Homepage Archive - July 2019 (page 4)

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page. About RF Cafe.

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Friday 26

Cause for Alarm: Slump in Jobs in Electronics

Cause for Alarm: Slump in Jobs in Electronics, May 18, 1964 Electronics Magazine - RF CafeNationwide survey shows a decline in opportunities for engineers. Although jobs are fewer and requirements tougher, certain specialists are still in demand. An employment-agency official on Long Island says, "If it weren't for Grumman (Aircraft Corp.), you could just cut Long Island off and let it float into the Atlantic." A Chicago agency that specializes in jobs for engineers advises applicants to relocate and be prepared to drop out of the five-figure salary range. These are typical findings in a coast-to-coast employment survey. Don't panic; these statements are from a 1964 issue of Electronics magazine. Prior to our current Era of Wireless, which, unbeknownst to most people, is a nomenclature that harkens back to a century earlier ...

RF Stencils for Visio v3.1 Available!

RF Microwave Wireless Analog Block Diagrams Stencils Shapes for Visio - v3 - RF CafeWith more than 780 custom-built symbols, 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 from scratch to fit proportionally on the provided A- and B-size drawing page templates (you can use your own page if preferred). Components are provided for equipment racks (EIA and ETSI) and test equipment, system block diagrams and conceptual drawings, and for schematics ...

Job Opening: EMI Development & Manufacturing Engineer Wanted by Eeonyx

/2019/Eeonyx-EMI-Development-Manufacturing-Engineer-7-25-2019.htm" target="_top" EMI Development & Manufacturing Engineer Wanted by Eeonyx - RF CafeHere is a very unique opportunity for an RFI/EMI engineer. Eeonyx is a leading research development and manufacturing company of electrically conducting materials including piezoresistive sensing textile, resistive heating textile, ESD textile, ESD fibers, EMI shielding textile and felt, capacitive sensing textile, electrically conductive additives, and conductive inks. The Company's partners include industry leaders in the aerospace, apparel, defense, smart fabric pressure sensors, medical device and electronics. Eeonyx is seeking a creative /2019/Eeonyx-EMI-Development-Manufacturing-Engineer-7-25-2019.htm" target="_top" EMI shielding material development and manufacturing engineer. The engineer will plan and conduct development of new electromagnetic materials technology towards commercial applications ...

De Forest Radio Company Advertisement, 1931 QST

De Forest Radio Company Advertisement, December 1931 QST - RF CafeLee de Forest, inventor of the Audion vacuum tube, created a business called De Forest Radio Company (although I hear he didn't build that). This advertisement for his company's electron tubes appeared in the December 1931 edition of the ARRL's QST magazine. If you research Lee de Forest, you will find his name spelled incorrectly in many different forms: de Forest, De Forest, de Forest, de Forest, to give a few. When in doubt, go straight to the source, which in this case is the signature that de Forest placed on his patent applications - he used "de Forest." Note that the official company name, according to the advertisement address at the bottom, is "De Forest Radio Company," (space used) yet the text of the copy uses the form ...

Keysight Technologies Engineering Rulers - Free

Keysight Technologies Engineering Rulers - RF CafeKeysight Technologies is offering these two Engineering Rulers for free for a limited time. One is a digital electronics ruler and the other is a microwave substrate ruler. No detailed information is available at this time. I searched fairly extensively for details but could not find anything at all. It appears that you will have to order one or both for yourself to discover exactly what they are. I gave Keysight my contact information - which they have had for a long time anyway - in exchange for having them sent to me. High resolution images will be posted when/if they arrive. Stay tuned... or get your own ...

Is Ham Radio a Hobby, a Utility...or Both? Spectrum Battle Heats Up

Is Ham Radio a Hobby, a Utility...or Both? Spectrum Battle Heats Up - RF Cafe"Like many amateur radio fans his age, Ron Kolarik, 71, still recalls the 'pure magic' of his first ham experience nearly 60 years ago. Lately, though, encrypted messages have begun to infiltrate the amateur bands in ways that he says are antithetical to the spirit of this beloved hobby. So Kolarik filed a petition, RM-11831 [PDF], to the U.S. FCC proposing a rule change to 'Reduce Interference and Add Transparency to Digital Data Communications.' And as the proposal makes its way through the FCC's process, it has stirred up heated debate that goes straight to the heart of what ham radio is, and ought to be. The core questions: Should amateur radio - and its precious spectrum - be protected purely as a hobby, or is it a utility that delivers data traffic ..."

Nova Microwave: RF & Microwave Circulators & Isolators

Nova Microwave circulators & isolatorsNova Microwave is a leader in technically differentiated electronic and radio frequency Ferrite Circulators and Isolators that connect, protect and control critical commercial and military wireless telecommunications systems. Our staff is dedicated to research and development of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz to 26.5 GHz. Available in single or multi-junction topographies, the Nova Microwave product line of is specifically designed for use in varied environmental and temperature extremes.

Thursday 25

Mac's Radio Service Shop: Satisfied Customer Insurance

Mac's Radio Service Shop: Satisfied Customer Insurance, May 1952 Radio & Television News - RF CafeAs always, the reading of this Mac's Radio Service Shop techno-saga leaves you a little bit smarter about an aspect of electronics as well as how to approach business from both the serviceman's and the customer's perspective, with a bit of humor and personality thrown in for good measure. Author John T. Frye, who also wrote the long-running and much-loved Carl & Jerry series, uses service shop proprietor "Mac" McGregor as a sort of alter ego for passing on his own extensive knowledge of radio and television servicing. Customer satisfaction is the main theme of this installment, which entails going beyond just repairing the problem the items is brought in for. Mac instructs his young wingman technician Barney to run a series of standard tests on every set in hopes of ferreting out ...

Windfreak Technologies Intros SynthHD PRO (v2)

Windfreak-Technologies-SynthHD PRO (v2) - RF CafeWindfreak Technologies, LLC, announces the availability of the new SynthHD PRO Dual Channel RF Signal Generator. The SynthHD PRO is designed for higher amplitude accuracy and operation in a more rugged environment than its earlier sibling, the SynthHD. The entire first manufacturing run has already been shipped. These devices have set the bar on microwave radio frequency generators for quality, size and price. As always, our products are designed and manufactured in the USA! Tune any frequency between 10 MHz and 24 GHz in 0.1 Hz resolution. Adjust calibrated amplitude in 0.1 dB resolution up to +20 dBm and across more than 55 dB of range. Each channels has independent frequency ...

Diode Switch Circuit Quiz

Diode Circuit Quiz, July 1961 Popular Electronics - RF CafeTest your diode switch analysis skills here with six circuits designed by Mr. Robert P. Balin in the July 1961 issue of Popular Electronics. When evaluating the equivalent circuits with the diodes biased on or off, don't make the job more difficult for yourself by considering whether there is enough voltage or current to turn a particular diode on or not, just whether the diode is forward or reverse biased. Doing so reduces everything to simple series and parallel combinations. Redrawing each circuit either with a short for a forward biased diode and an open for a reverse biased diode makes the task easier ...

Notable Quote by "The Father of GPS"

Notable Quote by "The Father of GPS" - RF Cafe"Reliance on satellite navigation and timing systems has become a single point of failure for much of America and is our largest, unaddressed critical infrastructure problem." - Dr. Brad Parkinson, aka "The Father of GPS." According to the Wikipedia entry, "Bradford Parkinson is an American engineer and inventor, retired United States Air Force colonel and recalled emeritus professor at Stanford University. He is best known as the lead architect, advocate and developer, with early contributions from Ivan Getting and Roger Easton, of the Air Force NAVSTAR program, better known as Global Positioning System (GPS)."

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. 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 ... 

Linx Intros Single-Band Monopole Whip Antennas for Cellular IoT and LPWA Applications

Linx Technologies Intros Single-Band Monopole Whip Antennas for Cellular IoT and LPWA Applications - RF CafeLinx Technologies, a Merlin, OR based developer and manufacturer of antennas, is pleased to introduce their line of Single-Band Monopole Whip Antennas for cellular IoT and LPWA applications. When rugged simplicity coupled with targeted performance is required, CW Series and PW Series antennas are a great solution. Linx single-band monopole antennas provide better performance in the targeted frequency band than do most multiband antennas while typically costing less. CW Series antennas mount with an SMA or reverse polarity SMA connector while the PW Series antenna are cabled panel-mount solutions with either a U.FL/MHF connector or plain wire ...

Simulation Game Makes Graphene Research Available to Public

Simulation Game Makes Graphene Research Available to Public - RF Cafe"The team of Toma Susi at the University of Vienna uses a state-of-the-art electron microscope, the UltraSTEM, to manipulate strongly bound materials with atomic precision. Since the instruments are fully computerized, it is possible to show in a simulation how researchers actually use them. This allows for compelling and largely realistic presentations of the most recent research in materials science. A simulation game on display at the Vienna Technical Museum in a special exhibition is now available online, together with the latest research advance of silicon impurity manipulation ..."

PCB Directory: Printed Circuit Board Fabrication & Assembly

PCB  Directory - RF Cafe

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 (e.g., material, flexible, rigid), Geographical location, and more.

Wednesday 24

Commercial Aspects of Single-Sideband

Commercial Aspects of Single-Sideband, May 1956 Radio & Television News - RF CafeAfter discussing the technical benefits of single-sideband (SSB) amplitude modulated (AM) commercial transmission versus double-sideband + carrier standard AM, author Jack Brown concludes with a chart plotting the relative cost of each method versus output power. The result: Transmitters with less than 100 watts output the initial equipment cost of a single-sideband transmitter is greater than its standard AM counterpart. My guess is that with today's equipment the chart would look a lot different, and there may be no dollar cost benefit either way from a hardware perspective. The benefit of SSB of course is in spectrum efficiency and, especially for very high powers, operational cost savings on electricity bills. Even so, commercial AM broadcast radio stations in the U.S. still transmit using ...

Keysight Whitepaper: The Essential Signal Generator

Keysight Technologies Whitepaper: Eliminate Uncertainties and Doubts from Your Test Results - RF CafeKeysight Technologies, Inc. (NYSE: KEYS), a leading technology company that helps enterprises, service providers and governments accelerate innovation to connect and secure the world, has published a whitepaper entitled "The Essential Signal Generator Guide Building a Solid Foundation in RF - Part 1." With all the functions now integrated into wireless devices, verification and production tests are taking up more and more of your time. But the race to get to market hasn't slowed down a bit. Enter, the reliable signal generator. A signal generator with the right capabilities, like fast switching, can help you improve test throughput and reduce cost ...

CMT Seeking a Technical Sales Territory Manager

/2019/copper-mountain-technologies-job-sales-manager-7-24-2019.htm" target="_top" Copper Mountain Technologies Needs a Technical Sales Territory Manager - RF CafeCopper Mountain Technologies' /2019/copper-mountain-technologies-job-sales-manager-7-24-2019.htm" target="_top" Technical Sales Territory Manager will be a part of our growing global sales team. Our USB VNAs are next generation analyzers designed to meet the needs of 21st Century engineers. Our VNAs include an RF measurement module and a processing module, a software application which runs on a Windows PC, laptop or tablet, connecting to the measurement hardware via USB interface. CMT was awarded innovation and product leadership awards by Frost & Sullivan in 2015 and 2017. The successful candidate will have the technical background, sales experience, and personal drive to solve customers' technical and business problems ...

Why Your Son Should Learn Radio - A Talk with "Dad"

Why Your Son Should Learn Radio - A Talk with "Dad", April 1935 Short Wave Craft - RF CafeFrom keeping your son off the streets and out of pool rooms to learning the use of his hands and mind for designing, building, and operating radio, John T. Frye, later of "Carl & Jerry" authorship fame in Popular Electronics magazine, offers no less than eight good reasons why a man should encourage his son (and/or daughter) to take up amateur radio as a hobby - preferably one that will last a lifetime. As is true with any activity that requires a person to exercise hand-eye coordination and think logically about the order and method for best accomplishing a task, Ham radio offers the complete gambit of life skills that should be nurtured at an early age. In the same manner a musician benefits mightily from learning to read and play music while the brain is still in the process of wiring ...

On-Demand Control of THz & Infrared Waves

On-Demand Control of THz & Infrared Waves - RF Cafe"The ability to control infrared and terahertz waves using magnetic or electric fields is one of the great challenges in physics that could revolutionize optoelectronics, telecommunications and medical diagnostics. A theory from 2006 predicts that it should be possible to use graphene - a monoatomic layer of carbon atoms - in a magnetic field not only to absorb terahertz and infrared light on demand but also to control the direction of circular polarization. Researchers from the University of Geneva, Switzerland, and the University of Manchester have succeeded in testing this theory ..."

Empower RF Systems: RF & Microwave Power Amplifiers

Empower RF SystemsEmpower RF Systems is a global leader in power amplifier solutions. Empower RF Systems is an established and technologically superior supplier of high power solid state RF & microwave amplifiers. Our offerings include modules, intelligent rack-mount amplifiers, and multi-function RF Power Amplifier solutions to 6 GHz in broadband and band specific designs. Output power combinations range from tens of watts to multi-kilowatts. Unprecedented size, weight and power reduction of our amplifiers is superior to anything in the market at similar frequencies and power levels.

Tuesday 23

The Quest for the Crystal That Amplifies

The Quest for the Crystal That Amplifies, June 1968 Popular Electronics - RF CafeHmmmm... I never really thought about the transistor as a crystal amplifier (a la the 'crystal detector'), but in fact it was fabricated from a crystal of germanium with two 'cat whisker' wires pressing on its surface. Before the transistor was the simple rectifier made of a crystal of selenium or even carborundum with a point contact. Those were used for turning AC into DC and for detecting radio wave modulation envelopes. For a really good synopsis of the early development path of semiconductors, read this story from a 1968 edition of Popular Electronics that commemorated the 20th anniversary of Bardeen, Shockley, and Brattain announcing their transistor. Having been written much closer to the days of discovery, the story has not been filtered ...

Altum RF Announces RF Test Lab in Eindhoven, Netherlands

Altum RF Announces RF Test Lab in Eindhoven, Netherlands - RF CafeAltum RF, a supplier of high-performance millimeter-wave to digital semiconductor solutions for next generation markets and applications, announces the expansion of its Eindhoven, Netherlands office with an RF Test Lab. Altum RF's Eindhoven office is located on the campus of Eindhoven University of Technology and now includes full RF test and characterization infrastructure up to 40 GHz. The RF lab also ensures ESD-safe measurements. "Expanding our Eindhoven office with full RF measurement capabilities demonstrates our commitment to growing our European customer base," stated Greg Baker, Altum RF CEO. "This investment also highlights our dedication to research and development to ensure our products ...

An Old Spark Soliloquizes

An Old Spark Soliloquizes, December 1931 QST - RF CafeIf it has been a while since you read a story with terms and phrases like "splinters of galena," "the day of the tuning coil that stretched from the front bedroom to the back library; or from the attic to the cellar," and "Ether God," then this article from the December 1931 edition of QST is for you. Galena, by the way, is a semiconductor with a bandgap of about 0.4 eV that was used as the crystal in crystal radio sets. It was used as a point-contact diode along with a safety pin or similar sharp wire, commonly known as a "cat's whisker." In fact, the very first transistor developed by Drs. Bardeen, Shockley, and Brattain used two cat's whisker type contacts on their crystals of germanium ...

Electro-Photonics Intros 16-17 GHz SMT Hybrid Coupler

Electro-Photonics Intros 16-17 GHZ SMT Hybrid Coupler - RF CafeElectro-Photonics LLC, a market leader in RF and Microwave components, has released a new high frequency surface mount (SMT) hybrid coupler: Q3HF-16500. The Q3HF-16500, 90° hybrid coupler operates from 16-17 GHz, dissipates 50 W, and offers excellent coupling flatness and isolation for the most critical applications. This coupler has a very small size of 0.175 x 0.175 inches (4.44 mm x 4.44 mm). The Q3HF-16500 is a RoHS compliant product. The couplers have SMT launches that are fully optimized for the recommended board layout. Our 3 dB 90° hybrid couplers have low insertion loss and high power capability in a small package ...

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

/rfcafejobs.htm" target="_top" Engineering Job Board - R 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 /jobs.htm" target="_top" job openings. HR department employees and/or managers of hiring companies are welcome to submit opportunities for posting at no charge (of course a gratuity will be graciously accepted). 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 ...

Thin Film Converts Heat from Electronics into Energy

Thin Film Converts Heat from Electronics into Energy - RF Cafe"Nearly 70% of the energy produced in the U.S. each year is wasted as heat. Much of that heat is less than 100°C and emanates from things like computers, cars or large industrial processes. Engineers at the University of California, Berkeley, have developed a thin-film system that can be applied to sources of waste heat like these to produce energy at levels unprecedented for this kind of technology. The thin-film system uses a process called pyroelectric energy conversion, which the engineers' new study demonstrates is well suited for tapping into waste-heat energy supplies below ..."

Anatech Electronics: Off-the-Shelf and Custom RF & Microwave Filters

Anatech Electronics logo - RF CafeAnatech Electronics (AEI) manufactures and supplies RF and microwave filters for military and commercial communication systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard RF filter and cable assembly products are published in our website database for ease of procurement. Custom RF filters designs are used when a standard cannot be found, or the requirements dictate a custom approach. Sam Benzacar's monthly newsletters address contemporary wireless subjects. Please visit Anatech today to see how they can help your project succeed. 

Monday 22

Silent Sound

Silent Sound, June 1955 Popular Electronics - RF CafeThis article from a 1955 issue of Popular Electronics discusses the state of the art of ultrasonic transducers and equipment that uses them. Amazingly, of all the applications that are mentioned, one is glaringly missing. Author Louis Garner, Jr., mentions using ultrasonic transducers for measuring material thickness, detecting flaws on and within materials and assemblies, cleaning by ultrasonic scrubbing, soldering*, and motion detection for security systems. The missing items of course is sonar (sound navigation and ranging). The U.S. Navy was using sonar during World War II, although it had been in development a couple decade earlier - similar to radar's evolution. 15 - 20 kc (kHz) frequencies were typical in the day. Modern ultrasonic cleaners use up to 40 kHz, and high resolution sonars run into the low MHz. Oh, also missing is ultrasound imaging like what is used for prenatal and other internal ...

CMT Announces Strategic Relationship with NI

Copper Mountain Technologies Announces Strategic Relationship with National Instruments - RF CafeCopper Mountain Technologies is pleased to announce their strategic relationship with National Instruments. This exclusive collaboration will bring world-class VNA performance and speed to National Instruments' PXI solution. National Instruments is set to release the Copper Mountain Technologies PXIe-S5090 9 GHz 2-Port VNA in August of 2019. National Instruments will be the exclusive channel for purchasing Copper Mountain Technologies' PXI compatible VNAs. This solution brings National Instruments' users access to a metrology-grade VNA and allows Copper Mountain Technologies to expand the solutions it provides for manufacturing and production ...

R & S Test & Measurement Newsletter - July 2019

Rohde & Schwarz Test & Measurement Newsletter - July 2019 - RF CafeWe've gathered our latest content and opportunities to connect for you. We hope you'll enjoy the information and join us at a face-to-face event soon! Topics in this month's Test & Measurement Newsletter include: Comparison of Time Domain & Stepped Frequency Scans in EMI Test Receivers, Phase Noise of Clock and LO Components in 5G Base Stations, The Importance of Accurate S-Parameters for PAM-4 Applications. and Product Highlight: R&S FSVA3000 Signal and Spectrum Analyzer ...

Field-Effect Transistor Circuits

Field-Effect Transistor Circuits, May 1967 Electronics World - RF CafeIf you are just entering the field of electronics, the concepts presented in this half-century-old article for basic field effect transistors are still relevant. Significant improvements have been made since then, but the fundamentals stand. One of the most useful items in this article is Table 1, which compares and contrasts vacuum tubes, bipolar junction transistors, and field effect transistors. Topics covered include general properties of FETs, source followers (a la emitter followers in BJTs), common source amplifiers (a la common emitter amplifiers in BJTs), the Miller oscillator, combinations of FETs and BJTs, and a gated amplitude modulator ...

USAF Microwave Weapon Named "Thor" Can Kill Drones

USAF Microwave Weapon Named "Thor" Can Kill Drones - RF Cafe"Scientists from the Air Force Research Laboratory at Kirtland Air Force Base have created a new type of microwave weapon that can take down drones. Using an inaudible and invisible magnetic wave, the high-powered device could prove a powerful weapon against drones and other unmanned devices. Known as the Tactical High Power Microwave Operational Responder - or THOR for short - the device cost around $15M to make and is capable of taking out multiple drones at a time. THOR was created over a period of 18 months as the need to protect the American military from drones has rapidly increased over time ..."

Res-Net Microwave: Precision RF & Microwave Components

Res-Net Microwave componentsRes-Net Microwave has a complete line of precision RF & microwave components including attenuators, terminations, resistors, and diode detectors for commercial, military, and space applications. Products range from the small flange type to large 2,000 watt connectorized power attenuators and/or terminations at frequencies up to 26.5 GHz. In-house photo etch and laser trim capability. Please check out Res-Net Microwave's website to see how they can help with your current project.

Sunday 21

Engineering & Science Crossword Puzzle for July 21

Engineering & Science Crossword Puzzle July 21, 2019 - RF CafeUnlike all of the other engineering and science-themed crossword puzzles I have ever seen, every word and clue - without exception - in these RF Cafe puzzles has been personally entered into a very large database of relevant terms. The list has been built over nearly two decades of creating these crossword puzzles. Let me know if you would like a custom crossword puzzle built for your company, school, club, etc. (no charge). These custom-made engineering and science-themed crossword puzzles are done weekly for the brain-exercising benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. The jury is out on whether or not this type of mental challenge helps keep your gray matter from atrophying in old age, but it certainly helps maintain your vocabulary and cognitive skills at all ages. A database of thousands of words has been built up ...