Homepage Archive December 2013

Physics & Engineering

Crossword for 12/15/2013

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.

"Noise and Noise

Measurements" - Joe Cahak

Joe Cahak, owner of Sunshine Design Services, has submitted another paper on noise titled, "Noise and Noise Measurements." This is a very extensive treatise on noise definitions and their associated formulas as applicable to laboratory and report writing purposes. Derivations have been avoided in order to keep the focus on practical applications. Material is pulled from many established industry authorities on noise. I like the final sentence in the conclusion, "Clearly noise has much to teach us about many things and is of great use, in addition to being the bane of communications."

More Good Magazine Articles

This has been a good month for articles. Here are a few more you might find useful.

 - An Important Secret About

   Transmission Lines,

   by Eric Bogatin

 - Logging of RF Power

   Measurements (p.22),

   by Orwill Hawkins

 - Measurement Sensors: For

   a Calculator?,

   by Chris Grachanen

 - Leveraging the Use of a

   Radio Frequency Planning

   Design Tool for Modern

   System Design (p.30),

   by Malcolm Edwards

Empower RF Systems'

Airborne Pulse HPA Solution

Leveraging next generation hardware and software innovations that are part of Empower's “size matters” architecture, several unique configurations of these HPAs are being shipped to key customers. This particular set of high power HPAs build on the size, weight and power advantages already demonstrated with commercial product releases in the broad market, “size matters” product family. This recent and unique Airborne Pulse HPA solution features UHF and L-Band pulse amplifiers tied to a shared

Venture Technologies

Continues Support - Thanks!

"We are passionate about developing products that work better, and we have been delivering on that passion for 25+ years, helping dozens of companies bring innovative wireless products to market in a variety of markets. We design and develop products that analyze, measure, control, and communicate. Our in-house developed customizable, modular wireless platform, RFOS™ , allows us to do this better, faster and with less NRE cost. We wrap our core embedded wireless capability in full service 'spec to production' product development."

A New Look at W1AW/p>

The American Radio Relay League (ARRL) has been on the cutting edge of communications technology since its founding in 1914 by Hiram Percy Maxim. Then, as now, many of the nation's top electronics and antennas experts have been intimately involved in the design, testing, operating, and regulating aspects of radio systems. Over time radar, software, and computer technologies have been added to the mix of specialties as have program management, field deployment and fixed station logistics, facilities management, and many other talents. A natural result of all the human capability affiliated with the ARRL is the collective personal investment in keeping flagship...

7th Circuit Excoriates Lawyers,

Judges for 'Fear of Science'

IMS ExpertServices periodically sends me e-mails that highlight recent key court cases that can significantly affect the effectiveness of expert testimony, both for the plaintiff and for the defendant. This article by Bob Ambrogi reports on a 7th U.S. Circuit Court of Appeals judge spanking legal entities for not exercising due diligence when vetting matters of science and simply accepting the testimony of 'experts' because of a willful ignorance of science. "This lapse is worth noting because it is indicative of a widespread, and increasingly troublesome, discomfort among lawyers and judges confronted by a scientific or other technological issue," Circuit Judge Richard A. Posner wrote." We are used to hearing people - professionals included - dismiss their lack...

A Few Useful Articles

I do a fair amount of perusing tech articles on the Internet and found a few recently that might be of interest to you.

 - Lab Equipment: To Build

   Or Not to Build

 - Six Tips for Better TDR

   Measurements

 - Open-Source Financing

 - Wanted: Brightest and Best

   Young Engineers for

   DesignCon Panel

 - Active Antenna Systems

   Enjoy Growth

Skyworks Customized Optical

Solutions for Varian Medical

Skyworks Solutions, an innovator of high performance analog semiconductor enabling a broad range of end markets, today announced that its wholly-owned subsidiary Isolink is shipping customized optical solutions to Varian Medical for radiation oncology applications. Varian is the world's leading manufacturer of medical devices and software for treating cancer and other medical conditions with radiotherapy, radiosurgery, proton therapy and brachytherapy

Please Thank Kete Microwave

for Their Continued Support!

Kete Microwave Electronics Co., Ltd. specializes in designing and manufacturing state of the art RF/Microwave passive components solutions including isolator/circulator, RF resistors, terminations, attenuators, multilayer chip ceramic capacitors, feed-through capacitors, directional couplers, power divider/combiners, 3 dB hybrid couplers, etc. Connectorized, surface mount, drop-in, and waveguide versions available.

Crossword Puzzle

Nov 1960 Electronics World

Cruciverbalists rejoice! Here is another crossword puzzle to try your technical prowess. Unlike the weekly RF Cafe crossword puzzle that contains only engineering, science, mathematics and other tech words, this one from Electronics World does have a few unrelated words. The big difference between making crosswords then and now is Mrs. Le Fevre had to construct the grid of words manually, whereas I just create a huge file of words and definitions, draw the grid outline, and then click a button to have software put it all together. I'm guessing it took a couple hours to make this puzzle; mine take about 15 minutes.

RF Cafe is Back in Full Swing

- from Alpena, Michigan

RF Cafe is back in business full-time! After a busy, tiring few days, Melanie and I have completed our relocation from Erie, Pennsylvania, to Alpena, Michigan. Why did we leave Erie and why did we move to Alpena? The answer is multi-faceted. Although we really like Erie, the state of society has really degraded there since we moved there six years ago. Property and school taxes, while already very high to begin with, have increased significantly over that time. A news article from Erie this morning, read online, reported that school taxes will increase yet again...

Carl & Jerry:

Under the Mistletoe

I know what you're thinking... but remember, this was 1958. I've been waiting for months to post a couple Christmas-themed Carl & Jerry articles from old editions of Popular Electronics. Carl & Jerry, if you are not familiar with them, are a couple electronics-savvy teenagers who, in the style of the Hardy Boys, manage to get involved in a series of criminal investigations. With headquarters based in their parent's basement, the two friends cobble up strategies and contraptions for snaring the bad guys. They have quite an impressive collection of test equipment and radio gear at their disposal per the drawings. In this episode we are introduced to the word "osculation." If you already know, don't tell us.

Notable Tech Quote

"The facts and knowledge learned in any course will become obsolete well before you retire. The ability to think critically is a skill that will last a lifetime." - Kenneth C. Young, University of Arizona, in December 2013 Scientific American

Thank to Dow-Key Microwave

for Their Continued Support!

Dow-Key Microwave is the world's largest manufacturer of electro-mechanical RF switches. We are AS9100/ISO-9001 certified and committed to providing unparalleled customer service, competitive pricing, on-time delivery and products that are distinguished by quality and reliability. Dow-Key offers the largest switch product line in the world with over 10,000 unique configurations.

Notice: Household Move

in Progress

Please excuse any delay in response for the next couple days - maybe through Tuesday. Melanie and I are moving to our new (well, new to us) home in Michigan and will be on the road for a bit. Thank you for your patience.

Electrical Engineering

Crossword Puzzle

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.

Modeling Radiation Patterns

of Whip Antennas

Computer modeling of antenna radiation patterns has evolved from a relatively simple electric field equation that diminishes as the inverse of the distance from the source, to exotic, highly sophisticated numerical methods that account for conducting and dielectric surfaces and volumes. A spreadsheet can be built rather quickly to calculate and graph the free-space azimuth and elevation e-field patterns for a 1/4-wave whip or a dipole antenna using textbook formulas, but building a model for displaying the 3D radiation patterns of a cellphone placed next to a human head, or a UHF radio antenna on top of an aircraft takes some pretty serious computing power. In large part we owe a debt of gratitude to the Ph.D. types who have labored hard to make such tools...

Anatech Intros Duplexer, BPF,

Isolator, & Directional Coupler

Anatech Electronics has released new designs for a 902 to 928 MHz cavity bandpass filter, a 1850 to 1910 MHz/1930 to 1990 MHz cavity duplexer, a 840 to 960 MHz circulator , and a 5 to 18 GHz 8-way power divider. All can be ordered directly through their AMCrf web store.

Please Thank Nova Microwave

for Their Support

Nova Microwave is a leader in technically differentiated electronic and radio frequency Ferrite Circulators and Isolators that connect, protect and control critical systems for the global microwave electronics market place including commercial and military wireless telecommunications. Dedicated to R&D of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz to 23.6 GHz.

Coil Function Quiz

Here is a quick, 10-question quiz about coils (inductors). It appeared in the June 1962 edition of Popular Electronics magazine. Don't be scared off by the vacuum tubes that appear in three drawings. Just pretend they are transistors - it won't affect your answers. One of the coil applications is almost obsolete for most people as the nature of computer monitors and TV screens has changed significantly in the last decade.

Selected Job Tips from IEEE

Here are this week's suggestions, plus a couple others I found as well.

 - 6 Memorable Engineering

   Interview Questions

 - 7 Missed Opportunities

   That Can Cost You That

   Dream Job

 - Can You Make a Workplace

   U-Turn? (leave, then go back)

 - How's the Engineering Job

   Market? Depends on Whom

   You Ask

 - Engineering the Perfect

   Cover Letter

 - U. of Maryland School of

   Engineering job Search Tips

Thanks to Windfreak

Technologies for Support!

Windfreak Tech designs, manufactures, tests and sells high value radio frequency products such as RF Signal Generators & Synthesizers, RF Power Detectors, RF Mixers, RF Upconverters and RF downconverters. 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. Future products will be more synthesizers, transmitters, receivers and test equipment. All at low cost.

The Future of Mobile

Application Development

Forrester Research Report: The Future of Mobile Application Development. This report, which is the vision report of the mobile app development playbook for Application Development and Delivery professionals, focuses on the changes application developers need to understand if they want to build modern applications that deliver contextual customer experiences. With more than 1 billion smartphones worldwide, and tablets numbering in the hundreds of millions, the scope of the mobile revolution rivals that of the move from monolithic systems to client/server computing in the 1990s...

Baluns: What They Do

and How They Do It

Baluns are not devices familiar to most engineers even if they have been in the RF business for many years. Most have heard of them but few probably really know what a balun is, how it works, and how it is used. Admittedly, it wasn't until maybe a decade ago that I ever even came into contact with one - at least that I was aware of. Having spent most of my career connecting cables and waveguide to pre-designed, pre-packaged components, there was never a need to convert between balanced and unbalanced transmission lines. The many analog circuits that I did always used ICs that had single- or double-ended inputs and/or outputs so it was never necessary to be concerned with the details. Now that I have been reading the ARRL's QST magazine monthly for the last few years, an appreciation for...

What is a Servomechanism?

Servomechanisms are all around us in the form of electronically actuated controls for our cars, stepper motors in our ink jet printers, overhead garage door openers, and anywhere else you can identify where a combination of electricity and mechanics operates with some form of positional sensing and feedback. The author of this article in one instance declares a control circuit with a human operator as part of the operation as being "open loop," but I contend that the human element is part of the loop and therefore constitutes a component in the effectively "closed" loop, albeit not strictly a pure electromechanical system. Those of us who operate radio-controlled model airplanes, boats, cars, etc., are very familiar with servos for moving control surfaces as commanded by the transmitter's joystick position.

How to Break into

the Aviation Radio Game

Yes, this is another article that will probably appeal to a small percentage of RF Cafe visitors, but please countenance my indulgence in things aeronautical as well as things electrical. The early 1930s was a time when both airplanes and electronics were a wonder and a mystery to most of the public worldwide. Of course today both are still a mystery to the public but the wonder is gone - it's merely taken for granted. Many idiosyncrasies of airborne electronic communications were encountered for the first time, like the need for proper grounding and static electricity dissipation. Ruggedization of chassis assemblies in terms of mechanical vibration and shock as well as for temperature extremes...

Featured Books

- Gift Suggestions -

Your New Job Title Is "Accomplice," by Scott Adams. If you are looking for a gift for your engineer spouse, friend, son, or daughter, then what could be better than the latest collection of Dilbert comics? Both traditional paperback and newfangled Kindle versions are available. Not the reading type? How about a Dilbert 2014 Calendar? Seriously, if you are buying the calendar because your engineer is not a reader, then he/she would be better served with Learn to Read, by Zac the Rat (the name doesn't really rhyme, BTW).

Does Anyone Still Make

Vacuum Tubes?

Does anyone still manufacture new vacuum tubes? The simple answer is yes if you are referring to the kind used in household radio and television sets, but don't expect to find a full line of replacements. Also, don't expect them to be made anywhere other than places like China and Russia. China does it because mainly to service the rest of the world's demand for restoring and maintaining vintage equipment. Russia probably does it to supply its own military and civilian populace which largely still hasn't heard of transistorized electronics (just joking, kinda). Three of the most widely available newly produced vacuum tubes are made by JJ Electronics, Valve Art, and Ruby Tubes. They are all over Amazon.com and eBay at reasonable prices. If you are in the market for vacuum tubes and prefer to buy...

Please Thank Reactel

for Helping Deliver RF Cafe

Established in 1979, Reactel is an industry leader in the design and manufacture of RF and Microwave filters, diplexers, and sub-assemblies. We offer a line of filters covering DC-50 GHz. The latest in CAD/CAM methods and equipment in all of our design and manufacturing processes are used. We feature a modern, well-equipped machine shop complete with multiple CNCs, which gives us the ability to produce long production runs quickly and economically. Our testing department is equipped with the latest in Agilent Technologies Network Analyzers offering quick, dependable, and accurate measurements.

Sagetech Announces Principal

Development Engineer Position

This is one of the best job descriptions I have ever seen. It reads like it was written by real engineers who need a really good person to work with the team. To wit:

EE UAV Avionics Design and Certification

"Unmanned Aerial Vehicles (UAVs) in civil airspace are the next big thing. Sagetech is a leader in UAV avionics and has exciting projects starting now in FAA / military UAV design and certification. We are building a kick-ass team. You might fit if this grabs you:  We seek highly talented, disciplined, imaginative engineers (RF design, embedded, or FPGA programmers) who love creating novel and highly efficient solutions in a requirements-based design environment. That's not easy. We seek team members who are like us, who are energized by challenge."

Mary Burke, W3CUL Wins

1956 Edison Award

$5,000 in 1956 currency is equivalent to about $43,000 in 2013, per the U.S. Bureau of Labor Statistics' "Inflation Calculator." That is the value of the amateur radio equipment used by Mrs. Mary Burke in her work handling "an average of 3000 messages per month, principally for service personnel overseas." For her tireless efforts, she was the first woman to win the coveted Edison Award Cup (sponsored by General Electric). Most of Mrs. Burke's communications was via Morse code, where she restrained herself to "about 30 words a minute to maintain accuracy". Way to go, Mary!

Neverware Juicebox

New Life for Old Computers

Remember the old adage about not throwing away that wide tie because someday it will be back in style? Well, the good folks at Neverware have built a business model and product that exploits that concept. "Neverware installs powerful software on schools' existing computers, taking over the 'heavy lifting' and allowing the computers to run like new. Neverware's servers can supercharge any PC - even if it's ten years old and missing its hard drive." Those of us who have been using computers since the 1970s ['78 for me] know this system as a network with dumb terminals. The main difference between then and now is wireless connectivity rather than copper cables. Calling the server a "Juicebox" helps the sales pitch and with cinching the deal - it sounds trendy. I have long predicted that the "personal" computer in business and other large networks like in schools and government offices would eventually come full circle...

Notable Tech Quote

"Twitter is the only place where you're thrilled when a complete stranger starts following you." - Anon

PMI Intros PIN Diode Transfer

Switch for 0.5 to 18 GHz

PMI Model No. SWN-2181-TRA is a pin diode transfer switch that operates over a frequency range of 0.5 to 18.0 GHz. It has 60 dB min of isolation, max insertion loss of 3.5 dB and a max input power of +10 dBm CW.  This model incorporates a TTL compatible driver for easy system integration and is supplied with removable 2.92 mm (F) connectors in a housing that measures 1.0" x 1.0" x 0.25"

The Swiss Quad Antenna

This design for a "Swiss Quad" antenna appeared in the September 1967 edition of QST magazine. One of its touted strong points is not needing spreaders or a boom. I am not an antenna design guy, so I can't comment on its usefulness. No gain measurement was provided by the author. The article states that the antenna had not yet enjoyed widespread adaptation in the U.S. at the time of the writing. A Google search for Swiss Quad antennas turns up a handful of modern examples. I could not locate an example of a computer-generated gain plot (radiation pattern) for the Swiss Quad, so if you know where one exists, please let me know so I can post a hyperlink. Maybe you own a  copy of EZNEC and can model it?

Wireless Crossword

for December 1, 2013

This is a BIG crossword puzzle so be prepared to spend some time on it. In fact, if you find yourself being dragged along for a major Christmas shopping jaunt, then you might print it out and take it with you to be entertained whilst sitting on the mall bench. As always, this puzzle contains only science, engineer, and mathematics type words - no numbnut movie star names or obscure mountain peak names.

The Maser: Receiver for Signals from Space

When really good researchers set out to write books on history, they do not simply cull information from the publications of fellow contemporary authors; instead, they look for sources that were published during or around the time of the subject being covered. Doing so helps minimize the possibility that inaccuracies have crept into the knowledge pool and that information other authors might have either deemed insignificant or have missed can be recovered. With a bit of luck, sources are discovered that have never been used before. That is part of my motivation for going to the trouble of buying these vintage magazines and posting articles like this one which reports on early maser developments. It delves fairly deeply into the solid state physics of rare earth minerals that early masers and lasers relied upon to function, including energy band...

Featured Tech Book Tech Business Start-Up

Starting a Tech Business: A Practical Guide for Anyone Creating or Designing Applications or Software, by Alex Cowan. Why not make 2014 the year you finally launch the business you have been thinking about and/or working on seemingly forever? "Starting a Tech Business offers practical checklists and frameworks that business owners, entrepreneurs, and professionals can apply to any tech-based business idea, whether you're developing software and products or beginning a technology-enabled business. You'll learn: 1. How to apply today's leading management frameworks to a tech business 2. How to package your product idea in a way that's highly actionable for your technical team 3. How to ask..."

2013's Final Tech Articles

Yep, hard to believe but it's the last day of 2013. These are some of the final good tech articles of the year. 2014 holds lots of promise for our industry and there are already many good articles sitting queue for publication. You'll see them announced here. If I miss something, please let me know.

 - In Defense of DARPA;

   Lamenting Bell Labs,

   Barry Manz

 - Tapping into a New RF

   Energy Source Found in

   Digital Processing Circuits,

   Michael Hopkins

 - Detecting ESD Events

   Kenneth Wyatt

 - Active Antenna Systems

   Enjoy Growth, Iliza Sokol

 - RF Technology in Semi

   Wafer Processing,

   Abdullah Eroglu

Technical University of Denmark's Anechoic Chamber

Popular Science magazine ran a short feature titled "Outer Space, Indoors," in the January 2013 edition. The main photo is a shot of the inside of the RF anechoic chamber at the Technical University of Denmark (DTU). Its thousands of RF absorbing pyramids are painted a dark, electric blue with black tips, which makes for a very stunningly artistic image. Narcotics-inspired sculptors of sculptures could scarcely improve on the visual impact of this imminently and supremely functional structure. Interestingly, I could not find a single picture of the anechoic chamber on the DTU website other than a small section of it from before the new paint job. According to my search for the original, the one in PopSci appears to have originated on the website of photographer Alastair Philip Wiper, where many high resolution views of the anechoic chamber's inside are posted. A steel Faraday cage encloses the chamber, but I could not find any photos of it. A picture of the power, data, and RF cabling interface(s) would have been interesting to see.

Thanks to Pulsar Microwave

for Continued Support

Pulsar Microwave is a valued supplier of high quality RF and microwave passive components in the frequency range of DC to 85 GHz. Because of our large library of designs, we are able to provide custom products with little effort and in most cases with no additional price increase above the standard catalog item. New products are introduced on an almost monthly basis, the most recent of which are high power directional couplers and power dividers.

Notable Tech Quote

"Scientific knowledge is an enabling power to do either good or bad - but it does not carry instructions on how to use it." Theoretical physicist Richard Feynman in The Value of Science

Microwave Engineering

Crossword Puzzle

This is the final engineering crossword puzzle for 2013. The year sure has flown by, as they all do anymore. As always, all the words are engineering, science, mathematics, chemistry, astronomy, etc., related. 2014's first crossword is a monster, so be prepared for a challenge in January.

Skyworks Introduces WLAN

FEM for Smartphones & Tablets

Skyworks Solutions introduces a highly integrated 5 GHz WLAN front-end module for reference designs targeting smartphones and tablets in a 2.5 x 2.5 mm, QFN package. The SKY85702-11 incorporates a power amplifier and a SPDT transmit and receive switch for mobile/portable 802.11ac applications and systems. Operates from a single supply voltage of 3.6 V, with an enable/disable function that allows power savings during off mode. Integrated power detector with 20 dB of dynamic range provides closed-loop power control within the system.

Crossnumber Puzzle

Here is a rather unique type of crossword puzzle that uses numbers rather than words. It appeared in the April 1959 edition of Popular Electronics. The software that I use to create the RF Cafe crossword puzzles each week has the ability to create such a puzzle, but I have never made one because it would take a lot of time to build a clue / answer file to be drawn upon for input. Maybe some day I'll do it, though.

The Vacuum-Tube Voltmeter D.C. Ranges

Popular Electronics ran a 5-part series on test equipment usage. This installment is on the use of a vacuum tube voltmeter (VTVM) for making DC measurements. Don't pass over the article just because it refers to a vacuum tube tester since there are lessons that apply to even the most modern transistorized, computerized meter. Author Larry Klein discusses mainly the DC functions, providing both functional descriptions of the circuits and how to use them for making accurate measurements. FET-input digital multimeters (DMMs) have largely replaced VTVMs, but they can still be found in some older electronics development labs and hobby benches.

Please Thank NP Technologies for Supporting RF Cafe

NP Technologies designs and manufactures solid state broadband linear RF power amplifiers for commercial, military, medical and industrial applications. RF amplifiers range 10 kHz to 3 GHz in frequency and power levels exceeding 1 kW.

Standard products can be quickly modified to your specific requirements. Full custom requests are welcome. Our team of RF Engineers have over 20 years in the field and are dedicated to providing the best in value, performance and reliability.

The Missed Exam

This is another item that appeared in the December edition of a local publication by The Good Life Press.

"Introductory Chemistry was taught at Duke University for many years by professor Bonk. One year, two guys took the class and did pretty well on all the quizzes and mid-terms - so much so that going into the final, they each had a solid A. These two friends were so confident going into the final that the weekend before finals week, despite the Chemistry final being on Monday, they decided to go to the University of Virginia to party with some friends.   They did this and had a great time. However, with their hangovers and tiredness, they overslept all day Sunday and didn't make it back to...

Income Disparity and CEO Pay Who's to Blame?

I am not of the Occupy Wall Street (OWS) mindset, but an honest assessment of the income disparity between the Haves and Have-nots has indisputably increased considerably in the last decade or so. A recent report by the good folks at EE Times culled data from sources like Roosevelt Institute, IC Insights, and the AFL-CIO to present the rather shocking reality of modern day global caste systems (my characterization) firmly in place. In summary, average pay for 2012 including salaries, bonuses, perks, stock awards, stock options and other incentives for CEOs of the U.S.'s 327 biggest companies was $12.3 million. By comparison, the 2012 average yearly pay for the private sector was $44,300 per the Social Security Administration, and for government employees it is $78,500 (77% higher than private sector). It leaves me conflicted where on the one hand...

AWR Awards Prizes for 2013 Xidian U. Design Competition

AWR Corporation, the innovation leader in high-frequency EDA software, announces the winners of its 2013 Xidian University student design competition, held this autumn in Xi'an, China as part of the company's global Student Design Competition Program. The Xidian competition was announced in June of this year and resulted in dozens of high quality designs being submitted. The winners were announced during an awards ceremony this November.

What Resume Claims Really Mean

This list of items will help you to interpret resumes submitted by applicants to your company. If you are thinking about including any such phrases on your own resume, be aware that we're all on to you now.

 ‡ My background and skills match your requirements: You're probably looking for someone more experienced.

 ‡ I am adaptable:

    I've changed jobs a lot.

 ‡ I am on the go:

    I'm never at my desk.

 ‡ I'm highly motivated to succeed:

    The minute I find a better job, I'm outta there.

 ‡ I have formal training:

    I'm a college drop-out.

 ‡ I interact well with co-workers:

    I've been accused of...

Thanks to Phase Matrix for Continued Support

Phase Matrix designs and manufactures RF and microwave test & measurement (T&M) instruments and components and is a subsidiary of National Instruments. We proudly manufacture within our facility a wide variety of proprietary microwave hybrid components for use in instruments, including state-of-the-art samplers, mixers, high-performance YIG-tuned filters, and multipliers.

2-Way Radio Systems Department Supervisor Needed

CP Communications, located in suburban Westchester County, NY, is a leading provider of temporary large scale RF and fiber optic systems to the TV and special event industries. We are currently seeking an experienced and very motivated individual to be a supervisor and leader in our two-way radio communications department. The qualified candidate will have a minimum of five years hands on experience, and three years at a supervisory level, building and deploying two-way LMR equipment, infrastructure and systems including multi-channel, multi-site installations with transmitter combining. RF over fiber, voting, radio over IP and wired/wireless backhaul skills are a significant plus. Additionally

Antenna Applications in Two-Way Radio Systems

In spite of the proliferation of cellphones and near ubiquitous communications, there are still many applications that require private 2-way communications systems. Emergency services like police, fire, and ambulance; amateur radio, vehicular dispatch for utilities, delivery and repair services; and anywhere that cellular service is not either available or extremely reliable, cannot rely on cellphones for mission critical needs. There are a lot of legacy 2-way radio system antennas and associated towers still being used and many new installations in place. This article in Radio & TV News gives a good overview of the issues of concern with 2-way radio antennas and towers.

PMI 10-Bit, Programmable 60 dB PIN Diode Attenuator

PMI Model No. DTA-1G18G-60-CD-2 is a non-reflective, 10-bit programmable, 60 dB pin diode attenuator with step resolution as low as 0.06 dB that operates over the frequency range of 1.0 to 18.0 GHz. This model is compact in size measuring only 2.0" x 1.81" x 0.88".

Featured Book December 23, 2013

The Girls of Atomic City: The Untold Story of the Women Who Helped Win World War II, by Denise Kiernan. Sometimes when deciding which book to use for this feature I look at what other RF Cafe visitors have purchased other than ones I recommend. Most items are electronics related, either books or devices, but occasionally titles like this appear and are relevant enough to use for the Featured Book (lots of great photos). "At the height of WWII, Oak Ridge, TN, was home to 75,000 residents, consuming more electricity than New York City. But to most of the world, the town did not exist. Thousands of civilians - many of them young women from small towns across the South - were recruited to this secret city, enticed by solid wages and the promise of war-ending work..."

Useful Electronics Articles

Here are a few of the latest circuit design and theory articles from electrical engineering websites.

 • Phase Noise and the

   Y-Factor Noise Figure

 • Use a Heated Diode as

   a Flow Sensor

 • H-Bridge: Black Box Or

   Are Details Important?

 • Marketing for Engineers

 • The Future of Interposers

   for Semiconductor IC

   Packaging

 • O-Scope Stop-on-Trigger

 • EMC Questions Answered

 • Do You Know Your

   Connector Basics?

Merry Christmas
from RF Cafe

Thanks once again for helping to make RF Cafe a success. I truly appreciate the support of advertisers and visitors. Your inputs are always welcome. Here are a few of my favorite Christmas music videos. They include an eclectic mix of Cloverton (new for 2013), the Trans-Siberian Orchestra, an unlikely duet sung by Bing Crosby and David Bowie, and Casting Crowns. Watching the instruments being played really enhances the effect of the song.

Skyworks Intros High Linearity, Active Bias, LNA for Cellular

Skyworks Solutions has introduced a 0.7-1.2 gigahertz, single-die cascode, GaAs, pHEMT LNA for cellular infrastructure applications such as tower-mounted amplifiers, remote radio units, repeaters, and base stations. The new LNA offers very low noise figure and high linearity along with excellent return loss and gain flatness in a small 2x2 mm, no lead plastic package. On-die active bias design of the SKY67111-396LF ensures consistent performance and enables unconditional stability with a 5V supply

Notable Tech Quote

Hofstadter's Law: "It always takes longer than you expect, even when you take into account Hofstadter's Law." - Douglas Hofstadter (hat tip to Gary S.)

Strategy for C.O.D Service

Deadbeat customers have been a problem since time immemorial. Said dirt bags ask you to perform a service and/or provide a product and then either try to cheat you out of full payment or refuse to pay at all. Back in the days when repairmen made in-home visits for radio and television sets, evidently the problem could be really bad. Art Margoli wrote this article for Radio & TV News describing methods he devised to handle, and most importantly avoid, uncomfortable situations and stave off ugly confrontations with customers. One such scheme was to have customers sign a "cognovit note," which is an extraordinary document by which a debtor authorizes his or her creditor's attorney to enter a confession in court that allows judgment against the debtor. Of course litigation would probably cost more than the bill was worth and therefore would not likely be pursued...

An Atomic Pocket Watch Hoptroff No. 10

If you have ever dreamed of having your own atomic-driven pocket watch, too bad, you'll have to wait a little longer. It's not that none exist, it's that only 12 will be made at this time (pun intended), and I'm guessing they're all spoken for - you probably couldn't afford one, anyway. How much for this masterpiece of horological precision? Maker Hoptroff Ltd. isn't saying. "Big deal," you might say, "I have clocks synched to the WWVB signal from NIST's laboratory in Boulder, Colorado." This watch does NOT use that signal; the No. 10 watch has its own onboard ovenized cesium atomic standard. The watch face is so covered with dials and pointers (28) that you have to look for the actual clock part - akin to modern cellphone that has so many...

Science & Engineering

** Christmas Crossword **

 Have a Merry

 Cruciverbalist's

 Christmas!

 (only tech words & clues)

Skyworks Introduces Isolator for Wireless Infrastructure

Skyworks Solutions, Inc. introduces a 2110-2170 MHz single junction, robust lead isolator in an industry leading, small footprint, 11 x 11 mm surface mount package. The SKYFR-000727 is ideally suited for various wireless/cellular infrastructure applications including small-cell designs where space constraints exist. Designed for automated SMT placement, the isolator's insertion loss is less than 0.30 dB over an operating temperature range of –40 °C to +100 °C.

JyeBao Expands Line of Rotary Joint SMA Connectors

Jyebao, a vertically integrated company that designs and produces its RF products in house all the way from raw material to the end product, introduces a line of multi-directional coaxial connectors and adapters. Multi-directional adapters are used to facilitate coaxial cable routing. Jyebao's patented multi-directional adaptors permit smooth rotational movement around two axis allowing the adaptors to move in virtually any direction. SMA plug to SMA jack, SMA jack to SMA jack, and SMA plug to SMA plug multi-directional adapters offer low loss and low VSWR at all rotational angles.

The Day Before Christmas December 1935 QST

I saved this poem from the December 1935 edition of the ARRL's QST magazine for now since it might be the last day of work for the year for many people. "The Day Before Christmas" was penned by radio amateur Robert H. Votaw after the manner of the classic "The Night Before Christmas." It is rare to see such a poem printed in a technical magazine these days, but it was fairly common back in the day. To wit: "Ravin" (1942), "Power Supply" (1944), "Pre-Radio" (1944), "A Radioman's Nightmare" (1945).

Prism Microwave Uses AWR for RF Base Station Filters

Prism Microwave, a technology leader in RF filtering, relies on AWR's Microwave Office® circuit design software for its cavity filter tuning and optimization, as well as the design of active RF electronics and planar components on PCBs, including LNAs, drivers, PAs, dividers, hybrids, attenuators, oscillators, and planar/discrete filters. “Microwave Office is intuitive to use. Its high quality simulation models enable us to achieve fast, accurate and optimized designs. AWR tools help us to achieve 'Smaller, Lighter and Smarter'

Please Thank Boonton for Long-Time Support

Boonton Electronics is a provider of RF & microwave test equipment including peak and average power meters, modulation & audio analyzers, RF millivolt & capacitance meters, and PIM test sets. Peak power meters have up to 70 MHz of video BW, and 40 GHz of carrier BW. Modulation & audio analyzers provide analog measurements required for radio sets. RF Millivoltmeters use an RF probe system that automatically loads calibration coefficients for measurements to 1.2 GHz.

IEEE JobSite Career Alert Items

A new edition of the IEEE JobSite career tips is out. If you are not a member or don't receive their e-mail, here is its contents.

 - Are Your Company's Hiring

   Tactics Unethical?

 - How to Break into the

   Tech Industry

 - Once Fired, Now a Founder:

   How a Tech Leader Rebuilt

   His Career

 - Homegrown Irish Tech

   Sector Thinks Differently

   to Overcome Talent

   Bottleneck

 - Asia-Pacific – Open For

   Business, and Tech Jobs

VidaRF Intros Flange-Mount N/F to SMA/F Adapters

VidaRF now offers flange mount adapters for SMA/Female to N/Female. Rugged construction for repeatability and reliability. Available to ship from stock. Frequency: DC-18 GHz, Return Loss: Min 25dB (1:1.15 VSWR), P/N: ADP-3000-322 Material/Finish: Corrosion resistant 303 stainless steel - passivated, P/N: ADP-3000-322-B Material/Finish: Brass/Nickel, Contact: Beryllium Copper Gold Plated, Insulator: PTFE. Visit VidaRF today to request a quote, view product lines and browse our catalogs.

Anatech Electronics December 2013 Newsletter

Anatech Electronics has published its December 2013 newsletter. As always, it includes both company news and some tidbits about relevant industry events, regulations, and standards. This month, Sam Benzacar offers his views on the subjects of small cell backhaul growth, distributed antenna systems (DAS) growth, and the large amount of potential for interference caused by densely populated small cells.

Reviveaphone™ Salvaging Solution

It has never happened to me, but I have read many tales of woe from people who dropped their cellphones, iPods, Walkmans, etc., into the toilet, a puddle of mud, or a bowl of soup, or else jumped into a pool or the ocean with them in their pockets. The results are usually disastrous, with an expensive repair or replacement bill ensuing. Standard device warranties do not cover immersion, and indeed most devices these days contain an indicator strip inside that turns color when moistened, so there's no way to lie your way into free service. The well-known, but dubiously successful trick of embedding your device in a bowl of white rice to absorb the wetness is only good if you happened to drop it into a glass of demineralized water - something not typically found in a toilet bowl or lake. Sometimes if you...

Digital Filters and Maintaining Your Yard - Related?

Barry Dorr has a unique article on the EDN website titled, "The Relationship Between Digital Filters and Maintaining Your Front Yard." In it, he models the feedback system in play for him that uses critical input from his wife and neighbors regarding the perceived quality of his lawn to modulated the amount of work he puts into its maintenance, which results in an acceptable steady-state level of lush greenness. In the process, you learn a little about digital filter design. BTW, his dog's name is the same as the Bumstead dog's name. Enjoy.

Thanks to Sunshine Design Services for Support!

Joe Cahak has more than 25 years of design engineering and test engineering experience. Specialties include hardware, CAD and software design with extensive capabilities in process automation, database programming, & graphics. Experience includes hardware, bench and rack design, environmental, special fixturing, test interfaces, signal processing, project management, device control functions, and LabVIEW automation.

Elimination of Zero & Cal from Power Sensor Measurements

Orwill Hawkins, of LadyBug Technologies, submitted this short note on the advantages of modern power sensor circuit techniques for eliminating the need for internal zeroing & calibration. Sophisticated factory calibration and a smart sensor allows fully qualified operation across all rated power and temperature ranges. 

Nixie Tube Mania - A Speedometer and a Chess Set

Some things just shouldn't be done, like converting a World War II era Douglas DC-3 airplane's engine from its original twin multi-cylinder radials to jet-engine-powered turboprops; it violates nature's rules. Another example might be installing a digital speedometer in a vintage pickup truck. I say 'might' because thanks to Luke Miller's ingenuity, his 1953 International pickup truck - indeed the world - now has a proven plan for a GPS-driven, two-digit speedometer featuring a Nixie tube numerical display. A two-part article on the EE Times website provides the theory of operation and the details for constructing the Nixie tube speedometer. Why GPS-driven, you might ask...

PMI Intros 2 to 18 GHz Low Noise Amplifier

PMI Model No. PE2-28-218-5R0-12-15-SFF is a 2.0 to 18.0 GHz, low noise amplifier that provides 24 dB min of gain. The noise figure is 4.5 dB max and offers an OP1dB of 14 dBm min. The operating voltage is +15 VDC and the current draw is 200 mA max. The unit is supplied with removable SMA(F) connectors in our standard PE2 housing.

Please Visit Fotofab in Appreciation of Their Support

The good folks at Fotofab have been helping to deliver RF Cafe to you since 2009. Fotofab was founded in 1967 to offer the cost and delivery advantages of photochemical machining - including RF / EMI shielding enclosures - to manufacturers of electronic and electrical equipment for high tech industries - aerospace, microwave, automotive, computers, communications, medical and controls, to mention a few of the most prominent.

Hittite's New 24 dB Power Detector Covers 71 to 86 GHz

Hittite Microwave Corporation has announced a new E-band MMIC power detector that is ideal for communications systems, test equipment, sensors and general purpose RF detection over the 71 - 86 GHz frequency range. The HMC7447 power detector provides a linear output voltage over a -0.5 to +23.5 dBm input power range with low insertion loss of 0.45 dB and typical input return loss of only 19.5 dB. Ideal for monitoring transmitter operation or enabling closed loop transmitter output power, the detector exhibits excellent sensitivity and a frequency response of ±0.2 dB over the 71 to 86 GHz frequency band. The HMC7447 power detector also provides excellent repeatability and flat performance over varying temperature and output load variations.

Featured Book: Digital Waveform Generation

Digital Waveform Generation, by Dr. Pete Symons. This overview introduces powerful, flexible and practical digital waveform generation techniques, enabling the design of bespoke digital waveform generation systems from scratch. Including detailed hardware design examples and downloadable Mathcad models created for 'what if?' design scenarios, this is essential reading for professional members of the digital signal processing community. Peter Symons is a professional engineer with over 30 years of experience in the design of digital and analogue signal processing systems and is Chief Engineer at Avalon Sciences Ltd.

Many Thanks to Noisecom for Long-Time Support!

Noisecom has been a leading provider of RF & microwave noise generating equipment used in commercial & military applications since 1985. We provide noise diodes, calibrated noise sources, jitter sources, cryogenic noise standards, and computer controlled instruments for either precision C/N, or broad band white Gaussian noise. Noise Com provides off the shelf as well as custom designed noise testing solutions.

National Bureau of Standards' Role in IGY

The International Geophysical Year (IGY) ran from July 1957 through December 1958 and was designed to promote cooperation between countries in the earth sciences realm of research. In all, 67 countries participated in various IGY projects. China declined involvement based on objections to Taiwan being involved, arguably perpetuating its people's languishing behind the Iron Curtain of Communism much longer than it otherwise would have. Global studies were carried out for the aurora and airglow, cosmic rays, geomagnetism, gravity, the ionosphere, longitude and latitude determinations, meteorology, oceanography, seismology, and solar activity. It was during this period that the USSR launched Sputnik and the Van Allen radiation belts were discovered. This article reports on the radio-communications-related...

Characterization of Satellite Frequency Up-Converters

Rohde & Schwarz has published a really nice tutorial (aka app note) on how to set up and measure vital parameters on satellite upconverters. The nice thing about this article is that it not only goes into great detail in how to use the many specialty features of the company's network and signal analyzers and signal generators, but it also spends a lot of time reviewing the concepts of intercept points, intermodulation distortion, group delay, frequency mixing and conversion, frequency conversion, noise power, compression points, spurious emissions, and more. If you are new to RF upconversion system design, then this is a good place to start your education.

Congrats to October Book Drawing Winner Tom C. !!!

Tom C., of Fredericksburg, Virginia, is the October RF Cafe Book Drawing winner. I was late in picking winners due to all the books being in storage during a household move. Tom wisely selected Conquer Radio Frequency, by Dr. Francesco Fornetti. Dr. Fornetti graciously donated a copy for the contest. Conquer Radio Frequency was used as the basis for an RF Cafe Quiz.

Babcock Awards R&S HF Military Messaging Contract

The R&S MMHS message handling system from Rohde & Schwarz will be an essential part of the UK Ministry of Defense's naval communications network at their Forest Moor, Kinloss and overseas sites. The contract will be part of the UK MoD's defense high frequency communications service project (DHFCS). DHFCS is a public-private partnership (PPP) that was awarded to Babcock in 2003 for a 15 year period. The purpose of the project is to deliver strategic beyond-line-of-site high frequency (HF) and low frequency (LF) communications services

everything RF Intros GPS/GNSS Antennas and Modules

everything RF, the leading online website for RF & Microwave products, has announced the release of a section dedicated to GPS/GNSS – The section currently covers GPS Antennas and GPS Modules from over 25 companies, and provides a parametric search tool that will help you narrow down on the products by frequency band, supply voltage, gain, noise figure and a number of other parameters. This is the first of series of application sections that are planned on everything RF. Coming up shortly will be sections for Bluetooth, WiFi, RFID, CATV and a number of other applications. 

Notable Tech Quotes Dr. Edward Teller

"[W]hat do you think you get more radiation from, leaning up against an atomic reactor or your wife? ... I don't want to alarm you, but all human beings have radioactive potassium in their blood - and that includes your wife. This reactor may have more radioactivity, but much greater shielding. If you compare the two for radiation, you get just a bit more from Dresden III than from your wife." - Dr. Edward Teller ("father of the hydrogen bomb") at Atomic Energy Commission hearing concerning Dresden III reactor in Illinois.

One Small Step for Synchronization

In this latest installment of EDN's "Tales from the Cube" series, electrical engineer Larry Baxter recounts his experience as a neophyte circuit designer for a numerical display on the Apollo 11 project and how it helped decades later when working on a dielectric-paper photoprinter circuit. It involves a high-voltage signal generator and the importance of synchronizing system processes to minimize noise and facilitate testing. A lot of good lessons are crammed into this one example of how being creative and having the ability to get the job done on your own is a good thing, but having access to and heeding the learned guidance of senior engineers can save a lot of trouble down the line and result in a superior product to boot. My interest, of course, was immediately piqued to the Apollo program, but the story is very much worthwhile reading for any designer.

Please Thank Rohde & Schwarz for Continued Support

Rohde & Schwarz is one of the world's leading manufacturers of test & measurement, communications and broadcasting equipment. With more than 8700 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. Vector Signal Generators. Analog, RF, microwave, and digital signal generators with a variety of frequencies, standards, modulations, and functions at up to 43.5 GHz.