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|Today in History - 1927: Indian native Narinder Singh Kapany, "the father of fiber optics," was born. 1992: The Vatican admitted erring in formally condemning Galileo Galilei for declaring scientific truths such …||
First Over-the-Horizon TV Bridge
In the days before satellite communications (Telstar I, c1962), long-range television broadcasts relied on an extensive (and expensive) series of line-of-sight microwave towers. Each site had land ownership and maintenance expenses, so there was an incentive to streamline operations. Development of an over-the-horizon relay system enabled a reduction in sites and streamlining of operations - at least in theory. History shows that these installations must not have provided the improvement needed to implement them on a larger scale than that reported here …
Terence, This Is Stupid Stuff - A. E. Housman
Being 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
The 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
This 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
Buckle 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 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
The 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
Unashamedly 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 …
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EE Inventions Connect People & Communities
Infographics are a relatively new medium for presenting a large amount of information in a single graphic using a combination of illustrations and text with numerical data. The format is typically a high aspect vertical ratio banner, which creates a strong visual attraction that suggests a chronological progression. Ohio University’s Master of Science in Electrical Engineering program has created this infographic with the theme "Electrical Engineering Inventions Connect People and Communities." Theirs is not a time progression of inventions, but more of a snapshot of …
A Graphical Look at Daylight Saving Time
Daylight 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
Selenium 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
About 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 56FC, Garod Model 5A1, Admiral Models 7T06, 7T12, Arvin Models 555, 555A, 552N, 552AN, Emerson Models 507, 509, 518, 522, 535. Thanks for your indulgence.
Fire Danger with Lithium-Ion Batteries
Charles 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
If 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
"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, 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
"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
I 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.