Homepage Archive #4

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page. About RF Cafe.

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Sherlock Ohms: The Shocking

Truth About FETs

Sherlock Ohms is a regular feature of Design News that presents submissions from readers about troubleshooting challenges and how they were solved. This one is titled "The Shocking Truth About FETs."

September 11, 11 Years Later

Have You Forgotten?

No sane person wants to dwell on tragic events solely as an opportunity to wallow in endless misery. Rather, in scenarios like the September 11, 2001 attacks on America's homeland, lessons should be learned and systems put in place to help mitigate the probability of similar misfortunes ever befalling the United States again. Then we move on. Is that what has happened? Have we learned a lesson and adopted a new mindset where sucker-punched citizenry now eternally guards against the forces that threw the fatal blow to over 3,000 souls? Sadly, it seems not. In an age of short attention spans, the country 's collective memory has all but been erased. A line from the song Have You Forgotten? goes like this, "They took all the footage off my TV, said it's too disturbing for you and me. It'll just breed anger, that's what the experts say. If it was up to me, I'd show it everyday." That was wayyyyyyy back in 2003, a mere two years after the attacks. Eleven years have passed now and the amnesia problem is infinitely worse. A constant pounding by the mainstream media day in and day out admonishing - even threatening - us to not remember exactly who the perpetrators were or where they came from has resulted in egregious actions by our government to the opposite extreme. Not only are...

Table of Contents' for

Vintage QST Issues Posted

A couple years ago I began posting selected articles from QST magazines from the World War II era. There are 30 articles thus far, and four full-page advertisements of companies like RCA and Simpson Electric. More will be added as time permits. Let me know if you see something in the TOC that you would like to have posted.

Microwave Engineering Theme

Crossword for 9/9/2012

For the sake of avid cruciverbalists, each week I create a new crossword puzzle that has a theme related to engineering, mathematics, chemistry, physics, and other technical words. You will never be asked the name of a movie star unless he/she was involved in a technical endeavor (e.g., Hedy Lamar).

Thanks to JQL Electronics

for Long-Time Support!

Microwave ferrite isolators & circulators, directional couplers, power divider/combiners, ceramic filters, and power transformers. Surface mount, microstrip, waveguide, adapters. Power supplies, transformers.

More Smith Chart Art

If you have never seen it, I began collecting examples of Smith Chart art a few years ago. While reading through the website of Prof. Aziz Inan of the U. of Portland, I discovered that he had his students create some Smith Chart art on the August 29th, 25th anniversary of Phillip Smith's death. It might not be as alluring as Pamela Anderson's Smith Chart T-shirt, but if a coloring exercise helps get students familiar with Mr. Smith's wonderful chart, then so be it.

A Numerical Investigation of

David Packard's Birth Date

U. of Portland electrical engineering professor Aziz S. Inan, Ph.D., just called to let me know about his "100th-Birthday Brainteaser Gift for David Packard" (September 7 is Mr. Packard's birthday). Prof. Inan likes to perform numerical investigations on dates of notable people and events. Not to be confused with numerology, his treatises reveal interesting mathematical relationships of the numbers associated with his subjects. It takes a lot of work to put these papers together. Nerd hobbies confound non-nerds, but the rest of us appreciate the effort.

PMI Intros 20 W, 14.4-15.4 GHz,

SM, SPDT Solid State Switch

PMI Model No. P2T-14D415D4-15-SMT-20W is a driverless, 20 Watt, SP2T Solid-State Switch that is supplied in a compact surface mount package. Operates from 14.4 to 15.4 GHz with insertion loss of 1.2 dB max at +25°C. Tx/Rx isolation is better than 10 dB and this switch can handle input power levels up to 20 W.

Free White Papers

Here are a few of the many free papers available from TradePub.

• Invaluable: Making Yourself Irreplaceable

• 2012 Small Business Toolkit

• Ultracapacitor Applications in the Power Electronic World

• Testing the Reliability and Safety of Photovoltaic Modules: Failure Rates and Temperature Effects

• Photoshop CS6 Unlocked: 101 Tips, Tricks, & Techniques

Thanks to Res-Net Microwave

for Supporting RF Cafe

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, for commercial, military, and space applications.

Early Infrared

It was 1958, over the Taiwan Strait, when the first Sidewinder air-to-air missile flew up the tailpipe of a MIG-17 Fresco after being launched by an F-104 Starfighter. The age of offensive infrared (IR) warfare had begun. It is amazing that the detection and guidance system for the Sidewinder was built largely from discrete components, without the advantage of large scale integration. IR night vision devices were actually used by the military as early as WWII with the renown Snooperscope (handheld) and the Sniperscope (mounted to a carbine rifle). Both required an infrared light source to illuminate the target. Today's night vision goggles and scopes are sensitive enough to be totally passive. This "Infrared" article from the February 1961 Popular Electronics talks about early developments in infrared technology. Corny-looking prototypes of IR wireless phones are shown, but...

Thanks for Cobham Antenna

Systems' Long-Time Support

Please visit Cobham Antenna Systems (formerly European Antennas) in appreciation of their helping to deliver RF Cafe. Cobham provides high gain, printed circuit arrays, ultra wide-band spirals, multi-octave bicones and collinear omnidirectional antennas from 100 MHz and 40 GHz. Custom designs. WLAN, RFID, WiMAX, TETRA, and telemetry.

September RFTI Articles

Material Choices and Tradeoffs for Printed Circuit Board Antennas (p.12), by J. Coonrod

A Review of Smart Grid, Smart Metering Technology and its Uses (p.22), by D. Tomanek and J. Alrawi

RF Fundamentals – Low Noise Design Technique (p.30), by

Gary Breed

Where the Jobs Are: 2012

New electrical and computer engineers stepping out into the real world this year might not get the multiple job offers and off-the-charts starting pay of the pre-crash days, but they can rest assured that their skills will be put to good use. Hiring is up by 10 percent over last year, and pay has increased slightly for electrical and computer engineers of the class of 2012.

Hittite's 2W & 5W Power

Amplifiers Cover 9 to 14 GHz

Hittite Microwave has launched 3 new four stage GaAs pHEMT MMIC 2 watt medium power amplifiers with temperature compensated on chip power detectors which operate between 9 and 14 GHz. Ideal for microwave radio, military and space, SATCOM and test & measurement applications.

Notable Quote

"Scientists like to say that a discovery's significance can be measured by how many prior scientific papers it renders obsolete." - Timothy Ferris, May 2012 Smithsonian magazine.

Please Visit Noisecom in

Appreciation of Their Support

Off-the-shelf & custom designed noise testing solutions. Noise standards, BER testers, analog & digital noise sources, noise diodes, calibrated noise source, HD radio test set. Repair & calibration services.

Free Webinar

Power Amplifier Design with X-Parameters, by Agilent & MWJ, Thursday, September 6, 1:00 PM ET

Are You Smarter Than a Junior

Year Engineering Student?

Smithsonian magazine had a one-page feature promoting the soon-to-be-opened Manhattan Museum of Mathematics, and included a URL for a 10 question test of your mathematics skills ranging from Algebra I to Calculus. Any engineer should whip through it quickly... unless maybe you have been out of college for a few decades. In the spirit of Jeff Foxworthy's Are You Smarter Than a 5th Grader?, I challenge you here. My score? I got 10/10 but only after finally figuring out the interior angle requested for the pentagon is not the total but just for one angle.

Solid State

In 1967 when this article appeared in Popular Electronics, the use of integrated circuits in consumer electronics was still relatively new. RCA, GE, Westinghouse, and Philco had just released their first TVs and radios with IC front ends, and Heathkit even had a build-it-yourself model. The military was using them (ICs) in proximity fuse designs. The new technology was really cooking. ESD issues were discovered and needed to be dealt with as gate sizes shrunk and the vulnerability to arcing became a problem. A photo is shown where NASA developed a method for mitigating the potential damage by looping a spring-loaded wire around the leads of MOS-based ICs during handling...

AWR Design Forum (ADF) 2012

Tours Europe This Autumn

France and UK Venues Conjoin as National Instruments/AWR “RF and Microwave Design and Test Forum.”

Congrats to Craig P.

August Book Winner!

Craig P., of Cambridge, MA, is the August 2012 book drawing winner! Craig selected Modern Communications Jamming Principles and Techniques (Graciously provided by Artech House). 80 books given away to date.

Thanks to Boonton

for Continued Support

Test equipment for measuring the power of RF and microwave systems used in both military and commercial sectors. RF voltmeters, peak & CW power meters, spectrum & modulation analyzers, capacitance meters.

Please Welcome Pasternack

as Our Newest Sponsor!

Global supplier of RF, microwave, wireless and fiber optic components and assemblies supported by international distributors who service customers in more than 30 countries worldwide.

The Global Brain Trade

The September 2012 edition of IEEE's Spectrum magazine has an interesting chart on the last page that shows the percentage of researchers that immigrate/emigrate to/from 16 different countries versus how many emigrate from the them. The chart bars represent percentages, not absolute numbers. Switzerland has the highest number of researchers immigrating to it (~60%) while about 35% emigrate from it. We don't know whether any of those immigrants stayed a while and then joined the emigrants ranks. India has the greatest number of researcher emigrants leaving (~40%) while immigrants relocating to India are almost immeasurable. China is not included because access to researchers there was too restricted (gotta love those Communist regimes).

Banner Ads Available Again

on RF Cafe

I am going to start running private ads in the banner slots again. Since the first of the year I have used just Google, but although the payout is good, I prefer to control which ads appear to visitors. Digi-Key and Avnet type ads are useful, but I don't care for having non-relevant ads taking up space on the pages. If your company can benefit from RF Cafe's exposure to technicians, engineers, managers, students, hobbyists, and a host of other tech-centric people, please check out the advertising information page.

Kim Komando's

Beer Can WiFi Signal Booster

Don't throw that beer can away. You can turn it into an antenna to boost your Wi-Fi coverage. Watch Kim show you exactly how to get it done. Note no sissy butcher's gloves or safety goggles being used by our tech maven maiden - those are for Home Depot ads and handyman magazine articles where marking a piece of wood with a pencil lead that can break is too risky to go without fully body armor.

Amateur Radio Quiz:

Contest Season Refresher

The fall and winter months are packed with contests for every taste: DX, domestic, single-band and specialty events of every stripe. Shake off a little rust with this quiz and get ready to put some QSOs in the log. Remember, too, if you're not a contest aficionado, most major contests use only one mode and 12, 17 and 30 meters bands are entirely contest-free and wide open!

Skyworks Unveils Ultra High

Isolation and Low Loss SP4T

Skyworks has a new 0.02-4.0 GHz, GaAs based high isolation, single-pole four-throw switch with integrated 50 Ω terminations in small 3 x 3 mm quad flat no-lead plastic surface mount technology package.  The SKY13384-350LF is ideal for designs where low insertion loss (<1.0 dB), high isolation (>40 dB) and broadband return loss (15 dB).

Thanks to Colby Instruments

for Continued Support

High-precision programmable delay line (PDL) instruments and modules w/GPIB interface for RF signal applications as phase shifters where extremely high precision accurate delay is required.

Electroluminescence

In 2012, Webster's dictionary defines luminescence as, "the low-temperature emission of light produced especially by physiological processes (as in the firefly), by chemical action, by friction, or by electrical action." Per this 1961 article on electroluminescence in the November 1961 edition of Popular Electronics, Webster defined it back then as, "any emission of light not ascribable directly to incandescence, and therefore occurring at low temperatures." Interesting that the contrast to incandescence is no long used. Maybe in 1960 the phenomenon of electroluminescence was still new and novel enough to emphasize the distinction. Barely a decade had passed since it had moved out of the laboratory and into the marketplace. The ability to economically produce large panels for lighting was deemed...

Sherlock Ohms: The Shortcut

That Shorted Out

Sherlock Ohms is a regular feature of Design News that presents submissions from readers about troubleshooting challenges and how they were solved. This one is titled "The Shortcut That Shorted Out."

Systems Engineer at NASA

Dryden Flight Research Center

Arcata Associates, Inc. has a job opportunity for a Systems Engineer at the NASA Dryden Flight Research Center (DFRC) at Edwards Air Force Base, California. The Systems Engineer position is a mid to senior-level position responsible for defining, designing, and developing system requirements. The incumbent will act as a Project Leader for major product/project designs and implementations.

Science & Engineering Theme

Crossword for 9/2/2012

For the sake of avid cruciverbalists, each week I create a new crossword puzzle that has a theme related to engineering, mathematics, chemistry, physics, and other technical words. You will never be asked the name of a movie star unless he/she was involved in a technical endeavor (e.g., Hedy Lamar).

PMI Intros High-Power

SPST Switch in SM Package

PMI Model No. P2T-14D415D4-15-SMT-20W is a driverless high-power SP2T switch in a compact package designed for surface mount applications. This switch operates from 14.4 to 15.4GHz and has an insertion loss of 1.2dB maximum at +25°C.

Notable [mis]Quote

"I aim at the stars... but sometimes I hit London." - Wernher von Braun (erroneously). Often incorrectly misattributed to von Braun (designer of the Saturn V rocket), it was actually the subtitle suggested (but not official) of a 1960 bio film of his life. The line is credited to comedian Mort Sahl alluding to von Braun's work on the V-2 rocket launched against Great Britain during WWII. However, reportedly the line actually is spoken in the film by a newsman.

Linx and Richardson RFPD

Distribution Agreement

Linx Technologies, a developer and manufacturer of wireless products such as RF modules, announced a distribution agreement with Richardson RFPD, a global electronics distributor that provides deep technical expertise and extensive design support for the latest products from the world's leading suppliers. Richardson RFPD will sell and support Linx modules and Antenna Factor antennas.

Featured Book

Stuff You Don't Learn in Engineering School: Skills for Success in the Real World, by Carl Selinger. "Congratulations! You're an engineer, and now you're ready to take the corporate world by storm. But in order to succeed in your career, you'll need more than just great technical skills."

Please Welcome Baytems

as Our Newest Advertiser!

Baytems designs, develops, manufactures electronic instruments and systems for electronics manufacturers and product testing, development and research. Communication products for the aerospace & defense industries.

Pro-Comm, Inc. Listing Added

RF amplifiers, triode cavity oscillators, sources, transmitters, test equipment for cellular, military, medical, sterilization, for university and private labs. 600-3000 MHz, 500 W peak to 50 kW peak nominal. Design, manufacture and service RF drivers. Repair/refurbish medical RF drivers.

AWR Design Forum 2012

China Registration Opens

AWR Corporation, the innovation leader in high-frequency EDA software, has finalized the agendas and opened registration for the 2012 AWR Design Forums China venues of Xi'an and Chengdu.

Wired Wireless

Adventures of Carl & Jerry

In the continuing saga of Carl and Jerry, our two young electronics hobbyists visit a college radio station where the manager gives a tour while explaining the technical aspects of the equipment. RF bridges, hybrid junctions, oscillator coils and plate-tank pi-networks, cue amplifiers, limiter amplifiers, patch board, power supplies, and a lot of other terms that cause RF Cafe visitors to salivate are woven into the story. Carl and Jerry are surprised to learn that the transmitter output power is high enough that dormitory residents can pick up the signal with "only a pair of earphones clipped across a 1N34 diode" as well as with a standard AM radio. In fact, that's the whole point of the story because the broadcast is not over the air, but via the campus' AC electrical system - hence, "wired wireless." 

Analog Devices' Contest

"Guess the # of Gs"

Dang, I'm not sure how I missed this but Analog Devices ran a "Guess the G's Contest" in a promotion for one of their accelerometers (model # not identified). It was placed in an Estes Big Daddy model rocket and launched on video by Patrick Kusior. Andy Robinson, one of 4,900 entrants, guessed exactly the correct number of 5.561 Gs. He is now the proud owner of an iPad. Watch the video by clicking on the thumbnail above. Another contest will be announced in a couple months.

Video Datasheets for

RF Components

You might have missed the trend, but in the last year or so there has been an increasing practice of component manufacturers creating videos for introducing products to engineers. Typically the videos present not just the charts and tables from the datasheets, but also some info on applications. RFMD s sent me a link for their Video Datasheet for RFVA0016 Variable Gain Amplifier. This will probably become de rigueur for components companies in the future.

IDGA's 9th Annual

Military Antennas Summit

At IDGA's Military Antennas Summit you will learn about the latest technological advancements and capability requirements in the antennas world. The conference will provide a gathering of Senior Executive Personnel from both the military and the industry. This years' event is the only ITAR compliant, US citizens only Summit, where the antennas community can meet and exchange their knowledge and latest improvements.

FCC's Interactive

Broadband Deployment Map

This map was created by the FCC to illustrate the Commission's broadband deployment results found in the Eighth Broadband Progress Report, which uses data underlying the National Broadband Map, as of June 30, 2011. It shows census block areas of the United States with and without access to fixed broadband of 3 Mbps download and 768 kbps upload. The term "rural" used in the key has the same meaning as defined by the 2010 Census. View additional demographic data and broadband deployment by technology by zooming in on and mousing over the specific county...

ACS Intros LINC2 Pro Circuit

Simulator v2.72 Release R

LINC2 Version 2.72R adds many new component models to the program's extensive model library. These include more than 600 new capacitor models, 350 inductor models and a number of new active models including GaN power devices. Also offers enhanced schematic capture.

Articles

- Optimize Signal/Spectrum Analyzer Throughput For High-Volume Manufacturing Test, by B. Nelson

- Fractal Antenna Aims at 2.9 to 14.6 GHz, by I. Srikanth and R. Kumar

- Dual-Band Coupler Links with CRLH Lines

K. Wei, W. Hui, Y. Guo, M. Chen, and W. Wen

Thanks to Dow-Key Microwave

for Long-Time Support

Electro-mechanical & solid state RF switches. Coaxial & waveguide SPDT, DPDT, transfer, multi-position, matrices, multiple-pole, multiple-throw, 12 x 12, 6 x 12, 8 x 16, 32 x 48, custom. Space qualified.

In Memory of Neil Armstrong

Tranquility Base Photo

Apollo 11 astronaut Neil Armstrong died on August 25, 2012. As most Americans over the age of 30 know, Armstrong was the first human to step foot on the moon. On July 20, 1969, in fulfillment of President Kennedy's 1961 challenge to put a man on the moon and return him home safely by the end of the decade, Armstrong made a giant leap for mankind. That day in 1969 I launched an model rocket as part of Estes' commemorative effort. Last night, in his memory, I took this photo of the Tranquility Base region of the moon. Thank-you, and rest in peace, Mr. Armstrong.

Thanks to Empower RF

Systems for Support

High-power solid state amplifiers suitable for virtually any RF, microwave and radar application. Architecture employs full circuit protection against electrical power and RF faults down to the component level.

RF Engineering Theme

Crossword for 8/26/2012

For the sake of avid cruciverbalists, each week I create a new crossword puzzle that has a theme related to engineering, mathematics, chemistry, physics, and other technical words. You will never be asked the name of a movie star unless he/she was involved in a technical endeavor (e.g., Hedy Lamar).

Notable Quote

"It is unfortunate that patent law can be manipulated to give one company a monopoly over rectangles with rounded corners..." - Samsung spokesman re recent lawsuit.

For Sale: 2 GB RAM Modules

for Notebook Computer

These Samsung-K4B2G0846B-HCF8 2 GByte DDR3-1066 SDRAM modules are in perfect condition. I'll sell the pair of them for $15 plus shipping (should be less than $5). Please let me know if you're interested in buying them.

Hittite Intros Low Power,

Wide Bandwidth ADC

The HMCAD1104 is a 10-bit octal channel ADC which offers an industry best combination of low power and high performance. Operating at 65 MSPS, the HMCAD1104 delivers a SNR of 61.6 dB, while dissipating only 30 mW of power per channel.

Featured Book

Software Receiver Design: Build Your Own Digital Communication System in Five Easy Steps,

by C. Richard Johnson Jr., William A. Sethares,

Andrew G. Klein

IEEE Job Resources

• 10 Mistakes to Avoid If You Want a Promotion

• Entry Level Jobs Are No Longer Entry Level

• IBM India Hires More New Women Grads Than Men

Triad RF Systems Intros 40W

1300 MHz Pulsed PA Module

Model TA1004 1300 MHz , 40 W Pulsed PA Module. This L-Band LDMOS amplifier module is ideal for pulsed applications including radar, medical and laboratory applications. This amplifier has several protection circuits including Load VSWR protection, low or high bias protection, reverse bias protection and thermal protection.

Hittite Microwave & Digi-Key

Sign Distribution Agreement

Hittite Microwave Corporation announced the signing of a global distribution agreement with Digi-Key Corporation.  Select Hittite products are now available for purchase through Digi-Key sales channels. Digi-Key will stock Hittite products and offer fast delivery to its global customer base.

Microwave Product Digest

Articles

These articles from the August 2012 MPD might interest you.

- Integrated Low Noise Multi-Chip Amplifier Modules, by S. Moreschi and A. Roy

- Wide BW Measurement Techniques for 802.11ac WLAN Devices, by D. Asquith

- Best Practices for Making the Most Accurate Wireless and Radar Pulse Measurements, by S. Hua Wong and S. Lee

- Minimizing PIM Generation from RF Cables and Connectors, by F. Hull

High Frequency Electronics

Articles

Here are articles from the August 2012 HFE that you might find useful.

- High Frequency PCB Probing with Fixture Removal for Multi-Port Devices (p.24), by H. Barnes, J. Moreira, M. Resso, and R. Schaefer

- Satellite Data Transmitting Systems and In-Orbit Performance (p.36), by

D.V. Ramana and Jolie R.

Thanks to Phase Matrix

for Support!

Frequency counters, upconverters / synthesizers, downconverters / local oscillators, frequency synthesizers, broadband / narrowband oscillators, high-speed clocks, custom RF / microwave subassemblies.

Compactrons:

Advance in Tube Design

In article titled "One Receiver - All Bands" that appeared in the January 1963 Popular Electronics was a single tube design, but the trick to using a single tube was that the it was actually three tubes in one - a 6AF11 compactron. It contained two separate triodes and a pentode within the same glass capsule. A modern equivalent would be to use an IC package that contains three or more opamps in the same package. This article from the October 1960 edition of Electronic World reported on the engineering behind compactrons.

Electronics Measurement Quiz

The early 1960s was evidently a good time for printing quizzes in electronics magazines. Popular Electronics was no exception. As I look through my collection I am finding quite a few. Here is the latest, from the January 1963 edition, that tests basic knowledge of using analog multimeters (digital types were not around yet). I managed to get all the ones I tried correct, but with question 9 I thought maybe it was a trick question, so I didn't bother venturing a guess. Give it a try for yourself.

Webinar: LTE-Advanced

Design & Test Challenges

LTE-Advanced Design & Test Challenges – Carrier Aggregation, Thursday, August 23, 2:00 pm EDT

One Receiver, All Bands

RF Cafe visitor David M. wrote to ask that I scan and post this article from the January 1963 edition of Popular Electronics. It is an article written by Philip Hatfield, of the Receiving Tube Department of General Electric that describe a very simple design that uses a "compactron" vacuum tube, which consist of two triodes and a pentode. The compactron was sort of a vacuum tube version of the multi-amplifier integrated circuit of today. They are still available for purchase on eBay for a couple bucks each.