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Homepage Archive - May 2019 (page 4)
See Page 1 | 2 | 3 | 4 | 5 of the May 2019 homepage archives.

Friday 23

More Experiments in Electroculture

More Experiments in Electroculture, June 1971 Popular Electronics - RF CafeExploiting the electronic nature of living organisms through contrived application and manipulation of electric currents has been a goal of researchers (and quacks) ever since Luigi Galvani first discovered that connecting a battery lead to a frog's leg would cause it to kick. Psychogavanic reflex (PGR) is the technical term for the science. Once it was determined that all forms of fauna would respond to electrical stimulation, it wasn't long before the same sort of treatment was applied to all forms of flora. Many people (not me, for the record*) believe that talking to plants can influence their health and growth, so why not - so goes the reasoning - try electric currents as well. We all know from spy, war, sci-fi, and horror movies that under the right conditions...

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. Sam Benzacar's monthly newsletters address contemporary wireless subjects. Please visit Anatech today to see how they can help your project succeed...

"Ravin" - an Electronics-Themed Poem

Electronics Poetry - "Ravin", September 1942 QST - RF CafeThis is yet another example of humorous - and clever - poetry written by Hams from back in the 1940s... November 1942, to be exact. It appeared in the ARRL magazine QST. As alluded to in the title, "Ravin," it is a play on Edgar Allen Poe's famous "The Raven" poem. A few other electronic-themed poems are listed on the page as well, discovered in QST and in Popular Electronics. Enjoy...

Many Thanks for Alliance Test Equipment's Support!

Allied Test Equipment Products - RF CafeAlliance Test 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. Please visit Allied Test Equipment today to see how they can help your project...

Anokiwave Names Alastair Upton Chief Strategy Officer

Anokiwave Inc. Names Alastair Upton Chief Strategy Officer - RF CafePersonal note: Alastair is one of the nicest guys you'll ever work with. "Anokiwave, an innovative company providing highly integrated IC solutions for millimeter-wave (mmW) markets and Active Antenna based solutions, today announced the latest addition to its executive leadership team with the appointment of Alastair Upton to the position of Chief Strategy Officer, a new position within Anokiwave, effective May 2019. Mr. Upton will report directly to Chief Executive Officer, Robert Donahue. As the Anokiwave CSO, Alastair will be responsible for developing and executing Anokiwave's business strategy in all key markets, including responsibility for the strategic marketing organization, driving the company product roadmaps, and managing partnership programs..."

Tug-of-War Drives Magnetic North Sprint

Tug-of-War Drives Magnetic North Sprint - RF Cafe"As far as we know, Earth's magnetic north has always wandered, but it has recently gained new momentum and is making a dash towards Siberia at a pace not seen before. While this has some practical implications, scientists believe that this sprint is being caused by tussling magnetic blobs deep below our feet. Unlike our geographic North Pole, which is in a fixed location, magnetic north wanders. This has been known since it was first measured in 1831, and subsequently mapped drifting slowly from the Canadian Arctic towards Siberia. One of the practical consequences of this is that the World Magnetic Model has to be updated periodically with the pole's current location. The model is vital for many navigational..."

everythingRF: Their Name Says It All

everything RF Searchable Database - RF CafePlease take a few moments to visit the everythingRF website to see how they can assist you with your project. everythingRF is a product discovery platform for RF and microwave products and services. They currently have 227,460 products from more than 1210 companies across 285 categories in their database and enable engineers to search for them using their customized parametric search tool. Amplifiers, test equipment, power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers, power supplies, and everything else. Please visit everythingRF today to see how they can help you...

Thursday 23

Bell Telephone Laboratories: An Adventure in Silicon

Bell Telephone Laboratories: An Adventure in Silicon, May 1955 Radio & Television News - RF CafeA few months ago, one of America's big-city mayors made the proclamation, "We're not going to make America great again. It was never that great." There has been a big push in the last decade to not only erase the significant accomplishments and sacrifices of America's and Western Europe's past, but to vilify those people and institutions that make up that past. Purging the records and rewriting history is a tried and true method of assuring few have easy access to archival material documenting the accomplishments of the nation's past. Along with desiring to provide useful and interesting material to people seeking technical and historical information, my motivation...

RFCafe.com Website Visitor Statistics for April 2019

RFCafe.com Website Visitor Statistics for April 2019 - RF CafeA supporting company representative requested that I update the website traffic statistics chart with current information since the old one was a year old. Wow, tempus fugit. April 2019 numbers are now available. RF Cafe typically receives 8,000-15,000 website visitors 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 8,000 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...

Radio-Electronics Subscription Letter

Radio-Electronics Subscription Letter, July 1969 Radio-Electronics - RF CafeThis subscription renewal for Radio-Electronics magazine was tucked inside one of the group of 1969 issues I bought on eBay. It's not a big deal, but is always interesting to see how the companies communicated with customers in the day. Note that the mailing address for Radio-Electronics is simply Boulder, Colorado, with no street address given - all the mailmen must have known where they were. The cost was $12 per year...

Some High Bandwidth O-Scope Facts

Some High Bandwidth O-Scope Facts - RF CafeSure, its really an infomercial, but the "Inside Story" piece in the May NASA Tech Briefs, written by Pico Technology's Mark Ashcroft, provides a good insight into what drives the cost of modern oscilloscopes. Per Mr. Ashcroft, "Back in 1928 Messers Nyquist, Shannon, Kotelnikov and Whittaker all concluded that to sample any continuous analogue waveform into discrete sampled (digital) form we must have at least two samples within a cycle of the highest frequency that we wish to represent. In practice we have to go further than that if want to reveal waveshape detail or make meaningful repeatable measurements..."

Electrical Machines - Transformer Action

Some Electrical Machines (Electricity - Basic Navy Training Courses, NAVPERS 10622, Chapter 21) - RF CafeThis line from the Basic Navy Training Courses is very important when considering electrical machines: Many electrical devices and machines operate on the principle of "transformer action." They in fact are not transformers - but the theory of their operation is best explained by considering them as if they were transformers. It is part of chapter 21, entitled, "Some Electrical Machines - Transformer Action," which provides a simple introduction to induction motors and generators, regulators, frequency converters, and synchros. If you are a newcomer to the field of electricity and/or electronics, or if you just want to brush up on old knowledge to be conversant at office parties, this is a great short read. A quiz is provided at the end...

USAF Deploys Missiles to Fry Weapons with Microwaves

USAF Deploys Missiles to Fry Weapons with Microwaves"The U.S. Air Force has deployed 20 missiles which can zap enemy electronics with powerful pulses rendering weapons virtually useless. They can be launched into enemy airspace at low altitude and emit blasts of high-power microwave energy that immediately disable any devices targeted. The Counter-Electronics High Power Microwave Advanced Missile Project (CHAMP) is the brainchild of Boeing's Phantom Works lab. They have not been operation until now and could be used to frazzle the military defences of Iran and North Korea, reports DailyMail.com. News of the state-of-the-art weapons - which are carried into battle by B-2 stealth bomber..."

QuinStar Technology: mm-Wave Active & Passive Components

QuinStar Technology designs and manufactures mm-wave products for communication, scientific, and test applications along with providing microelectronic assembly, rapid prototyping, and mass customization. Amplifiers, Oscillators, Switches, Attenuators, Circulators, Isolators, Filters, Waveguide, Antennas, Phase Shifters, Transceivers, Mixers, Detectors. QuinStar specializes in cryogenic amplifiers, circulators, and isolators. Please visit QuinStar today to see how they can help your project...

Wednesday 22

Mac's Service Shop: Simple Things First

Mac's Service Shop: Simple Things First, January 1960 Electronics World - RF CafeAfter many years of reading Mac's Service Shop sagas, a persistent theme seems to be Barney's refusing to refer to equipment schematics while troubleshooting, thereby often wasting valuable time. According to business owner and electronics sage Mac McGregor, assuming that what is typical for most sets will apply to all sets can and does create a fertile environment for frustration - and profit loss. Mac's advice to check "simple things first," has always been my troubleshooting philosophy - maybe because identifying the "hard things" has nearly been my undoing many times when the trouble is not simple. One of first things I do is check switches, connectors, and user-accessible potentiometers for proper operation (when potentially responsible for the problem, of course). I've written many times about how often a dirty connector is the culprit...

Filter Design with Discrete Elements Made Easy

Nuhertz Filter Design with Discrete Elements Made Easy - RF CafeIf you need to design just about any filter type ever conceived, then Nuhertz Technologies probably has software that can do it. The really big dollar microwave design software suites from Keysight and NI/AWR have synthesis tools, but if you only need to design filters, look no farther. Jeffrey Kahler has an article in MWJ entitled, "Complete Filter Design with Discrete Elements Made Easy," that gives some insight into Nuhertz's capabilities, but you'll want to visit their website to learn of the amazing depth and breadth of filter synthesis tools available. They also have many application notes that might be useful. A free trial and university versions are available...

Anatech Electronics May 2019 Newsletter

Anatech Electronics May 2019 Newsletter - RF CafeAnatech Electronics, an RF and microwave filter company, has introduced a new line of suspended stripline and waveguide type RF filters. Also, Sam Benzacar wrote as part of his May newsletter an article entitled "Wi-Fi Marches Forward, Unnoticed," which focuses on how advances in Wi-Fi are being made to address contemporary needs, while the news industry and subsequently users are largely unaware of the changes. 802.11ax, rebranded as Wi-Fi 6 by the Wi-Fi Alliance, provides data rate increases up to 37% over 802.11ac. Increased range and higher device connection counts, needed to cover large venues without extenders, is a big part of the performance enhancement...

Electronic Noise Quiz

Electronic Noise Quiz, August 1962 Popular Electronics - RF CafeOK, class, put your books away and take out a pencil. Spread your chairs out because we're going to have a short test today. A collective sigh permeates the room. Remember those days? I still have nightmares over those moments, and they were decades ago for me. At least this "Electronic Noise Quiz" from the August 1962 edition of Popular Electronics won't affect your GPA. Sometimes PE's quiz illustrations are kind of hard to interpret, but this one does a pretty good job (except item 'E', but I'm not telling what it is since nobody helped me). You will need a fairly diverse background in consumer type electronics to do well, and having a few gray hairs will probably help as well. Good luck. BTW, my score was a somewhat embarrassing 80%...

Elon Musk Shows off 60 Starlink Satellites Packed into Falcon Rocket - RF Cafe"SpaceX CEO Elon Musk tweeted out a picture of 60 of SpaceX's secret Starlink satellites packed into a Falcon rocket, ready to be launched this week in the first major test deployment of SpaceX's satellite-based internet intrastructure. Starlink Satellites Ready for Launch On Twitter this week, Elon Musk showed off 60 of SpaceX's new Starlink satellites being packed onto a Falcon rocket in advance of this week's mission to test the deployment of the satellites into low Earth orbit. In a series of tweets, Elon Musk showed off the satellites along with a similar picture of SpaceX's Starman just prior to its launch into space last year..."

KR Electronics: RF & Microwave Filters

KR ElectronicsKR Electronics designs and manufactures high quality filters for both the commercial and military markets. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop and individually synthesized filters for special applications - both commercial and military. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. All common connector types and package form factors are available. Please visit their website today to see how they might be of assistance...

Tuesday 21

Recent Developments in Electronics

Recent Developments in Electronics, January 1960 Electronics World - RF CafeThis "Recent Developments in Electronics" from a 1960 issue of Electronics World had a lot of antenna news that included a retarded surface wave antenna with high gain and low silhouette for use in airborne early warning radar as well as ground based and shipboard radar, a pair of 60-foot tropospheric scatter antennas that are specially mounted at opposite ends of a 180-mile long section of the Gulf of Mexico, and a 104-foot-long rotating 50-ton radar antenna used for the SAGE early warning system. Also reported was Westinghouse Electric's airborne Stratovision for broadcasting educational television programming to rural areas out of reach of existing towers...

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

Empower RF SystemsEmpower RF Systems is a global leader in power amplifier solutions. Empower RF Systems is an established and technologically superior supplier of high power solid state RF & microwave amplifiers. Our offerings include modules, intelligent rack-mount amplifiers, and multi-function RF Power Amplifier solutions to 6 GHz in broadband and band specific designs. Output power combinations range from tens of watts to multi-kilowatts. Unprecedented size, weight and power reduction of our amplifiers is superior to anything in the market at similar frequencies and power levels...

Extraordinarily Transparent Compact Metallic Metamaterials

Extraordinarily Transparent Compact Metallic Metamaterials - RF CafeAny Star Trek fan would immediately recognize this as Mr. Scott's "transparent aluminum." "In materials science, achromatic optical components can be designed with high transparency and low dispersion. Materials scientists have shown that although metals are highly opaque, densely packed arrays of metallic nanoparticles with more than 75% metal by volume can become more transparent to infrared radiation than dielectrics such as germanium. Such arrays can form effective dielectrics that are virtually dispersion-free across ultra-broadband ranges of wavelengths to engineer a variety of next-generation metamaterial-based optical devices ..."

Pop'tronics Comic Strip

Pop-tronics Comic Strip, November 1957 Popular Electronics - RF CafeThe 1950s was a time when futurists were predicting that domestic robots would be common place items in households. By the turn of the century, mankind, freed from the drudgery of manual labor, would have plenty of time for recreating, resting, and sitting around brainstorming the next big thing. Here it is 12 years into the new century and at the most, a fraction of a percent of the population even has a Vroom robotic floor vacuum - and it looks nothing like a human. This comic from the November 1957 Popular Electronics exemplifies the visions of the last century. Now, maybe by the end of the 21st century we'll finally be there...

Rohde & Schwarz: This Changes Everything!

Rohde & Schwarz: This Changes Everything! - RF CafeRohde & Schwarz introduces their "This Changes Everything" promotion which allows customers to purchase its oscilloscopes, spectrum analyzers, power supplies and power analyzers each fully equipped with the maximum bandwidth, channels, inputs, memory interfaces and signal generation for one affordable, unrivaled price. The promotion runs May 20 through December 31, 2019. Customers who might need to budget for future upgrades based on design needs can maximize their investment up front, making purchasing easier and less expensive. Save up to $10,000 on full-solution instruments...

Fighter Jets with Missile-Killing Lasers

Fighter Jets with Missile-Killing Lasers - RF Cafe"U.S. Air Force says a ground-based laser downed multiple test missiles over New Mexico. A successful ground test has moved the U.S. military one big step closer to putting anti-missile lasers on its aircraft. A ground-based laser shot down 'several' missiles in flight during an April 23 test at the White Sands Missile Range in New Mexico, Air Force officials said. Run by the Air Force Research Laboratory, or AFRL, the test was part of the Self-Protect High Energy Laser Demonstrator, or SHiELD, a program intended to protect aircraft from incoming missiles. AFRL officials said security reasons prevented them from saying how many missiles were downed in the test. The laser that the Air Force lab used for the test was ground-based...

Innovative Power Products: RF & Microwave Passive Components

Innovative Power ProductsInnovative Power Products (IPP) has over 30 years of experience designing & manufacturing RF & microwave passive components. Their high power, broadband couplers, combiners, resistors, baluns, terminations and attenuators are fabricated using the latest materials and design tools available, resulting in unrivaled product performance. Applications in military, medical, industrial and commercial markets. Take a couple minutes to visit their website and see how IPP can help you today...

Monday 20

Sansui TA-300 Integrated Tuner Amplifier

Sansui TA-300 Integrated Tuner Amplifier - RF CafeSometime around 1980, while stationed at Robins AFB, Georgia, I finally succumbed to the peer pressure of other more sophisticated audiophiles in the barracks and bought a "real" stereo. Unlike my roommate who had a full compliment of rack-mounted gear, my meager enlisted military pay only allowed for a mid-grade instrument. The solution was a Sansui TA-300 Integrated Tuner Amplifier. It put out a whopping 30 watts per channel, but unlike my existing radio (a Readers Digest 800-XR), those 30 watts were nearly distortion free when driving good speakers. Having only the pathetic 5 W speakers that came with the 800-XR, I designed a set of speakers rated for 60 W, and built the enclosures myself in the base woodshop. Unfortunately, in preparation for a household move about 20 years ago, I sold the Sansui and the speakers...

Today Is World Metrology Day!

Today Is World Metrology Day! - RF CafeIn case you forgot to put it on your calendar, today, May 20th, is World Metrology Day. To commemorate the occasion, this is the day that the official definition of the kilogram is being changed from a physical cylinder of metal to the equivalent mass (recall Einstein's E=mc2) derived from a photon energy-to-frequency ratio measured to its most precise value. Per the new definition, the magnitude of a kilogram would be "set by fixing the numerical value of the Planck constant to be equal to exactly 6.626 069… × 10–34 when it is expressed in the SI unit s–1 m2 kg (J s)..."

How Many Microhenrys in That Coil?

How Many Microhenrys in That Coil?, December 1931/January 1932 Short Wave Craft - RF CafeThis is a nice short article covering the calculation of inductances for coils wound on cores and wire sizes. It appeared in a 1932 issue of Short Wave Craft, but of course inductance has not changed since then so it is still relevant. The author recognized that standard formulas, although concise and accurate, are sometimes difficult to work with when calculations for a large number of values is needed for a particular circuit design. To address the situation, he presents a handy nomograph, chart, and a table of typical values. He also introduces a rarely seen term "Nagaoka's correction factor*" for skin effect. A smartphone app, a spreadsheet, or a desktop computer program would be used today to calculate inductance...

Positive Threshold in GaN Transistors with P-Type AlTiO

Positive Threshold in GaN Transistors with P-Type AlTiO - RF Cafe"The Indian Institute of Science claims the first enhancement-mode (e-mode) operation of aluminum gallium nitride / gallium nitride (AlGaN/GaN) high-electron-mobility transistors (HEMTs) using p-type aluminum titanium oxide (AlTiO) gate insulation. The metal-oxide-semiconductor (MOS) gate stack combined the high-k dielectric properties of TiO2 (k greater than 60) with the p-type properties supplied by Al2O3 doping (k ~9). The Al2O3 substitutes the 2Als on Ti sites and the 3Os have a deficit of one vacancy that is doubly positively charged. The charged O vacancy can release two holes, which can subsequently be reabsorbed by uncharged O vacancies..."

Approaching the 5G mmWave Filter Challenge

Approaching the 5G mmWave Filter Challenge - RF Cafe5G is providing plenty of challenges for filter designers. The issue is probably no so much achieving narrow bandwidths with extremely sharp rejection regions as implementation in available media. Peter Matthews, of Knowles Precision Devices, as an article entitled, "Approaching the 5G mmWave Filter Challenge," on the Microwaves & RF website that discusses some of the issues. "In the world of LTE, developers are very familiar with the available filtering technologies that work, namely surface acoustic wave (SAW) and bulk acoustic wave (BAW) filters. These filters cover a range of frequencies up to 6 GHz, come in small sizes and offer good performance-to-cost trade-offs..."

Bittele Electronics: PCB Fabrication & Assembly

Since 2003, Bittele Electronics has consistently provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly services. It specializes in board level turnkey PCB assembly for design engineers needing low volume or prototype multi-layer printed circuit boards. Free Passive Components: Bittele Electronics is taking one further step in its commitment of offering the best service to clients of its PCB assembly business. Bittele is now offering common passive components to its clients FREE of Charge...

Sunday 19

Engineering & Science Crossword Puzzle for May 19

Engineering & Science Crossword Puzzle May 19, 2019 - RF CafeThis week's crossword puzzle will keep you busy for a while. Since 2000, I have been creating custom engineering- and science-themed crossword puzzles for the brain-exercising benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. The jury is out on whether or not this type of mental challenge helps keep your gray matter from atrophying in old age, but it certainly helps maintain your vocabulary and cognitive skills at all ages. A database of thousands of words has been built up over the years and contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure...

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Amplifier Solutions Corporation (ASC) - RF Cafe

Innovative Power Products Passive RF Products - RF Cafe

KR Electronics (RF Filters) - RF Cafe