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Homepage Archive - March 2023 (page 2)

See Page 1 | 2 | 3 | 4 | of the March 2023 homepage archives.

Tuesday the 14th

Citizens Band (CB) Radio 10-Codes

Citizens Band (CB) Radio 10-Codes - RF CafeThe origin of the "10 codes" used in Citizens Band (CB) radio communications is not entirely clear, and there are several theories about their development. One theory suggests that the codes were developed by the Illinois State Police in the 1930s to enable faster and clearer communication over radio channels. Another theory suggests that the codes were developed by the United States Army Signal Corps during World War II. Regardless of their origin, the codes became widely used by CB radio operators in the 1960s and 1970s. They were popularized in part by the 1975 movie "Smokey and the Bandit," which featured the use of CB radio and the 10-4 code ("message received"). C.W. McCall helped popularized CB radio with his "Convoy" song in 1975. This list of "10-Codes" came from my copy of a Radio Shack book titled, "All About CB Two-Way Radio..."

Human Body Model ESD Testing

Human Body Model ESD Testing - RF CafeAs semiconductor device gate regions have shrunk in size, vulnerability to electrostatic discharge (ESD) has increased. The issue came to the forefront of the telecommunications industry's concerns during the early days of the cellphone era (late 1990's / early 2000's). While working at RFMD, I did quite a bit of  ESD experimenting as part of their efforts to develop GaAs PA's with a high level of ESD tolerance. Both human body model (HBM) and machinehand metal model (HMM) test were done. Huge advances in ESD protection has been made throughout the electronics industry. This short article from In Compliance magazine introduces the concept of ESD testing requirements, procedures, and test equipment...

Many Thanks to Berkeley Nucleonics for Continued Support!

Berkeley Nucleonics Corp - RF CafeBerkeley Nucleonics Corporation (BNC) is a leading manufacturer of precision electronic instrumentation for test, measurement, and nuclear research. Founded in 1963, BNC initially developed custom pulse generators. We became known for meeting the most stringent requirements for high precision and stability, and for producing instruments of unsurpassed reliability and performance. We continue to maintain a leadership position as a developer of custom pulse, signal, light, and function generators. Our designs incorporate the latest innovations in software and hardware engineering, surface mount production, and automated testing procedures.

Gold & Aluminum Bond Wire Properties

Gold Aluminum Bond Wire Properties (Archimedes Channel) - RF CafeGold wire bonding is a popular technique in the integrated circuit (IC) industry due to its reliability, durability, and low resistance. The technique is commonly used to create interconnects between components such as transistors, capacitors, and resistors, as well as to connect ICs to their packaging. See table of bonding wire properties below. Thermosonic Wire Bonding is a process used in the manufacturing of integrated circuits (ICs) to create interconnections between the different components of the IC. This technique involves the use of heat and ultrasonic vibrations to bond a thin wire made of gold or aluminum to the components of the IC. The process of thermosonic wire bonding typically involves several steps. First, a thin wire is fed through a machine that guides it to the correct location on the IC. The wire is then heated using a combination of high-frequency ultrasonic vibrations and thermal energy, which softens the wire and causes it to bond to the components of the IC. One of the advantages of thermosonic wire bonding is that it can create very strong and reliable bonds between the wire and the components of the IC. This is because the ultrasonic vibrations used in the bonding process help to break down any oxides or contaminants on the surface of the components...

Phase Shifter Reduces Signal Loss in Antennas

Phase Shifter Reduces Signal Loss in Antennas - RF Cafe"Researchers led by Dr Yi Wang from Birmingham's School of Engineering created the new type of high-performance phase shifter using a liquid Gallium alloy, which is said to vary the phase angle of microwave and millimetre-wave radio signals. The phase shifter is a key enabling technology for advanced phased array antennas (PAA) used in mobile base stations, satellites and radar systems. PAA systems use multiple phase shifters to provide the controlled phase increments that steer the radiation beam. However current phase shifters typically use semiconductors and suffer from high loss of signal and relatively poor power handling capability. In a statement, Dr. Wang said: 'An ideal phase shifter would provide a stable, and wide phase angle range with a minimal loss of signal over the operation bandwidth. However conventional phase shifters suffer from signal losses which increase as the phase angle increases, and the phase varies with frequency. Taken together, these issues can cause signal degradation and impair performance..."

Inside a 9-Volt Battery

Inside a 9-Volt Battery - RF CafeHave you ever wondered what is inside the familiar 9-volt battery (often referred to as a "transistor radio battery" in the last century)? I have read about there being AAAA cells (that's right, quadruple-A, A-A-A-A), but wanted to see for myself. So, I used a small screwdriver and a pair of pliers to remove the outer metal case. This first picture shows the six AAAA cells bundled together and contained with heat-shrink tubing. In the bottom photo, you can see that all six AAAA cells are connected in series. Each individual cell is 1.5 volts, so 6 x 1.5 = 9.0 volts. For a size comparison, a standard triple-A (AAA) cell is shown next to one of the AAAA cells. Here are the specifications for the Duracell Ultra 9V battery: Battery Capacity: 550 mAh Battery Technology: Alkaline (Single Use) Current: 2.1000 A Depth: 17.0 mm Height: 48.5 mm Width: 26.2mm Voltage: 9.00 V Weight: 44.0 g Since the cells are connected in series, than means the overall current rating for the battery assembly is the same for each AAAA cell. So, each AAAA cell is rated at 2.1 amps with an energy capacity of 550 mAh (milliamp-hours)...

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...

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 13th

Electronics-Themed Comics

Electronics-Themed Comics, February 1960 Radio-Electronics - RF CafeThree out of five of these electronics-themed comics are fire related. Maybe that was a common issue back in 1960 when they appeared in Radio-Electronics magazine, but it was probably just a coincidence. The page 39 comic has a topic common in the earlier days of television as can be seen in some of the others in the huge list of electronics- and technology-themed comics at the bottom the the page. Being a lifelong teetotaler, I can't really relate to the page 153 comic, but I'm guessing a lot of RF Cafe visitors can appreciate it...

Antenova GNSS Module w/Integrated Antenna

Antenova Ultra-Small GNSS Module w/Integrated Antenna - RF CafeAntenova Ltd, the UK-based manufacturer of antennas and RF antenna modules for M2M and the IoT, is to reveal its latest compact high precision GNSS module at Embedded World. The new product, GNSSNova M20072, is a GNSS receiver with integrated GNSS antenna and greatly reduced power consumption. M20072 uses a MediaTek 12 nm low energy chip with 1.8V power supply which uses 70% less power than older chipsets. The power consumption of the module can therefore be as low as 21 mW for a GPS fitness tracker, and GNSS-enabled products built with the M20072 will have a longer battery life. Antenova created this ready-made receiver solution for easy integration into a design. The module contains an integrated omni-directional GNSS antenna, on-board LNA and a SAW filter which work together to boost the signal to the GNSS processor if line-of-sight to the horizon is difficult...

Microwave Plumbing Replaces Circuitry

Microwave Plumbing Replaces Circuitry, September 1948 Radio & Television News - RF CafeHere is a great treatise on waveguide theory put in layman's language, compliments of Samuel Freedman and DeMornay Budd. Although published in a 1948 issue of Radio & Television News magazine at a time when microwave frequencies were just coming into common use, the language and descriptive drawings are similar to what you will find in modern textbooks. Waveguide is not practical for use at lower frequencies because the physical dimensions are prohibitively large. For instance, for the FM radio band (88-108 MHz), waveguide width for a TE10 cutoff frequency at 88 MHz is around 67.5 inches. According to Wikipedia, the first waveguide was proposed by J.J. Thomson in 1893 and experimentally verified by Oliver Lodge in 1894...

Digital Pre-Distortion Test Times PA's Shortened

Digital Pre-Distortion Test Times PA's Shortened - RF CafeKeysight Technologies has introduced a new Iterative Learning Control (ILC) test method that significantly shortens Digital Pre-Distortion (DPD) test times for power amplifiers. Power amplifiers (PA) are a core component of wireless communication devices. Characterization of these components is a critical but time-consuming task that can take hours or even days during the R&D phase. By shortening the time it takes to complete the design and validation process, power amplifier manufacturers are able to accelerate their time-to-market. Keysight meets this need by introducing the innovative ILC DPD test method that shortens DPD test time to minutes and accelerates R&D time from test validation to product design and optimization. As a part of Keysight's comprehensive High-Frequency Measurement Solution portfolio, the ILC test method runs...

Anatomy of a Lightning Bolt

Anatomy of a Lightning Bolt, March 1973 Popular Electronics - RF CafeMankind has been fascinated with - and scared of - lightning since the dawn of civilization. It's incredible power has been the cause of much property destruction and loss of life. Benjamin Franklin famously proved that lightning is in fact a form of electrostatic discharge (he didn't "invent" electricity). Mr. Franklin exploited that knowledge to invent grounded lightning rods for tall buildings, thereby nearly totally halting the lightning-caused fire epidemic in Philadelphia's and other cities' tallest wooden-framed buildings. Much investigation and implementation of lightning discharge mitigation schemes has occurred to safeguard against those catastrophic events. Ultimately, though, says author David Heiserman in this 1973 Popular Electronics magazine article, "Lightning has no sympathy for the feeble electrical schemes of civilized man..."

Promote Your Company on RF Cafe

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 17,000 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. If you need your company news to be seen, RF Cafe is the place to be.

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 12th

Daylight Saving(s) Time vs. Standard Time

Daylight Saving Time vs. Standard Time - RF CafeTo be or not to be - that is the question: Whether 'tis nobler in the mind to suffer the slings and arrows of outrageous bi-annual clock shifts, or to take up arms against a sea of contradicting justifications for and against the existence of "Daylight Saving(s) Time," and by opposing, end it. (apologies to Will Shakespeare and Prince Hamlet) Twice each year, a majority of the western world is subject to a manmade disruption in circadian and habitual cycles with an inane one-hour clock change on and off of DST. Some historians claim that Benjamin Franklin joked about DST in the 18th century, but it was New Zealander George Hudson who proposed the modern day clock shift scheme in 1895. Germany, on April 30, 1916, was the first country to officially adopt DST. Since then, many other countries have gone onto and off of Daylight Saving Time. The motivation varies from saving coal during wartime to giving farmers more daylight for tending to crops to keeping school kids from being run over by cars on dark mornings. As you might expect, "expert" evidence is presented in abundance both for and against each issue. Every spring and fall (actually now winter and fall) the debate begins anew regarding whether DST is still needed. Some people want to retain the twice-yearly clock shift, some want year-round Daylight Saving Time, and most of the rest (including me) want year-round Standard Time (ST)...

Electronics Theme Crossword for March 12

Electronics Theme Crossword Puzzle for March 12, 2023 - RF CafeThis custom RF Cafe electronics-themed crossword puzzle for March 12th contains only words and clues which pertain strictly to the subjects of electronics, mechanics, power distribution, engineering, science, physics, astronomy, chemistry, etc. If you do happen see names of people or places, they are directly related to the aforementioned areas of study. As always, you will find no references to numbnut movie stars or fashion designers. Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds of them dating back to the year 2000. Enjoy.

Please Thank RF & Connector Technology for Their Support

RF & Connector Technology - RF CafeProviding full solution service is our motto, not just selling goods. RF & Connector Technology has persistently pursued a management policy stressing quality assurance system and technological advancement. From your very first contact, you will be supported by competent RF specialists; all of them have several years of field experience in this industry allowing them to suggest a fundamental solution and troubleshooting approach. Coaxial RF connectors, cable assemblies, antennas, terminations, attenuators, couplers, dividers, and more. Practically, we put priority on process inspection at each step of workflow as well as during final inspection in order to actualize "Zero Defects."

Friday the 10th

Missile Control and Guidance

Missile Control and Guidance, August 1960 Radio-Electronics - RF CafeIt is no stretch of the truth to say a sub-$100 remote-controlled drone or airplane from the toy aisle in Walmart today has more sophisticated guidance and stability control than the most advanced missile available in 1960, when this "Missile Control and Guidance" article appeared in Radio-Electronics magazine. Multi-axis accelerometers, processors, motor controllers, and even wireless off-vehicle communications are integrated into a couple (or a few, depending on the capabilities of the platform) integrated circuits. A full-color camera, possibly on a controllable gimbal, might be part of the system. True, scaling vehicle control mechanisms up to handle the rugged environment of a real-world missile with critical propulsion, flight, targeting and detonation mission requirements requires much more engineering than a toy aircraft. My point is that the heart of the system in 1960 was more crude and less capable than today's recreational vehicles. It is akin to how your smartphone has more computing and data storage capability than a 1960's era mainframe computer - and significantly more than the Apollo 11 flight control computer that delivered three men to and from the moon...

Brightest Light Quiz

Brightest Light Quiz, April 1964 Popular Electronics - RF CafeThis "Brightest Light Quiz" created by Robert Balin appeared in the April 1964 issue of Popular Electronics magazine. I might have titled it "The Brightest Bulb in the String Quiz" in reference to the saying about how "bright" someone is or is not. Figuring out the answer is a relatively simple matter of determining which branch of the circuit has the most current flowing through it. Some, like circuit A, are pretty easy by noting that all the current flows through just one of the bulbs, so that has to be the brightest. Re-drawing, either mentally or on paper, helps with circuits C, G and J and a few others. Un-cross lines and/or combine nodes with no bulb between them that are at the same potential. Circuit J is probably the most challenging, so re-drawing it is worthwhile...

Synzen Nordic nRF9160 Development Platform

Synzen Precision Technology Nordic nRF9160 Module - RF CafeDesigning IoT products just got a whole lot easier. Synzen Precision Technology, a leading provider of IoT solutions, has announced the launch of a new development platform that uses the advanced capabilities of the Nordic nRF9160 module. This new platform is designed to simplify the creation and deployment of IoT projects while ensuring seamless connectivity and secure data transmission. The Nordic nRF9160 module is a highly advanced chip that supports LTE connectivity, Bluetooth Low Energy (BLE), and Global Navigation Satellite System (GNSS). Using innovative antenna design techniques, engineers at Synzen have developed a new LTE solution whereby no band switching networks are required, which greatly reduces costs, complexity, and required PCB real estate. The whole package comes in a small form factor, measuring a compact 50x50 mm...

Under a Telephone Pole, by Carl Sandburg

Under a Telephone Pole, by Carl Sandburg - RF Cafe"There is no new thing under the sun." - Ecclesiastes 1:9. "Everything old is new again." - Peter Allen in All That Jazz. Many such idioms exist regarding how often things tend to run in cycles; it's just that often times people who think they are witnessing a new phenomenon are not aware of the previous occurrences. An article titled "OMG! We've Been Here B4," by Clive Thompson, appeared in the March 2016 issue of Smithsonian magazine, wherein he points out how many people believe the advent of texting is leading to the demise of courteous social spoken intercourse. Unlike holding a face-to-face or telephone conversation where both parties are intimately engaged in a conversation where each can discern whether the other hears what is being said and can expect a response, texting provides an easy excuse for ignoring any portion of the communications and blaming it, if challenged, on not having received or not having noticed the text message. He alludes to the following poem by Carl Sandburg (c1916) entitled "Under a Telephone Pole..."

RF & Electronics Symbols for Office™

RF & Electronics Schematic & Block Diagram Symbols for Office™ r2 - RF CafeIt was a lot of work, but I finally finished a version of the "RF & Electronics Schematic & Block Diagram Symbols" that works well with Microsoft Office™ programs Word™, Excel™, and Power Point™. This is an equivalent of the extensive set of amplifier, mixer, filter, switch, connector, waveguide, digital, analog, antenna, and other commonly used symbols for system block diagrams and schematics created for Visio™. Each of the 1,000 or so symbols was exported individually from Visio in the EMF file format, then imported into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or down without becoming pixelated, so all the shapes can be resized in a document and still look good. The imported symbols can also be UnGrouped into their original constituent parts for editing. Check them out!

Thanks to Wireless Telecom Group for Their Support!

Wireless Telecom Group (RF power and noise measurement) - RF CafeThe Wireless Telecom Group, comprised of Boonton, Holzworth, and Noisecom, is a global designer and manufacturer of advanced RF and microwave components, modules, systems, and instruments. Serving the wireless, telecommunication, satellite, military, aerospace, semiconductor and medical industries, Wireless Telecom Group products enable innovation across a wide range of traditional and emerging wireless technologies. A unique set of high-performance products including peak power meters, signal generators, phase noise analyzers, signal processing modules, 5G and LTE PHY/stack software, noise sources, and programmable noise generators.

Thursday the 9th

Novice Crossword Puzzle

Novice Crossword Puzzle, April 1964 Popular Electronics - RF CafeThis vacuum tube shaped crossword puzzle appeared in the April 1964 issue of Popular Electronics magazine. It won't take you more than a couple minutes to complete - just a short trip, with a pencil, to the John ;-)  Like with all my custom-made RF Cafe Crossword Puzzles, every clue and word in this crossword by Stephen Nelson has an application to electronics technology. Unlike with my crosswords, the across/down grid is very simple with few groups of adjacent empty squares. That makes creation an easier task, especially when your word selection list is constrained to a particular topic. Still, it's a good puzzle. Have fun.

Radio Debunked

Radio Debunked, March 1935 Radio-Craft - RF CafeThis is a true story. When I was in 9th grade, the class was being shown a film (yes, the celluloid type on a reel, on a projector, circa 1972-73) where the narrator mentioned how someone had committed a "boner." A girl in the class busted out laughing so hard that she actually wet herself. That made the rest of the class laugh. I guess she had never heard the word used in that context before - remember, we're talking teenagers in the 1970's. Sorry for the rude reference, but for some reason the incident came to mind when reading the section labeled "Radio Boners" in this article from a 1935 edition of Radio-Craft magazine. Funny what triggers a particular memory. All that has nothing to do with C.W. Palmer's fine story that addresses some of the common misconceptions about the relatively new technology called "radio," when even a term like "speaker" might cause confusion...

Micro-Supercapacitors Built into IC's

Micro-Supercapacitors Built into IC's - RF Cafe"Researchers at the Dalian Institute of Chemical Physics have found a way to deposit micro-supercapacitors consistently on surfaces such as silicon as a way to add energy storage directly to ICs. This is not the first time that supercapacitors have been deposited on such substrates, but the team claims to have combined unprecedented cell density, electrochemical performance and cell-to-cell consistency – the latter important if series-connected cells are to have a long charge-discharge cycle life. Dalian institute micro super capacitors. The basic structure is planar, with capacitance developed between interdigitated electrodes on the same flat surface..."

Coronet Model C-2 Schematic & Parts List

Coronet Model C-2 Schematic & Parts List, February 1947 Radio News - RF CafeYou wouldn't know it from the schematic, but this Coronet Model C2 tabletop radio has a very unique feature: The tuning scale/pointer, and volume and tuning knobs are on the top of the case, that is, the face of the radio points upward when properly displayed. When searching for photos of the Coronet C2, I found a few examples where the radio was sitting on a surface with the face situated vertically like a standard model, but the feet are clearly on the side opposite the face. The schematic and parts list for the Coronet C2 radio appeared in the February 1947 issue of Radio News magazine. There are still many people who restore and service these vintage radios, and often it can be difficult or impossible to find schematics and/or tuning information. I keep a running list of all data sheets to facilitate a search...

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 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.

Wednesday the 8th

Parallel Series Resistance Calculator

Parallel Series Resistance Calculator, August 1960 Radio-Electronics - RF CafeNomographs for calculating and converting values for resistance, capacitance, inductance, transformer coupling, frequency and wavelength, path loss, resonant frequency, AC impedance, and other parameters appeared in many magazines over the decades. In the days before handheld electronic calculators and, nowadays, smartphones, the use of a nomograph provided rapid solutions for sometimes complex mathematical equations. This particular nomograph calculates resistor values in series and parallel, where two resistors are combined to yield the required resistance. Series resistances are a simple matter of addition, but parallel resistance requires combinations of addition, multiplication, and division. Multiplication and division could be carried out with the help of a slide rule, but addition was still done by hand (slide rules don't do addition or subtraction). A unique feature of this particular "Parallel Series Resistance Calculator" from the August 1960 issue of Radio-Electronics magazine is the inclusion of a straight edge component for cross-referencing the two scales on the chart. While it might seem clever...

Compound Eye Space Radar China

Compound Eye Space Radar China - RF Cafe"China's ambitions to build the world's most powerful space observation radar - to peer further out and with greater detail than ever before - moved a step closer on Tuesday, with the start of work on stage two of the China Compound Eye. Long Teng, president of the Beijing Institute of Technology (BIT), which is leading the project, said that once completed, Chongqing, where the project is based, 'will become the world's capital of asteroid research '[The] launch of the second phase of the China Compound Eye project marks a new stage of our research. It will promote the development of high-end industries such as big data, electronic information, and satellite internet in Chongqing,' he said, in a BIT statement..."

Copyleft vs. Copyright

You've Heard of a Copyright, But How About a Copyleft? - RF CafeA copyright, as you know, is legal protection against unauthorized usage or obvious modification of original creative works, something most people who generate valuable works like because it represents a right to private property. A copyleft, on the other hand, is an alternative which permits free distribution of original works with the only restriction being that it and/or derivative works also be declared copyleft material. Note how evil Capitalist companies like IBM, Artech House publishers, and Rohde & Schwarz copyright and patent everything they create in order to benefit financially from the work of their employees. Doing so allows them to provide good wages and benefits while creating useful goods and services for customers. Liberal-dominated companies like Google, Apple, and Facebook, by contrast, allow everything they create to be freely copied and/or modified by anyone. Their only concern is the welfare of fellow men. Oh, wait. The fact is those kinds of companies also copyright and patent everything they create...

R&S: Drone Based Analyzer for ATC Navigation Signal Inspection

Rohde & Schwarz: Drone Based Analyzer for ATC Navigation Signal Inspection - RF CafeCivil aviation requires accurate and reliable navigation systems for optimizing air traffic control (ATC) and ensuring the essential public safety while mitigating aircraft risks, delays and costs. Terrestrial air navigation systems, such as landing systems or en-route navigation systems require unique test and measurement capabilities. The R&S EVSD1000 VHF/UHF nav/drone analyzer is a signal level and modulation analyzer for medium-sized drones. It is the only instrument that combines measurements of instrument landing systems (ILS), ground-based augmentation systems (GBAS) and VHF omnirange (VOR) ground stations in a single box. The mechanical and electrical design is optimized for drone based, real-time measurements of terrestrial navigation systems with up to 100 measurement data sets per second. The analyzer provides high-precision signal analysis in the frequency range from 70 MHz to 410 MHz, a critical requirement for drone based terrestrial navigation signal measurement systems...

National Company Advertisement

National Company Advertisement, April 1942 QST - RF CafeThe National Company of Cambridge, Massachusetts, was one of the first large distributors of electronics components and appliances. It began life as the National Toy Company. Under the leadership of Mr. James Millen, W1HRX, National quickly became a market leader in designing and marketing high quality radio products for both amateur radio operators and casual listeners of shortwave radios. National Company very often ran full-page advertisements in the American Radio Relay League's QST magazine, that were more in the form of an infomercial than pure product promotion. This one, number 98 in a very long-running series, extolls the virtues of their famous NSM Modulator. The majority of these ads were written my Mr. Millen, but in this case it was done by Calvin Hadlock. A bit of trivia: National Company was the first paid advertiser in The Radio Amateur's Handbook...

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...

Many Thanks to KR Electronics for Long-Time Support!

KR ElectronicsKR Electronics has been designing and manufacturing custom filters for military and commercial radio, radar, medical, and communications since 1973. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop, equalizer, duplexer, diplexer, and individually synthesized filters for special applications - both commercial and military. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. All common connector types and package form factors are available. Please visit their website today to see how they might be of assistance. Products are designed and manufactured in the USA.

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Innovative Power Products Couplers
TotalTemp Technologies (Thermal Platforms) - RF Cafe

Anatech Electronics RF Microwave Filters - RF Cafe

Anritsu Test Equipment - RF Cafe