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Homepage Archive - April 2023 (page 3)

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

Friday the 21st

Quantum-Enhanced Microwave Ranging

Quantum-Enhanced Microwave Ranging - RF Cafe""A study published in Nature Communications highlights the progress made in practical quantum sensing by a team led by academician Guo Guangcan and Prof. Sun Fangwen from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS). The team utilized micro and nano quantum sensing, coupled with local electromagnetic field enhancement at deep sub-wavelength scales, to study the detection of microwave signals and wireless ranging, achieving a positioning accuracy of 10-4 wavelengths. Radar positioning technology based on microwave signal measurement is widely used in activities such as automatic driving, intelligent manufacturing, health monitoring, and geological exploration. In this study, the research team combined quantum sensing of solid-state systems with micro/nano resolution and deep subwavelength localization of electromagnetic fields to develop high-sensitivity microwave detection and high-precision microwave positioning technology..."

Carl and Jerry: Wired Wireless

Carl and Jerry: Wired Wireless, January 1962 Popular Electronics - RF CafeIn the continuing saga of Carl and Jerry, our two young electronics hobbyists visit a college radio station where the manager gives a tour while explaining the technical aspects of the equipment. RF bridges, hybrid junctions, oscillator coils and plate-tank pi-networks, cue amplifiers, limiter amplifiers, patch board, power supplies, and a lot of other terms that cause RF Cafe visitors to salivate are woven into the story. Carl and Jerry are surprised to learn that the transmitter output power is high enough that dormitory residents can pick up the signal with "only a pair of earphones clipped across a 1N34 diode" as well as with a standard AM radio. In fact, that's the whole point of the story because the broadcast is not over the air, but via the campus' AC electrical system - hence, "wired wireless..."

China Deals with Taliban on Lithium Mining

China Deals with Taliban on Lithium Mining - RF CafeTwo years after the U.S. abandoned Afghanistan in 2020 and left more than $60,000,000,000 worth of equipment in the Taliban's hands (and still some U.S. citizens trapped there), China is now planning to extract oil and minerals - including lithium from vast deposits. Now that the Taliban has banned girls from attending school, there will be plenty of labor available to wade through the artificially flooded plains created to process the lithium. That lithium will then go into everything from cellphones to electric cars. Since China still enjoys developing country status, they are free to generate as much pollution as required to bring them up to the living standards of privileged countries like America - like for instance in Chicago, Atlanta, and Los Angeles. What can possibly go wrong?

The "Light" Fantastic

The "Light" Fantastic, July 1963 Popular Electronics - RF Cafe"The boy and his father had just witnessed a demonstration of one of the most promising and fastest developing technological devices ever conceived by man - the laser. In only three whirlwind years, the laser - which gets its name from the initials of Light Amplification by Stimulated Emission of Radiation - has moved out of the theory stage, out of the laboratory curiosity category, and into a whole new, exciting world of applications." That's the opening of an article in the July 1963 edition of Popular Electronics. I remember when ruby lasers were the the rule rather than the exception for lasers. Power levels were measured in units of "Gillettes" in reference in the number of razor blades they could cut through. Next came chemical lasers with power levels in the megawatts and now even gigawatts that can take out ICBM warheads as they reenter the atmosphere and can fry orbiting satellites. At the same time the realm of semiconductors and microcircuits was turning out devices on the opposite scale for use in communications, inertial navigation, and boardroom presentation pointers. This article is an extensive recounting in layman's terms the state of the art in 1963...

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 - and don't miss the blog articles!

Thursday the 20th

Electronics-Themed Comics

Electronics-Themed Comics, April 1960 Radio-Electronics - RF CafeHmmmm, I'm not quite getting the comic on page 59, unless it's referring to the remoteness of the "customer." In 1960 when it appeared in Radio-Electronics magazine, some would have likely considered it scandalous. The editor probably justified the theme the way National Geographic did their jungle tribeswomen exposés (pun intended). I like the page 78 comic with the unique typeface used to represent the guy's hurt foot. In 1960, such characters would require hand-drawing or the special Dial-A-Type typewrite ball sold to enable direct typing onto paper. On page 118, what kind of clip is that? (get it?). 1960 was also the era of wireless remote control of everything, as implied in the page 128 comic. Enjoy.

Panoramic Reception

Panoramic Reception, March 1945 QST - RF Cafe"Technically, panoramic reception is defined as the simultaneous visual reception of a multiplicity of radio signals over a broad band of frequencies. In addition, panoramic reception provides an indication of the frequency, type and strength of signals picked up by the receiver. Deflections or 'peaks' appearing as inverted 'V's on the screen of a cathode-ray tube." It is the kind of display that radar operators at Pearl Harbor were using when they mistook wave of incoming Japanese bombers for a squadron of B-17s from the mainland. The panoramic receiver is not a wartime development, experimental models having been produced just prior to the outbreak of war. However, the many uses to which it has been put have demonstrated that the panoramic idea, particularly in the form of adaptors which may be connected to any receiver, is going to be very important and useful in the ham station of the future. In simple language this article reviews the general principles upon which the panoramic system is based and includes also a picture of the many ways...

FCC Launching Space Bureau

FCC Launching Space Bureau - RF Cafe"The Federal Communications Commission will officially launch its Space Bureau tomorrow, reflecting the agency's reorganization to deal with increased interest in satellite-based communications. Chairwoman Jessica Rosenworcel proposed the reorganization late last year and the Commission unanimously approved it in January. The change splits the International Bureau into two 'separate, cooperative units' within the FCC: The Space Bureau, which will focus on 'policy and licensing matters related to satellite and space-based communications and activities,' and Office of International Affairs (OIA), which will coordinate FCC work with foreign and international regulatory authorities. The FCC has already received applications for 64,000 new satellites, indicating just how much the sector is booming - particularly in the area of low-Earth orbit (LEO) satellites. In the coming years, tighter integration between 5G terrestrial and non-terrestrial networks is expected to emerge. Early use cases for smartphone-based satellite connectivity are already in play, such as T-Mobile US' deal with Starlink to share spectrum and provide ubiquitous text message communications, expected by the end of this year, and Apple's emergency SMS connectivity available in the iPhone 14 via service with GlobalStar's LEO network. In January, Qualcomm also announced its Snapdragon Satellite, a 5G modem-RF system which is designed to provide global..."

Grantline Models 605 & 606 Datasheet

Grantline Models 605, 606, November 1946 Radio News - RF CafeA schematic and parts list for the Grantline models 605 and 606 tabletop AM radios appeared in a 1946 issue of Radio News magazine. It is a 6-tuber with pushbutton tuning. Molded Bakelite housings were popular in the day because complex curves with a smooth surface could easily be accommodated, and usually a variety of colors were available. This white one appears on YouTube. A few pages from the Sams Photofact data packet showed up on eBay, so I did a screen capture of them for your convenience. There are still many people who restore and service these vintage radios, and often it can be difficult or impossible to find schematics and/or tuning information. A running list of all data sheets can be found...

RF & Electronics Symbols for Office™

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

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 19th

Low-Noise Broadcast Antenna

Noteworthy Circuit: Low-Noise Broadcast Antenna, March 1969 Radio-Electronics - RF CafeHaving only been seriously (somewhat) on the amateur radio scene since earning my Ham license in 2010, I previously did not pay a lot of attention to antenna construction and interconnection to radio gear. My experience was limited to routing 300 Ω twin-lead transmission line from the rooftop TV antenna down to the indoor set. I also made a lame attempt at stringing a long AM antenna wire in an attempt to pull in distant stations at night. It worked better than the built-in coil on the ferrite rod, but was nothing to brag about. Evidently, there was a better method than a single lead for an AM antenna. This 1969 Radio-Electronics magazine article suggests using a balun to create a balanced twin line from the wire antenna to the receiver, then a balun back to single line at the receiver end. Probably not many people are using such configurations anymore, but the subject was considered worthy of a page in a national publication in the day. Maybe there are still...

Anatech Electronics April 2023 Newsletter

Anatech Electronics April 2023 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his April 2023 newsletter that features his short op-ed entitled "Havana Syndrome: Case Closed," which discusses where the U.S. government recently declared their investigation into the mysterious neurological issues some foreign embassy staff had been reporting showed that use of a microwave emitter to induce maladies was "very unlikely." Keep in mind that conclusion was brought to you by the same type government jackbooted thugs who brought you "safe and effective" vaccines. Sam, as do I, believes just because government investigators have declared the "conspiracy theories" to be unfounded, it does not remove the possibility of radiation poisoning given the history of Communist regimes in not so long ago events. Russia and other countries were caught zapping personnel with microwaves on multiple occasions. Sam wrote about the Havana Syndrome back in 2019...

Light Emitting Diodes (LEDs)

Light Emitting Diodes (LEDs), November 1970 Popular Electronics - RF Cafe"One of the least known but most fascinating of semiconductor devices is the light-emitting diode (LED). Until quite recently, these devices were too expensive for widespread use." That statement is hard to imagine in 2023. It was written 50 years ago by Mr. Forest Mims, in this November 1970 issue of Popular Electronics magazine. Now, LEDs seem to be in every consumer device, whether it be a simple power ON indicator light or an array of alpha-numeric displays. TV and stereo remotes use infrared LEDs, opt isolators that use LEDs are integral components of modems, motor controllers, and motion sensors. Commercial truck and some passenger vehicle tail lights are made of LED clusters, as are the very expensive LED bulbs that are quickly replacing incandescent and, thankfully, the toxic (mercury) CFL household bulbs. What was once rare is now a commodity - it happens all the time...

7 Pillars of 5G/6G RF System Design

7 Pillars of 5G/6G RF System Design - RF Cafe"Designers of 5G/6G systems must take into account the seven major 'pillars' critical to their successful creation, which center around antennas, receivers, and RF power, among other key issues. In the Old Testament's Book of Proverbs, the first verse of the ninth chapter is simultaneously enigmatic and captivating: 'Wisdom has built her house; she has set up its seven pillars.' The verse has been referenced frequently and in a broad variety of ways over the centuries. Regardless of how interpretations of the verse may vary, all reflect an underlying understanding - that creative success requires planning, expertise, insight, inspiration, using the proper instruments, and above all, a commitment to achieve value that's both exceptional and unique. We can logically extend the above to any endeavor in High Technology, and particularly to one of the leading sectors for innovation at the chip, system, and software level: RF communication systems in 5G/6G. At the heart of these communications systems lies the physical layer, involving modulation, transmission, and demodulation of signal and data content..."

Cell Tower Deaths

Cell Tower Deaths (PBS Frontline) - RF CafeWhen a worker assembling cellphones in a plant in China hurls him/herself out of a window, it makes headlines. Like the human cost of extracting the minerals that go into making cellphone components, people yawn and write it off as the cost of progress. Among the many other dimensions of that cost is one that, until recently, received little attention - cell tower worker falls. According to a joint investigation by Frontline and ProPublica that was aired in May 2012, there is a well-established record of ill-equipped and ill-trained climbers who fall [pun intended] victim to low budget operations... and, to be honest, sometimes their own stupidity. Cell tower climbers experience 10x more on-the-job deaths as the average construction worker. That might seem logical and even expected given that you normally think of a construction worker as the guy banging nails in that new housing development down the road...

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 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! 

Tuesday the 18th

What's Your EQ (Electronics Quotient)?

What's Your EQ (Electronics Quotient)?, February 1967 Radio-Electronics - RF CafeYou will probably breeze through both of these "What's Your EQ?" circuit challenges in the February 1967 issue of Radio-Electronics magazine. Don't look too deeply into what is presented. Both require figuring the voltage between two points. For the Zener Limiting Circuit, just apply basic knowledge about zener diodes. The "Voltage Problem" circuit requires a simple summing of voltages around the single loop to derive the current, then calculate the voltage across R1 to get VB. VA is a no-brainer. The depiction of the DC sources is a bit wonky; the voltages shown are the totals for the each group of cells (aka battery), not per cell...

Light Modulation of Single-Molecule Electron Source

Light Modulation of Single-Molecule Electron Source - RF Cafe"Researchers at University of Tokyo, JTS PRESTO, Ludwig Maximilians Universität and Kindai University recently demonstrated the modulation of an electron source by applying laser light to a single fullerene molecule. Their study, featured in Physical Review Letters, could pave the way for the development of better performing computers and microscopic imaging devices. 'By irradiating a sharp metallic needle with femtosecond pulses, we had previously demonstrated optical control of electron emission sites on a scale of approximately 10 nm,' Hirofumi Yanagisawa, one of the researchers who carried out the study, told Phys.org. 'The optical control was achieved using plasmonic effects, but it was technically difficult to miniaturize such an electron source using the same principle. We were seeking a way to miniaturize the electron source and we hit upon the idea of using a single molecule and its molecular orbitals.' Yanagisawa and his colleagues set out to realize their idea experimentally using electrons emitted from molecules on a sharp metallic needle..."

The Truth About the Vertical Antenna

The Truth About the Vertical Antenna, May 1952 QST - RF CafeWhenever you see an article with "The Truth About..." in the title, the expectation is the author is going to reveal some aspect about the subject that has been kept from public knowledge by nefarious schemers, or a common misconception is going to be cleared up for the unwitting majority. This 1952 QST magazine article comes closest to the later category, although it is not really clear to me after reading it what the newly revealed "truth" is - maybe just that the effort required for using a vertical antenna at fairly long wavelengths is worth it because of low radiation angles that facilitate local area and relatively nearby communications. A lot of really good information is presented regarding vertical antenna field patterns, antenna installation, and feedline systems...

Electromagnetic Gun Fires Coins for Bullets

Electromagnetic Gun Fires Coins for Bullets - RF CafeThis story on the SCMP website reports on a new electromagnetic gun developed for riot control - which in China (and increasingly in the U.S.) means any group opposed to a government policy. It is a mostly peaceful gun in that it is purportedly designed to dissuade rather than injure or kill. Coin-shaped projectiles are electromagnetically accelerated like a high velocity rail gun and aircraft carrier catapult system. The quiet operation supposedly will invoke less panic, which really means more people will stick around and get shot rather than running away from the normal gunshot noise. If adopted in civilized Western countries, a synthesized loud bang noise will be required by an attached speaker akin to how electric cars are now being required to carry noise generators because they are so quiet that pedestrians get run down in the cities. Governments are always too smart by half.

Theory and Application of U.H.F.

Theory and Application of U.H.F., April 1945 Radio News - RF CafeNot having a full collection of magazines is a real disadvantage when multiple part stories are published and some editions are missing. Such is the case here with Milton Kiver's series on "Theory and Application of UHF" in Radio News magazine. I do have other parts of the series, but they have not been posted on RF Cafe yet. However, each installment is pretty much independent of the others. This month's topic is on the fundamental theory of electrical potential and force. The name "Maxwell" is mentioned, but not in the way that strikes fear in the heart of engineering students being introduced to the integral and differential forms of his eponymous equations (I know first-hand), so it's safe to keep reading. Gauss's Law get honorable mention as well. First semester physics books cover the same material, but since you might not have one handy, here you go...

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. 50 Ω and 75 Ω models are available, along with a full line of precision calibration and connector adaptors.

Monday the 17th

You Can Build These 16 Speaker Enclosures

You Can Build These 16 Speaker Enclosures, March 1969 Radio-Electronics - RF CafeBuilding speaker enclosures was a popular project for stereo enthusiasts in the 1969 time period when this article appeared in Radio-Electronics magazine. Lots of well-designed speakers were commercially available, but they tended to be expensive. High-end speaker enclosures typically had high-end speakers within, which contributed to the increased cost. I built a pair of wooden enclosures while in the USAF at Robins AFB, Georgia. It had a very nice woodshop. The speaker cabinets had a very simple internal design; the removable front frame was the hardest part to build. Mine were made from pine. For my level of music appreciation, I found that a quality set of car speakers provided great sound for all but the deepest bass frequencies. An added advantage was that the crossover circuit was built in, so all I needed was to build a crossover to split the really low frequencies to 10" bass speakers that were purchased at Radio Shack . The Radio Shack crossover circuits were too high (1 kHz) so I found an article showing how to build one that split at around 500 Hz; admittedly, it didn't work very well. The grille cloth also came from Radio Shack...

Electronic Charges Imaged with Single-Atom Resolution

Electronic Charges Imaged with Single-Atom Resolution - RF Cafe"Materials typically conduct electricity or insulate against it - so experimental and theoretical physicists have been captivated by a compound called samarium hexaboride (SmB6) that appears to do both. Numerous studies over the course of 50 years have revealed that SmB6 acts like an insulator as well as an electricity-conducting metal. Now, researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) say it's possible to image the exact position of electrons along the surface of SmB6 with single-atom precision, enabling a breakthrough in understanding the compound's properties and why it can both insulate and conduct. The findings, published in Science, build upon SEAS research reported in 2019 that determined that SmB6 is a topological insulator - meaning it conducts electricity along its surfaces but not its insides. Despite the 2019 discovery about SmB6's surface metallicity, many questions remained about its overall metallicity and why different measurements didn't generate consistent results..."

Do You Know Your Bipolar Transistors?

Do You Know Your Bipolar Transistors?, August 1973 Popular Electronics - RF CafeMr. Lothar Stern, of Motorola Semi, published a 3-part series on transistor theory in Popular Electronics magazine in 1973. This is part 1 (here is Part 2). By that time, transistors had pretty much replaced vacuum tubes in all new electronic products - if you don't count cathode ray tubes (CRTs) in televisions and some high power applications. Technical schools were still teaching about vacuum tubes since there was a still a lot of legacy equipment that needed to be maintained, and the main concentration had switched over to transistor theory. 1973, the year I turned 15, is right around the time I began seriously delving into the electrical and electronic realms as an eventual vocation. I distinctly remember being bewildered and amazed the first time I was told, in a USAF classroom, that a PN junction held to a fairly constant voltage (~0.7 V for silicon) regardless of the current through it - within the specified operational range...

Werbel Multi-Band Quad Coupler for 4-18 GHz

Werbel Microwave Multi-Band 8.5 dB Quad Coupler for 4 to 18 GHz - RF CafeWerbel Microwave, a designer and manufacturer of RF and microwave power couplers, dividers, terminations, and DAS equipment, introduces the model C-9001-8.5, a multi-output quad directional coupler that operates from 4 GHz to 18 GHz with four separate output bands. This totally unique approach offers the ability to filter different bands without the need of a power splitter, thereby reducing the path insertion loss. The product is customizable in terms of dB value(s) and multiplexed frequency bands. Werbel Microwave's catalog of directional couplers and power splitters / combiners are high performance at an affordable price point. Our original design, USA made...

Radio Aloft!

Radio Aloft!, September 1932 Radio News - RF Cafe"Don't forget who brung you to the dance," is a variation of the old adage that admonishes you to remember who/what it was that provided the opportunity to be where you are now. It aptly applies to radio communications of all sorts. This short article from a 1932 edition of Radio News discusses the advent of radio beacon installations across America to facilitate air navigation during inclement weather. Before there was a Federal Aviation Administration (FAA), the Department of Commerce handled commercial air traffic for passenger and cargo payloads. Aviation was on the verge of becoming a very profitable industry (the Douglas DC-3 would make that happen in 1935) and it was necessary to develop airspace controls to ensure safety and smooth operations. Early direction finding equipment used a directional loop antenna to indicate the bearing (not necessarily the heading, due to winds) to a ground-based broadcast station. Audible signals indicated whether the aircraft location was to the left or right of the station. Visual indicators would later provide course deviation information. Aside from GPS, radio beacon navigation is fundamentally the same today as it was in 1932, only with more precision, greater reliability, and more reference stations. If you don't know a VORTAC station when you see it...

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeNew Scheme rotates all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000 website visits each weekday. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 17,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. If you need your company news to be seen, RF Cafe is the place to be.

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.

Sunday the 16th

Electronics Theme Crossword Puzzle for April 16

Electronics Theme Crossword Puzzle for April 16, 2023 - RF CafeThis custom RF Cafe electronics-themed crossword puzzle for April 16th contains words and clues which pertain exclusively to the subjects of electronics, science, physics, mechanics, engineering, power distribution, astronomy, chemistry, etc. If you do see names of people or places, they are intimately related to the aforementioned areas of study. As always, you will find no references to numbnut movie stars or fashion designers. Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds of them dating back to the year 2000. Enjoy.

SpaceX to Launch Most Powerful Rocket Ever Built

SpaceX to Launch Most Powerful Rocket Ever Built - RF Cafe"SpaceX plans to carry out its first test flight on Monday of Starship, the most powerful rocket ever built, designed to send astronauts to the Moon and eventually beyond. The launch is scheduled to take place at 7:00 am (1200 GMT) from the sprawling Texas base of the private space company owned by billionaire Elon Musk. Fallback times are scheduled later in the week if Monday's attempt is postponed. The US space agency NASA has picked the Starship capsule to ferry its astronauts to the Moon as part of the Artemis III mission, set for late 2025 at the earliest. Starship consists of a reusable capsule that carries crew and cargo and the first-stage Super Heavy booster rocket. The 164-foot (50-meter) tall Starship spacecraft sits atop the 230-foot tall Super Heavy rocket. SpaceX conducted a successful test-firing of the 33 Raptor engines on the first-stage booster of Starship in February..."

Get Your Custom-Designed RF Cafe Gear!

Custom-Designed RF-Themed Cups, T-Shirts, Mouse Pads, Clocks (Cafe Press) - RF CafeThis assortment of custom-designed themes by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins, Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's" design has been ripped off by other people and used on their products, so please be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢ per item - Cafe Press gets the rest of your purchase price. These would make excellent gifts for husbands, wives, kids, significant others, and for handing out at company events or as rewards for excellent service. It's a great way to help support RF Cafe. Thanks...

Please Thank RF & Connector Technology for Their Support

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

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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Amplifier Solutions Corporation (ASC) - RF Cafe
Anritsu Test Equipment - RF Cafe

Windfreak Technologies Frequency Synthesizers - RF Cafe

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