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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Please click here to view May 2014 homepage archive page 1.
Windfreak Tech designs, manufactures, tests and sells high value radio frequency products such as RF signal generators, synthesizers, power detectors, mixers, and up/down converters. We develop high quality, reliable, low cost products to make your life easier. Windfreak Tech is developing high quality, low cost products to make life easier for RF Engineers and hobbyist - all at low cost. Please stop by our booth (#1052) at IMS2014.
You or somebody you know needs this book. When author Barry Dorr told me a while back that he had a new book coming out aimed at recent college graduates and other job hunters, I figured it might be just another "Top 10" type collection of ideas which wouldn't hurt to know, but that would be too specific for general use. After reading through Ten Essential Skills for Electrical Engineers I can confidently tell you that is much more than one guy's opinion of what you should know to advance in your career. It is rare that I actually read through as much of an engineering book as I did this one. Mr. Dorr's primary goal is to provide...
Explore new ways to enhance power amplifier performance at the AWR sponsored webinar, Simulating Dynamic Load Modulated Amplifiers—an Alternative Solution to Maintaining Efficiency over a Power Range. This webinar introduces the concept of dynamic load modulation and demonstrates how amplifiers can be designed using this approach. The ability of the AWR tools to model nonlinear components using discrete components and parameterized variables gives the designer access to a fully dynamic simulation
Mr. Einstein believed everything is relative, and this 1963 article on the revolution of "microminiature electronics" certainly attests to the truth of it. Unlike with his Theory of Special Relativity though, travel near the speed of light is not needed to witness length contraction in the electronics realm; the passage of time and its attendant evolution of technology does that for us. Today's definition of 'microelectronics' will to our progeny seem laughingly absurd when they read about (or more likely have wirelessly implanted in their brain's memory cells) our current transistor gate widths of tens of atoms. BTW, Lilliput, in case you don't know, is the island nation of Gulliver's Travels where...
The Good Life is a free publication printed in northern Michigan. Along with advertisements and stories from local interests, every edition is chock full of humorous quips and jokes. These tech-related items are from the June 2014 edition.
Why Computers Should Be Considered Masculine:• In order to get their attention, you have to turn them on.
Fairview Microwave a preeminent supplier of on-demand microwave and RF products, announces their new lines of band pass and band reject tunable filters. Fairview Microwave's tunable RF filters are commonly used in lab environments for testing many frequency bands including PCS, UHF, PMR, Tetra, LTE, and WiFi. The tunable band pass filters and band reject filters, also known as band-stop filters or band-rejection filters, are effective in band selection or frequency discrimination with high attenuation greater than 50 dB
Decibels always have been and always will be a daunting subject to a lot of people. For electronics types, the issue of when to multiply the logarithm of the ratio by 10 or by 20 seems to be the biggest stumbling block. After many years of working with decibels, it becomes second nature. There are still instances, though, where I see seasoned engineers and technicians routinely confuse unreferenced decibel units (dB, the logarithm of a ratio) with logs of ratios referred to some base value (dBm, dBV, etc.). The bel unit was originally created to quantitatively assign changes in perceived levels of sound loudness...
The founders of Agile Microwave have over 100 man-years of experience designing, developing, manufacturing, marketing and providing innovative solutions to the industry. They have successfully designed and managed multi-million dollar technical projects from concept to completion. RF amplifiers using GaN and GaAs technology for class A, AB, C, D and E available up to 100 W CW / 150 W pulsed, WB & NB, up to 30 GHz. RF limiters switches, frequency multipliers, mixers, and integrated modules are among their offerings.
Sherlock Ohms is a regular feature by Design News where engineers and technicians describe their adventures of troubleshooting circuit and software problems. Quite often I can relate to the scenarios because of similar instances I've had over many years of being involved in electronics. This story by A. David Boccuti is very instructive in how to find the root cause of a problem in production that suddenly appears for no apparently good reason. In Mr. Boccuti's case it was a component refusing to be soldered properly when in the past there was never an issue. He did a commendable job in resolving the problem. Having begun my post-USAF electronics career as...
That John T. Frye was a great short story writer is a given truism based on his decades-long production of the Carl & Jerry series in Popular Electronics. It is easy to look over the fact that he also had artistic skills as well as evidenced by the pencil drawings that accompanied each installment. In this episode, our two electronics hobbyists build a resistor anemometer to measure wind speed from within their basement workshop. In the usually storyline style, one boy gives a lesson in circuit design while the other (also the reader) is the attentive student.
Advanced Test Equipment Rentals (ATEC) partners with Kaelus to become a rental distributor of Kaelus products. Kaelus manufactures Passive Intermodulation (PIM) Testers for the wireless telecommunications sector, and ATEC is one of the largest rental companies of test equipment for the telecommunications, aerospace, semiconductor, consumer electronic, and many other sectors. PIM, the non-linear junction that causes interference in the RF path
As mentioned in an earlier article, National Radio Institute (NRI) was one of the first companies to exploit the burgeoning field of electronics in the early part of the last century. They invested heavily in facilities and resources for producing educational material for both classroom and correspondence courses. Up until sometime in the early 1990s when throw-away electronics and almost total offshore manufacturing became the rule rather than the exception, there were always large advertisements in magazines offering to rescue floundering career seekers with promises of untold opportunities and riches from servicing radios, televisions...
It's going to be a hot time in Tampa next month in more ways than one. The RF and microwave industry may not exactly be producing the eye-watering revenue as other sectors of the economy but there are plenty of market and technology "hotspots" that will no doubt be evident at IMS exhibitors' product displays. For example, the wireless industry is evolving rapidly as LTE moves toward its next incarnation as LTE-Advanced, Wi-Fi morphs from discrete hotspots to a seamless network via HotSpot 2.0, and distributed antenna systems and small cells
Professors and executive staff at top colleges get paid lots of $$$ for their services. Add to that über generous retirement and benefits packages, the high cost of administering a plethora of social programs and politically correct courses, guest lecturers, and '<insert worthless topic> Studies' degrees, and expected donations to various popular causes. Throw in a prestigious brand name and maybe a sports team and the cost of actually getting an education can be really, really expensive. Many studies have shown that for the vast majority of people, the college that issues your diploma has almost no bearing on earnings after a few years of experience is gained...
For over 40 years KR Electronics has designed and manufactured high quality RF & microwave filters for the commercial and military markets. KR Electronics manufactures all filter types and individually synthesizes filters for special applications. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications.
This the the forth and final installment on a series written by Paul Rockwell discussing station design for long distance (DX) communications. Covered was antenna selection and siting (Part I), economics and construction(Part II), station configuration and receiver topics (Part III), and propagation quirks and this one - operating tips (Part IV).
RFdude.com LLC is a consulting company run by Lance Lascari. With the help of key clients over the years we have been able to take the business full time as of June 2008. Our goal is and has always been to be a highly technical resource for hire specializing in the design of RF, Wireless, and Microwave circuits and systems with occasional work in embedded control and signal processing. Projects over the years have been in the the aerospace, defense, industrial, telecom, and consumer electronics industries. We have solid resources in terms of equipment, software, and materials...
Corporate Welfare is alive and well in spite of political campaign promises to end it. According to a new Associated Press story, the median compensation for the CEO of a large publicly traded company crossed over into the 7-figure realm for the first time in 2013, with an average pay package of $10.5 million - an increase of 8.8% from $9.6 million in 2012. Why do I say corporate welfare? Simple, the increase is attributed primarily to a surging stock market, which is almost entirely funded by the Fed printing money (yeah, I know, it's not actually printed) and passing it into the coffers of bankers, investors, and businesses either directly via stimulus programs, quantitative easing, and bailouts, or via social programs, government contracts, hiring incentives for OTWM workers, and a multitude of other manipulations ...
Here is a brand new batch of RF / microwave engineering magazine articles for you.
» How Trends in Electronics
are Affecting Connectors,
(p22) B. Stanton
» Compact Antenna Snares
WiMAX/WLAN, G. Ghobadi
» GNSS Signals Are Used for
» Multiband Doherty Amplifiers
for Wireless Applications
((p30) A. Grebennikov
» GaN Solutions for Next
Communications, R. Baker
Engineering Fundamentals: An Introduction to Engineering, by Saeed Moaveni. Specifically designed as an introduction to the exciting world of engineering, the book encourages students to become engineers and prepares them with a solid foundation in the fundamental principles and physical laws. It begins with a discovery of what engineers do as well as an inside look into the various areas of specialization. An explanation on good study habits and what it takes to succeed is included as well as an introduction to design and problem solving, communication, and ethics. Once this foundation is established, the book moves on to the basic physical concepts and laws...
Being a great appreciator of good humor, and especially technology-related humor, I made sure to scan these comics from the pages of vintage Radio-Electronics magazines. You might have to have lived through the era of televisions with cathode ray tubes (CRTs) to fully appreciate the frustration of trying to acceptably grab, align, define, sharpen, tone, and lock an over-the-air broadcast signal on track. Stories of people putting feet or baseball bats through the sets were a big source of situational humor.
Excel-Wireless is a solution provider with many years of experience in the cellular amplification and wireless communications industry, serving private companies, universities, military and government agencies. We stand behind our products offering full service warranty, return and replacement, and installation support. We can produce up to 10,000 pieces of different cable assemblies every day. Not many factories can do that!
"...But, in a larger sense, we can not dedicate - we can not consecrate - we can not hallow - this ground. The brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember what we say here, but it can never forget what they did here. It is for us the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us - that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion - that we here highly resolve that these dead shall not have died in vain - that this nation, under God, shall have a new birth of freedom - and that government of the people, by the people, for the people, shall not perish from the earth." - Abraham Lincoln. November 19, 1863.
"Hey, I'm a good software engineer, but I'm not exactly known for my fashion sense. White socks and sandals don't translate to 'good design sense'." - Linus Torvalds, inventor of Linux
"Ground is ground the world around," is an oft repeated saying when talking about making electrical connections to Earth ground. In a general sense that is true, especially when referring to electromagnetic radio signals and antenna systems that are in some manner dependent on the common connection. However, when you are working within the confines of a localized electronic circuit such as on a printed circuit board or inside a chassis, there is no guarantee that without proper precautions ground is not at the same potential everywhere. Poor (high impedance) soldered, crimped, and bolted connections are among the prime offenders...
Anatech Electronics designs and manufactures the industry's widest range of RF and microwave filters at frequencies up to 40 GHz, as well as power dividers, directional couplers, and many other product types. We specialize in standard and custom designs for commercial wireless, public safety, satcom, and defense applications, and we can meet stringent military environmental specifications.
Sure, there are lots of resources on the Internet for identifying various screw types, styles, shapes, and sizes, but sometimes there are so many that it can be time consuming to peruse through them all, particularly if what you are looking for is an older type. This chart from a 1960 edition of Popular Electronics might be just the thing you have been looking for when working on a piece of vintage electronic and/or mechanical gear.
Here is this week's engineering crossword puzzle with words and clues focused specifically on the topics of communications, electronics, science, physics, chemistry, astronomy, mechanics, etc. There are no numbnut entries like names of movie stars or fashion designers - I leave those to the New York Times puzzle makers.
It is hard to believe that nearly two weeks have passed since I scoured the Internet for job hunting and career guidance articles. With graduation time being here, there is particularly a lot of information and advice for first-time job seekers. Of course if you are graduating and just now beginning your job search, you might be a little late to the party - so to speak. Have you considered a career serving your nation's armed forces? Some of the R&D and real-world applications experience...
This article purposes to set the record straight about the difference between John A. Fleming's 'thermionic valve diode' rectifier, which did not produce signal amplification, and de Forest's audion tube, which did provide amplification. U.S. patent number 841387, "Device for Amplifying Feeble Electrical Currents," was issued to Lee de Forest on January 15, 1907, a little over a year after Fleming received patent 803684 for his "Instrument for Converting Alternating Electric Currents into Continuous Current" on November 7, 1905. Unlike the contest between...
"Don't forget who brung you to the dance," is a variation of the old adage that admonishes you to remember who/what it was that provided the opportunity to be where you are now. It aptly applies to radio communications of all sorts. This short article from a 1932 edition of Radio News discusses the advent of radio beacon installations across America to facilitate air navigation during inclement weather. Before there was an FAA, the Department of Commerce handled commercial air traffic for passenger and cargo payloads. Aviation was on the verge of becoming a very profitable industry (the Douglas DC-3 would make that happen...
This crossword puzzle is a little trickier than some because it uses electronics abbreviations rather than full words. Not everyone uses the same abbreviation, so some answers are a bit more subjective. For instance, many people abbreviate the word 'transformer' as 'xfmr,' while others use 'trans' or 'trr' (I use xfmr). Where you really have to be careful, though, is with evolutional changes in terminology as is the case for frequency units, where 'cps' was most often used in 1958 rather than today's 'Hz." Enjoy.
X-Parameters: Characterization, Modeling, and Design of Nonlinear RF and Microwave Components, by David E. Root, Jan Verspecht, Jason Horn. This is the definitive guide to X-parameters, written by the original inventors and developers of this powerful new paradigm for nonlinear RF and microwave components and systems. Learn how to use X-parameters to overcome intricate problems in nonlinear RF and microwave engineering. The general theory behind X-parameters is carefully and intuitively introduced, and then simplified down...
Melanie and I are moving back to North Carolina and will be on the road for the next couple days. During the two-day drive, access to email will be limited until Thursday. Please forgive delays in responding. We have been away from NC for seven years and are returning at the behest of family members.
A while back I was taken to task for remarking on the seemingly crude (the word I used was 'barbaric") nature of some early medical machinery that appeared in a mid-20th-century edition of Popular Electronics (see "Electronics Against Cancer"). I won't repeat my mistake here when describing how early medical x-ray machines are scary looking. Admittedly, being stuffed inside a modern MRI machine and having the loud electromagnetic coils cycling is no relaxing trip to the countryside, but the x-ray machine shown here looks like the Q-36 space modulator beam Marvin the Martian might have pointed at the Earth to disintegrate it just before he asks, "Where's the kaboom?...
Pasternack releases a new family of low noise amplifiers (LNA) capable of high gain and broadband performance between 9 kHz and 18 GHz which are widely used across the spectrum of military and commercial applications. A total of fourteen new low noise amplifiers are offered. The new LNA category exhibits excellent broadband performance from 9 kHz to 18 GHz, noise figures between 0.8 dB to 3 dB, gain levels from 25 dB to 50 dB
The Good Life is a free publication printed in northern Michigan. Along with advertisements and stories from local interests, every edition is chock full of humorous quips and jokes. These tech-related items are from the May 2014 edition. • Kids, you'll never know the pain of digging the innards of a loved cassette out of a cheap stereo and crying as you wind it up with a pencil. • Twitter is proof that people should not be allowed...
In case you are new to RF Cafe or have just missed it, a couple years ago I released a free Excel spreadsheet titled RF Cafe Calculator Workbook that contains many worksheets with commonly needed calculations. It has Butterworth and Chebyshev filter plotters, mixer frequency conversion, radar horizon, directional coupler, VSWR, Pi and T attenuators, RF path loss and propagation time, and more for calculators. I have an Android App in the works that should be ready in a couple months, so stay tuned.
Vector Telecom has fully instrumented microwave, millimeterwave, & antenna laboratories and production facilities for up to 50 GHz. We provide microwave waveguide components and assemblies, coaxial components and antennas to global market. Vector Telecom consists of microwave and millimeterwave laboratories, antenna laboratories, microwave and electronic components factories.
"If they don't define themselves on the web, they're going to be defined by someone else." - Patrick Ambron, co-founder of BrandYourself, regarding personal and corporate reputation control on the Internet.
This Carl and Jerry episode is a bit far-fetched compared to the typical storyline, but it does illustrate how when you are desperate to get out a distress signal, a little technical knowledge and having a knack for improvisation can save the day.
Every Sunday I create a crossword puzzle using a word list that I personally created and added to during over a decade of making puzzles. All of the words are related to engineering, science, mathematics, chemistry, astronomy, etc. There are no numbnut clues about movie stars or clothing designers. Enjoy.
Other than taking college courses or attending seminars, reading technical books and magazine articles is one of the best ways to keep current on component introductions, circuit and system design methods, and industry news. I put a lot of effort every day into scouring the Internet for items that should prove useful to you in your endeavor as a professional and/or hobbyist. Here are a few of the latest.
» Thick Metal Cladding
Laminates, J-J DeLisle
» Measure Throughput of
Cellular and WiFi MIMO
Radios, F. Mlinarsky
» The Industry's Next Tipping
Point, D. Corman,
P. Moosbrugger, G. Rebeiz
» GaN-on-Diamond: The Next
GaN, Babic, Ejeckam, Lowe,
Mollart, Faili, Wilman, Dodson
Francis, Twitchen, Bolliger
» 10 Tricks That Extend
O-scope Usefulness, A. Pini
everythingRF is offering a free RF Calculator app for Android OS users. Among the many calculation functions available in this app are Pi and T, bridged T, reflection, and balanced attenuator calculators; unit converters for dBm to watts and watts to dBm; RF propagation and link budget calculators; coax and microstrip calculators; and noise figure, resonant frequency, skin depth, and VSWR calculators. Watch for more to added later
RIGOL is an emerging T&M leader and a technology innovator in electronic measurement. RIGOL's premium line of products including: DSOs, RF spectrum analyzers, DMMs, programmable power supplies, signal and waveform generators. DSA800 Series Spectrum Analyzer The DSA800 Spectrum Analyzer by RIGOL redefines the product category by setting new standards for performance and price. Its digital IF technology guarantees reliability and performance will meet the most demanding RF applications.