Homepage Archive - September 2022 (page 3)

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

Wednesday the 21st

The Danger of Radar Waves

The Truth About the Danger of Radar Waves, March 1961 Popular Electronics - RF CafeHaving worked on S-band and X-band radar as a maintenance technician for a four-year hitch in the U.S. Air Force, articles like this one from a 1961 issue of Popular Electronics magazine always piques my interest. A lot of ground is covered here regarding some history on documented cases of unintentional human exposure to microwaves and laboratory experiments on animals exposed to microwave radiation. Author Ken Gilmore points out the difference between ionizing radiation from nuclear actions and reaction, and non-ionizing radiation from microwave generators. In today's political environment, facilities in Ukraine, China (Wuhan in particular), etc., would need to be secretly paid to do the animal experiments described herein. Some pretty incredible scenarios are described where radar technicians would stand in front of radiating antennas to keep themselves warm in cold climates, and one guy would stick his hand into an antenna horn to check whether the transmitter was on by noting if his hand got warm (probably causing a wickedly high VSWR on the output amplifier)...

What Is an RF Attenuator?

RF Demystified: What Is an RF Attenuator? - RF CafeFrom Microwaves & RF magazine: "This article covers the basics of attenuator ICs, including the various types, design configurations, and key specifications you'll need to know when specifying them. The attenuator is a control component, the main function of which is to reduce the strength of the signal passing through it. This type of component is generally used to balance signal levels in the signal chain, to extend the dynamic range of a system; provide impedance matching; and implement various calibration techniques in the end application design. From the key functional perspective, attenuators can be classified as fixed attenuators with an unchanging level of attenuation and variable attenuators with an adjustable level of attenuation. Depending on the form of attenuation control supported by variable attenuators, they can in turn be further classified as voltage variable attenuators (VVAs), featuring analog control, and digital step attenuators (DSAs) that are controlled digitally..."

X-Ray Inspection

X-Ray Inspection, April 1955 Popular Electronics - RF CafeX-ray inspection capability is a vital tool not just in medicine but in industry. During my tenure with a major cellphone power amplifier company as an RF Applications Engineer, I relied heavily on x-ray imaging for many of the teardown reports that I wrote on competitors' products. It included everything from determining metal layers in integrated circuits to deducing multi-layer ceramic PCB routing lines and distributed components to just getting a quick look inside a shielded enclosure without needing to disassemble it. A skilled x-ray technician can make a huge difference in the quality of information that can be gleaned from the images since angle, power level, and focusing takes a deft touch. My first experience with using x-rays for inspection was while doing automated test system design for production base station equipment companies. Very stringent PIM (passive intermodulation) specifications were required for high power filters in order to minimize 3rd and higher level intermods. The N-type connectors ended up being the Achilles' heel of the switching filter matrix, and we had ordered a large quantity from one highly qualified manufacturer...

PCB Material Reference Guide

San Francisco Circuits: San Francisco Circuits: PCB Material Reference Guide - RF Cafe - RF CafePrinted circuit boards (PCBs) can have a major impact on electrical systems so the materials used when creating them should be carefully considered. San Francisco Circuits has put together a "PCB Material Reference Guide" to assist with making these decisions. Some of the key PCB characteristics to consider include the dielectric constant, dissipation factor, thermal conductivity, and coefficient of thermal expansion. Each is explained in detail along with some commonly available materials by the manufacturer that can be used when constructing PCBs. A comparison chart is also included so that readers can then quickly compare the characteristics of each material and determine what would be best for their PCB’s specific application. This reference guide has been carefully created by the experts at San Francisco Circuits to help readers determine the best material to use when constructing PCBs based on their specific applications...

Tube Characteristics & Data Chart

Tube Characteristics & Data Chart, February 1933 Radio-Craft - RF CafeHere is a vacuum tube chart everybody needs. Well, not really, but surely somebody out there in the RF Cafe audience will find it useful. By "audience" I mean most likely a hobbyist who is restoring or repairing a vintage tube-type radio, television, piece of test equipment, etc., and has never even heard of RF Cafe, but finds exactly what he/she needs as the result of a Google (Bing, Yahoo, whatever) search. If it seems like you can find information on just about anything you need on the Internet these days, it is at last partly because of efforts like mine that uses a lot of personal time and some personal funds to establish and perpetuate the reality. Others of you contribute in different ways; this is mine. A helpful way to make it worthwhile is to visit websites of companies that advertise on RF Cafe. A lot of great products and services are offered, and it doesn't cost you a penny to investigate...

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 Thank Lotus Communication Systems for Their Support!

Lotus Communication Systems Modular RF/Microwave Components - RF CafeLotus Communication Systems began in 2009, setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex Country, Massachusetts. Lotus is committed to highest quality and innovative products. Each RF/microwave module meets exceedingly high standards of quality, performance and excellent value, and are 100% MADE IN USA. Lotus' RF/microwave products cover frequency band up to 67 GHz. Lotus also offers an COTS shield enclosures for RF/microwave prototyping and production. All products are custom designed. We will find a solution and save your time and cost. Lotus has multiple 4 axis CNC machines and LPKF circuit plotters.

Tuesday the 20th

Carl & Jerry: A Low Blow

Carl & Jerry: A Low Blow, March 1961 Popular Electronics - RF CafeJohn T. Frye's "Carl & Jerry" technodramas are always both eventful and instructive in the realm of electronics and physics, but Mr. Frye really outdoes himself with this "A Low Blow" episode from the March 1961 issue of Popular Electronics magazine. The gist of the story is how they boys construct and use an "infrasonic" microphone to detect low audio frequency sounds. Information provided by the National Bureau of Standards (NBS, now the National Institute of Standards and Technology - NIST) served as the basis for designing and implementing a measurement system that ultimately resulted in a situation which provided the title "A Low Blow." You might be surprised to learn that low frequency sound waves are subject to atmospheric properties similar to radio waves, which can produce areal skipping and hopping phenomena where reception is possible only in certain regions between the source and the receiver. This is a very interesting read...

50 Most Expensive Colleges in America

50 Most Expensive Colleges in America - RF CafeMoneyWatch (CBS) recently published their survey of America's 50 most expensive colleges. It included both liberal arts and engineering schools. I expected the usual suspects like Ivy League and top engineering institutions like Harvard and Rensselaer Polytechnic Institute (RPI), respectively, to head the list, but was surprised to find that neither was included - shocking to say the least. Stanford, at #50, was at the bottom, costing a mere $74,570 per annum (for "privileged" students who foot their entire bill). At #23, Cornell runs $76,258. #18 Yale will set you (or your parents) back $76,645 per year. Calling yourself a Duke (#18) Blue Devil carries a $77,029/year price tag. Harvey Mudd, always at the top of all sorts of lists, is #3 at $79,539 per year. Believe it or not, the most expensive college in America is University of Chicago. Every year you survive without getting shot costs you a hefty $81,531. There you go.

How We Listen to Stars and Satellites

How We Listen to Stars and Satellites, February 1958 Popular Electronics - RF CafeIf you have never paid much attention to the state of the art in telescopes, then you might believe they consist of either the $99 Tasco jobs in Walmart's toy department or the 200" Hale atop Mount Palomar, with not much in−between. You might also think that objects which emit or reflect light in the visible spectrum are the only things studied. You might not know that telescopes have been built to detect frequencies ranging from HF all the way up into cosmic rays. Newer telescopes search for gravity waves and even neutrino and "dark matter" pseudo particles. You might not know that there is a broad selection of optical telescopes for amateur and research grade telescopes and that the line between amateur and research grade telescopes grows less distinct every year. Even radio telescope equipment is beginning to hit the market. This article gives a nice intro to the subject of radio telescopy; the basics haven't changed...

Electronics Companies' Magazine Ads

Electronics Companies Magazine Ads August 2022 Microwave Journal) - RF CafeIt has been my belief for a long time that the vast majority of print magazine advertisements are never seen by potential customers because very few of those potential customers ever bother to pick up a print magazine. More than a decade ago (around 2007) when I was spending my last days working in a corporate environment, I do not ever recall seeing anyone reading a trade magazine, be it Microwave Journal, Microwaves & RF, Electronic Design, EE|Times, or any of the others. In fact, most of the magazines I saw were deposited in the mail room recycle or trash bin before they ever made it to an engineer's, technician's, or manager's desk. That is not to say or imply the magazines are not excellent - they are, indeed - but even back then most people were getting their needed information online. Being able to show a print version circulation number to advertisers does not in any way correlate directly to the number of potential customers who will ever see their advertisements...

United Screw and Bolt Corporation Advertisement

United Screw and Bolt Corporation Advertisement, January 1946 Radio News - RF CafeClutch head screws were one of the original "security" or "tamper-proof" type fasteners. United Screw and Bolt Corporation undoubtedly hoped their patented design would become the new standard in screw heads and drivers. Clutch head screws are still available today, but many do not include the round shape in the middle of the "bowtie" shape. Fortunately for Mr. Henry Phillips, his eponymous screw head design, first introduced a decade earlier than when this advertisement appeared in Radio News magazine, won out in the battle to replace the straight slot screw type. Any kind of screw head that captures the driver to prevent it from slipping off the head and stabbing into and/or scratching the work piece is a welcome improvement...

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 ISOTEC for Continued Support!

ISOTEC Corporation - RF CafeSince 1996, ISOTEC has designed, developed and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components and filters for wireless service providers including non-magnetic connectors for quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM RF connectors components such as power dividers and directional couplers. Off-the-shelf and customized products up to 40 GHz and our low-PIM products can meet -160 dBc with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and high-performance. Designs that are cost effective practical and repeatable.

Monday the 19th

Mica Capacitors

Mica Capacitors, July 1965 Electronics World - RF CafeMica capacitors of the leaded, dipped type were used quite a bit in the military electronics assemblies I used to build in the early and middle 1980's while working at Westinghouse Electric Corporation's Oceanic Division in Annapolis, Maryland. They had the characteristic medium brown color and were shiny. According to Arco Electronics author E. M. Rothenstein, mica is one of a very few natural materials directly adaptable for use as a capacitor dielectric. "Mica, being a natural mineral and adapted to use without physical or chemical alteration, is completely inert both dimensionally and electrically. As a dielectric, it will not exhibit aging or deterioration nor subtle variants in electrical properties." In 1965 when this article appeared in Electronics World magazine, mica capacitor tolerances were in the realm of ±0.25%, which is amazingly good, and were useable over the full -55 to +150°C MIL-SPEC range. Values from 1 pF through 1 μF were available. Most likely modern processes have found a way to improve on the natural characteristics. In fact, this 2022 Cornell-Dubilier datasheet for their line of surface mount mica capacitors suggests (IMHO) they are the world's most perfect capacitor...

Domain-Wall Discovery Points Toward Self-Healing Circuits

Domain-Wall Discovery Points Toward Self-Healing Circuits - RF Cafe"Atomically thin materials such as graphene have drawn attention for how electrons can race in them at exceptionally quick speeds, leading to visions of advanced new electronics. Now scientists find that similar behavior can exist within two-dimensional sheets, known as domain walls, that are embedded within unusual crystalline materials. Moreover, unlike other atomically thin sheets, domain walls can easily be created, moved, and destroyed, which may lead the way for novel circuits that can instantly transform or be repaired on command. In the new study, researchers investigated crystalline lithium niobate ferroelectric film just 500 nanometers thick. Electric charges within materials separate into positive and negative poles, and ferroelectrics are materials in which these electric dipoles are generally oriented in the same direction. The electric dipoles in ferroelectrics are clustered in regions known as domains. These are separated by two-dimensional layers..."

Electronics-Themed Comics, September 1949

Electronics-Themed Comics, September 1949 Radio & Television News - RF CafeWhat better way is there to resuscitate a challenging work day than to kick back and enjoy these electronics-themed comics from a vintage edition of Radio & Television News magazine? Seeing a comic panel in any modern technical magazine these days is rare, if for no other reason than a fear amongst publishers (and their lawyers) that somebody, somewhere might be offended. You have my invitation to create a good-humored cartoon about me or RF Cafe anytime you wish, and I promise not to sue you. I'll even post it here on the website if you like. BTW, these comics make great fodder for the front page of your technical presentations - a good way to soften the edge going into a meeting, especially if you are not good at delivering jokes...

Element Spacing in 3-Element Beams

Element Spacing in 3-Element Beams, October 1947 QST - RF CafeThis rather extensive article from a 1947 issue of QST magazine describes the method used by author Philip Erhorn to experimentally (i.e. empirically) determine optimum spacing for the parasitic elements of his antenna. Unless you have electromagnetic field simulation software available for designing antennas, the procedure typically involves beginning with published formulas for element length and spacing, then resorting to a cut-and-test method of finding a combination that works best for your installation and goals. Almost certainly no two Hams end up with identical configurations because differences in terrain, physical obstacles, antenna height, soil conductivity, test methods and available equipment, and ability to interpret results affect outcomes. Even with software like "EZNEC" (free as of January 2022) and more sophisticated professional programs like NI/AWR's "Analyst" and Keysight Technologies' "Momentum," significant variations can occur one an antenna is deployed in an operational environment...

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 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.

Sunday the 18th

Ham Radio Theme Crossword Puzzle for September 18th

Ham Radio Theme Crossword Puzzle for September 18th, 2022 - RF CafeThis September 18th 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. Enjoy!

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 Thank IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products (IPP) has over 35 years of experience designing & manufacturing RF & microwave passive components. Their high power, broadband couplers, combiners, resistors, baluns, terminations and attenuators are fabricated using the latest materials and design tools available, resulting in unrivaled product performance. Applications in military, medical, industrial and commercial markets are serviced around the world. Products listed on website link to detailed mechanical drawings that contain electrical specifications as well as performance data. Please take a couple minutes to visit their website and see how IPP can help you today. 

Friday the 16th

Showdown for the FCC?

Showdown for the FCC?, May 1960 Popular Electronics - RF CafeMy, how times have changed. In 1960 when this article entitled "Showdown for the FCC?" appeared in Popular Electronics magazine, the Federal Communications Commission was being criticized for its failure to properly regulate, monitor, and police broadcasters who were granted licenses to occupy commercial airwaves. The FCC faces similar issues today covering a much wider assortment of spectrum bands, but this particular piece was triggered by a "whistleblower" (a popular term in today's news) who discovered outcome rigging by the producers of CBS's "Dotto" television quiz show in 1958. The public, feeling violated by the Columbia Broadcasting System, used it as a springboard for protesting the FCC's general lack of ignoring other responsibilities like preventing dishonest and/or misleading and/or "offensive" advertisement. To demonstrate how far decency standards have fallen in half a century, one of the products deemed not proper for airing during family programming time was Preparation H...

Anatech Intros 3 Filter Models for September 2022

Anatech Electronics Intros 3 Filter Models for September 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 2450 MHz cavity bandpass filter with N-type connectors, an 18 GHz stripline highpass filter with SMA connectors, and a 6790 MHz waveguide bandstop filter. Custom RF power filter and directional couplers designs can be designed and produced with required connector types when a standard cannot be found, or the requirements are such that a custom approach is necessary...

Tune Your Antenna with a String

Tune Your Antenna with a String, October 1949 Radio & Television News - RF CafeLots of Hams still use this tried-and-true "Tune Your Antenna with a String" system for tuning antennas for efficient operation on a variety of bands. There are plenty of multi-band designs that rely on traps to reactively isolate portions of the antenna that properly resonate at the desired frequency, but there is usually a price to be paid in VSWR. Poor VSWR; i.e., higher mismatch loss, can be overcome with higher transmitter output power, but the real sacrifice for poor matching is loss of receiving range. The utter simplicity of using an insulated cord to vary the physical length of the antenna element(s) for tuning is hard to beat. The scheme presented in the October 1949 issue of Radio & Television News magazine could be impractical on a setup where access to the antenna mount is difficult, but my guess is most people can make good use of it...

BAE to Launch Military LEO Secure Satellite Cluster

BAE Systems to Launch Military LEO Secure Satellite Cluster - RF Cafe"BAE Systems plans to launch its first multi-sensor satellite cluster into low Earth orbit in 2024 to deliver high-quality information and intelligence in real-time from space to military customers. Known as Azalea, the group of satellites will use a range of sensors to collect visual, radar and radio frequency (RF) data, which will be analyzed by onboard machine learning on edge processors to deliver the resulting intelligence securely, anywhere in the world while still in orbit. Following the acquisition of In-Space Missions last year, BAE Systems is one of a small number of British companies with the capability to design, build, launch and operate satellites. The expertise brought by In-Space Missions complements the Company's existing advanced technologies and will become an integral part of its multi-domain capability..."

Flying High at Zero Altitude

Flying High at Zero Altitude, December 1958 Popular Electronics - RFCafeMy flight simulator software (MS Flight Sim 2002) and computer it runs on (HP i7 notebook) are each more powerful than the software and computer that ran the Douglas DC-8 pilot training simulator featured in this 1958 article in Popular Electronics magazine. Two racks of 1000+ vacuum tubes did the figurative electronic heavy lifting while massive DC motors did the literal physical cockpit heavy lifting. The computer needed to handle as many as 40 variables at one time, including 6 differential equations of motion. 100 servomotors, 540 amplifiers and 2,200 gears drove the instrument panel gauges, dials, and movie projector mechanisms. The instrument panel description conjures images of the inside of a modern office-grade copying machine with its very dense conglomeration of gears and axels...

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...

Many Thanks to Bittele Electronics for Continued Support!

Bittele Electronics PCB Fabrication - RF CafeSince 2003, Bittele Electronics has consistently provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly services. It specializes in board level turnkey PCB assembly for design engineers needing low volume or prototype multi-layer printed circuit boards. Free Passive Components: Bittele Electronics is taking one further step in its commitment of offering the best service to clients of its PCB assembly business. Bittele is now offering common passive components to its clients FREE of Charge.

Thursday the 15th

Recent Developments in Electronics

Recent Developments in Electronics, July 1965 Electronics World - RF CafeThings were moving fast in the electronics development realm in the 1960s. Many relatively new technologies were undergoing rapid development due to a number of factors - high numbers of engineering and science students graduating from college, a huge demand by the commercial and consumer sectors for creature comfort products, the Cold War requirement for advanced weapons systems, and the advent of increasingly powerful computers for aiding the design process. Electronics World magazine ran a monthly column entitled "Recent Developments in Electronics" which reported on those activities. This July 1967 issue included the Early Bird communications satellite for supporting commercial telephone traffic and international television programming, a portable battlefield radar system, a radar transponder built with solid state devices rather than vacuum tubes, and the OSCAR III satellite designed and built by radio amateurs to enable Hams...

Europe's Undeclared Radio War!

Europe's Undeclared Radio War!, July 1938 Radio-Craft - RF CafeRadio was a powerful propaganda tool and strategic communications means toward the end of World War I, and certainly in the lead-up to and during the course of World War II. Many governments, including the United States and most European countries, forbade the broadcasting of signals by anything other than an entity licensed for commercial and/or military purposes. Amateur radio broadcasts were prohibited, although at least here in the U.S. possession of a receiver for listening was still allowed. Some of the regions controlled by Nazis did not even permit receivers - mainly because the government did not want citizens listening to anything that could be considered propaganda. Jamming of broadcast signals from "Allied" countries was routinely practiced by Hitler's and Mussolini's tight-fisted controllers. Many citizens were imprisoned or executed...

Many Thanks to Anatech Electronics for Long-Time Support!

Anatech Electronics logo - RF CafeAnatech Electronics (AEI) manufactures and supplies RF and microwave filters for military and commercial communication systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard RF filter and cable assembly products are published in our website database for ease of procurement. Custom RF filters designs are used when a standard cannot be found, or the requirements dictate a custom approach for your military and commercial communications needs. Sam Benzacar's monthly newsletters address contemporary wireless subjects. Please visit Anatech today to see how they can help your project succeed. 

RF Demystified: Types of Scattering Parameters

RF Demystified: Types of Scattering Parameters - RF CafeWith newcomers entering the field of RF and microwaves all the time, an introduction to and familiarity with scattering parameters (aka s−parameters) is a continuing issue needing to be addressed. Fortunately, there are plenty of knowledgeable people ready and willing to write tutorials for that purpose - in this case Anton Patyuchenko, in Microwaves & RF magazine. He begins: "Development of RF applications relies heavily on S−parameters to describe integral structures and constituent RF components at different frequencies and for different power levels of a signal. Scattering parameters (S−parameters), which describe the fundamental characteristics of RF networks, come in many flavors, including small signal, large signal, pulsed, cold, and mixed mode. They quantify how RF energy propagates through a system and thus contain information about its fundamental characteristics. Using S−parameters, we can represent even the most complex RF device as a simple N−port network..."

Electronics Themed Comics

Electronics Themed Comics, June 1940 QST - RF CafeTake a break from the workaday doldrums and enjoy a few vintage Ham-themed comics. Artist Phil Glidersleeve (aka "Gil"), W1CJD, created hundreds - if not thousands - of such comics for QST and other technical magazines during his multi-decade career. These appeared in the June 1940 issue. Most of these particular comics accompanied monthly columns and have a theme related to something within the text. However, I did not feel like processing all the text of those columns since it is not necessary to enjoy the humor depicted in the comics...

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 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.

Thanks Again for Windfreak Technologies' Continued Support!

Windfreak TechnologiesWindfreak Technologies designs, manufactures, tests and sells high value USB powered and controlled radio frequency products such as RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters. Since the conception of WFT, we have introduced products that have been purchased by a wide range of customers, from hobbyists to education facilities to government agencies. Worldwide customers include Europe, Australia, and Asia. Please contact Windfreak today to learn how they might help you with your current project.

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