RF Cafe Software
About RF Cafe
1996 - 2016
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 ...
All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.
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There are 1,000s of Pages Indexed on RF Cafe !
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
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2013: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
VCO Made from Graphene, TaS2 and BN 2D Materials
"This is the first useful device that exploits charge-density wave modulation of current through a 2D material, claims the University of California Riverside, which worked with the University of Georgia. Graphene can conducts electrons rapidly, but has no usable bandgap from which to forge switching behaviour. Instead of switching with graphene, a 2D crystal form material tantalum sulphide (TaS2) was ..."
Simple L and C Calculations
Although single capacitor, single inductor resonant tank circuits are not widely used, one place you do find them is in transistor amplifier stages in order to peak gain in a particular frequency band. Author Jack Najork offers here a few pointers regarding preforming quick mental calculations for how ranges of capacitance values affect the resonant frequency. For instance the ratio of capacitance values needed to cover a certain range of resonant frequencies is equal (ideally) to the square root of the frequency ratio. This comes into play both when determining values during the design phase and the selecting a variable capacitor for providing tuning ...
Congrats to June Book Drawing Winner Robert E. !
Each month I randomly select 1 or 2 people from my software purchaser list and offer to award a free book in the monthly RF Cafe Book Drawing. Also each month most people never respond to my notice of being a winner (probably thinking my e-mail notice is spam). Most of the books sell for >$100 on Amazon. This month, fortunately, Robert E., of Carlisle, Massachusetts, did respond. He wisely selected Highly Integrated Low-Power Radars, by Sergio Saponara, Maria Greco, Egidio Ragonese (graciously provided by Artech House).
Wolfspeed Announces explore RF Partnership in June Newsletter
In this issue: Wolfspeed, a Cree company that stands alone as the premier provider of the most field-tested SiC and GaN Power and RF solutions in the world, is currently sponsoring free access to Dr. Francesco Fornetti's "Conquer Radio Frequency: a Multimedia Conceptual Guide to RF & Microwave Engineering using AWR Microwave Office." This resource contains more than twelve hours of video tutorials supplemented by a reference textbook. The tutorials cover: Transmission lines, Smith Chart, S-parameters, Impedance matching with both discrete and distributed elements, Basics of amplifier design ...
Aaronia Intros Real-Time Drone and UAV Detection System
Following a four-year development program, Aaronia launched the Drone Detector, a product that exploits the RF radiation emitted by the UAV’s onboard systems and by the operator’s control unit. Two types of 3D direction-finding antenna are offered by the Drone Detector—the IsoLOG 3D 80-UWB and IsoLOG 3D 160-UWB. Both cover from 9 kHz to 6 GHz, and extenders are available should VLF (below 9 kHz) and 6-20 GHz coverage be required. The Drone Detector has a real-time bandwidth of 80 MHz. Optionally this can be extended to 175 MHz ...
RF Engineering Crossword Puzzle for July 10
Take a break and work this week's RF Engineering-themed crossword puzzle. All the words are pulled from a hand-built list of terms, names, and abbreviations that have only to do with science, mathematics, and engineering. Clues for words having to do with types of engineers are marked with an asterisk (*). If you want a crossword with names of movie stars and obscure countries, try the local newspaper ...
Come Aboard, OM! Radio Amateurs and the New Naval Reserve
Electronic warfare (EW) is a familiar term today, but in 1947 its use was a relatively new concept. As you know, great advancements in electronics occurred during the War years - from all the major Allied and Axis countries involved. Transmitters and receivers, modulation techniques, antenna designs, transmission lines, component introductions and improvements, ruggedness and portability features, reliability, serviceability, operational techniques, and other aspects of electronics benefitted from that oft-credited 'mother of invention' named 'necessity.' Along with electronic communication improvements came the need to thwart the enemy's ...
WithWave Calibration Kit Announced
Withwave's Compact Calibration Kits offers excellent performance characteristics that is specially designed for the fine-tuning in production environments and quality testing facilities using 50 ohm N-type & 3.5 mm connectors up to 6 GHz and 9 GHz, respectively. This Cal Kit includes all needed calibration standard (Open, Short, Load) in one unit that is best solution available for ease of use in VNA calibration, especially in the field ...
Please Thank everythingRF for Continued Support!
Thanks once again to the folks at everythingRF for advertising on RF Cafe! It is their support that helps deliver this website to you. everything RF is a product discovery platform for RF & Microwave Products/Services. We currently have 211,299 Products from more than 1,027 Companies across 222 Categories in our database and enable engineers to search for them using our customized parametric search tool.
Is Your Domain Being Blocked by a Country?
Recently, a company based in China contacted me about advertising on RF Cafe. After doing a lot of up-front work for them creating advertising materials, the representative informed me that he cannot access the RFCafe.com domain from his location. It is really difficult to conduct business when the customer cannot review your work, so at least for now, I am going to pass on the opportunity. The obvious question that arises from the experience is whether RFCafe.com is being blocked by China, and how do I find out? Fortunately, a few options exist with websites that will perform the check for you by pinging your URL from servers within multiple countries. Some, such as GreatFirewallOfChina.org, tests from inside China using servers in Beijing ...
Large Hadron Collider Finds 3 New Particles, Confirms 4th
"Europe's largest particle accelerator, the Large Hadron Collider, is back in action. According to two newly published studies, its latest round of experiments yielded three new 'exotic' particles and confirmed the existence of a fourth. The newly identified particles are considered 'exotic' because they contain four quarks, the building blocks of all matter. Particle physicists used to believe all particles were composed of mesons, a quark-antiquark pair, or baryons, three ..."
Ace Wire Spring & Form Company Added to Hardware Vendors Page
Mr. John Higgins, of the Ace Wire Spring & Form Company, wrote to ask that his firm be added to the Hardware Vendors page on RF Cafe. Located in McKees Rock, PA, Ace is an industry leading precision manufacturer of compression springs, extension springs, torsion springs, specialty springs, and wire forms. Free engineering design services available. Please contact them to see whether you have a need they can fill. 412-458-4830 ...
Whenever I think of springs, the goofy short film "A Case of Spring Fever" comes to mind. 'Coilie the Spring Sprite' teaches Gilbert an important life lesson after wishing for 'no more springs!'
Anatech Electronics Newsletter for July 2016
Anatech Electronics, a manufacturer of RF and microwave filters, has published its July 2016 newsletter. As always, it includes both company news and some tidbits about relevant industry happenings. This month, Sam Benzacar continues his previous discussion regarding the increasing challenge that interference is to mission-critical systems. He also reports on news about cancers risks that come with extensive cellphone use, LTE-U deployment schedules, E-Band data system advances, and using radar-based sensors to monitor and characterize patient behavior and health status. Anatech's business is to make certain that system ...
Coyne Electrical School Advertisement
June 1931 was a year and a half into the Great Depression, which began with the Wall Street crash of October 1929. It followed on the heels of the very prosperous decade known as the "Roaring Twenties," when significant, rapid advances in technology had taken place in electronics, medicine, physics, chemistry, and other fields. A huge number of radios were sold to the military, businesses, and private consumers both before stock market crash and after. A quick look at my list of Radio Service Data Sheets from the era show that to be so. In fact, it wasn't until World War II that production of new radio sets began to decrease, as all available ...
Amateur Electronic Supply Closing after 59 Years in Business
"Amateur Electronic Supply (AES) will close its doors at the end of July after 59 years in business. No reason has been given for the decision to close the business. AES has been a premier player among Amateur Radio equipment retailers for decades, as well as a major presence at Dayton Hamvention® and other events. Various media outlets were informed of the closing in a brief e-mail message on July 6, but word of the closing has not yet appeared ..."
everything RF 2016 Antenna Search Tool Available
We have recently updated the Antenna Search tool on everything RF. There are 4,000 Antennas from 48 manufacturers listed on the site. Use the search tools to find antennas by Type (Dipole, Yagi, Whip, etc.), Frequency, Gain, Industry Type (IoT, Military, SATCOM, etc.), Communications Standard (WLAN, Bluetooth, GPS, etc.), Frequency Band (UHF, L, S, C, Ka, etc.), Mounting (Pole, Magnetic, etc.) and a number of other parameters. Please let us know what you think. We are still adding more products and manufacturers ...
Graphene Based Optoelectronics Coming Soon
The mission of the Graphene Flagship is to translate graphene out of the academic laboratory, through industry and into society. This broad and ambitious aim has been at the forefront of the choices made to direct the Flagship; it focuses on real problem areas where it can make a real difference such as in Optical Communications. Optical Communications are increasingly important because they have the potential to solve one of the biggest problems of our information age: energy consumption. Almost everything we do in everyday life consumes information and all of this information is powered by energy ...
EasyEDA® Online Schematic Capture & PCB Layout
Just as the paperless office, predicted to quickly become a reality when personal computers were beginning to dominate the workplace and home in the 1980s, has yet to occur, neither has desktop software for high-end applications totally replaced online equivalents. Microsoft has made good progress in the last few years in moving part of their Office suite online, you still need a local copy of Visio, Project, and even their Visual Studio software development tools if you want to use them. Graphics and video editing software cannot be used efficiently online. The problem is mostly due to time latency between user input and software display response. Speed on the host server end is addressable with pumped up computing power and extra ...
World's Largest Radio Telescope Sets to Open in China
"The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a mega-project designed to search the cosmos for clues about our creation and whether there are any other civilizations out there. The project began development back in March of 2011. Five and a half years later, it is finally functional. The telescope, as the name would suggest, is a monstrous 500 meters in diameter, able to achieve a zenith angle of 40 degrees. The telescope ..."
Strays - Lt. Henry B. Harris Killed in Crash
You just never know when your number is going to be called. People who engage in a dangerous activity they love often claim that if they are going to die in an accident, it would preferably be while engaging in that activity. It really sucks to die like Army-Air Force Lt. Henry B Harris who was an accomplished instrument flight research pilot (and noted Ham radio operator). Rather than expiring in an airplane, he met his end as a passenger in a car that was towing some other pilot in a glider ...
New Discovery Could Better Predict How Semiconductors Weather Abuse
"Mimicking nature is not easy, but new insights by researchers at the Department of Energy's Lawrence Berkeley National Laboratory could help create a viable artificial system of photosynthesis. One of the major challenges for scientists working to create systems that efficiently convert sunlight, water and carbon dioxide into fuel is finding materials that can do the work while also surviving the corrosive conditions that are part of the process ..."
Skyworks Expands Antenna Tuning Portfolio
Skyworks Solutions, an innovator of high performance analog semiconductors connecting people, places and things, today expanded its best-in-class antenna tuning product portfolio with the addition of several new high performance solutions. Skyworks' latest antenna tuning offerings address the design challenges mobile device manufacturers face as smartphones become thinner, leverage revolutionary case materials and integrate more cellular bands. By optimizing radiated efficiency, Skyworks' antenna aperture tuners enable higher data throughput and smaller footprints, minimizing dropped calls and improving the consumer experience. 'Cellular band proliferation in smartphones ..."
The Switch That Could Double USB Memory
"Conventional USB flash drives are electronic data storage devices. They store information by using millions of small gates that process information into 'words' consisting of various combinations of the numbers 0 and 1. A team of scientists at Hokkaido University’s Research Institute for Electronic Science investigated the possibility of using a magnetic signal along with the electronic signal to allow double the storage capacity in these 'multiplex writing / reading' devices. In addition to the binary ..."
The "Twin-Lamp" - The Poor Man's Standing-Wave Indicator
Even if you have no use for building a "twin lamp" standing wave indicator for a twin lead transmission line (solid or open ladder type), this article makes an interesting read for its theoretical description of how the device works based on current phases in the circuit. A pair of flashlight bulbs and couple feet of wire is all that is needed. When operating properly, the "twin lamp" indicator indicates by virtue of whether one or both bulbs are illuminated whether there is a significant standing wave present on the line. Author Charles Wright warns that the VSWR level cannot be reliably determined based on relative brightnesses of the two bulbs; it is meant for use as a best case ...
Bi-Directional Silicon Carbide Planar Insulated-Gate Bipolar Transistor
"Rensselaer Polytechnic Institute and General Electric Global Research Center in the USA 'experimentally demonstrate, for the first time, bi-directional 4H-silicon carbide planar gate, insulated-gate bipolar transistors (IGBTs) fabricated on 250μm-thick, lightly doped free-standing substrates.' The researchers see potential for their bi-directional (BD) IGBTs as switches that can control current in both directions with application in matrix or neutral point piloted multi-level converters. Compared with multi-component implementations ..."
Notable Tech Quote: Crow T. Robot
"Just because it's futuristic doesn't mean it's practical." - Crow T. Robot, MST3K, 'Design for Dreaming,' Mystery Science Theater 3000 (MST3K). MST3K was a TV series in the 1980s-1990s where a human was forced by evil scentists to watch B movies, with automatons Crow T. Robot and Mike Servo provided for comfort. Their silhouettes are seen in the theater's front row as they make wise cracks about and gestures toward the movie as it plays. One of my favorite clips is from the "Space Mutiny" film, where Crow, Mike, and Servo roll out a long string of insulting names for the 'hero' character. You'll definitely get a laugh out of it.
Electron-Microscopy Measures Magnetism at Atomic Scale
"Researchers at the Oak Ridge National Laboratory in the U.S. and Uppsala University in Sweden have developed a new electron-microscopy technique that can detect magnetism at the atomic scale. The technique exploits distortions - or "aberrations" - in how the microscope's electron beam is focused, and could be used could be used to study magnetic domains in devices such as computer hard-disk drives. Electron microscopes focus beams of electrons in much the same way that optical microscopes ..."
Engineering Career and Job Hunting Advice for July 5, 2016
Summer has traditionally not been the best time to be job hunting in industries where project budgets begin and end on the calendar year, but I these days there probably are no discernable rules. A lot of advice has been written regarding what to do and what not to do during job hunting and during the first months of employment. As with technology, the list of do's and don'ts regarding all aspects of a career change over time. Workers today need to know about how to exploit and/or avoid social media, how to handle interviews within the constraints ...
Resonating Drums Made Out of Graphene Might Make Better Sensors
"Researchers at Cornell University have fabricated graphene membranes into micrometer-scale drums that can be stimulated by a voltage to transfer one type of mechanical vibration into another. The researchers believe this capability can lead to new applications in telecommunications where graphene-based mechanical resonators could be used as frequency mixers, which are often used, for example, to modulate carrier waves with signals ..."
The Pied Piper of Hamelin
This might be my oldest copy of QST, being Vol. XIII, Number 6 (December 1915 was the first issue). Up until a few decades ago, authors commonly appropriated themes and characters from familiar fairy tales and fables for use in articles of instructional nature. Some publications even used comic book style formats for teaching to beginners. The term 'wabbulation' (aka 'wobbulation') is spoken to Uncle Jimmy by the fabled Piper, and I have to admit not being familiar with the term. According to W2PA's story, 1920s era QST technical editor Robert Kruse coined the word to describe inadvertent modulation ...
Radio Service Data Sheets for Fada and Colonial Superheterodyne Receivers
The 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 RADIOCRAFT until the expiration of their subscriptions."
Tim O.'s Crosley 03CB Console Radio
A few days ago, Mr. Tim O. sent me photos of the Crosley model 03CB console (floor) radio that his mother owns and which he remembers listening to as a kid. Tim says as far as he knows the radio still works. As can be seen in the images below, it is still in pretty good condition for a 75-year-old radio! I noticed that both the volume and tuning knobs appear to be a bit melted, which must have been a common occurrence in this model because the Crosley 03CB radio that I recently bought and restored also had melted volume and tuning knobs. The metal chassis ...
Radar & Radio Crossword Puzzle for July 3, 2016
For the sake of avid cruciverbalists amongst us, each week I create a new crossword puzzle that has a theme related to engineering, mathematics, chemistry, physics, and other technical words. This one has extra words pertaining to radar and radio. You will never be asked the name of a movie star unless he/she was involved in a technical endeavor (e.g., Hedy Lamar). Enjoy!
Free Engineering Magazine Subscriptions!
The free whitepapers, pamphlets, books, magazines, and chapter examples listed here are a small sample of a lot of new items that are offered for FREE through TradePub. The publishers make them available to qualifying people as a promotional campaign for their full line of offerings. Note: I earn a few pennies (literally) when you download one of these or the many other pubs available, so please help yourself.
Wi-Fi Alliance Expands WiFi 802.11ac for Wave 2
"The Wi-Fi Alliance this week announced its expanded Wi-Fi Certified ac to include new features that provide a better experience. The new features in 802.11ac Wave 2 should provide operators and their end users with big improvements in the user experience. One of the most talked about features – multi-user multiple input multiple output (MU-MIMO) - allows more devices to operate simultaneously on the same network. The ability for a single access ..."
Radar Tames the Wild Blue Yonder
The VOLSCAN (Volume Scanning) radar system was a paradigm changer for air traffic controllers charges with guiding aircraft while assuring safe separation. Busy terminal areas were a particularly difficult challenge due to the large variation in aircraft speeds and types. VOLSCAN was a computer that tracked the position, direction, and speed of each target and even made recommendations to controllers for course assignments. It also warned of impending dangerous scenarios. Another VOLSCAN article in the July 1954 issue of Radio-Electronics went ...