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Homepage Archive March 2013


Wireless Crossword

March 31, 2013

Wireless Crossword Puzzle for March 31, 2013 (St. Patrick's Day) - RF CafeEvery 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.

Contra-Polar Energy

Contra-Polar Energy, April 1955 Popular Electronics - RF CafeContra-polar (negative) energy is a concept that has been investigated by many researchers beginning in the mid 19th century, when the nature of energy was beginning to be understood from a truly scientific perspective. Entire theories of universe and matter-antimatter creation have been published, reviewed and refined. This article from the April 1955 edition of Popular Electronics reports on then-current applications of contra-polar energy. At the time, most such work was performed in secret government laboratories and at test ranges that were closed to the public and results banned from publication, but since that time freedom-of-information-act requests have opened much contra-energy research information for public access.

Method for Selectively Creating

Fissile Mass Fragments

Alchemy? Scientists Discover Method for Selectively Creating Elements from Fissile Mass FragmentsThis is an interesting news item that made headlines recently. If its claims pan out, there could be a major shift in the electronics industry in terms of both product costs and product reliability. Scientists have evidently figured out a way to bombard heavy element isotopes with designer molecules to split the atoms in a specific manner, being able to produce atoms of gold, silver, titanium, etc., from atoms of uranium, lead, and other commonly available elements. Although the fissile fragments are at least for now considered an 'industrial' form (as opposed to for jewelry), it will greatly reduce the need for traditional minerals and elements so that prices should drop considerably. It also means engineers can be more generous with gold plating thicknesses on connector contacts, decorative trimmings, anti-corrosion coatings, etc. Materials engineers will be plenty busy figuring out ways to exploit (and profit from) the new technology.

Featured Book

Capacitors: Technology and Trends, by R. P. Deshpande. "Capacitor technology is changing rapidly in sync with emerging applications. Capacitors are increasingly being used for energy storage in UPS systems, in cellular phones, cameras and automobiles. In power utility grids, capacitors continue to enhance transmission capacity and reduce losses. Capacitors: Technology and Trends provides the reader not only current usage and trends for its application in the electrical and electronic sectors but also the basics of capacitor physics and the evolution of raw materials and manufacturing processes. The book aims to serve as a ready reference to students, researchers, manufacturers and users of capacitors."

Many Thanks to NIC for Their

Continued Support!

NIC is a leading manufacturer of custom RF & Microwave Filters, phase shifters, diplexers, TCXOs, discriminators, amplifiers, and many other RF / microwave assemblies. For over 20 years, they have been a trusted partner for military, commercial & space solutions. NIC headquarters is located in Overland Park, KS with additional sales and manufacturing operations in Washington, DC and India.

The Conical Monopole Antenna

The Conical Monopole Antenna, November 1966 QST - RF CafeAuthor Pappenfus presents in this article an alternative antenna for people operating at long wavelengths who do not particularly want or are prohibited from having a Yagi or similar structure. At 80 meters, for instance, a Yagi is only a little smaller than a football field - or so it seems. The sight of such a structure towering over a neighborhood house is to a Ham what the face of an ugly baby is to its mamma (something only a mother could love, per the old yarn). A conical monopole antenna may be a reasonable compromise. The conical monopole antenna is a base-fed vertical antenna having an omni-directional pattern in azimuth but with an elevation pattern that keeps most of the energy down close to the horizon, where it belongs for long-distance transmission.

The Tunnel Diode

The Tunnel Diode, September 1960, Popular Electronics - RFCafeLeo Esaki invented the tunnel diode in 1957 while working at Sony (Tokyo Tsushin Kogyo at the time). Tunnel diodes have a very narrow, heavily doped p–n junction only around 10 nm (100 Å) wide that exhibits a broken bandgap, where conduction band electrons and therefore on the n-side are approximately aligned with valence band holes on the p-side  facilitate the quantum mechanical tunneling process after which the diode is named. A negative differential resistance in part of their operating range makes them useful for high frequency oscillators. This article in a 1960 edition of Popular Electronics introduces the device's characteristics and potential uses.

Like a Hot Knife Through Butter

...with a New Twist

My son-in-law, Matt, showed me this video demonstrating the incredible thermal conduction property of graphene. A miracle material for seemingly every other realm of physics, thermo-conductive pyrolytic graphite (TCPG) conducts heat with twice the efficiency of diamond, and 6x the efficiency of copper and silver. Because of the extreme thermal conductivity, the heat from the guy's fingers is enough to slowly force the graphene sheet through the ice cube. In the future, the colloquial saying for expressing how easily a material is cut might change from "like a hot knife through butter" to "like a body-temperature graphene sheet through an ice cube."

Empower Demos NextGen

HPA Software Update Capability

Empower Demonstrates Next Generation HPA Software Update Capability - RF CafeA next generation, "size matters" 1 kW Power Amplifier from Empower RF Systems, already deployed at a customer site overseas, had its operating software and user interface successfully updated via a software patch that was downloaded from a secure web portal and installed with a USB drive inserted directly into the back panel of the amplifier. The upload process was streamlined for "ease of use" with a self extracting and self loading file that contained all updates, confirmed successful installation, and automatically reset the amplifier monitoring, control and performance parameters. No operator intervention or procedures were required other than downloading the software file onto a USB drive and inserting the drive into the USB port on the back of the unit.

A Japanese Hamfest

A Japanese Hamfest, January 1933, QST - RFCafeHams are a lot like most other dedicated hobbyists in that when it comes to enthusiasm in their chosen pastimes, there are no international barriers. Such is evident by this 1933 article in QST magazine reporting on a Hamfest in Japan. The world was a much larger place back then with propeller-driven airplanes making multiple stops on their way around the globe, transcontinental telephone was a service reserved mostly for the wealthy, and postal mail could (and often did) took weeks or months to be delivered from Iowa to Tokyo. The first television broadcasts were only a few years old so other than visiting far off lands, movies and photos were the only exposure the vast majority of people had to foreign cultures. Amateur radio operators of all social and economic standings were more cosmopolitan than most corporate managers in 1933.

Please Thank Skyworks for

Their Long-Time Support

Skyworks Solutions is an innovator of high performance analog semiconductors. Leveraging core technologies, Skyworks supports automotive, broadband, cellular infrastructure, energy management, GPS, industrial, medical, military, wireless networking, smartphone and tablet applications. The Company's portfolio includes amplifiers, attenuators, circulators, demodulators, detectors, diodes, directional couplers, front-end modules, hybrids, infrastructure RF subsystems, isolators, lighting and display solutions, mixers, modulators, optocouplers, phase shifters, PLLs, synthesizers, VCOs, power dividers & combiners, power management, receivers, and switches.

Will It Blend?

iPhone 5 vs. Galaxy S3

Will It Blend?iPhone 5 vs. Galaxy S3 - RF CafeBlendtec blender guy Tom is at it again, this time pitting an iPhone 5 side-by-side against a Galaxy S3 in yet another "Will It Blend?" adventure. This might be a first in Blendtec history - two blenders going at the same time! ...and to think you were alive at this moment in history to witness it personally (sort-of)! Slo-mo photography really adds to the excitement and anticipation. Early in the game the iPhone 5 is really taking a beating by the Blendtec Total Blender's razor sharp hardened steel blades, powered by one of the industry's most powerful motors. The tough case of the Galaxy S3 is still intact long after the iPhone 5 is reduced to fine black powder and a few bits of metal. Finally, the challenger subdues and meets a similar fate, brought low by the relentless pounding of the Blendtec. Hear Tom's hilarious description of the remains at the end of the video.

Electronics Crossword Puzzle

Electronics Crossword Puzzle from April 1967 QST - RF CafeQST occasionally ran a crossword puzzle with an electronics theme. This one appeared in the April 1967 edition. Enjoy!

Mechanical Meter Movements

Meters, September 1960, Popular Electronics - RF CafeMechanical meter movements have been around since the late 1800s. In 1882 Jacques-Arsène d'Arsonval and Marcel Deprez developed a meter movement with a stationary permanent magnet and a moving coil of wire which survives today as the dominant form. Lord Kelvin's galvanometer preceded d'Arsonval's by a decade or so, but it relied on the Earth's magnetic field and needed to be properly oriented to work. d'Arsonval's movement incorporated a permanent magnet instead to improve sensitivity and convenience. I'm not sure why d'Arsonval gets sole billing on the name - why not the Deprez movement? This article in Popular Electronics from 1960 is as relevant today as it was half a century ago.

<<<<<< NOTICE >>>>>>

I will be traveling for the next few days and will have limited access to e-mail and computer. Thank-you for your patience.

MECA Intros Low PIM

Terminations & Splitters

MECA Electronics Intros Low PIM Loads/Terminations & Unequal Splitters - RF CafeMicrowave

Components of
America Electronics is pleased to announce its Low PIM Loads / Terminations with industry leading -170 dBc (typical) Passive Intermodulation the  698 – 2700 MHz bandwidth. Ideal for IDAS & ODAS and In-Building, base station applications. Available in 20 W, 50 W, and 100 W versions. All models feature 7/16 DIN male & female or Type N male & female connectors. VSWR 1.10:1 (typical).

Hobnobbing with Harbaugh

Hobnobbing with Harbaugh, July 1970 Popular Electronics - RF CafeHere is a little electronics hobbyist humor in the form a comic series titled "Hobnobbing with Harbaugh," compliments of Popular Electronics. Citizens Band radio and dirty hippies were the topic of the day in the 1970, so that's what you see in a couple of these comics. The "Inventions Wanted" comic is my favorite, followed by "Mayday... Mayday!" You don't need to be an amateur radio operator to appreciate these comic strips.

Build a Field Strength Meter

Build a Field Strength Meter, September 1960, Popular Electronics - RFCafeThere is little incentive to build your own field strength meter these days when commercial instruments are readily available and relatively inexpensive. For instance, you can buy an MJF-801 FSM with a 100 kHz to 500 MHz bandwidth for just $30, brand new. More sophisticated, calibrated instruments are available for a lot more, but this basic unit is dirt cheap. However, if you want to read a little about the theory behind a field strength meter and see how one goes together, this article from Popular Electronics provides that opportunity.

Linx Intros R4 and F4 Series

GPS Modules

Linx Intros R4 and F4 Series GPS Modules Offering a Simple Solution for GPS Applications - RF CafeThe new R4 and F4 Series GPS modules from Linx make it cost effective to add GPS capability to new and existing applications through a simple serial interface. Designed with the SiRF-IV chipset, the R4 and F4 Series offer enhanced GPS solutions over older SiRF-III, with improved accuracy to 2.5 meters, 2X faster cold start times using CGEE 3 day satellite prediction, built-in jammer remover, and better reliability by tracking up to 48 satellites simultaneously. The R4 Series GPS module can be used as a drop-in replacement for the existing Linx SG Series GPS module, adding SiRF-IV technology to existing designs at a lower cost.

NuWaves Engineering Awarded

2 Unmanned Aircraft Contracts

NuWaves Engineering Awarded Two Contracts for Unmanned Aircraft - RF CafeNuWaves Engineering announced today that it has been awarded two contracts in support of Small Unmanned Aircraft Systems (UAS) programs related to communication data link range extension. The awards, both from U.S. Department of Defense prime contractors and related to small unmanned aircraft, include developmental work to customize NuWaves' field-proven NuPower™ miniature commercial-off-the-shelf (COTS) power amplifier (PA) modules.

AWR's Continues Its Graduate

Gift Initiative for a 4th Year

AWR Continues Its Popular Graduate Gift Initiative for a Fourth Consecutive Year - RF CafeAWR Corporation announces that it will continue to offer its popular Graduate Gift Initiative to graduating engineering students worldwide for a record fourth consecutive year. The AWR Graduate Gift Initiative program provides qualified electrical engineering graduates with free and fully functional one-year licenses of AWR software, inclusive of Microwave Office and Visual System Simulator software suites as well as AXIEM 3D planar EM simulation software.

Standardized Wiring Diagram

& Schematic Symbols

Wiring Diargram Schematic Symbols from April 1955 Popular Electronics - RF CafeElectronics symbols for schematics and wiring diagrams have remained amazingly consistent for the last hundred years, although obviously many new ones have been added. You can see from this set of standardized wiring diagram and schematic symbols from a 1955 edition of Popular Electronics what I mean.  Even symbols for newly introduced devices tend not to change. There are some variations such as whether or not to draw a circle around a transistor or how many lightning bolt lines to use with photon emitters and detectors, but that's about it. The digital world adopted IEEE Standard 91-1984 for logic and microprocessors, although you will still occasionally see variants in symbols, especially in early digital circuit schematics.

Many Thanks to Res-Net

Microwave for Their Support

For over 25 years Res-Net Microwave has manufactured precision RF & microwave attenuators, terminations, and other components, and now diode detectors for commercial, military, and space applications. Res-Net Microwave is a leader in the development and production of the metal films required for these types of RF/microwave attenuators, terminations, and resistors up to 2 kW.

EveryCircuit SPICE App

for Android

MuseMaze, EveryCircuit is possibly the best circuit design and simulation app on the Android market at the moment.Cabe Atwell, a contributing editor for Design News, comes up with a lot of good stuff in his blog that focuses on hardware and software design. This one highlights the EveryCircuit app for the Android market. "It is possibly the best circuit design and simulation app at the moment. It pulls in SPICE models of almost every component out there. Anything that can be done on a bench is in this app -- function generators, oscilloscopes. However, this app takes design to a whole new level of interactivity beyond that of even desktop apps. Watch how every component reacts in the circuit." Its price is a whopping $10.

April Fools in QST

April Fools Articles in 2013 QST - RF CafeQST often includes a couple gag articles in their April issues. A successful ruse contains enough information to appear legitimate while lacking detail that would normally be included in articles typical of the subject. I spotted three articles in the April 2013 edition that are potential candidates, but only one am I absolutely sort-of sure is a gag. All three suspect articles are technically feasible, but a lack of practicality is what tingles my spider senses.

Notable Quote

Notable Quote: "For God's sake, go down to reception and get rid of a lunatic who's down there..." - RF Cafe"For God's sake, go down to reception and get rid of a lunatic who's down there. He says he's got a machine for seeing by wireless! Watch him — he may have a razor on him." - Editor of the Daily Express (London), 1925, when TV inventor John Logie Baird came to demonstrate his technology

39 More Secrets Your

HR Person Won't Tell You

39 More Secrets Your HR Person Won’t Tell You - RF CafeAbout a year ago Reader's Digest posted a couple articles with confessions from Human Resources representatives and hiring managers. They revealed some of the practices that can help get you hired, and some that can keep you from being hired. Tips to keep you off the top of the layoff list are included as well. Here are a couple gems to whet your appetite.

* The No. 1 thing in job security is your relationship with your boss. Even if he says, "I'm sorry I really wanted to keep you, but they made me lay you off," that's almost never true. He probably made that decision.

* I know a lot more about you when you walk in the door than you realize. I'll search for you on the web and often use my own personal network to do a pre-interview reference check.

* You're right to be paranoid. The company is always watching you, and there's a record of everything you do: every phone call, every text, every tweet and instant message. At most companies, they save that data forever.

* If it's been a week or two and I tell you "I don't have an update yet," that often means there's a better candidate we're talking to, but we can't tell you that in case they decide not to take the job.”

AnalogRFic Design Services

Listing Added

AnalogRFic Design Services - RF CafeMr. Nandi Logan, of AnalogRFic Design Services company, invites you to visit his website to determine whether the expertise he and his expert partners have to offer can be of use to you. Per Nandi, "We are a group of analog & RF engineers providing design services & solutions. From the very first feasibility study to the final finished product, our consultants provide world class solutions in a timely manner. We provide designs & IP cores using the latest CMOS & BiCMOS technologies and on PCBs (FR4, Rogers, Duriod). On chip analog & RFIC designs – complete transceivers & ADCs. RF board designs from the antenna down to the baseband interface. Fast turn around MPWs & PCB prototypes. Expert witness services. Test & measurement services & automation programs."

Carl & Jerry:

Their Complete Adventures

Carl & Jerry: Their Complete Adventures is now available. "From 1954 through 1964, Popular Electronics published 119 adventures of Carl and Jerry, two teen boys with a passion for electronics and a knack for getting into and out of trouble with haywire lashups built in Jerry's basement. Better still, the boys explained how it all worked, and in doing so, launched countless young people into careers in science and technology. Now, for the first time ever, the full run of Carl and Jerry yarns by John T. Frye are available again, in five authorized anthologies that include the full text and all illustrations." I have posted a handful of the Carl & Jerry stories from scanned copies of the vintage Popular Electronics magazines. If you want old fashioned, clean adventures for yourself or your kids, this is it.

Vubiq Listing Added

Vubiq 60 GHz Tx/Rx Module - RF CafeVubiq has been added to the RF Cafe vendor listings. Located, Aliso Viejo, CA, Vubiq utilizes expertise in millimeter wave wireless to create disruptive applications for markets in which enormous bandwidths, low power consumption, and low cost are key considerations. Current products include turnkey Tx/Rx modules and attendant development systems in the globally unlicensed 60 GHz band, also 60 GHz wireless Ethernet links. If you've ever had a hankering to experiment in the mm-wave band, this is your chance. See the MVP article on Vubiq in the February 2013 edition of Microwave Journal.

Free Whitepapers

Free White Papers from RevResponse - RF CafeThe folks at Rev Response have a pretty big collection of whitepapers on a very wide range of subjects that are free for downloading. Well, not quite free - they do require you to sign in, but no $$$ is involved. I make a few pennies on each download, so you're helping to support RF Cafe if you participate. Here are a few of the newer ones that might interest you:

 - Migrating to BlackBerry 10:

 - Make Yourself Irreplaceable

 - Visio 2010 Quick Ref Card

 - How 3D Printing Works

 - Entrepreneur Equation

 - Before You Hire Employees

AWR Corp Needs a

Field Applications Engineer

AWR has an immediate opening for a highly motivated, self-directed Field Applications Engineer with experience using AWR's Microwave Office design suite, AXIEM 3D planar electromagnetic simulator or other high-frequency electronic design automation (EDA) tools. The successful candidate will conduct technical presentations and live software demonstrations to customers, including customized presentations as required. They will support technical evaluations / benchmarks and drive the process to deliver AWR solutions, as well as support strategic sales campaigns to generate product bookings at new and existing AWR accounts.

RF Engineering Crossword

March 24, 2013

RF Engineering Crossword Puzzle for March 24, 2013 (St. Patrick's Day) - RF CafeEvery 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.

March Magazine Articles

Microwaves & RF:

Optimize Time Gating in Spectrum Analysis, by Bob Nelson

Test & Measurement:

What's So Scary About Test Automation?, by Alex Henthorn-Iwane

Sherlock Ohms: Antenna

Tower 4 Has No Base Current

Sherlock Ohms: "Antenna Tower 4 Has No Base Current" - RF CafeSherlock Ohms is a regular feature of Design News that presents submissions from readers about troubleshooting challenges and how they were solved. This story titled "Antenna Tower 4 Has No Base Current" relates a broadcast station engineer's experience in troubleshooting a transmission cable problem between the radio station and its tower located ¼-mile away. Anyone not familiar with the type of lines run over those distances might be surprised at the culprit. Jim Flinn, friend from my USAF radar tech school days, spent many of his post-USAF years running his own commercial radio broadcast station maintenance company. The stories he has told and pictures he has shown me of some of those installations, which he says is more the rule than the exception, make you wonder how anyone stays on the air.

PMI Intros 30 MHz to 3 GHz

High Power Limiter

PMI Intros 30 MHz to 3 GHz High Power Limiter - RF CafeTPMI Model Number LM-30M3G-C3-1 is a high power limiter that operates from 30 MHz to 3.0 GHz. This limiter can handle input power levels up to 5 watts CW and provides a maximum leakage of +10 dBm. The insertion loss is 1.2 dB maximum with a maximum VSWR of 1.5:1. The recovery time is less than 1usec. This limiter is offered in a coaxial package. 

Anatech Electronics

March 2013 Newsletter

Anatech Electronics Newsletter for March 2013 - RF CafeAnatech Electronics has published its March 2013 newsletter. As always, it includes both company news and some tidbits about relevant industry events, regulations, and standards. Anatech Electronics' Sam Benzacar invites you to visit them in booth #2710 at the IMS 2013 trade show in Seattle, Washington.

Featured Book

Capacitors: Technology and Trends, by R. P. Deshpande. "Capacitor technology is changing rapidly in sync with emerging applications. Capacitors are increasingly being used for energy storage in UPS systems, in cellular phones, cameras and automobiles. In power utility grids, capacitors continue to enhance transmission capacity and reduce losses. Capacitors: Technology and Trends provides the reader not only current usage and trends for its application in the electrical and electronic sectors but also the basics of capacitor physics and the evolution of raw materials and manufacturing processes. The book aims to serve as a ready reference to students, researchers, manufacturers and users of capacitors."

Just in Case You Care...

USAF Forms and Certificates for Air Traffic Control Radar Repairman (Kirt Blattenberger) -  RF CafeWhile sorting through boxes of archived items recently, I ran across a pile of folders full of U.S. Air Force documents for base assignment, shot records, TDY deployment, training, performance reports, etc.. A lot of paperwork accrued in four short years. For out-processing (1982), I was issued a checklist that required going all over the base (Robins AFB, Georgia) to collect files, turn in issued gear, and sign multiple statements regarding why I was making the unwise decision to not re-enlist. Very few papers survived my purge; only the most significant remain. Here are a few of those documents, arranged in chronological order of issuance. If you, too, were in the USAF, many will look familiar.

Choosing Your TV Antenna

Choosing Your TV Antenna, December 1958 Popular Electronics - RFCafeWho cares about television antennas these days, you're probably asking? Many people might care soon. The December 2012 edition of the IEEE's Spectrum magazine had an article titled, "TV's Future: The Broadcast Empire Strikes Back." According to  author Lynn Claudy, the ATSC is working on a standard called Mobile DTV in the United States. MDVT enables broadcast stations to deliver programming to some cellphones, laptops, tablets and to moving television screens in cars, trains, and buses. Furthermore, a scheme to enable on-demand programming, user feedback (voting, polls, quizzes, games), and other advanced features is under investigation in research labs and field trials. Local businesses welcome a rebirth of regional over-the-air-broadcasts to provide pricing competition with dominant cable TV. So, although this article was originally written in 1958...

Donate Your Radio

Donate Your Radio - RF CafeThe Junior High School 22 in The Big Apple educates the kids in communications by teaching them Amatuer Radio - RF CafeThe Radio Club of Junior High School 22 (WB2JKJ) in New York is running a campaign to get people to donate unused Ham radio gear. Per the group's website: "Turn your excess Ham Radios and related items into a tax break for you and learning tool for kids. Donate your radio or related gear to an IRS approved 501 (c)(3) charity. Get the tax credit and help a worthy cause. Equipment picked up anywhere or shipping arranged. Radios you can write off - kids you can't." This applies to a school near you as well.

The Unitary Bundling Strap

The Unitary Bundling Strap - RF CafeU.S. patent number 3,102,311 was issued to a group of Thomas & Betts Corporation employees on September 3, 1963, for a "Unitary Bundling Strap,"...whose purpose is to secure "linear articles, arranged in bunched parallelism, with its tail end passed through its head and drawn taught thereon..." These devices were originally used primarily in electrical work, but have over the last half century evolved in use for everything from packaging to law enforcement. Can you guess what it is? Be careful if you are dyslexic and might misread the quoted part as "its head passing through its tail end" or you might conclude it describes a politician.

Brown, Lead Underpants


Brown, Lead-Underpant Moments - RF CafeI normally avoid a headline like that, but Rajan Bedi, author of this short story on proton radiation susceptibility testing, really seems to like the term since it is used repeatedly throughout. It is funny and conjures up a number of less-than-flattering images. We are accustomed to reading about testing with electromagnetic beams (cosmic rays, x-rays, microwaves, mm-waves, etc.) and electron beams (beta rays), but proton beams (alpha rays) are mostly an unfamiliar entity. Most of us can tell you how to create the former, but how about creating the latter, and why is there a need to test for susceptibility to them? How do you shield against alpha rays? Fast-moving protons, being large and heavy, can dislodge atoms from semiconductor lattices, potentially affecting a circuit. Proton beams are generated using nuclear accelerators. Spaceborne platforms are particularly vulnerable. The test setup described used thick, paraffin-impregnated blocks, which I always thought were used for blocking neutrons, not protons, so maybe that is the secondary radiation mentioned. If the proton source is anything other than a hydrogen atom (not deuterium or tritium), then it probably has a neutron or two attached to it. Brown, lead underpants, though, will stop the protons.

YL News and Views

YL News and Views, October 1966 QST - RF Cafe"YL" is the shorthand used by amateur radio operators when referring to female operators - Young Lady. Although still chosen as a hobby in larger numbers by men, ladies have long been avid participants in the art/science of Ham radio. The American Amateur Radio League's QST magazine devoted this "YL News and Views" column to their contributions many years ago - trendsetting in its day. This particular issue introduces Louise Ramsey Moreau as its new editor. Her interest in Ham radio was piqued when she realized "all the women heard on their receivers were not 'just wives,' but licensed operators." The rest, as said, is history.

KR Electronics Intro 2.5 MHz

Bandpass Filter

KR Electronics Intros 2.5 MHz Bandpass Filter - RF CafeR Electronics part number 3097 is a 2.5 MHz bandpass filter. The filter has a minimum 3 dB bandwidth of 1.5 MHz and has a sharp transition to the stopband attaining over 60 dB at 1 MHz and 4 MHz. Other center frequencies and bandwidths are available. Please consult the factory. Features 2.5 MHz Bandpass Filter 1.5 MHz min 3 dB Bandwidth Sharp Transition to the Stopband 60 dB min at 1 MHz & 4 MHz 50 Ω Source and Load PCB Mount Can also be supplied with connectors Data sheets are available at www.krfilters.com.

IEEE-USA Today's Engineer

IEEE-USA Today's Engineer, March 19, 2013 - RF CafeEach week the IEEE-USA sends out an e-mail that usually has at least one worthwhile - often more - story. Here are the ones that pass my test.

Nailing Your Performance Review Won't Guarantee You a Raise

The Reshoring Trend is Good for U.S. Engineers and America

Sci-Fi: Chicken or Egg?

Feds Plan to Increase Public Access to Research-Related Publications and Data

RFMD Announces Flexible

GaAs Sourcing Strategy

RF Micro Devices announced today a new Gallium Arsenide sourcing strategy intended to increase manufacturing flexibility, expand gross margin, and support aggressive growth. RFMD will phase out manufacturing in its Newton Aycliffe, UK-based GaAs pHEMT facility and transition most GaAs manufacturing to its GaAs HBT manufacturing facility in Greensboro, NC. RFMD will also partner with leading GaAs HBT foundries for additional capacity. The transition will occur over the next nine to 12 months to support existing mm-wave customer contracts. Once implemented, RFMD expects annual cost savings of approximately $20 million, or $5 million per quarter. 

VidaRF Intros Single Junction

Low-Cost Drop-In Isolators

VidaRF Intros Single Junction Low-Cost Drop-In Isolators - RF CafeVidaRF offers low cost Drop-In, 1”x1” Circulators & Isolators designed for various wireless and power amplifier applications. The robust design provides high performance and reliability, typical specs: VSWR 1.13 / Loss 0.25 dB / Isolation 23 dB, great IMD, and is magnetically shielded. Circuit tab can be straight or bent flush with base for surface mounting. To help ensure long term performance in a variety of applications, these packages are BeO-free and Neodymium-free. VidaRF also offers a wide selection of Isolators and Circulators designed to cover 80 MHz to 40 GHz. Configured to Coaxial, Drop-In, Surface Mount or Waveguide.

International Wireless

Symposium - April 14-18

IEEE MTT-S International Wireless Symposium - RF CafeThe IEEE MTT-S International Wireless Symposium (IWS) is being held this year from April 14 through 18 in Beijing, China. It is a major technical and commercial event. The IWS is organized by the IEEE. It is intended to provide bilateral technical and commercial access for the Chinese microwave and wireless community, which is rapidly growing, but presently without sufficient interaction with the global community. As the first of its kind, IWS will lead the way to similar events in other parts of the world with similarly developing technical communities. The IWS will be an annual event, rotating between locations within China that have significant microwave and wireless communities.

The Novice 90 Antenna

Do you know what a Fahnestock clip is? Chances are you would know one if you saw one, but you never knew what it was called. This article, requested by RF Cafe visitor Jan C., references a Fahnestock clip in the parts list for constructing an easily tunable long-wire antenna. The simple circuit uses just a handful of components for matching the high impedance antenna to a relatively low impedance coaxial cable feeder. A flashlight bulb and a few turns of wire act as an RF sniffer to tune for best match. A high quality ground is essential to the setup's operation so the author describes using copper sulphate crystals or rock salt to treat the ground rod vicinity for better conduction. It's a short article so go ahead and read it - if for no other reason than to see what a Fahnestock clip is.

Human Statue Punches Heckler

A Must-Watch Video

Human Statue Punches Heckler - RF CafeHow many of us would like to believe we have the guts to appropriately deal with this kind of pr**k? I love seeing guys like this get their comeuppance. The world is filled with his ilk who count on the public being too afraid to strike back.

Erie Resistor Corporation


Erie Resistor Corporation Advertisement, December 1958 Popular Electronics - RF CafeSince I live in Erie, Pennsylvania, an erstwhile very industrial, albeit small town, it is always nice to run across information on the area in my electronics magazines. There are still a few electronics businesses in Erie, but as with most of the manufacturing from long ago, high tech here is found mostly on the shelves of Best Buy and not on manufacturing lines. One notable exception is Bliley Electric Company, maker of crystal oscillators, who was established in Erie in 1930. Bliley still operates today in a building about two miles from my house. This advertisement from the December 1958 edition of Popular Electronics is by Erie Resistor Company. In doing a Google search, I found a brief history of the company on a UK website. According to the author, Erie Resistor opened a division in Yarmouth in 1932. Here is a reference to Erie Resistor Company...

Century Electronics Vacuum

Tube Tester Advertisement

Century Electronics Vacuum Tube Tester Advertisement, December 1958 Popular Electronics - RF CafeA few days ago I posted an old ad for Radio Shack and mentioned the tube testers that used to be in the stores for customers to use free of charge. Of course they also had a nice stock of replacement tubes for you to buy if needed. This advertisement for a typical tube tester by Century Electronics appeared in the December 1958 edition of Popular Electronics. According to the U.S. Bureau of Labor Statistics' inflation calculator, that $134.50 price in 1958 (the year I was born) would be equivalent to $1,080.50 in 2013 money - not too bad really especially since today such a contraption would be built in China.

The Vacuum-Tube Voltmeter

- A.C. and Ohmmeter Ranges

Test Instruments Part 5: he Vacuum-Tube Voltmeter - A.C. and Ohmmeter Ranges, May 1959 Popular Electronics - RF CafePopular Electronics ran a 5-part series on test equipment usage. This final article is on the use of a vacuum tube voltmeter (VTVM). Also in this edition is a construction article for RCA's VoltOhmyst VTVM kit, so the two compliment each other. Author Larry Klein discusses mainly the AC and ohmmeter 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 PCB Material

World for Support

PCB Material World is an independent distributor and market maker of PCB raw materials. We buy and sell PCB raw materials such as Copper Clad Laminates, Copper Foil, Drill Backer and Entry, among other items.

Notable Quote

Notable Quote: "My dynamite will sooner lead to peace Than a thousand world conventions" - RF Cafe"My dynamite will sooner lead to peace Than a thousand world conventions. As soon as men will find that in one instant Whole armies can be utterly destroyed, They surely will abide by golden peace." - Alfred B. Nobel, founder of the Nobel Prizes (those who can't do rhymes write in free verse)

RF Engineering Crossword

March 17, 2013

RF Engineering Crossword Puzzle for March 17, 2013 (St. Patrick's Day) - RF CafeEvery 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.

A V.H.F. Lazy-H Antenna

A VHF Lazy-H Antenna, December 1966 QST - RFCafeAs with most hobby and how-to magazines, QST has had a long-running monthly column featuring handy tips from readers and sometimes from the column editor's (currently Steve Sant Andrea) own experiences. It has taken various names over the years such as "Gimmicks and Gadgets" and now "Hints & Kinks." This installment from the December 1966 QST presents a short introduction to a VHF 'Lazy-H' antenna for mounting in the attic (outdoor restrictions were common even half a century ago). It is of simple construction using lamp cord in the configuration and element lengths given - still useful in 2013.

Hittite Releases March 2013

Selection Guide

Hittite Releases March 2013 Selection Guide - RF CafeHittite Microwave has released the March 2013 Selection Guide which summarizes over 1075 products including 20 new products. New for this publication is a Dual Low Pass Filter in the IF Baseband Processing Product line featuring an integrated ADC driver, programmable input impedance, and adjustable output common mode voltage from 0.9V to 3V with a 2 Vpp signal. The Selection Guide is organized by RF & Microwave, Analog & Mixed Signal, Clocks & Timing and LO Frequency Generation IC sections along with Modules and Instrumentation. The New & Expanded Product Line section includes new Amplifiers, Crosspoint Switch, Data Converters, Mixers, Optical Modulator Drivers, PLLs with Integrated VCOs, Transimpedance Amplifier and Transceivers.

Low-Loss Coaxial Cable

Low-Loss Coaxial Cable, December 1966 QST - RFCafeWhen it comes to low loss transmission media, it's hard to beat waveguide and open wire. Open wire can exhibit less a couple tenths of a decibel per hundred feet at low frequencies, but it is very susceptible to perturbations from nearby objects, wind and moisture. Waveguide exhibits a few tenths of a decibel per 100 feet at very high frequencies, but it is expensive and difficult to work with. In the middle is coaxial cable, which for a good quality product of appropriate size, you can get very low attenuation. As with most things, you get what you pay for in coax cable. I once used really expensive Andrew (now Commscope) Heliax coax cable on an S-band radar (2.8 GHz) system that had only a little more than 1 dB/100 ft, which was necessary from a receiver noise figure requirement rather than for transmitter power efficiency. This article from QST covers some of the basics of low loss cable.

PMI Intros 2-18 GHz

Low Noise Amplifier

PMI Intros 2-18 GHz Low Noise Amplifier - RF CafePMI Model No. PE2-25-218-20-12-SFF is a 2.0 to 18.0 GHz Low Noise Amplifier that provides greater than 25 dB of gain while maintaining a maximum gain flatness of ±1.5 dB maximum over the operating frequency. The noise figure is 4.5 dB typical and offers an OP1dB of +20 dBm minimum. The operating voltage is +12 to 15 VDC and the current draw is 300 mA maximum. This amplifier is supplied in a our PE2 package that measures 1.08" x 0.71" x 0.29". 

Please Thank Orbel for Helping

to Deliver This Website

Orbel is a precision solutions manufacturer of Photo Etched Components, Board Level Shielding, EMI/RFI Gasketing, Custom Metal Stampings, Fabric over Foam Gaskets and Plated Foils. Orbel's board level shielding products offer engineers the most flexibility for surface mount or thru-hole designs. Orbel specializes in custom single and dual junction Circulator and Isolator lead frames in beryllium copper and copper materials.

Featured Tech Book

The Google Resume: How to Prepare for a Career and Land a Job at Apple, Microsoft, Google, or any Top Tech Company, by Gayle Laakmann McDowell. "The Google Resume is the only book available on how to win a coveted spot at Google, Microsoft, Apple, or other top tech firms. Gayle Laakmann McDowell worked in Google Engineering for three years, where she served on the hiring committee and interviewed over 120 candidates. She interned for Microsoft and Apple, and interviewed with and received offers from ten tech firms. If you're a student, you'll learn what to study and how to prepare while in school, as well as what career paths to consider. If you're a job seeker, you'll get an edge on your competition by learning about hiring procedures and making yourself stand out from other candidates."

What Does Your Daily

Commute Cost You?

Cost of Commuting Infographic (Streamline Refinance) - RF CafeHow far do you commute each day for the privilege of doing your part to push back the frontiers of technical ignorance and to boldly go where no engineer - or technician - has gone before (split infinitive by Roddenberry, not me)? Do you know what the cost equates to you each year? This handy-dandy poster by the folks at Streamline Refinance lays out some gruesome numbers. Those with a weak stomach probably should pass on viewing this one. Here's a hint at what you will see: See that big $795 in the thumbnail image? That's the average cost per year for commuting -- per mile! Yessiree, if you live just 10 miles from work, you're losing nearly $8k per year, depending on you automobile type, on gas, tires, maintenance, devaluation, and loss of your personal time (which is valuable, after all). Back in the early 1990s I drove 45 miles each way to Comsat, which took about 65 minutes due to miserable traffic. That's 130 minutes round-trip, or 2 hours and 10 minutes (about the run time of an average movie) each day. Figuring two weeks vacation and 10 holidays, that leave 48 weeks x 5 days/week = 240 days per year of commuting. 240 days...

PMI Intros 30 MHz to 20 GHz

Low Noise Amplifier

PMI Intros 30 MHz to 20 GHz Low Noise Amplifier - RF CafePMI Model No. PUB-15-30M20G-20-LCA is a 30 MHz to 20.0 GHz Low Noise Amplifier which provides 15 dB of gain while maintaining a gain flatness of ±2.5 dB typically over the operating frequency. The noise figure is 3dB typical and offers a typical OP1dB of +20 dBm. The amplifier requires +12 to +15 VDC and the current draw is 225 mA typical. The unit is supplied with SMA(F) connectors in our standard PE2 housing.

KR Electronics Intros 124 MHz

Highpass Filter

KR Electronics Intros 124 MHz Highpass Filter - RF CafeKR Electronics part number 3094-1 is a 124 MHz highpass filter. The filter has a sharp transition to the stopband and attains over 70 dB by 110 MHz. Other bandwidths are available. Please consult the factory. Features 124 MHz highpass filter sharp transition to the stopband 70 dB min at 110 MHz high stopband attenuation 50 Ω source and load SMA connectors or surface mount.

Radio Shack Catalog

Advertisement c1962

Radio Shack Advertisement in the August 1962 Popular Electronics - RF CafeRadio Shack was opened in 1921 by brothers Theodore and Milton Deutschmann, then was bought by Tandy Corporation in 1962, reportedly for $300k. As well as being an outlet for hobbyists to buy common electronics parts, Radio Shack sold its own line of electronics like radios, calculators, and stereo systems under the brand name Realistic. A lot of people don't like Radio Shack the same way many don't like Walmart - usually for no good reason. I first started shopping at Radio Shack in the mid 1970s when I needed parts to build a homebrew stereo radio receiver from an article in Popular Electronics (if I remember correctly). I still like going in the store and looking around, occasionally actually buying something. Do you remember the Free Battery card they issued where you could get one free battery per month? How about the vacuum tube testers that were in the stores until the late 1970s? When our TV would crap out...

Finding Your Way in Space

Finding Your Way in Space, May 1958 Popular Electronics - RF CafeJust as today's generation of engineering students grew up with and are totally accustomed to and proficient at using computers, smartphones, positioning devices, CAE software, and various combinations of the aforementioned, so have the latest cadre of pilots grown up with GPS and electronic flight charts and planners in the cockpit. The difference is that whereas engineering students are not still required to learn to use a slide rule and a drafting table to earn an engineering degree, pilots are still required to learn to navigate using primitive (not meant derisively) instruments and ground-based navaids to earn a pilot's license. That's not a bad thing, though, because whereas if your graphing, 2500-function calculator quits working, the only thing at risk is your test score if you happen to be taking an exam. However, if your electronic navigation fails while in a limited visibility environment or in controlled airspace, you had better be able to do some seat-of-the-pants flying or you could be in deep doo-doo. This 1958 article from Popular Electronics presents the newfangled TACAN and Loran systems recently introduced (at the time) by the CAA, which is now the FAA. It was to dead reckoning navigation what the HP-35 calculator was to the slide rule.

Thanks Again to Fairview

Microwave for Support

Fairview Microwave, located in Fairview, Texas, is a "value added" distributor of RF, Microwave, Wireless & Fiber Optic passive coaxial components including coaxial cable assemblies , connectors, couplers, adapters, DC blocks, 90° hybrids, terminations, waveguide, and much more. Compliance screening is available.

FEKO 2013 Student Design

Competition Begins

FEKO 2013 Student Design Competition Begins - RF CafeNow in its 11th year, the FEKO Student Competition is open to all under-graduates and post-graduates who work on a supervised project in electromagnetic engineering and make use of FEKO. This annual competition is organised to give students an opportunity to showcase their work. There are some great prizes up for grabs – a state-of-the-art laptop computer or attendance to an industry related conference anywhere in the world!

everything RF Adds New

Online Company Directory

everything RF, the leading online product search tool for the RF & Microwave Industry, announced the release of an online directory dedicated to the RF & Microwave Industry. The directory lists companies in over 250 Categories/Sub Categories and enables users to narrow down on the list of companies by category, location, certification, or type of service provided. "We support over 250 categories and sub categories in the directory on everything RF and plan to add high quality companies to each category, making it a useful research tool for users who are looking for manufacturers and companies in a particular category," says Raghav Kapur, founder of everything RF. A basic listing in the directory is free, however this is subject to an approval process. If you would like to add your company to the RF Directory – Click Here.

Electronic Menu Quiz

Electronic Menu Quiz, August 1963 Popular Electronics - RF CafeThis electronic component quiz appeared in the August 1963 edition of Popular Electronics. It challenges you to match the common food-related term for a device with its picture. If you've been around electronics labs and/or read electronics hobbyist magazines for a while, chances are you have run across most of the terms.  A couple of the names I have to admit not being familiar, so they seem rather 'corny'... get it?

Vida RF Intros New N (Str & 90°)

and TNC Connector Lines

Vida RF Intros New N (Str & 90°) and TNC Connector Lines - RF CafeVidaRF has developed an all new line-up of Type N, Type N Right Angle, and TNC connectors that provide excellent performance from DC-18 GHz. The new designs from VidaRF can provide a significant cost savings when compared to traditional 18 GHz Type N and TNC connectors. Stainless steel passivated construction – can be built to accommodate any cable type.

EMI Troubleshooting Kit

EMI Troubleshooting Kit - RF CafeThere is a series of articles on the Test & Measurement website that are very much worth reading if your job or hobby involves hunting down RF/EMI leakage into or out of a PCB or enclosure. Author Kenneth Wyatt has an impressive bag of tricks you can use. One slick trick used by his colleague Doug Smith involves a literal bag with a few coins in it. Shaking said bag-o-coins generates EMI with edges in the 100 ps realm. I know from much experience about the electrical noise caused by metal-to-metal contact from the days of 27 and 72 MHz radio control systems in model airplanes. Throttle control arms on the carburetors used to be made of metal, and using a metal pushrod for connection would almost guarantee jittering servos from EMI interference. Meshing metal gears on early R/C helicopters was a nightmare. But I digress. Another nifty trick used by Mr. Wyatt is to use an igniter from a patio gas grill to generate wideband EMI. He has an easy-to-make spark gap tool as well. Take a few minutes to scan through some of the info; you'll be glad you did if for no other reason than the "well, huh!" factor.

AWR News Successes with

Asia Pacific Tech Universities

AWR Scores News Successes with Asia Pacific Technology Universities - RF CafeAWR Corporation today announces the addition of two new stories to its roster of university student and professor design successes using AWR software. These new stories include contributions from Okinawa National College of Technology in Japan and Macquarie University in Australia. Okinawa National College of Technology Dr. Koyu Chinen, professor at Okinawa National College of Technology, not only uses AWR design tools for his courses at ONCT, he also uses both Microwave Office® circuit design software and Visual System Simulator™ systems design software for his research projects, the most recent of which is the design of a large, complex climatology communication system using WiMAX, optical communications, and a climate satellite from the U.S. National Oceanographic and Atmospheric Administration.

Some QST Abbreviations

Used in Text and Drawings

Some QST Abbreviations Used in Text and Drawings - RF CafeGrammar and formatting standards have changed over time. As technology evolves and society devolves, things like abbreviations, use of capital letters, the 'verbization' of nouns (e.g., 'verbization'), interchanging of homophones (e.g., 'their' and 'there'), and the growingly popular offense of eliminating the space between a number and its associated unit (e.g., '914MHz' vs. '914 MHz') are becoming more prevalent. Look at nearly any press release or datasheet from a component manufacturer in the past year and you will notice the number-unit change (I correct many of the ones I post on RF Cafe). Some publishers (NPR) are particularly offensive at taking liberties (aka laziness) and others (New York Times) are stalwart standard bearers (good for them). I see many examples during my daily search for technical headlines. We have gotten accustomed to many changes, and some have been around so long that most people have never seen the former usage. Since I post a lot of articles from vintage editions of the ARRL's QST magazine...

Tales from the Cube

...an EDN Feature

Tales from the Cube: Rush-Project Troubleshooting Comes Down to the Wire - RF CafeThis episode, titled Rush-Project Troubleshooting Comes Down to the Wire, is included here not necessarily because the technical aspect of the story is exceptional, but because of the prank described in it. Wire-wrap board woes are all-too familiar to those of us who lived through them for prototyping in the 1970s and 1980s (before surface mount obsoleted DIPs). I personally built more than a hundred over the years. If you like waxing nostalgic over the era, read it anyway, but mainly read to learn a great gag to perpetrate upon a fellow engineer or technician. I rate it on par with rigging a length of Tyvek tubing stealthily into a chassis and having a cigarette smoker blow smoke through it from afar while someone is working on the circuit. Ah, those were the good old days!

Thanks to Empower RF

Systems for Their Support

 Empower RF Systems is a global leader in RF power amplifier solutions that are critical to defense, commercial, and industrial market applications. With their origins in the design of broadband and band-specific SSPAs, Empower continues to advance the science of RF power amplification to produce the toughest, most efficient and cost-effective solutions in the industry. Their priority is to design and deliver high quality, innovative products which solve customer systems and business requirements.

Notable Quote


Notable Quote: "To my mind, surveillance videos stand to be abused less if ordinary people routinely wear their own video-gathering equipment, so they can watch the watchers with a form of inverse surveillance" - RF Cafe"To my mind, surveillance videos stand to be abused less if ordinary people routinely wear their own video-gathering equipment, so they can watch the watchers with a form of inverse surveillance." – Steve Mann, electronic augmented eyewear pioneer, U. of Toronto Dept. of Electrical and Computer Engineering

More Problems - More

Questions and Answers

More Problems - More Questions and Answers, February 1967 QST-RFCafeHere is a good old fashion Q & A session on Ham radio topics... with the emphasis on 'old.' QST magazine published a couple of these columns in the 1960s, and this is the second in the series. I didn't read anything that wouldn't be applicable today, especially if you have some vintage gear. As with most such articles, there is something to be learned by just about anyone who deals with electronics, especially in the RF realm. One particularly interesting part is where the author, in response to a question about building and tuning your own radio, states, "Too many beginners are concerned about making 'Chinese Copies' of [manufactured] equipment described, even down to the same placement of nuts and bolts." Little did he know then that nearly every piece of equipment purchased new by Amateurs nowadays would actually be made in China and not in the USA.

"No, I Won't Sign Your NDA"

No, I Won't Sign Your NDA - RF CafeI'm a little conflicted and even a bit dubious about this article that appeared in the March 2013 edition of Inc magazine. The short piece by Chris Heivly, co-founder and managing director of the Triangle Startup Factory, insists that start-ups looking for investment capital should not expect initial talks to be predated upon the signing of a non-disclosure agreement (NDA). To do so, says the author, destroys 'deal flow' - the momentum he and his brethren investors need in order to quickly assess potential in many ideas being presented from many comers. In that case, the risk lies almost entirely with the investment seeker since he either lays his most valuable cards on the table in hopes that the investor is honest enough to not divulge his competitive forte, or forfeit an opportunity to develop his life's dream. What if your exposed plan that does not pass muster with the investor happens to provide just the tip needed for one of the investor's active clients either currently or in the future? Even an honest player can inadvertently tip off your hand. It's a tough call.

Wireless Crossword Puzzle

for March 10, 2013

Engineering Crossword Puzzle for March 10, 2013 - RF CafeEvery 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.

Test Equipment Product and

Application Specialist Needed

Technical Manager Needed by Advanced Test Equipment Rentals, March 9, 2013 - RF CafeAdvanced Test Equipment Rentals has a job opening for a Test Equipment Product and Application Specialist. The successful candidate will have previous marketing experience in product management in electronic test equipment or related field, marketing or sales experience with electronic test equipment manufacturers, basic understanding of the equipment and applications used by engineering departments in the design and test of RF, Microwave, EMC, AC and DC Power, Telecom and general purpose test equipment. He/she will identify and recommend products and related peripherals and accessories to add to our rental inventory, recommendations based on analysis and understanding of market needs, trends, competitive intelligence, and ROI. Also forecast revenues in various equipment categories and gather market data ensuring our rental inventory levels are in line with market demand.

Technical Manager Wanted

Technical Manager Needed by Advanced Test Equipment Rentals, March 9, 2013 - RF CafeAdvanced Test Equipment Rentals has a job opening for a Technical Manager. The successful candidate will have minimum of 5 years' experience in a civilian cal lab, must be familiar with a wide variety of test & measurement equipment, must be computer literate in Mudcats, and must have a good attitude and be able to work under stress in a fast paced environment. He/she will write UM for Cal Lab, write Cal Procedures & create templates, and train technicians on Calibration.

Please Thank Dow-Key

Microwave for Their Support

Dow-Key Microwave Corporation is the world's largest manufacturer of solid state, electro-mechanical RF and optical switches, along with programmable attenuators and delay lines. They are AS9100/ISO-9001 certified and committed to providing unparalleled customer service, competitive pricing, on-time delivery and switch products that are distinguished by quality and reliability.

IPP Intros Dual Directional Cplr

w/Separate Coupled Ports

IPP Intros SMD Dual Directional Coupler with Separate Coupled Ports - RF CafeInnovative Power Products introduces their Model IPP-8042, a 100 W, 35 dB, Surface Mount Dual Directional Coupler that operates from 225–2500 MHz. The IPP-8042 is a unique broadband design which provides separate coupled ports for both forward and reflected signals with internal Terminations. This coupler is produced in a Surface Mount package size of 0 1.00 x 1.00 inches. Insertion Loss is less than 0.30 dB, main line VSWR is less than 1.25:1, coupled flatness is ± 1.0 dB and directivity is greater than 18 dB.

Featured Book

MIMO Communication for Cellular Networks (Information Technology: Transmission, Processing and Storage), by Howard Huang, Constantinos Papadias, and Sivarama Venkatesan. "As the theoretical foundations of multiple-antenna techniques evolve and as these multiple-input multiple-output (MIMO) techniques become essential for providing high data rates in wireless systems, there is a growing need to understand the performance limits of MIMO in practical networks. To address this need, MIMO Communication for Cellular Networks presents a systematic description of MIMO technology classes and a framework for MIMO system design that takes into account the essential physical-layer features of practical cellular networks. In contrast to works that focus on the theoretical performance of abstract MIMO channels, MIMO Communication for Cellular Networks emphasizes the practical performance of realistic MIMO systems."

WWV Moves to Colorado

WWV Moves to Colorado, January 1967 QST - RFCafeThis is the first of a two-part series on the move of the WWV transmitter stations operated by the National Bureau of Standards (now called National Institute of Standards and Technology) from Greenbelt, Maryland, to Boulder, Colorado. WWV Part II appeared in the February 1967 edition of the ARRL's QST magazine. WWV began transmitting time / frequency standards in 1920 in order to provide a means for remote stations and laboratories to calibrate local standards that would prevent transmitting stations from interfering with each other. Although most people don't realize it, the 60 kHz signal that their 'atomic' clocks and watches use to self-adjust time emanates from the WWVB antenna in Boulder. This first installment of the article discusses the history and rationale for relocating the WWV facility to a new location. The second part gets into the technical aspects of the WWV facility's equipment and operation. As usual, I am amazed at the pioneers who conceived of, designed, and implemented these kinds of operations.

Frozen Android Phones

Give up Data Secrets

Frozen Android Phones Give up Data Secrets - RF CafeA lot of people sit around thinking about ways to compromise digital data, but who says to himself, "I think I'll try putting a cellphone in the freezer for a while to see if I can get it to give up its encrypted data?" Well, a group of geniuses (meant as a compliment) at Germany's Erlangen's Friedrich-Alexander University (FAU) just did. Using a program called Forensic Recovery Of Scrambled Telephones (FROST), the team discovered that by lowering the temperature of the semiconductors and performing a manipulation of the battery and button presses, the phone could be made to start up in its 'fastboot' mode to access Recovery Mode. Next, find the FDE key file and crack the 4-digit PIN using FROST. It's that easy. This gives a whole new meaning to a 'cold' boot.

Technical Product Manager

Wanted by Pasternack

Technical Product Manager Wanted by Pasternack Enterprises, March 6, 2013 - RF CafePasternack Enterprises is a B2B Direct Marketer to the RF and Microwave industry niche. The company makes available the broadest selection of engineering grade components and assemblies available for same day shipment to a global customer base. We are currently looking for an experienced Product Manager to provide technical guidance and support to customers, suppliers, production, purchasing and sales and marketing. The successful candidate will demonstrate depth of knowledge and experience with a wide range of RF components and assemblies and understand the applications and technical market drivers in the RF industry.

Impact of Ultralow Phase Noise

Oscillators on Systems

Impact of ultralow phase noise oscillators on system performance - RF CafeCrystek Corporation's Ramón M. Cerda has published a new white paper titled Impact of Ultralow Phase Noise Oscillators on System Performance. "There is an abundance of information available regarding system performance and phase noise, but sometimes it is difficult to 'ferret out' the interesting material. This week we bring you a different perspective on this all important topic... This paper gives a new look at the relationship between phase noise in the frequency domain, and jitter in the time domain."

Empower RF Intros 5U Rack-

Mount 1 kW Power Amps

Empower RF Systems 1 kW PA Systems in 5U Chassis Available for Immediate Delivery - RF CafeEmpower RF Systems is delivering units from its “Size Matters” 1 kW Power Amplifier portfolio to Richardson RFPD as an integral part of a test & measurement promotion that Richardson RFPD is sponsoring on its website. Empower's 1 kW HPAs in a 5U chassis are unique in the industry - the collaboration between Empower and Richardson RFPD to have these units (and complimentary cables, coupler, and adaptors) readily available for customers is unique as well. Currently available in the frequency ranges of 20-500 MHz, 500-1000 MHz, and 20-1000 MHz.

The Whys and Wherefores

of Watts

The Whys and Wherefores of Watts, January 1957 Popular Electronics - RF CafeMost of the visitors to RF Cafe are either engineers, technicians, or hobbyists who deal with watts in terms of electrical power. This article from the January 1957 edition of Popular Science deals primarily with watts in terms of acoustic power, but it also addresses how obtaining acoustic watts relates to electrical watts. Audiophiles will appreciate the table of speaker watts needed based on your room volume as well as rules of thumb for selecting the amplifier power required to deliver that sound effectively.

Skyworks Supports In-Car

Infotainment Systems

Skyworks Supports Automotive Infotainment Systems for Global Car Manufacturers - RF CafeSkyworks Solutions announced that its industry-leading Silicon-on-insulator (SOI) switching technology is now being utilized by European, Japanese, Korean and North American car manufacturers for advanced infotainment systems. Specifically, Skyworks' solid state technology is enabling seamless low noise and broadband switching between audio, Blu-ray/DVD, navigation, cell phone and vehicle security display inputs as well as a variety of other high bandwidth media sources in automobiles.

USAF Radar Photos at

Aviano Air Base, circa 1970

USAF AN/MPN-14 Radar System at Aviano AB, Italy c1970 - RF CafeFellow USAF radar tech Greg Bucchieri just sent me some pictures he took while at Aviano Air Base in Italy. One is of the AN/MPN-14 mobile radar system that he helped bring back from Vietnam. The other is a photo of the radar clutter fence erected at Aviano AB. An incredible view of the Alps in the background which alone makes viewing the picture worthwhile, even if radars do nothing for you.

AWR Student Competitions

in China Jumpstarts Careers

AWR Sponsorship of Student Design Competitions in China Jumpstarts Engineering Careers - RF CafeAWR Corporation, the innovation leader in high-frequency EDA software, today announced the sponsorship of two major student design competitions in China as part of the company's continuing focus on working with universities worldwide to empower students with RF/microwave software tool experience and jumpstart their engineering careers. AWR's objective in sponsoring these competitions is to encourage students in China to become involved in the dynamic profession of microwave and RF engineering and to apply their knowledge to practical designs using the highly efficient AWR design methodology.

Please Visit DYNE-TECH in

Appreciation of Their Support!

DYNE-TECH manufactures RF & microwave components and subsystems for military and commercial telecommunications systems. Their products benefit from application of experience gained on government and university research programs. DYNE-TECH has built a reputation as a reliable supplier of stable, quality components. Specializing in large volume production of RF filters, terminations, couplers, connectors & adapters, dividers & combiners, and lightning arresters.

1/f Noise - the Flickering Candle

1/f Noise - the Flickering Candle - RF CafeHere is a good short tutorial on 1/f noise from the EDN website. Says TI's Bruce Trump, in part, "It's also called flicker noise, like a flickering candle. Seen on an oscilloscope with a slow sweep it has a wandering baseline (figure 1) because the high frequency noise rides on larger low frequency content. Pink noise, another metaphoric name, also suggests the stronger low frequency component. Flicker noise seems ever present in physical systems and life science. Weather/climate patterns, for example, have a 1/f component..."

March IEEE Spectrum

1/16-inch Thick

March 2013 IEEE Spectrum only 1/16" thick! - RF CafeAm I the only one who thinks the trade magazines have been getting thinner? The March 2013 edition of IEEE's spectrum magazine arrived today and it is only 1/16 inch British Library's Newspaper Storage Building computer racks (Spectrum) - RF Cafe(1.6 mm) thick! A lot of magazines are migrating toward online-only publication in order to save money. Online isn't free be any means, especially when you have to archive millions of pages of text and accompanying images. The thumbnail above shows the British Library's new Newspaper Storage Building that will archive every available issue of the newspaper dating back into the 1800s. A robot will retrieve hard copies to the requester. The room will be airtight and climatically controlled to preserve the papers and prevent fires. By contrast, a cluster of hard drives about the volume of my desk could probably hold the equivalent in digitized format.

For Safety's Sake

For Safety's Sake, December 1966 QST-RFCafeThis is a story with a lesson learned by the author and thousands of others ever since electric power appliances and tools first became available. Fortunately, his Ham buddy was not permanently harmed, but even today with all the effort put into educating the public, people continue to use ungrounded (2-wire type, or with the ground prong removed) extension cords in conjunction with 3-wire power cords on tools and end up electrocuting themselves (or somebody else). I've told the story before about a friend of mine from high school who shortly after graduation was making a piece of furniture in a garage that had a damp dirt floor, and was electrocuted to death by the metal-framed circular saw that had no ground connected. Nowadays we often have power provided by a GFCI receptacle when working outdoors or under a house, but I sure would not rely on it performing properly in lieu of taking prudent safety precautions. Hopefully you don't, either.

Inc Survey: What Makes

EEmployees Unhappy

Inc: What Makes Employees Unhappy - RF CafeInc magazine recently conducted a poll about what employees need from their employers in order to be happy and stick with their jobs. Responses depended heavily on gender (that thing we're told has no distinction in the workplace) and age (which is OK to discriminate against). Here are some findings. Overall, 69% like their co-workers and 54% like their bosses. 33% hate the stress level and 28% think they're not being paid enough. 18% expect free beverages, 17% feel owed a personal smartphone, and 8% want free massages. 45% of Men want more money and 39% want a promotion, while 51% of Women want reduced hours and 50% want flexible hours (uh-oh, that doesn't fit the media template).

Congrats to Walt G. for Being

the February 2013 Book Winner

LCP for Microwave Packages and Modules - RF Cafe Book GiveawayWalt G., of Delmar, DE, is the winner of the February 2013 Book Drawing! LCP for Microwave Packages and Modules is a "Comprehensive overview of electrical design using Liquid Crystal Polymer (LCP), giving you everything you need to know to get up-to-speed on the subject. This text describes successful design and development techniques for high-performance microwave and millimeter-wave packages and modules in an organic platform. These were specifically developed to make the most of LCP's inert, hermetic, low-cost, high-frequency (DC to 110+ GHz) properties. . Graciously provided by Cambridge University Press

Notable Quote


Notable Quote: "I am tired of all this thing called science"" - RF Cafe"I am tired of all this thing called science... We have spent millions in that sort of thing for the last few years, and it is time it should be stopped." - U.S. Senator Simon Cameron (1861), re funding for the Smithsonian Institution.

Velveeta Cheese Honors

the "Ham in the Basement"

Have you seen this? "You know that guy that's got a Ham Radio in his basement?? He can can talk to China, Mongolia, and all the Koreas, and he eats Velveeta Shells & Cheese. So who are you calling 'Amateur?'" Liquid Gold. Eat like that guy you know." Be sure to pick up a pack of Velveeta Shells & Cheese on your next shopping trip.

Please Welcome

Windfreak Technologies!

Windfreak TechnologiesWindfreak Technologies designs, manufactures, tests and sells high value radio frequency products such as RF signal generators / synthesizers, RF power detectors, RF mixers, upconverters and downconverters. SynthNV is a  37.5 MHz - 4.4 GHz USB powered and programmed RF Signal Generator / RF Power Detector. MixNV is a 30 MHz - 5 GHz USB powered and programmed RF Mixer / Signal Generator. SynthUSB is a 137.5 MHz - 4.4 GHz USB powered and programmed RF Signal Generator

Engineering Crossword Puzzle

for March 3, 2013

Engineering Crossword Puzzle for March 3, 2013 - RF CafeEvery 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.

PMI Intros 30 MHz to 20 GHz

Low Noise Amplifier

PMI Intros 30 MHz to 20 GHz Low Noise Amplifier - RF CafePMI Model No. PUB-15-30M20G-20-LCA is a 30 MHz to 20.0 GHz Low Noise Amplifier which provides 15 dB of gain while maintaining a gain flatness of ±2.5 dB typically over the operating frequency. The noise figure is 3dB typical and offers a typical OP1dB of +20 dBm. The amplifier requires +12 to +15 VDC and the current draw is 22 5mA typical. The unit is supplied with SMA(F) connectors in our standard PE2 housing. 

KR Electronics Intros 40 MHz

Bi-Directional Notch Filter

KR Electronics Intros 40 MHz Bi-Directional Absorptive Notch Filter - RF CafeKR Electronics part number 3092 is a 40 MHz absorptive notch filter. The filter has a typical 3 dB bandwidth of 16.5 MHz and has a maintains 50 dB rejection from 39 MHz to 41 MHz. The filter is absorptive in both the forward and reverse direction providing excellent match even at the notch frequency. The filter is supplied in a surface mount package measuring 1.0” x 0.5 x 0.3”. Other notch frequencies and bandwidths are available.

Quality Manager Needed

by Semtech Corp

Quality Manager wanted by Semtech, March 1, 2013 - RF CafeSemtech, a leading supplier of high-quality analog and mixed-signal semiconductor products for smartphones, notebook computers, WLAN modems, AMR, satellite communication, cellular infrastructure, and more, has an opening for a Quality Manager. The candidate must make significant contributions to preventing quality issues and to making continuous improvements. He/she also defines and specifies the implementation of standards, methods, and procedures for inspecting, testing, and evaluating the precision, accuracy, and reliability of company products.

Featured Book

Essentials of RF and Microwave Grounding, by Eric Holzman. Grounding is a widespread and serious problem in microwave and RF engineering and, up until now, there hasn't been a practical, authoritative resource dedicated to the topic. This first-of-its-kind volume offers professionals a comprehensive understanding of the proper grounding techniques to use when working on varied microwave circuit and antenna design projects. Practitioners learn what problems can occur when grounding design is inadequate, and how to avoid them. The book covers a wide range of critical topics, from the fundamentals of low frequency circuit theory and the differences between DC and RF short circuits...to grounding in active microwave component design and grounding issues related to antennas.

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024


    Kirt Blattenberger,


RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

Copyright  1996 - 2026

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

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