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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).

What is a Servomechanism?

After Class: What is a Servomechanism?, April 1959 Popular Electronics - RF Cafe Servo-mechanisms 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.

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...

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

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.

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 - RF Cafe 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...

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...

Crossword Puzzle
Nov 1960 Electronics World

Crossword Puzzle - Electronics & Other, November 1960 Electronics World - RF Cafe 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.

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 Coaxial Switches, Dow-Key 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.

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...

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 Nova Microwave Drop-In Circulator 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.

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...

A Few Useful Articles

A Few New Articles (December 11, 2013) - RF Cafe 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

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, Kete Microwave Circulators & Isolators 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.

RF Cafe is Back in Full Swing
- from Alpena, Michigan

RF Cafe Is Back in Operation in Alpena, Michigan! - RF Cafe 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...

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.

Anatech Intros Duplexer, BPF,
Isolator, & Directional Coupler

Anatech Electronics has released new designs for a 902 to 928 MHz cavity bandpass filter, an 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.


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