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Tech Headline News

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Pope: Put Your iPhone Down and Start Talking

Astronomers Study Bizarre Cosmic Radio Burst of Unknown Origin

New Step Towards Using Graphene in Electronic Applications

VHF/UHF/Microwave Conference Seeks Speakers and Papers

1,700 Private Jets Fly to Davos to Discuss Global Warming

Graphene Brings Quantum Effects to Electronic Circuits

New Method to Generate Arbitrary Optical Pulses

Printed Electroluminescent Light Sheets

Australian 'Pico Balloon' Piques Ham Radio Interest

Is Glass a True Solid? (a look at old, ripply window panes shows it's not)

Windows Holographic Is Microsoft's Take on Augmented Reality

Synthetic Diamond Development to Accelerate in 2015

Is Your Online Password on the Worst-Password List?

USAF Launches Rocket Carrying a Navy Satellite

Analysis Shows Way to Self-Propel Subatomic Particles

AT&T, Verizon Challenge FCC's Data Roaming Ruling That Sided with T-Mobile

Industry Standards Eyed for RF and Microwave

How and Why of Frequency
Modulation - Part II

An Engineer Analyzes the How and Why of Frequency Modulation, August 1941 Radio-Craft - RF CafeThis is the second and final installment of an article on the topic frequency modulation that began in the July 1941 edition of Radio-Craft. Author Raymond Guy, a radio facilities engineer at the National Broadcasting Company (NBC), covers all the fundamentals of FM not just from a functional circuits perspective but also pointing out a broadcaster's concern for channel spacing and broadcasting ranges. Transmitter pre-emphasis, receiver de-emphasis, noise thresholds, and adjacent channel and co-channel broadcasting strategies are discussed here.

Career and Job Hunting
Resources for January 16, 2015

Career and Job Hunting Advice for January 16, 2015 - RF CafeInfographics are a big deal in communications these days. A lot of the artwork is really impressive, but let's face it, infographics are basically kindergarten picture books for adults. Even so, I like them - pass the milk and cookies. The first item on this week's list is in fact an infographic with recommendations on avoiding resume mistakes. Don't expect a 'wow' factor in the pictures, though; it looks as though everything came from the MS Office clipart collection.

- Resume Mistakes Job Seekers
   Must Avoid [Infographic]
- How to Ask for a Raise – and
   Actually Get It
- The Single Best Way to
   Answer Every Job Interview
- My First 90 Days: Interview Is
   Just Beginning<more>

Google's Spiral 2
Modular Smartphone

Google's Spiral 2 Modular Smartphone - RF CafeA lifetime ago (in technology advancement time units) I reported on a crowdfunded project to develop a modular smartphone called Phonebloks. The idea was to sell a plug-and-play building block platform where the user decides exactly what functionality he/she needs and what level of functionality, and then simply plugs the modules into a motherboard type base. It would also permit owners to upgrade and/or swap out only functions deemed necessary. So, if you believe that a 12 Mpixel camera sensor chip being used with a cheap plastic lens is an unwarranted expense, then buy the 5 Mpixel camera module with the same lens and same picture quality for half the price, and at the

Have You Seen Him?

Have You Seen Him?, April 1935 Short Wave Craft - RF CafeToday we have missing persons notices printed on milk cartons and computer-aged pictures of missing kids on bulletin boards at Walmart, and of course the Internet with all its various forms of publicity. In 1935, evidently, an electronics magazine was a proper venue for placing a missing person ad. At the time there was no convenient and accessible way for family members to reach out to a nationwide audience other than to place ads in magazines and/or newspapers in remote locations. I thought it odd to see such a placement in this edition of Short Wave Craft, but considering the aforementioned, doing so is entirely reasonable for a worried family. It's heartbreaking, really

Author: Kirt Blattenberger on Google+ Author:
Kirt Blattenberger

RF Cafe's Final Engineering
Crossword Puzzle

Amateur Radio Crossword Puzzle for January 25, 2015 - RF CafeThis is likely the last engineering-themed crossword puzzle that I will be creating. It takes about an hour to make and publish each one, and since I suspect the number of dedicated cruciverbalists out there are few, it is just not worth the effort anymore. Without any memorable exceptions, I have created a crossword puzzle every week since sometime in the year 2000 (more than 700 total). Each one was made with personally selected words to avoid non-relevant terms and clues. The puzzles will resume if enough requests come in to do so, otherwise, today marks the end of an era.

Electronics-Themed Comics

Electronics Themed Comics, August 1944 Radio Craft - RF CafeIt's Friday and the weekend is almost here - time for little levity. These comics from Radio-Craft magazine have an electronics theme, so you can claim looking at them is work-related since you might use one for your next conference or project status presentation. Some of the concepts are utterly foreign to contemporary readers, like user-serviceable electronics apperati[sic] and radio sets that receive over-the-air signals. There is a list of many more similar comics at the bottom of the page in case you haven't seen them yet. Enjoy

Police Radar That Sees
Through Your House Walls

Police Radar That Sees Through Your House Walls - RF CafeL3 Comms' Range-R handheld radar unit is capable of 'seeing' through building walls to detect a building's contents. It was evidently developed for military operations when conducting house-to-house searches for jihadist terrorists in places like Afghanistan and Iraq. Like much military technology, though, it is being adopted for use by civilian police, federal law enforcement agencies, firefighting, and search & rescue teams. Range-R's ability to "detect and measure the distance to moving and near-stationary personnel through walls constructed of common building materials" makes it an ideal tool for looking for survivors inside collapsed buildings, for finding incapacitated and/or trapped people within burning homes, and for allowing law enforcement personnel to determine the presence and

Balloons Raise Shortwave

Balloons Raise Shortwave Antenna, April 1935 Short Wave Craft - RF CafeAntennas have been deployed in difficult environments using many ingenious methods over the years both by professionals and amateurs. The process typically involves first propelling a lightweight string or wire across and/or up to a supporting structure (a tower, tree, building, whatever) and then using that lead line to draw the antenna and its accompanying coaxial or twin lead cable into its final position. Sometimes simply tying a line to a rock and tossing it over a tree branch does the trick, but usually deployment requires a more powerful launch such as a a bow and arrow or even a model rocket. Many years ago a modeling magazine reported on a large radio controlled airplane that towed a lead line across a wide gulch

Notable Tech Quote for
Week of January 20, 2015

H. Ward Silver quote, January 2015 QST - RF Cafe"Earth is not a magic drain into which all of unwanted RF can be poured via a wire." -- H. Ward Silver, N0AX, ARRL author of "Hands-On Radio" column in QST (January 2015). Mr. Silver is also the lead editor of the ARRL Handbook.

An Engineer Analyzes the How
and Why of Frequency Modulation

An Engineer Analyzes the How and Why of Frequency Modulation, July 1941 Radio-Craft - RF CafeHere is the first of a two-part article on frequency modulation. FM was a very welcome option for entertainment radio listeners who had grown weary of static mixed in with their music and syndicated adventure, drama, and comic programs like The Green Hornet, Lights Out, and The Life of Riley, respectively. Amplitude modulation is susceptible to all sorts of interference from car ignition systems, arcing in electric motors, light switches being turned on and off, lightning, and a host of other sources. A commercial radio with good noise and adjacent channel rejection was relatively expensive. Permanent magnet speakers did not become a standard feature for first few

How Many Microhenrys
in That Coil?

How Many Microhenrys in That Coil?, December 1931/January 1932 Short Wave Craft - RF CafeThis is a nice short article covering the calculation of inductances for coils wound on cores and wire sizes. The author recognized that standard formulas, although concise and accurate, are sometimes difficult to work with when calculations for a large number of values is needed for a particular circuit design. To address the situation, he presents a handy nomograph, chart, and a table of typical values. A smartphone app, a spreadsheet, or a desktop computer program would be toay used to calculate inductance values, number of turns, winding spacing, etc., but back when mechanical slide rules were the order of

Carl & Jerry:
Operation Worm Warming

Carl & Jerry: Operation Worm Warming, May 1961 Popular Electronics - RF CafeWhen becoming a licensed Ham a few years back, I learned that when broadcasting over amateur bands, the FCC requires you to transmit your station identification at the beginning of each session and then at least once every ten minutes. I hate to nit pick a Carl & Jerry story, but in this episode John Frye's intrepid electronics hobbyist duo rigs up their basement 'shack' to automatically transmit the letter 'A' in Morse code as a beacon signal to test reception in a cave. A timer would start the broadcast and it would run continuously for half an hour. Maybe things were different in 1961. The experiment intended to test a signal's ability to propagate through the Earth rather than through the air. It is an interesting twist on the skin effect of high frequency signals along a conductor

Free Subscriptions
to Engineering Magazines

January 2015 Free Engineering Magazine Subscriptions - RF CafeMany of your favorite magazines offer free subscriptions to qualified applicants. Qualified usually means that you are currently employed in a field related to the primary theme of the magazine, and often you also need to be a decision maker for buying products represented within the pages. The list hasn't changed much - if at all - since last month. Technical magazines, like RF Cafe, get paid by advertisers and therefore need the public to support those companies by purchasing their products and/or services. If you think you meet the standards

The Latest Engineering Articles

The Latest Engineering Articles (1-20-2015) - RF CafeI know you're busy, so I took the liberty of linking to a few recent articles from Microwave Journal, High Frequency Electronics, and Microwaves & RF that look interesting. That's not to say the others are not, but this is the kind of stuff that piques my curiosity. The overly scholarly articles make my head hurt, so I gravitate toward practical advice and whiz-bang new technology.

- Wideband Omnidirectional
   Microwave Cloaking, N. Cohen
- Sorting Through Balun
   Confusion, D. Jorgesen
- Changing the Operating
   Frequency of an RF Power
   Amplifier Circuit, (p.22)
   D. Vigneri
- Real Time Radar Target
   Generation, S. Heuel,
   D. McCarthy
- Antenna Tackles Wi-Fi and
   WiMAX, M. Shafiei,
   M. Moghavvemi, W. Mahadi

EDI CON Adds 5G Advanced
Communications Forum

EDI CON Adds 5G Advanced Communications Forum to Conference Sessions - RF Cafe
Horizon House Publications and Microwave Journal China are pleased to announce that EDI CON 2015, taking place April 14-16, has added a 5G Advanced Communications Forum to the conference schedule. The 5G Forum will be a full day of sessions taking place on April 15 at the China National Convention Center . The 5G Forum will kick off with China Mobile presenting their perspective on 5G technologies followed by a panel session including experts from organizations such as China Mobile, Shanghai Tech, Keysight Technologies, Rohde & Schwarz and National Instruments. A

Res-Net Microwave Advanced Test Equipment
Nova Microwave

Unique Sound Effects in Radio

Unique Sound Effects in Radio, February 1939 Radio-Craft - RF CafeSound effects in television and movies are in the modern era generated electronically at the push of a button or the clicking of a mouse. Thousands of sound effects are available for download to enhance amateur videos. Whether you need the clopping of horse hooves, birds chirping, a street racer squealing his wheels coming off the starting line, or a baby crying in the background, it's all at your disposal - and usually at no cost. Prior to around 1960, with the exception of the incredibly phony sounding 'canned' laugh tracks and audience clapping used on 'live' situational comedies and variety shows, all those aforementioned sound effects had to be created real-time in the recording studio. Even if you are too old to have actually listened to old time radio shows like The Lone Ranger and The Shadow, surely you have watched an old movie where a gun shot was heard

Radio in the Next War

Radio in the Next War, May 1948 Radio Craft - RF CafeIn his 1948 editorial titled "Radio in the Next War," Hugo Gernsback predicted no fewer than four major technological milestones. The first two were actually foreseen in his pre-World War II articles where he wrote of what would become known as 'radar' and the 'Handie-Talkie.' With war against the Commies in North Korea brewing, he wrote of both cruise missiles, NORAD, and the concept of MAD (Mutually Assured Destruction) as it pertained to the U.S. now being the first to detonate a nuclear weapon henceforth. For more than 70 years the prediction has held. You need to be a pretty good judge of both technical capabilities and their developmental

And Now - The Filamentless Tube

And Now - The Filamentless Tube, March 1933 Radio-Craft - RF CafeIf this article had appeared in an April edition of Radio-Craft, I might have suspected it was a Fool's hoax, but it was the March issue and, it turns out, it was serious. Obviously the concept of a filamentless tube did not work out well since the overwhelming majority of vacuum tubes sold up until the time semiconductors took over the electronic device market had separate filaments (heaters). It was a great idea, though, and the world is thankful for the pioneers who take the figurative 'arrows' for the rest of us. We benefit from their hard work and ingenuity, while they suffer the agony of defeat, with an occasional taste of the thrill of victory. It is too bad the concept did not work because, as pointed out in

Guerrilla RF's New Ultra-Low
Noise Amplifier Family

Guerrilla RF's New Ultra-Low Noise Amplifier Family Features Industry Leading Noise Figure and Highest Level of Performance - RF CafeGuerrilla RF Inc., a leading provider of high performance MMICs, today introduces an ultra-low noise amplifier family with industry-leading noise figure and the highest level of performance. These new high linearity solutions support a number of wireless infrastructure devices including high performance small cell LNAs, macro base station LNAs, distributed antenna systems (DAS) and general purpose LNA applications requiring the absolute lowest possible NF. "We are excited to help our wireless infrastructure customers obtain maximum receiver sensitivity and improve receiver dynamic range with minimal external components, which ultimately

The Homeowner's DIY Guide
to Electrical Wiring

The Homeowner's DIY Guide to Electrical Wiring - RF CafeDavid Herres has sharpened his pencil and written a couple new books for the DIYer tackling electrical wiring issues at home. The Homeowner's DIY Guide to Electrical Wiring goes beyond the typical book of this sort and devotes considerable space to modern electrical devices like wide screen TVs, computers, wireless devices, alternative energy, home automation, satellite receivers, etc. He also discusses electrical services, specialty devices like ground fault and arc fault interrupters (GFIs and AFIs), recent National Electrical Code changes, and much more. Stay tuned for a review and accompanying quiz on David's The Electrician's Trade Demystified.

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