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Homepage Archive - May 2022 (page 2)

See Page 1 | 2 | 3 | 4 | 5 of the May 2022 homepage archives.

Friday the 13th

Grayburne TV-IF Signal Boosters

Grayburne TV-IF Signal Boosters, April 1952 Radio-Electronics - RF CafeAdd-on devices like this "TV-IF Signal Booster" began appearing in all sorts of magazines back in the early 1950s as television sets became more and more of a household fixture, and people were beginning to assume the now well-establish couch potato domestic class. According to this advertisement by Grayburne Corporation, "experience proves a 20% average boost in overall signal is all that's needed to give satisfactory reception." Since their signal booster plugs into the IF path, it is probably safe to assume the gain refers to voltage and not power. A 20% gain in voltage is 10 * log (1.2) = 0.79 dB, which is not much. Most likely the vast majority of TV installations would benefit much more from fine tuning of the antenna and transmission cable system, but to be fair, this devices targets indoor installations where the antenna is rabbit ears that came installed on the set. In that case, relocating the television to another place in the room and fiddling with the rabbit ears would also likely result in as much or more of an improvement as the booster...

Retentive GaN Non-Volatile Memory

Speedy, Durable Retentive GaN Non-Volatile Memory - RF Cafe"Hong Kong University of Science and Technology (HKUST) reports on a gallium nitride (GaN) non-volatile memory (NVM) with good speed, retention and endurance at the same time. In silicon-based NVMs there tends to be a trade-off in these characteristics, creating a manufacturing 'trilemma' due to the use of Fowler-Nordheim tunneling across a tunnel oxide (TO) to change the memory state. The researchers comment: 'This work shows that the mainstream GaN-on-Si platform can also accommodate high-performance non-volatile memory devices in addition to the power and radio frequency (RF) devices, to enable highly intelligent electronic systems.' The device integrated a p-channel field-effect transistor (p-FET) with p-i-n heterojunction diode. The p-FET consisted of aluminium oxide (Al2O3) gate insulator on p-GaN..."

Kennedy Superheterodyne Short-Wave Converter Radio Service Data Sheet

Kennedy Superheterodyne Short-Wave Converter Radio Service Data Sheet, April 1932 Radio-Craft - RF CafeThis Radio Service Data Sheet for the Kennedy Superheterodyne Short-Wave Converter (Model 54 "Globe Trotter") is an example of the dozens of similar schematic and alignment instruction sheets that have been posted on RF Cafe over the years. It appeared in a 1932 issue of Radio−Craft. Obtaining technical information on most things, even readily available items, prior to the Internet era was often very difficult - if not impossible. Service centers had what was need provided by manufacturers and distributors, but if you wanted to find a part number or service data on a refrigerator, radio, lawn mower, garage door opener, etc., and did not have the original paperwork, you were usually out of luck. Nowadays a Web search will quite often get you what you need thanks to people (like me) who go to the trouble of making the information available. The stuff doesn't just magically appear or get posted by benevolent governmental entities...

Senior Principal Engineer: TWT and HPA Design Needed by Raytheon

/2022/Senior-Principal-Engineer-TWT-HPA-Design-Raytheon-Missiles-Defense-5-10-2022.htm"> Senior Principal Engineer: TWT and HPA Design Needed by Raytheon Missiles & Defense - RF CafeAt Raytheon Missiles & Defense, you have the opportunity to try new things and make a bigger difference across a broader end-to-end solution, a richer technology and product set, an expanded range of disciplines, a growing global footprint and a more diverse team of colleagues and customers. Raytheon now has an opportunity for an experienced /2022/Senior-Principal-Engineer-TWT-HPA-Design-Raytheon-Missiles-Defense-5-10-2022.htm"> Senior Electrical Engineer: TWT & HPA Design who is seeking to utilize their strong academic background and experience in High Power/High Voltage Transmitters. This position requires an experienced senior technical and business leader with a proven track record of invention, capture, and successful execution in High Power Microwave (HPM) and Pulsed Power technologies. Responsibilities include design and hands-on testing of high voltage/high power RF components plus providing technical support to production activities across multiple programs. Team leadership skills including cost and schedule management plus proposal writing and presentation experience are desired...

National Company Advertisement: Modulation

National Company: Modulation, October 1947 QST - RF Cafe"It is anybody's guess as to what modulation system the amateur of 1975 will be using." That forward-looking line appeared in this 1947 QST magazine infomercial by the National Company. The writers probably had no real idea how different electronics would be 25 years in the future, especially since John Bardeen et al would not invent the transistor until two more months (December 1947) after the publication of this issue. In their traditional style, this full-page advertisement was heavy on text and light on images. The company invested in customer education with the hope being a well-informed and appreciative hobbyist would reward them with patronage...

RF & Electronics Symbols for Visio

RF Electronics Wireless Analog Block Diagrams Symbols Shapes for Visio - RF CafeWith more than 1000 custom-built symbols, this has got to be the most comprehensive set of Visio Symbols available for RF, analog, and digital system and schematic drawings! Every object has been built to fit proportionally on the provided A-, B- and C-size drawing page templates (or can use your own). Symbols are provided for equipment racks and test equipment, system block diagrams, conceptual drawings, and schematics. Unlike previous versions, these are NOT Stencils, but instead are all contained on tabbed pages within a single Visio document. That puts everything in front of you in its full glory. Just copy and paste what you need on your drawing. The file format is XML so everything plays nicely with Visio 2013 and later...

Many Thanks to Centric RF for Their Continued Support!

Centric RF microwave components - RF CafeCentric RF is a company offering from stock various RF and Microwave coaxial components, including attenuators, adapters, cable assemblies, terminations, power dividers, and more. We believe in offering high performance parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz at power levels from 0.5-500 watts are available off the shelf. Order today, ship today! Centric RF is currently looking for vendors to partner with them. Please visit Centric RF today.

Thursday the 12th

Bell Telephone Labs - Electron Beams

Bell Telephone Laboratories - Electron Beams, April 1952 Radio-Electronics - RF CafeThere is a physical limit to how small of a distance may separate two distinct objects (line, dots, etc.), generally agreed to be about half a wavelength of the color being observed, and be seen with perfect human eye. Applying that rule of thumb to blue light with a wavelength of approximately 4000 Å (400 nm) yields a distance of 200 nm. Accordingly, there is no amount of magnification possible which will allow a healthy human eye to resolve objects closer together than that. Even with perfect optics, magnifications of greater than about 1500x are not able to render greater detail. To resolve smaller distance requires shorter wavelengths, but we cannot see them directly and need a device to transform the detected image into a visible image. That is what an electron microscope does to enable molecule sized particle to be "seen." The SARS-CoV-2 particle has been measured by electron microscopy and found to range between 50 to 140 nm, so it cannot be viewed directly with an optical microscope. Cigarette smoke is about 400 nm in diameter...

Printable Logic Circuits from Self-Assembled Protein Complexes

Printable Logic Circuits from Self-Assembled Protein Complexes - RF Cafe"This paper describes the fabrication of digital logic circuits comprising resistors and diodes made from protein complexes and wired together using printed liquid metal electrodes. These resistors and diodes exhibit temperature-independent charge-transport over a distance of approximately 10 nm and require no encapsulation or special handling. The function of the protein complexes is determined entirely by self-assembly. When induced to self-assembly into anisotropic monolayers, the collective action of the aligned dipole moments increases the electrical conductivity of the ensemble in one direction and decreases it in the other. When induced to self-assemble into isotropic monolayers, the dipole moments are randomized and the electrical conductivity is approximately equal in both directions. We demonstrate the robustness and utility of these all-protein logic circuits by constructing pulse modulators based on AND and OR logic gates that function nearly identically to simulated circuits. These results show that digital circuits with useful functionality can be derived from readily obtainable biomolecules using simple, straightforward fabrication techniques that exploit molecular..."

All Elements Heavier Than Helium Are Metals?

All Elements Heavier Than Helium Are Metals? - RF CafeAstronomers consider all elements heavier than helium to be metals. That definition obviously does not jive with the standard chemical definition of a metal as an element that readily conducts electricity, but a concept called "metallicity" argues that from a star (and therefore the universe) formation perspective, extremely high temperatures and pressures in first generation stars (like our sun) preclude the identification of distinct elements other than hydrogen and helium. Heavier elements, such as lithium (#3 on the periodic chart and a major component in LiIon batteries, is classified as a metal in chemistry) are overwhelmingly created after a massive enough hydrogen star collapses and begins fusing H and He into heavier elements. The relative abundance of hydrogen in the universe is deemed to be about 92%, and helium is 7.1%, so together they comprise about 99% of all elements. Universally, oxygen is at 0.1%, carbon is 0.06%, nitrogen is 0.015%, silicon is 0.006%, and iron is 0.004%. By comparison, the Earth's elemental composition is 48.8% oxygen, 14.3% iron, 13.8% silicon, 0.2% hydrogen...

RF Electronics/CCA Design Sr. Principal Engineer Needed by Raytheon

/2022/RF-Electronics-CCA-Design-Sr-Principal-Engineer-Raytheon-Missiles-Defense-5-10-2022.htm"> RF Electronics / CCA Design - Sr. Principal Electrical Engineer Needed by Raytheon Missiles & Defense - RF CafeAt Raytheon Missiles & Defense, you have the opportunity to try new things and make a bigger difference across a broader end-to-end solution, a richer technology and product set, an expanded range of disciplines, a growing global footprint and a more diverse team of colleagues and customers. Raytheon Missiles and Defense is seeking an engineering professional to work with a variety of programs as a contributor to detailed design, simulation, product development, and initial product testing. The RF Products Department is currently searching for /2022/RF-Electronics-CCA-Design-Sr-Principal-Engineer-Raytheon-Missiles-Defense-5-10-2022.htm"> Electrical Engineers who have experience designing RF and Microwave hardware & CCA design, including transmitters, receivers, and exciters. This role includes design and test activities that span preliminary design to integration. Products we develop support radar and datalink applications on a variety of tactical missile programs. Critical to this role will be designing for challenging mechanical constraints and extreme environments...

Pilotless Plane Run by Radio

Pilotless Plane Run by Radio, May 1946 Radio News - RF CafeNews reports are full of features about the wave of radio controlled (R/C) "drones" terrorizing citizens with their often inexperienced pilots navigating their camera-laden craft to peer into bedroom windows, obtain "birds-eye" views of sporting events, and to be a general pain in the posterior to people trying to enjoy their right to privacy and safety (except, of course, unless it is the Government choosing to violate them). Incredible advances in radio, navigation, and sensor systems has facilitated a wide variety of very affordable multirotor (the correct term, not "drone") aircraft that can literally fly themselves. For under $500 you can buy a GPS-guided multirotor that can be programmed to fly to one or more waypoints and return to the launch location, with range and flight duration limited only by battery capacity. Gimbaled, remotely steerable cameras can snap photos or record video and either store it onboard for later retrieval or wirelessly transmit the images back to the operator. Platform stabilization is provided by ultra-miniature, ultra-lightweight orientation and rate gyros...

RF Cafe Quiz #33: Battlespace Technologies

RF Cafe Quiz #33: Battlespace Technologies: Network-Enabled Information Dominance - RF CafeThis quiz is based on the information presented in Battlespace Technologies: Network-Enabled Information Dominance, by Richard S. Deakin. Published by Artech House. Note: Some of these books are available as prizes in the monthly RF Cafe Giveaway. This book has some of the best photos of modern war-fighting technology that I have seen. "The era of mechanized warfare is rapidly giving way to the battle for information superiority enabled by electronic technologies that provide data for detailed analysis of enemy forces and capabilities. this book discusses how to use sensor technologies, including radar and electronic warfare systems, to disseminate information to key decision makers in timely and relevant manner..."

RF & Electronics Stencils for Visio

RF & Electronics stencils for Visio r4 - RF CafeWith more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1 scale so that measurements can be made directly using Visio built-in dimensioning objects. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...

Many Thanks to ConductRF for Continued Support!

ConductRF coaxial cables & connectors - RF CafeConductRF is continually innovating and developing new and improved solutions for RF Interconnect needs. See the latest TESTeCON RF Test Cables for labs. ConductRF makes production and test coax cable assemblies for amplitude and phased matched VNA applications as well as standard & precision RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the iBwave component library. They also provide custom coax solutions for applications where some standard just won't do. A partnership with Newark assures fast, reliable access. Please visit ConductRF today to see how they can help your project! 

Wednesday the 11th

The "Best Teacher"

The "Best Teacher", March 1954 Radio-Electronics - RF CafeWhen beginning to read this 1954 Radio-Electronics magazine article, I almost missed the uniqueness of the author's name: Henry Farad. Usually something like that appears in an April edition, but this being March, I figured it was just a clever device used by whomever really wrote the story. For anyone trying to enter the field of electronics repair in that era, reading this piece must have been discouraging, and Mr. Farad makes that clear up front by stating, "He is up against a problem as old as civilization - he hasn't been able to find a job because he has no experience; he can't get any experience because he can't find a job!" Profit margins were very low in repair work due to the usually undeserved reputation of service shops as being rip-off joints. Taking on an apprentice was a luxury few could afford since the payoff would take so long. Radio, TV, record players, etc., were not generally serviceable by laymen (except for swapping out vacuum tubes), and the throw-away mindset was not yet possible because of how relatively expensive those sets were. Accordingly, you might think knowledgeable servicemen...

Guidance Electronics Sr. RF Subsystem Engineer Needed by Raytheon

/2022/Guidance-Electronics-Senior-RF-Subsystem-Engineer-Raytheon-Missiles-Defense-5-10-2022.htm"> Guidance Electronics Senior RF Subsystem Engineer Needed by Raytheon Missiles & Defense - RF CafeAt Raytheon Missiles & Defense, you have the opportunity to try new things and make a bigger difference across a broader end-to-end solution, a richer technology and product set, an expanded range of disciplines, a growing global footprint and a more diverse team of colleagues and customers. Job Summary: Raytheon Missiles & Defense miniaturized guided weapons – rockets, artillery, GPS-guided mortars, radar-seeking and anti-armor weapons. (Raytheon image) "High-tech guidance systems are fitting into increasingly smaller weapons as engineers work to bring them the same pinpoint accuracy once found only in mammoth missiles and hulking bombs." The /2022/Guidance-Electronics-Senior-RF-Subsystem-Engineer-Raytheon-Missiles-Defense-5-10-2022.htm"> Guidance Electronics Team provides Electrical Systems Engineering to develop Guidance Electronics solutions for products across the Raytheon Missiles and Defense (RMD) portfolio. Our team develops missile Guidance Electronics Hardware. Our core electrical engineering responsibilities include architecture, analysis, requirements, integration, and test. Our core electrical engineering technologies include RF/RADAR, Navigation/IMU/GPS, Digital, and Power...

Parallel Resistance Chart

Parallel Resistance Chart, October 1958 Radio-Electronics - RF CafeIf you have ever placed a fixed resistor in parallel with a potentiometer to reduce the total resistance, then you are familiar with how you also convert a linear relationship of the wiper movement with resistance to one that is nonlinear. That is because the equation changes from Rtotal = Rx:potentiometer (where x is the potentiometer position) to Rtotal = (Rx:potentiometer * Rparallel) / (Rx:potentiometer + Rparallel). The graph of it looks like one of the curves in this chart. Since the total parallel resistance is always smaller than the lowest value of the two resistances, the greater the ratio of the two is, the more dominant the smaller resistance value becomes. That means as the potentiometer wiper approaches the minimum resistance end of its travel, the parallel resistor attached across it has virtually no effect. Since parallel-connected inductors and series-connected capacitors scale in the same manner as parallel-connected resistors, this chart is useful for those circuits as well. Series-connected resistors and inductors, and parallel-connected capacitors are simply the sums of their individual values...

Triad's HP Radio Uses Mg Alloy for UAV SWaP Requirements

Triad's High Power Radio Uses Magnesium Alloy to Meet UAV SWaP Requirements - RF CafeTriad RF Systems has secured a seven-figure design and production order from a prominent South Asian aerospace and defense company for the THPR1039, Triad's new, DTC-based, high power radio system designed for use in Group 2 UAS. The THPR1039 is a 10 W (5 W per channel), L-Band, dual MIMO radio that is used for long distance UAS Video and C2 links, which achieves RF link ranges in excess of 50km when used in both the ground and air radio segments. This unit is an expansion of Triads High Power Radio System (THPR) product line. It combines a DTC Solo8 MIMO radio, high power amplification, and custom filtering into a single, easy to integrate package. Group 2 UAS require the lightest payloads possible to maximize their flight endurance and mission duration. For this aircraft, Triad was given a directive to minimize the weight of the radio system. Triad's engineering met this challenge by designing the THPR1039's housing from magnesium alloy, instead of the aluminum alloys traditionally used for housing RF systems...

Mac's Radio Service Shop: A Little Lightning

Mac's Radio Service Shop: A Little Lightning, July 1948 Radio News - RF CafeBenjamin Franklin is famous for his kite-flying experiment whereby he "discovered" not electricity (as many people believe), but that lightning is a form of electricity (most people thought it was a jet of gas). A lesser known fact about Mr. Franklin is that he invented the lightning rod after realizing the electrical nature of lightning. His understanding of electric fields facilitated an implementation whereby hefty iron cabling interconnected a tall, pointed rod installed at the tallest point on a building and a spike driven into the ground. Lightning typically strikes the object that is the shortest distance (in terms of electrical field strength) from it because the discharge can begin at the lowest voltage. The presence of the grounded lightning rod above the highest point on a structure effectively brings that point all the way down to ground level, rendering it no longer as electrically tall, thereby reducing its likelihood of being struck by lightning. Contrary to common belief, the purpose of a lightning rod is NOT to attract lightning and provide a discharge path for the bolt. Benjamin (he insists I call him "Ben") was a hero in Philadelphia where his invention almost totally stopped the rash of fires that occurred all around the city whenever a major lightning storm occurred...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. Chances are you have never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed. An intro video takes you through the main features...

Thanks to Copper Mountain Technologies for Continued Support

Copper Mountain TechnologiesCopper Mountain Technologies develops innovative and robust RF test and measurement solutions for engineers all over the world. Copper Mountain's extensive line of unique form factor Vector Network Analyzers include an RF measurement module and a software application which runs on any Windows PC, laptop or tablet, connecting to the measurement hardware via USB interface. The result is a lower cost, faster, more effective test process that fits into the modern workspace in lab, production, field and secure testing environments.

Tuesday the 10th

Electrical Production Support Engineer Needed by Raytheon

/2022/Electrical-Production-Support-Engineer-Raytheon-Missiles-Defense-5-10-2022.htm"> Electrical Production Support Engineer Needed by Raytheon Missiles & Defense - RF CafeAt Raytheon Missiles & Defense, you have the opportunity to try new things and make a bigger difference across a broader end-to-end solution, a richer technology and product set, an expanded range of disciplines, a growing global footprint and a more diverse team of colleagues and customers. The /2022/Electrical-Production-Support-Engineer-Raytheon-Missiles-Defense-5-10-2022.htm"> Production Support Engineer is responsible for Circuit Card Assemblies (CCAs) and other electrical subsystems hardware. We are seeking candidates with the skills and passion to engineer complex systems, subsystems, circuit card assemblies and components. A successful candidate is one who can participate in a multi-disciplined team and properly apply engineering tools and processes. A candidate willing to collaborate and coordinate with Operations, Supply Chain, Quality, and other Engineering disciplines to resolve issues that may arise during production, testing, and integration. Qualified candidates must have experience with digital, analog and/or RF testing and experience debugging complex circuit card assemblies or electro-mechanical systems. Knowledge of RF / microwave devices preferred...

Radar on the Highway

Radar on the Highway, May 1956 Popular Electronics - RF CafeIn the opening scene of "Gladiators," Quintus remarks to Maximus (Russell Crowe), "A people should know when they've been conquered." Such truth is applicable to society today regarding ubiquitous surveillance. Less than decades ago the media was filled with stories of outrage over the discovery of some new form of monitoring and reporting system having been installed on highways, in shopping malls, along sidewalks, even bathrooms. Since the 9/11 terrorist attacks, anything goes with government snooping. Count the numbers of freedoms you have lost and the inconveniences suffered because of those 19 men with no identifiable common cause (wouldn't want to "profile"), 15 of which came from Saudi Arabia, and how they changed our lives forever. But, I digress. This story from 1956 shows how long stealth installation of radar speed traps have been in use. I was very surprised to see the detector disguised as a street lamp at such an early date...

New Method for Measuring Radio Antennas

U. of Arizona Researcher Develops New Method for Measuring Radio Antennas - RF Cafe"Joel Berkson, a third-year doctoral student at the University of Arizona James C. Wyant College of Optical Sciences and Steward Observatory, has developed a new way for precisely measuring the surfaces of radio antennas, which are used to collect and focus radio waves for astronomy and satellite communications. These dish-shaped antennas, like the ones depicted in the 1997 movie 'Contact' starring Jodie Foster, must be manufactured with an extremely high level of accuracy to work well. To ensure their accuracy, engineers measure the antenna surfaces using metrology, a technique that applies the science of measurement to manufacturing, instrumentation and calibration processes. 'People always want to make larger, more accurate antennas for radio telescopes, and more of them..."

RF & Analog Company Name Change History Quiz

RF Cafe Quiz #67: RF & Analog Company Name Change HistoryThis RF & Analog Company Name Change History Quiz challenges your knowledge of the history of familiar electronics products companies' name changes (aka etymology). Many of you have lived through the plethora of acquisitions, mergers, and name changes represented here. There might be more than one correct answer. You might need a motion sickness pill when navigating all the changes. Wikipedia is used as the reference because I know the historical information presented there is accurate (enough)...

Thanks to TotalTemp Technologies for Continued Support!

TotalTemp Technologies - RF CafeTotalTemp Technologies has more than 40 years of combined experience providing thermal platforms. Thermal Platforms are available to provide temperatures between −100°C and +200°C for cryogenic cooling, recirculating circulating coolers, temperature chambers and temperature controllers, thermal range safety controllers, space simulation chambers, hybrid benchtop chambers, custom systems and platforms. Manual and automated configurations for laboratory and production environments. Please contact TotalTemp Technologies today to learn how they can help your project.

Trameto Secures Second Round Funding

Trameto Secures Second Round Funding from Development Bank of Wales and u-blox AG - RF CafeTrameto, the innovator of smarter energy harvesting power management ICs (EH PMIC), announced today it has successfully closed the second round of seed funding with investment partners the Development Bank of Wales and u-blox AG (SIX:UBXN), a leading global provider of positioning and wireless communication technologies and services. Development Bank of Wales is an existing equity investor and board observer, and u-blox AG will also join the board as an observer. Commenting on the investment, Huw Davies, CEO and co-founder, says, "This funding round enables us to embark on the next part of our journey to engage more widely with the market to complete and promote our OptiJoule® energy harvesting PMIC solutions. Meeting the demand to remove or reduce the reliance on batteries used in wireless IoT devices is one of the initial application markets we are addressing. OptiJoule's harvester-agnostic and autonomous approach..."

The Neglected Current-Squared Galvanometer

The Neglected Current-Squared Galvanometer, February 1931 QST - RF CafeGalvanometers are the basis for most analog type meter movements - remember those things? They work by having the current flowing through a fine wire coil armature generate a magnetic field that displaces an attached needle. Most galvanometers respond nearly linearly to applied current, and therefore are used in voltmeters and ammeters with simple resistor series and parallel configurations. The current-squared galvanometer on the other hand, as reported in this 1931 issue of QST magazine, responds roughly linearly to power values. It can therefore be used in a transmitter output monitoring circuit, for instance, or within amplifier interstage coupling circuits to indicate peak coupling values while tuning. Yes, a linear ammeter could be used, but its needle deflection in terms of power would be nonlinear and could make obtaining fine adjustments readings difficult to discern...

Promote Your Company on RF Cafe for as Little as $40/Month

Sponsor RF Cafe for as Little as $40 per Month - RF CafeNew Scheme rotates all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000 website visits each weekday. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 12,000 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. If you need your company news to be seen, RF Cafe is the place to be.

Please Visit Triad RF Systems to Thank Them for Their Support

Triad RF SystemsTriad RF Systems designs and manufactures RF power amplifiers and systems. Triad RF Systems comprises three partners (hence 'Triad') with over 40 years of accumulated knowledge of what is required to design, manufacture, market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA, bi-directional, and frequency translating amplifiers are available, in formats including tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology partner than a vendor for our line-of-sight communications product line." Please check to see how they can help your project.

Monday the 9th

New Sound Recording System

New Sound Recording System, April 1952 Radio-Electronics - RF CafeJohn Potter Shields was somewhat of a prolific author of technical books, primarily on the subjects of electronics and amateur astronomy - both of which are interests of mine. This "New Sound Recoding System" article from a 1952 issue of Radio-Electronics magazine reported on a system he devised for writing audio to a photographic plate in a manner similar to a record engraving on a platter. He places an unexposed film plate in front of a cathode ray tube (CRT) and modulates the beam with audio, which is superimposed on a deflection plate signal that moves the beam (cathode ray) in a spiral of fine spacing from the outside edge of the CRT in toward the center - just like a record (both shellac* - the kind Moe would break over Curly's head - and vinyl). There is an amazing c1942 RCA video showing how shellac records were made. Note the nearly total absence of safety devices on machinery or on operators. I also notice an absence of visual inspection for surface flaws or contamination during the master production process...

X-Ray Tomography for Integrated Circuits

X-Ray Tomography for Integrated Circuits - RF Cafe"When you're baking a cake, it's hard to know when the inside is in the state you want it to be. The same is true - with much higher stakes - for microelectronic chips: How can engineers confirm that what's inside has truly met the intent of the designers? How can a semiconductor design company tell whether its intellectual property was stolen? Much more worrisome, how can anyone be sure a kill switch or some other hardware trojan hasn't been secretly inserted? Today, that probing is done by grinding away each of the chip's many layers and inspecting them using an electron microscope. It's slow going and, of course, destructive, making this approach hardly satisfactory for anybody ... [A]fter pondering this problem, we considered using X-rays to nondestructively image chips. You'd need to go beyond the resolution used in medical X-ray scanners. But it was clear to us that the needed resolution was possible. At that moment, what we've been calling the 'chip scan' project was born..."

Radio Circuit Page

Radio Circuit Page, October 1946 Radio News - RF CafeThese six schematics and parts lists were published in a 1946 issue of Radio News magazine. Included models are the Hoffman Model A300, the Emerson Model 505, the Olympic Models 6-501, 6-502, 6-503, the Radiola Models 61-5, 61-10, the Farnsworth Models ET-060, ET-061, ET-063, and the General Electric Model 321. All are tabletop models. Many, if not all, of these radios can be found on eBay eventually - maybe even right now. In fact, all of the thumbnail images shown below were just pulled from eBay listings...

Anatech Electronics Intros 3 Filter Models for May

Anatech Electronics Intros 3 Filter Models for May 2022 - RF CafeAnatech Electronics offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. Three new filter models have been introduced - a 912.5 MHz GSM cavity bandpass filter with N-type connectors, a 906-924 MHz surface mount ceramic duplexer, and a 120-1000 MHz highpass filter with SMA connectors. Custom RF power directional coupler designs can be designed and produced when a standard cannot be found, or the requirements are such that a custom approach is necessary...

National Company Infomercial

National Company Infomercial, May 1951 QST - RF CafeNational Company, headquartered in Malden, Massachusetts, was a manufacturer of radio receivers for military and amateur use in the mid part of last century. They ran many full-page advertisements that were actually infomercials in that much more of the content presented generally useful technical information than pitched a product. This particular installment, which appeared in a 1951 issue of QST magazine, describes how extensive experimentation and testing on their HRO-50 receiver by a Ham radio guy led to a circuit change in future production models. It involved adding a tuning stage to the band select filter. An equivalent scenario today would probably involve an algorithm change to the SDR (software-defined radio) software...

Post Your Engineer & Technician Job Openings on RF Cafe for Free

/jobs.htm" target="_top"> Engineering Job Board - RF CafeRF 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 /jobs.htm" target="_top">job 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...

Thanks Once Again to everythingRF for Long-Time Support!

everything RF Searchable Database - RF CafePlease take a few moments to visit the everythingRF 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.

Sunday the 8th

Ham Radio Theme Crossword Puzzle for May 8th

Amateur Radio Theme Crossword Puzzle for May 8th, 2022 - RF CafeThis May 8th custom made crossword puzzle has an Amateur Radio (aka Ham Radio) theme, compliments of RF Cafe. Clues specifically related to the Ham Radio theme are marked with an asterisk (*). All RF Cafe crossword puzzles are custom made by me, Kirt Blattenberger, and have only words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects. As always, this crossword puzzle contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort...

Get Your Custom-Designed RF Cafe Gear!

Custom-Designed RF-Themed Cups, T-Shirts, Mouse Pads, Clocks (Cafe Press) - RF CafeThis assortment of custom-designed themes by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins, Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's" design has been ripped off by other people and used on their products, so please be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢ per item - Cafe Press gets the rest of your purchase price. These would make excellent gifts for husbands, wives, kids, significant others, and for handing out at company events or as rewards for excellent service. It's a great way to help support RF Cafe. Thanks...

Many Thanks to LadyBug Technologies for Their Continued Support!

LadyBug Technologies RF Power Sensors - RF CafeLadyBug 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.

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page. About RF Cafe.

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RF Cascade Workbook 2018 by RF Cafe

Amplifier Solutions Corporation (ASC) - RF Cafe

Crane Aerospace Electronics Microwave Solutions: Space Qualified Passive Products