Today in Science History -
 Just as most people no longer wear a wristwatch since their (practically) surgically attached smartphones can provide the time, few people bother with carrying around an electronic calculator. It's' been that way for at least a decade now. When this article entitled "Calculators Get Smaller, Smarter and Cheaper" appeared in a 1974 issue of Popular Mechanics magazine, pocket electronic calculators were still a relatively new phenomenon. Hewlett Packard had introduced their first calculator, the HP−35, just two years earlier. The first American-made pocket calculator, the Bowmar 910B, aka "The Brain," came out in late 1971/early 1972 and sold for about $240. It had only basic math functions and sported a tiny LED display. Prices fell very quickly as many companies were releasing models with more and more features. By the time of this article, calculators with basic functions could be bought for a mere $16.95 ($84.05 in 2019 money ...
 RF Cafe typically receives 8,000-15,000 website visits each weekday and about half that on weekends. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 7,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. I also re-broadcast homepage items on LinkedIn, Facebook, and Twitter. If you need your company news to be seen, RF Cafe is the place to be. Banner advertising begins at $175/month ...
 Triad RF, located in East Brunswick, NJ, is a leader in the design and manufacture of RF SSPAs and Systems. An Applications Engineer is needed to support our customers and provide them with pre-sales technical support on our products. Tasks include working with customers and recommending suitable products based on their radio link and system requirements. The applications engineer will also work with Sales Administrators and assist them in the preparation of customer quotes. The applications engineer will also work with the test lab in establishing design test standards based on customer requirements. Skills and qualification include: Understanding of basic electronics concepts such as NPN transistors, MOSFETS, TTL logic, supply voltage, current draw, power added efficiency, knowledge of amplifier-related concepts ...
 This is a repeat of something I posted a decade ago, but by now millions more people have entered the electronics realm and might appreciate it. You might, too, if you didn't see it originally. You have probably seen somewhere along the line in your electronics career the resistor cube problem. The 12 edges of the cube each contain a 1 Ω resistor, and the challenge is to calculate what the equivalent resistance is between two opposing corners. It is a daunting problem using straight circuit analysis, since it requires writing and solving multiple mesh equations. There are lots of opportunities for making mistakes. One option if you had the time and facilities would be to build the model in a circuit simulator and let it determine the result. Usually, though, the cube is thrust upon you in a compromising situation, like in a job interview ...
 "The latest International Amateur Radio Union Region 1 Monitoring System (IARUMS) newsletter reports the Russian "Contayner" over-the-horizon radar (OTHR) has been active in the 7, 10, 14, and 18 MHz amateur radio allocations (amateur radio is primary on 40, 20, and 17 meters). The OTHR transmissions have been 40 sweeps/second, FM on pulse, and 12 kHz wide. Additionally, IARUMS reports a significant increase in Russian military traffic using F1B, PSK, and orthogonal frequency division multiplex (OFDM) on 40, 30, 20, and 15 meters. IARUMS on November 13 reported an OTHR in northern Iran on 6.078 – 7.022 MHz, AM on pulse, 81 sweeps/second, 44 kHz wide."
 Axiom Test Equipment allows you to rent or buy test equipment, repair test equipment, or sell or trade test equipment. They are committed to providing superior customer service and high quality electronic test equipment. Axiom offers customers several practical, efficient, and cost effective solutions for their projects' TE needs and is committed to providing superior customer service and high quality electronic test equipment. For anyone seeking a way to offload surplus or obsolete equipment, they offer a trade-in program or they will buy the equipment from you. Some vintage items are available fully calibrated. Please check out Axiom Test Equipment today!
 The year was 1941 and the radio industry was going strong worldwide. Sales of receivers was hitting new highs every quarter and service shops had all the work they could handle for repair, upgrades, and installations. The radio broadcast realm was scrambling to build new studios, install transmitters and antennas, hire announcers and managers, and upgrade to keep up with the quickly evolving business. Take a look at these 24 full pages of radio-related products offered by the Sears, Roebuck Company in their Fall and Winter 1941-1942 catalog. It is typical of most radio manufacturers' catalogs of the era. For the last decade engineers had been working overtime to satisfy consumer demand for fancier cabinet designs with fancier features. So strong was public demand that people put their highest priority on acquiring the latest models (not unlike the smartphone craze of today). Then, ...
 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 applicable job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge (of course a gratuity will be graciously accepted). 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 ...
 The RCA Victor Model C9-4 is a 9-tube, 3-band superheterodyne console model radio made in the mid 1930s. A Radio Service Data Sheet for it appeared in the January 1936 issue of Radio-Craft magazine. The image of the radio was found on the RadioMuseum.org website. FM broadcasting was not in common use yet, so only AM bands and some shortwave bands were available. In fact, 1936 was the year that frequency modulation (FM) inventor Edwin H. Armstrong first demonstrated his newfangled concept that largely solved the electrical static noise problem cause by lightning, motor brushes, arcing overhead power lines ...
 This High Density Switched Reluctance Motor (HDSRM) designed by Newcastle University's Advanced Electric Machines (AEM) could be a serious game changer to the electric vehicle industry if it proves viable. The 6-phase motor does not use permanent magnets or copper conductors, and claims to be competitive in performance with the current crop of motors that need rare earth magnets and copper wire. That represents major advantages in lower cost and independence from rare earth magnets, which now come primarily from China. Be sure to watch the video. Jolly good show, chaps!
 ThinkRF Corporation, the leader in software-defined spectrum analysis, today announced the release of the PyRF3 Development Framework with support for version 3.0 of the Python Language Application Programming Interface (API). This latest API enables command, control and data acquisition using ThinkRF Real-Time Spectrum Analyzer platforms, including the ThinkRF R55x0 and R57x0 analyzers. The updated version ensures RF application developers can leverage the PyRF Development Framework to build custom solutions, integrate new capabilities, and develop or extend products quickly and easily. PyRF is a freely available, comprehensive development environment for wireless signal analysis, built on the Python Programming Language ...
 Res-Net Microwave has a complete line of precision RF & microwave components including attenuators, terminations, resistors, and diode detectors for commercial, military, and space applications. Products range from the small flange type to large 2,000 watt connectorized power attenuators and/or terminations at frequencies up to 26.5 GHz. In-house photo etch and laser trim capability. The company is a leader in development and production of the films required for these type of RF/microwave components. Please check out Res-Net Microwave's website to see how they can help with your current project.
 In 1958, most people were not accustomed to seeing the now-familiar maps plotting sinusoidal courses of satellites across the face of the earth. It had only been in October of the previous year that any object other than the moon was in orbit around our home planet - that was U.S.S.R.'s Sputnik. Just as people of all ages and all backgrounds enthusiastically joined in the newfangled phenomenon of aeroplanes after the Wright Brothers flew their fragile craft at Kitty Hawk, electronics communications and scientists worldwide hopped aboard the satellite train (so to speak). This article from a 1958 issue of Radio & TV News magazine provided insight into the construction and flight characteristics of early U.S. satellites, and offered advice on how to participate in the ongoing International Geophysical Year (IGY) research effort by tuning in and reporting your signal reception characteristics. Activity was not just the domain of operators with sophisticated equipment ...
 Sam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his November newsletter that features his short op−ed entitled "Is 5G Safe for Humans? No One Knows." The controversy over whether or not RF radiation from wireless devices - cellphones, notebook computers, tablets, smart meters, et al, is harmful to human body cells has been with us since the early 1990s, when the Wireless Revolution began. Industry standards groups have defined Specific Absorption Rate (SAR) levels for exposure that model human anatomy and cell structure in order to scientifically assess the effects of RF radiation. As with studies done with other controversial topics like tobacco and pharmaceuticals, the "truth" is as much subjective as it is objective, and the two side of the argument will never agree ...
 This quiz from Popular Electronics magazine challenges (not too much, though) your knowledge of energy conversion in common devices. A few of them might be unfamiliar to people born after about 1990, but even so, you've probably seem them all at some point, especially if you are a regular RF Cafe visitor (meaning you're probably smart). It won't be giving anything away by telling you that item B is a heater that screws into a light bulb socket, and item F is a phonograph stylus Robert P. Balin constructed many quizzes of this kind in the 1960s and 70s. A complete list of all the Popular Electronics Quizzes is lower on this page ...
 Axiom Test Equipment, an electronic test equipment rentals and sales company headquartered in San Diego, has published a blog post entitled "Turn on the Temperature with Thermal Test Systems," explaining the need to properly evaluate product function across the full range of expected ambient temperature conditions. Doing so helps guarantee favorable customer experiences and online ratings, as well as reduces costs of warranty service. It begins: "Electronic device performance is sensitive to temperature, with most electronic devices and components specified according to operating and storage temperature ranges. Those ranges differ according to the type of component and application, with electronic products for industrial and military applications usually ..."
 "Electromagnetic interference (EMI) can plague bus bars just like it does with cables. Here are the answers to some common questions. Do bus bars need EMI filters? Yes, they do. Just because they’re large imposing structures, they can cause interference in other systems if you don't measure the EMI and take steps to get it under legal limits. In some cases, you might want to reduce EMI even further than the legal requirement to make a quiet electrical environment for your sensors or control system. EMI noise is created by any fast-changing currents, often represented by the calculus term di/dt, that is, the change of current over time. Fast-changing currents have high di/dt. If those currents ..."
 Since 1961, MECA Electronics has designed and manufactured an extensive line of RF & microwave components for in-building, satellite, radar, radio, telemetry, mobile radio, aviation & ATC. Attenuators, directional & hybrid couplers, isolators & circulators, power dividers & combiners, loads, DC blocks, bias-Ts and adapters & cables. MECA has long been the 'backbone' of high performance wired and air-interfaced networks such as in-building applications, satellite communications, radar, radio communications, telemetry applications, mobile radio, aviation & air traffic communications.  Proving once again what a visionary Hugo Gernsback was regarding science and engineering, he published in his Radio-Craft magazine this prognostication for the eventual supplanting of point-to-point wiring with printed circuit boards. Admittedly, by 1948 the electronics industry had begun to outgrow hand-wired chassis assemblies with a rats nest of wires, components, and terminal strips. It was in dire need of a new paradigm that reduced labor costs and reduced the opportunity for wiring errors. Less than a year earlier (December 1947) the trio of engineers at Bell Labs announced their transistor invention, so Mr. Gernsback knew the world was about to change significantly. Bulky transformers, vacuum tubes, and high voltage circuits would soon be relegated - at least in the consumer product realm - to the newfangled television products, so miniaturization would follow quickly. Even the smaller fingers of women on the assembly lines ...
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