Homepage Archive - July 2019 (page 5)

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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See Page 1 | 2 | 3 | 4 | 5 of the July 2019 homepage archives.
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Friday 2

Multicolor Radar

Multicolor Radar, June 1955 Popular Electronics - RF CafeWhat's the big deal about multicolor radar, you might ask? Not much today, but in 1955 color displays were in their infancy. The earliest color cathode ray tubes (CRTs), developed by John Logie Baird in the early 1940s, used just two phosphor colors (magenta and cyan), illuminated by two separate electron guns, to produce a limited color display. Ernest Lawrence came along later in the decade with his tri-color Chromatron CRT, which had separate red, blue and green phosphor dots deposited in a triangular pattern across the inner face of the tube. That is the scheme employed in this first multicolor radar system. It was a major improvement for air traffic controllers since it facilitated ...

Find the Brightest Bulb Quiz

Find the Brightest Bulb Quiz, April 1960 Popular Electronics - RF CafeHere is a nifty little exercise that appeared in the April 1960 edition of Popular Electronics. It has 10 different light bulb circuits and challenges you to figure out which bulb would burn the brightest. All are intuitively obvious to most of us who have been in the field for decades, but do you remember how to do a circuit mesh analysis to prove your "gut?" One way to help figure out what is going on is to re-draw the circuit to eliminate crossing lines, if possible, as in circuit numbers 2, 4, 6, and 10. Also try drawing electrically common nodes as a single connection point, as in circuit #2 where the two nodes in the upper left and right corners are actually the same point. Finally, try to re-arrange the circuit branches into obvious parallel and series paths to make clear any interdependencies ...

Stacked Yagi TV Antennas by Dave Jones, N1UAV

Stacked Yagi TV Antennas (Dave Jones, N1UAV) - RF CafeEvery once in a while an RF Cafe visitor writes to let me know that he or she found one of the vintage electronics magazine articles I post regularly useful. It helps to validate my efforts, which is critical for motivation to continue. A couple days ago Mr. Dave Jones (N1UAV), sent me a note about the stacked television antenna project he undertook after finding the "How to Stack TV Antennas to Increase Signal Strength and to Reduce Ghosts" article from the November 1965 issue of Popular Electronics magazine. His location about 90 miles outside of Nashville, TN, is a challenge for trying to receive a good signal from a television station from both an attenuation and multipath signal degradation perspective. Dave began with a single antenna, but was not happy with the performance. The results of adding the second antenna is amazing ...

Growing Need for Pre-Compliance EMC Testing

Growing Need for Pre-Compliance Electromagnetic Compatibility Testing - RF Cafe"There are a number of electronics-based products available on the market. From the tools found in smart homes to devices designed for the Internet of Things (IoT) to technologies designed to digitalize, there's an enormous density of products that require electromagnetic compatibility (EMC) testing, as well as comprehensive and accurate testing services. In fact, according to a recent research report by Frost & Sullivan, it's being recognized as a prominent market in its own right. Companies need to test their products for unintentional electromagnetic interference (EMI) - and this need has transformed into big business. The market ..."

Electro-Photonics Offering RF & Microwave Products

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.

Thursday 1

Electronics and the IGY - Part I

Electronics and the IGY - Part I, February 1958 Radio Electronics - RF CafeThe International Geophysical Year (IGY) began on July 1 of 1957 and ran through December 31 of 1958. It was the dawn of space / high altitude flight and there was a great need to learn as much as possible about the physics of the upper atmosphere and the void of space. The USSR successfully flew their first three Sputnik satellites and the U.S. was scrambling to get Echo into orbit (finally on August 12, 1960, after the end of IGY). The Cold War was at its peak (Bay of Pigs incident was just a few years away), and the science world was looking for a way to provide a unifying tie between the planet's countries. "During this time, more than 5,000 scientists and engineers of more than 60 nations ...

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. Since according to a popular saying a picture reportedly paints a thousand words ...

ConductRF Phase & Temperature Stable Cables

ConductRF Phase & Temperature Stable Cables February 2019 - RF CafeConductRF is the brand name for Electronic Assemblies Manufacturing, Inc.'s, complete range of RF interconnect products. ConductRF products include solutions for both commercial and precision RF applications for both RF cable assemblies and connectors. Our manufacturing capabilities include solutions built at our ITAR registered facility in Methuen as well as partner facilities in the U.S. and around the world. ConductRF offers cost effective equivalent and improved RF solutions to all major interconnect manufacturers, specializing in phase stability over temperature ...

Sally, the Service Maid: The Case of the Dual Volume Control

Sally, the Service Maid: The Case of the Dual Volume Control, August 1944, Radio-Craft - RF CafeBy 1944, the U.S. and its Allied partners were occupied full-time beating back the forces of Communism, Fascism, Socialism, and many other 'isms.' A vast majority of active service members were men who were either training on domestic soil or fighting on foreign soil. That left sisters, mothers, and grandmothers to conduct a lot of the business and work production jobs that historically had been the near sole purview of men. Rosie the Riveter was a very familiar symbol of that new paradigm, while less known and celebrated were the women who handled building and servicing electronics products. I have posted many articles that appeared in magazines ...

Withwave: RF & Microwave Components

Withwave RF & Microwave Components - RF CafeWithwave manufactures an extensive line of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch, board edge, panel mount), calibration kits (SOLT), a fully automated vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, torque wrenches, test probes & probe positioner. Frequency ranges from DC through 20 GHz. Please contact Withwave today to see how they can help your project succeed.

Wednesday 31

The Muzak Story

The Muzak Story, June 1955 Popular Electronics - RF CafeMost people probably associate "elevator music" with the Muzak format. It became a registered trademark in 1954, although Muzak broadcasting was around a couple decades before that. Muzak music has also played in doctors' offices, restaurants, government public service facilities, buses, retail stores, and even workplaces (to provide calm and cadence for workers). According to the Wikipedia entry, the term "Muzak " was coined by its inventor, George Owen Squier (Major General, ret.) as a play on the made-up term "Kodak;" i.e., "Muz" (music) + "ak." Over the years, a lot of scientific research went into Muzak's format including genre of music, tempo, silence ("dead") time, volume, etc. Muzak has changed hands many times, including to Westinghouse, until it finally declared bankruptcy in 2010. If you type "muzak.com" into your browser now, you get redirected to moodmedia.com ...

Skyworks Launches High Reliability Military and Space Solutions

Skyworks Launches High Reliability Military and Space Solutions - RF CafeSkyworks Solutions, an innovator of high performance analog semiconductors connecting people, places and things, today unveiled its latest high reliability solutions for demanding military and space applications with stringent operating requirements. Skyworks' hermetically sealed, broadband low-noise and impedance-matched amplifiers function in harsh environments and can be leveraged in a multitude of communication platforms. With all peripheral components integrated into an optimized ceramic QFN package, these devices simplify the design process and reduce board space while delivering robust performance for next ...

Sprint to Test Aerial HAPSmobile System for LTE Connectivity

Sprint to Test Aerial HAPSmobile System for LTE Connectivity - RF Cafe"Sprint plans to test a High Altitude Platform Stations (HAPS) communications system for six months starting in November. Documents filed with the FCC show the carrier has asked for a “special temporary authority” to conduct demonstrations of experimental transmitters using spectrum frequencies ranging from the 1.9 GHz personal communications service (PCS) band and the 2.5 GHz broadband radio service (BRS) and educational broadband service (EBS) bands. The tests will be conducted with HAPSmobile, a joint venture between Sprint's parent Softbank and AeroVironment that was formed in 2017 ..."

Electrical Meters - Why Meters?

Electrical Meters - Why Meters? NAVPERS 10622 Chapter 18 - RF CafeEven though most electrical meters have gone to a digital format, there are still many millions of analog meter movements doing service in equipment around the world. Analog meters are especially good for when the value being reported is changing rapidly and trying to read a numerical value would be tiring or impossible. A perfect example of comparing analog to digital is the Internet speed test display used by most companies. Run this speed test from Spectrum and watch the two indicator types simultaneously. Of course many pre-electronic meters are driven by sources other than electricity; e.g., fluid flow rate pressure meters, your bathroom scale, automobile speedometers, etc. A lot of modern "analog" meter indicator needles ...

TotalTemp Technologies: Thermal Platforms for −100°C to +200°C

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.

Tuesday 30

TRADIC - The "Super Computer"

TRADIC - The "Super Computer", June 1955 Popular Electronics - RF CafeThe TRAnsistor DIgital Computer (TRADIC) - or TRansistorized Airborne DIgital Computer for the airborne version - built in 1954, was the first transistorized computer. It might more aptly be called the first diode-ized digital computer since although it contained about 800 germanium transistors, there were more than 11,000 diodes used in the diode-transistor logic (DTL), diode logic (DL), and diode-resistor-logic (DRL) circuits. The TRADIC's construction benefitted in numerous ways over the vacuum tube computers it replaced, most notably in increased speed, smaller size, faster operations, higher reliability, greater safety (no high voltages), and lower power consumption ...

Leeds "The Home of Radio" Advertisement

Leeds "The Home of Radio" Advertisement, December 1931 QST - RF CafeLeeds, which dubbed itself "The Home of Radio," has been in New York since at least 1923, but this advertisement appeared in the December 1931 edition of QST. Leeds is still in operation today in Brooklyn under the name of Leeds Radio. Looking at the ad is a step back ninety years into the past, but the nostalgic waxing does not have to end there. If you want a trip back to the beginning days of the World Wide Web, go to the current Leeds Radio website. It's format-less text presentation with basic hyperlinks is circa 1992 when bulletin boards ruled the day and the Mosaic browser was just giving web surfers their first taste of a GUI ...

ConductRF Common Multiport RF Cables

ConductRF Common Multiport RF Cables - RF CafeWhy Re-invent the Wheel? These Multiport RF solutions have been tried and tested and you'd be surprised at the performance we can support today with this technology. Ideal for commercial and military applications. Combo D−Sub RF assembly solutions from DC to 18 GHz with RF contacts for #8, #12 and #16. D38999 RF assembly solutions from DC to 65 GHz, BMA, SMPM with #16, #12 and #8 contacts. Also support mixed signal requirements and common coax layouts.

Electronics-Themed Comics from Popular Electronics

All on Quarter-Inch Mylar, December 1966 Popular Electronics - RF CafeHere for your enjoyment during another workweek are three more vintage electronics-themed comics - this time from a 1966 issue of Popular Electronics magazine. The "quarter-inch Mylar" referenced in the title is recorder tape used in the very popular machines of the day. Not only were serious" music aficionados huge proponents of the medium, but so were the many recreational users. There was a sort of mystique involved with being able to record and instantly play back even normal conversations - sort of like with videos these days, except there is no mystique anymore because most users couldn't care less about the technology which enables their proclivities. The magazines of the era were full of stories on tape recorders and advertisements for buying them ...

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.

Tech Salaries Worldwide 2019

Tech Salaries Worldwide 2019 - RF Cafe"Whoooo-hooo! Silicon Valley companies pay their tech workers more than anywhere else in the world, with the average engineer in San Francisco pulling down $145,000 last year, according to Hired's annual report on the state of engineering salaries. And, according to Hired, Bay Area salaries are up over last year, by two percent. That's something for tech professionals in the area to cheer about, yes? Not exactly. That 2% just keeps tech workers even with the U.S. rate of inflation but puts them behind local increases in the cost of living, which is 4% as calculated by the Bureau of Labor Statistics for April 2018 through April 2019. And salaries in other tech heavy areas ..."

Custom MMIC: Off-the-Shelf and Custom MMICs

Custom MMIC- RF CafeCustom MMIC is a fabless RF and microwave MMIC designer entrusted by government and defense industry OEMs. Custom and off-the-shelf products include switches, phase shifters, attenuators, mixers and multipliers, and low noise, low phase noise, and distributed amplifiers. From next-generation long range military radar systems, to advanced aerospace and space-qualified satellite communications, microwave signal chains are being pushed to new limits - and no one understands this more than Custom MMIC. Please contact Custom MMIC today to see how they can help your project.

Monday 29

Carl & Jerry, Adventure in Electronics: The Sucker

Carl & Jerry, Adventure in Electronics: The Sucker, May 1963 Popular Electronics - RF CafeIn today's environment where law breakers seem to have more rights than law abiders, the electromechanical pyrotechnic tactic used in this story to snare a thief would have been used by a lawyer to charge Carl & Jerry (and Parvoo U. dorm mate Benny) with assault. A moronic judge would likely convict and fine (or jail) the boys trying to protect their own property and let the actual perpetrator - caught red-handed - walk. In fact, if we apply contemporary dictates on the treatment of property trespassers (i.e., the U.S. southern border), after getting into the car's trunk the law breaker would be given food stamps (EBT card), a nice hotel with large screen TV, clothing, and bestowment of sainthood. After all, he was just stealing property that other Americans wouldn't steal ...

Compliance Testing Seeking RF Test Engineers and Technicians

Compliance Testing Seeking RF Test Engineers and Technicians - RF CafeCompliance Testing has been providing worldwide compliance testing for FCC, IC and CE marks for over 50 years. We are currently seeking RF Test Engineers and Technicians with recent hands-on testing experience with spectrum analyzers, signal generators, network analyzers. Experience working on FCC standards for radios, transmitters and wireless devices. The candidate will have had experience testing using the test equipment listed above. Be able to research the applicable FCC or CE test standards, create test plans and work well with clients. Knowledge of applicable FCC or CE test standards, create test plans and work well with clients. Must have worked in regulatory testing at a test lab. Work comfortably with fully operating devices NOT just at component level ...

Meet Popular Electronics, October 1954

Meet Popular Electronics, October 1954 Popular Electronics - RF CafeOctober 1954 arrived with the first-ever issue of Popular Electronics. Editor Oliver Read wrote this introductory note describing the magazine's grand plans for providing its audience with a sampling of as many facets of electronics as possible, with projects for the do-it-yourself type (many needed to be at the time), related hobbies like amateur radio and radio controlled airplanes, military and commercial applications, short stories, tutorials, and an endless supply of advertisements offering just about anything your budget could afford. It turned out to be a pretty nice magazine, and many of the well-written articles are still useful in today's world of nano-everything circuits - the fundamentals haven't changed much: voltage still equals resistance times current ...

CTIA Touts U.S. Carriers' Investment in Spectral Efficiency

CTIA Touts U.S. Carriers' Investment in Spectral Efficiency"A new report by CTIA delves into the ways in which U.S. carriers have tried to squeeze the most efficiency out of their wireless spectrum, while continuing the industry's perennial call for the government to make still more available. U.S. wireless providers increased their spectrum efficiency by 42 times over what it was in 2010, according to the new white paper from CTIA. In 2010, the industry association said, U.S. wireless networks handled 948 million bytes per one megahertz of spectrum; now they handle 39.9 billion MBs/MHz, or more than 589,000 subscribers for each megahertz of spectrum ..."

Transient Specialists: EMC, EMI, RFI Test Equipment Rentals

Transient Specialists - RF CafeTransient Specialists specializes in EMC test equipment rentals and carries a complete line of ESD guns, surge immunity test equipment, and EFT generators. Rentals available for military (Mil-Std 461), automotive (ISO 7637), and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited calibrations and technical support on EMC testing equipment offered. Equipment consists of top EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and EMC Partner.

Sunday 28

Engineering & Science Crossword Puzzle for July 28

Engineering & Science Crossword Puzzle July 28, 2019 - RF CafeThis RF Cafe Engineering & Science Crossword Puzzle contains at least 10 words from headlines posted on the homepage during the week of July 22-26, 2019 (marked with an asterisk*). 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. Every word and clue - without exception - in these RF Cafe puzzles has been personally entered into a very large database that encompasses engineering, science, physical, astronomy, mathematics, chemistry, etc. Let me know if you would like a custom crossword puzzle built for your company, school, club, etc. (no charge).