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Today in History - 1867: U.S. Bureau of Standards scientist Louis Austin, who pioneered long-range radio broadcasts, was born. 1938: The radio play "The War of the Worlds," starring Orson Welles, aired on CBS. ...

Tech Headline News

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Record-Breaking THz Circuit Could Open New Bands of Spectrum

Satellites Carrying Amateur Radio Payloads Among Those Lost in Launch Explosion

RF and MEMS Technologies to Enable the IoT

1st Commercial Mission to Moon Launched from China

Elon Musk Warns Against Developing AI, Compares It to 'Summoning the Demon'

Smart Watches to Reach over 100M by 2019

Copper Cube Cooled to Near Absolute Zero in New World Record

LG Plans Quantum Dot TVs

Verizon's Changes to Mobile Web Traffic Limit Your Privacy

Mobile Malware Takes Victims by Surprise

Students - Imagination Hosts Robot Programming Challenge

FTC sues AT&T over Unlimited Data Plans

Spooky Wi-Fi Hotspot Name Grounds Plane

You Know You're An Engineer If …

CERN Seeks Help with Photo Archive Captions

How Wi-Fi Is Driving New Competition in the Mobile Market


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A Graphical Look at Daylight Saving Time 

Graphical Look at Daylight Saving Time - RF CafeDaylight Saving Time (DST) ends at 2:00 am local time this coming Sunday morning in most of the U.S., whereupon we return to Standard Time (ST). The event, as with the beginning of DST in March, always elicits a lot of debate over whether DST is necessary in the 21st century. I would prefer to end the inane biannual ritual for reasons illustrated in the graph I created in Excel. Daylight Saving Time is not observed everywhere across the globe, and where it is observed there are variations in when it begins and ends. In the U.S., DST begins the second Sunday of March and ends on the first ...

New Selenium Rectifiers for Home Receivers 

New Selenium Rectifiers for Home Receivers, November 1946 Radio News - RF CafeSelenium rectifiers were the first widely used replacements for vacuum tubes in commercial electronic equipment. Since amplification was not possible - that came in late 1948 with the invention of the transistor, compliments of Shockley, Brattain and Bardeen - diode action in AC-DC power supplies was its primary application. Typical reverse breakdown voltage is in the neighborhood of 20 volts and current handling capability depends on the interface surface area. Cost kept the selenium rectifiers from being widely adapted early in their history (1933), but by 1946 ...

Schematic & Parts Lists for Vintage Radio Sets

Admiral Models 7T06, 7T12 Schematics & Parts List, September 1947 Radio News - RF CafeAbout once a week I post these sets of schematics and parts lists for vintage vacuum tube radio sets. Most RF Cafe visitors have no use for them, but somewhere out there there is probably someone doing a restoration job on one and will be glad to see it. Belmont Model 5P19, Crosley Model 56FCGarod Model 5A1, Admiral Models 7T06, 7T12, Arvin Models 555, 555A, 552N, 552ANEmerson Models 507, 509, 518, 522, 535. Thanks for your indulgence.

Fire Danger with Lithium-Ion Batteries

Fire Danger with Lithium-Ion Batteries (CAFE Foundation image) - RF CafeCharles Murray over at Design News posted a video of a lithium-ion (Li-Ion) battery going up in flames, as a reminder of the potential (pun intended) danger posed by the chemistry used by the vast majority of our portable devices as well as the current fleet of electric cars. In it, a guy whacks an iPad battery pack with a hammer causing it to immediately burst into flames - an act that could easily go way wrong and automatically self-nominate the performer for a Darwin Award. Just as the Ford Pinto and early model Mustangs were discovered to include an unadvertised explode-on-impact feature with ...

Engineering Career Tips for October 28, 2014

Engineering Career Tips for October 28, 2014 - RF CafeIf you are soon likely to find yourself in the position of an interviewer or an interviewee, fear not. There is plenty of advice available for consideration. What you don't say can be as critical as what you do say. As someone who has been the successful interviewee at least a dozen times throughout my electronics career (only one attempt failed), my advice if you don't like rejection is as follows, in order of importance: 1) Do not apply for a position for which you are not fully qualified. 2) Optimize your resume and cover letter for the specific position. 3) Know something about the company's history and ...

Notable Tech Quote: Physicist Richard Feynman

Richard Feynman Notable Quote (UK Telegraph image) - RF CafeThe Feynman Lectures on Physics, boxed set: The New Millennium Edition"It doesn't matter how beautiful your guess is or how smart you are or what your name is. If it disagrees with experiment, it's wrong. That's all there is to it." - Richard Feynman (start video @ 3:52), populist, Nobel Prize winning physicist.

Anatech Electronics' October 2014 Newsletter

Anatech Electronics Newsletter for October 2014 - RF CafeAnatech Electronics, a manufacturer of RF and microwave filters, has published its October 2014 newsletter. As always, it includes both company news and some tidbits about relevant industry events, regulations, and standards. This month, Sam Benzacar offers his views on the subject of "So Many Bands, Too Much Hardware." There are also a couple headlines on MRI on steroids, Biggest wireless job slashers of 2014, microwave device market poised for growth, analysts predicts 2.48% growth in EW spending, and NASA lets you ...

Civilian-Military Service Station

Civilian-Military Service Station, September 1945, Radio Craft - RF Cafe"Use it up, wear it out, make it do, or do without" was more than just a clever slogan during World War II. It was a way of life that extended to both civilian and military realms. While civilians were being both encouraged and compelled to make the most of what was available, military operations were scavenging, borrowing, begging, confiscating, manufacturing, and cannibalizing. France was an important center for not just resurrecting battle-damaged Handi-Talkie and other types of radios, but for taking salvageable components out of unrepairable units. The bit about grinding special crystals for the ...

Engineering Magazine Editor Crossword - 10/26/2014

Engineering Magazine Editor Crossword Puzzle for October 26, 2014 - RF CafeI have to admit to being a bit surprised when creating this crossword puzzle featuring names of editors from the RF and microwave industry's top shelf magazines. In a couple instances I discovered some people I thought were editors are not anymore, and some I did not know were editors now are. Clearly, I need to get out more. This crossword commemorates the efforts of at least eight of those editors. If I remember to do so, maybe next week's theme will be modern technical book authors.

Radio: It's a Piece of Cake

Radio: It's a Piece of Cake - RF CafeThe November 2014 edition of ARRL's QST magazine had a couple photos of some way-cool looking cakes decorated to look like Ham radios. I figured there might be a few more out there so a Google search ensued using "radio cake" as the keywords. "Few" is not the most accurate word for describing the humongous number of radio cakes that have been made. Below is a small sample of specialty cakes you can find just in the Ham and antique radio categories. In the electronics topics alone there are cakes styled after cellphones, computers, telephones, boom boxes, alarm clocks, microwave ovens, ...

** Censored ** 1945 Fusite Advertisement

Cincinnati Electric Products Company Ad Mermaid, January 1945 Radio News - RF CafeI'm guessing once word got out about the Fusite advertisement in the 1945 edition of Radio News, there was a sudden surge of interest in buying electronics magazines by young boys. Even by today's rather loose decency standards this mermaid depiction would undoubtedly cause an outcry. Imagine my shock in turning to page 90 and seeing this illustration! Why, I had to stare at it for many minutes to believe what was before my tender eyes ;-)  Of course since RF Cafe is a family friendly website I did the responsible thing and blurred the offending anatomical portion of Cincinnati Electric Products ...


Terence, This Is Stupid Stuff - A. E. Housman

Terence, This Is Stupid Stuff - RF CafeBeing called a pragmatist is the polite way of saying you are a skeptic, or more seriously, a misanthrope. At various times, I have been called all three (along with a few other choice terms). I prefer to think of myself as guardedly inviting of new ideas and personal acquaintances. It might come with the territory, so to speak, when possessing a stereotypically somewhat introverted 'engineer' personality. I plead guilty and throw myself on the mercy of the court. To do otherwise would be disingenuous. Why bring this up? Something I read this morning reminded ...

Snap Circuits Electronics Learning Kit

Elenco Snap Circuits Lights - RF CafeElenco 130-in-1 Electronic Playground and Learning Center - RF CafeThe main selling point for this Snap Circuits kit is the ability to connect your music to it and cause many different kinds of lighting effects to respond. It is a good way to engage youngsters in electronics design because of the intense visual feedback. Create circuits with included building blocks like transistors, capacitors, LEDs, resistors, switches, motors and more - over 55 parts. There is also the Elenco 130-in-1 Electronic Playground and Learning Center with a more traditional electronics experimenter format that has many more component types. Great Christmas gifts for kids.

Orbital Sciences Antares Rocket Explodes on Launch

Orbital Sciences Antares Rocket Explodes on Launch (NASA) - RF CafeThis really torques me off. The Antares rocket (Orbital Sciences) was originally scheduled to launch Monday evening at 6:45 pm to deliver supplies to the ISS, but was scrubbed 10 minutes before t-0 due to some dumb-a** boater running into restricted waters off the Wallops Island coastline. The explosion occurred Tuesday a few seconds after lift-off. There is a very real possibility that the explosion would not have occurred if the rocket had launched Monday since so many new variables are added after a cancellation.

Standards of Measurement

Standards of Measurement, September 1942 Radio Craft - RF CafeBuckle your mental seatbelt before reading this fast-moving rundown of the origins of many measurement standards used in the cgs (centimeter-gram-second) system. It reminds me of a video you might see of a physics dude 'wowing' an audience of science laymen as he rolls through one topic after another, among them being mass, acceleration, time, electricity, magnetism, solenoids, pendulums, inertia, and gravity. There's nothing you haven't seen and heard before in the first couple chapters of Physics 101 class in the way of equations and drawings, but ...

OK Go - "I Won't Let You Down" Video

OK Go - "I Won't Let You Down" - RF Cafe Video for EngineersOK Go is perhaps best known for sophisticated videos that require extremely high levels of choreography. Their I Won't Let You Down video was posted on YouTube just yesterday and it has nearly 2.5 million views a day later. Back in 2010 I posted their Mousetrap-like This Too Shall Pass video; it now has more than 45 million views. Two major aspects of high technology are featured here: Honda's UNI-CUB β robotic unicycle and the use of a remote control octocopter drone for filming the video. Honda is not selling the UNI-CUB β yet, so the company must have been involved in the effort. The I Won't Let You Down ...

Radio-Craft Incorporating Radio & Television

Radio-Craft Incorporating Radio & Television, November / December 1941 Radio Craft - RF CafeThe announcement of the merging of Radio Craft and Radio & Television magazines into a single publication was made on the eve of America's entrance into World War II. Knowing the visionary talents of publisher Hugo Gernsback, he probably did so at least partly due to what could be predicted as a severe contraction of the domestic electronics appliance market once the war machine gears began cranking. It turns out that he was in fact prescient, because history shows that the government did direct all critical production to military equipment. Buying a new model radio ...

Comics with Electronics Theme

Comics with Electronics Theme - RF CafeUnashamedly I offer up these vintage yet timeless electronics-themed comics for your enjoyment. I freely admit to reaching for the comics page(s) of the newspaper to read the latest antics of Beetle Bailey, Dilbert, Hagar the Horrible, Garfield, Dennis the Menace, Peanuts, Blondie, and many others. As if that was not bad enough in some people's opinion, what would really keep me from getting invited to any more high class dinner parties* if the word got out is the fact that I actually try to spot the 6 differences in Bob Weber, Jr.'s drawings. Melanie and I also like to work the ...

Skyworks Diversity Rx Modules - LTE Smartphones

Skyworks Ramps Revolutionary Diversity Receive Modules for LTE Smartphones - RF CafeSkyworks Solutions today announced that a family of groundbreaking diversity receive modules (DRx) for LTE smartphones is currently ramping with several tier-one manufacturers. This new product category leverages Skyworks’ systems level expertise and techniques developed for cellular base stations to create a highly innovative solution integrating multiple low loss RF switches, receive SAW filters and LNAs ...

Television in Great Britain c1945

Television in Great Britain, January 1945 Radio News - RF CafeTelevision development was a distant memory for most people during the dark days of World War II. Germany's forces launched its second siege of the 20th century against Europe in Fall of 1939. By January of 1945, even the Brits were beginning to feel confident that the seemingly endless days of World War II were about to come to an end. Hitler's forces had been beaten back from its massive sprawl across Europe and into northern Africa. Eisenhower's D-Day campaign six months earlier had broken ...

Satellite Comms Ground and Earth Station Handbook

Satellite Communication Ground Segment and Earth Station Handbook - RF CafeThe Satellite Communication Ground Segment and Earth Station Handbook, by Bruce Elbert, explores the delivery end of the satellite link and its relationship to delivery of services. From international telephone network gateways to direct broadcast home receivers, today's broad range of ground systems and devices require satellite communication engineers and business managers to have a broad and sound understanding of the design and operating principles of earth stations and

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RF Cascade Workbook is a very extensive system cascaded component Excel workbook that includes the standard Gain, NF, IP2, IP3, Psat calculations, input & output VSWR, noise BW, min/max tolerance, DC power cauculations, graphing of all RF parameters, and has a graphical block diagram tool. An extensive User's Guide is also included. - Only $35.
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