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Oxides Used to Flip Graphene Conductivity

Your College May Be Banking on Your Facebook Likes

Next Week's IBM Layoff to Be 'Bloodbath'

Phone Company 'Outraged' by Fraud, Abuse in 'Obamaphone' Program

Entanglement on a Chip Promises Secure Communications, Faster Computers

Photos Show China Military Buildup Near Japan's Senkakus Island

Electronic Circuits with Reconfigurable Pathways Closer to Reality

3-D Transistors Made with Molecular Self-Assembly

Chocolate Shop Sweet Talks Tourists with Bluetooth Beacons

In-Car Semiconductors on the Gas

Big Data Dump Threatened after Malaysia Airlines Hack

Sling TV Could Be Cable-Cutter's Dream

Edward Snowden: iPhone Secret iFeature Allows Government to Spy on You

Internet of Things (IoT) Market to Reach $103.6B by 2018

Stanford Researchers Stack Carbon Nanotubes

Capacitive Sensing Improves Wearable Devices

Graphene Enables All-Electrical Control of Energy Flow from Light Emitters

SIM Card Market Reaches 5.2B Units in 2014

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

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

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


Author: Kirt Blattenberger on Google+ Author:
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Hogarth in Echophone Radio Ads

Hogarth in Echophone Radio Ad, August 1945, Radio Craft - RF CafeHogarth in Echophone Radio Company Ad, June 1945 Radio-Craft - RF CafeHogarth is a comic character invented by the Echophone Radio Company. Their bespectacled Army grunt was one of the first technology nerd types who always managed to appear with pretty girls. His caricature evolved quickly over the two or three year run of the advertisements. Most Echophone Radio ads I have seen either feature Hogarth and his woman/women or Hogarth and a demanding sergeant. This full-page advertisement appeared in the August 1945 edition of Radio-Craft magazine. Echophone radios can still be found on eBay for fairly low prices - often less than the  

Pasternack Announces
New Product Manager

Pasternack Announces Appointment of New Product Manager - RF CafePasternack Enterprises, Inc., a leading manufacturer and supplier of RF, microwave and millimeter wave products, welcomes Mr. Tim Galla as the company's Product Manager for Active RF Components. Mr. Galla brings 25+ years of product development, applications engineering and business development expertise to Pasternack from many of the RF/microwave industry’s most recognized names. Mr. Galla has a successful track record of developing and introducing market-differentiating products and creating new market

War Advertising Council Advice:
Pay Raises Are Bad

Use it up, Wear it out, Make it do, Or do without, January 1945 Radio News - RF CafePay raises are bad for the country. That was according to the Office of War Information's War Advertising Council's full-page spread in the 1945 edition of Radio News magazine. According to their logic, you requesting or expecting - even accepting - a pay raise was damaging to the country's war effort because the ultimate result was increased prices for end users of products and services. It was an argument against inflation at a time when inflation was low . At the time, people had the best interest of the country at heart and, especially with the fate of the free world on the line, were largely willing participants. Having so many family members serving in foreign lands in a battle to beat back

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

Cosmic Radio Signals
from Sun and Stars

Cosmic Radio Signals from Sun and Stars, March 1948 Radio Craft - RF CafeNational defense needs have pushed back the frontiers of science and technology since time immemorial. Mechanics, chemistry, medicine, mathematics, psychology, astronomy, electricity, and as of the late nineteenth century, electronics. Astronomy was useful as a navigational tool and required a very sophisticated knowledge of geometry and algebra to make it accessible to seafaring men, cartographers, and land surveyors. Since the early 1900s, radio astronomy has played a huge role in the advancement of super-sensitive receiver designs. Most people think of information arriving to them in two or maybe three forms: sound, visible light, and some (but not many) even consider radio waves. As over-the-air AM and FM radio broadcasts die out, even fewer people are aware of radio

Career and Job Hunting Advice
January 26, 2015

Engineering Career and Job Hunting Advice for January 26, 2015 - RF CafePlenty of career enhancement and job seeking advice has been published in the ten days since I last scouted out these short articles. Of course there is a lot more where these came from. A caveat emptor warning is prudent when deciding which bits of career coaching prose to take seriously. I routinely detect political and sociological biases and attitudes in way too many.

- Things You Should Never Do
   When Giving a Presentation
- New Year, New Skills: Tech
   Hiring Trends for 2015
- How Job Seekers Can Boost
    Their Communication Skills
- The Highest-Paying States for
   Tech Pros   <more>

Flyback and Yoke Tester

Flyback and Yoke Tester, December 1958 Radio-Electronics - RF CafeHmmm..., I think this article ended up being scanned because an electronics-themed comic appeared on the same page. Oh well, the information about building a simple, one-tube television flyback and yoke tester is still useful to somebody out there, so here it is.

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

Res-Net Microwave Nova Microwave

Electronic, Distributed Configurations

Electronic, Distributed Configurations - RF CafeThe extensive unification of Byzantine fault tolerance and SMPs has investigated flip-flop gates, and current trends suggest that the study of agents will soon emerge. In our research, we verify the evaluation of linked lists, which embodies the essential principles of cryptoanalysis. Here we prove that Markov models and superpages can synchronize to fulfill this objective. Unified ubiquitous communication have led to many natural advances, including the partition table and lambda calculus. In this position paper, we prove the improvement of access points

Notable Tech Quote
David Sarnoff

Notable Tech Quote: David Sarnoff - RF Cafe"Television is likely to do more to revolutionize politics than sound broadcasting did. Political candidates may have to adopt new techniques to benefit from visual radio: their dress, their smiles and gestures, all will be important. How they look, as well as what they say, may determine to an appreciable extent their popularity. The eyes of the public will be upon them." - David Sarnoff, head of RCA, in his annual report on the state of television and radio. March 1948 Radio Craft magazine.

Anatech Electronics Newsletter
January 2015

Anatech Electronics Newsletter: January 2015 - RF CafeAnatech Electronics, a manufacturer of RF and microwave filters, has published its January 2015 newsletter. As always, it includes both company news and some tidbits about relevant industry happenings. This month, Sam Benzacar reports on news about LTE Direct, GaN-on-diamond substrates for high power devices, the World Health Organization findings on RF exposure levels' effects on kids' health, and microwaveable food packet technology. He also opines on the topic of "Interference and the New Year." Being a major manufacturer of filters, Anatech Electronics has a vested

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

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