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Homepage Archive - July 2021 (page 1)

See Page 1 | 2 | 3 | 4 of the July 2021 homepage archives.

Wednesday the 7th

National Union Radio and Electronic Tubes

National Union Radio and Electronic Tubes, September 1944 Radio News - RF CafeIn 1944 when this National Union Radio Company ad appeared in Radio News magazine, the price of gold bullion was $35 US per ounce, as established by the Bretton-Woods Agreement. Inflation remained near zero until 1971 when President Nixon removed the U.S. treasury notes (dollars) from the gold standard. Take a look at the inflation chart in the background of the RF Cafe header (top of page) to see what has happened since then. Today's spot gold bullion price is around $1800 per ounce - a factor of 51x higher. According to the Bureau of Labor Statistics' Inflation Calculator, $35 in 1944 had the equivalent purchasing power of $538 today - a factor of 15x. That means the inflation-adjusted price of gold is about 3x what it was when National Union decided to use it to plate the wire control grid of its high power vacuum tubes in order to minimize performance-degrading grid emissions. Because relatively little gold would have been used...

What Does My Overheated Transmission Have to Do with Admiral Grace Hopper?

What Does My Overheated Transmission Have to Do with Admiral Grace Hopper?r, Kirt's Cogitations #330 - RF CafeLast week Melanie and I drove down to Greensboro, North Carolina, to attend our daughter's wedding. The weather was typically hot there, but not out of the norm. All went well at the small ceremony. Both bride and groom showed up, as did the minister and necessary witnesses. After the blessed event was over, we headed back northward to our humble abode in Erie, Pennsylvania. Our route upon exiting NC is I81 for a few miles in Virginia, then north onto I77, up to Rt. 19, then I79 all the way home up and down mountains for a few hundred miles. Our 2011 Jeep Patriot has never had any mechanical issues, but then it only has 81k miles on it and is kept in the garage. That day, though, the transmission overheating idiot light illuminated while on I81 - not a particularly hilly stretch. The outside temperature there was about 80 °F. I had noticed a slightly higher pitch sound from it while going uphill, but didn't think anything of it until the light came on. (On−Trak Automotive Services)...

Coronal Mass Ejection (CME) Interruptions

Coronal Mass Ejection (CME) Interruptions - RF Cafe"Humans have effectively created continent-size antennae - all exquisitely tuned to soak up currents caused by space weather" - John Kappenman of Storm Analysis Consultants, re the vulnerability of our massively networked electrical supply grids. He was quoted thus in the July 2012 edition of Popular Mechanics in an article entitled "Welcome to the Next Solar Maximum." Activities on our sun can effect profound consequences here on Earth, both in the form of communications disruptions and in the form of electrical supply grid disruptions. Both can be dire with the potential of crippling worldwide commerce. News agencies often refer to the violent spewing of copious quantities of high-speed electrons, protons, and neutrons as sunspot activity, but in fact, the phenomenon is termed coronal mass ejection (CME). Billion-ton belches of sun guts can be sent hurling earthward. Fortunately for us, not all CMEs are directed toward Earth, but enough do that NASA and the DoD...

Electronic Test Equipment Calibration Technician Needed

/2021/Axiom-Test-Equipment-Calibration-Technician-7-1-2021.htm"> Electronic Test Equipment Calibration Technician Needed by Axiom Test Equipment - RF CafeAxiom Test Equipment, an electronic test equipment rentals and sales company headquartered in North County San Diego, currently has the need for an /2021/Axiom-Test-Equipment-Calibration-Technician-7-1-2021.htm"> Electronic Test Equipment Calibration Technician. We are looking for an experienced, dedicated and ethical electronic calibration technician to help support our team. Do you want to work in a low-stress calibration lab, Monday through Friday, with no on-sites? Would you prefer to be treated as a person and not a number? If you have experience calibrating RF/Microwave, GPTE, and high-power test equipment, come talk to us about joining our team in Vista California. General Description: To calibrate both customer-owned and Axiom-owned electronic test equipment by performing one or more of the following: calibration, installation of options, troubleshooting, refurbishing, maintenance of electronic test and measurement equipment. Assist salespeople, customers...

New for 2021! 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 object has been built to fit proportionally on the provided A-, B- and C-size drawing page templates (or can use your own). Stencils 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 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.

Tuesday the 6th

Women Radio Commandos

Women Radio Commandos, September 1944 Radio News - RF Cafe"Those who cannot remember the past are condemned to repeat it." That line from George Santayana's The Life of Reason: Reason in Common Sense always comes to mind whenever I see articles from vintage publications about how people at the time were being forced to defend their ways of life from maniacal would-be dictators who marshaled armies of like-minded crazies to invade and attempt to subdue other countries and/or citizens within their own borders. It seems after a generation or two of comfortable, relatively safe existence, the collective guard is lowered and the hard-lessons from history are forgotten or subversively erased from memories. This particular 1944 Radio News magazine article tells the story of women of European Allied nations - in particular Polish women - taking up arms against Axis powers (Germany and Italy) during World War II. Part of the survival effort included learning to operate and service communications equipment in order to provide surveillance and security both on the battlefield and in helping countrymen escape the incursion. Some were captured...

Many Thanks to LadyBug Technologies for Their Continued Support!

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

Football Field-Sized Satellite Ends Operations

Football Field-Sized Satellite Ends Operations - RF Cafe"With booms spreading almost the length of a football field, the Air Force Research Laboratory's Demonstration and Science Experiments spacecraft is the largest self-supporting satellite ever placed on orbit. Last month, nearly two years after it launched and a year after its mission was expected to end, AFRL decommissioned the satellite. Although the DSX satellite launched in 2019, work on the experiment actually began in 2003. AFRL wanted to conduct research on the harsh radiation environment of medium Earth orbit, defined as the massive space between 1,243 miles and 22,236 miles above sea level. Emissions from the Van Allen radiation belts in MEO are particularly challenging and can damage satellites..."

Vintage Heathkit HW-8 QRP Transceiver Kit

Vintage Heathkit HW-8 QRP Transceiver Kit - RF Cafe Cool ProductThis vintage Heathkit HW−8 QRP Transceiver kit is one of the latest unbuilt Heathkit kits which appeared today on eBay - a fitting subject for the "Why Key Clicks?" article below.. I have been saving the images in order to preserve the history. The constantly growing list is at the lower right. The HW−8 covers the 80-, 40-, 20-, and 15−meter bands for CW. As you can see from the video at the bottom of the page, there were a lot of parts in the kit to assemble. The first instance I could find for HW−8 being offered for sale was in the Spring 1976 Heathkit catalog (p79), at a cost of $129.95 ($623.56 in 2021 money per the BLS). From the Spring 1976 Heathkit catalog: "We've made the world's most popular low-power CW transceiver even better! To the Heathkit HW-7 - we have added more bands, more features and a super new receiver section that's the best in its class. The famous HW-7 QRP Transceiver helped thousands of hams work the world on a couple of watts - and on a budget. Now, in the same value conscious tradition, Heath announces the HW-8...

Why Key Clicks?

Why Key Clicks?, October 1966 QST - RF CafeWaveform shaping is essential in today's crowded communications spectrum. Spectral masks are precisely defined in order to prevent "spreading" beyond the allocated frequency ranges at defined power levels. Whenever anything other than a continuous sinewave is being broadcast, there is spectral content generated in addition to the fundamental frequency. A Fourier transform of the waveform reveals which frequencies at what power levels comprise the waveform. The CW signal used by Morse code operators is a pure sinewave (or nearly so), but there is a spectral problem with it every time the signal turns on or off because of the square-ish edges involved during switching. RC networks are used in the transmitter circuits to tame the edges so that they do not turn on and off so quickly and in doing so reduce the extraneous frequency content. Author George Grammer argues that even though the signal could theoretically be made "clickless" (aka "chirpless"), there is an auditory benefit to the clicks or chirps that aids operators listening to high speed code transmissions...

New for 2020! 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...

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.

Monday the 5th

The Saga of the Vacuum Tube

The Saga of the Vacuum Tube, September 1944 Radio News - RF CafeThis is Part 13 of a series entitled "The Saga of the Vacuum Tube," by Gerald Tyne, that appeared in Radio News magazine in 1944. Part 1 was printed in March 1943, and Part 22, the final chapter, was published in April 1946. It could have been a stand-alone book. If I manage to be able to buy issues with some of the other parts, those will be posted as well. You might be aware of the origins of the amplifying vacuum tubes, beginning with the accomplishments of Dr. de Forest and his Audion. As with most new technologies, progress moved very rapidly once other researchers glommed on to the concept. Here, Mr. Tyne discusses the development of the "Kenotron," "Pliotron," "Dynatron," and "Magnetron," by Drs. Langmuir, Dushman and Hull of the General Electric Laboratories, during the years 1913 to 1921...

Noise Figure  <-->  Noise Temperature Calculator

Noise Figure  <-->  Noise Temperature Calculator - RF CafeThis JavaScript calculator converts between noise figure and the equivalent noise temperature. Just what is noise temperature and why is it used? Simply put, noise temperature is the temperature at which a resistor at the component / system input would generate the same amount of noise measured at the output. It goes back to the familiar kTB calculation for thermal noise power. Noise temperature is often used in calculating the overall noise figure of a system that includes an antenna at the input. That is because strictly speaking, a 1-port device like an antenna cannot be defined in terms of noise figure...

Spectrum Analyzers Check 5G Occupied Bandwidth

Axiom Blog: Spectrum Analyzers Check 5G Occupied Bandwidth - RF CafeAxiom Test Equipment, an electronic test equipment rental and sales company, has published a new blog post entitled "Spectrum Analyzers Check 5G Occupied Bandwidth" that informs people on how the right spectrum analyzers can help locate the interference of additional signal energy that can interfere with 5G service. With a suitable spectrum analyzer, occupied bandwidth measurements reveal the total integrated all signal energy within the bandwidths that concern 5G system designers, service providers, and users and when any interfering signals are at high enough power levels to be a concern. Selecting a spectrum analyzer for occupied bandwidth testing is a matter of matching the equipment's capabilities to the limits of the OBW measurements. An analyzer's frequency range and amplitude range are good starting points for 5G OBW measurements...

Backscatter Radio at Gigabit Speeds

Backscatter Radio at Gigabit Speeds - RF Cafe"Backscatter radios encode data in reflected signals to offer wireless communications that consume as little energy as possible - but they can be limited by poor data rates. Now scientists at Nokia Bell Labs and their colleagues have developed backscatter radios capable of gigabit speeds, for potential use in the emerging Internet of Things and other devices, a new study finds. Whereas conventional radios generate their own signals, backscatter radios transmit data by making tiny changes to reflected signals. This approach requires a minimal number of active components, promising simple low-cost battery-free operations. However, the low frequencies that backscatter radios often employ and the strategies they use to encode data in reflected signals typically limit their data rates..."

How to Select RF Chokes

How to Select R.F. Chokes, May 1966 Electronics World - RF CafeWirewound inductors (as most are) can be mysterious entities even when you are familiar with their many interdependent physical and electrical properties. Because of interwinding capacitance and a sometimes (when a large number of turns are involved) rather significant series resistance, the equivalent circuit model gets quite complex - literally in a mathematical sense. If you have the luxury of staying far away from the self-resonant frequency (SRF) of the coil, your component will behave very much like an ideal inductor, that is, XL = 2πfL. This 1966 Electronics World magazine article delves into what causes inductors to act like parallel and/or series resonant tank circuits, how to avoid the inconvenience of unwanted resonances, and how to exploit resonances in your favor. You'll also learn (if you don't already know) the distinction between a "choke" and an inductor...

Please Thank IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products (IPP) has over 30 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. Please take a couple minutes to visit their website and see how IPP can help you today.

Sunday the 4th

The Declaration of Independence...

The unanimous Declaration of the thirteen united States of America...because it is important to remember what is actually in it - not just what the Public Schools teach about it::: "In CONGRESS, July 4, 1776. The unanimous Declaration of the thirteen united States of America, When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation. We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness..."

Radio Theme Crossword Puzzle for July 4th 

Radio Theme Crossword Puzzle for July 4th, 2021 - RF CafeThis Radio Theme Crossword Puzzle for July 4th has a few words paying homage to what remains of the freedoms and promises of America, along with 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!

Please Thank Lotus Communication Systems for Their Support!

Lotus Communication Systems Modular RF/Microwave Components - RF CafeLotus Communication Systems began in 2009, setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex Country, Massachusetts. Lotus is committed to highest quality and innovative products. Each RF/microwave module meets exceedingly high standards of quality, performance and excellent value, and are 100% MADE IN USA. Lotus' RF/microwave products cover frequency band up to 67 GHz. Lotus also offers an COTS shield enclosures for RF/microwave prototyping and production. All products are custom designed. We will find a solution and save your time and cost. Lotus has multiple 4 axis CNC machines and LPKF circuit plotters.

Friday the 2nd

Mac's Radio Service Shop: Dog Day Discussions

Mac's Radio Service Shop: Dog Day Discussions, August 1952 Radio & Television News - RF CafeThe Dog Days of Summer run from July 3rd through August 11th. In fact, they begin tomorrow (as of when this is being written). John Frye usually wrote his monthly Mac's Radio Service Shop technodramas to correspond with the month - at least the season - in which it was published, so "Dog Day Discussions" is aptly placed in the August 1952 issue of Radio & Television News magazine. This episode dealt with how some TV manufacturers were dealing with the relatively new technology as the sets were being ravenously consumed by householders. Owners in fringe areas with weak signals or signals experiencing a lot of multipath interference were registering complaints about their very expensive television delivering poor performance. One response was to issue retrofit kits to service shops for peaking reception sensitivity while filtering out nearby out-of-band noise. In those days you didn't simply throw out your old TV or radio and buy a new one. An interesting phrase...

2D Transistors for Tinier Microchip Components

2D Transistors for Tinier Microchip Components - RF CafeAtomically thin materials are a promising alternative to silicon-based transistors; now researchers can connect them more efficiently to other chip elements. Moore's Law, the famous prediction that the number of transistors that can be packed onto a microchip will double every couple of years, has been bumping into basic physical limits. These limits could bring decades of progress to a halt - unless new approaches are found. One new direction being explored is the use of atomically thin materials instead of silicon as the basis for new transistors but connecting those '2D' materials to other conventional electronic components has proved difficult..."

Exodus Intros 6 to 10 GHz, 100 W SSPA

Exodus Advanced Communications Intros 6 to 10 GHz, 100 W SSPA - RF CafeExodus Advanced Communications, a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide, introduces the AMP2053A−1. Model AMP2053A−1 is a rugged solid state power amplifier (SSPA) replacing aging TWT technology. It is a broadband class A/AB amplifier design for all industry standards, with a wide 6.0-10.0 GHz bandwidth, a minimum power output of 100 W Minimum (>120 W typical) and 50 dB of gain. The SSPA features excellent power and gain flatness as compared to TWT's. Forward and reflected power monitoring, VSWR, voltage/current and temperature sensing are provided for superb reliability and ruggedness. The nominal weight is 45 lbs. in a compact 4U chassis, 7"H x 19"W x 22"D...

Roll Your Own Capacitors

Roll Your Own Capacitors, January 1956 Popular Electronics - RF CafeHere is another instance that shows how much expectations have changed over the years. Except maybe for an experimenter or someone set on reproducing original equipment as closely as possible, nobody would even consider trying to build capacitors from scratch. Compared to when this "Roll Your Own Capacitors" story appeared in a 1956 issue of Popular Electronics magazine, components nowadays are so inexpensive that it's just not worth the trouble. If you are one of the extreme do-it-yourself type people, then this story is for you. Come to think of it, another use for this article is to provide material for a physics class laboratory exercise where the student calculates a predicted value for capacitance based on surface area, dielectric constant, and plate separation distance...

Tomorrow, July 3, Marks the Beginning of The Dog Days of Summer

The Dog Days of Summer - RF CafeThe Dog Days of Summer, contrary to what many people believe, is named not to describe the hottest, most humid, most oppressive period of the year, but marks the astronomical point in time following the heliacal rising of the star system Sirius, aka the Dog Star in the constellation Canis Major. 40 days later, on August 11th, the Dog Days end. That also happens to be middle of summer (not midsummer), which is on or about August 6th. Never having been a proponent of summer, the end of the Dog Days has always meant we're closer to the end of summer than to the beginning, and autumn is on the way.

RF Cascade Workbook 2018

RF Cascade Workbook 2018 Is Available Now! - RF CafeRF Cascade Workbook 2018 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 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.

Thursday the 1st

Tiny Tube Steals Transistor's Thunder

Tiny Tube Steals Transistor's Thunder, August 1958 Radio-Electronics - RF CafeMany people in the electronics realm - both producers and consumers - were reluctant to let go of their dearly beloved vacuum tubes and adopt the newfangled semiconductor components. To be honest, I likely would have been one of them based on my aversion to change. In 1958 when this "Tiny Tube Steals Transistor's Thunder" feature graced the cover of the August issue of Radio-Electronics magazine, the transistor was barely a decade old and could not yet operate at high temperatures, high frequencies, high voltages, or under rugged mechanical conditions. This particular miniature tube was the creation of GE, and soon thereafter RCA introduced their "nuvistor" to compete with transistors. History shows, of course, that the battle was handily won by the semiconductor industry, and we're better off because of it. Still, there's something about the soft orange glow of a vacuum tube in a darkened room that sets a mellow mood...

Chirped Pulses Defy "Conventional Wisdom"

Chirped Pulses Defy "Conventional Wisdom" - RF Cafe""The 2018 Nobel Prize in Physics was shared by researchers who pioneered a technique to create ultrashort, yet extremely high-energy laser pulses at the University of Rochester. Now researchers at the University's Institute of Optics have produced those same high-powered pulses - known as chirped pulses - in a way that works even with relatively low-quality, inexpensive equipment. The new work could pave the way for better high-capacity telecommunication systems, improved astrophysical calibrations used to find exoplanets, more accurate atomic clocks, precise devices for measuring chemical..."

Needed: Electronic Inventions

Needed: Electronic Inventions, January 1956 Popular Electronics - RF CafeI and others joke frequently about the promise of flying cars, automated homes, and miracle pills to cure any maladies that were predicted to be commonly available by the end of the 20th century. Magazines like Popular Science, Mechanix Illustrated, Science and Mechanics, et al, regularly printed stories about these and a host of other inventions that were just around the corner. Most have never been realized, but we're appreciative of the dreamers and those people who dedicated their lives - often to the point of financial and/or physical ruin - while trying to succeed. Taking a different approach, Edwin Lawrence, in this 1956 article in Popular Electronics, solicits readers to consider inventing a few 'needed inventions" that he throws out. Among them death ray that will incapacitate or kill at great distances, a speech-into-writing translator, a buried explosive detector, a 3-dimensional visual display, a device for recording television programs, and a handful of other ideas. Interested parties are bade to contact the National Inventor's Council...

Fixed Pi and T Attenuator Calculator

Fixed Pi and T Attenuator Calculator - RF CafeThis is a Javascript calculator for fixed Pi and T attenuators. Enter values for Rin, Rout, and Attenuation, then click Calculate. If unequal termination resistances are used and an attenuation value is selected that is lower than what is physically possible (a negative resistor value is displayed), then a message will appear in the box over the schematics. "k" is the linear ratio equivalent to the decibel value of the attenuator. Equations used in this calculator can be found on the Pi and Tee Attenuators Equations page...

New for 2021! 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 object has been built to fit proportionally on the provided A-, B- and C-size drawing page templates (or can use your own). Stencils 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...

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.

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