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Homepage Archive - April 2022 (page 1)

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

Thursday the 7th

The Microwave Era Begins

The Microwave Era Begins, October 1950 Radio & Televsion News - RF Cafe"The year 1950 will be recorded historically as the year the microwave relay made its impact felt." That was the closing sentence by Philco Sales Engineer Leo Sands in his 1950 Radio & Television News magazine article entitled, "The Microwave Era Begins." Mr. Sands was not suggesting that it was the start of the widespread use of microwaves in general, but specifically the use of microwaves for long distance, broadband transmission of telecommunications signals. 1950 is about the time microwave relay stations began appearing on hilltops and rooftops of tall buildings all across the land, with the goal of replacing coaxial lines which needed to be strung or buried from end to end. Great cost is associated with a hardline approach for acquisition of land rights, installation, and maintenance. Yes, those kinds of expenses are required for microwave relay stations, too, but in the long run they tend to be much lower, and the service much more reliable and "upgradable." Lots of people opposed the installation of the unsightly, behemoth towers, and many people expressed concern over exposure to microwave energy. If only they knew then how miniscule their worries were compared to today's situation with cell towers within eyeshot of just about ever locations on earth...

Tiny Magnets Hold Secret to Miniaturizable Quantum Computers

Tiny Magnets Could Hold Secret to Miniaturizable Quantum Computers - RF Cafe"From MRI machines to computer hard disk storage, magnetism has played a role in pivotal discoveries that reshape our society. In the new field of quantum computing, magnetic interactions could play a role in relaying quantum information. In new research from the U.S. DOE's Argonne National Laboratory, scientists have achieved efficient quantum coupling between two distant magnetic devices, which can host a certain type of magnetic excitations called magnons. These excitations happen when an electric current generates a magnetic field. Coupling allows magnons to exchange energy and information. This kind of coupling may be useful for creating new quantum information technology devices. 'Remote coupling of magnons is the first step, or almost a prerequisite, for doing quantum work with magnetic systems,' said Argonne senior scientist Valentine Novosad, an author of the study..."

Mac's Radio Service Shop: All Work and No Play

Mac's Radio Service Shop: All Work and No Play, March 1952 Radio & Television News - RF CafeI have to admit to not recalling ever having heard of Dagmar; have you? Crack electronics technician "Red" mentioned her in this episode of "Mac's Radio Service Shop" appearing in the March 1952 edition of Radio & Television News. I thought Prince and Cher were the first man (ostensibly) and woman, respectively, to use a single-name public moniker, but evidently Dagmar beat them to the punch ...but I digress. John T. Frye, author of the popular Carl & Jerry series that appeared later in Popular Electronics magazine, wrote this series before that time. On this cold and wintry day, Red and Mac are discussing troubleshooting methods and how looking for and interpreting certain symptoms can lead to speedy and successful diagnosis and repair. Today's repair shops are mostly changing cracked cellphone LCDs or replacing laptop computer keyboards that have had soda or beer spilled on them, so elaborate technical skills are not needed as much - just a deft touch and steady hands...

Modelithics® April 2022 New Products Blast

Modelithics® April 2022 New Products Blast - RF CafeModelithics just sent out their April New Products Blast, which includes a new Modelithics 3D Brick Model™ for Würth Elektronik's WCAP-CSRF 0402 (NP0) series capacitor, Modelithics models for Coilcraft's 0603CT and 0603HL series inductors, more than 150 Mini-Circuits models, and Modelithics models are available now for the Passive Plus® R35-1209BB and R35-2010BB series. Modelithics is pleased to announce our newest offering of Test Fixtures and Test Accessory products, including legacy parts from J MicroTechnology for a family of thin film Alumina substrate components to adapt the benefits of coplanar waveguide wafer probe test methods to the measurement of devices suited for connection to microstrip circuits. Along with this offering Modelithics is also offering custom coaxial and RF probe test fixtures suited for a wide range of substrate and test interface environments...

How to Use Ohm's Law

How to Use Ohm's Law, February 1956 Popular Electronics - RF CafeFortunately, there is a constant flow of people newly interested in electronics who are seeking information on basic principles. Some will find an article this one on Ohm's law fundamentals and decide maybe being just a user of electronics is good enough. Others will, as did you and I, read this kind of material and be amazed at how ultimately predictable electrical circuit parameters are. If he or she continues and launches into a career in electronics or electrical engineering, it won't be long before he or she will, as do you and I now, look back at how simple things were at the beginning of the journey ;-) This 1956 Popular Electronics magazine article was written half a century ago, but to a word everything contained herein is as valid today as it was then...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. Chances are you have never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed. An intro video takes you through the main features...

Many Thanks to 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.

Wednesday the 6th

News Briefs, November 1959 Radio-Electronics

News Briefs, November 1959 Radio-Electronics - RF CafeRadio-Electronics magazine's November 1959 issue had a few interesting tidbits in the News Briefs section. The first is a note about Major Edwin Armstrong's estate having won a patent infringement case against the Emerson Radio & Phonograph Co. Maybe he wouldn't have committed suicide by jumping out a window if he hadn't had to fight so many IP (intellectual property) battles in his lifetime. Interestingly, the news also mentions that he received more than $5 million in royalties for his FM radio patents. Another item of note is the introduction of secondary radar (aka IFF, identification friend or foe, in military terminology). IFF is not a passive reflected signal system, but uses a transponder in the aircraft to reply to the received signal on an offset frequency. The reply can include parametric information about the aircraft such as altitude, a unique identification (squawk) number, etc. It is a significant enhancement to primary radar, particularly in crowed environments...

Sears, Roebuck Museum in Greensboro, NC

The Sears, Roebuck Museum in Greensboro, NC - 2022 - Airplanes and RocketsCall me a hopeless nostalgist when it comes to favored institutions I grew up with. I miss Pontiac dealerships, Montgomery Ward, and Radio Shack stores. I miss Uncle Ben on the converted rice package, and the indian squaw on the Land O'Lakes margarine package. I miss trips to Blockbuster Video stores on Saturday to pick up a movie on VHS tape, and walking through Toys R Us during the Christmas season. General Foods, Woolworth, Eastern Airlines, Circuit City, Western Auto, Drug Fair, Read's Drug, Britt's Department Stores, Lafayette Radio, A&P Grocery, Northern Reflections, Hechinger Home Improvement, and Babbage's Software. All those and more were part of my growing up in the Annapolis, Maryland area (with Parole Plaza being the prime shopping complex in the era). One of the things I miss the most is the old Sear, Roebuck and Co. stores - particularly the Craftsman tools and lawn and garden sections. My parents bought just about everything from Sears, from us kids' (five of us) school clothing, to household appliances, to lawn mowers, to furniture. Sears' Open Hearth sofas, chairs, end tables, etc. (pretty sure we had this), were nice wood and cloth designs which wore well and were fairly inexpensive. Of course the Sears Wish Book and Montgomery Ward Christmas catalogs...

Altum RF Announces 3 New Amplifiers Covering Q, V, and E-Band

Altum RF Announces 3 New Amplifiers Covering Q, V, and E-Band - RF CafeAltum RF, a supplier of high-performance RF to millimeter-wave semiconductor solutions for next generation markets and applications, announces three new GaAs pHEMT MMIC amplifiers targeting applications covering Q, V, and E-bands. Using WIN Semiconductors' next-generation PP10-20 GaAs pHEMT technology, these compact die amplifiers achieve high gain and low noise, while simplifying design-in for engineers by using single gate and single drain supplies. ARF1208 low noise amplifier - 37-59 GHz, 2.5 dB noise figure and 26.5 dB linear gain (ARF1207 57-71 GHz, ARF1206 71-86 GHz). WIN's PP10-20 technology builds on the proven and mature PP10-10 platform and targets applications up to 170 GHz. As a key differentiator, PP10-20 allows for a substantial increase in gain, with the same operating voltage for power applications. Building on our experience with WIN's proven 0.1 μm technology and with careful attention to modeling, design and simulation workflow, we achieved first-pass success with a family of millimeter-wave products...

After Class: Working with Thermistors

After Class: Working with Thermistors, November 1956 Popular Electronics - RF CafeA good primer on the physics behind and use of thermistors was published in the November 1956 edition of Popular Electronics. Thermistors are fundamentally substances that exhibit a large change in resistance for a given change in temperature, called temperature coefficient of resistance (TCR, or RT). Standard resistors would ideally maintain the exact same resistance regardless of temperature, but in reality most resistor types increase in resistance with an increase in temperature; i.e., a positive TCR. Most thermistors have a negative TCR, which makes them useful for cancelling out resistor temperature sensitivity. Thermistors are also used for temperature sensing and measurement, although thermocouples generally do a much better job for that application...

Semiconductor Measurements Characterize Devices and Materials

Axiom Test Equipment Blog: Semiconductor Measurements Characterize Devices and Materials - RF CafeAxiom Test Equipment, an electronic test equipment rental and sales company has published a new blog post entitled "Semiconductor Measurements Characterize Devices and Materials" that informs people on how semiconductor testing can be conducted. Semiconductors are essential to modern electronics and can be found in almost all electrical products throughout many industries. They come in many forms, with diodes, optocouplers, rectifiers, and transistors among discrete devices. Because semiconductor testing covers such a variety of devices under test (DUTs), it involves many different measurements and, depending on the DUT, often many different test units to perform the measurements. Gaining a better understanding of a semiconductor or the material it is fabricated on requires evaluating it under different operating conditions, such as different voltage (V), current (I), and power levels. In some cases, testing...

All About Electrolytic Condensers

All About Electrolytic Condensers, September 1930 Radio-Craft - RF CafeElectrolytic capacitors have long been the components that provide the highest capacitance density factor, that is, they have the highest capacitance value for a given volume of space occupied. Anyone familiar with electrolytic capacitors is aware of the polarization indicated on the package (a marking or unique physical feature), indicating that there is required direction for hookup; in fact, a backwards connection can lead to an explosive failure. Yes, I know there are now unpolarized electrolytic capacitors available. While physical construction of electrolytic capacitors have evolved over the decades since this article was published in a 1930 issue of Radio-Craft magazine, the fundamental operation has not. It is interesting to note the reference to capacitors as "condensers," a name still commonly used with internal combustion engine ignition systems and with some AC motors that use them at turn-on for providing a starting coil phase shift. Also used here is the term "valve" when referencing the diode...

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 LadyBug Technologies for Their Continued Support!

LadyBug Technologies RF Power Sensors - RF CafeLadyBug Technologies was founded in 2004 by two microwave engineers with a passion for quality microwave test instrumentation. Our employees offer many years experience in the design and manufacture of the worlds best vector network analyzers, spectrum analyzers, power meters and associated components. The management team has additional experience in optical power testing, military radar and a variety of programming environments including LabVIEW, VEE and other languages often used in programmatic systems. Extensive experience in a broad spectrum of demanding measurement applications. You can be assured that our Power Sensors are designed, built, tested and calibrated without compromise.

Tuesday the 5th

Printed Circuits Are Here to Stay

Printed Circuits Are Here to Stay, November 1959 Radio-Electronics - RF CafeI was very surprised to find an example of a rather significant flexible printed circuit substrate in this "Printed Circuits Are Here to Stay," article appearing in a 1959 issue of Radio-Electronics magazine. That era was when much debate, particularly amongst service people, was occurring regarding whether printed circuits would be a welcome replacement for the previous point-to-point wiring method of connecting components and cables. Proponents appreciated the neatness and compactness, while opponents didn't like the lack of robustness and intolerance to heating and pulling off mounted components. What was even more interesting was the mention of a "Persister" element, that was made by Ramo-Wooldridge - the "RW" part of "TRW" (Thompson Ramo Wooldridge, which merged in 1958). A Web search on persister turns up only biological cells which resist antimicrobial treatments...

Exodus AMP2033LC 6-18 GHz SSPA TWT Replacement

Exodus AMP2033LC 6-18 GHz, 100 W SSPA TWT Replacement - RF CafeExodus Advanced Communications, a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide, announces their model AMP2033LC is designed for replacing aging TWT technology. The AMP2033LC is a broadband, rugged EMC Class A/AB linear design for all modulations and industry standards covering 6.0-18.0 GHz. It produces >100 W minimum, with a 50 W P1dB, and a minimum 50 dB of gain. Excellent flatness, optional monitoring parameters for forward/reflected power, VSWR, voltage, current & temperature sensing for superb reliability. Exodus Quiet-Cool technology is featured in our compact 5U chassis weighing a nominal 75 lbs...

Auto Radio - Pro and Con

Auto Radio - Pro and Con, June 1935 Radio-Craft - RF CafeIf you think the controversy over whether drivers being distracted by telecommunications devices is something new, consider this article from a 1935 issue of Radio-Craft magazine. Mobile radio was a relatively new possibility at the time, as was the horseless carriage into which installation was a cause for concern by insurance companies and government regulators. Just as nowadays we worry about and sometimes fining drivers who use a smartphone for texting while driving, the state of Connecticut in 1935 went so far as to propose imposing a fine of $50 ($1035 in 2022 money) for installing a radio set or any "other device which tends to distract the attention" of the operator...

X-Ray Lens Provides Glimpse into Nanoworld

X-Ray Lens Provides Glimpse into Nanoworld - RF Cafe"A microstructure created by a 3D printer: the innovative refractive structure developed by PSI scientists and which combined with a diffractive element, results in an achromatic X-ray lens, is almost a millimeter long (or high, as shown in the photo). Turned on its end, it resembles a miniature rocket. It was created by a 3D printer using a special type of polymer. This image of the structure was captured using a scanning electron microscope. Paul Scherrer Institute scientists have developed a groundbreaking achromatic lens for X-rays. This allows the X-ray beams to be accurately focused on a single point even if they have different wavelengths. The new lens will make it much easier to study nanostructures using X-rays, according to a paper just published by the researchers in the scientific journal Nature Communications..."

Senior RF Engineers Wanted by thinkRF

Senior RF Engineers Wanted by thinkRF - RF CafethinkRF has an opportunity for Senior RF Engineers who can provide technical leadership and innovative support for the next stage in our company's growth. We're looking for people who want to disrupt RF monitoring. We're an ambitious, diverse, closely knit team of RF experts who are driven to redefine how 5G wireless spectrum is monitored and managed. In this role, you would be responsible for the design, simulation, development, and testing of RF circuits and systems for application in wideband radio receivers spanning from DC all the way up to mm wave. You will hold the primary engineering responsibility for electrical design tasks including requirements analysis, specification generation, interface definition, component selection, circuit simulation, symbol creation, schematic capture, and board layout. As the Senior RF Engineer, you will own schedules, cost, and have technical responsibility at the board or subsystem level...

Invisible Light Aids Marksman

Invisible Light Aids Marksman, June 1946 Radio News - RF Cafe"What's the big deal about a night vision scope for your rifle?," you might ask, since I can buy an infrared scope for my rifle on Amazon for under $500. The answer is that no, it is not a big deal now, but in the 1940s while it was being developed and deployed for the military, it was Top Secret. Just as radar is a yawn in any discussion of leading edge technology today, it was vital to keeping the free world free. It wasn't until after World War II had ended that infrared scopes found their way into unclassified articles, but even then the cost was way more than any non-governmental entity could afford. The Night Owl Optics NightShot Digital Night Vision Riflescope from Amazon is not a top-end product, but chances are that being all solid state it performs at least as well as the beast shown in this article and is much more rugged than the vacuum tube based 1940s design. Note that the Army guy is wearing a backpack just to hold the battery...

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 KR Electronics for Long-Time Support!

KR ElectronicsKR Electronics designs and manufactures high quality filters for both the commercial and military markets. KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop and individually synthesized filters for special applications - both commercial and military. State of the art computer synthesis, analysis and test methods are used to meet the most challenging specifications. All common connector types and package form factors are available. Please visit their website today to see how they might be of assistance. Products are designed and manufactured in the USA.

Monday the 4th

Garod Model 6AU-1 Radio Data Sheet

Garod Model 6AU-1 Radio Data Sheet 341, November 1946 Radio-Craft - RF CafeThis data sheet with schematic and aligning procedures for the Garod model 6AU−1 tabletop radio appeared in the November 1946 issue of Radio−Craft magazine. It was AM only (shortwave and FM were not in use yet), and operated off of batteries (DC) or the AC line. It was one of the earlier radio to use a Bakelite-like phenol formaldehyde resin material for the cabinet rather than the more traditional wood. Molded plastic was not yet a thing in high volume commercial production. The brown (or bright red) and gold motif was considered avant-garde (aka Art Deco) compared to the more conservative solid and wood laminate finishes. There was also a version with orange case and red grille. The overall size was 11" wide x 6.5" high x 6" deep. There are many finely restored exampled around the Internet...

Small Details Matter When It IS Rocket Science

NASA's Artemis Heavy Lift Booster - RF CafeI have been following the progress of NASA's new Artemis heavy lift rocket, designed to be bigger and better than the Apollo era Saturn V booster. Not needing to hitch rides on Russian and Chinese rockets anymore would be nice. The agency's "Artemis I Launch Countdown 101" page defines and details some of the terminology and schedule items, including the pre-launch timeline. It includes not only the familiar "T−minus..." countdown benchmarks but also the "L−minus" (L being launch) milestones. The very first item in the "L−minus" as of this writing says, "L−45 hours and counting: The launch team arrives on their stations and the countdown begins (L−45, 40 minutes hours)." That should be "(L−45 hours, 40 minutes)," a la the other items in the list. You might recall the spectacular and sickening crash of NASA's Mars Climate Orbiter into the red planet in 1999. A simple lack of proper conversion from metric to SI units was identified as the culprit. I look forward to the return of a U.S. capability of launching manned missions again (dead since the Space Shuttle program shut-down in 2011), and certainly hope such a lack of attention to details will not doom it from the start (or maybe the L-45 hours, 40 minutes point). Oh, and there's also a misspelling on the page (coundown vs. countdown). The devil is in the details, as the saying goes.

Carl & Jerry: Extra Sensory Perception

Carl & Jerry: Extra Sensory Perception, December 1956 Popular Electronics - RF CafeCarl and Jerry were early adopters of the near field communications (NFC) craze that is going full-swing today. As they often do, the harmlessly mischievous teenage duo used their combined grasp of modern electronics to pull off gags on unsuspecting friends ... and sometime adversaries. In this episode, a near-field transmitter and receiver pair is designed to help Carl bedazzle a scientist who was attempting to disprove the ability to use "Extrasensory Perception" (ESP) - the title of this 1956 Popular Electronics magazine technodrama - to determining what another person was thinking about. In this case it was detecting which playing card was being displayed on an overhead projector. Of course Carl didn't really have "the gift," but relied on his co-conspirator, Jerry...

The Periodic Table of Substitute Performance

The Periodic Table of Substitute Performance - RF CafeIn a Scientific American article titled "Elemental Urgency," Jennifer Hackett reported on a paper published in 2013 by Yale University's Thomas Graedel et al regarding the availability (or unavailability) of the raw elements - and suitable substitutes - used extensively in modern manufacturing. Unlike half a century ago when most products were made from relatively common and easily obtainable elements like lead, iron, tin, nickel, aluminum, carbon, zinc, silicon, and even silver and gold, many more elements are now regularly included in mass manufacturing processes. Rhenium (Re), used in high strength, temperature alloys to applications like jet engine turbine blades and as a catalyst in chemical processes, is one of the most critically rated elements for uniqueness. Ditto for titanium. Yttrium (Y), used in the familiar YIG oscillator and YAG laser, is another critical element. Keep in mind that this chart rates elements not solely according to scarcity, but how critical they are in processes where no other element can be substituted in the event of a shortage. Lead (Pb) is a clear example of an element that is abundantly available, but the materials in which it is used cannot be easily replaced with another element...

Get Your Custom-Designed RF Cafe Gear!

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

Many Thanks to ISOTEC for Continued Support!

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

Sunday the 3rd

Filter Themed Crossword Puzzle for April 3rd

Filter Themed Crossword Puzzle for April 3rd, 2022 - RF CafeHere is your custom made Filter-themed crossword puzzle for April 3rd, 2022. Clues for words relevant to the theme are marked with an asterisk (*). All RF Cafe crossword puzzles are custom made by me, Kirt Blattenberger, and have only words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects. As always, this crossword contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

RF & Electronics Symbols for Office™

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

Thanks to TotalTemp Technologies for Continued Support!

TotalTemp Technologies - RF CafeTotalTemp Technologies has more than 40 years of combined experience providing thermal platforms. Thermal Platforms are available to provide temperatures between −100°C and +200°C for cryogenic cooling, recirculating circulating coolers, temperature chambers and temperature controllers, thermal range safety controllers, space simulation chambers, hybrid benchtop chambers, custom systems and platforms. Manual and automated configurations for laboratory and production environments. Please contact TotalTemp Technologies today to learn how they can help your project.

Friday the 1st

The American Radiator Delay League

The American Radiator Delay League, April 1933 QST - RF CafeHumor in 1933 was evidently very different than it is today. This is part of what was in the April edition of the ARRL's QST magazine from that year. Unlike the unannounced "April Fools" features that may or may not appear in a given year's April issue nowadays (the April 2022 issue of QST has a gag article on page 40 - the page 38 article is actually real), much ado was made over the gags back in the day. You might have noticed the humor in some of the older electronics-themed comics also sometimes invokes the "what am I missing?" response. Shown below on the left is the gag table of contents page and on the right is the "real" table of contents. I get the thumbing the nose by the little dude in the margin, and I get the play on American Radio Relay League, but what the hey does "Liberian Dog-Apple Growing" mean? Any ideas? Maybe you'll be able to appreciate the intended humor here...

Acoustic Fiber Turn Fabrics into Mics and Speakers

Acoustic Fiber Turn Fabrics into Mics and Speakers - RF Cafe"Batteries, circuitry, displays, and other devices are increasingly made in fabric form, leading to more and more powerful electronic textiles. Now scientists have developed an acoustic sensor consisting of a single fiber that can turn fabrics into microphones and speakers, for potential applications in two-way communications, detecting the directions of gunshots, and monitoring fetal heartbeats during pregnancy, a new study finds. The new sensor consists of a fiber that is piezoelectric - that is, capable of converting vibrations to electricity, and vice versa. This acoustic fiber is embedded within a fabric consisting of a relatively soft cotton yarn, as well as a yarn roughly as stiff as Kevlar. Previous acoustic fibers suffered from low sensitivity in air. Moreover, fabrics normally muffle sound—for instance, carpets often help do so in homes. In contrast, this new research actually makes use of the fabric the acoustic fiber is woven into to help the sensor detect airborne sounds, a strategy inspired by the complex structure of the human ear..."

Radium-Radio Receiver

Radium-Radio Receiver, April 1944 Radio-Craft - RF Cafe"Necessity is the mother of invention," is a common saying that proves itself to be particularly true in times of war. World War II launched scientists and engineers belonging to both the Axis and the Allied powers into inventive frenzies in their efforts to hasten an end to hostilities; of course each side also wanted to be the victor. We all know how the story ended. Although some countries were not immediately able to capitalize on their countrymen's technical advances, within about a decade normalized relations had been established between former foes, and the exchange of products, services and scientific information proceeded. Some discoveries were deemed too valuable to national security and were therefore not divulged even, in some instances, to friendly nations. Many scientists consider themselves to be "citizens of the world" and vehemently object to not sharing all available knowledge out of a belief...

Anatech Intros 3 Filter Models for Early April 2022

Anatech Electronics Intros 3 Filter Models for Early April 2022 - RF CafeAnatech Electronics offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. Three new filter models have been introduced - a surface mount 536 to 632 MHz ceramic bandpass filter, a 707 to 710 MHz / 734 to 740 MHz ceramic duplexer filter, and a 5.5 to 23 GHz suspended stripline highpass filter with SMA connectors. Custom RF power directional coupler designs can be designed and produced when a standard cannot be found, or the requirements are such that a custom approach is necessary...

Contra-Polar Energy

Contra-Polar Energy, April 1955 Popular Electronics - RF CafeContra-polar (negative) energy is a concept that has been investigated by many researchers beginning in the mid 19th century, when the nature of energy was beginning to be understood from a truly scientific perspective. Entire theories of universe and matter-antimatter creation have been published, reviewed and refined. This article from the April 1955 edition (note the month) of Popular Electronics reports on then-current applications of contra-polar energy. At the time, most such work was performed in secret government laboratories and at test ranges that were closed to the public and results banned from publication, but since that time freedom-of-information-act requests have opened much contra-energy research information for public access...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. Chances are you have never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed. An intro video takes you through the main features...

Many Thanks to LadyBug Technologies for Their Continued Support!

LadyBug Technologies RF Power Sensors - RF CafeLadyBug Technologies was founded in 2004 by two microwave engineers with a passion for quality microwave test instrumentation. Our employees offer many years experience in the design and manufacture of the worlds best vector network analyzers, spectrum analyzers, power meters and associated components. The management team has additional experience in optical power testing, military radar and a variety of programming environments including LabVIEW, VEE and other languages often used in programmatic systems. Extensive experience in a broad spectrum of demanding measurement applications. You can be assured that our Power Sensors are designed, built, tested and calibrated without compromise.

   

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TotalTemp Technologies (Thermal Platforms) - RF Cafe
RF Cascade Workbook 2018 by RF Cafe
RF Electronics Shapes, Stencils for Office, Visio by RF Cafe
Lotus Communication Systems Modular RF Component Building Blocks - 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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