Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives Magazine Sponsor RF Cafe Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Alliance Test Equipment Centric RF Empower RF ISOTEC Reactel RF Connector Technology San Francisco Circuits Anritsu Amplifier Solutions Anatech Electronics Axiom Test Equipment Conduct RF Copper Mountain Technologies Exodus Advanced Communications Innovative Power Products KR Filters LadyBug Technologies Rigol TotalTemp Technologies Werbel Microwave Windfreak Technologies Wireless Telecom Group Withwave RF Cafe Software Resources Vintage Magazines RF Cafe Software WhoIs entry for RF Cafe.com Thank you for visiting RF Cafe!
RF Cascade Workbook 2018 by RF Cafe

PCB Directory (Manufacturers)

Anatech Electronics RF Microwave Filters - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

RF Cascade Workbook for Excel

RF & Electronics Symbols for Visio

RF & Electronics Symbols for Office

RF & Electronics Stencils for Visio

RF Workbench

T-Shirts, Mugs, Cups, Ball Caps, Mouse Pads

These Are Available for Free

Espresso Engineering Workbook™

Smith Chart™ for Excel

LadyBug LB5954L Power Sensor with LAN Option - RF Cafe

Homepage Archive - April 2021 (page 4)

See Page 1 | 2 | 3 | 4 of the April 2021 homepage archives.

Friday the 30th

Radio Industry Unfair?

Radio Industry Unfair?, May 1946, Radio-Craft - RF CafeTo some extent, I agree with the readers of Radio-Craft magazine who wrote to editor Hugo Gernsback complaining about the lack of opportunity available to radio servicemen returning from the battlefield at the end of World War II. As noted in this editorial entitled, "Radio Industry Unfair?," many are people who sold or took leave from their established electronics service and/or stores in answer to their country's call to go abroad to fight for the free world. However, Radio-Craft was, throughout 1945, filled with advertisements by electronics manufacturers promising jobs and opportunities and anticipated demand for representation by service shops and sales outlets. Evidently, it did not turn out to be so, at least to the degree predicted. Gernsback does have a good point, though, that if the letters submitted to him are an indication of the quality...

High Throughput Satellites

High Throughput Satellites (Artech House) - RF CafeArtech House today announced the publication High-Throughput Satellites, by Hector Fenech. This exciting new book discusses the motivation for the evolution of a new breed of High Throughput Satellites (HTS) that have emerged from traditional communications satellites. It explores the commercial sectors and technical context that have shaped HTS. The historical underpinnings of HTS are provided to highlight the requirements that dimension these satellites. A survey of operational GEO HTS systems is also included. Readers will understand the technical, operational and commercial context of HTS systems, as well as the performance of the current HTS system. This initial breed of satellites was limited to geostationary satellites, but it is quickly projecting into low earth orbit (LEO) constellations, often referred to as mega-constellations. The industrial and operational facets of LEO constellations are challenging...

Thanks Again to Exodus Advanced Communications for Continued Support!

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

Nixie Tubes Add Victorian Charm to Projects

Add Victorian Charm with Segment Displays and Nixie Tubes - RF CafeThe Victorian era ran from 1837 through 1901, years prior to the 1955 advent of Nixie tubes, but I get what Clive "Max" Maxfield means when he wrote his article entitled, "Add Victorian Charm with Segment Displays and Nixie Tubes." Only a valvephobe (my word) could fail to appreciate the pleasing ambience contributed by the warm, orange glow of a vacuum tube. Max's article on the Design News website begins, "Modern incarnations of the technologies of yesteryear - such as Nixie tubes and 21-segment Victorian displays - add charm to modern devices. My current hobby project involves creating a 21st Century incarnation of a super-tasty 21-segment Victorian display technology. I will explain more in a moment, but first... I don't know about you, but I'm a big fan of the steampunk aesthetic, which I feature in many of my hobby projects. This is especially true in the case of display technologies. Take Nixie tubes, for example..."

A New Arm of the Law

A New Arm of the Law, March 1930 Radio News - RF Cafe"In my judgment, it will be only a few years before all police departments will be equipped with radio," Superintendent A. A. Carroll, Grand Rapids Police Department. Such a statement could have been deemed risky - or even career-ending back in the late 1920 to early 1930s when radio communications was still in its infancy. A lot of public figures denounced radio for anything other than a means of receiving entertainment at home. After all, the equipment was physically large and very power hungry. It was considered folly by many people to believe that an automobile's electrical generation capability would ever be able to power a vacuum tube receiver, much less a transmitter that would have enough range to be useful. Still, police and fire departments forged ahead and became some of the leaders in technology implementation. It was a huge deal in 1930 when a police station installed radios in its fleet of patrol cars, often requiring special fund raising activities or raiding of funds originally set aside for other projects...

IMS2021 and Microwave Week Registration for In-Person and Virtual Events

IMS2021 and Microwave Week Opens Registration for the In-Person and Virtual Events - RF CafeThe 2021 IEEE MTT-S International Microwave Symposium (IMS2021) and Microwave Week, the world's largest event for RF and microwave technology will be presented in a hybrid format, comprised of in-person and virtual participation options. With 200 exhibiting companies, IMS2021 will be host to the industry's top innovators. The in-person event will be held June 7-10, 2021 at the Georgia World Congress Center in Atlanta, GA. A virtual event will follow on June 20-25, 2021 with on-demand content available through the end of July. The theme for both events is "Connecting for a Smarter, Safer World." Registration is now open and there are a variety of options to provide as many people as possible the opportunity to participate. Registration for in-person IMS or RFIC gives access to the merged IMS and RFIC symposiums, technical lectures on Monday, and the exhibition...

Many Thanks to Nova Microwave for Continuing Support!

Nova Microwave Circulators & Isolators - RF CafeNova Microwave is a leader in technically differentiated electronic and radio frequency Ferrite Circulators and Isolators that connect, protect and control critical commercial and military wireless telecommunications systems. Our staff is dedicated to research and development of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz to 26.5 GHz. Available in single or multi-junction topographies, the Nova Microwave product line of is specifically designed for use in varied environmental and temperature extremes. 

Thursday the 29th

Electronics-Themed Comics

Electronics-Themed Comics, January 1940 Radio News - RF CafeHere are a couple more electronics-themed comics from a 1940-era issue of Radio News magazine. The scenarios depicted in these old comics are often based on the real-life experiences of radio and electronics servicemen. No doubt many guys got clobbered by high voltage or deafening audio when a customer decided to power up a television or radio while being worked on in the home. When this comic with the police car radio appeared in 1940, it had only been a decade since the first 2-way radios were being installed in patrol cars (see "A New Arm of the Law"). A huge list of technology-themed comics is listed at the bottom of the page. Enjoy!

Transistor-Like Device Controls Graphene's Electronic Properties

Transistor-Like Device Controls Graphene's Electronic Properties - RF Cafe"Researchers in Germany and Spain have created a transistor-like device that uses a small voltage to control the strength and frequency of electronic signals transmitted through graphene. The feat, which is detailed in Science Advances, marks an important step towards using graphene in electronic devices such as terahertz frequency converters, mixers and modulators. Graphene - a honeycomb-like lattice of carbon just one atom thick - has several unique electronic properties. Many of them stem from the fact that it is a semimetal with no energy gap between its valence and conduction bands. In the region where these two bands meet, the relationship between the energy and momentum of charge carriers..."

How Long Is 1 Trillion Seconds?

How Long Is 1 Trillion Secsonds? Kirt's Cogitations #327 - RF CafeEngineers are entirely comfortable with numbers multiplied by very large powers of 10; that is, with many trailing (or leading if a decimal) zeros after the significant figures. A terahertz is 1 x 1012, or 1 followed by twelve zeros, or 1,000,000,000,000 Hz. A picosecond is 1 x 10-12 s, or eleven zeros between the decimal point and the one, or 0.000000000001 s. The mass of the sun is approximately 1.9885×1030 kg, or 1,988,500,000,000,000,000,000,

000,000,000 kg. The mass of an electron is approximately 9.10938×10−31 kg, or 0.000000000000000000000000

000000910938 kg. We don't even break a sweat when punching those kinds of numbers into a calculator. We're used to it. When most laypeople these days hear politicians nonchalantly toss around figures in the trillions of dollars regarding a country's deficit or planned new spending packages, or the net worth of Amazon's Jeff Bezos, Tesla's Elon Musk, and Donald Trump, they have no concept of how big the numbers are...

A Passive RF Limiter

A Passive RF Limiter, December 1966 QST Article - RF CafeThis passive limiter is a simple combination of cascaded "T" type resistive attenuators that are switched in and out of the circuit based on the power level in the line. The design takes a bit of thinking due to needing to retain a reasonable impedance match at the input and output throughout various stages' conduction states. Arriving at an optimal value for resistors would require a circuit simulator with a mathematically based optimizer, but, especially for amateur radio work, close is good enough. That is not to say Hams are a bunch of slackers - they're not - it's just that component and software resources are not as readily available (aka "prohibitively expensive") for doing the analysis and testing. In 1966 when this article was published, software did not even exist for people without access to university or corporate computers. For most users these days, it is cheaper to buy a limiter for 2- to 3-score dollars...

FCC Keeps Shooting Down Drone Shoot-Down Systems

FCC Keeps Shooting Down Drone Shoot-Down Systems - RF Cafe"Regulators have denied testing permits to at least four electronic warfare systems in the last six months. When Hawthorne, Calif.-based startup Epirus decided to test a new electronic weapon last winter, it filed an application with the FCC. It wanted to test its high power microwave device in the California desert east of Palm Springs, about three miles from a small airport and the busy I-10 interstate. The unnamed prototype would be operated intermittently with an effective radiated power of 270 megawatts - thousands of times higher than the strongest FM radio stations, and in the same ballpark as controversial experiments that produce artificial aurorae - and have a range of 300 meters..."

Thanks to PCB Directory for Continued Support!

PCB  Directory - RF CafePCB Directory is the largest directory of Printed Circuit Board (PCB) Manufacturers, Assembly houses, and Design Services on the Internet. We have listed the leading printed circuit board manufacturers around the world and made them searchable by their capabilities - Number of laminates used, Board thicknesses supported, Number of layers supported, Types of substrates (FR-4, Rogers, flexible, rigid), Geographical location (U.S., China), kinds of services (manufacturing, fabrication, assembly, prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.

Wednesday the 28th

Radio-Electronics Monthly Review

Radio-Electronics Monthly Review, April 1946, Radio-Craft - RF CafeBelieve it or not, many countries did - and some still do - charge people wanting to receive over-the-air (not cable or satellite) commercial radio and/or television programming a wireless license fee for the privilege. Yes, this is for receiving, not transmitting, signals. If you dared to tune in a BBC program without a license, a fee could be expected upon detection (pun intended). The Monthly Review feature in this 1946 issue of Radio-Craft magazine reported an increase in cost to the equivalent of $29 in 2021 money (per the BLS Inflation Calculator). Also highlighted was a method for printing radio circuits made with conductive inks on ceramic sheets - known today as thick-film printing. An announcement of the U.S. War Department's 18,000-tube ENIAC electronic calculating device was made as well. The electronics field was moving quickly...

ConductRF Hi-Frequency Flexible RF Cable Assemblies

ConductRF Hi-Frequency Flexible RF Cable Assemblies April 27, 2021 - RF CafeConductRF's latest innovation is Hi−Frequency RF Jumper Cables with 2.92 mm, 2.4 mm or 1.85 mm connectors as standard. This assemblies use our optimized direct solder attached connectors and our superior double shielded hi-frequency A61SW flexible cable with shielding effectiveness greater than -100 dB. These cables are design to support the latest requirements for 5G applications for cross connecting modules, but can equally be used in any field where hi-frequency jumper cables are required. Beyond our standard interconnect, we can also offer solutions with SMP, SMPM, SMA and many other common connector interfaces. Hi-Performance right angled options are available utilizing hard setting shrink tube to form the cable bend...

Carl & Jerry: Aiding an Instinct

Carl & Jerry: Aiding an Instinct, December 1962 Popular Electronics - RF CafeBy 1962, John T. Frye's techie troubleshooting teenagers Carl and Jerry had graduated from high school and were attending Parvoo University (PU?) as electrical engineering students. It was a natural progression. Unlike many of the company names and products - like the Delco DN278 transistor mentioned here - that appeared in the Popular Science series, the college's name is fictional. Maybe author Frye had a connection to Porvoo, Finland, and Anglicized the name. Per RF Cafe visitor Jim P., "The stadium in the story is Moss-Ade stadium. The stadium at Purdue University is Ross-Ade stadium. I would guess that Parvoo comes from Purdue." According to a search I did to determine whether Frye ever attended Purdue, "Remarkably enough, he never attended Purdue University..."

Many Thanks to San Francisco Circuits for Continued Support!

San Francisco CircuitsSF Circuits' specialty is in the complex, advanced technology of PCB fabrication and assembly, producing high quality multi-layered PCBs from elaborate layouts. With them, you receive unparalleled technical expertise at competitive prices as well as the most progressive solutions available. Their customers request PCB production that is outside the capabilities of normal circuit board providers. Please take a moment to visit San Francisco Circuits today. "Printed Circuit Fabrication & Assembly with No Limit on Technology or Quantity."

Bittele Offers Automated Press-Fit Assembly

Bittele Electronics Offers Automated Press-Fit Assembly for Consistent and Reliable Quality - RF CafeBittele Electronics Inc., a Toronto-based one-stop PCB manufacturer specializing in prototype and low-to-mid volume printed circuit board assembly, announced today that it offers automated press-fit assembly as alternative to soldered connections in its PCB assembly services. Using automated pressing machines, Bittele achieves reliable and repeatable quality for all PCBs requiring press-fit components. Press-fit parts are not assembled using standard PCB Assembly practices, such as reflow soldering or wave soldering. Instead of soldering, press-fit parts are held in place by the plated holes themselves. Press-fit holes have very strict tolerance requirements, compared to standard plated holes for through-hole assembly...

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. 

Tuesday the 27th

Mac's Radio Service Shop: Tape Recorders

Mac's Radio Service Shop: Tape Recorders, March 1954 Radio & Television News - RF CafeAs mentioned in the past, most things you might want to find from the present or past can be found eventually on eBay. Such is the case with the Webster Electric Model 205 Tape Recorder mentioned in this Mac's Radio Service Shop episode which appeared in a1954 issue of Radio & Television News magazine. Here, Mac McGregor schools sidekick electronics technician Barney Jameson on the workings of a high quality tape recorder, including some of the ingenious methods devised for test and alignment. I especially like the magnetic tape specifically prepared for head alignment by the Toogood Recording Company of Chicago (yes, it was a real company, named after Mr. Louis S. Toogood). The recorded signal is 0.001 inch in wavelength and will reproduce at 7500 cycles-per-second at 7.5 i.p.s. or 15,000 cycles at 15 i.p.s. (i.p.s. = inches per second). Tape machines were getting very popular in the 1950s as prices came down and quality went up. Through the 1970s, just about every issue of electronics hobby magazine...

3D-Printed Antenna Designs Reduce Cost, Weight and Size

3D-Printed Antenna Designs Reduce Cost, Weight and Size - RF Cafe"U.S. Naval Research Laboratory (NRL) experts created and tested 3D-printed antennas and arrays to advance radar technology and enable new applications for the U.S. Navy. The lightweight and rapid production of 3D-printed parts make it an attractive alternative to traditional manufacturing that often requires expensive materials and specialized equipment. Radar systems perform critical functions for the Navy and remain an important part of maritime navigation and national defense. Parts for antennas and arrays, which are multiple connected antennas working together as one, may unexpectedly break or wear out, requiring replacement. Traditionally, parts are ordered or intricately machined out of metal, sometimes taking weeks to produce. 3D-printed radar parts, such as a cylindrical array, which provide 360-degree visibility..."

Many Thanks to IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products (IPP) has over 30 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. Please take a couple minutes to visit their website and see how IPP can help you today.

Improving Transmit / Receive Test Accuracy and Throughput

Improving Transmit/Receive Module Test Accuracy and Throughput - RF Cafe"Phased arrays have been used in radar applications for many decades. Recent trends are driving their adoption into other applications such as Electronic Warfare (EW), satellite systems, and even 5G communications. There are several new component technologies that are driving this migration: multiple transmit / receive (T/R) modules on a chip, higher-performance PCB laminates, and the acceptance of GaN as a power amplifier (PA) semiconductor process. Characterizing a T/R module places a high demand on a test system's performance and flexibility. The test system needs to support a variety of test modes while maintaining accuracy and constantly improving throughput. In many cases, it must measure high output power while at the same time delivering very low, highly accurate stimulus power. The system must provide intermodulation measurements..."

Hytron Corporation Advertisement

Hytron Corporation Advertisement, June 1944 QST - RF CafeHere is an advertisement for Hytron Corporation that I scanned from page 83 of my copy of the June 1944 QST magazine. Hytron was a manufacturer of electron tubes. "So Many Owe So Much To So Few," reds the title line. That is a paraphrase of Winston Churchill's famous statement during World War II, "Never in the field of human conflict was so much owed by so many to so few." That was in August 21, 1940, more than a year before the U.S. entered the war. Perhaps of greater interest to RF Cafe visitors are the next lines: "In peace, the Nation's debt to the radio amateur was great. During hurricanes, floods, and other disasters, he sprang forward with emergency communications. His endless hours of patient experimentations - particularly on the high and ultrahigh frequencies - helped open up, as if by magic, whole new segments of the radio spectrum...

Please Visit Empower RF's Website in Appreciation of Their Support

Empower RF Systems - RF CafeEmpower RF Systems is a global leader in power amplifier solutions. Empower RF Systems is an established and technologically superior supplier of high power solid state RF & microwave amplifiers. Our offerings include modules, intelligent rack-mount amplifiers, and multi-function RF Power Amplifier solutions to 6 GHz in broadband and band specific designs. Output power combinations range from tens of watts to multi-kilowatts. Unprecedented size, weight and power reduction of our amplifiers is superior to anything in the market at similar frequencies and power levels.

Monday the 26th

Bell Telephone Laboratories

Bell Telephone Laboratories, August 1952 Radio & Television News - RF CafeThis 1952-era promotion for Bell Telephone Laboratories describes what is essentially an early Supervisory Control and Data Acquisition (SCADA) system; it's just that the term had not been coined yet. SCADA systems uses sensors of various types to monitor the status of critical parameters and report it back to a remote location via telephone, cable, or radio links. It reduces or eliminates the need for personnel to be present unless immediate human interaction is required to handle an adverse situation. Electrical distribution stations, gas and oil lines, telephone switching installations, etc. SCADA systems are typically monitored by computers and in most cases log events and initiate required actions; however in some scenarios a human monitors the SCADA information and control processes manually. Nowadays, most people probably control their own personal SCADA systems via their smartphones or other Web connected devices. Your remotely controlled webcams...

U.S. Tech Salaries Climb in 2020

U.S. Tech Salaries Climb in 2020 - RF Cafe"The average increase in U.S. tech salaries of 3.6% between late 2019 and late 2020 may not sound dramatic. But compared with recent trends in tech salaries, it's a significant jump - especially considering the complicating factor of the COVID-19 pandemic and its attendant spike in remote work and office routine disruption. The increase is also particularly notable after 2017, 2018, and 2019 brought annual increases of less than a percent. This 3.6 increase - for an average total of $97,859 - is the number job search firm Dice found when it surveyed 9,143 job seekers between 29 September and 9 December 2020. The company runs a survey annually, generally getting around 10,000 responses..."

Career & Talent Opportunities at ARRL

Career and Talent Opportunities at ARRL - RF Cafe"The digital transformation at ARRL is under way! A significant commitment of talent and investment is being made to develop a dynamic and responsive digital enterprise in areas of amateur radio innovation and member engagement. This initiative is opening opportunities for experienced amateur radio enthusiasts to make ARRL the next stop in their careers. 'ARRL is where vocation and avocation collide,' said ARRL CEO David Minster, NA2AA. 'We are looking for people with passion, energy, drive, and talent to take ARRL to the next level.' Opportunities are on the ARRL website at www.arrl.org/careers. Both technical and non-technical positions are available now, with more on the horizon. 'Not only are there full-time positions available, but we will also occasionally be posting consulting or contract opportunities, as we are now for an IT project,' Minster said. If you have amateur radio experience and a desire to work at ARRL, apply for one of the positions listed online..."

Among the Novice Hams

Among the Novice Hams, November 1957 Popular Electronics - RF CafeAs with on my Airplane and Rockets hobby website, a big part of my motivation for scanning and posting these vintage electronics magazine articles has been two-fold. The primary purpose is to provide access to historical documents for research and educational reasons. The second reason is to have the names of people and places published in text format (everything OCRed) so that someone doing a Web search for himself, a relative, or a friend, might run across it here. I receive e-mails occasionally from readers who are thrilled to find those names in an old article, especially when the person discovered has passed on and it serves as a fond remembrance. Features such as this "Among Novice Hams" - a regular column in Popular Electronics magazine of the era - is a great place for finding them.

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!

Sunday the 25th

Technology Theme Crossword Puzzle for April 25th

Technology Theme Crossword Puzzle for April 25th, 2021 - RF CafeThis Technology Theme Crossword Puzzle for April 25th has many words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects. As always, this crossword 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!

Friday the 23rd

Ziff-Davis Electronic Laboratories

Ziff-Davis Electronic Laboratories, January 1940 Radio News - RF CafeJudging by some of the letters written to magazines by their readers, obtaining parts referenced in many construction articles proved difficult or impossible to procure. Ziff-Davis, a major publisher in 1940 as well as today, ran this notice in a 1940 issue of its Radio News magazine offering advice as to how one might go about getting everything needed. Unlike nowadays where nearly every available source worldwide can be found on the World Wide Web, back then searching could be - and too often was - a long, slow process. Just finding a phone number or mailing address for a potential supplier presented a major obstacle to anyone without a collection of catalogs and magazines - or at least knowing someone who did. Imagine needing ten non-standard parts and having to write letters to manufacturers and/or distributors trying to located critical component...

Super-Thin Element Offers "Positive" Potential for Transparent Electronics

Super-Thin Element Offers "Positive" Potential for Transparent Electronics - RF Cafe"Researchers from the Royal Melbourne Institute of Technology (RMIT) have introduced an ultra-thin material for semiconductors that could lead to transparent electronics. A molten mixture of tellurium and selenium, rolled over a surface, results in the deposit of an atomically-thin sheet of beta-tellurite. As a rare "p-type" semiconductor material, the beta-tellurite transports positively charged constructs known as holes. 'This new, high-mobility p-type oxide fills a crucial gap in the materials spectrum to enable fast, transparent circuits,' said team leader Dr. Torben Daeneke. The RMIT team's new p-type semiconductor is ten to one hundred times faster than existing p-type oxide semiconductors. according to the project's team leader. 'In our advance, the missing link was finding the right, 'positive' approach'..."

Anatech Electronics April 2021 Newsletter

Anatech Electronics April 2021 Newsletter - RF Cafe"Sam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his April 2021 newsletter that features his short op−ed entitled "A Wall of Interference!" The allusion is to the "wall" of antennas that typically comprises cell tower installations. Each antenna represents a source of potential signal interference for collocated antennas' receivers whose connected front end low noise amplifiers must successfully reject out-of-band signals and/or the inbound spurious mixer products generated by out-of-band signals. Sam also presents some relevant industry news items as well..."

Electronic Speed Mail

Electronic Speed Mail, April 1961 Popular Electronics - RF CafeElectronic mail did not start out as we know it today, whereby anyone with access to an Internet-connected device can compose and send a typed message to a similarly equipped receiver. The first electronic mail message was sent (and received) on November 1, 1960, between post offices in Washington, D.C., and Chicago, Illinois. This article from Popular Electronics magazine takes you on a step-by-step tour of how the Speed Mail system worked, including its dedicated shortwave radio links between participating cities. Great care was taken in an attempt to assure message confidentiality by having the letter opened and scanned automatically inside a sealed machine on the transmit end and then printed and placed in a sealed envelope on the receive end. Knowing what we know now about government snooping...

Many Thanks to Res-Net Microwave for Continuing Support!

Res-Net Microwave Components - RF CafeRes-Net Microwave has a complete line of precision RF & microwave components including attenuators, terminations, resistors, and diode detectors for commercial, military, and space applications. Products range from the small flange type to large 2,000 watt connectorized power attenuators and/or terminations at frequencies up to 26.5 GHz. In-house photo etch and laser trim capability. The company is a leader in development and production of the films required for these type of RF/microwave components. Please check out Res-Net Microwave's website to see how they can help with your current project.

Thursday the 22nd

First Phone Broadcast

First Phone Broadcast, January 1947 Radio-Craft - RF CafeAfter having read many articles about Dr. Lee de Forest, it seems the poor guy was besieged his entire life by envious and/or belligerent electronic communications compatriots who sought to defame him and/or deny him of monetary rewards. This January 1947 issue of Radio-Craft magazine includes a dozen or so pieces written by friends and colleagues who recognized the momentous struggles and achievements of Dr. de Forest. Such burdens of fame are borne by many - if not all - persons of similar celebrity. Dogged persistence is the order of the day for experimenters and breakers-through of assumedly impenetrable walls. Guys like de Forest lived by the old adage recommending that "if at first you don't succeed, try, try again." You'll be amazed at how de Forest whipped - almost literally - that thing which was preventing his wireless telephone from working. BTW, as I've pointed out before, you will find the good doctor's last name written as "de Forest, DeForest, and De Forest." As evidenced by his signature...

Modelithics® Releases the Qorvo® GaN Library v21.4.5

Modelithics® Releases the Qorvo® GaN Library v21.4.5Modelithics is pleased to announce the release of version 21.4.5 of the Modelithics Qorvo GaN Library for use with Keysight Technologies' Advanced Design System and Cadence AWR Design Environment. Version 21.4.5 of the Modelithics Qorvo Gallium Nitride (GaN) Library includes a total of 82 models containing 59 packaged power models, 17 GaN die power transistor products and 6 small-signal models. This release offers a non-linear model for the Qorvo QPD1028L, a 750W (P3dB) discrete GaN on SiC HEMT using Qorvo's QGaN50HV process. This device comes in an NI-780 package (eared). The Angelov-based large-signal model includes an advanced model feature for enabling intrinsic I-V sensing and is valid for Class AB operations...

Programmable ICs Secured by Chaos

Programmable ICs Secured by Chaos - RF CafeAt first I thought this was a news item about Maxwell Smart's archenemy. "A complex network of randomly interconnected logic gates creates conditions that could thwart hackers. Not all chaos is bad. In the case of programmable chips, chaos can be harnessed to create a unique digital identifier. Think of it as a fingerprint—only, instead of distinctive loops and whorls on human skin, this is about the unique physical variations present in silicon chips. These minute differences, often at an atomic level, vary from chip to chip, even if they are manufactured together. The physical variations can be amplified using a technology called physically unclonable functions (PUFs) to create a signature that is unique to a specific chip..."

Hobnobbing with Harbaugh - Those Happy Happy Hams

Hobnobbing with Harbaugh, November 1963 Popular Electronics - RF CafeHere is a little electronics hobbyist humor in the form a comic series titled "Hobnobbing with Harbaugh," compliments of Popular Electronics magazine. Dave Harbaugh drew many comics for technical magazines. For the non-Ham, QSL is the Q-code for "'I confirm that I received your transmission." You don't need to be an amateur radio operator to appreciate these comic strips, though. Note that with it being 1963, the husband and wife are shown sleeping in separate beds - just like in the TV shows of the era like The Dick Van Dyke Show and I Love Lucy. BTW, the kid in the crib is spelling out -..(d) .-(a) -..(d) -..(d) -.--(y).

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! 

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

Homepage Archive Pages

2024:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2023:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2022:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2021:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2020:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2019:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2018:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2017:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2016:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2015:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2014:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2013:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2012:  1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 (no archives before 2012)

Exodus Advanced Communications Best in Class RF Amplifier SSPAs - RF Cafe

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024


    Kirt Blattenberger,


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

Copyright  1996 - 2026

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website: AirplanesAndRockets.com

My Daughter's Website: EquineKingdom


Innovative Power Products Passive RF Products - RF Cafe

Amplifier Solutions Corporation (ASC) - RF Cafe