Homepage Archive - March 2022 (page 2)

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

Monday the 14th

How Much Will a Resistor Take?

How Much Will a Resistor Take?, July 1955 Radio-Electronics - RF CafeHere is a good treatise on resistor ratings - voltage, current, and power - with and explanation and handy-dandy chart for helping you figure out what type of resistor you need to suit the task at hand. It appeared in the March 1953 issue of Radio-Electronics magazine, at a time when resistors the size of a grain of salt were not invented yet (or for that matter even tinier resistors on semiconductor dice), but the principles are still the same. I do take issue with author Manly's assertion that there only being one reason resistors fail: "The burnout occurred only because the resistor carried too much current." He cites the failure (electrical and mechanical) of connected components often being responsible for the excess current, but does now allow for a mechanical failure of the resistor itself. A factory manufacturing defect or being subject to excess vibration, temperature or shock can cause resistor failure. So can "walking wounded" type damage done during the assembly process due to mishandling. I do like the description given of the visual signs of an overheated resistor right up to the point where the functionality-giving smoke escapes and the resistor stops working...

RCA 155-C Oscilloscope Advertisement

RCA 155-C Oscilloscope Advertisement, October 1945 Radio News - RF CafeDid you know RCA (Radio Corporation of America) used to manufacture and sell oscilloscopes? The Model 155-C oscilloscope was promoted quite aggressively in the mid 1940s as a breakthrough instrument. A quick Google search shows that not many survived, and they are not particularly sought-after by vintage test equipment collectors. It seems the quality of the metal chassis was not very good, although the electronics get high marks. You can pick one up on eBay occasionally for fairly cheap. Oscilloscope Museum has an example of an RCA 155-C oscilloscope (lots of links on the page to images, manual, etc., but they can be hard to find)...

Exotic 2D Materials Could Resurrect Hard Drive

Exotic 2D Materials Could Resurrect Hard Drive - RF Cafe"Look out, flash memory - low-power, instant-on computing newly possible. For about a decade, a range of materials known as 'multiferroics' has been promising to lead the way to the ultimate memory device, or, at the very least, the ultimate replacement to flash memory. Multiferroics are materials with two or more coexisting ferroic orders, such as ferroelectricity and ferromagnetism. The term 'ferroic' is the material property in which a material's electrons can be collectively switched by an external field, such as switching the orientation of their charge or magnetic spin. These multiferroics have been developed at labs to serve as room temperature magneto-electric memory devices that can be switched with just voltage rather than current. The aim has been that these materials could ultimately..."

Stacking 4, Z-Matched Yagis

Stacking Four Z-Matched Yagis, April 1952 Radio & Television News - RF CafeIt seems that creating almost cartoonish-looking antenna arrays for the purpose of signal gain and directivity are usually relegated to the domains of military and amateur radio practitioners, but this article from a 1952 edition of Radio & Television News magazine was done by the Channel Master Laboratories television antenna company. Successfully mounting and phasing even two antennas can be challenging, but in this case four Yagis were arrayed and tuned for operation. Trying to make the system work over the entire 4 octave band that is the VHF broadcast realm (54 MHz for channel 2 to 210 MHz for channel 13) would be nearly impossible without extremely complicated mechanical and electrical design, so the engineers satisfied themselves with one channel at a time and used an adjustable spacing scheme to accommodate all 12 channels. Extensive guying and bracing was required to withstand wind loads...

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 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. 

Sunday the 13th

Electrical Engineering Theme Crossword Puzzle for March 13th

Electrical Engineering Theme Crossword Puzzle for March 13th, 2022 - RF CafeThis custom-made Electrical Engineering-themed crossword puzzle for March 13th, 2022, is brought to you by RF Cafe. 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...

Many Thanks to Axiom Test Equipment for Continued Support!

Axiom Test Equipment - RF CafeAxiom Test Equipment allows you to rent or buy test equipment, repair test equipment, or sell or trade test equipment. They are committed to providing superior customer service and high quality electronic test equipment. Axiom offers customers several practical, efficient, and cost effective solutions for their projects' TE needs and is committed to providing superior customer service and high quality electronic test equipment. For anyone seeking a way to offload surplus or obsolete equipment, they offer a trade-in program or they will buy the equipment from you. Some vintage items are available fully calibrated. Please check out Axiom Test Equipment today!

Friday the 11th

Status of the Electronic Industry 1955

Status of the Electronic Industry, July 1955 Radio-Electronics - RF CafeIn this 1955 report on the status of the electronics industry, Radio−Electronics magazine editor Hugo Gernsback summarizes a presentation made by RCA president Charles Odorizzi to the Cleveland Society of Security Analysts. He began thusly: "Few if any industries, in such a relatively short period of time, have experienced such amazing growth as electronics. From 1940 to the war's end in 1945, the annual dollar volume of the industry increased from $500 million to $4.6 billion." So was born what President Dwight D. Eisenhower would in 1961 term the Military-Industrial Complex. Being a capitalist and small government type at heart, I am somewhat conflicted with the concept because on the one hand I eschew government controlling industry and academia (aka communism), yet on the other hand I recognize the need for maintaining a strong military in order to both deter and defend against foreign aggression. The same goes for allowing pure market forces to determine the direction of research and production without government intervention; the result would be the same as allowing a purely democratic form of government - the majority, even by a thin margin, would decide what everybody else does...

LEO Satellite Megaconstellations Present Dire Hazards

LEO Satellite Megaconstellations Present Dire Hazards - RF Cafe"A study reported in Nature, 'Satellite mega-constellations create risks in Low Earth Orbit, the atmosphere and on Earth,' in Scientific Reports by Aaron C. Boley and Michael Byers, says the rapid development of mega-constellations risks multiple tragedies of the commons. That could include tragedies to ground-based astronomy, Earth orbit, and Earth's upper atmosphere. The study asserts that international cooperation is urgently needed, along with a regulatory system that takes into account the effects of tens of thousands of satellites. 'The connections between the Earth and space environments are inadequately taken into account by the adoption of a consumer electronic model applied to space assets,' the authors said. 'For example, we point out that satellite re-entries from the Starlink mega-constellation alone could deposit more aluminum into Earth's upper atmosphere than what is done through meteoroids..."

Electronics on the Hurricane Ship

Electronics on the Hurricane Ship, October 1957 Radio & TV News - RF CafeIf you enjoy reading about instruments with names like the Eppley pyrheliometer and the conductivity bridge salinometer, then this article is for you. Long before there were Earth-imaging and environment-monitoring satellites, sonobouys, and autonomous robotic dolphins perpetually roaming the world's oceans, it was up to ships and crews to do the often perilous work. Even with the aforementioned remote sensing technology, it is still necessary for the detailed work to be carried out by humans at the study sites. Raging, swelling, stormy seas imperil the lives and well-being of everything aboard, but don't pity the scientists - they are there because they love what they are doing and thrive on the challenge. It is a seafaring tradition and trait that reaches back to the dawn of time. Landlubbers like myself appreciate the sacrifices of sailors from ancient days of yore as well as today's intrepid explorers. That said, I could do without the types who do "research" based on what the politically correct desired outcome is to prove some scientifically unsound theory ... and it usually involves receiving large sums of money for supporting "the cause..."

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.

Ukraine Conflict Chokes Neon Supply for Chipmaking

Ukraine Conflict Chokes Neon Supply for Chipmaking - RF CafeThanks to Bob D. for this. "Russia's invasion of Ukraine threatens to pile further pressure on chip manufacturing as a squeeze on the supply of rare gases critical to the production process adds to pandemic-related disruptions. Ukraine supplies about 50% of the world's neon gas, analysts have said, a byproduct of Russia's steel industry that is purified in the former Soviet republic and is indispensable in chip production. Manufacturers have already been reeling from shortages of components, late deliveries, and rising material costs, with companies that rely on chips, such as carmakers, facing production delays as a result. Many companies, including U.S. manufacturers Applied Materials and Intel, have said constraints would persist into 2023. Demand for raw materials is also expected to rise by more than a third in the next four years, as businesses such as the world’s biggest contract chipmaker Taiwan Semiconductor Manufacturing Company increase production..."

Bell Telephone Laboratories Scientific Quality Control

Bell Telephone Laboratories Ad, June 1946 Radio News - RF CafeRemember when you could hold a telephone conversation without having to allow a moment of time at the end of a sentence before responding in order to keep from "stepping on" the person on the other end? It used to be only overseas phone calls or maybe communicating to astronauts on the moon suffered such inconveniences, but talking to someone across town was like having a face-to-face discussion. More often than not - or so at least it seems - there is a noticeable delay between the time someone actually stops talking on the transmitter end and the time the audio stops at the receiver end. People who have never known otherwise accommodate the delay with no appreciation for how good phone calls used to be. This promotion by Bell Telephone Labs which appeared in a 1946 issue of Radio News magazine extolls the virtues of its "scientific quality control" innovation that produced repeatable...

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 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! 

Thursday the 10th

What Is This Thing Called Decibel?

What Is This Thing Called Decibel?, August 1931 QST - RF CafeThere is no such thing as too many good articles about the decibel, and this "What Is This Thing Called Decibel?" piece from a 1931 issue of QST magazine is definitely a good read. Decibels are a very convenient method for calculating changes in power, voltage, and current levels due to it being based on logarithms, thereby changing multiplication and division operations into addition and subtraction operations, respectively. Once explained, some initial fear felt by newcomers is assuaged. Thereafter, the most difficult aspect of decibels is mathematically converting between ratios and decibels. In delving into some of the history of the usage of the decibel, co-author McLaughlin mentions the "R" system (Readability) of describing signal strength, as opposed to the modern "S" units - an interesting bit of historical trivia. Keeping in mind that this was written in 1931, it is not too surprising to read the author mention the somewhat recent transition from communications over copper wires to "radio circuits through space..."

Salad-Dressing-Like Droplets Improve Printed Electronics

Salad-Dressing-Like Droplets Could Improve Printed Electronics - RF Cafe"The assembly of 2D nanosheets on the surface of emulsion nanodroplets leads to the stabilization of the emulsion and requires only a tiny amount of material - report physicists in the UK. Furthermore, the team has developed a model that allows fine-tuning of the solvent composition so the droplets could be used to create components for a range of applications from strain sensors to batteries. The emulsions also raise the possibility of printing large-scale devices in a matter of minutes, which could have an important impact on electronics fabrication. Wouldn't it be great to print with 2D materials such as graphene? The answer is yes for many reasons, but how to do so is a puzzle that has confounded scientists working with 2D materials since Konstantin Novoselov and Andre Geim first isolated 2D sheets of carbon (graphene) in 2004. A thousand papers have been published on this subject, but the question regarding printing remains open..."

Gas Prices in U.S. vs. Canada

Gas Buddy price U.S. Canada - RF CafeAccording to the GasBuddy website, gas in the U.S. is running more than $4US/gallon. In Canada it's about $1.70/liter ($1.33US, or about $5US/gallon). You can't blame the Ukraine conflict for that! We are being royally screwed by our governments. The U.S. was energy independent a little over a year ago and now we buy oil from Russia and other hostile nations. Soon it appears we will be importing oil from Iran again - the world's largest supporter of radical terrorists and a fledgling nuclear power. The party line claiming "There are 9,000 approved oil leases that the oil companies are not tapping into currently," is a load of crap. Most - if not all - of those are not deposits worthy of developing, and they know it. You and I now pay exorbitant prices for energy (gas, electricity, oil), and the price of producing, transporting, and stocking goods goes up along with it. We have empty shelves and sky-high inflation. Thanks for nothing to the morons who made this all possible. You know who you are. Thanks to Canadian MK for letting me know the GasBuddy price is $CAN/liter.

Anatech Electronics' Has 3 New Filter Models

Anatech Electronics Early March 2022 Product Announcement - 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 surface mount ceramic bandpass filter centered at 1450 MHz and a 95 MHz bandwidth, a 105 MHz crystal bandpass filter with SMA connectors, and a 444 MHz LC highpass filter with N 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...

Carl & Jerry: The Difference Detector

Carl & Jerry: The Difference Detector, October 1962 Popular Electronics - RF CafeGlass-encapsulated bi-reed magnetic switches were a relatively recent invention that came out of Bell Labs when this Carl & Jerry episode was published in Popular Electronics magazine in 1962. It seems like such simple and common components have been around forever, and they have for a growing portion of people in the electronics realm since that was more than half a century ago. As is often the case with John Frye's enterprising pair of teenage experimenters, the reader is treated to a tutorial on the operational theory of the switch, with its dependence on magnetization by induction. The story ends up being quite humorous, and reminds me a bit of the old All in the Family episode where a window salesman uses a photography light measuring meter to convince Archie he is actually detecting severe air drafts around the windows, when in fact it is merely registering a greater light level near a window...

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 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.

Wednesday the 9th

Electronics-Themed Comics in Radio-Electronics

Electronics-Themed Comics, February 1951 & February 1952 Radio-Electronics - RF CafeThese two electronics-themed comics appeared in the February 1951 and 1952 issues of Radio−Electronics magazine. For some reason there were not as many comics in that era. At the time, the world was very obsessed with wireless entertainment so it was the subject of many memes in print, talk, and video. Predating cable media, the often constant battle in trying to get good reception on radio and/or television was a very popular theme. Also predating a time when there was a TV in every room in the house, the possibility of a single set being able to satisfy the desired of multiple viewers simultaneously was also commonplace topic. The comic artists of the day could never imagine that seven decades later almost every person on Earth would be walking around with a high definition TV set in his/her pocket - and that many don't even think about it (the smartphone) being "wireless" because they have never had a "wired" device...

Substitution Jigs Speed Service

Substitution Jigs Speed Service, October 1957 Radio & TV News - RF CafeSure, you do it all the time, but at some point either someone probably suggested to you and/or showed you how to clip substitute components into a circuit in place of a suspected bad component while troubleshooting or maybe during the design or tuning process. Miniature circuits of today pretty much rule out using alligator clips to patch in a part, but sometimes it is possible to use miniature "J" clip leads or even pin probes to make the connection long enough to take a measurement. Since I do a fair amount of circuit work on other-than-RF applications, I often find myself using short insulated, stranded wires with mini alligator clips on each end to make connections. This "Substitution Jigs Speed Service" article from a 1957 issue of Radio & TV News magazine has a few tips for you...

ConductRF Flexible RF Cable Assemblies to 18 GHz

ConductRF Flexible RF Cable Assemblies to 18 GHz March 2022 - RF CafeConductRF's LSA series of low loss, performance flexible RF cable assemblies, provide microwave system designers with a versatile solution for most applications. Here we offer customers a solution for 0.086" dia. cable that facilitates greater flexibility and handling or, 0.141" dia. that exploits the same great performance but with almost half the loss. Connector options include SMA, Type-N, TNC & SMP that provide excellent VSWR between DC and 18 GHz, also solutions for MCX & SMB are available in a wide array of configurations. These assemblies are built using our own double shielded, FEP jacketed cable, that was developed specifically for performance solutions. With shielding effectiveness exceeding 90 dB through 18 GHz, these cables minimize the threat of cross-talk effect. ConductRF guarantees it's performance through 100% factory test prior to shipping. Additional options are also available with enhanced bonded strain relief...

Fast-Charging, Bendable Supercapacitor

Fast-Charging, Long-Running, Bendable Supercapacitor - RF Cafe"A new bendable supercapacitor made from graphene has been developed that charges quickly and safely stores a record-high level of energy for use over a long period. The technology overcomes the issue faced by high-powered, fast-charging supercapacitors: they usually cannot hold a large amount of energy in a small space. The new supercapacitor is extremely promising for next-generation energy storage technology as either a replacement for current battery technology, or for use alongside it, to provide the user with more power. It was designed with materials that give it a high power density and a high energy density. It also can bend to 180 degrees without affecting performance and doesn't use a liquid electrolyte, which minimizes risk of explosion and makes it suitable for integrating into phones or wearable electronics. A graphene electrode material with pores can be changed in size to store the charge more efficiently. This tuning maximizes the energy density..."

Television in Great Britain

Television in Great Britain, January 1945 Radio News - RF CafeTelevision development was a distant memory for most people during the dark days of World War II. Germany's forces launched its second siege of the 20th century against Europe in Fall of 1939. By January of 1945, even the Brits were beginning to feel confident that the seemingly endless days of World War II were about to come to an end. Hitler's forces had been beaten back from its massive sprawl across Europe and into northern Africa. Eisenhower's D-Day campaign six months earlier had broken the back - and much of the will - of German forces. The Battle of Leyte Gulf shortly thereafter severely damaged Japanese naval forces. Slowly but surely improvements were made in TV camera, broadcast, and local viewing technology in spite of the severe restrictions placed on component and manpower availability, both in the UK and in the U.S . John Logie Baird was England's most famous television pioneer, having developed the first practical broadcast system. His accomplishments were reported in this January 1945 edition of Radio News. Mr. Baird died the next year at age 57...

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.

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