harmonic ratios, while still presenting decent VSWR to the transceiver for acceptable performance. Still, nothing beats a single, finely tuned antenna for each band of operation, or for that matter an antenna whose length is trimmed to operate at peak efficiency even within sub-bands. It is possible to "match" just about any antenna impedance to a transmission line and transceiver, there will always be loses in efficiency and thus loss in power due to resistive losses in matching networks and transmission lines (where reflected power is dissipated). This arrangement of a continuously variable length wire antenna is one answer to the problem. It takes a bit of mechanical aptitude and a willingness to adjust the length with each frequency change, but after the initial calibration you simply adjust it to marked points. Designing a fully automatic electromechanical version is well within the skill set of many Hams...

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...

Wednesday the 17th

Wire Wrapping by Bell Telephone Laboratories

Wire Wrapping by Bell Telephone Laboratories, October 1953 Popular Science - RF CafeIf you believe this 1953 advertisement in Popular Science magazine, engineering at Bell Telephone Laboratories invented the wire-wrapping process. A little additional research shows that indeed it was a Bell Telephone engineering team led by Arthur Keller who developed the method and a wire-wrap tool to do the job. Field technician needed a fast, durable, and reliable electrical connection when making hundreds or thousands of splices at relay stations and while up on telephone poles. The key to making a good wire-wrap connection is sharp corners on the wrapping post so that the corner pushes through any oxidation or contaminant on the bare wire. NASA and the Department of Defense (DoD) have exacting workmanship standards to guarantee a rugged, durable electrical connection with low resistance, and imperviousness to contamination. In fact, properly formed wire-wrap connections are considered to be gas-tight. This same ad ran in a blitz in the October 1953 issues of Radio & Television News, Radio-Electronics and Popular Science...

Electronics Themed Comics

Electronics Themed Comics, April 1944 Radio-Craft - RF CafeHere are a couple new vintage electronics-themed comics for your enjoyment as you wind your way through the work week. They appeared in a 1944 issue of Radio−Craft magazine. My favorite is the one with the lady in the vacuum cleaner repair shop. Look at her request! Her husband must have put her up to it. The other comic is pretty good, too. Having lived toward the end of the vacuum tube era, my appreciation of the equipment is more for the nostalgic quality than memories of having to wait for the tubes to warm up and re−tuning the radio and TV set at intervals while listening and/or watching. You might want to e−mail this page link to your friends. A big list of all the posted tech-themed comics is at the bottom of this page...

Self-Eating Rocket Takes Big Bite of Space Industry

Self-Eating Rocket Takes Big Bite of Space Industry - Airplanes and Rockets"New developments on a nearly century-old concept for a 'self-eating' rocket engine capable of flight beyond the Earth's atmosphere could help the UK take a bigger bite of the space industry. University of Glasgow engineers have built and fired the first unsupported 'autophage' rocket engine which consumes parts of its own body for fuel. The design of the autophage engine - the name comes from the Latin word for 'self-eating' - has several potential advantages over conventional rocket designs. The engine works by using waste heat from combustion to sequentially melt its own plastic fuselage as it fires. The molten plastic is fed into the engine's combustion chamber as additional fuel to burn alongside its regular liquid propellants. This means that an autophage vehicle would require less propellant in onboard tanks, and the mass freed up could be allocated to payload instead. The consumption of the fuselage could also help avoid adding to the problem of space debris - discarded waste that orbits the Earth and could hamper future missions. Overall, the greater efficiency could help autophage rockets take a greater payload into space compared to a conventional rocket..."

Diagrams of the Newest Car-Radio Receivers

Diagrams of the Newest Car-Radio Receivers, June 1936 Radio-Craft - RF CafeThese 8 new schematics from a 1936 issue of Radio-Craft magazine for vintage tube-type car radios brings the total to 210 posted on RF Cafe. Included are Motorola "Golden Voice" Model, RCA Victor Model H-6, Simplex Model TA, Automatic "Magic Eye" Model A1, Arvin Model 28, Philco Model 818, Fada Model 266 Motoset, Bosch Models 736, 737, 738. The Motorla "golden Voice" model features a "magic eliminode" circuit which not only filters out automobile engine noise, but balances the noise out of the antenna lead, so that suppressorless operation is possible on almost all cars. A glance at the schematic shows that all that magic is performed by a built-in L-C filter network for the power supply, and an antenna tuning circuit. In those days, installation of a radio in a car usually required the skills of an electronics technician in order to match the antenna and fine-tune the receiver according to its environment...

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!

Tuesday the 16th

You Can't Escape Cosmic Rays

You Can't Escape Cosmic Rays, July 1948 Popular Science - RF CafeI thought beginning sentences with the word "So" was a relatively recent (and annoying) thing, but the author of this 1948 Popular Science magazine article on cosmic rays (which are actually particles) uses it at least six times. For some reason those kinds of grammatical peculiarities stand out to me when reading or listening. Other than that, Mr. Mann does a nice job presenting the basics of cosmic rays, which were a fairly newly discovered phenomenon in the day. You can tell by the large number of named PhD's researchers who were delving into the physics of cosmic rays that it was a hot topic, probably highlighted in importance because of the discovery that cosmic rays were (are) constantly bombarding every plant, animal, and mineral on Earth. Surprisingly, no mention is made of the role Einstein's special relativity theory plays with measurements made on the muons created by cosmic rays. The Muon Paradox is explained by time dilation. Concern over whether these highly energetic particles could cause cancerous mutation in living tissue was a great motivator. Fortunately, our atmosphere protects us from the majority of effects produced by cosmic rays. Astronauts...

An RF Cafe Visitor's Thoughts on AI

An RF Cafe Visitor's Thoughts on AI, Kirt's Cogitations #359 - RF CafeArtificial Intelligence (AI) has become a very controversial subject in the last few years, especially since the debut of the ChatGPT engine. "GPT" means it Generates new content using a Pre-trained database of data and Transforms it into user-requested output used on "deep learning" models. I have posted a few articles on AI topics. A couple RF Cafe visitors have chimed in with opinions on AI and whether it is more good than evil, or vise versa. One guy in particular, an ubersmart engineer living north of the border, contributed the following, which I post with permission (less identification). This was his reaction to my posting of the "ChatGPT Thinks I Discovered and Own Everything" piece... I have never been inclined to try ChatGPT, because I believe that I would get more pleasure from creating something myself than from coaxing ChatGPT into creating something I like...

Solder & Soldering

Solder & Soldering, March 1973 Popular Electronics - RF CafeRoHS (Reduction of Hazardous Substances), Pb−Free (lead−free), and other green programs were not a significant concern in the electronics industry when this article was published in the early 1970s. Instead, research and development efforts concentrated on understanding and improving the chemical and mechanical aspects of soldered electrical connections. Having "grown up" in the electronics industry during that era, most of my solder and soldering knowledge and practices still tend toward Sn−Pb (tin−lead) alloys for most applications, whether for soldering electronic components to a PCB or terminal post, soldering copper water pipes, or soldering music wire landing gear assemblies for model airplanes. Along with the rather sudden move to lead-free solder came reliability problems including "tin whiskers" and fragile interfaces, a requirement to re-design many component types to endure the higher processing temperatures required for leadless solder, and figuring out how to excuse the extra energy used and Earth-warming temperatures required to accommodate...

Major Advance Using Graphene Spintronics

Major Advance Using Graphene Spintronics - RF Cafe"Physicists at the National University of Singapore have innovated a concept to induce and directly quantify spin splitting in two-dimensional materials. By using this concept, they have experimentally achieved large tunability and a high degree of spin-polarisation in graphene. This research achievement can potentially advance the field of two-dimensional (2D) spintronics, with applications for low-power electronics. Joule heating poses a significant challenge in modern electronics, especially in devices such as personal computers and smartphones. This is an effect that occurs when the flow of electrical current passing through a material produces thermal energy, subsequently raising the material's temperature. One potential solution involves the use of spin, instead of charge, in logic circuits. These circuits can, in principle, offer low-power consumption and ultrafast speed, owing to the reduction or elimination of Joule heating..."

Short Wave Snapshots

Short Wave Snapshots, June 1935 Short Wave Craft - RF CafeHere are a few interesting photos from the annals of radio communications' 1935-era history that include airborne, land mobile, and fixed operator stations from around the world. They were published in a 1935 issue of Short Wave Craft magazine. Japanese amateur radio operator Seichiro Handa is shown sitting in his "shack" donning headphones and a Morse code key. The author mentions that judging by his high quality radio equipment, Mr. Handa's finances seemed to be unaffected by the Great Depression that hit the United States and other Western countries beginning with the stock market crash in October of 1929...

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...

Monday the 15th

Electronics News

Electronics News, June 1947 Popular Science - RF CafePopular Science magazine, as did Mechanix Illustrated and Popular Mechanics, included a wide variety of science and mechanics topics in every issue - as the titles imply. Sometimes brief news reports were used, and other time entire multi-page articles were written. In a case of the former, this collection of items appeared in the June 1947 issue. Digital computers were replacing analog computers due to their more flexible programming ability and lower inaccuracies. Data storage was easily handled with magnetic tape, but the speed of read/write operations was usually a bottleneck in the process. Radio Corporation of America (RCA) developed what they called the Selectron vacuum tube, which used phosphorous dots to store a charge representing a digital "0" or "1." Operation was somewhat akin to dynamic random access memory (DRAM) that required periodic refreshing of the storage cell value before it fades to obscurity. Before the Selectron could make it to prime time, magnetic core memories were invented. Also in the report was a method the Dutch used for hiding radios in books during World War II...

The Best Humor Is Based on Reality

The Best Humor Is Based on Reality - RF CafeWe had a strong storm run through the area last week, knocking out power for almost 24 hours. Linemen were on the job during the worst of the deluge. When we lived up north, they were out in blizzards repairing downed power lines due to winds, fallen trees and branches, and busted poles. In 2013, Congress declared April 18th as National Lineman Appreciation Day. Typical neighborhood overhead or buried lines are around 7.2 kV, and lines running out of substations can be 35 kV or more. Would you want to touch that, even with a ten-foot pole, while rain is pouring down or snow is falling? Me neither. Winter and spring are the seasons of power outages in the north, and summer and fall in the south. I'll give a shout out to the linemen now rather than on April 18th, while I'm appreciating typing this on a desktop computer in a warm house with lights, refrigerator, water heater, and everything else working.

Mac's Radio Service Shop: Looking Forward and Backward

Mac's Radio Service Shop: Looking Forward and Backward, March 1951 Radio & Television News - RF CafeWorld War II ended on September 2, 1945 following the surrenders of Japan and Germany. Almost immediately after WWII ended, the electronics market was flooded with vacuum tubes, resistors, inductors, antennas, transmission lines, meters, batteries, transformers, speakers, incandescent and neon bulbs, hookup wire, and even entire radios and test equipment. It was a good time for electronics manufacturers, hobbyists, and repair shops. In fact the U.S. government made a special effort to compensate the public for sacrifices made during the war. It didn't last long, however. The Korean War broke out on June 25, 1950, and ran through July 27, 1953. This episode of Mac's Radio Service Shop hints at the déjà vu of Mac's war years and the recurrence of leaner days settling in again.

Transistors Might Need a Different Cut of Silicon

New Transistors Might Need a Different Cut of Silicon - RF Cafe"The wafers of silicon that ultimately become the chips in your smartphone consist of a single crystal. But that crystal has many faces, and it matters which of those faces is at the surface, where transistors are made. According to research presented last month at the 2023 IEEE International Electron Device Meeting (IEDM), the industry might not be using the best crystal orientation for upcoming devices. By changing the crystal orientation, a team at IBM Research achieved as much as a doubling of the speed of positive charge through transistors, though it came at the cost of a slight slowdown for negative charge. Crystals can be reduced to a unit structure that's infinitely repeatable. For silicon, it's a cube that looks like it's got a diamond stuck inside it. There are silicon atoms at each corner of the cube as well as at the center of each face, and four more atoms within the cube's interior. Today's transistors, FinFETs mostly, are built on silicon whereby the top of that cube is the surface of the wafer. Experts call that crystal orientation '001.' Silicon wafers with the 001 orientation are used in many advanced logic technologies, including in IBM's 2-nanometer chip..."

Channel Master 6515 "Super Fringe" Radio

Channel Master Model 6515 "Super Fringe" Radio, October 1960 Electronics World - RF CafeA lot of people from the era of rooftop television antennas were/are familiar with the name Channel Master. Many of their antennas included integrated FM radio elements. Very few were likely aware that Channel Master also made radios. I don't think they ever made televisions. The fact is, companies like Channel Master did not design and manufacture their own radios and televisions; instead, they paid to have custom versions of existing products branded with their names. Sears, Roebuck's Silvertone line, Montgomery Ward's Airline products, Western Auto's Truetone line, and others are examples. This Channel Master Model 6515 "Super Fringe" transistor radio was made by Sanyo. 1960, when this ad appeared in Electronics World magazine, was the transition period between vacuum tubes and transistors. It was not uncommon to find two or more identical radios bearing different company logos. Channel Master Model 6515 "Super Fringe" radios can be found in eBay for around $30...

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 weekday. RF 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...

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    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...

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.

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

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withwave microwave devices - RF Cafe

ConductRF Phased Matched RF Cables - RF Cafe