Homepage Archive October 2013

Project Cyclone

Increasing women's roles and interest in STEM (science, technology, engineering, mathematics) careers has been a major effort by schools in the last couple decades in an attempt to 'remove barriers,' both real and perceived, inhibiting entrance into the fields. There are still many realms of STEM that women have avoided, but computer programming and mathematics are examples their representation having seen steady increases. Dr. Frances Bauer can be seen in this 1955 Popular Science story on Project Cyclone, which reports on her role programming what was at the time one of the largest computers in the world. Her work ran the gamut between civil engineering on bridge projects to predicting missile flight paths for the military. You might recall the U.S. Navy's Grace Hopper, who is credited with coining the term "bug" for computers.

AWR Exhibits at

COMCAS and IME 2013

AWR Corporation, the innovation leader in high-frequency EDA software, exhibits at COMCAS 2013 and IME 2013 in Israel and China the week of October 21, 2013.  At each show, the latest release of Microwave Office, Visual System Simulator, Analyst, AXIEM, and Analog Office for the design of MMICs, RF PCBs, RFICs, microwave modules, communication systems, radar systems, antennas and more will be showcased. Specific software demonstrations and lecture presentation include: MWO design environment, design Analyst 3D FEM EM simulation featuring a preview of V11, VSS featuring an enhanced radar library and novel radio frequency planning wizard, RFP AWR Connected to National Instruments. 

The Basics of

Digital Signal Spectra

Here is a short primer by Daniel Chow on the basics of digital signal spectra (EDN website). It begins with the Fourier transform of a single rectangular pulse and progresses through the spectrum of a series of data pulses and of non-rectangular pulses.

Electronic Treasures of the

Sarnoff Collection: IEEE

RCA and the name David Sarnoff seem to be showing up a lot lately, at least in the venues I travel for technical reading. I don't see particular dates mentioned that make this the anniversary of anything related. Ironically, this mention of the two names together adds to the phenomenon. The October 2013 edition of IEEE's Spectrum magazine has a nice spread titled, "Electronic Treasures of the David Sarnoff Collection." RCA, the Radio Corporation of America, was founded in 1919 in Princeton, New Jersey (home base of Mr. Einstein, amongst other notables). David Sarnoff, chairman of RCA, was the son of a Jewish immigrant. Although neither a scientist nor an inventor himself, Sarnoff established a record of ambition and business savvy from a young age - although he was an accomplished telegraph operator (participated in the rescue efforts of the Titanic)...

Please visit KR Electronics

in Appreciation of Support

For over 40 years KR Electronics (an RF Cafe supporter since 2009) has designed and manufactured high quality 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. All the standard topologies are supplied along with diplexers, linear phase, group delay equalizers, and many custom designs.

Carl and Jerry: Ham Radio

Here is another exciting episode of the sleuthing adventures starring Popular Electronics' tech savvy teenagers, Carl and Jerry. The Hardy Boys of electronics are the creation of author John T. Frye, who created short story adventures for many years - long enough to at one point require a major modification in their appearances to reflect more modern attire and eyewear. This particular adventure begins with Carl considering whether his ham radio hobby is more useful from its technical aspects or its social aspects.

everything RF Intros New RF &

Microwave Products at EuMW

The European Microwave Week is the largest Event for the RF & Microwave Industry in Europe. This year it is being held in Nuremberg, Germany from the 6th to the 11th of October. There are over 200 Companies that are taking part in the exhibition here. Today's newsletter lists some new products that have been announced this week at the EuMW 2013.

Electronics for Tomorrow

Cooling devices based on the  Peltier effect were first demonstrated by French physicist Jean Charles Athanase Peltier when he noted the presence of heating or cooling at an electrified junction of two different conductors types (opposite of a thermocouple). Widespread commercial use depended on finding efficient materials that could be produced inexpensively. Music synthesizers, to be practical, needed to await the availability of miniaturized electronics like transistors and memory elements. Light amplification similarly depended on affordable sources to be anything more than a laboratory curiosity. Fortunately, by the mid 1950s such entities were becoming reality. This article reports on a few of those items.

Excel 2013 Bible

RF Cafe Featured Book

Excel 2013 Bible, by John Walkenbach. Engineers still rely pretty heavily on spreadsheets for day-to-day work. The full-featured simulators are invaluable for detailed simulations, but often are severe overkill for a quick calculation. Known as "Mr. Spreadsheet," Walkenbach shows you how to maximize the power of Excel 2013 while bringing you up to speed on the latest features. This perennial bestseller is fully updated to cover all the new features of Excel 2013, including how to navigate the user interface, take advantage of various file formats, master formulas, analyze data with PivotTables, and more.

X-Ray Inspection

X-ray inspection capability is a vital tool not just in medicine busigat in industry. During my tenure with a major cellphone power amplifier company as an RF Applications Engineer, I relied heavily on x-ray imaging for many of the teardown reports that I wrote on competitors' products. It included everything from determining metal layers in integrated circuits to deducing multi-layer ceramic PCB routing lines and distributed components to just getting a quick look inside a shielded enclosure without needing to disassemble it. A skilled x-ray technician can make a huge difference in the quality of information that can be gleaned from the images since angle, power level, and focusing takes a deft touch. My first experience with using x-rays for inspection was while doing automated test system design for production base station equipment companies. Very stringent PIM...

Notable Tech Quote

"If something cant be explained off the back of an envelope, its rubbish." - Richard Branson, Virgin CEO

Many Thanks to SigaTek

for Continued Support!

SigaTek microwave specializes in high quality, high frequency microwave communication components up to 60 GHz. As a pioneer supplier of microwave RF components, the main products include directional couplers, bias tees networks, power dividers/combiners, 3 dB hybrids 90° and 180°, microwave mixers, frequency doublers, load terminations, and coaxial connectors and adapters.

Science & Engineering

Crossword for October 13

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.

How to Solder

Proper soldering is almost as much of an art form as it is a technical skill. Having been through numerous soldering classes in my career, starting with electrical vocational courses in high school, then again in USAF technical school, and other times while working as a technician and engineer, I always exercise care in making solder joints. Proper preparation - including both tinning of mating surfaces and a means to prevent the joint members from moving during cool-down - is of utmost importance for assuring a nice, smooth, shiny joint with just the right amount of solder. Lead-free solders do not tend to produce the level of shininess as do the good old 60-40 type tin-lead solders, but you can still make a nice looking joint. This might be more information than you want to know about me, but I even strive for perfection in solder joints in copper pipes and fittings used in plumbing work. Call me a masochist, eco-villain, or worse, but...

Triad RF Systems and

DCH Systems Join Forces

On May 1st, 2013, DCH Systems, EIN 20-4638136 and Triad RF Systems, Inc., EIN 27-3907731, merged into one entity with the Triad RF Systems, Inc. name surviving. Triad RF Systems is fully owned by three (3) partners: Dean Handrinos, Steve Barthelmes, and David Campbell. Triad RF Systems, was formed with the objective to solve the problem of high power amplifiers (HPAs) being the Achille's heel in most RF radios. We have solutions for integrating high performance HPAs into sophisticated RF subsystems and systems without sacrificing efficiency and linearity. Triad RF Systems serves all areas of the RF and Microwave industries including military, satellite and commercial communications.

Audio Quiz

from Popular Electronics

There are a lot of audiophiles in the RF Cafe audience, so this 10-question quiz about audio topics from Popular Electronics should prove useful. It covers not just the physical aspects but also some simple electronics concepts, like decibels of gain, crossover networks, push-pull amplifiers, etc. Enjoy.

PMI Intros 1 to 40 GHz Ultra-

Wideband Low Noise Amplifier

PMI Model No. PEC-42-1G40G-20-12-292FF is a 1.0 to 40 GHz, ultra-wideband low noise amplifier that provides 42 dB of gain typically with a typical noise figure of 5.5 dB. The OP1dB is typically +22 dBm (1.0 to 18.0 GHz) and +19 dBm (18.0 to 40.0 GHz). The maximum input power rating is +17 dBm CW and the operating DC supply is 550 mA at +12 to +15 VDC. This unit is supplied in a package measuring 1.37" x 1.0" x 0.6" with 2.92 mm female connectors.

Many Thanks to Alliance Test

Equipment for Support!

Alliance Test is a trusted source providing sales, rentals and leasing of refurbished electronic test and measurement equipment to the R&D, manufacturing and quality assurance industries. We carry a full range of used test equipment from manufacturers such as Agilent, Ando, Anritsu, Fluke, HP, Keithley, Lecroy, Rohde & Schwarz, and Tektronix. Recover 30%-40% more on your idle test equipment rather than selling to a dealer.

AWR & NXP Release UWB

Doherty Amp Reference Design

AWR Corporation, the innovation leader in high-frequency electronic design automation (EDA), announces  that NXP Semiconductor's ultra-wideband (UWB) Doherty reference design is now AWR Microwave Office design environment ready. The updated release features NXP's BLF884P and BLF884PS transistors for ultra-wideband Doherty power amplifiers operating from 470 to 806 MHz and a 70 W DVB-T UWB LDMOS reference design using NXP's patent-pending architecture capable of operating over an ultra-wideband spectrum in the UHF broadcast spectrum.

Sherlock Ohms: Case of the

Slighted Newbie Engineer

Sherlock Ohms is a regular feature of the Design News website where readers submit anecdotes from their on-the-job experiences. There has been a tendency lately in this column and, to a lesser degree, in the similar Tales from the Cube column for situations involving newer, less experienced engineers being frustrated by the domineering attitudes of some senior engineers. In contrast, I cannot recall an instance of a story where the senior engineer dumps on stupid actions of a newbie. Maybe doing so is considered bullying or akin to a guy hitting a girl. Regardless, all the stories in both columns are good for instruction...

Interface Coiled Tubing

Load Cells

Coil tubing load cells are used for measuring the insertion force of small diameter (typically 0.5 to 4.5 inch) stainless steel tubing that is inserted into the borehole / wellbore at the wellhead. A borehole is any hole drilled for the purpose of exploration or extraction of natural resources such as water, gas or oil where a well is being produced. The coil tubing (CT) is usually installed when the well, which has been drilled, is deemed ‘viable' and will produce the natural resource in a productive and economic manner. Coil tubing provides intervention allowance of vertical, horizontal, highly deviated, and live wells(1). Adding

How to Read and Understand

an Antenna Data Sheet

A white paper has been published by Linx Technologies titled, "How to Understand an Antenna Data Sheet." Author, Shawn Hogan, VP of Engineering, writes, "The information on an antenna data sheet is nothing short of overwhelming. It can be difficult to maneuver through to select the best antenna for your design. There are several factors to take into account when looking at an antenna data sheet including: monopole vs. dipole antennas, the electrical parameters, counterpoise, gain and radiation pattern. Our goal is to break down these features so you can use that knowledge to discover advantages and disadvantages of different antennas as they relate to your specific application..."

RCA Cunningham Radiotron Ad

Have you seen the new national advertising campaign where Freescale (formerly Motorola) is using big name celebrities to sell their cellular base station power transistors? Scarlett Johansson and Ashton Kutcher are up on a tower along with man-and-woman-on-the-tower smartphone users discussing how much better their phones work now that the service provider switched to base transceiver stations that use Freescale LDMOS RF power transistors. Of course you haven't seen the ad because it would never be produced and marketed. The very concept is ridiculous, you might say... unless you happened to see advertisements like this one for RCA's Radiotron vacuum tubes from the 1930s. In it, none other than Bing Crosby...

Advanced Test Equipment

Rentals October Newsletter

Advanced Test Equipment Rentals just issued their Tech Talk newsletter for October 2013. It includes hot topics in the tech news world and highlights of new or special function test equipment they have available. Please click on the thumbnail to access the original versions.

Many Thanks to Hittite

for Continued Support

Hittite Microwave is an innovative designer and manufacturer of high performance integrated circuits, modules, subsystems & instruments for technically demanding digital, RF, microwave and millimeter wave applications covering DC to 110 GHz. The Company's standard and custom products apply analog, digital & mixed-signal semiconductor technologies used in a wide variety of wireless / wired communication and sensor applications for automotive, broadband, cellular infrastructure, fiber optics, microwave & mm-wave comms, military, test & measurement, and space markets.

Unique Solutions Supported

by Empower HPAs

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 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 SATCOM solution delivers 2 kW P1dB (CW, digital modulated signal) in L-Band and a companion product delivers 800 W P1dB (CW, digital modulated signal) in S-Band. The 2 kW L-Band HPA is a GaN based design and housed in an amazingly small 5U chassis.

Federal Circuit Ponders

Abandoning De Novo Review

Being involved as an Expert Witness for a court case involving product liability and/or IP ownership or infringement is a unique experience according to those who have been through it. Having competent and renowned legal representation is paramount to success, particularly if your opponent is well equipped. IMS ExpertServices is a law firm specializing in expert witness cases. Every month or so they send me an article about specific court cases that could be of interest to RF Cafe visitors. This particular article is titled "Federal Circuit Ponders Abandoning De Novo Review." Overturning precedence is notoriously difficult since doing can have ramifications that reach way back in time and can trigger appeals to long-settled court cases. This potential for the overturning of a patent infringement case from 1998 based on how it was constructed is predicted to trigger significant consequences for past and future litigation...

Thanks Once Again to Vida RF

for Continued Support

The goal at Vida RF is to design and manufacture a reliable and cost-effective RF / Microwave Component that fits each customer's individual application. Vida RF has the capability to produce large volume as well as quick turnaround for your custom designs, and they will provide the highest standards of quality products, competitive prices, quick turnaround and exceptional customer service. RF connectors, cable assemblies, power dividers, RF adapters & terminations, fixed attenuators, dust caps, directional couplers, and i isolators & circulators are among their offerings.

Music to the Ears

of an Engineer

We technically oriented types often think of those with an  artsy-fartsy bent as ones who run for the tall grass when topics of science and/or mathematics arise. Other than engineers, scientists, financiers, etc., I would say in most cases it is justified - but not always. In the September 2013 edition of Strings magazine, an article titled, "How the Violin Altered Our View of the Universe" appeared where author Paul Stein, a violinist, educator, and member of the Los Angeles Philharmonic, evidenced a very good grasp of science and math principles. The very decision to pen such an article had to have been born of a knowledge and comfort with the aforementioned. A subtitle of, "Physicist & violinist Albert Einstein's cosmic orchestra resonates with the music of the spheres," proves familiarity of Isaac Newton's "Music of the Spheres," (Musica Universalis)...

Featured Book

The Electric Vehicle Conversion Handbook, by Mark Warner, is a guide on how to convert any gas- or diesel-powered vehicle to electric power. Includes ownership advantages, basic EV operation, subsystems, components, basic EV operation, project vehicles, and conversion kits. Motor and battery technology is advancing at amazing rates, so if you don't like the weenie look of today's production electrical vehicles and would rather try your hand at an electric conversion on a classic 1965 Mustang, then this type of resource can be invaluable.

Ponderings on Power

Measurements - RF Cafe

Joe Cahak, owner of Sunshine Design Engineering Services, has submitted another fine article for posting here. Joe has many years of automated RF testing experience to leverage when writing this paper on the basics of power measurement. A power measurement is a scalar quantity and is a measure of power detected. These measurements can be made a variety of ways. Most of us are familiar with the notion that voltage (volts) multiplied by current (amps) is power (watts) and power multiplied by time is energy. At DC or low frequencies these power measurements from the current or voltage is relatively easy and not very complicated...

RF Cafe Quiz #54

Microwave Mixer Technology

This quiz is based on the information presented in Microwave Mixer Technology and Applications, by Bert Henderson and Edmar Camargo. Some of these books are available as prizes in the monthly RF Cafe Giveaway. Based on a review of over one thousand patents on mixers and frequency conversion, the authors have written a comprehensive book for mixer designers who want solid ideas for solving their own design challenges. Many of the important and most interesting patents and related circuits are discussed in the several application oriented chapters.

Notable Quote

"...I have always maintained that, excepting fools, men did not differ much in intellect, only in zeal and hard work; and I still think there is an eminently important difference." - Charles Darwin, letter citing R. Pearson (1914-1930) in The Life, Letters and Labours of Francis Galton, TodayInScience

British Radio Hoax

Traps "Pirate" Listeners

When you think of radio pirate, most likely what comes to mind is a rogue, unlicensed transmitter that is re-broadcasting copyrighted material, syndicated shows, etc., on radio or television. Nowadays that would also include the Internet as a medium. Did you know that, at least decades ago, the British government (and maybe others) charged citizens a fee for listening to broadcasts on their household radios? That's right, if you wanted to listen to the BBC, you would kindly remit a fee of 10 shillings per year. Otherwise, you were apt to have government inspectors descend upon you and padlock your radio set - or collect the requisite 10 shillings on the spot. After a growing number of suspected dishonest British subjects finally exceeded the reasonable level of tolerance of the government, a clever scheme was devised to trick evil citizens into divulging their nefarious crimes...

Thanks to Rohde & Schwarz

for Their Continued Support!

Rohde & Schwarz is one of the world's leading manufacturers of test & measurement, communications and broadcasting equipment. Network analyzers, signal analyzers, spectrum analyzers, and signal generators for analog, RF, microwave, and mm-wave signals with a standards, modulations, and functions available at up to 43.5 GHz. Digital Oscilloscopes for RF, analog, mixed signal & digital integration, and software development & production up to 4 GHz BW. RF Power Meters up to 110 GHz.

Inc's 2013 Survey

of Entrepreneurs

Most people, according to surveys, consider starting their own businesses at some time during their working years. The risk of failure and the cost of startup are what prevent most elsewise entrepreneurs from taking the leap of faith in their own abilities. Not everyone is cut out for running a business whether it be a one-person venture or a conglomerate with a payrolls of hundreds. Knowing and heeding your own limitation in deciding to remain under the employ of another company is as virtuous and sound a reason for dismissing thoughts for self-employment as is having the knowledge and will to strike out on your own. A lot of business are started on the sideline while being employed fulltime in a regular job. Indeed, that was RF Cafe's origin. It wasn't until I had confidence that I could subsist on RF Cafe's revenue level that I left the security of the best engineering job I ever had to tend to the website full-time (at a substantial reduction in pay, I will add). Every year or so, Inc magazine does a major poll of successful entrepreneurs to find out what motivates them (2013 Inc 5000)...

Physics & Engineering

Crossword for 10-6-2013

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.

Many Thanks to Nortec RF

for Continued Support!

Nortec RF has more than 22 years of experience designing power combiners and dividers, directional couplers, hybrid couplers, filters, and power amplifiers. Their research and development group and engineering team constantly introduces new, top of the line products into our RF and microwave components product line.

Fairview Microwave Offers

Schottky Diode Detectors

Fairview Microwave announces a new line of in-stock Zero Bias Schottky Diode Detectors. Diode Detectors are used to rectify an RF input signal to a proportional DC output voltage. Applications for Zero Bias Schottky Diode Detectors include precision and lab testing equipment, as well as transmitter, power and signal monitoring systems. Fairview's new line of Zero Bias Schottky Diode Detectors comes in several different connector configurations and frequencies in the 0.01 to 26.5 GHz range.

1-800-318-2596

That is the phone number for signing up for America's new Affordable Care Act. Do you believe it is just a coincidence that it spells out "1-800-F1U-CKYO?" I kid you not. From what information I could find, the lowest cost plan for Melanie and me is the Bronze plan, which will cost $9,481 with a $12,700 deductible (only 60% coverage after deductible is met). My current private plan through BCBS with a $7,000 deductible (90% coverage after deductible is met) is only $4,971. So, beginning in January 2014 that represents a 91% increase in cost and a $5,700 higher deductible, plus only 60% coverage after the deductible is met. I do not qualify for any subsidy. To all my fellow Americans that voted for this crap - thanks a lot!

Modern Radio Practice in

Using Graphs and Charts

Using charts and nomographs to solve calculations is not as common in today's world of portable high-powered computers as it was when computers used vacuum tubes or even mechanical gears. One exception might be the Smith chart, especially in the lab or field. You can plug numbers into a programmable calculator or tablet app, but having the solution presented in the form of a number gives you only that - a number. That's usually good enough, but if you are doing troubleshooting or tweaking a design, being able to see how the value got to be what it is by seeing what's around it can be very helpful. The Smith chart is a particularly good example when watching the complex impedance point move around. The more experience you have, the less you need such devices, but newbies...

JobLens™: Nokia's Augmented

Reality Job Search App

Are you in the market for a new job as an intern, part-time, temporary, or full-time worker and are not quite sure how to go about finding out where the kind of employment you are seeking is located? Wouldn't it be nice if you could simply drive or walk around town and any place that fit the bill would be highlighted for you automatically? Nokia has an app for that, and it's called JobLens™. Using what is termed "Augmented Reality," JobLens assimilates a multitude of social networking services like LinkedIn, Facebook, Twitter, Indeed, Here Maps, Windows Live, Salary.com, Zillow, CareerOneStop, Data.uk.gov, Payscale, and other best-in-class content partners along with other location-dependent resources to pinpoint targets for investigation. It might be a little underpowered when looking for an engineering type position...

Radio Fever - Using HF Electric

Fields in Modern Medicine

"My God, man! Drilling holes in his head isn't the answer! Now put away your butcher knives and let me save this patient before it's too late!" Those classic words were uttered by Dr. McCoy in Star Trek IV: The Voyage Home, after Lt. Chekov (promoted from Ensign after the TV series) sustained brain damage as a result of falling from a 'nuclear wessel' when 20th century naval surgeons were about to open his skull to relieve pressure from swelling. Looking at these images from a 1932 article on using radio waves "to produce protective fever in killing germs of a number of diseases." Update: I have been informed that shortwave diathermy is still used in modern medicine! 10 to 30 meters was a popular wavelength band at a power of about 500 watts. The patient's body part to be treated is placed between the plates to act "as a dielectric" while the liquids are heated via induced oscillations similar to how a microwave oven...

Interface – Driven to Perform

To succeed in automotive racing, a commitment is required... a commitment to always ask for more and to never settle for less. Continual improvement is necessary to stay ahead of your competition and win. This drive to be the best is part of Interface's DNA, from our product and service offering to the dedication of our employees. Accurate force measurement is a vital requirement of the automotive industry and in the competition arena, performance demands are pushed even higher. Interface takes great pride in being a leading solutions provider in these applications. Whether it's for NASCAR, IndyCar, or even the amateur level, engineers rely on Interface.

Phenomena Underlying Radio

"Radio apparatus of today, including television, uses practically all of the physical phenomena capable of being controlled by science." That is the opening line of a 1932 article discussing the relatively new technology dealing with the generation AND controlling of electrical charges. Investigators were beginning to develop formulas and physical rules for the behavior of electrons - at least in accordance with the accepted Rutherford-Bohr atomic model. It wasn't until 1929 that Robert Van de Graaff invented his eponymous generator, before which scientists like Volta used an electrophorus (Latin for "electricity bearer") to generate static electrical charges for experimentation by beating a metal disc with an animal skin... 

NuWaves Receives ISO 9001

and AS9100 QMS Certifications

NuWaves Engineering, an international RF and embedded systems solutions provider, announces it has achieved both ISO 9001:2008 and AS9100:2009 Rev C certifications for its Quality Management System by EAGLE Registrations Inc. "NuWaves is excited to join the top tier suppliers in our industry with these highly respected quality certifications," said Jeff Wells, President and CEO of NuWaves Engineering. "It's a testament to our employees and their dedication to delivering quality products and services to our customers each and every day."

Congrats to September

Book Winner Greg F. !!!

Greg F., of Ft. Collins, CO, is the September 2013 book drawing winner. Greg selected Introduction to Antenna Analysis Using EM Simulators. This book was graciously provided by Artech House.

Online Calculators

by Compliance Engineering

Compliance Engineering is an EMC testing and certification facility located in Knoxfield, Australia. They have a few nice online RF calculators that might be useful to you.

-  RF Calculator: Wavelength,

    dBm, dBuV, W, dBuV/m,

    mW/cm², pJ/cm², V & VSWR

-  Radiated Power Calculator:

    ERP, EIRP, dBuV/m, dBm & mW

-  Field Strength Calculator:

   V/m, dBuV/m, dBuA/m, pT,

    dBpT, Tesla, Gauss, A/m,

    mW/cm² & W/m²

Linx Intros TM Series High

Accuracy GNSS Receiver

Linx Technologies is pleased to announce its launch of the TM Series Global Navigation Satellite System (GNSS) receiver modules. At a very small size of 10mm x 10mm, the TM Series GNSS receiver module is a self-contained, high-performance Global Satellite Navigation System receiver designed for navigation, asset tracking and positioning applications of all kinds. Based on the MediaTek chipset, it can simultaneously acquire and track several satellite constellations. These include the United States GPS system, Europe's GALILEO, Russia's GLONASS and Japan's QZSS.

Inrush Current Protection

Using an NTC Thermistor

Thermistor manufacturer Ametherm has three application notes that address the problem of limiting inrush current.

-  How to Stop Inrush Current: Design considerations for inrush current protection of the AC current applicable to switching power supplies.

-  Transformer Inrush Current Protection: A convenient solution to deal with the problem of inrush current exceeding saturation current in transformers.

-  Thermistor Protection for a Precharge Circuit on Lithium Ion Batteries: When a battery is connected to a load with capacitive input, there is an inrush current surge as the capacitance is charging to the battery voltage.

Many Thanks to PMI

for Their Continuing Support

Planar Monolithics Industries (PMI) has been set up to manufacture and market various MIC/MMIC components, supercomponents, and subsystems for applications in telecommunications, terrestrial, satellite, and mobile-radio communications, defense (ECM, ECCM, ESM, radars, and EW), cable-TV, navigation and marine electronics, FAA/DOT-avionics, ground based systems, and microwave landing systems.

Phonebloks

A Personalized Phone

As of this writing, at least 863,790 people believe the concept of a modular, upgradable, personalized smartphone is a good enough idea to invest their support in it. With 28 days left to go, the Phonebloks developers are already at 95% of their crowdfunded revenue goal. As I reported a ways back, while Kickstarter was the first crowdfunding venue to receive wide publicity, there are now many such options for soliciting project startup cash. The Phonebloks team chose Thunderclap. Thunderclap is not actually a crowdfunding source but a 'crowdspeaking' scheme for gathering enthusiasts for your idea. If enough people support your project, Thunderclap will blast out a timed Facebook Post or Tweet from all your supporters, creating a wave of attention... for what it's worth. Phoneblok's concept is based on the belief that the current throw-away philosophy for electronics devices - cellphones in particular - is wasteful not just in terms of money but in terms of...

Skyworks Intros Linear PAs

for LTE and WCDMA Apps

Skyworks Solutions introduces four linear power amplifiers for LTE and WCDMA applications. The fully matched surface mount SKY66001-11 (2110-2170 MHz), SKY66002-11 (1900-2025 MHz), SKY66005-11 (850-920 MHz) and SKY66008-11 (900-990 MHz) modules meet the stringent spectral linearity requirements of femtocell applications with high power-added efficiency. An integrated directional coupler eliminates the need for any external coupler.

Anatech Electronics Intros

3 New Filters & an Isolator

Anatech Electronics has released new designs for a 710-716 MHz / 740-746 MHz bandpass combiner, a 4.4 to 5 GHz surface mount isolator, a 769 to 775 MHz bandpass filter for Public Safety, and a 2500 to 2570/2620 to 2690 MHz cavity diplexer. All can be ordered directly through our AMCrf web store. 

Thanks for Continued Support

from Marvelous Microwave!

Marvelous Microwave is a professional supplier of Microwave/RF components, for WiFi, Cellular, Bluetooth, GPS, DVB-T/S/C, Satellite Communication and related fields. A strong global channel and design group devoted to development and innovation to meet various changeable market needs. We strive for low cost, fast service, best prices, highest quality and "marvelous" service. Attenuators, connectors and cables, amplifiers, filters, and RF switches are among their many offerings.

Featured Book

Electronic Warfare in the Information Age, by D. Curtis Schleher. This is an advanced practitioner's guide to current concepts and threats associated with modern electronic warfare (EW). It identifies and explains the newest radar communications threats, and provides practical, "how-to" information on designing and implementing ECM and ECCM systems. The aim of the text is to help the reader develop ESM systems designed specifically to exploit the vulnerabilities of modern radar. It also identifies and evaluates ESM receiving equipment, and outlines advanced ECM methods, including monopulse deception, coherent radar jamming, and high-ERP generation.

The Internet of Things:

Building Blocks for Wireless

The Internet of Things is a term that is appearing with much frequency these days (e.g., in this article). Akin to 3G and 4G, the definition does not seem to be very well defined; that is to say more subjective than objective. Per Wikipedia's entry: "The Internet of Things refers to uniquely identifiable objects and their virtual representations in an Internet-like structure. The term "Internet of Things" was proposed by Kevin Ashton in 1999. The concept of the Internet of Things first became popular through the Auto-ID Center at MIT and related market analysts publications. Radio-frequency identification (RFID) is often seen as a prerequisite for the Internet of Things. If all objects and people in daily life were equipped with identifiers, they could be managed and inventoried by computers. Besides using RFID...

How We Listen to

Stars and Satellites

If you have never paid much attention to the state of the art in telescopes, then you might believe they consist of either the $99 Tasco jobs in Walmart's toy department or the 200" Hale atop Mount Palomar. You might also think that objects which emit or reflect light in the visible spectrum are the only things studied. You might not know that radio telescopes have been built to detect frequencies ranging from HF all the way up into cosmic rays. Newer telescopes search for gravity waves and even neutrino and 'dark matter' pseudo particles. You might not know that there is a broad selection of optical telescopes for amateur and research grade telescopes and that the line between amateur and research grade telescopes...

Copper Mountain Adds 4 Port

Planar 808/1 to VNA Line

Copper Mountain Technologies releases the new Planar 808/1 vector network analyzer, adding to its full size VNA line. CMT makes high performance PC-driven VNAs at an affordable price point without sacrificing metrological quality. Planar 808/1 is a four port VNA which operates with an external PC, opening a new range of possibilities for users who need highly accurate multiport instrumentation for lab, production, or field use. At just 19 pounds, Planar 808/1 is a more mobile and transportable solution than a traditional bench top unit. This lab quality VNA offers an extensive feature set, multiple data saving options, and is fully programmable for incorporation in automated applications.

Thanks to Asian Circuits

for Ongoing Support

Asian Circuits, with its HQ in Toronto, Canada, and production facilities in China, has emerged as a well known turn-key PCB assembly service provider. Asian Circuits is known for providing electronic manufacturing services, including PCB fabrication, components sourcing, and complete electronic assembly. Our online PCB assembly quote generator can help you estimate the assembly cost of your PCB project. We cater to customers primarily located in the U.S. and Canada.

Linx FM Series GPS Rx Module

for High Position Accuracy

Linx Technologies announces its launch of the self-contained, high-performance FM GPS receiver modules. At just 15x13 mm in size, the MediaTek MT3339-based FM Series gives the module fast lock times and high position accuracy even at low signal levels. Very low power consumption helps maximize runtimes in battery powered applications, such as positioning and navigation, location tracking, marine, and asset management. Simultaneously acquires on 66 channels and track on up to 22 channels. The GPS receiver is completely self-contained and only requires an antenna.

RF & Microwave Magazine

Articles for October

The RF & microwave trade magazines have updated their online articles for October. Here are a few that might interest you.

- Analyzing the Role of Local

  Oscillator Phase Noise in

  Reciprocal Mixing, ACS

- 100W High Power Silicon PIN

  Diode SPDT Switches,

  Skyworks Solutions

- Next Generation Wireless:

  Riding On the Back of

  Millimeter Waves,

  Renaissance

- Measure Vector and Area

  with an Oscilloscope X-Y

  Display, Arthur Pini

- How to Think in dB,

  Eric Bogatin

- Understanding Measurement

  Uncertainties in Spectrum

  Analysis, Bob Nelson

- Evaluate EDA Software for

  a Wireless World,

  Dr. Stephen Maas

- Beyond CMOS Vs. GaAs:

  Pick the Right Technology,

  Matthew Ozalas

Stable Microwave Oscillators

Long before digital communications was widely adopted, there was a great need for stable frequency-determining devices / systems. That is to say, low bit error rates (BER) for digital communications are not the sole motivation for oscillators with low short-term and long-term stability and low levels of jitter. One obvious need for precise frequency control is radar, in order for accurate ranging (the second 'R' in radar) and in the case of Doppler systems, for accurate radial velocity reporting and clutter cancellation. Those capabilities existed long before digital systems came online. Aside from radar, precise frequency was needed in order to reduce guard band width between assigned channel assignments, thereby enabling more broadcast stations (commercial and military) to coexist in an allotted frequency...

How to Be Funny at the Office

"29 Skills Every Founder Needs to Master" is the theme of the November 2013 Inc magazine issue. Topics such as "How to Do More of What You're Good at and Less of What You're Bad At," "How to Take a Fresh Approach to a Staid Old Business," and "How to Really Connect with Customers," are typical. I scanned over a few to see what the entrepreneurial business owners had to say about their experiences that they considered most to be useful. Then, I arrived at the last one, Tip No.29: How to Be Funny at the Office. This I had to read. Something just didn't seem right, though, as I progressed through the story. Take this passage from a Q&A session...

PMI Intros 250 MHz - 8.5 GHz

Low Noise Amplifier

Planar Monolithics Industries (PMI) introduces Model No. PE210R258R515SFFLM Rev. B, a 0.25 to 8.5 GHz, low noise amplifier with a small signal gain window of +9.0 dB to +13 dB.  The noise figure for this unit is ≤4.5 dB max (valid from 0.5 to 8.5 GHz) and offers an OP1dB of +16 dB min.  The operating voltage is +12VDC and the current draw is 300mA max.  The unit is supplied with removable SMA(F) connectors in our standard PE2 housing.

Russian Jamming:

The Electronic Iron Curtain

Whoa! Take a look at the RF feedthrough and lightning arresting choke on the feed line on the original Voice of America transmitter in Munich, Germany. Now that is serious stuff. This story from an early Popular Electronics reports on the extreme lengths to which the Soviet bloc went in order to prevent its countrymen from hearing radio signals broadcast by the Voice of America and other non-state-approved beacons. Quarter megawatt transmitters sent messages of freedom that could be picked up by even the most remote crystal sets that didn't have the advantage of amplification. Ground-wave, sky-wave, and short-wave jamming techniques were employed to ensure the only signal that could be received was a buzz-saw type noise. Not so long ago, and certainly in 1959, America was viewed as a beacon of freedom, both figuratively via word-of-mouth and underground newspapers, and literally via high powered...

Bendix Model 75P6U

1940s Era AM/FM Radio

RF Cafe contributor Bob Davis has added another vintage radio to his collection - a Bendix Model 75P6U AM/FM tabletop radio. More extensive restoration is planned, but for now just replacing all the electrolytic and wax-paper type capacitors put the set into working order.

Featured Book

Challenging the Chip: Labor Rights and Environmental Justice in the Global Electronics Industry, by T. Smith, D. Sonnenfeld, and D. Pellow. I've never been one to shy away from a good argument when it comes to bucking against the ill winds of political correctness. In general, PCness causes the vast majority to suffer for the benefit of a relative few who often assert their 'rights' (real or imagined) to special privilege out of spite and/or self-righteousness. The subject of exploitation of the world's poor and desperate to the advantage of the rest of us bothers my conscience in a conflicted manner. On the one hand I realize that the exploited often consider their new conditions to be better than what they previously endured, but on the other hand there is a moral obligation to not rationalize away our complicity in the matter. The most egregious offenders are those who make a lot of noise about profiting from the misfortunes of said poor while obliviously...

A Lost Art: Wire-Wrapping

For this week's Featured Book, I wanted to find something on wire-wrapping. Although I was not successful at finding a book currently in publication that is dedicated to wire-wrapping, I did find a great page on Wikipedia full of information and great high-res pictures. There are plenty more resources if you do a Google search. Wire wrapping (w/w) used the be a very popular method for prototyping circuits when DIP and SIP packages dominated the electronics landscape. If done properly where wraps were placed on posts in order to make changes easier and where care was taken to avoid crosstalk from long parallel signals runs, w/w was useful at frequencies into the tens of megahertz, even with digital circuits. I personally have wire-wrapped more than a hundred boards both as engineering prototypes and as deliverable assemblies for military equipment. A well-done w/w board...

Google's Mysterious

Floating Data Center

Which came first, the chicken or the egg? The same can probably be asked of Google and the government's (NSA, CIA, FBI, DHS, and various other 3-letter agencies) need for a massive data collection capability that at first glance has the appearance of a benign private company. Even though Larry Page and Sergey Brin undoubtedly developed and built Google without any help from the Fed, their current intertwinings with every facet of government from low level agency personnel all the way up to the prez himself is unquestionable. You don't get that kind of access and wield such influence without giving up something in return - usually your honor and personal motto (in this case abandoning "Don't Be Evil"). We have all witnessed hypocrisy on the part of Google's executives in the form of a pimped-out Boeing 767 aircraft for globe trotting under the guise of eco-warrioring, along with special landing privileges at military installations. Add to that...

Thanks Much to everything RF

for Continued Support!

everything RF is a search engine for RF & microwave components. everything RF lists complete catalogs from various RF & microwave component manufacturers and enables engineers to search through them by specification. There are over 124,463 components listed from more than 281 manufacturers. Download datasheets, request quotes or contact the suppliers for more information via everything RF. Its Fast & Easy!

Notable Tech Quote

"Dual-band." - Response (referring to AM/FM) given by Ham radio operator when ask by policeman in Virginia what type of radio he had installed in his car (hat tip to RF Cafe visitor KA). Virginia DOT requires that "A vehicle displaying Call Letter License Plates is subject to inspection by DMV or any police officer to determine if the operator and the vehicle comply with the requirements." You must "Have operational transmitting and receiving equipment permanently installed in your vehicle." The specific wording requires Tx AND Rx equipment (AM/FM radio is Rx only and therefore might not qualify), but that could just be bureaucratic ineptness. Now thieves on the prowl for mobile rigs know exactly which vehicles to target for a guaranteed payoff. BTW, I also learned while researching details on...

Fiber Optics Amplifier Tutorial

This tutorial should be useful both as an introduction to fiber optic amplifiers and for learning more details on them. We believe that even people already having a substantial experience with fiber amplifiers will find it helpful for deepening the understanding. The focus is on the underlying physics and the resulting technical consequences; we do not simply treat a fiber amplifier as a “black box”, but rather look inside. By RP Photonics Consulting GmbH.

Mozilla Lightbeam - Shining the

Light of Truth on Websites

A couple years ago, Mozilla published an add-on tool called Collusion for monitoring which websites were tracking your movements around the Internet. A follow-on app named Lightbeam, with even greater power, has been released: "Shining a spotlight on online data tracking to help people understand the Web around them." As with Collusion, Lightbeam gives you a picture of all the websites that are notified of your presence on your targeted website. For instance, when you evaluate RF Cafe using Lightbeam, you will discover that Google and DoubleClick (a Google subsidiary) are notified in order to serve pay-per-click banner advertisements. I depend on them to generate revenue for putting food on my table and a roof over my head. To be honest, I have no idea what happens after Google checks in, other than being fairly confident that the NSA is also notified as they are for every click, e-mail, or phone call you make anywhere...

Engineering Crossword

Puzzle for 10/27/2013

This week's crossword puzzle was constructed specially for the good folks in the engineering department of Brigham Young University (BYU). Event planner J.M. wrote to request the use of a crossword, and in response I created one for them. If you have a similar need, I will be glad to do the same for your group if I have the time. Enjoy.

Many thanks to Orbel

Once Again for Support

Orbel Corp. is the leading designer and manufacturer of RF Shielding and EMI/RFI Isolation Products for printed circuit boards and electronic enclosures. Orbel also specializes in thin gauge photo etched metal parts and precision metal stampings made from a wide variety of material options. We manage every aspect of metal stamping from design, prototyping, short to medium runs and high volume stamping.

Spartant Wideband Signal

Generator with USB Interface

Spartant has developed a new line of wideband RF signal generators that have a USB interface. Their initial products include two models: 25-6000 MHz and 25-3000 MHz, both featuring USB for control / power and both having a  +13 dBm maximum output power with phase noise of -106 dBc/Hz @100 kHz offset @250-1000 MHz. As with most USB test instruments, the size is kept small (about the size of a deck of cards) by having the user interface reside in software installed on the user's computer. An Ethernet interface will be available in the near future. Spartant is a 3dea Technologies company.

Loudspeaker Repairs

Anyone Can Make

In today's throw-away society, most people would never consider attempting to repair a speaker if it were to develop a tear or a puncture. Why should you bother when a replacement is so inexpensive? Well, there are several reasons you might want to affect the repair yourself. First, the speaker might be integrated into the system in such a manner that replacing it would be difficult or even impossible. Second, some speakers are actually pretty darn expensive, especially large diameter models and high quality models regardless of size. Third, a replacement might not be available, as with a vintage radio or television. Fourth, maybe you just want the challenge and satisfaction of repairing the speaker rather than adding its bulk to a landfill...

Empower RF Requests Your

Presence at AOC 2013

Empower is pleased to be once again conducting a "live" demonstration of an ultra broadband (20 to 1000 MHz), high power (1 kW CW) amplifier platform which is housed in an industry leading 5U chassis. The fact that we are controlling this amplifier through a wireless connection and highlighting diagnostics and remote control features through an iPad is equally impressive and, we believe, also industry leading. Our live demonstrations throughout 2013 have been well received and, for us, a serious validation of the next generation amplifier platforms we have designed

New RF & Microwave Products

Into at EuMW - everythingRF

everythingRF has issued a newsletter highlighting some of the new items introduced at European Microwave Week. It is the largest event for the RF & Microwave Industry in Europe. This year, 2013, it was held in Nuremberg, Germany from the 6-11 October. There were over 200 companies that took part in the exhibition.

Please Thank JFW Industries

for Supporting RF Cafe

JFW Industries is a world leader in designing and manufacturing of passive RF components and application specific test systems. These components include attenuators, RF switches, and specialized test systems for use in the cellular, telecom, OEM test equipment, medical, automotive, defense, and automated test systems markets. Application specific designs are the cornerstone of JFW's continuous technical advances in RF components

Measuring Peak and Pulse

Power w/USB Power Sensors

As technology and measuring techniques advance, the time eventually comes when continuing to use old methods not only doesn't make sense, but can actually harm your reputation by providing data that cannot be duplicated by customers who long ago adopted the new ways. Orwill Hawkins, of LadyBug Technologies, has written a white paper describing how to make accurate, repeatable peak and pulse power measurements on waveforms using the precision of modern instruments that provide a graphical view of the entity being investigated. USB power meters provide an inexpensive means of obtaining high quality measurements and the benefits of a graphical display environment (on your computer) at a relatively low cost. I particularly like the use of the word 'mesial' in describing the midpoint of a pulse's rising and falling edges.

Measuring Semiconductor

Device Input Parameters

with Vector Analysis

Joe Cahak, of Sunshine Design Engineering Services, has published yet another paper in his series on making RF test measurements. This article will cover a recent test experience that utilized some thinking about the test fixture, the bias requirements and the device mounting and special calibration offsets needed to de-embed the test fixture response from the device response within the test fixture. The device also had to have bias on several ports simultaneously. We had to establish a "reference plane" within the fixture, from which we can use the Vector Network Analyzer's Port Extension or Phase Offset to dial out the distance from our 1 port calibration reference plane to the point of short reference within the fixture. With this phase offset compensation we can then measure the device capacitance of the part...

AWR.TV Playing AWR's IMS2013

MicroApps Presentations

AWR Corporation has launched a fully redesigned AWR.TV portal directly from within its main website framework to enhance the viewing experience of AWR's hundreds of demos and tutorial videos. The new AWR.TV platform now supports multiple platforms for ready viewing on mobile devices such as iPads, iPhones, and Android handsets/tablets. Recently added additions to the AWR.TV platform include AWR's nine MicroApps presentations from IMS 2013.

Don't Lose Your Mobile Rig

"If the car is parked in a dark remote spot it is better to do the job where the car is. This is because auto burglary is a lesser crime than stealing the whole damn car." That remark was made by a 'former' thief who ostensibly gave up a life of crime after spending nearly two decades in the slammer for various infractions of the law. One of his specialties was breaking into cars to steal radios - AM, FM, CB, Ham, or whatever was available. Mr. X volunteered his insight for the benefit of QST readers who might want to take proactive steps to help minimize the chance of being a victim.

Thanks Again to Triad RF

Systems for Their Support

Your source for RF Front Ends, transceivers and amplifier systems that just plain work! Solutions for integrating high performance HPAs into sophisticated RF subsystems and systems without sacrificing efficiency and linearity. Please remember that DCH Systems merged with Triad RF Systems earlier this year.

Skyworks Front Ends Support

Broadcom 5G WiFi Platforms

Skyworks Solutions announced that its industry leading wireless connectivity FEMs are being leveraged by Broadcom for use in several of the company's 5G WiFi solutions, enabling some of the fastest download speeds available in access points, routers, DSL/cable gateways, PCs, smartphones and tablets.  Skyworks' complete 2.4 and 5 GHz 802.11a/g/n/ac solutions integrate the power amplifier, filter, power detector, T/R switch, diplexer and associated matching in an ultra-compact form factor, delivering all the essential functionality from the output of the SOC to the antenna.

Amateurs - Your Thoughts

May be Worth Money

During the Golden Age of Radio (admittedly a subjective term), electronics innovators were generally as likely to be hobbyists (amateurs) as they were to be professionals with college degrees. In fact, according to this open letter from Eugene F. McDonald, president of Zenith Radio Corporation, in 1939, his company recognized the fact that most of their best ideas came from amateur radio operators, and that their engineering staff was populated overwhelmingly with Hams. Accordingly, the letter was a solicitation to amateurs to submit their ideas to the company to give designers not just valuable technical information gleaned from real-world experimentation (aka the School of Hard Knocks) but also insight into what type of equipment the Ham world would like to have made available for sale. Wouldn't it be great to still see the foundational electronics brands...

Hams in Space

OK, I admit that the Hams in Space organizational patch caught my eye and that's why I'm writing about it. Their little ploy worked on me mainly because of its vintage design motif, but I'll be honest and admit there might have been another reason as well. "Hams In Space is one of the KD0HKD.COM Satellite Web Sites where you can learn how the Hams in Space Team can come to your Amateur Radio Club Meeting, Hamfest, or Event to provide a presentation on FM Amateur Radio Satellites!"

PMI Intros High Speed

SPST Switch for x-Band

PMI Model No. P1T-9D25G-90-T-SFF is a high speed, solid state, single pole single throw switch capable of switching within 20 ns. The frequency range is 9.25 GHz (±30 MHz) with >90 dB of isolation. 

Microsoft Visio 2003 Inside Out

Visio is still a mainstay for generating Office-compatible engineering block diagrams and schematics. Its ability to be programmed for automation makes it even more valuable to the code-writing guru. Microsoft Visio  2003 Inside Out covers all the ins and outs that you'll need to know to exploit its powers and to learn clever tricks for usage. "This supremely organized reference packs hundreds of timesaving solutions, troubleshooting tips, and workarounds all in concise, fast-answer format. It's all muscle and no fluff. Discover the best and fastest ways to perform everyday tasks, and challenge yourself to new levels of Visio mastery!"

Silvertone Radio Discovered

at Tony Packo's

If you happen to be a fan of the M*A*S*H television series from the 1970s, then undoubtedly you are familiar with Corporal Maxwell Q. Klinger's multiple mentions of his old neighborhood of Toledo, Ohio haunts - some manufactured and some real. His Toledo Mud Hens ball team, for instance, is real. Uncle Abdul (Klinger is of Lebanese-American descent) and his original wife Laverne Esposito (from the Hungarian side of Toledo) were obviously fictional; however, it was because of Laverne that Klinger was introduced to Tony Packo's Cafe - a real place. The Hungarian style hot dogs from Tony Packo's were tops according to Max. In fact, his mention on the television show launched Tony Packo's to stardom and to being a highly prized tourist destination. On Feb. 24, 1976, Jamie Farr (Klinger) put Tony Packo's on the map...

Engineers Troubleshoot

Problems Like Doctors

Diagnosis Sicknesses

Dave Palmer has a good piece on the Design News website titled "How to Be a 'Doctor of Engineering' Without Going to Grad School" about how, according to input from his son who is in medical school, the diagnosis technique being taught to aspiring doctors is similar to the troubleshooting technique used by (in Dave's case) mechanical engineers to get to the root of problems that are reported by customers. Doctors, at least during their training phase, use a four-step process termed "differential diagnosis." The doctor first notes symptoms and medical history, then considers possible causes for the malady, then prioritizes the list according to likelihood, and finally tests his conclusions by applying diagnosis and curative techniques. The parallel to electronic as well as mechanical troubleshooting...

Firefox Add-On Inserting

Popup into Web Pages

Internet advertising has hit a new low in the last few months. I have been noticing that every time I use the Firefox browser that ads are constantly popping up as the cursor is moved around the screen - even on the RF Cafe website -- which does not have and never has had popup ads. The screen capture below shows what I was seeing on my own website (RF Cafe)! I am NOT responsible for any popups that you might get, and neither are any of my advertisers. A Google search about the issue turned up many complaints about the same type of thing, primarily on Firefox. It turns out that an add-in, which must have been installed stealthily with an upgrade, was responsible. I don't visit questionable websites, so there is little chance it was picked up in that manner unless...

Fiber Optics Introductory

Tutorial by RP Photonics

RP Photonics Consulting GmbH has published a tutorial "that can serve as an introduction to fiber optics; i.e., for learning basic of fiber optics, but it also helps to improve the understanding for people who already have a substantial experience with optical fibers. The focus is on the physics of wave propagation and its technical consequences. We do not go into mathematical details, but rather try to create an intuitive understanding of the operation principles – often by demonstrating certain effects with numerical simulations. The simulation and design software RP Fiber Power of RP Photonics is an excellent tool for such purposes and has been extensively used for this tutorial." [App Note page link]

Notable Techie Quote

"In the mid-'90s, when downsizing was the dominant trend in business, Dilbert took off." - Scott Adams

Please Visit Anatech in

Appreciation of Support

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.

It's a Man's Job

Behind That Microphone

Of course if you listen to any of the old-time radio broadcasts on the Internet, they are recorded version of shows made long ago. However, back in the day those shows were first performed live in front of microphones and recorded in a broadcast studio. With a cast of two or three or even more, the actors would voice their lines with as much talent and effort as those performing for movies. The crew usually included a group of people responsible for creating background sound effects like horses running, car horns tooting, airplanes buzzing by, and dogs barking. All was done real-time with split-second timing required to pull it off and sound convincing. Radio audiences were unaware of all the work required as they sat intently listening to the Adventures of the Lone Ranger and The Shadow. Behind the scenes were dozens of engineers and technicians tending local radio broadcasting equipment and all-important telephone lines used for synchronizing...

Reflection/Transmission

Power Measurements

Obtaining accurate, reliable, and useful measurements of RF power in the forward (transmission) and reverse (reflection) directions requires careful selection of test devices and detection equipment. LadyBug Technologies has produced a white paper describing a method for performing reflection and transmission measurements using a power sensor and a directional coupler. It includes a discussion on coupler directivity and impedance match as a factor in measurement accuracy.

RF & microwave Crossword

Puzzle for 10/20/2013

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.

Polystyrene: Its Electrical and

Mechanical Characteristics

Polystyrene has been commonly used in capacitors since long before I came on the electronics scene. Its widespread use in electronic and electrical components was first adopted in Europe in the 1920s, and then later became popular in the U.S. where scientists improved its characteristics and lowered its cost to where it could be found just about anywhere current flowed. In its present form, polystyrene can be easily bent, cut, turned, polished, melted, drilled and tapped - truly a versatile material. This article provides a brief introduction to polystyrene.

Reduction of Distortion and

Noise with Inverse Feedback

Feedback circuits seem simple enough intuitively, at least for simple systems. It is easy, though, for someone not comfortable with algebraic manipulations to arrive at the wrong conclusion for how a given feedback constant figures into the calculation. Such was the case with an article published in the ARRL's QST magazine, when many readers wrote to the author accusing him of making an erroneous claim regarding using feedback to cancel out an unwanted harmonic in an amplifier. The criticism turned out being justified. Here is a statement of the error and an explanation of the proper approach which was printed a couple months later.

FCC Spectrum Dashboard

The FCC (Federal Communications Commission) has a very useful website set up for finding information about who owns spectrum licenses around the country, and what spectrum is available in your county. The Spectrum Dashboard has four primary methods for searching spectrum in the United States. You can use the dashboard to find out how spectrum is being used and by whom. There is an interactive allocation chart like the big wall charts that the magazines used to give away, only the nice thing about this one is that it never goes out of date. Of course the flip side is that if you wanted to research the historical band allocations you would need to look elsewhere.  From the main page you may perform the following searches. Be aware that the map does not display where the frequencies are licensed or being used...