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Amplifier Solutions Corporation (ASC) - RF Cafe

Homepage Archive - March 2023 (page 4)

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

Friday the 31st

Thursday the 30th

Wednesday the 29th

Tuesday the 28th

Monday the 27th

Sunday the 26th

Electronics Theme Crossword for March 26th

Electronics Theme Crossword Puzzle for March 26, 2023 - RF CafeThis custom RF Cafe electronics-themed crossword puzzle for March 26th contains words and clues which pertain exclusively to the subjects of electronics, science, physics, mechanics, engineering, power distribution, astronomy, chemistry, etc. If you do see names of people or places, they are intimately related to the aforementioned areas of study. As always, you will find no references to numbnut movie stars or fashion designers. Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds of them dating back to the year 2000. Enjoy.

Many Thanks to Withwave for Long−Time Support!

Withwave RF & Microwave Components - RF CafeWithwave manufactures an extensive line of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch, board edge, panel mount), calibration kits (SOLT), a fully automated 4-port vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures for calibration and multicoax cable assemblies. Frequency ranges from DC through 110 GHz. Please contact Withwave today to see how they can help your project succeed.

Friday the 24th

Electronic Video Recording | Color TV

Electronic Video Recording | Color TV, February 1969 Radio-Electronics - RF CafeIn the pre-VHS era, companies were vying to create and set standards for the home-based video recording and playback industry. The same sort of scenario played out over color television standards a decade earlier, and over B&W television a couple decades before that. Such battles for dominance in emerging technologies were not new, and continue into the current time. Various schemes for Electronic Video Recording systems were being used by commercial media, but creating devices affordable to Harry and Harriet Homeowner was a challenge. Betamax, produced by Sony, hit the store shelves in 1975, then VHS a year later. A sort of 8-track vs. compact cassette battle ensued, but VHS clearly emerged as the winner - followed by DVD and Blu-ray. Also reported was the world's most expensive - and feature-filled - color TV, built by Philips, that was "more computer than television," being able to operate on eleven different modulation standards...

Carbon Nanotube Wiring on Plastic Films

Carbon Nanotube Wiring on Plastic Films - RF Cafe"Researchers at Tokyo University of Science have proposed a novel method to fabricate multi-walled carbon nanotube (MWNT) wiring on a plastic film under ambient conditions using a low-cost laser. The properties of Carbon nanotubes (CNTs) include high strength, low weight, and excellent thermal and electrical conductivities. This makes them suitable materials for applications including reinforcement materials, energy storage and conversion devices, and electronics. Despite their potential, it has proven challenging to incorporate them onto plastic substrates for fabricating flexible CNT-based devices. The breakthrough from Japan involves coating a polypropylene (PP) film with an MWNT film about 10μm thick and then exposing it to a mW UV laser. The result is a conductive wiring made of a combination of MWNT and PP. The research is detailed in Scientific Reports. This process enables the easy 'drawing' of wiring and flexible devices for wearable sensors without the need for complex processes..."

Belmont Model 5D128 Tabletop Radio

Belmont Model 5D128 Tabletop Radio, November 1946 Radio News - RF CafeThe Belmont model 5D128 was a compact, inexpensive tabletop AM radio set. A schematic and parts list for it appeared in the November 1946 issue of Radio News magazine. 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, so I scan and post them whenever they appear in magazines which I own. While researching the Belmont 5D128 tabletop radio, I ran across an excellent video created by Mr. Paul Carson, as part of his Mr. Carlson's Lab series (note how the setting looks like he's in the ISS). Here is a great video of Mr. Carlson troubleshooting an intermittent noise problem in a receiver. That "Carlson RF SuperProbe" he is using looks like a must-have piece of test equipment The Belmont 5D128 was rebranded by other companies such as Airline, Coronado, Lafayette...

IPP-5014, 30-1000 MHz Transformer

Innovative Power Products IPP-5014, 30-1000 MHz Transformer - RF CafeInnovative Power Products (IPP), with more than 30 years of experience designing & manufacturing RF & microwave passive components, Innovative Power Products introduces our model IPP-5014, a 100 watt surface mount single-ended transformer that operates from 30 to 1000 MHz. The IPP-5014 is a single-ended impedance transformer that operates from 30 to 1000 MHz with a 4:1 transformation ratio and 100 watt average power rating. The IPP-5014 transforms impedance from 50 ohms at J1 to 12.5 ohms at J2. The insertion loss is less than 0.75 dB from 30-50 MHz and less than 0.60 dB from 50-1000 MHz. The VSWR is less than 1.43:1. Single-Ended Transformers are used to match devices of differing impedances. Innovative Power Products can also customize our single-ended transformers to fit your project...

National Company: TMS Condensers

National Company Ad: TMS Condensers, March 1939 QST - RF CafeNational Company, an early manufacturer of electronics components for radio products, ran a series of unique advertisements in the ARRL's QST magazine. Rather than using precious cash for directly promoting specific products or product lines, company president John Millen occupied full pages with text explaining why it makes the things it does and how they can be used to solve problems or enhance performance. This article/ad on TMS condensers (aka variable capacitors) was number 61 in the series, which means if they printed one every preceding month, the first would have appeared in the March 1934 issue of QST...

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 Amplifier Solutions Corporation (ASC) for Continuing Support!

Amplifier Solutions Corporation (ASC) - RF CafeAmplifier Solutions Corporation (ASC) is a manufacturer of amplifiers for commercial & military markets. ASC designs and manufactures hybrid, surface mount flange, open carrier and connectorized amplifiers for low, medium and high power applications using Gallium Nitride (GaN), Gallium Arsenide (GaAs) and Silicon (Si) transistor technologies. ASC's thick film designs operate in the frequency range of 300 kHz to 6 GHz. ASC offers thin film designs that operate up to 20 GHz. ASC is located in an 8,000 sq.ft. facility in the town of Telford, PA. We offer excellent customer support and take pride in the ability to quickly react to evolving system design requirements.

Thursday the 23rd

Electronics News Briefs

News Briefs, April 1960 Radio-Electronics - RF CafeLots of interesting topics were reported in News Briefs from the April 1960 issue of Radio-Electronics magazine. One that is relevant even today is the assigning of new numeric prefixes tera for a trillion; giga for a billion; nano for a billionth, and pica for a trillionth. If you have read vintage science and engineering publications, you know that, for instance, what is now called pica (a la pF, 10-12) used to be written as micromicro (a la μμF, 10-6x10-6 = 10-12). Here is an example of μμF being used. Less commonly seen was something like millimicroamperes, which is 10-3x10-6 = 10-9, now known as a nanoamperes, nA. A new television picture tube which used a solid state electron emitter in place of a heated cathode was announced for portable TVs, potentially doubling battery life. Did you know that in 1960, the South African government felt that TV would be detrimental to children and "the less developed races," thereby justifying its anti-TV policies? Following on the results of the International Geophysical Year (IGY) discoveries, atmospheric ducts for radio signal transmission propagation were being found worldwide...

Accurate Multi-Channel Radar Signal Generation

Phase and Timing-Accurate Multi-Channel Radar Signal Generation - RF CafeEngineers at Berkeley Nucleonics Corporation (BNC) and AnaPico teamed up to write a paper entitled "Phase and Timing-Accurate Multi-Channel Radar Signal Generation." It begins: "Engineers testing radar require the ability to generate multi-pulse streams with each pulse supporting dozens of parameters such as frequency, amplitude, phase, pulse width, time position and intrapulse modulation or chirping. Table 1 summarizes the typical parameter set describing a single radar pulse, known as a pulse descriptor word (PDW). A list of PDWs will fully describe a radar pulse stream. Multi-patch radar antenna arrays require additional parameters for full characterization. For these arrays, inter-channel phase coherence, which addresses relative phase stability becomes important. Phase-coherent switching, where the relative phase between channels is stored in memory and inter-channel timing accuracy are also critical parameters..." A version of this article also appears on the MWJ website.

General Electric Germanium Transistors

General Electric Germanium Transistor Advertisement, November 1953 QST - RF Cafe"If you're not using transistors already, chances are you'll consider them for amplifiers and oscillators in future circuits." So says the line in an advertisement for General Electric vacuum-sealed transistors in a 1953 edition of QST magazine. To say the claim was prescient is an understatement. A lot of people resisted the switch to transistors for many years - especially hobbyists who had grown accustomed to working with vacuum tubes. Maybe GE figured pitching the newfangled devices as being "vacuum-sealed" would help the hardliners soften their opposition to them. Not mentioned in the ad is that these three transistors - the 2N43, 2N44, and 2N45 - are all germanium-based. It wasn't until May of 1954 that Texas Instruments (TI) announced the commercial availability of grown-junction silicon transistors...

Pulse Fidelity for High-Power GaN Radar and EW Tx's

Pulse Fidelity for High-Power GaN Radar and EW Tx's - RF CafeMicrowave Journal magazine has a useful article posted entitled, "Innovations in Pulse Fidelity for High-Power GaN Radar and EW Transmitters." Darren Miles and George Bollendorf, of Empower RF Systems and Bob Buxton, of Boonton Electronics team up to present a method for accurately measuring and compensating distortions in pulses driving the output stage. It begins: "Radar and electronic warfare (EW) have been the primary applications for extremely high-power transmitters, driving the demand for specialized high-power traveling wave tubes (TWTs) and magnetrons. Diminishing sources of TWT supplies, coupled with their poor reliability, inefficiency, large size and high total lifetime cost of ownership are causing a migration away from tubes. While improved pulse fidelity accompanies the shift to solid-state transmitters, next-generation radar depends on further improvements in waveform fidelity and flexibility. Next-generation radar systems utilize long pulse widths, which present specific challenges. In response, Empower RF Systems has developed technology to reduce pulse distortion as a development step towards pulse shape matching, allowing the reproduction of the input pulse without distortion. The pulse correction is performed within the amplifier in real-time. This is important because long pulse width radar is especially vulnerable to over/undershoot and droop...

When Your Phone Is Spying on You

When Your Phone Is Spying on You - RF Cafe"Smartphone spyware apps that allow people to spy on each other are not only hard to notice and detect, they also will easily leak the sensitive personal information they collect, says a team of computer scientists from New York and San Diego. While publicly marketed as tools to monitor underage children and employees using their employer's equipment, spyware apps are also frequently used by abusers to covertly spy on a spouse or a partner. These apps require little to no technical expertise from the abusers; offer detailed installation instructions; and only need temporary access to a victim's device. After installation, they covertly record the victim's device activities - including any text messages, emails, photos, or voice calls - and allow abusers to remotely review..."

Galvin Motorola Model 61 Automotive Receiver

Galvin Motorola Model 61 Automotive Receiver, October 1932 Radio-Craft - RF CafeWhat the heck is an Elkonode? That was my response to its mention in this Radio Service Data Sheet for the Galvin Motorola Model 61 Automotive Receiver. The Mallory-Elkon Elkonode was an electromechanical vibrator device for DC-DC conversion. An oscillating circuit opened and closed a set of contacts being fed with the automobile's DC supply, thereby creating a chopped waveform which was applied to a step-up transformer, then rectified and filtered to provide the high plate voltage for the radio's vacuum tubes. A Google search turned up a datasheet on the Mallory Elkonode. Per the info, "The series 60, 70, and 80 Mallory Elkonodes are described as single-reed, full-wave inverters, with self-contained synchronous rectifiers. These units within themselves supply direct current, high voltage for radio receiver plate supply. No tube rectifiers are required with these types." This 1932 Radio−Craft magazine article recommends against attempting self-repair of Elkonodes (aka interrupters), so restoration buffs will appreciate the instructions offered in the datasheet...

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 PCB Directory for Continued Support!

PCB  Directory - RF CafeThe leading website for the PCB industry. PCB Directory is the largest directory of Printed Circuit Board (PCB) Manufacturers, Assembly houses, and Design Services on the Internet. We have listed the leading printed circuit board manufacturers around the world and made them searchable by their capabilities - Number of laminates used, Board thicknesses supported, Number of layers supported, Types of substrates (FR-4, Rogers, flexible, rigid), Geographical location (U.S., China), kinds of services (manufacturing, fabrication, assembly, prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.

Wednesday the 22nd

What Happened at Oslo? Color TV

What Happened at Oslo?, January 1967 Radio-Electronics - RF CafeIt is kind of hard to believe that even by 1966, when the International Telecommunications Union (ITU) met in Oslo, Norway, that the world had not yet agreed in a common transmission standard for color television. In January of 1967, Radio−Electronics magazine editor Thomas Hasket interviewed two major players in the industry, George Brown of Radio Corporation of America (RCA), and Frederick M. Remley, Jr. of Society of Motion Picture and Television Engineers (SMPTE), regarding the stalemate that was unarguably hampering the ramping up of color television set production. Consumers were pining for them, but companies hesitated to invest engineering and manufacturing resources when they couldn't be sure it would not be thwarted by a change in the modulation scheme. A battle was being waged between the U.S. NTSC standard and the European PAL system (and SÉCAM to a lesser sense). Both had strengths and weaknesses, but history has shown, NTSC ultimately won. Possibly due to the impasse, color TV sales in America did not surpass B&W sales until the early 1970s...

Anatech Electronics March 2023 Newsletter

Anatech Electronics March 2023 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his March 2023 newsletter that features his short op−ed entitled "Healthcare Industry IoT Security Under Threat," which discusses some of the issues compromising not just healthcare privacy, but the whole Internet of Things (IoT) effort. The fact is your healthcare records have been anything but secure and private for a long time. The Health Insurance Portability and Accountability Act of 1996 (HIPAA), which is responsible for the glass or Plexiglas barriers with the small transaction opening installed at the reception desks at doctor and dentist offices, was supposed to make people feel that their medical history was being protected against prying eyes, physically and digitally. That has been as effective as requiring everyone to wear a cloth facemask to protect them against a virus. My guess is that nearly every form of personal information is available on the black market from databases breached by not just outside black-hat operators, but by government and private corporate employees seeking financial payouts. Information fences are fairly easily contacted if you seek such information. Consider how prolifically your e-mail and other non-medical information is made available to concerns with enough money to buy it...

Electronics Themed Comics

Electronics Themed Comics, March 1948 Radio-Craft - RF CafeHere are a four more technology-related comics from magazines of the days of yore, this time from a 1948 edition of Radio-Craft magazine. Readers would submit ideas for funnies and then artist Frank Beaven would draw the comics. The page 37 comic is an example. Evidently E.R. Donohue, of Walla Walla, Washington, had issues with his phonograph featuring a record changer mechanism. My interest in rockets makes me really appreciate the page 82 comic with the missile's flight being affected by the musical "interference." In the early days of remote control, audio tones modulated onto a carrier commanded tuning-fork-like (tuned) "reeds," which acted as channel filters for separating and directing signals, in the airborne receiver section to control surface actuators (see video). It is rare to find a comic in a technical or hobby magazine these days. I don't know why that is...

Making Money in Radio - Still Possible?

Making Money in Radio (Bob Davis) - RF CafeMike Simpson homebrew replacement electrolytic capacitor - RF CafeLong-time RF Cafe contributor Bob Davis sent me a link to this very interesting and entertaining story of one man's journey (Mr. Mike Simpson) in his effort to determine whether "Making Money in Radio" is still as guaranteed as the vintage electronics magazine advertisements enthusiastically asserted. To find out, he, researched and purchased a couple vacuum tube radios, then restored them to fine quality, and then put them up for sale on eBay. In some cases minor component replacement or repair was required. Calculations were then made of an estimated effective hourly wage for the effort. The result may (or may not) surprise you. As you will see on his "Analog Dial" website, Mike has collected and restored many old radios, both production models, kits from the era, and homebrew radios. BTW, notice in the photos that he's a model rocketeer as well. A bit of good humor is mixed in with the stories and descriptions. Enjoy!

Battery Types and Their Characteristics

Battery Types and Their Characteristics, April 1973 Popular Electronics - RF CafeAccording to Samuel Milbourne's "Battery Types and Their Characteristics" article in Popular Electronics magazine, in 1973 there were about 400 different battery types to choose from when deciding what to buy for your automobile, electronic device, uninterruptible power supply, flashlight, etc. I don't know what the number of types is today, but it must be in the thousands. Nominal voltage, case size and shape, energy capacity (amp-hour rating), current delivery capacity ("C" rating), environmental accommodation, connection type (contact, solder, screw-on, or push-on terminals), chemistry, number of recharge cycles (for secondary batteries), and a host of other choices are available nowadays. Every time I need to order a new Li-Po battery pack for a model airplane or helicopter, I spend quite a bit of time searching through mAh versus weight and physical size specifications to identify the best - and most affordable - option. There will never be a one-size-fits-all battery. If you are interested in vintage batteries...

RF Cascade Workbook

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

Please Visit Empower RF's Website in Appreciation of Their Support

Empower RF Systems - RF CafeEmpower RF Systems is the technological leader in RF & microwave power amplifier solutions for EW, Radar, Satcom, Threat Simulation, Communications, and Product Testing. Our air and liquid cooled amplifiers incorporate the latest semiconductor and power combining technologies and with a patented architecture we build the most sophisticated and flexible COTS system amplifiers in the world. Solutions range from tens of watts to hundreds of kilowatts and includes basic PA modules to scalable rack systems.

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Micro-Waves Span the English Channel

Micro-Waves Span the English Channel, September 1935 Short Wave Craft - RF CafeWe "Baby Boomers" remember a time when cell towers did not present a ubiquitous (and, frankly, ugly) presence across the landscape. Microwave relay towers for television and telephone links could be spotted sitting atop hilltops and mountain ridges in some areas, and giant television and radio station towers sat behind broadcast stations, and multi-element antennas dotted house rooftops everywhere. Our grandparents (Millennials' great grandparents) remember when even microwave relay towers were missing. This 1936 article reports on the first microwave links spanning the English Channel to replace expensive and trouble-prone submerged cable. Part of the impetus, not mentioned within, was the building inevitability of war with Germany and the vulnerability of those communications links to being compromised by Nazi submarines and divers...

Morse Code Rhythm Patterns from A to Z

Morse Code Rhythm Patterns from A to Z (QST April 2023) - RF CafeGiven that this "Morse Code Rhythm Patterns from A to Z" article (p58) appeared in the April issue of QST magazine, I was careful to ascertain that it was not written for fools. It seems authentic, but for the life of me I don't know how many people would find the proposed Morse Code learning system to be a natural method. Author Bill Cody (K3CDY) is a musician who is accustomed to reading music, so for him and other talented musical types, maybe such a system facilitates the learning of code. To people like me, it's like suggesting a method for more easily learning how to apply a bandage by adapting brain surgery principles. Unfortunately, you'll need to be an ARRL member for access to the online article, or maybe you can borrow a copy of the magazine from a friend (but you'll still need to sign in for the music/code sheets). I'm still trying to figure out which article is the April Fools bait. BTW, I remember using one of those Isolate Pad Circuit-Board Construction tools when making proto boards (p91).

Electronics Mathematics Quiz

Electronics Mathematics Quiz, June 1969 Popular Electronics - RF CafeDon't let the title scare you away from this "Electronic Mathematic Quiz." It appeared in the June 1969 issue of Popular Electronics magazine, and was created by quizmaster Robert Balin. There are no scary equations to complete and no mental calculations to bend your brain. Instead, the "mathematics" required is to recognize physical and electrical signal shapes which are described by common mathematics terms. For instance, a cardioid approximates the electromagnetic radiation pattern of many directional antennas, which may include a parabolic dish. Differentiator and integrator circuits generate distinct waveforms. Phase angles and critical angles are familiar to circuit designers and radio operators. Shape letter "E" will likely be familiar according to its name, although you might not know what it is in the world of electronics...

Howard Explorer Model W All-Wave Superhet

Howard Explorer Model W Deluxe 19 Tube All-Wave Superhet Radio Service Data Sheet, September 1934 Radio-Craft - RF CafeHere are the schematics, chassis layout, and service info for the Howard Explorer Model W Deluxe 19 Tube All-Wave Superheterodyne console style (sits on the floor) radio. The wooden cabinet format is somewhat unusual in that the top is a flat surface rather than the having more typical curvaceous lines that radios of the era sported. It looks a lot like the models with built-in phonographs, where the top would tilt upward. The Radio Service Data Sheets that were published in Radio-Craft usually seem to have more information included than those published in other magazines, at least in the same era (1940-ish). It might have to do with how much material is provided by the manufacturer rather than a decision by the magazine editors. This one appeared in the September 1934 issue. Believe it or not, there are still people searching for such data. I could not find an example of a real surviving Howard Explorer Model W radio...

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Superception

 

 

 

 

 

 

 

 

 

 

Potentially Damaging Black Hole Mass Ejection Approaching Earth Orbit

 

 

 

June 1969 P-E, Kohler p40, Math Quiz p46, I/O Impedances p69

July 1969 P-E, B-Quiz p64

August 1969, Hobnobbing Harbaugh p68

September 1969, Bridge Quiz p68

October 1969, Op Amp Quiz p58

 

 

Engineering Job Opening

Promote Your Company on RF Cafe

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

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...

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...

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!

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...

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...

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

Engineering Job Board - RF CafeRF Cafe's raison d'être is and always has been to provide useful, quality content for engineers, technicians, engineering managers, students, and hobbyists. Part of that mission is offering to post applicable job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge. 3rd party recruiters and temp agencies are not included so as to assure a high quality of listings. Please read through the easy procedure to benefit from RF Cafe's high quality visitors...

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Ultrathin Metasurface Display Rivals LCD

Ultrathin Metasurface Display Rivals LCD - RF Cafe"Currently, LCD screens are the most dominant and popular display technology for televisions and monitors, but they are unlikely to get significantly better in the future. Now a new study finds the kind of physics that make microscopic 'invisibility cloaks' possible may lead to next-generation 'metasurface' displays roughly 1/100 the thickness of the average human hair that could offer 10 times the resolution and consume half as much energy as LCD screens. LCD technology depends on liquid crystal cells that are constantly lit by a backlight. Polarizers in front and behind the pixels filter light waves based on their polarity, or the direction in which they vibrate, and the liquid crystal cells can rotate the way these filters are oriented to switch light transmissions on and off. LCD screens do continue to see advances by improving the liquid crystals, the display technology or the backlight. 'However, improvement on LCD technologies are now mostly just..."

EMI in Connected Vehicles

EMI in Connected Vehicles - RF Cafe"Automakers need to rein in electromagnetic interference before it pumps the brakes on in-vehicle connectivity innovations. In early 1979, Ralph Liuzzi installed a mobile transmitter in his customer's Cadillac Seville. However, Mr. Liuzzi found that whenever he attempted to transmit, the car's engine would stall, resulting in a serious safety hazard for both driver and pedestrians. At the time, the National Highway Traffic Safety Administration (NHTSA) cited a 'lack of documentation on the effects of Electromagnetic Interference (EMI) on automobile electronic engine control systems,' but reviewed the case and eventually found that indeed EMI played a key role in the system malfunction. 'The problem of EMI is a relatively new one in automotive technology since electronics have only recently been introduced into usage in automobiles,' the NHTSA said in its report. Now, more than 40 years later, the problem of EMI has only grown..."

IDTechEx Report on 6G Market 2023-2043

IDTechEx Report on 6G Market 2023-2043 - RF Cafe"IDTechEx, an independent market research and business intelligence provider claims that 6G will arrive in 2028 at the earliest in its recently published market research report, "6G Market 2023-2043: Technology, Trends, Forecasts, Players". 6G, compared to its predecessor, is expected to offer significantly better communication capabilities, such as Tbps-level peak data rates, microsecond-level latency, and 99.99999% network dependability. Although 6G promises a lot, it is unlikely that 6G will be in daily life soon, despite the fact that several important companies and nations have already begun 6G research, as shown in the figure below, the telecom industry needs to address several issues before seeing the success of 6G. The difficulties are not only in THz technology but also in identifying applications that will fuel 6G adoption. IDTechEx has been researching 5G and 6G for years. This article will discuss some of the hardware-related hurdles to 6G connectivity..."

Microsatellites Reduce Space Junk

Microsatellites Reduce Space Junk - RF Cafe"Satellite powered by 48 AA batteries and a $20 microprocessor shows a low-cost way to reduce space junk. Common sense suggests that space missions can only happen with multimillion-dollar budgets, materials built to withstand the unforgiving conditions beyond Earth's atmosphere, and as a result of work done by highly trained specialists. But a team of engineering students from Brown University has turned that assumption on its head. They built a satellite on a shoestring budget and using off-the-shelf supplies available at most hardware stores. They even sent the satellite - which is powered by 48 Energizer AA batteries and a $20 microprocessor popular with robot hobbyists - into space about 10 months ago, hitching a ride on Elon Musk's SpaceX rocket..."

Time Reflection Measured in Microwaves

Time Reflection Measured in Microwaves - RF Cafe"Physicists in the U.S. have observed an effect known as time reflection in an electromagnetic wave for the first time. They detected the phenomenon - the temporal counterpart of familiar spatial reflection - by rapidly switching a series of capacitors in a novel type of metamaterial. They say the result could improve wireless communication and ultimately help bring about long-sought-after optical computing. Everyday reflection involves the transformation of a wave packet when it meets an interface in a distinct region of space. The process preserves temporal ordering, so that the leading part of the incident wave remains ahead after reflection. This means that objects further from a mirror look more distant in the reflection, while sounds in an echo arrive back in the same order they were emitted. Time reflection instead involves a wave packet being transformed as a result of an abrupt change in time that applies equally throughout the medium it is traversing. In other words, the material in question experiences a sudden shift in its properties..."

 

 

 

 

 

 

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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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