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Brexit: UK Tech Sector Reacts to 'Leave' Vote

techUK on Brexit: Tech Sector Must Play Its Part

India Launches Record 20 Satellites Aboard Single Rocket

Women Engineers Needed to Address Skills Shortage

Majority of Americans Deny Their Smartphone Behaviors

FAA Issues Commercial Drone Rules

More 5G Spectrum Coming Soon, FCC Chair Says

¼ of Millennials Are OTT-Only Broadband Households

'Space Tsunami' Causes the 3rd Van Allen Belt

Bluetooth Steps Beyond PAN

Atomic Clocks in Space Could Detect Gravitational Waves

The Mechanics of Modulation

The Mechanics of Modulation, October 1931 QST - RF CafePaul Huntsinger wrote a nice introductory article on amplitude modulation (AM) in a 1931 edition of QST magazine. At the time, frequency modulation (FM) was still a laboratory curiosity, and many 'experts' believed that FM would not provide any advantage over AM broadcasting. You might be tempted to think that sources of electrical noise that would interfere with AM were less at the time, thus negating the need for noise-immune FM, but the fact is by 1931 there was a lot of static caused by brushed motors, lousy automobile ignition systems, and arcing transmission lines, along with natural sources like lightning. Figures 6, 7, and 8 were missing in the original article, but fortunately I was able ...

Under a Telephone Pole, by Carl Sandburg

Under a Telephone Pole, by Carl Sandburg - RF Cafe"There is no new thing under the sun." "Everything old is new again." Many such idioms exist regarding how often things tend to run in cycles; it's just that often times people who think they are witnessing a new phenomenon are not aware of the previous occurrences. I have written of examples where 'old timers' lament the attitudes of a fledgling work force when writings show the previous generation of 'old timers' who worked with the current 'old timers' in their youth expressed the same type concern. An article titled "OMG! We've Been Here B4," appeared in the March 2016 issue of Smithsonian magazine ... 

China's BeiDou Navigation Satellite System to Have 35-Satellites by 2020

China's BeiDou Navigation Satellite System to Have 35-Satellites by 2020 - RF Cafe"China's homegrown navigation system, the BeiDou Navigation Satellite System (BDS), will cover the whole globe with a constellation of 35 satellites by 2020, said a government report on Thursday. By 2018, the system is expected to provide basic services to the nations along the Belt and Road, as well as neighboring countries, said a white paper on the BDS issued by the State Council Information Office. China aims to build ..."

LBA Technology Debuts New AM Tower Isocoupler Hardware

LBA Technology Debuts New AM Tower Isocoupler Hardware - RF CafeLBA Technology (LBA), a unit of LBA Group, Inc. announced the next generation of economical AM isocoupler hardware for collocating low power broadcast facilities on AM towers. The LBA research and development team has improved upon the long trusted CAMI™ and CAMIMAX™ with the release of the new CAMI500™, CAMI1800™, and CAMI5000™. While the three new models replace the CAMI™ and CAMIMAX™, LBA will still support the legacy models which are in use around the world. This new line of AM isolation solutions creates more options and opportunities for AM broadcasters to use or offer ...

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FCC Dismisses Petition for Experimental Operation on Amateur Radio Bands

FCC Dismisses Petition for Experimental Operation on Amateur Radio Bands - RF Cafe"The Federal Communications Commission (FCC) has denied two petitions from James E. Whedbee, an amateur radio operator from Missouri. In a June 2016 letter, Scot Stone, Deputy Chief of the Mobility Division explained that the Commission concluded that Whedbee’s petitions did not present enough evidence to merit a rule change. In November 2015, Whedbee requested that the FCC amend Part 97 of its rules to permit amateur radio operators to conduct low-power experiments on amateur frequencies without having to obtain an experimental license ..."

Southern California Amateurs Rise to Earthquake Emergency

Southern California Amateurs Rise to Earthquake Emergency, May 1933 QST - RF CafeThis could be a headline for today, tomorrow, or from 83 years ago. It was the latter, following the magnitude 6.4 earthquake that hit the Long Beach, California region. Per Wikipedia, "An estimated $40M worth of property damage resulted, and between 115 and 120 people died. Many of these fatalities occurred as people ran out of buildings and were hit by falling debris." That paled, though, in comparison to the magnitude 7.8 San Francisco earthquake in 1906, where massive destruction occurred and upwards of 3,000 people died. As usual, radio amateurs were some of the first emergency responders ...

Mac's Radio Service Shop: Barney and the Boosters

Mac's Radio Service Shop: Barney and the Boosters, June 1949 Radio & Television News - RF CafeAs one who recently installed an outdoor antenna with a signal booster on it, I definitely considered whether my exercise and investment would be worthwhile because all the preamplification in the world wouldn't help if the signal-to-noise ratio was lousy to begin with. This statement from Mac McGregor sums it up well, "One thing you have to remember is that the booster has to have something to boost. Unless the antenna can deliver some sort of signal to it, it has nothing to work on. The results are about the same as when a small boy reaches the bottom of his soda. He keeps on trying, but about all his straw delivers is noise ..."

Tips on Technology for Experts in the Courtroom

Tips on Technology for Experts, by IMS ExpertServices - RF CafeWendy Pearson, writing for IMS ExpertServices, offers this article summarizing an expert witness' use of presentation technology in the courtroom - 3D printers, computer simulations, animated graphics, etc. It is hard to believe that in the year 2016 there are still judges that restrict use of high tech methods in the courtroom, but evidently it is so. Anyone old enough to remember when design reviews, seminar speeches, and other presentations to customers and peers consisted of overhead projectors, hard copy handouts, and occasionally a physical sample to pass around to the audience was stand operating procedure, can testify to the vast improvement realized by ...

EU to Spend €1B to Turn Quantum Physics Into Quantum Technology

Europe Will Spend €1 Billion to Turn Quantum Physics Into Quantum Technology - RF Cafe"A 10-year-long megaproject will go beyond quantum computing and cryptography to advance other emerging technologies This dilution refrigerator can cool quantum dots to less than 5 millikelvins for experiments in quantum computing. European quantum physicists have done some amazing things over the past few decades: sent single photons to Earth orbit and back ..."

FCC Proposes 200-MHz Blocks of High-Band Spectrum for 5G 

FCC Proposes 200-MHz Blocks of High-Band Spectrum for 5G - RF Cafe"Federal Communications Commission (FCC) chairman Tom Wheeler this week talked up the role of the U.S. in the development of the fifth generation of mobile technology and proposed new rules designed to free up more spectrum for 5G. FCC commissioners will vote on the proposal on 14 July, Wheeler said in a speech delivered to the National Press Club on Monday, and reproduced on the U.S. regulator's Website. '5G is a national priority,' Wheeler said, having waxed lyrical about the possible applications ..."

RF Cafe Crossword Puzzle for June 26

RF Cafe Crossword Puzzle for June 26, 2016 - RF CafeThis week's RF Cafe Crossword Puzzle is another custom creation (they all are, actually) which contains only words and clues pertaining specifically to engineering, science, mechanics, physics, mathematics, chemistry, and other technical fields of study. If you want to exploit your knowledge of numbnut movie starts, world leaders, and remote villages in BFE, then try the New York Times. Cruciverbalist engineers, technicians, students ...

1 in 15 New Cars to Use Infineon SiGe 77 GHz Radar Chips by End-2016

1 in 15 New Cars to Use Infineon SiGe 77 GHz Radar Chips by End-2016 - RF Cafe"By the end of 2016, more than half of all new automotive 77 GHz radar systems worldwide will be equipped with chips from Munich-based Infineon Technologies, meaning that about one in 15 new cars will use a driver assistance system using its 77 GHz radar chips, says the firm. Infineon's market leadership in the rapidly growing market for radar chips for driver assistance systems was recently confirmed by market research firm IHS Technology. While Infineon has sold a total of 20 million radar chips in the past few years ...

Morsecorp Develops Unmanned Aircraft That Melt

Morsecorp Develops Unmanned Aircraft That Melt - RF Cafe"U.S. military researchers have chosen a third company to develop small unpowered and unmanned aircraft to air-drop small packages for forward-deployed forces. After delivery, the unmanned aircraft melt without any detectable trace to keep them out of enemy hands. Officials of the U.S. Defense Advanced Research Projects Agency (DARPA) in Arlington, Va., added MORSECORP Inc. in Cambridge, Mass., to the Inbound, Controlled, Air-Releasable, Unrecoverable Systems (ICARUS) ..."

VidaRF Offers Wide Selection of Power Dividers/Combiners

VidaRF Offers Wide Selection of Power Dividers/Combiners - RF CafeVidaRF offers a wide selection of 2-way through 16-way power divider / combiners, designed to cover 100 MHz to 20 GHz with average power handling of 30 watts for narrow, octave, dual and multi-octave band applications. Standard Connector type: SMA female, other connectors available upon request. VidaRF is a North Carolina based company that is focused on being a solutions provider by building to customer specs and offering zero days lead time for custom parts through their stock ...

Revolution in the Pythagoras Theorem?

Revolution in the Pythagoras Theorem? - RF Cafe"The Pythagoras theorem has changed. Better yet, our understanding of it has changed from two dimensions to three dimensions. For the past 2500 years, the Pythagoras theorem, arguably the most well-known theorem in the world, has greatly helped mankind to evolve. Its useful right angles are everywhere, whether it is a building, a table, a graph with axes, or the atomic structure of a crystal. What does it look like in 3D? Until now, this ..."

The Reception of Single-Sideband Signals

The Reception of Single-Sideband Signals, November 1952 QST - RF CafeEven though the concept could easily be demonstrated to be viable mathematically, single sideband operation was early on widely regarded as an unrealizable laboratory curiosity, especially with a suppressed carrier. More circuitry is of course needed to accomplish single sideband communications both on the transmit and receive sides, but other than stricter stabilities and precision for frequency sources, single sideband operation is easily obtainable. There still remains a debate over whether voice quality is as good versus ...

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