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Homepage Archive - July 2018 (page 3)

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.

Homepage Archive Pages

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

See Page 1 | 2 | 3 of the July 2018 homepage archives.


Tuesday 31

Lens-Like Antenna: Low Noise, Less Space

Lens-Like Antenna: Low Noise, Less Space, February 28, 1964 Electronics Magazine - RF CafeThis is the first article I have posted from a magazine called, simply, Electronics. It is very different from all the other vintage electronics magazines I have used in the past. Electronics is much more focused on military, space, and fundamental research. New issues were published bi-weekly by McGraw−Hill from 1930 until 1988. About half the editions (this is not one of them) had two to three times as many pages as the other half, with most of the extra pages being advertisements. The publishers must have made a fortune on advertising revenue. My guess is that the vast majority of the companies appearing in the early 1960s issues I bought on eBay do not exist anymore, having either gone out of business or having been acquired by bigger ...

Promote Your Company on RF Cafe for as Little as $35/Month

Sponsor RF Cafe for as Little as $35 per Month - RF CafeRF Cafe typically receives 10,000-15,000 website visits each weekday and about half that on weekends. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 7,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. New content is added on a daily basis. Items added on the homepage are broadcast on LinkedIn, Facebook, and Twitter. Banner advertising begins at $150/month ...

FCC Compliance for Human Exposure to RF Electromagnetic Fields

Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields - RF CafeRF Cafe website visitor David Burger (VK2CZ / K3HZ) sent me a great Excel spreadsheet titled, "Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields." As amateur radio operators learn when studying to earn a license, you are required to perform a calculation to verify that the transmitted effective power radiating from your antenna does not exceed a specified maximum value in areas where humans have access. David's spreadsheet takes system parameter inputs and calculates, along with various other values, the minimum required separation distance for both controlled and uncontrolled human access. If your antenna is mounted up higher than the limit distance, then no action is required to keep people away. Otherwise, you must either erect physical barriers or reduce power output to comply with the maximum RF exposure limit ...

QuinStar Sets New Benchmarks for SSPAs Operating Above 100 GHz

QuinStar Sets New Benchmarks for SSPAs Operating Above 100 GHz - RF CafeQuinStar has established new power benchmarks for SSPAs operating at frequencies above 100 GHz. We have successfully demonstrated two GaN MMIC amplifiers operating at F-band frequencies: The first producing an output power of 28-29 dBm from 102 to 118 GHz, while the second, a wideband design, delivering an output power of greater than 25 dBm from 98 to 122 GHz. Lastly, we have assembled and tested a multi-MMIC SSPA producing an output power of 2-3 W over the 102–116 GHz band. These findings were presented at IMS 2018. This paper reports the design and performance of two new GaN MMIC amplifiers operating at F-band frequencies ...

New Bell Telephone

New Bell Telephone, February 1953 Radio-Electronics - RF CafeSomeone sent me a link to a viral video of a group of teenagers (aka "Millennials") attempting to use an old school dial type telephone. Two things are notable. #1: They do not remove the handset from the cradle prior to dialing. #2: One of them asks whether it is necessary to let the dial spin all the way back to rest before dialing the next number. It's really not their fault since except for in dusty old places like my house, finding a dial phone is difficult. Many historians have commented that two innovations most responsible for America's greatness in the last century were the interstate highway system (for moving goods) and the telephone system. Bell Telephone Labs engineers designed phones and all the equipment that connected them to be simple, highly functional, robust, and to have ...

FSK Turbo Codes Supercharge Internet of Things

FSK Turbo Codes Supercharge Internet of Things - RF Cafe"Leti's Turbo-FSK is a low-power, long-range solution for IoT. Internet of Things networks are different beasts than traditional communication networks. Many, though not all, IoT networks are characterized by devices that communicate very little for most of the time, only to burst into action when they need to send - or receive - a relatively large amount of data in a very short amount of time. That's why researchers at Leti, the Laboratoire d'électronique des technologies de l'information in Grenoble, France, developed a new modulation scheme to improve IoT communication. What's more, they have developed a system ..."

Monday 30

Frequency-to-Meter Conversion Chart for Hams & SWL's

Frequency-to-Meter Conversion Chart for Hams & SWL's, June 1966 Popular Electronics - RF CafeAs with your school and college days where once there was no longer any reason to memorize physical constants, conversion formulas, and names of people, places, and things, much of the noggin's gray matter was repurposed to remember topics of more immediate need. You can always look up what you have forgotten. While studying for your Ham radio or FCC license, being able to be able to quickly convert between wavelength and frequency is essential. Recalling on demand frequency-wavelength pairs is a real time saver on a timed exam. Even being able to perform the conversion on a calculator during the test takes up valuable time that could be better used on other tasks. This handy-dandy chart for converting ...

RF Front End Module Market to Show Promising Growth up to 2023

RF Front End Module Market to Show Promising Growth up to 2023 - RF Cafe"According to a recent report published by Yole Développement, the RF front-end module market is expected to reach US $35.2B by 2023. The Yole Group of Companies including KnowMade, System Plus Consulting and Yole, combined their expertise to work on a comprehensive analysis of the RF front-end module industry. They have mixed their knowledge of the RF FE ecosystem, their understanding of the IP landscape and their analysis of the today's RF technologies to detail the industry evolution and highlight the technology trends. Yole Group of Companies has created a set of four reports dedicated to the RF FE sector. The RF FE modules market, along with the WiFi connectivity sector, will show an impressive 14% CAGR between 2017 and 2023 ..."

Empower RF Systems to Hold 1 kW Live Demo at EMC Symposium 2018

Empower RF Systems to Hold 1 kW Live Demo at EMC Symposium 2018- RF CafeEmpower RF Systems is once again conducting live demonstrations of broadband, high power amplifiers with compelling performance, industry leading small size, IOT interface, and user selectable functionality that dares to challenge legacy products offered in the market. Next appearing at EMC+SIPI 2018 at the Long Beach Convention Center, we will be showcasing one of our popular models, the 2170, operating from 1 to 3 GHz at 1 kW in a 5U chassis. The 2170 is a member of Empower’s Next Gen family of high power amplifiers that is the result of a visionary design combining advances in RF components, digital loop control, real time software, HTML GUI, thermal, and electro mechanical design ...

B&K Manufacturing Co. Advertisement

B & K Manufacturing Co. Advertisement, April 1960 Electronics World - RF CafeUntil solid state electronics had supplanted the majority of vacuum tube type televisions and radios, portable tube testers were essential equipment to successful, efficient troubleshooting and repair in businesses and people's homes. Yep, believe it or not the stories told about doctors and electronics repairmen visiting homes are not just fables. I remember as recently as the 1960s having our family doctor make house calls when I or one of my fours sisters got sick. Both doctors and TV servicemen ceased the practice at about the same time - probably the result of a Brotherhood of Electronics Technicians and General Practitioners collective bargaining agreement ;-) Many column inches of editorials, articles, comics, and letters to the editor were devoted to the trials and tribulations of in-home servicemen and the experiences ...

SpaceX's 2nd Launch in 3 Days Lofts 10 More Iridium Satellites

SpaceX's 2nd Launch in 3 Days Lofts 10 More Iridium Satellites - RF Cafe"Firing through a veil of fog blanketing California's Central Coast, a Falcon 9 launcher climbed into orbit Wednesday with 10 more satellites for Iridium's voice and data relay constellation, pushing the upgraded network closer to completion as SpaceX accomplished another landing of the rocket's first stage booster. The 229-foot-tall launcher lit its nine Merlin main engines after a problem-free countdown and lifted off from Space Launch Complex 4-East at Vandenberg Air Force Base at 4:39:30 a.m. PDT. Riding 1.7M pounds of thrust, the slender, two-stage launcher turned southward from Vandenberg ..."

Sunday 29

Engineering Crossword Puzzle w/Weekly Headlines July 29

RF Cafe Engineering Crossword Puzzle w/Weekly Headlines July 29, 2018 - RF CafeFor the sake of all the avid cruciverbalists amongst us, each week I create a new technology-themed crossword puzzle using only words from my custom-created list related to engineering, science, mathematics, chemistry, physics, astronomy, etc. At least 10 clues with an asterisk (*) in this puzzle are pulled from the past week's "Tech Industry Headlines" column on the RF Cafe homepage. You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, see someone or something in the exclusion list directly related to this puzzle's theme, such as Hedy Lamar or the Bikini Atoll, respectively. Enjoy! ...

Friday 27

International Electronics Quiz

International Electronics Quiz, July 1967 Popular Electronics - RF CafeTest your knowledge of the country of origin of the inventors responsible for these ten inventions. In some cases the inventor was born in another country but then emigrated to the U.S. or another country before his/her invention or discovery. This is a pretty tough quiz even for someone who has done a lot of reading on the history of technology. Guessing the country of origin for the inventor of the voltaic pile might be easier if you recall the guy's name (hint: his name is in the caption), and for the TV antenna take note of the configuration of the elements (hint: there was nobody named Log Periodic). I'm too embarrassed to divulge my score, but if you do better 50% or better, you've beaten me ...

World's Fastest Human-Made Spinning Object Created

World's Fastest Human-Made Spinning Object Could Help Study Quantum Mechanics - RF Cafe"Researchers have created the fastest human-made spinning object in the world, which they believe will help them study material science, quantum mechanics and the properties of vacuum. At more than 60 billion revolutions per minute, this machine is more than 100,000 times faster than a high-speed dental drill. 'This study has many applications, including material science,' said Tongcang Li, an assistant professor of physics and astronomy, and electrical and computer engineering, at Purdue University. 'We can study the extreme conditions different materials can survive in.' Li's team synthesized a tiny dumbbell ..."

Symbolism in the FCC Seal

Symbolism in the FCC Seal (Dave Casler) - RF CafeDave Casler, KE0OG, has a YouTube channel titled, "Ham Radio Answers" where, as the name implies, he fields questions from viewers. This Symbolism in the FCC Seal episode was featured in the August 2018 issue of QST magazine. As one who explores the history of radio communications and electronics, I found this interesting. Et tu?

Electronics-Themed Comic, February 1972 Popular Electronics

Electronics-Themed Comic, February 1972 Popular Electronics - RF CafeThis is a great electronics-themed comic from a February 1972 issue of Popular Electronics. It encompasses the essence of the stereotypical salesman ruse, especially in that era when people were sure that electronics repair services were out to rip them off by selling unneeded services and replacement parts. Aspiring TV technicians who couldn't grasp the technology moved on to working as mechanics in a garage, poking tiny holes in brake lines to scare owners into paying for complete braking system rebuilds. I usually like to post multiple comics on each page, but at the moment only this one is available ...

RF Stencils for Visio v3.1 Available! - Your Support Keeps Me off Welfare ;-)

RF Microwave Wireless Analog Block Diagrams Stencils Shapes for Visio - v3 - RF Cafe

With more than 780 custom-built symbols, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every object has been built from scratch to fit proportionally on the provided A- and B-size drawing page templates (you can use your own page if preferred). Components are provided for equipment racks (EIA and ETSI) and test equipment, system block diagrams and conceptual drawings, and for schematics ...

Electronic Stickers to Streamline Large-Scale IoT

Electronic Stickers to Streamline Large-Scale IoT - RF Cafe"Researchers have developed a new fabrication method that makes tiny, thin-film electronic circuits peelable from a surface. The technique not only eliminates several manufacturing steps and the associated costs, but also allows any object to sense its environment or be controlled through the application of a high-tech sticker. Billions of objects ranging from smartphones and watches to buildings, machine parts and medical devices have become wireless sensors of their environments, expanding a network called the 'internet of things.' As society moves toward connecting all objects to the internet - even furniture and office supplies ..."

Thursday 26

Spot News - Electronic Industry News

Spot News - Electronic Industry News, April 1960 Electronics World - RF CafeTelevision broadcast stations were quickly growing in number in the post-Korean War era and the FCC needed to devise a scheme for accommodating more channels. There were only 13 channels (only 2-13 used) allocated in the VHF spectrum with 6 MHz-wide bands. Even though VHF propagates primarily in a line-of-sight mode, reflections and earth-bounce can extend the range fairly significantly, limiting density in closely spaced cities. The military refused to yield any spectrum so a decision was made to add new channels (14-83, also 6 MHz wide) in the UHF band. UHF presented its own problems with more difficult equipment manufacturing issues and higher atmospheric attenuation. It never really caught on because cable TV was being widely installed in metro areas ...

Global OTA Testing Market to Reach $3 Billion in Revenue by 2025

Global Over-the-Air (OTA) Testing Market to Reach $3 Billion in Revenue by 2025 - RF Cafe"The global over-the-air testing industry is projected to reach $3B in revenues by 2025, growing at a CAGR of 9.4% from 2018 to 2025. This industry was valued at $1.5B in 2017. At present, North America dominates the global OTA testing market with a revenue of $630.5M in 2017, and is projected to reach $1.2B by 2025, growing at a CAGR of 8.7% from 2018 to 2024. However, the Asia-Pacific region is anticipated to exhibit the highest CAGR of 11.7% during the forecast period. Over the Air (OTA) testing is a mandatory test to get the cellular telecommunications and internet association (CTIA) certification ..."

ConductRF Low PIM RF Cables for DAS and Cellular

ConductRF Low PIM DAS and Cellular RF Cables- RF CafeConductRF provides 3 styles of solution for DAS applications in Stadiums, Malls, Campuses, Hotels and more. Straight & R/A Low PIM Connectors are available for 7/16, N, SMA, QMA, 4.1/9.5 and 4.3/10 interfaces. We also offer Low PIM Adapters and PIM Test Cables for all these series. Utilizing ConductRF's new Low PIM Direct Solder Attachment Connectors, we provide high performance solutions for Low PIM interconnect including Straight, Right Angle, Bulkhead and Panel attachment. Performance better than −155 dBc is validated through 100% testing ...

The Ubiquitous Ham

The Ubiquitous Ham, June 1966 Popular Electronics - RF CafeYou probably need to be a Ham radio operator to fully appreciate the humor in some of these comics. The first one, for instance, is a poke at a guy proudly pointing out his QSL cards from distant (DX) stations "right near the city limits," "on the other side of town," etc., basically what you can pull in with a home Citizens Band (CB) radio base station and a rooftop antenna. In another, the "73" signoff code is from the Western Union telegraph standard meaning "Best regards." "88" means "Love and kisses," hence the guy's unnerved response. The others don't really require an insider viewpoint. Let me know if you need any more help ;-) ...

RF Test Technician Needed by Empower RF Systems

RF Test Technician Needed by Empower RF Systems - RF CafeJob Opportunities - RF CafeEmpower RF Systems is a leading provider of high-power ultra-broadband radio frequency (RF) amplifier solutions. The company and designs and manufactures solid-state, high-power RF amplifier systems and modules for commercial, scientific, and military customers worldwide. RF Test Technician Position Summary: Reporting to the Production Test Manager and partnering closely with engineering teams, the RF Test Technician is responsible for developing and performing test solutions for RF products from concept through manufacturing release. He/she supports product development evaluations and final product characterization testing, and works with the development team to provide testability planning, strategies and methodologies ...

A Photonic Circuit for Quantum Computers

A Photonic Circuit for Quantum Computers - RF Cafe"Getting photons to interact is a key step toward using them as qubits. The foundational element of quantum computers is the qubit. Qubits can be any kind of particle that has quantum properties, such as an electron or a photon. For these qubits to accomplish their job in a quantum computer, they need to interact with each other in a quantum process known as entanglement. While photons would make for great qubits because of their speed, they don't like to interact with each other, or anything else for that matter, making it difficult to achieve quantum entanglement. Now researchers at the University of Maryland and the Joint Quantum Institute have managed ..."

Wednesday 25

Electricity from Atoms

Electricity from Atoms, February 1953 Radio-Electronics - RF CafeDr. Linder's patented AC and DC generators exploited alpha (proton) and beta (electron) particle emissions from radioisotopes contained within. The device is basically a metallic sphere concentric to an enclosed mounting platform for polonium (α particle emitter), phosphorous (β particle emitter), or similar elements. With just a gram of radioactive material, the charge which accumulates on the outer sphere generates a very high voltage (~1 MV) driving a low current (~1 mA). Georg Ohm's work tells us that is equivalent to 1 kW of power - quite a lot for a fairly compact device. Dr. Linder envisioned multiple atomic generators combined in series and/or parallel to obtain the required power. No mention was made of the effective internal resistance, which would ultimately determine the terminal voltage when connected to a load ...

RF Cascade Workbook 2018 - Your Support Helps Keep Me off Welfare ;-)

RF Cascade Workbook 2018 Is Available Now! - RF Cafe
RF Cascade Workbook 2018 is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. 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 ...

everythingRF Adds 6 New Component Search Categories

everythingRF Adds 6 New Component Search Categories - RF CafeeverythingRF has created the largest database of searchable RF and microwave components, equipment and services. everythingRF has recently added six (6) new categories to their parametric search tool: DRO's, PL-DRO's, VCSO's, SAW Resonators, DLVA's, and Pick-Off Tees . The parametric search tool makes it easy to find products across multiple manufacturers based on the user's requirement. For example, the user can enter the frequency, voltage and other parameters and the tool scans multiple manufacturer catalogs to find the product ...

Flat-Screen TV Has 52,900 Picture Elements

Flat-Screen TV Has 52,900 Picture Elements, June 1969 Radio-Electronics - RF CafeA 720-line HDTV display is made up of 1,280 vertical lines and 720 horizontal lines of pixels, which gives a total of 921,600 pixels. A 1080-line HDTV has 1,920 vertical lines and 1,080 horizontal lines, for a total of 2,073,600 pixels. In 1969, a 230 vertical line by 230 horizontal line electroluminescent (EL) flat-screen television display with 52,900 pseudo-pixels was considered a big deal - and it was since it was the starting point for digital flat-screens of today. Interestingly, while the "pixel" distribution was square, the actual display retained the standard 4:3 aspect ratio, meaning horizontal element width was 33% greater than the vertical element. Since each EL element was addressed individually, there was no ability of a picture element to be shared by adjacent "pixels," so displaying a circle would result in a very pixelated picture ...

Thanks to BBTLine for Continued Support!

BBTLine - BroadBand Transmission Line Products - RF CafeBBTLine offers a unique patented combiner / splitter design that allows for more compact devices while maintaining low insertion loss, excellent return loss and excellent amplitude/phase balance. These are not standard Wilkinson-style RF splitters. 2-, 4-, and 8-way, broadband 0.5 - 6 GHz, low loss (0.7 dB @ 6 GHz), excellent amplitude / θ balance (±0.1 dB, ±1°), surface mount & connectorized. Please visit BBTLine today to see how they can help your project ...

Nanoparticles Enable Molecular Electronic Devices

Nanoparticles Enable Molecular Electronic Devices - RF Cafe"Last week, researchers at IBM Research-Zurich in Switzerland, and the Universities of Basel and Zürich announced in a Letter published in Nature a new method for creating electrical contacts to individual molecules on a silicon chip. The advance could open up a promising new way to develop sensors and possibly other electronic or photonic applications of manipulating single molecules. When, in the mid-1970s, researchers discovered single molecules with interesting electronic properties such as that of a diode, hopes were high that this would spur the development of a new semiconductor technology that might compete with silicon-based electronics ..."

Tuesday 24

Molecular Electronics

Molecular Electronics, April 1960 Electronics World - RF Cafe"Eventually," Dr. Herwald said, "we believe it will even be possible to automatically and continuously produce actual electronic equipment, such as radio receivers and amplifiers, starting from a pool of molten semiconductor materials." That was in early 1960 in an Electronics World article titled, "Molecular Electronics." The term "molecular" references what eventually became integrated circuits (IC), the first of which was realized in 1958 by Texas Instruments engineer Jack Kilby. Kilby's IC incorporated one transistor, one capacitor, and three resistors on a germanium substrate. Building on that success, researchers envisioned single-chip semiconductors which contained hundreds, thousands, and even millions of transistors, diodes ...

Space, Not Brexit, Is Final Frontier for Scottish Outpost

Space, Not Brexit, Is Final Frontier for Scottish Outpost - RF Cafe"Never mind Brexit: For a remote peninsula in the Scottish highlands, the buzz is all about hi-tech rocket launchers firing satellites into space. In just three years' time, rockets will send satellites into orbit from the rugged stretch of coastline, under British government plans unveiled this week. The sleepy county of Caithness and Sutherland has been selected as the site of the country's first ever space port, Britain announced at the Farnborough Airshow, a showpiece event for the global aerospace sector ..."

EDI CON USA 2018 Announces EDI CON University

EDI CON USA 2018 Announces EDI CON University - RF CafeElectronic Design Innovation Conference and Exhibition (EDI CON) USA, the industry event that brings together RF/microwave and high-speed digital design engineers and system integrators, is pleased to introduce its EDI CON University 2018 program at its event this October 17 and 18 at the Santa Clara Convention Center. These 2-hour sessions offer in-depth training in a particular topic, such as MIMO Test, Amplifier Design, and Measuring Impedance. All conference pass holders are eligible to attend, but pre-registration happens during the registration process. After attending an EDI CON University course, attendees can earn IEEE Continuing Education Unit/Personal Development Hour ...

Comes the Revolution - or - "40 Million Frenchmen Can't Be Wrong"

Comes the Revolution or "40 Million Frenchmen Can't Be Wrong", May 1966 Popular Electronics - RF CafePopular Electronics printed in April 1966 its first notice of new frequency units to be used beginning with the June edition. The May issue included this Old World Standards Breaking Through - Reader Response, June 1966 Popular Electronics - RF Cafepiece titled, "Comes the Revolution - or - '40 Million Frenchmen Can't Be Wrong'." Predictably, not everyone liked it. With the June issue came the promised change and along with it the first in a series of reader responses. I also found a reader's opinion from the August issue as well. Evidently, not everyone wanted to honor Heinrich Hertz by naming the base unit of frequency in his honor ...

Installing an Android Radio and GPS into an Old Honda

Installing an Android Radio and GPS into an Old Honda - RF CafePaul Rako, over at Electronic Design, has posted many pieces over the years about his DIY projects. This one details his exploits while retrofitting his 1992 Honda Accord with an Android radio and GPS. The finished product look like a factory-installed option. "Like a lot of engineers, I enjoy working on my own cars. I take pride in keeping my old 1992 Honda Accord running. I have replaced a bad ignition module inside the distributor, and the cracked radiator. I did take it to a mechanic to replace the axle half-shafts, but try to do all the lighter work myself. Lately that has included fixing a broken key lock on the passenger side, as well replacing the lug nuts so that ..."

China Plans 2 New Gravitational-Wave Missions

China Plans 2 New Gravitational-Wave Missions - RF CafeThis is worth looking at just for the cool image. "China has revealed plans for two space-based missions to study gravitational waves. The National Space Science Center, Chinese Academy of Sciences (CAS), announced on 4 July that the country will launch a mission in 2020 to monitor gamma-ray bursts associated with gravitational-wave events. The CAS also gave the go-ahead for a fully-fledged gravitational-wave detector to be sent into space in 2033. Gravitational waves are distortions of space-time that occur when massive bodies, such as black holes, are accelerated. Since their first direct detection in 2015 by the Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors ..."

Monday 23

Electrical Shock: Fact and Fiction

Electrical Shock: Fact and Fiction, May 1959 Electronics World - RF Cafe"The Far Side" Doctors Poke Brain - RF CafeAny time I see an article that references causing limb movements by poking the brain with electrical signals, I think of the old The Far Side comic. Artist Gary Larson drew quite a few hilarious operating room scenarios. Electrocution is of course not a laughing matter - unless it happens to someone else and it is not serious and no harm is done. Then - and only then - can it be funny. I've laughed at myself many times after receiving a good jolt due to stupidity. Sometimes after such an experience I wonder how I never killed myself from getting zapped as the result of being too lazy to turn off a circuit breaker before servicing a light switch or receptacle. The sad thing is that I'll probably do it again some day ...

25 Charts on Spectrum Ownership in the United States

25 Charts on Spectrum Ownership in the United States - RF Cafe"Licensed spectrum remains the lifeblood of the cellular industry. But which companies actually own all those spectrum licenses? More importantly, which spectrum licenses do they own, how much did they pay for them, and where is the market heading? This report aims to answer these questions. We've collected the below charts from a variety of sources including spectrum management companies, Wall Street analyst firms and boutique analysis companies such as Allnet Insights & Analytics. Our goal is to provide an overview of licensed spectrum ownership in the United States ranging from low-band licenses like 600 MHz to high-band holdings up to 40 GHz ..."

Foreign Tube Substitution Data

Foreign Tube Substitution Data, May 1959 Electronics World - RF CafeI suppose a more appropriate title for this chart would be "Foreign Valve Substitution Data," considering that most (if not all) of Europeans refer(red) to vacuum tubes as "valves." As with having posted scores of Radio Service Data Sheet pages for the benefit of hobbyists who restore and service vintage radio equipment, I also post other hard-to-find reference resources when I find them. Sure, the number of people looking for this information is extremely small, but they are extremely grateful for this when in the throes of finding replacement tubes (valves). Posting a hyperlink to this page on the RF Cafe homepage will assure that ...

Corner Press QSL Card Printing Services

Corner Press QSL Card Printing Services - RF CafeBarry Rimer (WA2WAO), proprietor of Corner Press, has been printing QSL cards since 1961. QSL cards are cards Amateur Radio Operators (HAMS) send to each other to confirm a QSO (talking to each other on the air). QSL's were our first product; it's how we started in 1961. In 1971 we changed the company name to Corner Press to reflect a more diverse product line, not just HAM radio specific. There are more than 70 standard designs to choose from, or submit your own custom design. We produce QSL's in many styles: Flat printed in one or two spot colors, Raised printed in one or two spot colors, Full bleed full color. Please contact Barry for your QSO printing needs ...

Experts and Engineers Explain 10 Steps of Design Process

Experts and Engineers Explain the 10 Steps of the Engineering Design Process - RF Cafe"The 10 steps of the engineering design process are fundamental knowledge for all budding engineers. If you're hoping to become an engineer, one of the most crucial things you need to learn are the 10 steps of the engineering design process. This process lays out the correct protocol for any project, allowing everything to go seamlessly. No matter which area of engineering you intend to work in, the 10 steps will always be important. They're a fundamental part of engineering, and can always provide a solid foundation for your work. Let's take a look at each step, and hear what the experts have to say about the importance of the process ..."

Sunday 22

Engineering Crossword Puzzle w/Weekly Headlines, July 22

RF Cafe Engineering Crossword Puzzle w/Weekly Headlines July 22, 2018At least 10 clues with an asterisk (*) in this technology-themed crossword puzzle are pulled from this past week's (7/16 - 7/20) "Tech Industry Headlines" column on the RF Cafe homepage. For the sake of all the avid cruciverbalists amongst us, each week I create a new technology-themed crossword puzzle using only words from my custom-created list related to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, see someone or something in the exclusion list who or that is directly related to this puzzle's theme, such as Hedy Lamar or the Bikini Atoll ...

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About RF Cafe
Kirt Blattenberger - RF Cafe Webmaster
Copyright: 1996 - 2018
Webmaster:
    Kirt Blattenberger,
    BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

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