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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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.
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Please click here to view June 2014 homepage archive page 1.
We are solidly in the middle of baseball season in America, so this "Carl & Jerry" story from a 1950 edition of Popular Electronics comes at a good time. As is the case with many "Carl & Jerry" episodes, this one involves the use of an amateur radio rig. Find out how and why Jerry willingly commits "Baseball Interference" (BBI) to beat the opposing team at their own game.
Dr Sundaram Kumar, of American Standard Circuits, Inc., has published a paper titled, "Thermal Management of High Frequency Circuits by Blind Hole Technology." For effective thermal management of high power and dense electronics, the heat sink forms the bulkiest component, and aluminum, owing to its light weight and easy machinability, is the preferred choice for airborne PCB devices used in aerospace and defense telecommunications. In this paper, we present a versatile and robust fabrication...
Bittele Electronics is a leading Turn-Key PCB assembly manufacturer in the EMS industry. They will answer all your questions and solve all your problems in PCB design and layout, PCB fabrication, functional testing to RoHS rules, quick-turn PCB assembly, and FREE prototype PCB assembly.
Joe Cahak, owner of Sunshine Design Engineering Services, has submitted another fine article for posting here titled, "RF Connectors and Cables." It is a very nice treatment on various flavors of coaxial cables and connectors that includes specifications on the most commonly used types, governing equations, and recommendations on proper care and cleaning. Joe has also provided a list of the manufacturers, industry standards, and technical references he has found most useful during his many decades of automated RF testing experience. "RF Connectors and Cables" serves as a great introduction for newcomers to the RF and microwave realm, as well as a quick reference for bookmarking regardless...
Breaking news from May 1958: "Hardly a month passes nowadays without the announcement of some 'sensational' new amplifying device. The great majority of these startling inventions, after their brief flurry in the popular and technical press, disappear into oblivion. But we believe that the Tecnetron, just announced in France, has a brilliant and enduring future." Have you ever heard of a Tecnetron? I didn't think so; neither had I before reading this article in Radio-Electronics. I guess that pretty much negates the preceding prediction. The holy grail of the Tecnetron, whose etymology in and of itself is worth reading...
Here's what can (probably will) happen if you do like I did and fail to check the oil level in your air compressor. Fortunately, it was a cheap model so the oversight was was more of an embarrassment than a great financial loss. It would cost $98 to replace the entire compressor compared to $45 + shipping to buy just the connecting rod, piston, and counterbalance set (can't buy just the con rod). Metal from the con rod was seized on the shaft. 25¢ worth of oil and a little bit of good common sense would have prevented the loss.
For the sake of avid cruciverbalists, each week I create a new engineering crossword puzzle that has a theme related to engineering, mathematics, chemistry, physics, and other technical words. You will never be asked the name of a movie star unless he/she was involved in a technical endeavor (e.g., Hedy Lamar).
World War II came to an end in Europe in May of 1945, and in the South Pacific in September of the year. By the end of 1944, Americans were becoming confident that their fathers, sons, and husbands would soon finally be home. Manufacturers began advertising the eminent return and availability of consumer products that had gone out of production due to material shortages during the war years. Advertisements ran in trade and hobby magazines as early as 1944 promising lines of goods that in many cases had not even been designed yet or production planned. Some products being promised, however, were merely models that were already in production before...
At Spartant, our mission is to provide you RF test tools and instrumentation that are clean, uncomplicated and easy to use; nonetheless, our products are high-performance, rugged and exceedingly versatile. Whether you work in a development lab, production test, classroom or field, these tools will help you win the daily battles. Perfect for getting the job done efficiently and cleanly, yet not encumbered by features you don't need, Spartant delivers powerful, simple, electronic tools.
Z-Communications, Inc. announces a new RoHS compliant Fixed Frequency Synthesizer model 10625E-LF. The SFS10625E-LF is a single frequency PLL solution that is pre-programmed to operate at 10.625 GHz. This fixed frequency device utilizes ceramic resonator topology to achieve integrated RMS noise performance of better than 0.4° while consuming less than 500 mW of power. It is designed to operate over the temperature range of -30 to +70°C and delivers +3 dBm of output power into a 50 Ω load.
Having spent many years professionally scouring the Internet while attempting to identify electronic components as part of a reverse engineering effort, I can appreciate how difficult life would be when the only resources available were a few manufacturers' databooks and a magazine article or two. You might think it would behoove a company to make certain that its products are clearly marked if not with a part number, at least with an easily identifiable logo. That way a researcher could call the company, describe the part, and get the required information. Even with today's nano-size packages, laser marking could do the job. Sometimes, the maker of the next higher assembly (which might be the finished product) purposely either removes the identification from select components or instructs the vendor to only partially mark...
Is it my imagination or are these tech articles being published at a much faster rate than before? It sure seems like it to me.
- Receiver Sensitivity and Equivalent Noise Bandwidth (p.22), D. Layne
- Flexible and Low Cost Hands-On Lab for Antennas and Propagation, M. Pasian
- Reaching Beyond 100 GHz with Coaxial Connectors, W. Oldfield
- KKey Test Requirements of Modern Handset Power Amplifiers, D. Hall, H. Nelson, G. Pailloncy
- Microstrip Antenna Boosts UWB Gain,, R. Kumar, T. Oli, N. Kushwaha, R. Krishna
- Digital Predistortion Techniques for Mobile PA Test (p.32), H. Nelson, S. Ferguson
- Eight Errors Common To Spectrum Analysis, B. Nelson
NIC is a leading manufacturer of custom RF & microwave filters and assemblies. For over 20 years, we have been a trusted partner for military, commercial & space solutions that includes RF modules, phase shifters, multiplexers, filters, amplifiers, TCXOs, and more. NIC headquarters is located in Overland Park, KS with additional sales and manufacturing operations in Washington, DC and India.
Today's consumer electronics (CE) industry has an estimated value of $354 billion per a Statista report. In 1957, according to this article in Radio-Electronics, the market value was reported to be $13.7 billion ($116 billion in 2014 dollars per the BLS inflation calculator). The world population in 1957 was 2.89B and grew to 7.10B by 2013. That means population increased by a factor of 2.45 while the CE industry grew by a factor of 3.05. Within the margin of error of marketing expert estimates, that represents essentially flat growth. Fret not, though, because while the total spending on consumer electronics per capita might have been flat...
Anatech Electronics, Inc. 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 170 MHz cavity bandpass filter, an 882.5 MHz ceramic bandpass filter, and an 800 MHz helical bandpass filter. All can be ordered directly through their AMCrf web store.
This quiz from Popular Electronics is a bit trickier than others because it requires you to think abstractly rather than concretely. Quiz-maker Robert Balin presents a series of circuits and components along with the first letters of the related topics. Your mission, should you decide to accept, is to match the item to the letter. The example provided is matching the letter 'J' to a drawing of that type of half-wave antenna. I have to admit that my attempt at matching all of the items and letters was taking a lot of time, so I quit before finishing all of them; my hard head is better at concrete thinking...
Advanced Test Equipment Rentals, supplier of complete testing solutions for the Electromagnetic Compliance (EMC) market, is preparing for the last domestic IEEE International EMC Symposium, August 3-8 in Raleigh, NC, until it returns to Washington DC in 2017. Awareness of EMC is increasing with the growing demand of wireless communications for monitoring radiation and cross RF signals to ensure electronics are not affected. Also, the demand to plug equipment like solar panels back into the electrical grid is contributing to the growth of
Industry buzzwords are appearing these days faster than IRS scandals. 'NanoDegree,' coined by Udacity, is one of them. A NanoDegree provides, "Credentials built by industry leaders to advance your career." It is essentially another form of online certification in specific fields of study, in Udacity's case, Internet and IT. The ultimate mission is to reduce the requirement and expectation of a formal college degree - be it Associate, Bachelor, or even higher - for routine jobs. An intense introduction to or concentration on increasing specific skills, combined with on-the-job experience and instruction, is really all many high technology jobs require. In order to be a success, employers will need to be convinced of the value provided by abbreviated educational regimens...
Integrated Low-Power Radars, by Sergio Saponara, Maria Greco, and Egidio Ragonese. In recent years, advances in radio detection and ranging technology, sustained by new achievements in the fields of signal processing and electronic components, have permitted the adoption of radars in many civil and defense applications. This resource discusses how highly integrated radar has been adopted by several new markets such as contactless vital sign monitoring or harbor traffic control, as well...
Back in the early 1990s, while working for a fine Midwestern company that made automated utility meter reading (AMR) equipment, an older gentleman was hired as a contractor to do some design work. He was an instant hit with everyone not just because of his engineering prowess, but because of his stories of the mechanical and analog electronic computers he work on for the U.S. Navy. After being commissioned as an ensign at the U.S. Naval Academy in Annapolis, Maryland, he spent time studying, researching, and designing massive radar-directed gun pointing systems for battleships. Just as contraptions like Babbage's difference engine was a marvel of contemporary engineering...
Rohde & Schwarz recently played a major role in the FCC's crackdown on truckers using illegal GPS Jammers. On March 5, 2014, Rohde & Schwarz set up an instrumented van on a major highway connected to the Portland, OR, airport and determined that "about every third or fourth truck was radiating at or near the GPS L1 [frequency of 1575.42 MHz]." A report titled, "Strategies for Limiting Civil Interference Effects Inspired by Field Observations," by consultant Logan Scott, President, LS Consulting, included the R&S measurements in a detailed presentation on the issue of illegal GPS jamming and the hazards...
I love these kinds of stories because they involve a combination of luck and skill to solve a long-standing problem. The important lesson to learn from this story is that Michael Tompkins was smart enough to make the essential cause and effect link to be successful. To be honest, the scenario by which the discovery was made made me laugh out loud - not because of the pain caused to Mr. Tompkins but because I have experienced so many similar doinks myself.
Z-Comm has been leading the wireless world in VCO and PLL technology for over two decades. We are the largest manufacturer of VCO and PLL modules for the commercial / wireless market. To ensure our dominance as the leading RF / Microwave component supplier, Z-Communications, Inc. invests in continuous research and development to develop state of the art RF/Microwave components. We hold patents in ultra low noise technology, which enable us to provide excellent performance.
"Successful technocrats are not found among the ranks of such plodders of limited vision and ambition. Instead, they are found among those who aspire to eminence through their position in the technical hierarchy. Such men will find their climb made easier by the large number who choose to remain behind by practicing creative incompetence." - Archibald Putt, in his book Putt's Law and the Successful Technocrat. Hat tip to Lance Lascari, aka "RF Dude"
NI (formerly AWR Corporation) has published a new success story detailing how Ahsan U. Alam, a University of Alberta, Canada graduate student, successfully developed a modified top-of-the-barrier model for graphene field-effect transistors using NI AWR Design Environment™/ Microwave Office® circuit design software. Likewise, an IEEE paper detailing this venture was also recently presented and presented at the IEEE International Conference on Simulation of Semiconductor Processes and Devices.
This might be the first appearance of Carl's father, at least in a drawing. In this episode, Carl and Jerry design and build a "polecat detector." In the process, a little drama is thrown in when a stander-by mistaken believes he is being insulted. Even if you don't learn how a photocell-based threshold crossing circuit works, you might just learn the meaning of 'lugubriously.'
Somehow, a week has slipped by since last looking around for useful career and job hunting stories. For some reason these stories tend to have numbered lists. Here are 6 items from my latest roundup.
10 Things You Need to Know
About Working for a Startup
- 6 Signs Your Boss Is a
- Where Does Your Resume
Go? Inside the ATS System
(click on the infographic links)
- 4 Don'ts to Remember on
Your First Job
- How Much Time Should You
Spend on Your Job Search?
- Name-Dropping During an
"PCBs? We ain't got no PCBs in our TV sets... We don't have to give you no stinking PCBs." That is effectively what the Zenith television advertisement from a 1958 edition of Radio-Electronics told its potential customers. According to the Zenith communications department, even though their head R&D guy, Dr. Alexander Ellett, was "the daddy of printed circuit boards," they stuck with the traditional point-to-point wiring in all their TV chassis. I have to agree with them from a troubleshooting and component replacement perspective. There's nothing easier than heating a solder lug or terminal post to unwrap a leaded R, L, or C either to measure its value, isolate it...
If today's RF & microwave crossword puzzle was a galaxy, it would be classified as spiral. If it was top-down hurricane image, it would be in the southern hemisphere since it rotates clockwise; low pressure areas spin CCW in the northern hemisphere. In fact, the shape is not meant to represent anything in particular; it was just a convenient way to create the matrix.
Founded in 2005, LadyBug Technologies manufactures the PowerSensor™ line of miniaturized USB RF & microwave power sensors. LadyBug manufactures high accuracy average, pulse, and pulse profiling sensors with GUI interfaces covering up to 26.5 GHz and 80 dB dynamic range. These sensors set a, patented industry standard, no zero / no cal technology. There is no need to disconnect or wait for internal zeroing and calibration prior to making accurate low power measurements.
Rare is the time that I drag anything from my e-mail spam bin back into the inbox, but I do always check it just in case something slips by. The subject "Tesla Movie" is what caught my eye and caused me to investigate. Tesla proposes to be a full-feature, star-studded film documenting the life and times of Nikola Tesla. Its producers have turned to the increasingly popular 'crowdfunding' venue via Kickstarter as one aspect of fundraising to help bring it to fruition. Per the Kickstarter website pitch: "Why Crowdfunding? Quite simply we need a boost in finances to keep us going towards bringing this film to realization. We don't have the financial resources the big studios...
Except for a few notable examples such as the incredibly life-like humanoid robots coming from Japan, the overwhelming majority of robots today are either educational tools, special function equipment for performing highly precise tasks (surgical, exploratory, search & rescue), or part of high volume production lines. Back in 1940 when this 'Telecan' robot debuted, people though of robots almost exclusively as autonomous devices that would some day make life easier for the human race, or eventually conquer and subdue the human race into slavery. Constraining robots to the relatively inefficient layout and proportions of homo sapiens...
Advanced Test Equipment Corp. has in immediate need for an RF Calibration Technician to perform calibration and repair of medium to high level test and measurement equipment. The successful candidate will requires little assistance and supervision on to create calibration data sheets accurately and efficiently with minimal supervision based upon instrument specifications and approved calibration procedures, identify and recommend products and related peripherals and accessories to add to our rental inventory
Dave Harbaugh drew the semi-regular Hobnobbing with Harbaugh series of comic strips in Popular Electronics. His themes were always in the situational comedy style of the day where Ham operators were depicted as victims of their own obsession with amateur radio, their wives' lack of obsession with amateur radio, or being at the mercy of some well-meaning but ignorant neighbor, police officer, store clerk, or other such individual. This particular comic has an on-the-scene TV anchorman making KN3OB's life heck.
The 'Me' in this case is W4GKF (know to his parents as Chaz Cone), author of a very well-written and entertaining short story that is reminiscent of a Jean Shepherd radio tale. Hat tip to RF Cafe visitor Leon Robinson (K5JLR) for sending me the hyperlink. He was an accomplice to and co-conspirator with W4GKF in the confessed escapades.
Digital Filters for Everyone, by Rusty Allred. Performing such functions as noise mitigation and signal conditioning, digital filters are everywhere: in your car, in your TV, in your music player, in your phone, everywhere. But an engineering degree or expensive software is not required to design and analyze them. In fact, whoever you are and whatever your background, this book will help you understand, design, analyze and use digital filters. This book was written to make digital filters more accessible to everyone. Practicing engineers will appreciate its straightforward approach...
When I search for useful articles that offer career advice, I do a cursory scan through them to make sure there is no hidden bit of idiocy that ends up poisoning the entire thing. I would not want to recommend something without have at least performed some minimal amount of vetting. Sometimes, I don't need to go any father than the headline to flag it as idiocy. Take this one, for example: "How to Go from Working 60 Hours a Week to 40 by Sending 2 Emails a Week." The author has the very naive view that all a worker needs to do get away with working 40 hours each week is to send his/her boss an email on Monday morning outlining what he/she plans to accomplish in 40 hours by the end of the week, and then sending a follow-up on Friday afternoon...
Here is an interesting article that appeared in Popular Electronics discussing some of the early electronic system developments that were based on sensory elements found in nature. I'm a bit surprised and disappointed that the author made the mistake of equating a bat's sound-based detection and navigation system to radar rather than sonar. Yes, the principles of operation are the same regarding transmitting a signal and then computing the distance based on the round-trip time of the reflected signal, but there is a fundamental difference...
- Eight Errors
- Key Test Requirements of
Modern Handset Power
Amplifiers, G. Pailloncy,
H. Nelson, D. Hall
- Get Smarter About
Production Outlier Removal,
- Challenging the Status Quo,
D. Carlson, and
D. Pilgrim (I know Duncan)
- Flexible and Low Cost
Hands-On Lab for Antennas
and Propagation, M. Pasian
- Dr. Stephen Maas - 2014
Microwaves & RF Living
- Freescale's RF Test Bench
in a Box (video)
Here is a different type of quiz from Popular Electronics' master quiz-maker, Robert P. Balin. Rather than the typical format where you need to match a word or another picture with a picture, this one requires you to consider each description and decide whether it best describes an inductive, capacitive, or reactive circuit. I confess to messing up on question 20, because I couldn't remember whether a lagging power factor referred to voltage lagging current or current lagging voltage. Hint: It refers to current lagging voltage. Another hint: Remember the ELI the ICE...
KR Electronics part number 3157-1 is a 70 MHz bandpass filter. The filter has a min 0.5 dB bandwidth of 30 MHz. The filter is group delay and amplitude equalized. Stopband attenuation of 45 dB is maintained to 5 GHz. Elliptic type response for quick transition to the stopband. The filter is supplied in a 0.6" x 0.6" x 2.25" case with SMA connectors.
Don't be misled by the word "Maker's" in the title. "Maker" comes from Make magazine, the website that originally posted "The Maker's Bill of Rights" as created by Mister Jalopy, Phillip Torrone, and Simon Hill. The trio's collective lament and peeve is the manner in which so many manufacturers (aka 'the makers,' but not the object addressed in the title) produce products that are essentially unserviceable by users. It has been a topic of concern by many consumers ever since miniature and integrated components hit the product scene in the 1960s. "The Maker's Bill of Rights" was published around 2006. Permission has magnanimously been given to broadcast and promote it far and wide using the poster contained in this PDF document. As I read down the bullet list, I find myself agreeing...
Although I am not a proud miscomputerist (a made-up word) a la the sadly departed and much revered Bob Pease, I do allow myself the luxury of being emotionally affected at the sight of a hand-drawn circuit in a 21st century electronics magazine. Such is the case with Steve Bush's short article on the functional theory of a Cuk converter circuit. Its primary function is to invert the output voltage of a switching power supply using as few components as necessary. Rather than confuse (and bore) you with my interpretation, I'll let Steve do the 'splainin...
"On closer inspection, though, the first question to ask is whether computers are getting smarter or people are getting dumber." - David Auerbach, The Age columnist, in "Turing Test: What Eugene Said, and Why It Fooled the Judges"
If you want to know why high-end RF test equipment is so expensive, here is a clue: Look at all the gold-plated coaxial connectors on the back of this Agilent Technologies (aka Keysight Technology) FFT-based PXI signal analyzer. I show a screen capture of the front panel connections from a video narrated by Agilent's Joan Gibson at the IMS2014 show. In it, she demonstrates the difference between stepped vs. swept spectrum analysis. BTW, I'm only partly kidding about the connector-related cost drivers of instruments.
IC Interconnect is a leading supplier of flip chip wafer bumping, wafer level CSP and back-end services to the semiconductor and electronics communities. Our customers have world wide locations and are serviced from our manufacturing locations in Colorado Springs. IC Interconnect is seeking an experienced Sr. Engineering Manager to do development and manufacturing support in a high tech, high volume, small company environment on processes to support advanced packaging of wafer and die level bare silicon products
Fairview Microwave, a preeminent supplier of on-demand microwave and RF products, announces the release of a new portfolio of beak-over type torque wrenches used to precisely fasten RF coaxial connections between components and systems. Fairview Microwave has added a broad range of these break-over type torque wrenches suitable for multiple RF connector types including 1.0mm, 2.4mm, 2.92mm, 3.5mm, 7mm, SC, SMA, SMC, SSMA, SSMC, Type N and TNC designs. These RF torque wrenches...
Triad RF Systems was formed with the objective to solve the problem of high power RF amplifiers being the Achilles' heel in most RF radios. We have solutions for integrating high performance HPAs (10 MHz - 20 GHz) into sophisticated RF subsystems and systems without sacrificing efficiency and linearity. Triad RF Systems serves the military, satellite and commercial, medical, home land security, digital video broadcast, aviation and commercial wireless applications.
Linx Technologies, a long time supporter of RF Cafe, has a nice collection of RF app notes that do a nice job of boiling down to the basics of complex topics. They are well-written and have good visuals. Here are a few of their offerings that might be helpful.
- Guide to Wireless
Regulations in the U.S.
- RF 101 Information for the
- Modulation Techniques for
Low-Cost RF Data Links
- The FCC Road: Part 15 from
Concept to Approval
- Considerations for Sending
Data over a Wireless Link
- Understanding Antenna
Specifications and Operation
This week's science and engineering theme crossword puzzle won't take you long to complete. All you need for success is a knowledge of common technical terms and names. Being a trivia whiz on movies clothing designers, and exotic foods won't do you any good here.
As a premier manufacturer of RF Connectors, Cable Assemblies and RF Components, Dongjin Technology Innovation is highly recognized an RF industry leader in Korea. Our premium products offer a competitive price, on-time delivery and best quality in the industry. No Minimum Order. One Day Delivery MSDS Equivalent product suggestions with drawings and specification available. VSWR report on request. Whether your requirements are 1 piece or a million, Dong Jin TI has the knowledge and ability to produce your custom product.