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"Those who cannot remember the past are condemned to repeat it." - Santayana

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Tech Headline News

- Archives -

Qualcomm Demos 3D Fingerprint Technology for Mobile Phones

Safety Worries Lead Airlines to Ban Li-Ion Battery Shipments

Geneva Auto Show Worries About Silicon Valley

U.S. Needs a Mars Colony, Buzz Aldrin Tells Senators (Disney's Buzz Lightyear named after him)

ARRL 2015 Field Day Gear, Supplies Now Available

The Slow Death of Hardware Design

Woman Reunited with Stolen iPhone When Idiot Thief Posted Selfie on Her Facebook Page

Prepare for 'The End of College' as You Know It

Blackberry Unveils 'Leap' with No Physical Keyboard

Supreme Court Backs Trade Group’s Challenge to Internet Sales Tax Law

WordPress to Remain Most Attacked Platform

California Homes Raided in Investigation into Chinese ‘Birth Tourism’ (...while CA invites Illegal anchor babies from Mexico & SA - racism?)

Counterfeit Components Continue to Slam Electronics Industry

Air Force Weather Satellite Explodes in Orbit (since when do those things just explode? global warming caused it?)

Boeing’s First Two All-Electric Satellites Ready for Launch

Ikea Turns Furniture into Wireless Phone Chargers

Magnetic Hammer

Magnetic Hammer, January 1965 Electronics World - RF CafeIf you ever have the opportunity to read the history of the engineering efforts that went into designing and building the Saturn V rocket, you will be amazed at the ingenuity and incredible work that went into its creation. Margins of error approached single digits in some instances, like with some of the fuel tanks. According to the book NASA Apollo 11: Owner' Workshop Manual, re-design was constantly required to remove weight from already-completed assemblies in order to compensate for overweight components that could not be kept within their budget allocations. Some portions of fuel tanks were so thin that a finger poke would deform the container. This news item from a 1965 edition of Electronics World

Chinese Vacuum Tubes

Chinese Vacuum Tubes, October 1945 Radio News - RF Cafe1945 or 2015? Seventy years have passed since this photo of a vacuum tube manufacturing facility in China was taken. Given that most new vacuum tubes are made in China, and that the labor work conditions have not changed much in the intervening time period (except in high-profile plants like Foxconn where Apple products are made), this might very likely represent a modern day operation. BTW, most of the vacuum tubes not being made in China are made in Russia... to assure their antiquated infrastructure has an ample supple of replacement parts. I say that only partly in jest. The largest market for new vacuum tubes is music amplifier equipment and a few

Author: Kirt Blattenberger on Google+ Author:
Kirt Blattenberger

Vintage Amphenol
Coaxial Cable Advertisement

Amphenol Advertisement, October 1945 Radio News - RF CafeAmphenol has been around since 1932, when founder Arthur Schmitt offered sockets for vacuum tubes. Now headquartered in Wallingford, CT, the company began life in Chicago, Illinois. Amphenol was a major supplier of coaxial cable in the days when most of the cable Americans used was produced in the country. Alpha Wire, Amphenol, Carol Cable (now part of General Cable), and General Cable are the names that come to mind that were around in the 1970s when I entered the radio-electronics realm. The radar system I worked on in the USAF, and all of the defense electronics electronics systems I worked on as a technician and engineer, used those four brands. Today, of course, there is a seemingly unlimited number of coaxial cable

Training with Visual Aids

Training with Visual Aids, October 1945 Radio News - RF CafeLong before there was Power Point (OpenOffice's Impress is the free equivalent), presentations at training seminars were conducted using overhead projectors and larger-than-life props of the devices being taught. The U.S. Navy, during World War II, set up a special facility called the Visual Aid Model Shop located at Radio Chicago, Chicago, Illinois. Its charter was to design and build very large scale models of equipment and tools that service personnel used while performing their duties. It is kind of funny to look at the sizes of some of the items, like the 8x size radio chassis assembly shown in this article's main photograph. As a life-long model builder myself, I would have loved to work in a shop

NI AWR Design Environment
Application Note Now Available

NI/AWR "How to Improve Second-Harmonic Passband Rejection Microstrip Side-Coupled Filters" - RF CafeNI (formerly AWR Corporation) released a new NI AWR Design Environment application note, “Improving the Second-harmonic Pass Band Rejection of Microstrip Side-coupled Filters.” Because of their low cost and easy manufacturability, side-coupled filters constructed from printed-circuit board-based microstrip are widely used throughout the industry. One of the main drawbacks of the side-coupled filter is its limited rejection of the second harmonic. This application note demonstrates a solution that mitigates this problem through the introduction of notch-filter elements that improve the overall rejection of side-coupled filters at the second harmonic without significantly affecting the filter passband behavior

See The Full-Page Splash Ad
You've Been Missing on RF Cafe

Website Entry Screen Splash Advertising - RF CafeAre you kidding me ?!?!?! Why in the world would you WANT to see a full-screen splash ad when you visit any website? I absolutely detest those things. When I visit a website, I want the first thing I am presented with to be the content of the site, NOT a full-page advertisement with some lame message like, "Please wait while your page is loading," or "Welcome Screen," or some other annoying and/or disingenuous text. Do the webmasters really think visitors are stupid enough to believe that the website's real content is loading behind the advertising screen, and that they are doing visitors a favor by providing

Poll: Which OS Does
Your Phone Use?

Official RF Cafe Website Poll

RFMW SM Iso-Attenuator for
High Power Circuit Protection

RFMW Offers Surface Mount Iso-Attenuator for High Power Circuit Protection - RF CafeRFMW announces design and sales support for the Iso-Attenuator model RFSL2308-A30 from RF Circulator Isolator (RFCI). RFCI Iso-Attenuators combine protection for active components from distortion or potentially damaging reflected power with a convenient, attenuated port for monitoring RF power or providing a feedback loop. The RFSL2308-A30 is capable of handling 1000 W peak / 200 W average forward power and 100 W CW reverse power into the on-board, 30 dB attenuator. Spanning 2200 to 2400 MHz, the RFCI RFSL2308-A30 provides >25 dB typical port-to-port isolation

February 2015 Book Drawing
Winners Have New Selection

Thanks to Qorvo's Jeff Cameron, Sr. Manager, Product Marketing, Filter Solution, for providing this very high quality polo / golf shirt (made by the Pebble Beach brand) with a Qorvo company logo embroidered on the front. It is being offered as a prize selection in the monthly RF Cafe Book Drawing. I knew Jeff back in the early / mid 2000s when I worked for RF Micro Devices in Greensboro, NC. As you probably know, RFMD merged with TriQuint last year and became Qorvo. Both of February's winners have been notified, but I haven't heard back yet from either. The shirt might be gone before the March drawing occurs.

Radar Engineering Crossword
Puzzle for March 1, 2015 

Radar Engineering Crossword Puzzle for March 1, 2015 - RF CafeI stopped creating the RF Cafe engineering and science themed crossword puzzles at the end of January in order to test the interest in them. As of today, on March 1st, I will resume creating them every couple weeks. It takes up to an hour to make each crossword. Enjoy this radar engineering themed puzzle.

Electronics-Themed Comics

October 1944 & May 1945 Radio-Craft - RF CafeIt's Friday again already (...finally). In that these comics from Radio-Craft magazine have an electronics theme, you can claim looking at them is work-related. You might consider using one of them for your next conference or project status presentation. There is a list of many more similar comics at the bottom of the page in case you haven't seen them yet. Enjoy.

Terahertz Metrology

Terahertz Metrology - RF CafeTerahertz Metrology, by Mira Naftaly. "This new book describes modern terahertz systems and devices and presents practical techniques for accurate measurement with an emphasis on evaluating uncertainties and identifying sources of error. This is the first THz book on the market to address measurement methodologies and issues - perfect for practitioners and aspiring practitioners wishing to learn good measurement practice and avoid pitfalls. This book provides a brief review of different THz systems and devices, followed by chapters detailing the measurement issues encountered in using each of the main types of THz systems, and a guide to performing measurements rigorously. Particular attention is given to evaluating

Notable Tech Quote:
- Marshall McLuhana

Herbert Marshall McLuhan - RF Cafe"Xerography is bringing a reign of terror into the world of publishing, because it means that every reader can become both author and publisher." - Marshall McLuhana, 1966, from March 2005 Smithsonian magazine. An unregulated Internet provided the next step in that freedom. On February 26, 2015, the FCC adopted "Net Neutrality," giving the Federal government control over the Internet under the guise of protecting little 'ol you. Be sure to thank the people you know who voted for the people who passed this. If you think you're being spied on now, you ain't seen nothin' yet.

Intermediate Engineer:
Embedded Hardware/Software
and Mixed Applications

Synergy Intermediate Engineer Job Opening:  Embedded Hardware/Software and Mixed Applications - RF CafeSynergy Microwave currently has an opening for an Intermediate Engineer: Embedded Hardware/Software and Mixed Applications. A very exciting opportunity to join a strong engineering team dedicated to developing radio frequency products for the microwave communication, microwave instrumentation, radar and defense applications. You will have extremely deep resources and guidance for modern radio product development using mixed signal and digital radio techniques. Qualifications include experience in radio frequency applications, modulation algorithms, signal detection, leveling and

Theory and Practice

Electroluminescence: Theory and Practice, January 1965 Electronics World - RF CafeElectroluminescent (EL) devices were patented by General Electric back in 1938, but it was not until the 1960s that the fabrication process, involving copper-doped zinc sulfide (ZnS) as the light-emitting compound, had developed to the point where high volume production was feasible. Early EL displays exhibited short lifetimes and low efficiencies. EL panels are also referred to as light-emitting capacitors because of their construction geometry. Some of the first commercial applications for such EL panels were as back lighting in automobiles. Electroluminescence can also be obtained in semiconductors in the III-V group class like indium phosphide (InP), gallium arsenide (GaAs), and

Your RF Cafe
Progenitor & Webmaster

Click here to read about RF CafeKirt Blattenberger… single-handedly redefining what an engineering website should be.

View the YouTube RF Cafe Intro Video Carpe Diem!
(Seize the Day!)

5th MOB: My USAF radar shop

Airplanes and Rockets: My personal hobby website

Equine Kingdom: My daughter Sally's horse riding website