九九视频热线视频精品15 -  By the time this Carl & Jerry episode entitled "Vox Elektronik" was published in 1958, creator and author John T. Frye had written the techno-dramas for Popular Electronics magazine for four years - beginning with the first edition of the publication in October 1954 ("A New Company Is Launched"). In this saga, the teenagers, both of whom already have shared many adventures involving homemade electronic gizmos and Ham radio, experience one of the instances of girl craziness competing for the attention of one or the other. It involves a Charlie McCarthy-style wooden dummy named "Splinter." Used in the story is a dummy-fide joke about onions and the River Kwai, no doubt a reference to the World War II movie "Bridge on the River Kwai*," which had hit the movie theaters about a year earlier...
 "The LeonardoOsprey MM AESA multi-mode surveillance radar is for helicopters, fixed-wing aircraft, and unmanned aerial vehicles (UAVs). Military unmanned aerial vehicle (UAV) experts at Northrop Grumman Corp. will upgrade a sophisticated surface-search radar system on as many as eight of the U.S. Navy's MQ-8C Fire Scout shipboard unmanned helicopters. Officials of the Naval Air Systems Command at Patuxent River Naval Air Station, Maryland, announced their intention Monday to award an order to the Northrop Grumman Aeronautics Systems segment in San Diego to provide as many as eight AN/ZPY-8 radar aircraft-kits (A-kits) for MQ-8C UAVs..."
 If you are reading this, then chances are you owe a part of your livelihood to three gentlemen by the names of Bardeen, Brattain and Shockley. On this day 73 years ago the trio announced their discovery of a gain producing semiconductor device that they dubbed a 'transistor' due to its dual nature as atransconductance amplifier and a variable resistance. This article by magazine editor Hugo Gernsback, in celebrating the 10-year anniversary of the transistor, mentions that somewhere in the neighborhood of 30 million of the little miracle components would be sold that year. The microprocessor in the device you are using to read this contains more than a billion. By comparison, the 'primitive' year-2000-vintage Intel Pentium 4 itself integrated more than the 30,000,000 transistors...
 Jack Browne has an interesting piece over on the Microwaves & RF website entitled, "Integrated Simulators Study EM Effects." He begins: "Electromagnetic simulators are gaining in power and ease of use but also becoming more available integrated into other high-frequency simulation software programs. Computer software simulators come in many varieties, tackling everything from passive circuit elements to full electronic systems. As a form of 'thread' that ties them together, electromagnetic (EM) simulators show the EM fields generated by devices, circuits, and systems. They may do it in planar or two-dimensional (2D) form or in three dimensions (3D), showing EM fields in all three axes. EM simulators are ever-evolving, providing increased insights into electronic designs. As part of this evolution..."
 Lemos International Technologies is both a designer and manufacturer of wireless products and a distributor of products from other world-class manufacturers. A modular approach to wireless connectivity helps eliminate much of the technical design and testing and also simplifies or eliminates the need for expensive conformance testing and certification. Ready-to-use Bluetooth, GPS, Wi-Fi, licensed and unlicensed band products are available. Custom design services can help you achieve success with your project's unique needs.
 Radio-Craft magazine dedicated its January 1947 issue to the fortieth anniversary of Lee de Forest's invention of theAudion tube - the world's first successful controllable electrical signal amplifying device. Many articles are presented that were written by people who knew de Forest personally (including editor Hugo Gernsback) and followed his progress and/or actually worked with de Forest during his experiments. This particular "Birth of the Audion" piece was by Frank E. Butler, who provides "A first-hand account written by an assistant of de Forest throughout the hard years which immediately preceded the most revolutionary invention in all the history of radio." If you have never read an account of the evolution of the Audion, you need to read this. It is akin to the path Thomas Edison took when working to perfect his incandescent light bulb. When you have no prior work to draw upon, success often requires tiresome repetition...
 "A space-based, virtuallyunhackable quantum Internet may be one step closer to reality due to satellite experiments that linked ground stations more than 1,000 kilometers apart, a new study finds. Quantum physics makes a strange effect known as entanglement possible. Essentially, two or more particles such as photons that get linked or 'entangled' can influence each other simultaneously no matter how far apart they are. Entanglement is an essential factor in the operations of quantum computers, the networks that would connect them, and the most sophisticated kinds of quantum cryptography, a theoretically unhackable means of securing information exchange. The maximum distance over which researchers have thus far generated quantum cryptography links between stations on Earth is roughly 144 kilometers..."
 The iconumerator (electronic particle counter), the vidicon tube (TV image recorder), the Electro Importing Co.'s Telimco (world's first home wireless outfit), the Wireless Association of America (founded before ARRL), the Dynamophone (voice-activated switch), the "Swatties" (members of the Society of Wireless Telegraph Engineers), the "Detectorium" (silicon crystal detector), Ralph 124C 41+ and his sweetheart Alice 212B 423 (Gernsback sci-fi series) were covered. Radio Amateur News predated QST as America's premier magazine for Hams, the famous 1919 "Verboten" cartoon (protested limitations on private radio operators from the wartime era), the de Forest "Oscillion," Major Armstrong's superregenerative circuit, the first "network" broadcast (WEAF in New York City and WNAC in Boston), the Reinartz, the Super, the Autoplex, the Solo dyne, and the Neutrodyn (home radio receiver kits), Tec-Teleducation (audiovisual classrooms)...
 RF Cafe's raison d'être is and always has been to provide useful, quality content for engineers, technicians, engineering managers, students, and hobbyists. Part of that mission is offering to post applicablejob openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge. 3rd party recruiters and temp agencies are not included so as to assure a high quality of listings. Please read through the easy procedure to benefit from RF Cafe's high quality visitors...
 LadyBug Technologies was founded in 2004 by two microwave engineers with a passion for quality microwave test instrumentation. Our employees offer many years experience in the design and manufacture of the worlds best vector network analyzers, spectrum analyzers, power meters and associated components. The management team has additional experience in optical power testing, military radar and a variety of programming environments including LabVIEW, VEE and other languages often used in programmatic systems. Extensive experience in a broad spectrum of demanding measurement applications. You can be assured that our Power Sensors are designed, built, tested and calibrated without compromise.
 TheTriplett Electric Instrument Company has been in continuous operation since 1904, although today it goes by the name Triplett Test Equipment & Tools. It was founded in 1904 in Bluffton, Ohio, by Ray L. Triplett. Mr. Triplett is holding his company's first vacuum tube tester, the Readrite Model 201, which debuted in 1921, in this full-page advertisement that appeared in a 1954 issue of Radio & Television News magazine. Triplett claims it is the first commercial tube tester. A pretty extensive search did not turn up any photos of the Model 201 tube tester, but there is a follow-on Model 215 tube tester on Steven Johnson's Readrite & Triplett history webpage. Here, too, is a very informative page outlining Triplett's history, including a picture of the "portable" ammeter built into a pocket watch case. The "new" Model 3423 Mutual Conductance Tube Tester, priced at $199.50 in 1954, is the equivalent of $1,901.50 in today's money...
 ConductRF's latest innovation isHigh-Frequency RF Jumper Cables with 2.92 mm, 2.4 mm or 1.85 mm connectors as standard. This assemblies use our optimized direct solder attached connectors and our superior double shielded hi-frequency A61SW flexible cable with shielding effectiveness greater than -100 dB. These cables are design to support the latest requirements for 5G applications for cross connecting modules, but can equally be used in any field where hi-frequency jumper cables are required. Beyond our standard interconnect, we can also offer solutions with SMP, SMPM, SMA and many other common connector interfaces. Hi-Performance right angled options are available utilizing hard setting shrink tube to form the cable bend...
 "Establishing long-range tactical communications for U.S. troops in remote locations currently requires giant parabolic dishes, tall pole-mounted antennas, large antenna domes, and high-power amplifiers. Besides their significant weight, power, and cost (SWAP-C), these antennas present large visual and radio frequency (RF) signatures, are vulnerable to jamming, and constitute a single point of failure. To break this dependence on big antennas and amplifiers, DARPA recently announced theResilient Networked Distributed Mosaic Communications (RN DMC) program. RN DMC aims to provide long-range communications through 'mosaic' antennas composed of spatially distributed low SWaP-C transceiver elements or 'tiles.' This approach replaces high-powered amplifiers and large directional antennas with mosaics of dispersed tile transceivers. Transmit power is distributed among the tiles, and gain is achieved through signal..."
 Please take a few moments to visit theeverythingRF website to see how they can assist you with your project. everythingRF is a product discovery platform for RF and microwave products and services. They currently have 267,269 products from more than 1397 companies across 314 categories in their database and enable engineers to search for them using their customized parametric search tool. Amplifiers, test equipment, power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers, power supplies, and everything else. Please visit everythingRF today to see how they can help you.
 An ad for Cornell Dubilier's newUltra-Flat Aluminum Electrolytic Capacitors that appeared in Aerospace & Defense magazine caught my attention. Electrical energy density is a big topic these days with the need to cram extremely large amounts of charge storage into extremely small spaces. The future of electric-powered cars, airplanes, boats, motorcycles, portable tools and appliances, radios, phones, lights, computers, etc., depends on high density energy storage. Supercapacitors are being used in many applications in place of batteries, especially where cost, space, and an ability to be recycled (charged / discharged) thousands of times without loss of performance. Specs: 2 or 3 mm profile, high energy density of 0.4 J/cc, replaces banks of solid tantalum chips, 3000 hr life @85?C without voltage derating...
 When I read about Du Mont's Iconumerator, the first thing that came to mind was the video of the Rockwell Retro Encabulator and General Electric's Turboencabulator. As it turns out, the Du Mont device is real. This article from a 1955 issue of Radio Electronics discusses a new type of oscillator-amplifier that works on the principle ofmicrowave amplification by stimulated emission of radiation (maser). It used ammonia as a masing medium. Masers were quickly applied to commercial broadcast systems, to military communications systems, and in laboratories. The state of the art has of course advanced far beyond the relatively crude apparatus shown here, but it is always good to have a working knowledge of the technology's history...
 MPDevice (MPD) has become a trustworthy and reliable company in the global RF market as a manufacturer of passive RF Devices. Included are attenuators and terminations, coaxial connectors, adapters, and cable assemblies, DC blocks, surge arrestors, power combiner / dividers, and directional couplers. The Korean Telecommunication market is now entering into the era of hyperconnected society. With continuous enhancement in R&D capabilities and quality control, MPD will continue in an effort to become the No. 1 technologically innovative company with a focus on the emerging 5G marketplace.
 "The squeaky wheel gets the grease," is an old saw that has long been true when it comes to government policy, applying to common citizens and paid professional lobbyists alike when attempting to influence laws and regulations. Tactics range from letter writing, to peaceful town hall meetings and outdoor public gatherings, to court challenges, to large organized terrorist groups destroying property and livelihood (and often bodily harm). Some causes are unarguably righteous, peaceful and honest, while others use subversive methods to coerce policy makers into adopting their ideas. Such has been the case throughout history in all nations. Amateur radio operators have had a mostly amiable relationship with the Federal Communications Commission (FCC) since its inception in the early days of Marconi. However, due to the perceived needs (real and imagined) of wartime and commercial radio success, amateurs' privileges have been encroached upon numerous times, and it required the action of citizens to re-claim lost or prevent...
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