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Homepage Archive - March 2022 (page 3)

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

Tuesday the 22nd

Developments in Solid Dielectric R.F. Transmission Lines

Developments in Solid Dielectric R.F. Transmission Lines, October 1946 Radio News Article - RF CafeOne of the many advances in radio technology during World War II - transmission lines - is reported on here in a 1952 issue of Radio & Television News magazine. If you are less than maybe 30 years old there is a good chance the only kind of RF transmission line you have ever been exposed to is coaxial cable. I say 30 years old because by the early 1990s the majority of homes had either cable TV service or rooftop TV antenna lead-ins were using 75 Ω coaxial cable rather than the traditional 300 Ω twin lead (with the assistance of an impedance transformer at the antenna end). Author R.C. Graham rightly credits an efficient method of high-volume commercial polyethylene for use as a dielectric both for twin lead and coaxial cable. Prior to that some compound of rubber or steatite (had not heard of it, aka soapstone) was commonly used. If you are researching the history of RF transmission lines, this article will be a valuable collection of information...

SMA Connector Thumbwheel by Marki Microwave

SMA Connector Thumbwheel by Marki Microwave - RF CafeOver the years, many companies have offered "thumbwheel" type devices for sliding over SMA and other connector types to make screwing cables, adapters, attenuators, etc., on and off more convenient - especially in tight quarters. Says Marki Microwave, "Thumbwheels provide a wrenchless method of quickly torquing down RF/microwave test equipment. Thumbwheels are mounted around the male jacket of all standard RF connectors and adapters. They are secured with 3 0.050" hex screws providing a friction based grip for securing male connectors." You can't always just "Put the wrench away" as the PDF file suggests, since sometimes a properly torqued connection is essential, but for lab work you can't beat them. Unlike many "thumbscrews" that have an escape slot for slipping on and off over cable, these have no slot. Often these gadgets are handed out at trade shows, but if you ask nicely, you might get Marki to send you one as a promotional gift.

Power Ratings & Intermodulation Tests

Power Ratings & Intermodulation Tests, November 1960 Electronics World - RF CafeAlthough this article discusses audio waveform measurements, the lesson learned applies equally well to any waveform frequency. In the RF realm, we are accustomed to injecting two sinewaves at equal amplitudes into a unit under test (UUT) and reading the relative output powers of the two input signals and the n-order intermodulation signals. It is usually a very simple test with simple to interpret results handily shown on the display of a spectrum analyzer. The task is made a bit more difficult when injecting signals of unequal strengths and especially when measuring in units of voltage as a viewed on an oscilloscope display. I dare say most of us need to do some head scratching and looking up of formulas to pull off such a measurement...

Please Visit Triad RF Systems to Thank Them for Their Support

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

PMI Intros Monopulse Comparator

Planar Monolithic Industries (PMI) Intros Monopulse Comparator - RF CafePlanar Monolithic Industries (PMI), a leading supplier of custom, high-reliability MIC/MMIC components and subsystems for applications in space, military, communications, commercial and consumer electronics systems for more than three decades, recently introduced. PMI is proud to introduce model PMC-9D5G10D5G-7D6-SFF is a Monopulse Comparator operating over the 9.5 to 10.5 GHz frequency range. This model offers a maximum 7.6 dB insertion loss while maintaining a maximum amplitude balance of ±0.5 dB; a maximum phase balance of ±5°, isolation of 20 dB, VSWR of 1.5:1, and Average Power Handling of 10 W. Housing is 3.48" x 3.48" x 0.43" and has SMA Female Connectors. . Contact PMI today for more information.. Contact PMI today for more information...

Vintage Newark Electric Company Advertise c1946

Newark Electric Company, Inc., November 1946 Radio-Craft - RF CafeAround since 1934, Newark Electric is one of the longest-surviving electronic component mail order businesses. In the days before Digi−Key (founded in 1972), Newark was my go-to source for parts I needed ASAP. Allied Electronics (earlier Allied Radio), around since 1928, was my second choice. There was no Internet, so the fastest service was had by calling in your order - while paying a long-distance toll. U.S. Post Office and United Postal Service (UPS, since 1907; my Uncle Brian drove their trucks from Buffalo to/from Cleveland for 40 years) were the two prime delivery service of the era (FedEx came online in 1973). Reportedly, its first paper-format catalog was mailed out in 1948, two years after this full-page ad appeared in Radio−Craft magazine. Newark now goes by the name of Newark element14 (the 14th element in the periodic table happens to be silicon). The "About Us" webpage shows Newark and Newark element14 (in Asia) as being Avnet companies. In 1946 there were many hometown electronics parts outlets that included repair shops, hardware stores, and department stores, so much of what a person needed was available locally...

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

Sponsor RF Cafe for as Little as $40 per Month - RF CafeNew Scheme rotates all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000 website visits each weekday. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 12,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. I also re-broadcast homepage items on LinkedIn. If you need your company news to be seen, RF Cafe is the place to be.

Many Thanks to Aegis Power Systems for Their Continued Support!

Aegis Power Systems - RF CafeAegis Power Systems is a leading supplier of AC-DC and DC-DC power supplies for custom and special applications. Aegis has been designing and building highly reliable custom power supplies since 1995. They offer a complete line of switch mode power supplies and power converters for a variety of markets including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft, EV, telecom, and embedded computing applications. Design and manufacture of custom power supply solutions to meet each customer's exacting specifications. Please visit Aegis Power Systems today.

Monday the 21st

Nazis Are Warned to Shun Foreign Radio

Nazis Are Warned to Shun Foreign Radio, November 1939, Radio-Craft - RF CafeThis 1939 news bit from Nazi Germany overlords illustrates the results of well-meaning citizens voluntarily surrendering their personal freedoms and right to self defense. Nazi Party, by the way, derives from "National Socialist German Workers' Party." Remember that when someone with Socialist leanings these days calls you a Nazi. The 1st Amendment of the U.S. Constitution guarantees we, the American people, a right to free speech, and by extension, a right to listen to whatever someone else opts to say (excluding, of course, overt and specific threats of harm). Many generations have enjoyed that and a specific list of other freedoms, but the passage of time has seen a dilution of those freedoms due to aggressive lawmakers and judges, and the passive acceptance of it by too many citizens. Throughout history when citizens yielded their freedoms to government in promise of benefits, favors, protection, etc., they almost always found themselves on the business end of a gun (or tank, arrow, battering ram, sword, etc.) being wielded by that same "benevolent" government. America's founding fathers were so aware of the repeating pattern that they wrote the 2nd Amendment into our Constitution specifically to ensure "the governed" had means...

Tales from an Engineer's Life #172

Tales from an Engineer's Life #172: Tips on Self-Rescue from Hotel Bathrooms - RF CafeThis is a must-read -- "Tales from an Engineer's Life #172: Tips on Self-Rescue from Hotel Bathrooms." Lee Goldberg writes on the Electronic Design website of an amazing experience he had while attempting to free himself from a hotel bathroom whose doorknob failed to work. He alludes to Angus MacGyver, famous for his weekly TV show escapes and escapades at the hands of bad guys. Like his hero would have done, Mr. Goldberg decided upon a non-violent approach to the situation. Personally, there were times when I thought "Mac" would have been justified in just shooting a villain, but the scriptwriters thought it might tarnish his nice-guy persona. Anyway, enjoy the saga...

Aboard a Radar Picket Plane

Aboard a Radar Picket Plane, June 1956 Popular Electronics - RF CafeAlthough obviously (but getting less so) before my time, the mention of this airborne radar surveillance system having been built by General Electric, in Utica, New York, struck a chord since that is where I had my first engineering job after having graduated from the University of Vermont with a BSEE degree. It seems to me the work at the time was all done in the converted textile complex on Broad Street. They were the glory days of GE, Westinghouse, Collins, Raytheon, and other electronics titans whose engineers, technicians, assemblers, and program managers changed the world. The airplanes and equipment used here were precursors to our modern E-2 and E-3 fleet. 1956 must have been a big year for the General Electric plant in Utica, New York, where I had my first engineering job right out of college...

RF & Electronics Symbols for Visio

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

Many Thanks to Berkeley Nucleonics for Continued Support!

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

Sunday the 20th

Electrical Engineering Theme Crossword for March 20th

Electrical Engineering Theme Crossword Puzzle for March 20th, 2022 - RF CafeHere is your custom made Electrical Engineering theme crossword puzzle for March 20th, 2022. 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 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!

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

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 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 Amplifier Solutions Corporation (ASC) for Continuing Support!

Amplifier Solutions Corporation (ASC) - RF Cafe ASC designs and manufactures hybrid, surface mount flange, open carrier and connectorized amplifiers for low, medium and high power applications using gallium nitride (GaN), gallium arsenide (GaAs) and silicon (Si) transistor technologies. ASC's thick film designs operate in the frequency range of 300 kHz to 6 GHz. ASC offers thin film designs that operate up to 20 GHz.

Friday the 18th

Remington Rand Univac Computer

Remington Rand Univac Computer, May 1956 Radio-Electronics - RF CafeI tried with no success using an online translator to figure out what that line of Chinese writing is in this Remington Rand UNIVAC computer advertisement which appeared in a 1953 issue of Radio-Electronics magazine. If you can do the translation, please send me an e-mail and I will add it to this page. As a historical note, Remington is the company that made not only typewrites, but also the line of firearms and ammunition bearing that name. The first UNIVAC (UNIVersal Automatic Computer) computer was commissioned in 1951. Its main memory consisted of liquid mercury delay lines arranged in 1000 words of 12 alphanumeric characters each. Ironically, the speed and capability of the UNIVAC compared to the abacus in this ad is probably about the same as that of a modern supercomputer compared to the UNIVAC. A decade or so from now, we'll be making the same comparison between today's computers and quantum computers...

Tiny Switches Give SS LiDAR Record Resolution

Tiny Switches Give SS LiDAR Record Resolution - RF Cafe"When Google unveiled its first autonomous cars in 2010, the spinning cylinder mounted on the roofs really stood out. It was the vehicle's light detection and ranging (LiDAR) system, which worked like light-based radar. Together with cameras and radar, LiDAR mapped the environment to help these cars avoid obstacles and drive safely. Since a then, inexpensive, chip-based cameras and radar systems have moved into the mainstream for collision avoidance and autonomous highway driving. Yet, LiDAR navigation systems remain unwieldy mechanical devices that cost thousands of dollars. That may be about to change, thanks to a new type of high-resolution LiDAR chip developed by Ming Wu, professor of electrical engineering and computer sciences and co-director of the Berkeley Sensor and Actuator Center at the University of California, Berkeley. Wu's LiDAR is based on a focal plane switch array (FPSA), a semiconductor-based matrix of antennas..."

CTI's 515−T Electronics Slide Rule

515T Electronics Slide Rule, August 1967 Electronics World - RF Cafe, August 1967 Electronics World - RF CafeIt wasn't until February 1, 1972, that Hewlett-Packard introduced its HP-35 electronic calculator. Before that, when you spoke of an electronics calculator it referred to a computer (likely a vacuum tube type), a human who specialized in electronics calculations (as NASA and universities referred to them), or this special slide rule sold by Cleveland Electronics Institute - the 515−T. It had special scales for calculating reactance, and resonance, and had common circuit analysis formulas printed on the back side, and also came with an extensive user's manual. This full-page advertisement appeared in a 1967 issue of Electronics World magazine...

ConductRF Hand Reformable 50 Ω RF Coaxial Cables

ConductRF Hand Reformable 50 Ω RF Coaxial Cables at Digi-Key - RF CafeConductRF Hand-Reformable RF Coaxial Cables are available off the shelf from DigiKey. ConductRF FM series of Hand Formable RF cable assemblies provides system designers with a versatile solution that allows RF cables to be physically routed and set in to position during installation. Standard lengths and connector types feature performance up to 40 GHz. Low loss, tinned braided cable of 0.086" diameter with shielding of >100 dB. 100% factory tested for VSWR & insertion loss. RoHS & Reach compliant. Ideal for internal module linking and great for RF Testing. Made in the USA!

Playback Preamp for Stereo Tapes

Playback Preamp for Stereo Tapes, April 1958 Radio-Electronics - RF CafeHmmmm.... at the time I marked this stereo preamp project for posting I must have had a really good reason for it, but now I can't recall what that really good reason was. Maybe it was simply to mark the point in time when stereophonic electronic equipment was just beginning to be mainstream. Oh well, somebody somewhere will do a Google search on the topic someday and will be elated to find this. Besides, even though the use of vacuum tubes and magnetic tape is way outdated, there is a discussion of hi−fi audio that is still relevant. The article appeared in a 1958 issue of Radio−Electronics magazine. Thanks for your indulgence...

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

Sponsor RF Cafe for as Little as $40 per Month - RF CafeNew Scheme rotates all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000 website visits each weekday. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 12,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. I also re-broadcast homepage items on LinkedIn. If you need your company news to be seen, RF Cafe is the place to be.

Many Thanks to Exodus Advanced Communications for Their 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.

Thursday the 17th

Radio-Electronics Monthly Review

Radio-Electronics Monthly Review, November 1946 Radio-Craft - RF CafeFor many years in the late 1940s / early 1950s, Radio-Craft magazine ran a regular "Radio-Electronics Monthly Review" feature that reported on industry news items. This May 1947 issue included such topics as the post-war discovery of German "teletypers" which used a series of electrical impulses to form the numerals, letters, and symbols by constructing them using vertical and horizontal lines. Doing so enabled symbols other than a standard character set to be transmitted and received. It also made the receiver/printer apparatus more compact since it only needed a few shapes for impressing the image. Also reported was the fact that radar development cost more overall than the cost of developing the atom bomb. In some ways that is surprising, in other ways not. Cosmic rays and "other mysterious energy radiations" were determined to be interfering with high altitude radio communications. Read on for more interesting tidbits...

Magnetism Helps Electrons Vanish in High-Temp Superconductors

Magnetism Helps Electrons Vanish in High-Temp Superconductors - RF Cafe "Super-conductors - metals in which electricity flows without resistance - hold promise as the defining material of the near future, according to physicist Brad Ramshaw, and are already used in medical imaging machines, drug discovery research and quantum computers being built by Google and IBM. However, the super-low temperatures conventional superconductors need to function - a few degrees above absolute zero - make them too expensive for wide use. In their quest to find more useful superconductors, Ramshaw, the Dick & Dale Reis Johnson Assistant Professor of physics in the College of Arts and Sciences (A&S), and colleagues have discovered that magnetism is key to understanding the behavior of electrons in 'high-temperature' superconductors. With this finding, they've solved a 30-year-old mystery surrounding this class of superconductors, which function at much higher temperatures, greater than 100 degrees above absolute zero. Their paper, 'Fermi Surface Transformation at the Pseudogap Critical Point of a Cuprate Superconductor,' published..."

Selecting and Using Pulse Generators

Selecting and Using Pulse Generators, May 1967 Electronics World - RF CafeSome things never change, and the basic definition of a pulse waveform is one of them. This article form the May 1967 edition of Electronics World magazine does a nice job of defining the fundamental characteristics of a pulse, including rise and fall times, overshoot, pulse width, etc. Ham shacks and company labs alike are still stocked with the venerable HP 215A and HP 213B signal generators that appear in this piece. If you're lucky, you can get a good deal on them from someone on eBay...

Anatech Electronics March 2022 Newsletter

Anatech Electronics March 2022 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his March 2022 newsletter that features his short op−ed entitled "Will CBRS Private Networks Take Off?," where he discusses the pros and cons of moving to the Citizens Broadband Radio Service licensed frequency band (which means paying a usage fee) versus remaining in the licensee-free Wi-Fi spectrum. According to Sam, benefits include greater security, less interference, and lower latency for real-time processes. The biggest negative (other than having to pay for it) is the relatively narrow bandwidth that can limit data rates. CBRS private networks are only now being deployed...

Let's Keep It Simple - Adjusting the Novice Antenna

Let's Keep It Simple - Adjusting the Novice Antenna, September 1953 QST - RF CafeIf you have a copy of EZNEC software (now a free download), you can try modeling an end-fed "sky wire" antenna like the one described in this article and see how it functions when driven from a location high above terra firma when the transmitter and receiver are connected to Earth ground via some sort of wire. Author Norman Rowe operated from his attic as did (and still do) many Hams. Although almost any reasonable mismatch can be accommodated with a proper matching circuit, that has no major bearing on what the antenna radiation pattern looks like. However, the characteristics of the ground circuit most certainly affects the antenna pattern. Surely someone like ARRL's Joel Hallas (W1ZR, SK), an EZNEC master, could answer that without even having to run a simulation. Come to think of it, I really don't know what a serious mismatch does to the power factor of the voltage and current flowing in the antenna itself. Does the relative phase of current and voltage always automatically correct itself in the antenna? If not...

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 Welcome Lotus Communications Systems as an RF Cafe Supporter!

Lotus Communication Systems Modular RF/Microwave Components - RF CafeLotus Communication Systems supplies custom, high reliability RF/Microwave modules, IMA, and subsystems for application in Space, Satellite, Communications, Commercial, and Consumer electronic systems. Lotus provides custom solutions for general RF/Microwave industry, GPS/GNSS industry, Test Instrument and other application specific markets. Each of our RF/microwave module/IMA/Subsystem meet our exceedingly high standards of quality, and are 100% MADE IN USA. Our RF/microwave products cover frequency band up to 64 GHz and include RF Amplifiers (LNA, MPA, PA), Bias Network, Frequency Translator (Frequency Mixer, Multiplier, Divider, Block up/down converter), Frequency Source (OCXO, TCXO), Passive (Coupler, Attenuator, Filter, Divider), RF Limiter and USB Programmable RF modules (Digital Attenuator, Signal Generator and Block Up/Down Converter).

Wednesday the 16th

The Elements of Teleducation

The Elements of Teleducation, May 1956 Radio-Electronics - RF CafeAs with most things technical, Hugo Gernsback, editor of Radio-Electronics magazine, was ahead of the curve when he wrote of remote classrooms (Teleducation, as Gernsback dubbed it) in this 1956 article. A big proponent of the Stratovision and MPATI systems which employed an airborne broadcast platform for providing instruction to classrooms across hundreds of miles. That was in the era predating satellites (Stratovision) and the point where satellites could be used for other than specifically designed purposes (MPATI). By 1956, though, transcontinental cable and microwave relay systems had been built that did facilitate widespread broadcasting. Many regions were still bypassed, but all major cities where universities and larger technical schools were located had the capability of one-way and two-way hookups to a teaching node...

The "G-Line" Community TV System

The "G-Line" Community TV System, November 1956 Radio & Television News - RF CafeWhen I first saw this article on the "G-Line" transmission system, I thought the cone at each end of the line was just a gimmick to make it look high-tech. My ignorance of the way the system works was responsible. As it turns out, the "G-line" transmission medium, named after inventor Dr. Georg Goubau, an engineer at the renowned U.S. Army Signal Corps Engineering Laboratories at Fort Monmouth, NJ, used the cone to transition a finite radius coaxial cable outer conductor to an infinite radius, sort of virtual, outer conductor that was free space. Doing so permitted a single line to do the job of carrying a signal from point A to point B. This significantly reduced the installation and maintenance cost of deploying a cable-based communications system - in this case for television broadcasts in areas where over-the-air broadcasts were nearly impossible. G-line came with many of its own unique issues, and history shows that ultimately it was not a workable long-term solution...

PDP-11: The Most Influential Minicomputer of All Time

PDP-11: The Most Influential Minicomputer of All Time - RF Cafe"It helped popularize the interactive computing paradigm we take for granted today. The history of computing could arguably be divided into three eras: that of mainframes, minicomputers, and microcomputers. Minicomputers provided an important bridge between the first mainframes and the ubiquitous micros of today. This is the story of the PDP-11, the most influential and successful minicomputer ever. In their moment, minicomputers were used in a variety of applications. They served as communications controllers, instrument controllers, large system pre-processors, desk calculators, and real-time data acquisition handlers. But they also laid the foundation for significant hardware architecture advances and contributed greatly to modern operating systems, programming languages, and interactive computing as we know them today..."

Sr. RF Engineer / Electrical Engineer Wanted by Quaise Energy

Sr. RF Engineer / Sr. Electrical Engineer Wanted by Quaise Energy - RF CafeQuaise develops millimeter wave drilling systems for deep geothermal heat access. Our technology is the only approach in the world with the potential to build geothermal wells at unprecedented depths and temperatures. Quaise's technology consists of a source of millimeter wave (MMW) such as a gyrotron operating in continuous wave mode and at high power, to vaporize subsurface rock. Our gyrotron-powered drilling platform vaporizes boreholes through rock and provides access to deep geothermal heat without complex downhole equipment. Based on breakthrough fusion research and well-established drilling practices, we are developing a radical new approach to ultra-deep drilling. Quaise is seeking an accomplished electrical engineer or physicist with at least 5 years work experience. Specific discipline of study and/or work in radio frequency is required, preferably high power RF transmission over waveguide. Ideal candidate would have experience in both the RF and high voltage (20 kV+) field...

Electronic Crosswords from Electronics World

Electronic Crosswords, May 1967 Electronics World - RF CafeThis crossword puzzle appeared in the May 1967 edition of Electronics World. If you happen to be an avid cruciverbalist as am I, then you might want to try a few of the RF and microwave engineering themed crosswords that I have been publishing weekly for two decades. Unlike the RF Cafe crossword puzzles which contain only words and clues related to science and engineering, these ones which appeared in various electronics magazine sometimes use a common word to fill in where needed...

RF & Electronics Symbols for Visio

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

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.

Tuesday the 15th

Basic Color TV

Basic Color TV Part I, January 1954 Radio-Electronics - RF CafeFar more than electronics went into the development of color television. Extensive research into how human beings perceive color, combined with the color-producing ability of suitable chemical compounds ultimately determined how color picture tubes would be manufactured, and the electronic circuits which would activate them. Most people are not aware that the very earliest color television schemes were electromechanical contraptions that either spun a transparent color wheel in from of a modulated light beam, or used an oscillating mirror to direct colors to the appropriate position on a display screen. Fortunately, the fully electronic version won. Even so, there were retro-fit kits sold and installed to convert black and white (B&W) sets to color using the spinning color wheel system (upper left). As recently as the late 1960s there were commercials selling a screen to place over the front of your B&W set that was tinted green at the bottom, red in the middle, and blue at the top...

Recent Developments in Electronics

Recent Developments in Electronics, May 1967 Electronics World - RF CafeTalk about ESD tolerant! Get a load of that electron beam in the process of welding computer memory. Of course that isn't silicon - it's magnetic core memory, the kind with tiny toroids with four extremely small gauge wires running through them for the read and write operations. If you want a computer memory that will survive a nuclear EMP, this is your answer. Hook it up to your electron tube computer and you'll be playing Pong* while all the other survivors are back to tic-tac-toe with pencil and paper! Also news in this 1967 issue of Electronics World magazine was final testing of the Tiros weather satellite, a million-volt pulse generator, and a multi-satellite military satellite payload being launches by the U.S. Air Force...

FM to AM Converter for Vintage Radios

FM to AM Converter for Vintage Radios - RF Cafe Cool ProductRF Cafe visitor Bob D. sent me information on this interesting device that allows owners of vintage AM radios to receive FM stations while using the original tuning dial to cover the entire 88-108 MHz band. Monsieur David Winter, of France, is the designer and seller of this FM Converter for Vintage Radios. Installation and calibration is not for the faint of heart, since it involves tapping directly into the circuitry and disconnecting some of the sections where the device inserts the signal into the audio frequency (AF) section, totally bypassing the RF and IF sections. A direct connection to the tuning capacitor is used to tune the module throughout the FM band, which is a primary feature of scheme. However, it requires the capacitor to be disconnected from all other circuitry to prevent normal voltages and impedances from adjacent connected components from entering the integrated circuit (IC). Retaining the AM reception (and possibly shortwave reception) function requires the installer to devise a custom switching scheme. It uses the 6.3 VAC vacuum tube (valve) heater supply. In older radios you need to be sure to locate a "real" ground (common) point to assure the voltage is properly referenced. The price is €29.90 ($32.83), which is currently the cost of 7-8 gallons of gasoline...

Aerial Antenna Test for Venus Mission

Aerial Antenna Test for Venus Mission - RF Cafe"How can you accurately test a space antenna down here on Earth when it has been scaled up to penetrate the subterranean depths of another planet? This was the question faced by SENER in Spain, currently designing a candidate antenna for ESA's EnVision mission, which will explore Venus from its inner core to outermost cloud layers. To solve it they lifted their prototype skyward with a balloon. 'To develop key technologies for future missions, ESA's Directorate of Technology, Engineering and Quality often explores multiple approaches,' explains ESA antenna engineer Paul Moseley. 'This includes parallel prototypes for EnVision's Subsurface Radar Sounder (SRS), which will transmit and receive radio signals to chart the Venusian subsurface. It will achieve this using very low frequencies (9 MHz) which in turn means its antenna has to be very large, 16 m across..."

Operate and Release Times of Relays

Operate and Release Times of Relays, April 1967 Electronics World - RF CafeThe April 1967 edition of Electronics World magazine had a series of articles about designing systems with electromechanical relays. Even in today's world of solid state relays, there are still lots of applications for electromechnical relays. Only a handful of American companies still make them. The application tutorials provided herein are as valuable to today's engineers and technicians as they were 55 years ago. This particular piece covers operate and release times of relays. Other articles in this issue include "Reed Relays, Time-Delay Relays," "Finding Relay Operate and Release Times," and "Arc, Surge, and Noise Suppression."

RF & Electronics Symbols for Visio

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

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.

   

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

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Exodus Advanced Communications Best in Class RF Amplifier SSPAs - RF Cafe
Windfreak Technologies Frequency Synthesizers - RF Cafe
RIGOL Technologies (test equipment) - RF Cafe
RF Electronics Shapes, Stencils for Office, Visio by RF Cafe
TotalTemp Technologies (Thermal Platforms) - RF Cafe

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About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024

Webmaster:

    Kirt Blattenberger,

    BSEE - KB3UON

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...

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