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Berkeley Nucleonics IMS 2022 Booth 9072 - RF Cafe
 

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...

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

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Today in Science History

Tech Industry Headlines

Tech Industry Headlines - RF Cafe - Archive -

5/27/2022

• Canada to Ban Huawei and ZTE from 5G Networks

• CERN's Large Hadron Collider Gears up for Run 3

• Boosting Prospects of PhD Students Before and After Graduation

• Remembering 1982 IEEE President Robert Larson

• Global RAN Market Grows Despite Supply Chain Issues

• FCC Discovers Computers

• Webb Telescope Nearly Ready for "First Light"

• Undersea Fiber Cables Detect Seismic Events

• Time to Re-Assess Spectrum Strategy

• Democratic Socialist Republic of Sri Lanka Phone App Enforces Gas Rationing

Digital Engineering Theme Crossword for May 29th

Digital Engineering Theme Crossword Puzzle for May 29th, 2022 - RF CafeThis custom Digital Engineering themed crossword puzzle for May 29th, 2022, is brought to you by RF Cafe. Clues for words relevant to the theme are marked with asterisks (*). I do believe this is the first digital electronics crossword I have ever made. 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!

Many Thanks for Alliance Test Equipment's Support!

Allied Test Equipment Products - RF CafeAlliance Test Equipment sells used / refurbished test equipment and offers short- and long-term rentals. They also offer repair, maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP, Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization with ability to source hard to find equipment through our network of suppliers. Alliance Test will purchase your excess test equipment in large or small lots. Blog posts offer advice on application and use of a wide range of test equipment. Please visit Allied Test Equipment today to see how they can help your project.

Radio-Electronics in the Atomic Energy Program

Radio-Electronics in the Atomic Energy Program, September 1949 Radio & Television News - RF CafeAtomic energy research came to the forefront of public awareness in 1945 following the detonation of the world's first nuclear bombs. X-rays had been studied for decades and uses had been developed for medical and industrial inspection purposes, but the harmful effects of low level exposure over long periods of time were still largely undetermined. Some people, like the author of this report from a 1949 edition of Radio & Television News magazine, believed "man's life is shortened by exposure to any amount of radioactivity." That was a rather extreme and alarmist statement to make in an article whose purpose was ostensibly to encourage engineers, scientists, and technicians to seek careers in the radio-electronics-nucleonics field...

Practical Power Beaming

Practical Power Beaming - RF CafPower beaming is one of those things I view as useful for hard to access installations, but very inefficient for anything other than low power applications. This article in IEEE's Spectrum magazine provides some insight into the state of the art. "Wires have a lot going for them when it comes to moving electric power around, but they have their drawbacks too. Who, after all, hasn't tired of having to plug in and unplug their phone and other rechargeable gizmos? It's a nuisance. Wires also challenge electric utilities: These companies must take pains to boost the voltage they apply to their transmission cables to very high values to avoid dissipating most of the power along the way. And when it comes to powering public transportation, including electric trains and trams, wires need to be used in tandem with rolling or sliding contacts, which are troublesome to maintain, can spark, and in some settings will generate problematic contaminants. Many people are hungry for solutions to these issues - witness the widespread adoption over the past decade of wireless charging..."

Mac's Radio Service Shop: Barney Is a Big Boy Now

Mac's Radio Service Shop: Barney is a Big Boy Now, January 1949 Radio & Television News - RF CafeDon't let the title fool you. This is not a "bees-birds-and-flowers routine" being provided to Barney by his boss, Mac. It turns out to be a brief introduction into the fine art of troubleshooting intermittent problems in radio and television circuits. As is usually the case, while the specifics of the scenarios Mac describes might not apply to your challenge at hand, the general philosophy always does. It is basically the old process of elimination where after rapping components mechanically and/or heating or cooling them in hopes of observing a tell-tale change in performance, the next step is to divide the suspected circuit portion in half (electrically, but sometimes also physically) and look in one direction. If the problem isn't there, then divide the circuit in the other direction in half and go there. Repeat until the problem is found. One of my personal favorite first steps is to verify all mechanical connector interfaces (if any) are contacting properly. Clean with alcohol if possible, and burnish with sandpaper if appropriate, then plug and unplug the connections a few times, just to make sure proper seating...

Anatech Electronics May 2022 Newsletter

Anatech Electronics May 2022 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his May 2022 newsletter that features his short op−ed entitled "This Will Be the Year That Matter, Matters," where he describes how "Matter," which was formerly called Project CHIP (Connected Home over IP) and then Connectivity Standards Alliance (CSA), was announced in December 2019 with the goal of reducing fragmentation and eliminate interoperability issues with home automation. As with Wi-Fi and Bluetooth, Matter aims to assure compatibility between systems and devices of all manufacturers. Also in the news is the ongoing saga of C-Band cell service and radar altimeter interference, "Smart Agriculture" revenue projections, and rectenna RF energy harvesting...

Television Forges Ahead

Television Forges Ahead, March 1930 Radio News - RF CafeSome of the earliest television display schemes were mechanically scanned light projection systems rather than electronically raster scanned cathode ray tubes. This 1930 vintage article from Radio News magazine reports on a scheme developed by Arthur Watson whereby a specially formed rotating Monel disk served as the rotating reflecting surface to produce the light scanning action. This invention was hailed as a breakthrough that would finally make commercial TV available to the masses. Mechanical televisions worked by transmitting scanned images of the original subject in the form of amplitude modulated electrical signals whose voltage was determined by the level of reflected light. A synchronizing signal was included in the transmitted data stream. The scan disk on the receiving end rotated at the same rate as the transmitter scanning disk, and an electric lamp's brightness was varied according to the signal's picture voltage level...

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...

Please Thank RF Superstore for Their Continued Support

RF Superstore coaxial cable, connectors, adapters - RF CafeRF Superstore launched in 2017, marking the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and microwave Industry. Pasternack fundamentally changed the way RF components were sold. Partner Jason Wright manages day-to-day operations, while working closely with Mr. Pasternack to develop RF Superstore into a world class RF and microwave component supplier. RF coaxial connectors & adapters, coaxial cable & cable assemblies, surge protectors, attenuators. Items added daily. Free shipping on orders over $25. We're leading the way again!

Ultrasonic Communications

Ultrasonic Communications, October 1945 Radio News - RF CafeThat ultrasonic communications has not proved to be a reasonable means of transmitting information from one location to another - even over fairly short distances - is borne out by the obvious lack of such systems today. With all the technology available in the form of electronics, mechanics, and software, if it were possible to efficiently and effectively implement systems of ultrasonic communications, such devices would be as common as the current plethora of wireless systems. Some early research efforts at ultrasonic communications were published in a 1945 edition of Radio News magazine. Regardless of the era, the electromagnetic frequency bands are always deemed to be too crowded so researchers constantly look for other transmission media. There is one revolutionary new potential form of remote communications on the horizon: quantum entanglement. Still largely an enigma, entanglement communications exploits an observed property of some subatomic particles to be inextricably linked to each other with no discernable medium or known mechanism...

Thanks Again for Windfreak Technologies' Continued Support!

Windfreak TechnologiesWindfreak Technologies designs, manufactures, tests and sells high value USB powered and controlled radio frequency products such as RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters. Since the conception of WFT, we have introduced products that have been purchased by a wide range of customers, from hobbyists to education facilities to government agencies. Worldwide customers include Europe, Australia, and Asia. Please contact Windfreak today to learn how they might help you with your current project.

Arduino-Powered Color Mechanical Television

Arduino-Powered Color Mechanical Television - RF CafeThis is very cool if you have an interest in the early developments in television. I have posted many articles from vintage electronics magazines documents in the evolution of color TV.  This piece entitled "Print an Arduino-Powered Color Mechanical Television" appeared on the IEEE Spectrum website. It begins: "Before flat screens, before even cathode-ray tubes, people watched television programs at home thanks to the Nipkow disk. Ninety years ago in places like England and Germany, broadcasters transmitted to commercially produced black-and-white electromechanical television sets, such as the Baird Televisor, that used these disks to produce moving images. This early programming established many of the formats we take for granted today, such as variety shows and outside broadcasts. The size and weight of a Nipkow disk makes a display with more than a few dozen scan lines impracticable (in stark contrast to modern screens with thousands of lines). But when a mechanical TV is fed a moving image, the result is surprisingly watchable..."

Chinese Vacuum Tube Manufacturing

Chinese Vacuum Tube Manufacturing, October 1945 Radio News - RF Cafe1945 or 2022? Seventy-seven years have passed since this photo of a vacuum tube manufacturing facility in China was taken. Given that most new vacuum tubes are made in China, and that the labor work conditions have not changed much in the intervening time period (except in high-profile plants like Foxconn where Apple products are made), this might very likely represent a modern day operation. BTW, most of the vacuum tubes not being made in China are made in Russia... to assure their antiquated infrastructure has an ample supple of replacement parts. I say that only partly in jest. The largest market for new vacuum tubes is music amplifier equipment and a few commercially made vintage radio replicas (like the Tesslor Model R601S). BTW, Western Electric (the telephone manufacturer for Bell, back in the day) is now manufacturing vacuum tubes again...

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 Reactel for Their Long-Time Support!

Reactel Filters - RF Cafe

Reactel has become one of the industry leaders in the design and manufacture of RF and microwave filters, diplexers, and sub-assemblies. They offer the generally known tubular, LC, cavity, and waveguide designs, as well as state of the art high performance suspended substrate models. Through a continuous process of research and development, they have established a full line of filters of filters of all types - lowpass, highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact Reactel today to see how they might help your project.

Test Your Knowledge of Semiconductors

Test Your Knowledge of Semiconductors, August 1972 Popular Electronics - RF CafeThe August 1972 issue of Popular Electronics included a short quiz by William Shippee titled "Test Your Knowledge of Semiconductors." I guessed wrong on question #2, but guessed right by process of elimination on question #8 (although afterward I discovered that in 2012 I had posted an article about the #8 device in Electronics World magazine). Go ahead and take your best shot. You might be surprised at how much you've forgotten if you don't work with transistors on a regular basis. I'll bet Q2 has most people guessing, too...

Using Sub-Milliohm SMD Chip Resistors

Challenges of Using Sub-Milliohm SMD Chip Resistors - RF Cafe"Treating sub-milliohm chips as a separate class of component is a smart strategy that helps solve associated design challenges. Part 2 of this series features strategies for verification of the ohmic value of unmounted components and critical assembly. The growing use of sub-milliohm chip resistors for current sensing creates a spectrum of challenges for the designer and the process engineer. The component format should first be selected to support the chosen thermal-management approach, with metal-element flat chip resistors having two terminals being the most cost-effective solution. It's then essential to design the PCB tracks and pads to meet the needs of Kelvin connection, heat dissipation, and avoidance of induced noise..."

The "Kit" Has Finally Been Put Back in Heathkit!

The "Kit" Has Finally Been Put Back in Heathkit™ ! - RF CafeI signed up as a "Heath Insider" about a year ago when news first broke about Heathkit's intention to finally, after a couple decade hiatus, begin producing built-it-yourself electronics kits again. The Explorer Jr.™ is a basic capacitor-tuned AM radio kit that comes complete with everything needed to build it. Why not a digitally tuned synthesizer with an LCD display? Company president Andy Cromarty promises many more kits to follow, with all being in the classic Heathkit tradition of high quality parts and well-written, illustrated, step-by-step instructions. It will be a continuation of their "You Can Build It. We won't let you fail." motto. Since originally posting this page in 2015, Heathkit has been making slow but steady progress with expanding their line of build-it-yourself projects. They also now have a cool T-shirt design showing an exploded view of their "Most Reliable Clock™" model GC-1006, with the proclamation "Heathkit's Back. It's About Time."

ARRL Lightning Calculators Advertisement

ARRL Lightning Calculators Advertisement, May 1939 QST - RF CafeThe ARRL (American Radio Relay League) might be considered as one of the first app developers. At 50¢ and $1 per app, the price was in-line with one of today's typical not-for-free Apple or Android app. A user willing to shell out $4 for all six had at his fingertips calculators and reference tables for capacitive and inductive reactance, resonant frequency, gain and power, conductor amperage, transformer turns ratio, resistor, capacitor, and inductor series and parallel combination, and other values. These six apps, dubbed "Lightning Calculators," were comprised of bit of cardboard, plastic, and a metal eyelet, not data bits. Here is a for-real Type B "Lightning Calculator," graciously provided by Joseph Birsa, N3TTE...

Beware the Service Gyp!

Beware the Service Gyp!, September 1934 Radio-Craft - RF CafeRepair service businesses have always gotten a bad rap for deliberately inflating part and labor costs - often deservingly so - but it's a shame the honest brokers are dragged down by the scum (or "gyps" as this article calls them). Come to think of it, the word "gyp" is likely short for "gypsy," which is sure to offend someone these days. Along with admonishing customers to beware of shyster servicemen, there is an example of an orchestrated "sting" operation whereby a radio set was intentionally "broken" in a certain way with witnesses as to the fault, and then a couple dozen repair services were called upon to troubleshoot and fix it, then present a bill for their work. The result is interesting, and even resulted in one guy being prosecuted. The story reminds me of a similar much-publicized sting that was done back in the 1990s against car repair services that were creating leaks in brake lines and then charging customers to fix them...

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.

The Radio Month, March 1954 Radio-Electronics

The Radio Month, March 1954 Radio-Electronics - RF CafeThis 1954 issue of Radio-Electronics magazine reported on the death of electronics communications pioneer Major Edwin H. Armstrong. Most famously known for his wideband FM (frequency modulation) scheme, Maj. Armstrong also developed the superheterodyne circuit, the superregenerative circuit, and was an independent inventor of regeneration. As with many prodigious, prolific inventors throughout the ages, he spent much time and fortune battling legal claims against himself and against others. Interestingly, the news item does not mention that Major Armstrong, who was famous for his daring antics at the tops of extremely high antennas, died after jumping out of his New York City apartment window. It was ruled a suicide based on a note he left for his wife. Also included is a bit about a judge allowing radar data from police as evidence in a speeding charge, and a statistic showing 47,000 people injured themselves in the past year during TV antenna installations...

Before GPS, There Was the Fresnel Lens

Before Ships Used GPS, There Was the Fresnel Lens - RF CafeAugustin-Jean Fresnel, the same guy who developed the "Fresnel zone" equation for determining the effective RF propagation region between a transmitter and a receiver, also invented this prismatic lens for concentrating the source of illumination of a lighthouse in the direction most useful to seafaring vessels (aka ships and boats). This IEEE Spectrum article entitled "Before Ships Used GPS, There was the Fresnel Lens" dives into the history of the world-changing device. It begins: "Ships today use satellite-based radio navigation, GPS, and other tools to prevent accidents. But back at the beginning of the 19th century, lighthouses guided ships away from rocky shores using an oil lamp placed between a concave mirror and a glass lens to produce a beam of light. The mirrors were not very effective, though, and the lenses were murky. The light was difficult to see from a distance on a clear night, let alone in heavy fog or a storm..." Here is a nice video explaining the Fresnel lens and its nautical import.

Zenith Models 5D011-5D027 Schematic & Parts List

Zenith Models 5D011-5D027 Schematic & Parts List, February 1947 Radio News - RF CafeHere is Zenith Models 5D011-5D027 schematic and parts list as featured in a 1947 edition of Radio News magazine. Unlike with most of the Radio Service Data Sheets, this came from group of three which also included the Bendix Models 636A, C, D and the Coronet Model C-2, al three of which are tabletop models. As mentioned many times in the past, I post these online for the benefit of hobbyists looking for information to assist in repairing or restoring vintage communication equipment...

Planar Monolithic Industries dba Name Change to Quantic PMI

Planar Monolithic Industries dba Name Change to Quantic PMI - 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, announces a dba (doing business as) name change to Quantic PMI. They also have introduced a new 6−Channel Switch Filter Bank that operates over the frequency range of 55 to 18.5 GHz, with a typical VSWR of 1.7:1, a maximum switching speed of 200 ns, and a typical insertion loss of 4.0 dB. Contact PMI today for more information...

Electronics-Themed Comics

Electronics-Themed Comics March 1952 Radio & TV News - RF CafeThese two electronics-themed comics appeared in a 1952 edition of Radio & Television News magazine. In the early days of television, it was common in comedy skits and in cartoons to have someone on a television show interact, to the viewer's great shock, directly with the viewer or to reach out of the set and do something, as in the first comic here. The Three Stooges show did that in a couple shows. One in particular I remember was when they were doing plumbing in a house and had water coming out of light sockets and telephones. The homeowners were watching the TV with a film of Niagara Falls when suddenly water came gushing out of the picture tube (begins at 13:20 in video)...

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 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.

Radio Stamps Make Rare Collection

Radio Stamps Make Rare Collection, July 1956 Popular Electronics - RF CafeBoth my father and grandfather were stamp collectors - philatelists is the technical word - who dabbled in a recreational way with commemoratives from foreign countries. Nearly all were canceled (used) stamps that today, as back in their day, have no real value other than to someone interested in history. Of course none are the rare types. I now possess many of those stamps in an album that was painstakingly hand-illustrated and assembled to arrange each stamp according to its country and issue date. At one time I, too, dabbled in the hobby, having collected many plate blocks and special issue U.S. stamps in the 1970s and 1980s, along with purchasing a few designs of special purpose such as those with aerospace and communications themes. Sad to say, most of those stamps, even those in mint condition, are valued at the denomination printed on the face - meaning inflation has reduced their worth to even less than when originally purchased. If indeed "what's past is prologue...

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