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Click here to read about RF CafeKirt Blattenberger

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"The only way to predict the future is to invent it" - Alan Kay, father of OOP

Today in Science History

High Tech News
- Headline Archives -

Taking the Stigma out of Buying Used Electronics

World Wide Repeater Directory Now Lets Users File Jamming Reports

Zuckerberg Spent $19M on Security in Past 3 Years (guns OK for Mr. Facebook, but not you and me)

Radio Spectrum in Latin America Far from Ideally Allocated

Researcher Accidentally Develops Way to Make Batteries Last 400x Longer

The Day After the iPhone Fell

Samsung Holds Lead in Flat Global Smartphone Market

Comcast Bumps Its Trial Data Caps to 1TB

The Secret of NASA's 'Impossible' Fuel-Free Thruster?

Smartphone Shipments Fall to 292M in Q1, iPhone Plunges 44%

Much Appreciation for Windfreak's
Continued Support!

Windfreak TechnologiesWindfreak Technologies was created with the vision of providing low cost, quality, innovative RF products that can be SynthNV: 34 MHz – 4.4 GHz RF Signal Generator w/ Power Detectorused in a wide range of highly technical applications for a wide range of customers, from hobbyists to education facilities to government agencies. Windfreak designs, manufactures, tests and sells high value USB powered and controlled radio frequency products such as RF Signal Generators, RF Synthesizers, RF Power Detectors, RF Mixers, RF Upconverters and RF SynthUSBII: 34 MHz – 4.4 GHz Low Cost RF Signal Generatordownconverters. Worldwide customers include Europe, Australia, and Asia. Please visit Windfreak today!

Micro-Sized Liquid-Metal Particles
Created for Heat-Free Soldering

Micro-Sized Liquid-Metal Particles Created for Heat-Free Soldering - RF Cafe"Martin Thuo likes to look for new, affordable and clean ways to put science and technology to work in the world. His lab is dedicated to an idea called frugal innovation: 'How do you do very high-level science or engineering with very little?' said Thuo, an assistant professor of materials science and engineering at Iowa State University and an associate of the U.S. DoE's Ames Laboratory. 'How can you solve a problem with the least amount of resources?' That goal has Thuo and his research group their materials expertise to study soft matter, single-molecule electronics and renewable ..."

Editorial re FCC Potentially Shutting
Down Amateur Radio During WWII

Editorial on FCC Potentially Shutting Down Amateur Radio During WWII, November 1940 QST - RF Cafe"Do you think that F.C.C. would be engaged in the present terrific expense and effort of getting our fingerprints and citizenship histories if there were intention of shutting us down shortly?" That statement was printed by the QST magazine editor in the issue that preceded the December 7, 1941, attack on Pearl Harbor by thirteen months. A few things about it are troubling. First, the FCC was collecting fingerprints of licensed amateur radio operators. Second, the FCC was assimilating information about licensed amateur radio operators' citizenship histories. Third, a combination of short-sightedness and apparent naiveté concerning the FCC's willingness to shut down amateur radio operations once ...

Graphene Doped with Hydrogen
Reveals Its Magnetism

Graphene Doped with Hydrogen Reveals Its Magnetism - RF Cafe"Hydrogen atoms can induce magnetism in graphene and be used to create a uniform magnetic order across the 1D material. That is the finding of researchers in Spain, France and Egypt, who also demonstrated that it is possible to atomically manipulate hydrogen atoms on graphene to control the local magnetic state. Graphene is a sheet of carbon just one atom thick that has a number of unique properties. But it is not magnetic. 'The incorporation of magnetism to the long list of graphene capabilities ..."

The "Fair Use" Doctrine
and the U.S. Copyright Office

The "Fair Use" Doctrine and the U.S. Copyright Office - RF Cafe"The Congress shall have Power … To promote the Progress of Science and useful Arts, by securing for limited Tımes to Authors and Inventors the exclusive Right to their respective Writings and Discoveries." - United States Constitution, Article I, Section 8. Therein lies the authority for legislation and prosecution of rights for virtually every human creation within the jurisdiction of the country. Each nation has it own version, and international agreements help assure universal protection of a creator's rights of ownership; e.g., the "Convention for the Protection of Literary and Artistic Works" of 1886 and the World Intellectual Property Organization. America has the U.S. Copyright Office. Those of us involved in presenting information and referring to legally protected ...

Thomas Edison in John Hancock Ad
in The Saturday Evening Post

Thomas Edison in John Hancock Advertisement from the April 29, 1950 The Saturday Evening Post - RF CafePresenting yourself or your company as being modeled after a person of great accomplishment has been a common promotional tactic for as long as there has been print media. The John Hancock chose in this issue of The Saturday Evening Post to suggest, albeit by an indirect approach, to elicit the admiration Americans had for Thomas Edison's lust for innovation and desire to make people's lives better in hopes that readers would associate Edison with the insurance company. While the juxtaposition is strained, I do like one line in particular, "He lured electricity into a bottle and taught it to glow with good cheer." This short tribute to on of the world's greatest engineers is worth your a few moments of your valuable time ...

Cobham Universal Spring Mount
Antenna Range Sticks Its Neck Out

Cobham Universal Spring Mount Antenna Range Sticks Its Neck Out - RF CafeCobham Antenna Systems announces the launch of a dual-band, Gooseneck addition to the 'Universal' spring mount range of omni-directional antennas. The Gooseneck antenna, along with a selection of the 'Universal' spring mount antennas, will be available to view on Cobham's booth #1319 at (AUVSI's) XPONENTIAL 2016 in New Orleans, Louisiana. The OA2-2.3V-5.2V/2358 is a ground plane independent, dual band antenna which covers the frequency ranges 2.10 – 2.60 GHz and 4.40 – 6.00 GHz, offering 4 dBi gain in the higher frequencies ...

The Wives and Mothers
of Radio Amateurs

The Wives and Mothers of Radio Amateurs, August 1931 QST - RF CafeHow well received do you think this social concept would be in today's easily offended world: "To bring together socially the Wives and Mothers of Dallas Radio Amateurs; to promote mutual sympathy, counsel, and interest in our husband's and our son's hobby; and with a realization that theirs is an outstanding, fascinating, far-reaching and educational hobby, it is our desire to further their interests in whatever way may present itself." It would be roundly criticized as a backward, misogynistic, 1930-era mindset intended to subject women to yet another form of domestic slavery beyond housekeeping and child rearing - no doubt thought up by a man. Anyone thinking so ...

Tesseract Antique Instruments

Tesseract Antique Instruments - RF Cafe SmorgasbordMy introduction to a tesseract was during an episode of Carl Sagan's "Cosmos" series in the 1980s, where he was demonstrating how beings in of dimension N would perceive items of dimension N+1. The tesseract, Sagan explained, is a 3-dimensional projection of 4-dimension hypercube. Watch the embedded video for more information. The Tesseract website, which has nothing to do with a hypercube as far as I can tell, deals in some very cool antique scientific instruments. I learned of it from an article in Astronomy magazine where an editor recommended it when researching the potential value of a collectible telescope. Run by Drs. David and Yola Coffeen, Tesseract has a huge inventory of items ...

Multi-Impedance Dipole Antennas

Multi-Impedance Dipole Antennas, May 1953 QST - RF CafeMaybe I suffer from cranial rectumitis at the moment, but I'm having a hard time with a statement made about coaxial feedline impedance, to wit, "102-ohm line (52-ohm lines in series)." I must be missing something because I don't understand how placing two 52-ohm transmission cables in series results in twice the impedance. Aside from that, author John Avery presents an interesting article on multi-impedance dipole antennas. Empirical data is presented on how the feedpoint impedance of a dipole varies with distance above the ground. His results are very close to theoretical values which assumes non-sagging elements, perfectly linear alignment, a perfectly conductive ground, etc. He then extended his investigation into 2-wire (4x impedance) ...

Physical Layer Measurement for Next
Gen 5G/IoT Wired Communications

Physical Layer Measurement for Next Generation 5G/IoT Wired Communications - RF CafeFree downloadable whitepaper from Anritsu. "This paper outlines some high-speed standards for next-generation communications and describes some physical-layer measurement techniques, targeting the era of 5G and IoT. • Need for 5G/IoT Generation • Wired Networks Faster • Wired Communications Measurement Challenges in Next-Generation Interconnects ..."

Air Force Needs Antennas for Future
High-Power Microwave Weapons

Air Force Looking for Power Sources and Antennas for Future High-Power Microwave Weapons - RF Cafe"U.S. Air Force researchers are asking industry to develop power sources and antennas for future high-power microwave weapons and for other aerospace and defense uses. Officials of the Air Force Research Laboratory at Kirtland Air Force Base, N.M., released a solicitation Tuesday for the source and antenna portion of the High-Powered Electromagnetics (HPEM) research program. The overall HPEM project seeks to develop high-power electromagnetics technologies not only for directed-energy weapons, but also for cyber warfare, EW, electronics-killing weapons ..."

API Intros Miniature, In-Line,
Coaxial Rotary Joints

API Technologies Miniature, In-Line Rotary Joints - RF Cafe"API Technologies offers a standard line of rotary joints, formerly manufactured by Sage Labs, suitable for use in commercial and military applications. The term rotary joint describes a device used to transmit energy from a stationary RF line to a rotating RF line." The 345 and 351 series covers DC to 40 with VSWRs in the 1.2:1 to 1.75:1 range. Peak power handling is 500 W. Max rotation rate is 100 rpm. SMA & 2.92 mm connectors. WOW is the per revolution variation, same as with audio equipment ...

The Auto Industry's Latest
and Greatest Engines

The Auto Industry's Latest and Greatest Engines - RF CafeI've said before that if you want a place to see great engineering-related slideshows, it's hard to beat the subjects that Charles Murray and Rob Spiegel come up with on the Design News website. Motorheads will definitely appreciate these images of some of the most high-tech production engines ever built. The blue anodizing on Ford's 1.0-liter, turbocharged, three-cylinder EcoBoost engine is incentive to do like in the 1950s-70s and cut a hole in the hood to show off the craftsmanship. However, its diminutive size would allow it to fit into an airplane's overhead luggage compartment so the effect would not be as impressive as a big block Chevy engine with a raised intake manifold, blower, and four-barrel Holley carburetor sticking out ..."

FCC Invites Comments on Eliminating
15 dB Gain Limit on Amateur Amps

FCC Invites Comments on Petition to Eliminate 15 dB Gain Limit on Amateur Amplifiers - RF CafeWell it's about time this antiquated rule was abolished! "Expert maintains that the 15 dB gain limitation is an unneeded holdover from the days when amplifiers were less efficient and the FCC was attempting to rein in the use of Amateur Service amplifiers by Citizens Band operators (aka CBers). While the FCC proposed in its 2004 Notice of Proposed Rulemaking and Order in WT Docket 04-140 to delete the requirement that amplifiers be designed to use a minimum of 50 W of drive power and subsequently did so, it did not further discuss the 15 dB gain limit in the subsequent Report. 'There is no technical or regulatory reason an amplifier capable of being driven to full legal output by even a fraction of a watt should not be available to Amateur Radio operators ..."

MACOM Sues Infineon Technologies
4G/LTE and 5G Semiconductors

MACOM Sues Infineon Technologies 4G/LTE and 5G Semiconductors - RF CafeMACOM Technology Solutions Holdings, a leading supplier of high-performance analog RF, microwave, millimeterwave and photonic semiconductor products, today announced that it has initiated legal action against Infineon Technologies and International Rectifier (acquired by Infineon in 2015), to defend its rights to use the pioneering and patented GaN technology developed by Nitronex (acquired by MACOM in 2014) in MACOM's core markets. GaN is a next-generation technology that promises to improve network data service and cell coverage of 4G/LTE and 5G basestations while reducing their energy consumption and associated carbon footprint ...

Single-Atom Magnet Breaks
New Ground for Data Storage

Single-Atom Magnet Breaks New Ground for Data Storage - RF Cafe"EPFL scientists have built a single-atom magnet that is the most stable to-date. The breakthrough paves the way for the scalable production of miniature magnetic storage devices. Magnetic storage devices such as computer hard drives or memory cards are widespread today. But as computer technology grows smaller, there is a need to also miniaturize data storage. This is epitomized by an effort to build magnets the size of a single atom. However, a magnet that small is very hard to keep 'magnetized,' which means that it would be unable to retain information for a meaningful ..."

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