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Today in Science History

Tech Industry Headlines

Tech Industry Headlines - RF Cafe- Archive -

• Trump Replaces H-1B Visa Lottery w/Wage Bidding

• Pentagon Seeks Strategy to Spark Transform Data into Warfighting Tool

Ericsson Caught in Crosshairs Between China, Sweden

• ASA Partners with Nokia to Build 1st Moon-Based Cellular Network

Bulgaria Signs 5G Security Declaration with U.S.

FCC Extends Use of 4.9 GHz Band by Adopting New Rules

China's 5G Infrastructure Push Continues to Accelerate

U.S. Military to Hasten Adoption of 5G with Wireless Contracts

Timekeeping Theory Combines Quantum Clocks and Einstein's Relativity

Hughes Research and Development Laboratories

Hughes Research and Development Laboratories, October 1955 Radio & Television News - RF CafeWhen I saw this Hughes Research and Development Laboratories employment ad in a 1955 issue of Radio & Television News, I wasn't sure how to take it. The text of the ad makes no reference to the bar graph and the weird drawing. Note the "bottle" is actually a slide rule. The graph can be interpreted to indicate that the more education a person has, the less likely he is to have children. If the typical age of the respondent is in the twenties, then that might reflect how people still in school to earn a higher degree would not be having children. It might also show that people with higher degrees focus more on their careers than on having a family. If you extrapolate the graph backward, does it imply people with an Associate's degree might average 1.5 children, those with just a high school diploma have about 1.7 children, and high school dropouts average maybe 2.0 kids? You have to also assume that most of the people with higher degrees earned them prior to beginning work or else you would have to ask what the Ph.D. with 0.9 kids did...

Power Equivalent in the Electricity-Water Analogy

Power Equivalent in the Electricity-Water Analogy, Kirt's Cogitations #321 - RF CafeHave I mentioned that my YL, Melanie, decided she would earn her Amateur radio Technician license? After living in a household with a bilingual husband (English and Electronics) for nearly 38 years and having become fairly proficient at ETL (electronics as a third language*), Melanie decided to earn her Technician license. She has never delved into the technical aspects of electricity / electronics, but because of hearing me speak of it (too) often and having proof-read my writings and scanned and OCR'ed more than a thousand articles from vintage electronics magazines, her gray cells are permeated with the vocabulary, lingo, jargon, vernacular, slang, and argot of the realm. Being an expert test taker, she will undoubtedly pass the written test with flying colors. With much self-restraint, I have avoided offering my sage advice and knowledge during her studies of the ARRL's Ham Radio License Manual. The current edition is the 4th, being valid from 2018 through 2022. Melanie has asked for a little clarification on SWR, decibels and couple other minor topics, but otherwise has progressed...

Radio Telescopes Are Hollywood's Biggest Stars

Radio Telescopes Are Hollywood's Biggest Stars - RF Cafe"It's amazing how many iconic and forgotten radio telescopes pop-up in movies, TV shows, and documentaries. The human eye was our first space image detector. On a beautifully clear night at the Aoraki Mackenzie International Dark Sky Reserve in New Zealand with the Milky Way displayed above us, we can see about 5,000 stars. But to really see - that is, to detect and communicate into space - a radio telescope is needed. Such devices can receive radio waves from astronomical sources in the sky and are the main observing instrument used in radio astronomy. Whereas optical telescopes study the light wave portion of the spectrum, radio telescopes focus on the radio frequency portion of the electromagnetic (EM) spectrum emitted by almost all astronomical objects..."

Carl & Jerry: Two Detectors

Carl & Jerry: Two Detectors, February 1955 Popular Electronics - RF CafeListen to the Podcast! Just in time for Halloween, John T. Frye's teenage sleuths Carl & Jerry unexpectedly recorded a late-night conversation between two men where they plot how to dispose of the "body" when death occurred as a result of prolonged choking. Employing their trademark technical prowess and scheming ability, the pair sets a trap for the perpetrators and dutifully summon the authorities as they complete their nefarious act of the night before. Halloween comes into play because the recordings were made for use in creating sound effects during the reading of Edgar Allen Poe's "The Pit and the Pendulum" and "The Cask of Amontillado." This story, which appeared in a 1955 issue of Popular Electronics magazine, is a little dark compared to a typical story...

RIGOL Vector Network Analyzer App Note

Rigol Vector Network Analyzer App Note - RF CafeRIGOL has published a downloadable app note entitled "Advanced Measurements with a Vector Network Analyzer." It begins: "In our wireless world the need of RF component testing is one of a key factors to bring a product to market. Devices are getting smaller and are containing more and more complex components. It is a must to have knowledge of complex impedance (or admittance) and reflection / transmission parameters to bring the most optimum functionality to the RF device. RF components like filters, resonators, etc. can be calculated according to capacitance and inductive values. Software simulators can take these values and help fine tune the design. But at the end of the day, the quality and performance needs to be measured..."

Bittele Launches Fast and Easy Online Ordering Service

Bittele Electronics Launches Fast and Easy Online Ordering Service - RF CafeBittele Electronics, a Toronto-based Turn-key PCB Assembly firm specializing in prototype and low-to-mid volume printed circuit board (PCB) manufacturing and assembly, announced today the release of its Online Ordering Service featuring Live Chat and Zoom meeting support. This new, state-of-the-art tool allows customers to complete turnkey PCB assembly orders faster and with up to 25% price discounts. Bittele's Online Ordering Service enables a customer to complete all steps to complete a PCB Fabrication and Assembly order in under 20 minutes while qualifying for exclusive discounts that are automatically applied to the order. Once an online order is placed, it will be immediately processed and released to Bittele's production team...

Many Thanks to MPDevice for Continuing Support!

MPDevice - RF CafeMPDevice (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.

Hi-Fi Quiz

Hi-Fi Quiz, October 1955 Radio & Television News - RF CafeHere is a quick Hi−Fi Quiz for all you audiophiles out there. Although it appeared in a 1955 issue of Radio & Television News magazine, save for question #10 all of Q's and A's still apply to today's equipment. Even that one can be easily guessed. Q4 might seem a bit foreign, but think of the "groove" type as applying to 78, 45, or 33-1/3 rpm platters and you'll do OK. Question #7 could be a baffler (pun intended - you'll see how) were it not for one obviously invalid option that it takes an RF guy (or gal) to recognize its inanity. Good luck. BTW, I missed Q1, but should have known better.

Please Thank Res-Net Microwave for Their Long-Time Support!

Res-Net Microwave Components - RF CafeRes-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.

Do You Have an Engineering Failure Resume?

Do You Have an Engineering Failure Resume? - RF Cafe"Failure is an integral part of the engineering experience. It is so common that it has become an expectation and even affectionately referred to as Murphy's Law: 'Anything that can go wrong will go wrong.' It has been stated that the great American inventor Thomas Edison was once asked by a reporter how it felt to fail 700 times in the creation of the light bulb. His response: 'I have not failed 700 times. I have not failed once. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.' Henry Petroski, the famous American engineer specializing in failure analysis, wrote the following in his book, To Engineer Is Human: The Role of Failure in Successful Design: 'I believe that the concept of failure..."

Bell Telephone Laboratories Cavity Magnetron Development

Bell Telephone Laboratories Cavity Magnetron Development, October 1945 Radio News - RF CafeDevelopment of the cavity magnetron during World War II helped change the destiny of Allied forces through using high frequency radar with enough power to detect distant targets while using frequencies which were out of the normal detection bands of Axis forces' receivers. Most equipment at the time could not operate efficiently (or at all) above a few hundred MHz. It was considered a top-level secret with great concern that the technology not fall into the hands of German and Japanese scientists. According to this early post-war advertisement in a 1945 issue of Radio News, Bell Labs was totally consumed by the development of magnetrons, and was relieved to finally be able to boast of its critical role now that the war was over...

Please Welcome RIGOL as RF Cafe's Newest Supporter!

RIGOL Technologies (electronics test equipment)RIGOL Technologies is transforming the Test and Measurement Industry. Our premium line of products includes digital and mixed signal oscilloscopes, spectrum analyzers, function / arbitrary waveform generators, programmable power supplies and loads, digital multimeters, data acquisition systems, and application software. Our test solutions combine uncompromised product performance, quality, and advanced product features; all delivered at extremely attractive price points. This combination provides our customers with unprecedented value for their investment, reduces their overall cost of test, and helps speed time to completion of their designs or projects.

Times Microwave Systems ½" Plenum RF Cable for DAS Networks

Times Microwave Systems ½" Plenum RF Cable for DAS Networks - RF CafeTimes Microwave Systems, a pioneering brand in innovative RF and microwave interconnect assemblies, cables and connector design, announces the addition of a new 1/2" plenum RF cable to its product line. The LPA-500 LLPL air-dielectric corrugated plenum cable is a low-loss, plenum listed (type CMP) coaxial cable. Available now, its design offers excellent intermodulation performance, and can be used as feedlines within buildings to support distributed antenna systems (DAS); public safety communications systems; RF backbone interconnects within plenum airspaces; and additional applications. The LPA-500 LLPL is an affordable option that provides the quality and performance for which Times is universally recognized. The new 1/2" plenum RF cable...

Many Thanks to Withwave for Continued Support!

Withwave RF & Microwave Components - RF CafeWithwave manufactures an extensive line of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch, board edge, panel mount), calibration kits (SOLT), a fully automated 4-port vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures for calibration and multicoax cable assemblies. Frequency ranges from DC through 110 GHz. Please contact Withwave today to see how they can help your project succeed.

Housewives and Television

Housewives and Television, October 1947 Radio-Craft - RF CafeContrary to the scenario presented in this light-hearted mockery of housewives attempting to assemble some electronics kits, there were actually many women during the height of the radio and television age who were quite adept at handling soldering irons and test equipment. In fact, the case could be made that, given the 1947 appearance of this "Housewives and Television" piece in Radio-Craft magazine, women of the post-wartime industrial period were probably the most experienced and adept assemblers of electronics equipment. After all, it was Rosie the Riveter who built airplanes, ships, and tanks while Sally the Solderer built the bulk of the tens of thousands of radios, radars, sonars, medical and test instruments, vacuum tubes, amplifiers, and other electronics while the brothers...

Please Visit in Appreciation Reactel for Their Long-Time Support

Reactel Filters - RF Cafe

Reactel has become one of the industry leaders in the design and manufacture of RF and microwave filters, diplexers, and sub-assemblies. They offer the generally known tubular, LC, cavity, and waveguide designs, as well as state of the art high performance suspended substrate models. Through a continuous process of research and development, they have established a full line of filters of filters of all types - lowpass, highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact Reactel today to see how they might help your project.

Zeptoseconds: New Record in Short Time Measurement

Zeptoseconds: New Record in Short Time Measurement - RF Cafe"In 1999, the Egyptian chemist Ahmed Zewail received the Nobel Prize for measuring the speed at which molecules change their shape. He founded femtochemistry using ultrashort laser flashes: the formation and breakup of chemical bonds occurs in the realm of femtoseconds. Now, atomic physicists at Goethe University in Professor Reinhard Dörner's team have for the first time studied a process that is shorter than femtoseconds by magnitudes. They measured how long it takes for a photon to cross a hydrogen molecule: about 247 zeptoseconds for the average bond length of the molecule. This is the shortest timespan..."

Theory and Construction of Attenuators, Line Filters and Matching Transformers

The Theory and Construction of Attenuators, Line Filters and Matching Transformers, June 1932 Radio-Craft - RF CafeIt seems most of the articles we see on the subject of attenuator pads are based on signal reduction in terms of decibels for units of power. Although it is a simple matter to convert power decibels to voltage decibels, it would be more convenient if you are working with voltage to have formulas and tables of values based on voltage ratios. This article does just that. As a reminder, the decibel representation of a ratio is always 10 * log10 (x). If you have a voltage ratio of V1/V2 = 0.5, then 10 * log10 (0.5) = -3.01 dB. If you have a power ratio of P1/P2 = 0.5, then 10 * log10 (0.5) = -3.01 dB. Does that mean that -3.01 dB of voltage attenuation is the same as 3.01 dB of power attenuation? Confusingly, no. Let's say for the sake of simplicity that you have 1 V across a 1 Ω resistor...

Nokomis Looking for an RF/Electrical Mixed Signal Engineer

Nokomis Looking for an RF/Electrical Mixed Signal Engineer - RF CafeNokomis Inc., is a high technology research and development company located just south of Pittsburgh, PA. Nokomis does cutting-edge technology work for the Department of Defense (DoD) and other Government Agencies. We rank in the top 3 for entities under 300 employees in the state of Pennsylvania for the number of R&D contracts we typically win yearly. The candidate should be comfortable executing on and potentially leading multiple projects. This position requires a multi-disciplined Senior Electrical Engineer, capable of solving complex technical problems and providing innovative solutions in the areas of Electrical Engineering and the part, board and system level to develop the most sensitive Radio Frequency (RF) systems on the planet. Candidates with specialized experience in digital design, analog design mixed signal design or RF design will be considered as each of these disciplines is required. The ideal candidate will have an understanding of and experience with digital, analog, mixed signal and RF systems...

Many Thanks to Exodus Advanced Communications for Their Support

Exodus Advanced Communications - RF CafeExodus Advanced Communications is a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide. Power amplifiers ranging from 10 kHz to 51 GHz with various output power levels and noise figure ranges, we fully support custom designs and manufacturing requirements for both small and large volume levels. decades of combined experience in the RF field for numerous applications including military jamming, communications, radar, EMI/EMC and various commercial projects with all designing and manufacturing of our HPA, MPA, and LNA products in-house.

Electronics-Themed Comics, 1953 Radio-Electronics

Electronics-Themed Comics, November 1953 Radio-Electronics - RF CafeIt's about time for a little joviality so here are the three technology-themed comics which appeared in the November 1953 issue of Radio-Electronics magazine. They cover a wide range of situations experienced by electronics types back in the day, including the fickleness of customers, an exaggeration of an explorer's unexpected discovery deep in a jungle, and the frustrated indignation of a parts supplier by the selective memory of a serviceman in need of replacement components. Enjoy!

Windfreak Technologies withwave microwave devices - RF Cafe
Windfreak Technologies Axiom Test Equipment - RF Cafe
About RF Cafe
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Copyright: 1996 - 2024
    Kirt Blattenberger,

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while typing up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

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