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Homepage Archive - August 2020 (page 3)

See Page 1 | 2 | 3 | 4 | 5 | of the August 2020 homepage archives.

Friday 21

Mac's Service Shop: A Typical Day in the Shop

Mac's Service Shop: A Typical Day in the Shop, July 1955 Radio & Television News - RF CafeJust as the title of this installment of Mac's Service Shop, "A Typical Day in the Shop," suggests, the story is a recollection of the kinds of scenarios that would found in an ordinary shift in an electronics service business in the mid 1950's. Vacuum tubes were the norm of the day, as were discrete leaded components and a rat's nest of wires running from solder lug to solder lug. Printed circuit boards were beginning to appear in commercial products, but mostly existed in specialty defense and aerospace applications. You might wonder how many different ways could there be for simple circuits like biasing and heater element lighting, but some pretty imaginative variations made their way into radios, television, record players, and tape decks, and often times that made a serviceman's life heck. Such was the case here as über-owner-technician Mac admonishes sidekick Barney for not taking time...

Many Thanks to Berkeley Nucleonics for Continued Support!

Berkeley Nucleonics Corp - RF CafeBerkeley Nucleonics Corporation (BNC) is a leading manufacturer of precision electronic instrumentation for test, measurement, and nuclear research. Founded in 1963, BNC initially developed custom pulse generators. We became known for meeting the most stringent requirements for high precision and stability, and for producing instruments of unsurpassed reliability and performance. We continue to maintain a leadership position as a developer of custom pulse, signal, light, and function generators. Our designs incorporate the latest innovations in software and hardware engineering, surface mount production, and automated testing procedures.

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

/jobs.htm" target="_top"> 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...

New 2-D Material Blocks Electromagnetic Interference

New 2-D Material Blocks Electromagnetic Interference - RF Cafe"Researchers from Drexel University have discovered a two-dimensional material that has the ability to block electromagnetic interference. Drexel University The material comes from a two-dimensional family known as MXenes. These materials were first produced back in 2011 at Drexel University. Since then, researchers have discovered remarkable properties in many of these two-dimensional materials - and this new discovery could prove to be one of the most exciting yet. The material is known as titanium carbonitride. This discovery breaks all the barriers that existed in the electromagnetic shielding field. It not only reveals a shielding material that works better than copper, but it also shows an exciting, new physics emerging, as we see discrete two-dimensional materials interact with electromagnetic radiation in a different way than bulk metals..."

Know Your Levels

Know Your Levels, June 1958 Radio-Electronics - RF CafeThe old adage about a picture being worth a thousand words is still true today, even in the Information Age in which we live. A lot of people, especially those new to the field of electronics, struggle with the concept of decibels as applied to power and voltage (and to a lesser degree current). A plethora of computer, browser, and phone app programs are available to make individual, specific conversions, but what has been learned about the fundamental relationship? A nomograph is still one of the best tools both for teaching and performing conversions. This article that discusses properly matching impedances of amplification stages includes a nice nomograph...

EDN's 2020 Mind of the Engineer Survey

EDN's 2020 Mind of the Engineer Survey - RF CafeEDN has published the results of their 2020 "Mind of the Engineer" survey. It reflects changes in attitudes and workplace preferences in this era of the Wuhan Virus (aka COVID-19). Many engineers - and other workers - are discovering that they really like working remotely from home. Of course some jobs require a physical presence at an office building, but a lot of engineers are setting up labs in their homes where possible. "What's on the design engineer's mind in 2020, the year pundits claim will change the workplace forever with the option to work remotely during the COVID-19 pandemic? The electronic design arena is already starting to witness the change, as corroborated in the latest 'Mind of the Engineer' survey carried out by AspenCore, the parent company of EDN. For instance, while most engineers prefer to conduct circuit design..."

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.

Thursday 20

How Audions Were Built

How Audions Were Built, January 1947 Radio-Craft - RF CafeIf you have never read the story of Lee de Forest's journey from initial experiments to finally achieving success with his amplifying vacuum tube, the Audion, then you might want to take a few minutes to look over this article. It was published in a 1947 issue of Radio-Craft magazine as part of the 40th anniversary of the invention that changed the electronics world. With so many other things which are nowadays very commonplace, we tend to not think about or appreciate the ingenuity and effort that went into them. It is one thing to make incremental improvements in an existing technology, but to conceive of and created an entirely new realm of science is quite another. As with Albert Einstein's relativity and Robert Goddard's liquid-fueled rockets, and the Wright brothers' powered aeroplane...

TotalTemp Intros Wide Range Thermal Platforms

TotalTemp Technologies Intros Wide Range Thermal Platforms - RF CafeTotalTemp Technologies is expanding its offerings to include more products such as custom wide range temperature chambers. Featured here is the model C230 temperature chamber with custom apertures on four sides and +325°C to -160°C temperature range. It features time tested designs and the award winning synergy Nano temperature controller. Meet your custom requirements in a better way than with off the shelf solutions. Two year warranties and accessible knowledgeable support before and after the sale. TotalTemp also offers a new product line of refrigerated custom thermal platforms capable of -70°C without the need for expendable coolants...

U.S. Special Ops Orders Inflatable Satellite Antennas

U.S. Special Ops Orders Inflatable Satellite Antennas - RF Cafe"U.S. Special Operations Command could order up to $172M worth of inflatable satellite communications terminals under a new five-year contract with GATR Technologies, a subsidiary of Cubic Corp. By using an inflatable radome, GATR Technologies' antennas are designed to be ultra-portable and easy to set up. The smaller version can be set up in less than 20 minutes, while the larger can be set up in less than 30 minutes. Consisting of five one-year ordering periods, the indefinite delivery, indefinite quantity contract provides for the procurement of 1.2-meter and 2.4-meter inflatable satellite communications terminals and related equipment. The contract was issued as a Phase III Small Business Innovation Research award by USSOCOM..."

Carl & Jerry: Extracurricular Education

Carl & Jerry: Extracurricular Education, July 1963 Popular Electronics - RF CafeThis "Carl and Jerry" episode entitled "Extracurricular Education" is a bit far-fetched compared to the typical storyline, but it does illustrate how when you are desperate to get out a distress signal, a little technical knowledge and having a knack for improvisation can save the day. Back then there were probably a lot more people sitting around their radios or TVs who might have heard the SOS message and actually know what it was. I am no Morse code master, but anytime I hear the familiar di-di-dit dah-dah-dah di-di-dit (··· --- ···) cadence in a movie or anywhere else, my attention tunes into it like a mother recognizes her baby's cry in a noisy room. Interestingly, seat belts are mentioned in this 1963 issue of Popular Electronics magazine. Ford began installing them in 1955 as an option...

ConductRF High Flex VNA Test Cables for 40, 50 & 70 GHz

ConductRF High Flex VNA Test Cables for 40, 50 & 70 GHz - RF CafeConductRF offers RF Engineers a large selection of Hi Flex cable for vector network analyzers (VNAs). We have standards for applications at 18-40 GHz, 50 GHz & 70 GHz. Our torque resistant connector heads and phase stable constructions ensure great performance for many tests to come. Other key features include: 2.92 mm, 2.4 mm & 1.85 mm connector options, low VSWR & insertion loss, low phase change with flexing, options available swept right angle connectors. ConductRF VNA series provides customers with reliable ruggedized solutions for Lab and Production Vector Network Analyzer testing. With options for 18 GHz, 26.5 GHz, 40 GHz, 50 GHz, & 70 GHz, these cables offer cost leading alternatives to original OEM VNA cable solutions...

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.

RF Cafe Quiz #70: Analog & RF Filter Basics

RF Cafe Quiz #70: Analog & RF Filter BasicsThis Analog & RF Filter Basics Quiz targets those of you who are relative newcomers to the world of radio frequency (RF) electronics, but seasoned vets are welcome to give it a go as well. It addresses frequency response and physical construction. Images were obtained from Anatech Electronics documents entitled "Guideline for Choosing RF and Microwave Products" and "Understanding Filter Types and Their Characteristics." API Technologies' "RF & Microwave Filters," is also referenced...

Modelithics Releases the COMPLETE+3D Library v20.4 for Ansys HFSS

Modelithics® Releases the COMPLETE+3D Library™ v20.4 for Ansys® HFSS™ - RF CafeModelithics, is pleased to announce the release of version 20.4 of the COMPLETE+3D Library for use with Ansys HFSS. The library contains over 325 highly scalable Microwave Global Models™ for capacitor, inductor, and resistor families from many popular vendors, plus a collection of nearly 300 Modelithics' 3D geometry models for inductors, capacitors, filters, packages and connectors. Version 20.4 adds five new part value-, pad-, and substrate scalable models and over seventy new full wave 3D electromagnetic models. New scalable circuit models include a new model for Coilcraft's 0402DC inductor series, Johanson's L-14C and L-14W inductor series, and Vishay's CRCW1206 resistor series. New 3D EM models are available for Mini-Circuits' HFCN-740+, HFCN-880+, and HFCN-2700+ filter series...

Fractal Topological Insulators Are All Edge

Fractal Topological Insulators Are All Edge - RF Cafe"In novel materials known as topological insulators, electricity or light can flow around corners and defects with virtually no losses. All topological insulators produced so far are comprised of an insulating bulk and perfectly conductive edges. Now scientists have found - at least in theory - that fractal topological insulators could possibly be made up only of edges, with no bulk at all. Topology is the branch of mathematics that explores what aspects of shapes can survive deformation. For example, an object shaped like a doughnut can get deformed into the shape of a mug, with the doughnut's hole forming the hole in the cup's handle, but it could not get pushed or pulled into a shape that lacked a hole..."

AppCAD ... As Useful as Ever

AppCAD ... As Useful as Ever - RF Cafe Cool ProductWhile company branding and the user interface have changed over the years since AppCAD first appeared on the Hewlett Packard (HP) website, it is still as handy a desktop tool as ever. The most recent incarnation was provided by Avago Technologies, which bought Broadcom in 2015 and then adopted its name. You can now download a free copy of AppCAD from the Broadcom website. Rather than do an extensive write-up about all the calculation screens in AppCAD, I've posted a sampling of screen shots. Amongst them are a Smith chart s-parameter plotter, a lumped element balun designer, a microstrip calculator, a mixer spurious product calculator, and thermal dissipation calculator...

Anatech Intros Ceramic TCAS and Cavity 5G Filters

Anatech Electronics Intros Ceramic TCAS and Cavity 5G Filters - RF CafeAnatech Electronics offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. The AE4570-5080DB5468 passes the frequency bands of 4390-4750 MHz and 4900-5260 MHz. Insertion loss within the pass bands is less that 1 dB and an isolation between the bands of more than 70 dB. The duplexer can handle powers up to 50 watts and can be fitted with either SMA, N type or a combination of both. The TCAS 1090 MHz is a low profile SMT type Ceramic Band Pass Filter has a 1 dB BW of 10 MHz, passing...

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.

Tuesday 18

Diana Moon Radar

Diana Moon Radar, September 1958 Radio & TV News - RF CafeEarth-Moon-Earth (EME) communications have been used by amateur radio operators for a few decades now, made possible by more capable transmitters and receivers as well as digital encoding which facilitates operation closer to the noise floor. EME is regarded largely as a novelty branch of Ham radio since relatively few people are set up to exploit it. In 1946, the U.S. Army Signal Corps created "Project Diana," named for the Roman moon goddess Diana, as an experimental exercise to bounce radar signals off the Moon and receive the reflected signals. It was the first attempt at radar astronomy and was the first time a terrestrial radio signal was bounced off another celestial body. Once artificial satellites were orbiting in the late 1950's, Hams and other entities were encouraged to detect and track orbits and signal transmission properties - including frequency and power - to aid government engineers and scientists in determining stability (electrical and mechanical), speed, rotation, altitude, path, atmospheric and cosmological noise sources, and other parameters...

CMT Announces Power Calibration Integration with LadyBug Technologies

Copper Mountain Technologies Announces Power Calibration Integration with LadyBug Technologies - RF CafeLadyBug Technologies' line of power sensors is now supported in Copper Mountain Technologies S2VNA software. Starting with S2VNA SW v.20.3.1, LadyBug power sensors LB4xx, LB5xx, and LB59xx can be used for power calibration. LadyBug True RMS Average Power Sensors deliver reliable, accurate, power measurements for CW, Pulse, and modulated signals. These diode-based sensors feature a wide dynamic range and a great VSWR. The optional external triggering input feature can be used without any external components. Recorder and Trigger outputs are also available. LadyBug's patented NoZero NoCal technology makes these sensors ideal for calibration systems, automated test stations and other embedded applications...

Europe's 1st Software-Defined Satellite Completes RF Tests

Europe's 1st Software-Defined Satellite Completes RF Tests - RF Cafe"The first European satellite that is capable of being completely repurposed after launch and developed within an ESA Partnership Project - Quantum - has concluded its radio-frequency tests at a specialized facility in Toulouse (France). Quantum is the first ever software-defined satellite, preparing the way for the next generation of telecommunication satellites that can be reprogrammed in orbit. It offers unprecedented in-orbit reconfigurability in coverage, frequency and power, which allows for complete mission rehauls including changes in orbital position. Engineers involved in the Quantum Partnership Project from manufacturer Airbus, operator Eutelsat and ESA (European Space Agency) have developed new working practices that have enabled them to keep working during the coronavirus pandemic. This ensures that the satellite will be fully ready to launch later in the year..."

Theory and Construction of Attenuators, Line Filters and Matching X-formers

The Theory and Construction of Volume Controls, Line Filters and Matching Transformers, May 1932 Radio-Craft - RF CafeHere is Part 1 of a three-part article on attenuator pad and impedance matching articles that appeared in Radio-Craft magazine. Although the focus is on audio frequencies, the principles apply in general. It is interesting to read about wavelengths expressed in units of miles versus feet and meters like we are used to seeing for radio frequencies. Keep in mind that most of the decibel formulas used here are for voltage and not for power. As a reminder, the decibel representation of a ratio is always 10 * log10 (x). If you have a voltage ratio of V1/V2 = 0.5, then 10 * log10 (0.5) = -3.01 dB. If you have a power ratio of P1/P2 = 0.5, then 10 * log10 (0.5) = -3.01 dB. Does that mean that -3.01 dB of voltage attenuation is the same as 3.01 dB of power attenuation? Confusingly, no...

Exodus Advanced Communications AMP2070C Wideband SSPA

Exodus Advanced Communications AMP2070C Wideband Solid State Amplifier - RF CafeExodus Advanced Communications' model AMP2070C is designed for broadband EMI/RFI, laboratory, communications and EW applications. Class A/AB linear design for all modulations & industry standards. Covers 700 MHz – 6.0 GHz, produces 100 W Minimum, 50 W P1dB, with a minimum 50 dB Gain. Excellent gain flatness, optional monitoring parameters for forward/reflected power, voltage, current and temperature sensing for superb reliability and ruggedness. Integrated in our compact 3U chassis weighing <25 kg. Suitable for CW, pulse and all single channel modulation standards. Built-in protection circuits...

Many Thanks to San Francisco Circuits for Continued Support!

San Francisco CircuitsSF Circuits' specialty is in the complex, advanced technology of PCB fabrication and assembly, producing high quality multi-layered PCBs from elaborate layouts. With them, you receive unparalleled technical expertise at competitive prices as well as the most progressive solutions available. Their customers request PCB production that is outside the capabilities of normal circuit board providers. Please take a moment to visit San Francisco Circuits today. "Printed Circuit Fabrication & Assembly with No Limit on Technology or Quantity."

Monday 17

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...

Simulating a CBS Color Signal

Simulating a CBS Color Signal, September 1951 Radio & Television News - RF CafeFor some reason the "too clever by half" saying (but not in an insulting way) comes to mind when reading this article about color TV from a 1951 issue of Radio & Television News magazine. The color television industry was still searching for an acceptable standard broadcast format when this was written, and the electromechanical contraption was not considered too elaborate considering the original color TV schemes were all a conglomeration of whirling colored wheels, light sources, and photodetectors coupled with accommodating timing and intensity signals. Because there was not agreement on what the final commercial broadcast signal format would look like, there was not a lot of motivation for test equipment makers to invest time and money into providing gear for research and development laboratories. Do you remember the ads for the screen that installed on the front of a TV set to convert black and white (B&W) to color...

TotalTemp Technologies Intros Hot-Only Thermal Platforms

TotalTemp Technologies Intros Hot-Only Thermal Platforms - RF CafeTotalTemp Technologies has added hot-only models to the product line of wide range thermal platforms for solder processes and testing. 300 °C and 400 °C models have great pricing, safety and the same flexibility of hot/cold models. Conductive aluminum surface is superior to radiant heat models in speed and control accuracy. The compact, full-featured HSD14 heat-only thermal platform provides a heated surface area of 14 sq.in. and the HSD14 heat-only thermal platform provides a heated surface area of 144 sq.in. Our Watlow EZ-ZONE PM temperature controller is a programmable thermal platform interface with large, easy to read characters with fail-safe and limit setting capability...

Ultra-High-Speed Terahertz Wireless Chip

Ultra-High-Speed Terahertz Wireless Chip - RF Cafe"To enable data transmission speeds that surpass the 5th Generation (5G) standards for telecommunications, scientists from anyang Technological University, Singapore (NTU Singapore) and Osaka University in Japan have built a new chip using a concept called photonic topological insulators. Published recently in Nature Photonics, the researchers showed that their chip can transmit terahertz (THz) waves resulting in a data rate of 11 Gigabits per second (Gbit/s), which is capable of supporting real-time streaming of 4K high-definition video, and exceeds the hitherto theoretical limit of 10 Gbit/s for 5G wireless communications. THz waves are part of the electromagnetic spectrum, in between infrared light waves and microwaves, and have been touted as the next frontier of high-speed wireless communications..."

Army Studies Radio Wave Curvature

Army Studies Radio Wave Curvature, September 1956 Popular Electronics - RF CafeEarly investigations into RF signal atmospheric "ducting" was reported in this 1956-era article in Popular Electronics. Ducting effects were first noticed during World War II when Nazi broadcasts from occupied Paris were received occasionally in London. Scientists discovered that a small change in the humidity of the air near the surface has the effect of trapping radio waves, a trapping process dubbed "ducting." These waves are conducted as if they were inside of a metallic waveguide. Research by the U.S. Army Signal Corps determined a sudden temperature rise at around 50 to 200 feet above the surface appears to have the strongest effect...

Tunable Constant Q Band-Pass Filter Design Using q and k Values

Tunable Constant Q Band-Pass Filter (Brad Baker) - RF CafeRF Cafe visitor Brad Baker, now retired, sent me this paper entitled, "Tunable Constant Q Band-Pass Filter Design Using q and k Values," which he wrote about work he did waaaaay back in the last century before computer simulation and optimization was available on every desktop. Says Brad, "Attached is a filter design I did in '86. I got a job working for a small land mobile radio company as an RF engineer and my first assignment was to design a tunable band-pass filter that tuned from 29 MHz to 59 MHz. I had been out of school for about two years at this point. I had quite a bit of design experience during my co-op semesters doing some RF and baseband filters, IF / analog / baseband amplifiers but nothing like this. I can tell you I was sweating it a little bit."

Many Thanks for Alliance Test Equipment's Support!

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

Sunday 16

Electrical Engineering Crossword Puzzle for August 16th

Electrical Engineering Crossword Puzzle for August 16, 2020 - RF CafeAugust 16th's custom Electrical Engineering themed crossword puzzle contains only only words (1,000s of them) from my custom-created lexicon related to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, find someone or something in the otherwise excluded list directly related to this puzzle's technology theme, such as Hedy Lamarr or the Bikini Atoll, respectively. The technically inclined cruciverbalists amongst us will appreciate the effort.

Friday 14

Varian Associates Radar Illustrations by C.E.B. Bernard

Varian Associates Radar Illustrations by C.E.B. Bernard - RF CafeFrequent RF Cafe visitor who goes by the moniker "Unknown Engineer" sent me a hyperlink to a PDF file on Amazon's CloudFront* content delivery network (CDN - basically a file server) that contains no fewer than 17 amazing radar and vacuum tube related line drawings published by Varian Associates' TWT Division, Palo Alto Tube Division, Solid State Division, Eastern Tube Division, Western Tube Division, Solid State West Division. These highly detailed and busy drawings were done around 1975 by British illustrator/artist C.E.B. Bernard; a search for his works did not reveal much. The events shown are fictitious, as are the accompanying hand-printed stories. Some of the puns are pretty clever, but are somewhat dated for today's readers. To wit, the name Memamadun Ptolemy, which for the uninitiated is an allusion to the movie "Blues in the Night," where the actual words are "My momma done 'tol me..." (get it?). Another worthy mention is, "Tube V or not Tube V, that is the question," an obvious play on Shakespeare's "To be or not to be, that is the question" line by Prince Hamlet. If you recognize those, you'll find other familiar takeoffs as well...

Tiniest Secrets of ICs Revealed with Imaging Technique

Tiniest Secrets of ICs Revealed with Imaging Technique - RF Cafe"The life-givers of integrated circuits and quantum devices in silicon are small structures made from patches of foreign atoms called dopants. The dopant structures provide charge carriers that flow through the components of the circuit, giving the components their ability to function. These days the dopant structures are only a few atoms across and so need to be made in precise locations within a circuit and have very well-defined electrical properties. At present manufacturers find it hard to tell in a non-destructive way whether they have made their devices according to these strict requirements. A new imaging paradigm promises to change all that. The imaging mode called broadband electric force microscopy..."

Vintage College Engineering Labs

Vintage College Engineering Labs - RF CafeWhen I think back at the engineering labs from my days in school, I wonder how much things have really changed from then until now. It is hard to believe that freshman and sophomore labs are not still consumed with radial lead resistors, inductors, and capacitors, solderless breadboards, and a variety of light bulbs, motors, transformers, relays, and rheostats. By the time you move into the junior year, labs have gotten a bit more intense with microprocessor controls (mine used an 8088 CPU with machine language programming for the serial port), some high voltage apparati[sic], digital logic circuits, and a chance to lay out/fabricate/populate a PCB. On-hand test equipment consists of 2nd or 3rd generation oscilloscopes, signal generators, and power supplies. I did a search for photos of labs from back in the early to mid 1900s to see if much had changed from then until the time I was in college...

Apple Patents mm-Wave 5G Antenna that Radiates Through Display

Apple Patents mm-Wave 5G Antenna that Radiates Through Display - RF CafeOn July 28, 2020, Apple was granted patent number US10727570 entitled "Electronic devices having antennas that radiate through a display." Abstract: "An electronic device may be provided with a display and a phased array antenna that transmits radio-frequency signals at frequencies greater than 10 GHz. The display may include a conductive layer that is used to form pixel circuitry and/or touch sensor electrodes. A filter may be formed from conductive structures within the conductive layer. The conductive structures may include an array of conductive patches separated by slots or may include conductive paths that define an array of slots. The filter may include an additional array of conductive patches stacked under the array of conductive patches to allow the slots to be narrower than would be resolvable to the unaided human eye. The periodicity of the conductive structures and the slots in the filter may be selected to tune...

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!

Thursday 13

Heath Company: Heathkit Advertisement

Heath Company Heathkit, July 1955 Radio & Television News - RF CafeHeathkit's claim to fame was that it was able to offer user-assembled kits of high quality electronic products at a price lower than what equivalent factory assembled equivalents would cost. While that is probably generally the case, it is difficult to gauge what the relative quality really is. Some of the kits were easy to assemble for even people with little experience, but a good portion of them required familiarity with soldering and how electronics were put together. The instructions provided were very thorough, complete with photos and drawings of how each step should look. In fact, according to a 1972 installment of Mac's Service Shop entitled "Philosophy of a Kit Manufacturer," every Heathkit kit instruction booklet goes through a rigorous cycle of writing, testing, and rewriting before being released for production...

Practical Solutions for Measuring Phase Noise

Practical Solutions for Measuring Phase Noise - RF CafeAxiom Test Equipment, an electronic test equipment rental and sales company has published a new blog post entitled "Practical Solutions for Measuring Phase Noise" that examines phase noise, what it is, why too much noise and frequency instability can be a problem in testing, and how to find the right method and equipment for measuring it. Phase noise can often be measured directly using different measurement approaches such as residual and cross-correlation techniques, which are explored more in-depth in the blog. Most importantly, the blog explains what specifications to look for in a spectrum or signal analyzer to ensure the best fit for the job. A few equipment examples are given as guides...

Engineering Students Pick the Top Engineering Employers

Engineering Students Pick the Top Engineering Employers - RF CafeUniversum, a self-proclaimed "global employer branding leader" that conducts research studies on career expectations,' surveyed 52,000 engineering students between October 2019 and April 2020 on their preferred places of employment. They were asked who is your preferred employer upon graduation. Design News created a slideshow of the results showing their top 50 dream employers. Numbero uno is Tesla, a U.S. e-car maker, whose stock just approved a 5:1 split after skyrocketing in value after its related (by ownership) sky rocket (SpaceX - the #2 choice) business recently succeeded in launching and returning two American astronauts to the ISS. #3 was Lockheed Martin. Google only rated #4, Apple #7, Microsoft #8, . Lego - the plastic block people, came in at #31. The USAF was #39. General Dynamics completed the list at #50. If the list had gone to #51, RF Cafe would probably have been there.

Tracking Space Junk in Daylight

Tracking Space Junk in Daylight - RF Cafe"Scientists said they had discovered a way to detect space debris even in daylight hours, potentially helping satellites to avoid the ever-growing cloud of junk orbiting the planet. Defunct rockets, satellites and spacecraft parts continue to orbit Earth after they are discarded. The estimated 500,000 objects circling the globe range in size from a single screw to an entire rocket fuel tank. Travelling at thousands of miles an hour, they pose a huge and rising collision risk to satellites. Using lasers, it is possible to detect the debris from the ground..."

Building Your Own Audio Frequency Choke Coils

Building Your Own Audio Frequency Choke Coils, October 1932 Radio-Craft - RF CafeOne very satisfying aspect of 'rolling your own' audio frequency coils (aka chokes, aka inductors), is how well the simple inductance equations match measured end results. Unless you really manage to mangle the job, if you use the right equation and are reasonably careful to observe wire size, spacing (including insulation), and core diameter, you will be amazed at how close practice matches theory. Although strictly speaking audio frequencies run from a few Hertz up to maybe 15 kHz for people with really good hearing. My experience is that similar success can be had even into the low MHz realm with just a little tuning required. It's not until you get into the realm of self-resonance that everything starts falling apart with basic equations...

Anatech Electronics Intros 2 New Cavity Filters

Anatech Electronics Intros 2 New Cavity Filters - RF CafeAnatech Electronics offers the industry's largest portfolio of high-performance standard and customized RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. The P/N AE1200-1400DB5450 passes DC-1200 MHz and 1400-3000 MHz with a crossover insertion loss of 5 dB at 1300 MHz crossover frequency at 1300 MHz and in band insertion loss of less than 1 dB. The AE2310B11640 passes the LTE band of 2305-2315 MHz with an in-band insertion loss of less than 1 dB. The 2305-2315 MHz bandpass filter exhibit a very sharp transition to the rejection band with a power handling of 20 W...

Many Thanks to Reactel for Their Long-Time Support!

Reactel Filters - RF Cafe

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

Wednesday 12

Electronic Crossword Puzzle

Electronic Crossword Puzzle, September 1958 Radio & TV News - RF CafeThis "Electronic Crossword" appeared in the September 1958 issue of Radio & TV News magazine. Its creator, John Gill, designed specialty theme crossword puzzles for many other editions of Radio & TV News and Electronics World (see the big list at the bottom of the page). He considered this crossword to be a "fooler" because he claims to include many "unusual definitions and a number of obscure words which you will have to work around if your vocabulary of 'exotic words' is rusty." It really doesn't seem so difficult to me, and anyone used to working my custom RF Cafe Crosswords will have no problem with it.

Skyworks High Linearity LNAs for Small Cell, Massive MIMO and Base Stations

Skyworks High Linearity LNAs for Small Cell, Massive MIMO and Base Station Applications - RF CafeTo meet the challenging requirements of cellular LTE and 5G NR infrastructure applications, Skyworks has released the SKY67183-396LF and SKY67189-396LF low noise amplifiers (LNAs). These LNAs feature ultra low-noise figure, exceptional linearity, and operate over a wide range of frequencies. To reduce PCB board space, these devices are housed in an ultra-compact 2 x 2 mm plastic surface mount package. The SKY67183-396LF and SKY67189-396LF are ideal for 2G/3G/4G/5G TDD and FDD infrastructure applications, including small cell, massive MIMO, and macro base stations...

Astra Small Satellite Launcher Test Flight from Alaska

Astra Small Satellite Launcher Test Flight from Alaska - RF Cafe"After completing a countdown dress rehearsal, Astra is gearing up for its first orbital launch attempt this week from Kodiak Island, Alaska, but company officials said it will likely take multiple test flights before the new small satellite launcher successfully reaches orbit. Astra's small satellite delivery vehicle was set for liftoff from the Pacific Spaceport Complex in Alaska during a two-hour window opening at 10 p.m. EDT Sunday, or 6 p.m. local time in Alaska. In social media updates, Astra said it fueled the small satellite launcher with liquid propellants Sunday. But officials said out-of-limits upper level winds and a boat in restricted waters offshore of the launch site..."

Transmission-Line Feed for Short-Wave Antennas

Transmission-Line Feed for Short-Wave Antennas, October 1932 QST - RF CafeWhen someone with the first name of "True" writes an article about transmission line feeds for short-wave antennas, you should probably take note. This very topic has been covered in detail many times since the use of impedance-matched transmission lines have been in use (more than a century), but since there are always people new to the concept, it is good to keep introducing the topic on a regular basis."Transmission-Line Feed for Short-Wave Antennas" appeared in a 1932 issue of QST magazine. Even in this era of prefabricated everything, it still often comes down to winding coils and adjusting cable lengths to get optimal impedance matches between transceivers and antennas.

Vanadium: The Other Green Metal

Vanadium: The Other Green Metal - RF CafeI have extolled the virtues of Aerospace & Defense Technology magazine many times for its variety of extremely interesting articles on a wide range of topics. The August issue has a story on the element Vanadium (atomic number 23) and the critical role it plays as an alloy component of metals. At concentrations of less then 0.1%, vanadium can nearly double the strength of steel and aluminum, as well as increasing resistance to corrosion. It is also used as a catalyst (sometimes a substitution for nickel and platinum), in electronics components, and in ceramics. Use of vanadium is considered "green" because most of it is obtained from byproducts of other industrial processes like ash from coal burning. Vanadium is the earth's 22nd most abundant element and is found everywhere, but as you might suspect China provides 61% of the supply while the U.S. does a mere 3% (Russia makes 14%). Fortunately, part of the Dept. of Interior's 2018 charter was to include vanadium on its list of critical commodities and must act to significantly increase domestic production rather than be dependent on foreign sources. It's long past time.

ConductRF Performance TSA89 Flexible RF Test Cables to 40 GHz

ConductRF Performance TSA89 Flexible RF Test Cables to 40 GHz - RF CafeManufacturing of all our products continues to operate at full capacity as part of the "Essential Business" community. Professional high frequency TSA89 series of RF test cables with performance to 40 GHz. Precision connector choices include; SMA, Type-N, 3.5mm, 2.92mm, & 2.4mm. Key features: High-frequency point to point cable, light weight rugged double-shielded, flexible cable, low loss <0.68 dB/ft @ 40 GHz, low VSWR < 1.35:1 (Typical < 1.25:1), RF leakage >-100 dB to 18 GHz, temperature rated from -55ºC to 125ºC. 100% factory VSWR and insertion loss tested. Cables are in stock and available immediately from Digi-Key. Made in the USA.

Many Thanks to Electro-Photonics for Their Continued Support

Electro-PhotonicsElectro-Photonics is a global supplier of RF & Microwave components. Their products include SMT hybrid and directional couplers, wire bondable passive components, mounting tabs, filters, transmission lines, and very useful test boards for evaluating components (spiral inductors, single-layer capacitors). The Electro-Photonics team can support your small R&D design requirements with RF & Microwave test fixtures and save you valuable design and characterization time. Please take a moment to visit Electro-Photonics' website and see how your project might benefit. 

Tuesday 11

Ward Para-Con Antenna

Ward Para-Con Antenna, September 1951 Radio & Television News - RF CafeThe word prefix "para" can mean "above and beyond" or "resembling" or "abnormal or incorrect." Ward Products probably preferred first two be inferred by potential customers when naming their PARA-CON television antenna, although it actually is a shortening of "parabolic." The "con" part is a shortening of "conical." After reading the text of this full-page advertisement from a 1951 issue of Radio & Television News magazine, I'm inclined to assign the third prefix meaning of "para" to it. Then, add in the "con" part where "con" can take on either the noun form meaning of "disadvantage" or the verb form definition of "to trick or defraud," and you get what this antenna truly represented in terms of achieving superior performance. At best the PARA-CON exhibited the characteristics of a phased pseudo-[bi]conical antenna. The allusion to a parabolic antenna...

Metasurface Optical Chip Expands Use of Quantum Sensors

Metasurface Optical Chip Expands Use of Quantum Sensors - RF Cafe"Sensing devices have a range of industrial uses - from carrying out ground surveys to monitoring volcanoes - and scientists are developing ways to improve their sensitivity with quantum technologies that are based on cold atoms. Machines using quantum technology are, however, bulky and difficult to transport, making current designs unsuitable for most industrial uses. According to Birmingham University, the researchers have used a new approach that will enable quantum sensors to shrink to a fraction of their current size. The research was conducted by an international team led by Birmingham University and SUSTech in China in collaboration with Paderborn University in Germany. Their results are published in Science Advances..."

Student's Radio Physics Course - Series & Parallel Circuits

Student's Radio Physics Course, Series + Parallel Circuits, July 1932 Radio News - RF CafeNot everyone who visits websites like RF Cafe is a seasoned electronics veteran. While I and most likely you, too, can do series and parallel circuit analysis (and series/parallel for that matter, possibly using Fourier or La Place transforms for reactive AC circuits) in our sleep, many are recently getting into the wonderful world of electronics who are just coming of age or have suddenly at a later point in life developed a passion for the craft. Accordingly, this article from Radio News magazine provides yet another tutorial on the fundamentals of series and parallel circuit analysis. Only resistors and basic Ohms law are covered...

Withwave Intros 1.0 mm to 1.0 mm Adapter Series

Withwave Intros 1.0 mm to 1.0 mm Adapter Series (DC to 110 GHz) - RF CafeWithwave's Precision 1.0 mm to 1.0 mm Adapter Series are designed based on precision microwave interconnection technologies. Configurations include 1.0 mm (F) to 1.0 mm (F), 1.0 mm (M) to 1.0 mm (F), and 1.0 mm (M) to 1.0 mm (M). These Adapters are manufactured to precise microwave specifications and constructed with male and female gender on both side. The precision microwave connector interfaces ensure an excellent microwave performance up to 110 GHz. Features: Frequency range = DC to 110 GHz, VSWR (max) = 1.30:1, Body = stainless steel (passivated)...

Many Thanks to Aegis Power Systems for Their Continued Support!

Aegis Power Systems - RF CafeAegis Power Systems is a leading supplier of AC-DC and DC-DC power supplies for custom and special applications. Aegis has been designing and building highly reliable custom power supplies since 1995. They offer a complete line of switch mode power supplies and power converters for a variety of markets including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft, EV, telecom, and embedded computing applications. Design and manufacture of custom power supply solutions to meet each customer's exacting specifications. Please visit Aegis Power Systems today.

Monday 10

Comics with an Electronics Theme

Comics with an Electronics Theme, February 1967 Popular Electronics - RF CafeHere are a couple more tech-themed comics from a vintage electronics magazine (Popular Electronics). The one from page 101 reminds me again about how different the world of retail sales is today compared to just two short decades ago. Prior to the advent of online marketing and sales, you either walked into a brick and mortar (a term rarely heard before the Internet era) type store and walked out with your purchased product, or you thumbed through a catalog and placed an order either by mail or telephone. Most people opted to pay for a postage stamp rather than pay the long distance phone charge (a term rarely heard today). Free overnight or 2-day shipping from many e-stores makes online shopping nearly as instantaneous as walking into a store. People under 20 years old have never known much different, but some old-timers still find the paradigm change strange. The way things are going...

Exodus Advanced Communications Intros X-Band High Power Pulse Amplifier

Exodus Advanced Communications Intros X-Band High Power Pulse Amplifier - RF CafeExodus Advanced Communications' model Exodus AMP5055P-SSC Pulse Amp (9.6-9.9 GHz, 150 W pulse) is IP67 rated and fully qualified for outdoor applications. Designed for Pulse/Radars in the harshest of environmental conditions up to a 20% duty cycle. The unit provides outstanding Pulse fidelity, excellent band flatness, all in a compact lightweight package with the highest reliability. Other frequency ranges & power levels available. Features: Outdoor waterproof packaged high power SSPA, class AB Pulse, GaN design, designed for high power X-band pulse applications, built-in control, monitoring, and protection circuits, high reliability and ruggedness...

The Ham Who Was President

The Ham Who Was President, November 1952 QST - RF CafeSince this is a presidential election year, I figured it would be a good time to post a tongue-in-cheek- story that appeared in the November 1952 issue of QST magazine about a fictional American president J. Willoughby Winkelspoof. The ARRL always has been and still is apolitical, so don't take seriously anything you read here. If you are an astute follower of politics, you might pick up on the nuances woven into the story, and might even marvel on how much the political landscape has changed in the half century since Pres. Winkelspoof graced the Oval Office. Incidentally, the 1952 presidential election was between Dwight D. Eisenhower and Adlai Stevenson. You might wonder how many U.S. presidents were/are Amateur Radio operators. Answer...

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.

Vintage Tech at Insanely High Prices

Vintage Tech at Insanely High Prices - RF CafeFrequent visitor and contributor Joe B. sent me a link to a page entitled, "40 Hilarious Ads For Technology From The Past That Look Insanely Expensive Now." It fits in well with the theme of RF Cafe so you might enjoy being reminded of (if you're old like me) or seeing for the first time (if you're not old like me) what people were paying for technology which was bleeding edge then and is toy-quality now. No kidding. Pick any microprocessor-driven toy from a shelf at Walmart and it will have nearly as much memory and processing power. One example is a 10 MByte hard drive costing $3,398 in 1981, which is the equivalent of $10,069 ($1k/MByte) in 2020 money per the BLS Inflation Calculator. These kinds of themes can be found all over the Internet, and as usual, the same set of examples are repeated on those pages. Do an image search on "10 mbyte hard drive ad" and you'll see what I mean.

Teledyne Aerospace & Defense Electronics UK Launches New Business Unit

Teledyne Aerospace & Defense Electronics UK Launches New Business Unit: Teledyne Energetics UK - RF CafeTeledyne Aerospace & Defense Electronics UK (TADE UK) announced the latest business unit addition to its brand portfolio, Teledyne Energetics UK, headquartered in Lincoln, England. Visit the home page of the company's new website here. The new website gives an overview of the Energetics UK systems, subsystems, and component offerings, which are ITAR-free and designed and manufactured exclusively in the UK. The website promotes the company's extensive heritage in all major deployment theatres including aerospace, land, surface maritime, subsea ASW and LEO launch. Teledyne Energetics UK designs and develops solutions for the safety, arming, and initiation technology sector, in particular military energetic devices...

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

NorthEast RF - RF CafeNorthEast RF's comprehensive antenna testing services include linear | circular polarized antenna measurements and OTA cellular device pre-compliance. Up to 18" diameter and <10 kg weight. Antennas can be rapidly evaluated and optimized using our fast near field spherical system. Test results supplied in data file with pattern viewer software. A picture of the test configuration is included to help aligned axis. Our selection of human head and hand phantoms are ideal for verification of body worn devices. Turnaround time is usually 3-days.

Sunday 9

Amateur Radio Crossword Puzzle for August 9th

Amateur Radio Crossword Puzzle for August 9, 2020 - RF CafeAugust 9th's custom Amateur Radio crossword puzzle contains many words particular to Amateur Radio (labeled with an asterisk *). Each week for two decades I have created a new technology-themed crossword puzzle using only words (1,000s of them) from my custom-created lexicon related to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, find someone or something in the otherwise excluded list directly related to this puzzle's technology theme, such as Hedy Lamarr or the Bikini Atoll, respectively. Avid cruciverbalists amongst us...

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KR Electronics (RF Filters) - RF Cafe

Axiom Test Equipment - RF Cafe

Innovative Power Products Passive RF Products - RF Cafe