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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...

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

My Hobby Website:

AirplanesAndRockets.com

Anatech Electronics - RF Cafe

Homepage Archive - March 2022 (page 1)

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

Tuesday the 8th

TV DX in 1953

TV DX in 1953, January 1954 Radio-Electronics - RF CafeSporadic E propagation has been a significant source for long-distance (DX) radio signal communications for voice, and Morse code (CW) for as long as radio has been around, with digital data having joined the activity sometime around the 1970s. Many contest are organized around the phenomenon where the regions of the ionosphere's E-layer are to some extent randomly (as "sporadic" suggests) ionized by solar electron ejections in a manner that renders it highly conductive to certain wavelengths - primarily VHF (30-300 MHz). VHF is typically a line-of-sight transmission path. Via one or more jumps, signals can travel very long distances, even half-way around the world. Just as radio listeners considered it a challenge to pick up broadcasts from far away, so, too, did some television watchers. I know a couple guys who in the 1960s and 1970s engaged in the TV DX sport. One says he could sometimes pick up, say, Miami, Florida from his home in Madison, Wisconsin. Another living as a kid in Bangor, Maine, claims to have picked up TV stations in Puerto Rico. This 1954 Radio−Electronics contains many instances of reports from avid TV DXers who...

Intel's "Evolution of Transistor Innovation"

Intel's "Evolution of Transistor Innovation" - RF CafeOne of the news websites I frequent had a note about this "Evolution of Transistor Innovation" video produced by Intel. In a span of five minutes you are taken on a journey from the early planar MOSFET (metal oxide semiconductor field effect transistor) days to today's world of 3-dimensional, non-planar FINFET (fin field effect transistor). Physical layout, materials, and lithography advances allowed gate lengths to shrink from 12 μm in the early 1970s to a mere 10 nm by 2020. Switching speeds have gone up, die sizes have gone down, power consumption per gate has decreased, and reliability has increased. At every juncture we have been served stories of a certain end to Moore's law (a doubling of gate count every 18-24 months), and thanks to dedicated engineers and scientists the prognosticators have been proven wrong...

Teledyne e2v HiRel 100 V, 20 MHz FET and GaN Transistor Driver Flip Chip

Teledyne e2v HiRel Announces New 100 V High-Speed 20 MHz FET and GaN Transistor Driver Flip Chip Die - RF CafeTeledyne e2v HiRel announces the new TD99102 UltraCMOS® High-speed FET and GaN transistor driver offering very high switching speed of 20 MHz. The new flip-chip part is ideal for driving Teledyne HiRel's 100 V high reliability GaN HEMT devices in DC-DC, AC-DC converters, orbital Point-of-Load (POL) modules and space motor drives. The TD99102 is an integrated high-speed driver designed to control the gates of external power devices such as enhancement mode gallium nitride (GaN) High Electron Mobility Transistor (HEMT) and power MOSFETs. The outputs of the TD99102 are capable of providing switching transition speeds in the sub-nanosecond range for switching applications up to 20 MHz. The TD99102 is optimized for matched dead time and offers best-in-class propagation delay to improve system bandwidth. High switching speeds result in smaller peripheral components and enable innovative designs for high reliability orbital motor driver and POL applications...

Garod Model 5A1 "Ensign" Tabletop Radio

Garod Model 5A1 "Ensign" Tabletop Radio Schematic & Parts List, September 1947 Radio News - RF CafeHere are the schematics and parts list for the Garod model 5A1 "Ensign" tabletop radio. They appeared in the September 1947 issue of Radio News magazine. Unlike with a lot of these service data sheets, there was no textual description of the circuit functions or an alignment procedure. A nicely restored example of the Garod 5A1 "Ensign" Tabletop radio can be seen on the RadioMuseum.org website. 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. That makes today's situation similar to what existed back in the era where such information was difficult to obtain without having an inside line to the manufacturer. I keep a running list of all data sheets to facilitate a search...

NASA's Shortcut to Fusion Power

NASA's Shortcut to Fusion Power - RF CafeHere is a great article reporting on a recent breakthrough in nuclear fusion for electrical power generation - Lattice Confinement Fusion (LCF). My first thought was that this is the latest cold fusion gimmick, but the method is distinctly different. The author does a nice job of stepping through the evolution of nuclear fusion research as he arrives at the new method which manages to store fusible elements at a density only 3 orders of magnitude lower than that required for spontaneous fusion - and at room temperature! Pumping in a relatively low level of excitation power is enough to trigger the reaction, which continues only for as long as the stimulus persists; i.e., totally controlled. I thought for sure by now we would have fusion reactors online, having read of this technology since the early tokamak days in the 1970s with promises of unlimited sun-like power generation. We'll be waiting a while longer, though, since this is still nowhere near a break-even point of power input vs. power output. In the mean time, I'll keep rooting for the researchers.

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 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.

Monday the 7th

Serviceman's Experiences

Serviceman's Experiences, February 1942 Radio News - RF CafeIronically (for me, anyway), this "Serviceman's Experiences" feature from a 1942 issue of Radio News magazine was the next on my to−do list of stories right after "An Inside Story About Metal Tubes" which appeared in a 1935 edition of Radio−Craft magazine. Two entire issues were dedicated to the subject. Vacuum tubes with metal casings were relatively new in 1935 and would, according to prognosticators of the day, quickly supplant the normal glass enclosure, but history shows they never did; glass tubes were still in the majority up until the time they were finally nearly totally phased out by semiconductor devices in the early 1970s. In this article, the dialog opens with servicemen complaining about needing to remove metal tubes from their sockets in order to see the part number markings, but that is not the moral presented in the saga. Rather, the takeaway here for service businesses is to be sure to leave a customer satisfied that you care about your reputation and your customer's needs more than making a profit. Many episodes of Mac's Service Shop emphasize the same thing. I'm not sure how far you should go...

An Inside Story About Metal Tubes

An Inside Story About Metal Tubes, October 1935 Radio-Craft - RF CafeMetal-encased vacuum tubes were such a big deal when they arrived on the scene in the mid 1930s that two successive issues of Radio-Craft devoted the majority of print space to them. Metal tubes, as admitted by editor and author Hugo Gernsback, did not perform as well electrically as glass tubes yet, but that was attributed to the infancy of the technology. Overwhelming positives, including ruggedness, lower cost of production, longevity (lifetime) and other aspects would ensure that metal tubes "are here to stay." They never did even come close to replacing glass tubes. One of the most interesting statements in the article has nothing to do with metal tubes, but Mr. Gernsback's understanding of special relativity; to wit, "...unless you have Einsteinian faculties that enable you to look around corners." In 1935, a mere three decades after Einstein published is theory, very few people had even heard of the phenomenon...

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!

An 18 Metal-Tube All-Wave Superhet

An 18 Metal-Tube All-Wave Superhet, October 1935 Radio-Craft - RF CafeAs I have written in a couple articles, there was a huge push in the mid 1930s to adopt the revolutionary new metal-encased vacuum tubes over established glass-encased tubes. The entire October 1935 issue of Radio−Craft magazine was dedicated to extolling the virtues of using metal tubes, entirely eliminating glass tubes in all sockets, "with a resulting improvement in selectivity, sensitivity and a marvelous increase in fidelity of tone." Today, interest in vacuum tube amplifiers is building among audio enthusiasts both from a nostalgic perspective and from a long-perpetuated belief that sound from vacuum tube circuits have a distinctively richer audio quality than that of solid state devices due to the microphonics of the physical elements which expand and contract with the signal. I post this stuff for the benefit of those who otherwise might not be able to find the information otherwise...

CMT's New S5180B Compact VNA w/Pulse Modulation Option

Copper Mountain Technologies S5180B Compact VNA with Pulse Modulation Software Option - RF CafeCopper Mountain Technologies' S5180B 2-Port 18 GHz Compact VNA will serve as an enhanced version of its predecessor, the S5180 Compact VNA. S5180B is the first CMT VNA with built-in Pulse Modulation Generation/Measurement capabilities which will expand measurement proficiency for the development, manufacturing, and testing of high-power amplifiers. The Pulse Modulation feature is a paid software option sold separately from the VNA and is only compatible with the S5180B VNA due to hardware requirements. The Pulse Modulation option can be added at any time during or after the initial VNA purchase. Pulse modulated measurements are useful for high power amplifier development, manufacturing, and testing, especially on-wafer components where a heat sync isn't practical. 5180B has built-in hardware to support various types of pulse measurements when used with the Pulse Modulation software option. Pulses can be generated...

Listening Post in the Philippines

Listening Post in the Philippines, April 1946 QST - RF CafeHere is a fascinating story from a 1946 issue of the ARRL's QST magazine of the ordeal one Catholic priest experienced while serving in the Philippines during the Japanese occupation in World War II. Father Visintainer exploited his personal interest in radio communications to help keep local residents apprised of the war's progress and talk to the outside world. Japanese troops confiscated all the existing shortwave radios and converted them to their own frequencies. Some were re-converted by daring servicemen and then hidden. Batteries were recharged using covert water wheel powered generators located in the woods. Drama hit a peak one day when an attempt to formulate a make-shift battery electrolyte resulted in an explosion that brought Japanese running to the church lab. For a guy who claims, "But I am not a chemist," he has an amazing knowledge of chemicals. Read on to learn how Father Visintainer escaped certain death...

RF & Electronics Symbols for Visio

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

Many Thanks to 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.

Sunday the 6th

Radio Technology Theme Crossword for March 6th

Radio Technology Theme Crossword Puzzle for March 6th, 2022 - RF CafeThis custom made crossword puzzle for March 6th, 2022, from RF Cafe has a radio technology theme. 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 puzzle 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...

Thanks to everythingRF for Their Long-Time Support!

everything RF Searchable Database - RF CafePlease take a few moments to visit the everythingRF website to see how they can assist you with your project. everythingRF is a product discovery platform for RF and microwave products and services. They currently have 267,269 products from more than 1397 companies across 314 categories in their database and enable engineers to search for them using their customized parametric search tool. Amplifiers, test equipment, power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers, power supplies, and everything else. Please visit everythingRF today to see how they can help you.

Friday the 4th

Radio Circuit Page Schematics & Parts Lists

Radio Circuit Page, June 1948 Radio News - RF CafeHere are six more schematics and parts lists for radio models current when the June 1948 issue of Radio News magazine was published. Included are the Mantola Models 92503 and 92504, the Emerson Model 508 Series 8-7434351 and Up, the Belmont Model A-5D118, the Wards Model 74BR-2707A, the Crosley Model 56TP-L, and the Admiral Model 7C60 Chassis 6B1. Of course all use vacuum tube for signal and DC power amplification and rectification. Many of the electronics magazines of the era posted these as a service to repair shops and fix-it-yourselfers who did not have access to manufacturers' technical data. A lot of the companies would sell service information only to licensed sales and service shops...

Microwave Metasurface Reconfigured Using Stepping Motors

Microwave Metasurface Reconfigured Using Stepping Motors - RF Cafe"A metasurface that can be reconfigured using electric motors has been designed by researchers in the US and China. The structure can be programmed in real time to control impinging electromagnetic waves and was developed by a team led by Weili Zhang at Oklahoma State University. The metasurface comprises an array of dielectric 'meta-atoms,' which can be reoriented in groups. The set-up enabled the team to use the device to perform three very different tasks that involved manipulating microwaves. Metasurfaces are ultrathin films that comprise arrays of tiny dielectric structures that behave much like atoms - hence they are called meta-atoms. The meta-atoms are separated by distances smaller than the wavelengths of incoming electromagnetic waves. The result is a modification of the amplitude, phase and polarization of incoming wavefronts..."

Operation Chaos by Carl Kohler

Operation Chaos by Carl Kohler, June 1956 Popular Electronics - RF CafeCarl Kohler has done it again with his saga of a DIYer-gone-overboard titled "Operation Chaos," as it appeared in a 1956 issue of Popular Electronics magazine. Nobody knows for sure whether the over-enthusiastic husband in the series of techie stories that ran in Popular Electronics magazine in the 1950s was actually Carl himself or maybe an alter ego version of himself. Carl was also the artist of numerous tech-related comics. His wife, affectionately referred to as "Old Big Eyes" and a certified "lady-telepath" is always quick to recognize the impending disaster about to ensue, often with her as an unwilling participant. This particular project is not one recommended for the undertaking by anyone within eyeshot since aside from being profoundly unsafe, these days it would likely illicit a visit by a child welfare and/or animal rights Gestapo agent, accompanied by a police officer. The "Kohler Stroller" (which might be a hint as to whether this is about Carl himself) was actually an early version of today's wide selection of battery-powered toy cars and carts for tykes...

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!

Aegis Intros AC-DC Power Supplies for Ground Defense Applications

Aegis Power Systems Intros AC-DC Power Supplies for Ground Defense Applications - RF CafeAegis Power Systems, a leading supplier of AC−DC and DC−DC power supplies for custom and special applications, is pleased to announce the release of two new AC−DC power supplies for ground vehicles and other defense applications. Both the AP14G02K0282 and the AP14G01K2282 offer single phase 85-264 Vac input and 28 Vdc output. These power supplies are suitable for harsh environments with IP68 waterproof enclosure, humidity rating up to 95%, and ability to withstand extreme temperatures. Further, they have been tested for MIL-STD-810G and MIL-STD-461F for ground applications such as military vehicles, battery chargers, radars, naval equipment, and other similar defense applications. With a power factor of 0.99 at 115 Vac, these units are designed to support demanding electrical requirements with high efficiency and conditioning. The AP14G02K0282 offers 2000 W power and the AP14G01K2282 offers 1200 W. Both units provide good thermal performance through convection cooling, no need for external or internal fans...

Y(oung) L(ady) News and Views

YL News and Views, November 1953 QST - RF CafeFinding current information on the ARRL's Brass Pounders League (BPL) is difficult, and in fact a search on the ARRL.org website does not get you to a page with a date more recent than around 2012. I don't know whether the BPL has been "obsoleted" or just does not enjoy the promotion level it once did. This article in The Dipole publication reviews a bit of the history of the Brass Pounders League, and even mentions Mary A. Dougherty (a.k.a Mae Burke, W3CUL), who is featured in this 1953 QST article. She was born in 1911 and became a Silent Key in 1997. If I wasn't so busy, I would do some research to find out what the percentage of licensed female Hams was in 1953 compared with today. I wouldn't be surprised if the number was higher in 1953...

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 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.

Thursday the 3rd

Bell Telephone Laboratories - Germanium Crystal

Bell Telephone Laboratories, January 1954 Radio-Electronics - RF CafeAccuse me of whatever you want, but I sure wish a lot of the early and middle 20th century stalwart industrial and technology companies were still around. Some exist as a remnant of their former selves after having been absorbed into some other company - often a foreign concern. Others have been broken into separate parts with new names (e.g., Hewlett Packard into HP & Agilent/Keysight) while losing their founding identities. A few have retained their name (or part of it) while being owned and managed by foreign companies. Bell Systems is probably the poster child and most famous company forced to surrender its identity due to a court-ordered breakup following a monopoly lawsuit. As I have mentioned many times before, Bell is responsible for America's dominance in telecommunications in the 20th century. In this 1954 issue of Radio−Electronics magazine announces Bell Telephone Labs' development of ultra pure germanium crystals for fabricating semiconductors...

Trapped Ions Share a Wired Connection

Trapped Ions Share a Wired Connection - RF Cafe"Scientists at the University of California, Berkeley have persuaded two trapped ions to interact over a distance of 620 µm - much larger than would be possible via their intrinsic interaction - by connecting them with a room-temperature wire. This proof-of-principle experiment provides a pathway to more precise measurements of fundamental physics based on long-distance interactions between trapped particles. Trapped-ion technologies are an incredibly useful tool in physics. They are a leading candidate to build the quantum bits, or qubits, that make up quantum computers because ions are relatively easy to isolate and high-fidelity gate operations can be performed by the relatively simple means of shining laser light on the ions. Trapped ions are also used to make ultra-precise measurements of fundamental physics, for example in a recently-developed trapped-ion sensor that might prove useful...

FM Receivers and Their Alignment

FM Receivers and Their Alignment, August September 1940 National Radio News - RF Cafe1940 was a big year in the commercial broadcast industry because it was when the FCC began licensing stations for FM operation. Amazingly, that was only four years after Edwin Armstrong first came up with his frequency modulation scheme - fast moving for the government. Simultaneously, equipment manufacturers were cranking out transmitters, receivers, antennas (new frequencies), writing installation and operation guidelines, training servicemen, and doing scores of other vitally important tasks. The advent of FM was considered a very significant technical improvement because of immunity to electrical noise interference. If for no other reason, you should look at this National Radio News magazine article to see the photo of the megavolt artificial lightning discharge created to test and demonstrate FM's tolerance of such phenomena...

The Graphics Chip Chronicles

The Graphics Chip Chronicles - RF CafeIf you have been working with computers since the mid- to late 1980s, then you have witnessed an amazing evolution of graphics presentations for hardware, software, and firmware. 16-color, 320x200-pixel CGA monitors were at one time considered a great leap forward in the basic user interface compared to monochrome. Those green glowing blocky alphanumeric displays seen in 1970s and 80s TV shows and movies were avant-garde at a time not so really long ago. Per this Electronic Design website article, "Jon Peddie has put together short overviews of graphics chips that have made a major impact over the years. It is a fun look back at how we got to where GPGPUs are the norm." You might enjoy the trip down memory lane either from personal experience of vicariously through Mr. Peddie's...

Challenges in Early Automotive Radio Design

Challenges in Early Automotive Radio Design - RF CafeEarly automobiles presented significant challenges to mobile radio designers due to a combination of a fledgling understanding of electrical and electronic circuits and quickly evolving automotive materials and configurations. A 1935 issue of Radio-Craft magazine presented eight radio designs that represented break-through techniques for dealing with some of those innovations. All of the technical issues involved here have been pretty much solved in modern radios. Ignition interference is nearly invisible to FM and satellite reception, although audio frequency circuits can still pick up noise if not properly filtered and wired. Only dinosaurs like me still listen to AM broadcasts in the car and still hear occasional interference. Front end sensitivities and antenna design and placement have greatly extended reception range, although multipath, particularly in urban areas, is probably worse now than in the 1930s because there are vastly more sources of signal reflection. All of the radios, as did the Emerson 5A automotive radio, employed some sort of electromechanical DC-DC converter scheme in order to obtain the couple hundred volts needed to bias vacuum tubes from the car or truck 6-volt electrical system...

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...

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.

Wednesday the 2nd

Modelithics COMPLETE+3D Library v22.0 for Ansys HFSS

Modelithics Releases COMPLETE+3D Library™ v22.0 for Ansys HFSS - RF CafeModelithics is pleased to announce the release of version 22.0 of the COMPLETE+3D Library for use with Ansys HFSS. Included in this library are nearly 360 highly scalable Microwave Global Models™ for capacitor, inductor, and resistor families from many popular vendors. Also included is Modelithics' collection of over 500 3D electromagnetic (EM) geometry models for inductors, capacitors, filters, packages, and connectors. With both circuit and 3D EM models, the Modelithics COMPLETE+3D Library now represents a total of more than 24,500 individual components. Version 22.0 adds new Microwave Global Models for various part families, including the AMOTECH A60Z and A60L capacitor series and the Coilcraft 0201HL inductor series. New Microwave Global Models are also available for the Kyocera-AVX 08051C capacitor series and the Yageo CQ0201 and CQ0402 capacitor series. Additional new Microwave Global Models are available for part families from KEMET, TDK, and Würth Elektronik...

Electronics Themed Comics, August 1945 Radio-Craft

Electronics Themed Comics, August 1945 Radio-Craft - RF CafeHere are four more comics from magazines of the days of yore, in this case way back to 1945 (only 3 years before I was born - yikes!). Evidently Radio−Craft readers would submit ideas for funnies and then artist Frank Beaven would draw the comics. For some of them you need to be a little familiar with situations of the era, but usually you can discern what is going on anyway. An exception might be the first one here from page 712, where you need to know that a special "cat's eye" or "magic eye" vacuum tube was used in some radios to indicate how close you are tuned to the band center for a station. I particularly like the one here with the radio aerial stretched between the two teepees. It is rare to find a comic in a technical or hobby magazine these days. I don't know why that is. Enjoy...

The Benefits of Bidirectional Power Supplies

Axiom Test Equipment Blog: Believe in the Benefits of Bidirectional Power Supplies - RF CafeAxiom Test Equipment, an electronic test equipment rental and sales company has published a very unique and helpful new blog post entitled "Believe in the Benefits of Bidirectional Power Supplies." A bi-directional DC power supply makes it possible to evaluate how changes on supply voltage, current, or power affect the performance of a device under test. A bidirectional DC power supply is often used in CV or CC mode to simulate a rechargeable battery for a device under test, to better understand how a device or circuit will operate when its voltage fluctuates or drops below its nominal operating current or power level. With its bidirectional capabilities a regenerative DC power supply simplifies testing of such components as motor inverters, batteries, bidirectional on-board chargers (BOBCs), and bidirectional DC-to-DC converters without having to switch connections when testing the reverse current as with a conventional DC power supply...

Capacitor Function Quiz

Capacitor Function Quiz, March 1962 Popular Electronics - RF CafeThis Capacitor Function Quiz appeared in the March 1962 issue of Popular Electronics magazine. You can mentally substitute semiconductor diodes and transistors in place of the vacuum tubes is needed to figure out what role the capacitor plays in the circuits. Many of the configurations and function names are unfamiliar in today's design environment, but with some imagination you can probably figure out most of them. That said, I won't embarrass myself by telling you what my score was...

Horse Farm Property for Sale in Greensboro, NC

Horse Farm Property for Sale in Greensboro, NC - RF Cafe Cool ProductA lot of people are desiring to leave the city and suburb environment with ever-increasing crime rates and exorbitantly high taxes. If for that or any other reason you or someone you know is considering buying a country home with horse facilities, please take a look here. Located in a quiet area about 10 miles from Greensboro, NC, you will find that an affordable, comfortable, convenient, safe family life is still possible! My daughter, Sally, has decided to put her horse farm property up for sale. She built a very successful horse riding, training, and boarding business - Equine Kingdom - around it from the ground up over a period of eleven years. Due to a debilitating back injury, she can no longer perform the duties and maintenance necessary to sustain the operation. Formal lessons and long-term boarding ceased at the end of 2021, and now the entire property is being offered as a private home with extensive horse facilities. Of course you could re-establish it as a fully outfitted income-producing business with on-property living. At the time Equine Kingdom closed, Sally had more than 80 students and 5 part-time instructors...

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!

Please Thank IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products (IPP) has over 35 years of experience designing & manufacturing RF & microwave passive components. Their high power, broadband couplers, combiners, resistors, baluns, terminations and attenuators are fabricated using the latest materials and design tools available, resulting in unrivaled product performance. Applications in military, medical, industrial and commercial markets are serviced around the world. Products listed on website link to detailed mechanical drawings that contain electrical specifications as well as performance data. Please take a couple minutes to visit their website and see how IPP can help you today. 

Tuesday the 1st

The Transformer

The Transformer, October 1960 Popular Electronics - RF CafeIf you are looking for a very thorough treatise on transformers, from AC line frequency up through audio and RF frequencies, but without a lot of formulas to distract you, then this article by Ken Gilmore is it. He begins with the fundamentals of a current setting up a magnetic field, talks about mutual coupling and induction, step-up- and step-down transformers, autotransformers, iron and laminated core transformers, multi-tap voltage and impedance matching transformers, and even touches on the mage-size transformers in electrical distribution system substations. Transformers fundamentally work the same way today as they did when first invented in the 1830s. Equations for simulations have been refined to the nth degree, but for the vast majority of mankind this article will suffice to provide a better-than-a-layman's knowledge of the principles...

World's Smallest Battery Size of Grain of Salt

World's Smallest Battery Size of Grain of Salt - RF Cafe"Computers are getting smaller and smaller, just as current cell phones offer computing power similar to that of a laptop. And the trend toward miniaturization continues. Smart Dust applications (tiny microelectronic devices), such as biocompatible sensor systems in the body, demand computers and batteries smaller than a dust mote. So far, this development has been hindered by two main factors: lack of on-chip power sources for operation anytime and anywhere and difficulties in producing integrable microbatteries. In the current issue of Advanced Energy Materials, Prof. Dr. Oliver G. Schmidt, head of the Professorship for Material Systems of Nanoelectronics and Scientific Director of the Center for Materials, Architectures and Integration of Nanomembranes (MAIN) at Chemnitz University of Technology, Dr. Minshen Zhu, who has been working..."

Crossword Puzzle, March 1962 Popular Electronics

Electronics Crossword Puzzle, March 1962 Popular Electronics - RF CafeBeing an old-school old guy (turn 64 this year), I still work the crossword puzzle in the daily newspaper - surely you've heard of antiquated print media form of which I am the only house on my street which has it delivered daily. I also like the cryptogram type word jumble puzzles. Working the Sudoku puzzles is also a pencil and paper exercise (as opposed to interactive online) because of my method of figuring out the numbers. My older sister is a whiz at them, and she does them on her iPhone. Old habits die hard, as the saying goes. But I digress. In addition to the weekly RF Cafe Engineering and Science crossword puzzles I create each week, I also like to post crosswords that appeared in the vintage electronics magazines. This one appeared in the March 1962 issue of Popular Electronics...

RF & Electronics Symbols for Visio

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

Many Thanks to Bittele Electronics for Continued Support!

Bittele Electronics PCB Fabrication - RF CafeSince 2003, Bittele Electronics has consistently provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly services. It specializes in board level turnkey PCB assembly for design engineers needing low volume or prototype multi-layer printed circuit boards. Free Passive Components: Bittele Electronics is taking one further step in its commitment of offering the best service to clients of its PCB assembly business. Bittele is now offering common passive components to its clients FREE of Charge.

   

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