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 ...
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The battle between the serviceman and the customer is epic. The serviceman knows the customer is out to cheat him of his rightful due for expertise and availability, and the customer knows the serviceman will try to inflate the bill to finance his exorbitant lifestyle. This story from a 1945 edition of Radio Craft is a humorous take on the subject at first glance from the customer's perspective, but after reading it you might ascertain that it is really from the serviceman's perspective. An article from a 1957 edition of Radio News magazine titled "Strategy for C.O.D. Service" was written...
Free subscriptions are provided to qualifying applicants. Being qualified typically means working in a related industry and having product and/or services authority. After all, it is their advertisers that are paying.
FierceWirelessTech is the wireless business and technology report.
Microwave Engineering Europe is the leading journal for microwave and RF engineering professionals in Europe.
Wiley's Engineering for Dummies Book Bundle is a diverse collection of engineering tips, tricks, and insights from some of today's leading authors
Advanced PCB Techniques. As PCB designers get creative to continually amaze, the new techniques are disruptive to traditional PCB design and fabrication unless done well.
Anatech 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. Anatech has released new designs for a 1 GHz ceramic bandpass filter, a 310/370 MHz ceramic duplexer filter, and a 5.4 GHz ceramic bandpass filter. Ordered through their AMCrf web store.
"TV and the Internet are good because they keep stupid people from spending too much time out in public." - Douglas Coupland, Canadian fiction writer and cultural commentator, in JPOD (unfortunately, some still vote)
In 1991, Texas Instruments proudly introduced "The first electronic stacker for infants and toddlers." Clarance* the Stack-A-Round Clown features five layers of rotatable, flippable head/face rings that can be disassembled and reassembled by the player, with each removal and replacement of a ring initiating a spoken phrase by Clarance. How I came to own this mildly interesting toy is a story unto itself. I could not resist the urge to take the Stack-A-Round Clown apart to see what makes him tick (or talk, as the case happens to be). As shown in the photos, all the electronic heavy lifting is performed by a single speech synthesizer IC...
Here we go again with another set of enumerated steps for successful job hunting and career enhancement. It's almost comical how consistently the articles include an ordered list of tips. As with any area of your life, there is always room for improvement on your part and plenty of people ready to tell you how you can be improved. I often wonder how many of the people writing these advice pieces actually hate their jobs and wish they could devise the right advice for themselves to get a job they really like. Here are a few more useful articles:
Rohde & Schwarz is one of the world's leading manufacturers of test & measurement, communications and broadcasting equipment. With more than 8,700 employees and representatives in more than 70 countries, and world wide sales of almost $2.3B (€1.8B), we are able to support customers both globally and locally. Be sure to request the latest Spectrum Allocations Poster from R&S.
Although this article was published at the very end of WWII, it describes the efforts of the BBC during the war years to accommodate the loss of trained electrical and communications engineers to active military duty. The few qualified engineers remaining quickly went into action devising a training regimen of electrical theory and hands-on training. Men (boys?) as young as 16 years old, as well as women from 21 to 30 years old were selected after screening for aptitude. More than 2,500 people became technical assistants and some top performers earned certificates regarded in the industry as being on par with university degrees in engineering. The effort once again lends credence...
Admittedly, I'm not much of a team sports guy, but I was happy to see the land of my family's ancestors (Germany) win the World Cup. So, congratulations! As Sgt. Schultz would say, "Wunderbar!" As news was breaking about Germany defeating top South American contenders, Argentina and Brazil, I thought about how those two countries were the prime recipients of fleeing Nazi party members and collaborators after World War II who sought to avoid prosecution at the Nuremburg Trials. A lot of Europe's plundered wealth...
Were you making $7k/mo. in high school working as an intern? Evidently in the Silicon Valley area that is not uncommon. According to an article published by VB News, companies like Google, Facebook, Twitter, and Apple are paying their interns whopping sums of money for their expertise. Collected data shows that there is a wide gulf of space between top earners and bottom earners ($8,400/mo. vs. $1,000/mo. for Google), but the provided info does not specify whether that is for the same number of hours. It is probably a pretty safe guess that most of those at the top of the pay scale fully support the OWS protests against the world's "1%ers." Ignorance is bliss.
As soon as I read this headline I knew something seemed really familiar about it. Do you remember when the first euro coins were released back in the early 2000s? There were reports of people developing skin rashes that turned out to be caused by the nickel content in the coins. The United Kingdom's NIH found in 2004, "The results show that positive patch test reactions to euro coins can be obtained from nickel-sensitized individuals after 48 h of application to the palmar skin under occlusion. These results do not contradict other experiments in which repeated handling of coins was unable to provoke fingertip allergic contact dermatitis." You might reasonably expect that based on the notoriety...
NanoMEMS Research, LLC will presents an online course titled "Nanoelectromechanical Quantum Circuits and Systems (NEMX)." Dates of course are July 31 and August 1, 2014. This course introduces the emerging field of nanoelectromechanical quantum circuits and systems (NEMX). The field derives from exploiting progress in techniques for fabricating, down to nanometer-length scales, free-standing device structures that incorporate mechanical motion and that may be designed to perform a variety of functions, such as employed in electronics, RF/microwaves
Since 1992, Ophir RF has been designing and manufacturing RF/microwave amplifiers for military, T&M, EMC and scientific research applications. Products range 10 kHz to 40 GHz. Power levels 1 W to 25 kW. Ophir RF's specializes in replacing Radar Tube technology with solid state. Ophir RF is your RF power source for amplifier systems, amplifier modules, amplifier subsystems, and custom RF systems
With more than 200 clues and associated engineering and science themed words, this crossword puzzle will take a while. The big word for for a person who works crossword puzzles is 'cruciverbalist." According to Merriam-Webster, the word's origin is thus: "Latin cruci-, crux cross + verbum word + English -alist." According to sources, crosswords first appeared in England in the early 19th century, so there really is no formal Latin word for crossword. However, the literal translation of 'crossword' in Latin would probably be 'cruciverbum.' Class dismissed. Carpe diem.
This is a different type of electronics-related quiz from Quizmaster Robert P. Balin. Mr. Balin created many monthly quizzes for Popular Electronics magazine. Here you are provided a series of images and a list of men's first names, and you need to match the image to the name. There are nine in all. It is a good Friday afternoon challenge to help pass the time until the weekend begins. Enjoy.
Since 1994, leading wireless electronics companies have relied on 3Gmetalworx to deliver cutting edge solutions for advanced RF/EMI PCB-level shielding requirements. From prototyping and design services to JIT manufacturing supply, our clients depend on us to provide a seamless service pathway supporting entire product lifecycle. RoHS / WEE Compliant.
My personal midlife crisis is still awaiting funds to be properly executed. When and if it (the money) ever happens, the first thing I'll do is buy two cars: One will be a professionally restored 1969 Camaro SS like the one I owned as a teenager (see pic), and the other a brand new Camaro Z28 of whatever year the aforementioned financial windfall occurs. Melanie would prefer the Mustang or Charger. My '69 Camaro SS had the same 350 cu. in. small block V8 and heavy duty automatic transmission that came in the Corvette of the same year. It was styled after the Indy 500 pace car for 1969. What precipitated this story was a headline about Dodge announcing the very first 700+ HP...
Fairview Microwave, a preeminent supplier of on-demand microwave and RF products, announces their new line of single-channel/single-axis and single-channel/multi-axis RF rotary joints. Fairview Microwave's RF rotary joints are needed wherever RF signals have to be transmitted between stationary and moving parts of a system, commonly used in commercial and military radar, land-mobile-radio communications and anti-missile defense applications. These rotary joints boast a compact design, excellent VSWR, low insertion loss, and minimal variation
We are solidly into the hottest days of the year in the northern hemisphere. The normal high temperature here in NC is 89°F. It is the time of year that causes those less appreciative of hot, humid weather to conjure up memories of winter days with evergreen tree branches bending under the weight of the new-fallen snow. For those of you like me, here is a Carl & Jerry story that might help relieve the anxiety associated with knowing that in a few hours you will be walking out of an air conditioned building into 90-something-degree air and onto a blistering hot asphalt parking lot. AGW acolytes might find the story useful for submission to the official database of incontrovertible scientific evidence that the earth has been heating up since...
Of course you know that there are hundreds - maybe even thousands - of useful instructional videos available on YouTube and/or company and college websites. They can be a valuable resource for information on design, test, implementation, and theory on nearly any topic imaginable. The busier you are, the less time you have to watch one of the videos simply for review or general knowledge enhancement. However, some of the webinars, classroom lessons, company presentations, and privately done videos are very useful when you have a specific problem to solve. A lot of digitized productions from old armed forces and other government entities can be really useful even...
Having never owned a diesel-powered car or truck, I can't say whether not having a high tension (voltage) ignition system eliminates any possible interference with AM radio reception. Although not many people listen to AM radio these days, there was a time when it was still a popular option along with FM, and a time before that when it was the only option. Diesels have long been much more prevalent in Europe, so those of you who were around in the era might recall whether you were contently listening to the BBC in static-free bliss...
NuWaves Engineering is a premier supplier of RF systems, subsystems, RF products and engineering design services designed to customer requirements. We are a turnkey provider for RF and microwave communication custom designs with full project management and design responsibilities; taking ownership from the conceptual idea to production.
We are nine days away from the 54th anniversary of the first successful earth-moon-earth (EME) communication path by amateur radio operators. What is today a routine operation by Hams was a big deal back in the day. The moon was still a mystery to most of the world since at the time not even an unmanned probe had been sent for exploration. 1,296 MHz was the frequency of choice using a 1 kW klystron on the transmit end and a highly sensitive parametric amplifier on the receive end, with high gain parabolic antennas on both ends. The FCC has allocated...
Back-to-school ads are appearing already and many of you have or know kids heading off to college. Engineering Your Future: A Comprehensive Introduction to Engineering, by William Oakes, Les Leone, Craig Gunn, is an authoritative guide to the academic expectations and professional opportunities that help direct students down the path to a rewarding career in the engineering field. Features • Introduces students to the broad spectrum of engineering disciplines, with up-to-date data on degrees granted, employment opportunities, and salaries • Highlights the ethical responsibilities of engineers • Focuses on developing all-important problem-solving and...
Cobham Antenna Systems is pleased to announce the launch of its new Satcom Product Catalogue containing details of high-performance satellite feed chain, reflector and flat plate antenna products. The catalogue reflects 40 years of expertise in the design, development and testing of leading-edge satellite communications systems. A wide range of state-of-the-art horn-based and splash plate feed systems are available for prime focus and single and dual-offset antennas covering all the key satellite
The story accompanying this photo reports on China's use of unmanned aerial drones to monitor factories for illegal levels of pollution. Private automobile ownership and other forms of creature comfort are soaring in China, so the unbreathable air seen here is due not only to manufacturing the cheap products you buy at K-Mart. It is a joke that China, being exempt from Kyoto Protocol restrictions (it is a 'developing country'), has called on the U.S. to reduce carbon emissions. Why do our politicians (prez inc'l) continue to put us at a severe competitive disadvantage so as to cripple our economy? Are you tired yet of always being told how bad the U.S. is?
Pasternack Enterprises, an industry leading manufacturer and supplier of RF, microwave and millimeter wave products, announces their expanded line of 75 Ohm F attenuators. This new line of F-type attenuators is perfect for broadcast, HDTV and satcom applications in the L and S microwave bands up to 3 GHz. Pasternack’s new F attenuators are available in 1 to 10 dB values in 1 dB steps, with 16 and 20 dB values also available. These
Orbel Corp. is the leading designer and manufacturer of RF Shielding and EMI/RFI isolation products for printed circuit boards and electronic enclosures. Orbel also specializes in thin gauge photo etched metal parts and precision metal stampings made from a wide variety of material options. We manage every aspect of metal stamping from design, prototyping, short to medium runs and high volume stamping.
Nearly 80 years ago to the month, Admiral Byrd was ensconced in his Little America quarters under the Antarctic snow cover. Byrd Antarctic Expedition II had as its mission the documentation of weather patterns and meteor activity (which influences long range communications) in the vast, frigid nothingness. Radio communications were essential to survival both bodily and mentally. Little known to the outside world, or even to his encamped companions, Admiral Byrd had nearly succumbed to noxious fumes from the electrical generator he used to power his radio. Alone at an outpost and desperately ill...
The good RF & microwave articles just keep coming at an incredible rate. Here are a few of the newest from MPD, EDN, and MW&RF for your technical edification.
Evolve with Technology,
- PIM: Components, Material,
Handling & Testing,
(a Damm good article)
- RF Signal Capture and
Analysis System Serves
Commercial and Defense
- DigRF Devices Need RF
and Protocol Tests,
- Filter Assemblies Boost
Performance, J-J. DeLisle
Two items caught my eye in this group of news tidbits from a 1945 edition of Radio-Craft. The first was the drawing of a scheme for mobile-to-mobile as well as fixed-station-to-mobile radiophone service - cellular telephones! A frequency band of 152-162 MHz had been allocated for "urban mobile service." Towers and base transceiver stations would be erected along the most commonly traveled routes to ensure contiguous coverage. Two years later, in 1947, Bell Systems initiated its Mobile Telephone Service based largely on the principle presented here. The second thing that interested me was a plan by Raytheon to institute a microwave relay...
NuWaves Engineering, an international RF and microwave solutions provider, announced today that the company has been awarded a Phase I SBIR contract from the USAF Research Laboratory to research and develop advanced RF cavity filters for use on GPS III satellites. NuWaves worked with Exelis Geospatial Systems' Positioning, Navigation and Timing business to propose an innovative method to dramatically reduce the size and weight of space-based diplexers, triplexers, and quadruplexers – or "n-plexers" – for multicarrier
"In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual." - Galileo Galilei, Italian scientist and philosopher. Hmmmm... Does that apply to any major contemporary topic you can think of?
While working as an electronics technician at a defense electronics company back in my pre-engineer days (I was going to school at night), part of my job was to assist the assembly workers with issues concerning written instructions, problems with drawings, malfunctioning equipment, test conundrums, etc., for everything from cable harnesses to printed circuits and entire assemblies. Although it could be boring at times, the job did provide some challenges. A couple of the other techs in the area were former military guys like me, and they were pretty sharp. The Navy tar had serviced equipment at sea and was very adept at solving problems. One day, however...
Thanks to the incredible generosity of Artech House, there are now 6 new books available for choosing by the winner of RF Cafe's monthly drawing. I use many of the books as a basis for creating my 10-question quizzes.
Radio Frequency System
Architecture and Design
• Printed MIMO Antenna
• Precision FMCW Short-
Range Radar for Industrial
• Understanding Quartz
Crystals and Oscillators
• Practical Microwave Circuits
• Microwave Circulator Design
Electro-Photonics LLC is a global supplier of RF & microwave components. Our products include SMT hybrid couplers, wire bondable passive components, coaxial products, RF test fixtures and very useful test boards for evaluating components. The Electro-Photonics team can support your small R&D design requirements with RF & Microwave test fixtures and save you valuable design and characterization time.
Congratulations to Bob N., of Montgomery, IL, for being the June 2014 book winner. Bob wisely selected Ten Essential Skills for Electrical Engineers, by Barry Dorr (Graciously provided by Wiley-IEEE Press). I select at least one winner each month based on orders and, in Bob's case, pointing out errors on the website.
KR Electronics part number 3158 is a 10 MHz bandpass filter. The filter has a typical 1 dB bandwidth of 6 MHz and less than 1 dB of insertion loss. An Elliptic type filter is used for high selectivity and attains over 100 dB by 20 MHz making it suitable for harmonic cleanup. The filter is supplied with SMA connectors. Other frequencies and bandwidths are available.
In her article "The Five Deadliest Job Interview Mistakes," Liz Ryan contrasts an interview with a citizenship test vis-à-vis answer the question correctly = get your papers, but it doesn't happen that way with an interview. Continuing that analogy, my advice for America today is as follows: Just walk into a company and declare yourself an employee, occupy a cubicle, receive free coffee, a company T-shirt, and full benefits.
Here are a few more useful articles:
α Venture Capital: Europe
β Why Employers Don't Like
γ We Would All Rather Be
Working for Ourselves
δ The Right Keywords Are
Essential When Applying for
This week's engineering-theme crossword puzzle, like all others published on RF Cafe, uses only words pertaining to science, chemistry, engineering, astronomy, mechanics, software, computers, aeronautics, physics, etc. Names of capitals of countries nobody has ever heard of, mountain ranges, and movie stars will not be found here. Contact me if you would like a custom puzzle made for your school or organization (no charge).
Big Brother isn't the only one monitoring your every move. According to an extensive article in the July 2014 edition of Popular Science, the automobile repossession profession's system to unabashedly scan for and identify car and truck owners that are payment challenged might make an NSA agent envious - and at least for now it is completely legal. Using tow truck-mounted digital cameras, sophisticated license plate number recognition software, and a wireless link to a massive database, the current crop of repo men roam the highways and byways recording, time stamping, and GPS location fixing every plate it can find. Some trucks are outfitted with two, three, or more cameras...
This past Monday marks the first anniversary of the massive forest fire in the White Mountains of Arizona that claimed the lives of 19 "Hotshot" firefighters, so I thought maybe this story from a 1932 edition of Radio News would be an appropriate recognition of their sacrifice. Firefighters of all specialties have relied on radio communications nearly since its inception, and particularly once battery-powered versions became available for portability. It is hard to imagine a time when such a convenience - even a necessity - was not part of the standard firefighting outfit...
I have never seen study-at-home audio-visual (AV) physics courses offered by Albert Einstein or AV courses on chemistry promoted by Ernest Rutherford, but I can now say I have seen study-at-home AV courses offered by electronics pioneer Lee de Forest. This full-page advertisement for the de Forest's Training, Inc., company of Chicago, Illinois, appeared in a 1945 edition of Radio Craft magazine. The vaunted (at least by the company) "Syncro-Graphic" training was an early attempt at the paperless classroom...
Advanced Test Equipment Rentals, one of the largest rental companies of test equipment for the telecommunications, aerospace, semiconductor, consumer electronic, and many other sectors, to be featured on American Airlines "Executive TV" in-flight video entertainment program broadcasts during the month of July. "Executive TV" airs exclusively on American Airlines domestic and international flights worldwide and features many top companies
Electronics Weekly has published a three-part article detailing the results of what they call the "largest ever national survey of salary levels in the UK electronics industry." Represented sectors include design & development, sales & marketing, senior engineering & management, technical management, R&D, and T&M. With more than 1,000 respondents as a sample, it indicates that the average pay is up 2.5% over the last year. This reflects what is generally considered an improved manufacturing situation in the country. Over a third (37%) of the participants represent the D&D engineering sector, and that group reported earnings at less than the industry average of £46,321 ($79,447US). As usual, sales and management...
Start with a cage containing five monkeys. Inside the cage, hang a banana on a string and place a set of stairs under it. Before long, a monkey will go to the stairs and start to climb towards the banana. As soon as he touches the stairs, spray all of the other monkeys with cold water. After a while, another monkey makes an attempt with the same result all the other monkeys are sprayed with cold water. Pretty soon, when another monkey tries to climb the stairs, the other monkeys will try to prevent it...
The old adage about a picture being worth a thousand words is still true today, even in the Information Age in which we live. A lot of people, especially those new to the field of electronics, struggle with the concept of decibels as applied to power and voltage (and to a lesser degree current). A plethora of computer, browser, and phone app programs are available to make individual, specific conversions, but what has been learned about the fundamental relationship? A nomograph is still one of the best tools both for teaching and performing conversions. This article that discusses properly matching impedances of amplification stages...
Behavioral Modeling and Linearization of RF Power Amplifiers, by John Wood. Wireless voice and data communications have made great improvements, with connectivity now virtually ubiquitous. Users are demanding essentially perfect transmission and reception of voice and data. The infrastructure that supports this wide connectivity and nearly error-free delivery of information is complex, costly, and continually being improved. This resource describes the mathematical methods and practical implementations of linearization techniques for RF power amplifiers...
Werbel Microwave announces the release of its new model 40C22 dual-directional coupler that spans 80-1,000 MHz at 40 dB nominal coupling. The mainline is rated at 1.2:1 VSWR, 200 watts CW and a target PIM of -153 dBc. directivity is 20 dB in both directions. The unit ships standard with N-type female connectors, but may be customized to other types. Housing dimensions are 3 x 2 x 1.25 inches. The unit is coated with temperature-resistant ceramic based paint. The device covers a wide range of bands from FM radio to cellular. Made in the USA.
everything RF is a search engine for RF & microwave components. everything RF lists complete catalogs from various RF & microwave component manufacturers and enables engineers to search through them by specification. There are over 130,197 components listed from more than 377 manufacturers. Download datasheets, request quotes or contact the suppliers for more information via everything RF. Its Fast & Easy!
This quiz is based on the information presented in Practical Microwave Circuits, by Stephen A. Maas. "This book is a collection of things I learned. largely on my own, over forty years in microwave circuit design. While almost all of the material in this book existed somewhere in some form, no single source was comprehensive and accessible. I learned most of it by experience, talking to people and digging through technical papers and books. In some cases, I just had to figure it out..."
If you only get your news via the mainstream media, you might think all the jobs being "created or saved" have turned the unemployment situation around. The lap dog media out of ignorance and blind obeisance to a political party refuses to present news objectively. Are you recently laid off, have a relative that cannot find a job, or know a neighbor who has given up on meaningful employment? This line from Jean Shepherd's Duel in the Snow, or How Red Ryder Nails the Cleveland Street Kid comes to mind: "...the natives had been idle so long that they no longer even considered themselves out of work. Work had ceased to exist, so how could you be out of it?"
Here is an interesting relevant article written by Ben Casselman on LinkedIn: The Long-Term Unemployment Crisis Is as Bad as Ever
Skyworks Solutions unveils an integrated, single-stage, low-cost PIN diode limiter module to address the growing need for full receiver LNA protection in microwave applications. The SKY16601-555LF limiter is a low threshold / IL / distortion module in a surface-mount package meant for use as a passive receiver protector in wireless or other RF systems for frequencies up to 6 GHz. The module is comprised of a PIN limiter diode, an RF choke inductor, and two DC blocking caps at the RF ports in a two-lead MLP package.
"All in all, there seems to be no limit in sight to future electronic expansion." - Hugo Gernsback, electronics inventor, marketer, futurist, author, and publisher (quoted from "Our Growing Industry," 1958)