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Homepage Archive - September 2019 (page 3)

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.

Homepage Archive Pages

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2019:
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2018:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
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See Page 1 | 2 | 3 | 4 of the September 2019 homepage archives.
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Friday 20

Basic Digital Logic Course - Part 3

Basic Digital Logic Course, December 1974 Popular Electronics - RF CafeHere is the final installment in the "Basic Digital Electronic Course" series that ran in three issues of Popular Electronics magazine. The first two parts laid the groundwork with an introduction to binary, octal, and hexadecimal arithmetic, Boolean logic, AND, OR and NOT gates, and some truth tables. Armed with those fundamentals, the authors now dive into flip-flops, encoders and decoders, debouncing circuits for switch inputs, integrated circuit (IC) types, and interconnect methods to design and build a simple digital computer with a 7-segment LED display. Don't expect too much from the computer since it was only three years earlier, in 1971, that Intel introduced the world's first integrated microprocessor - the 4-bit model 4004 central processing unit (CPU) ...

Notable Quote: Steve Ford, WB8IMY

Steve Ford, WB8IMY, Notable Quote - RF Cafe"It was made clear that I was not to touch this sacred totem, especially the threaded rods..." - Steve Ford, WB8IMY, in an article entitled, "Duplexers & Diplexers," in the October 2019 issue of QST magazine. That statement was made in regard to a cavity-tuned duplexer that was part of a Ham radio repeater installation. Mr. Ford, a monthly columnist, discusses the difference between a duplexer and a diplexer. A pull quote from the piece is, "If you're about to pay less than $100 for the device in question, it is a diplexer. If the price tag has four digits to the left of the decimal, it is a duplexer." Do you agree with that generalization? Unfortunately, the ARRL does not make the magazine articles available to non-subscribers.

PMI's September 2019 Product Announcement

Planar Monolithic Industries (PMI) September 2019 Product Announcement - RF CafePlanar Monolithic Industries (PMI) recently introduced six new products in their extensive line of RF and microwave components. Included are a successive detection log video amplifier (SDLVA) for 0.1 to 2.0 GHz; a 18 GHz, 12-BIT, vector phase shifter; a digital frequency discriminator (DFD) for 20 to 18.0 GHz, a 100 MHz amplified 8-way power divider, a 7-bit programmable attenuator for 1.0 to 18.0 GHz, a 0.1 to 50.0 GHz SP16T absorptive switch, and a Frequency Discriminator for 0.5 to 1.5 GHz. Contact PMI today for more information ...

The Rest of the Story, by Paul Harvey

The Rest of the Story... (a la Paul Harvey) - RF CafeAs a long-time Paul Harvey fan, I used to listen to his radio news broadcasts and especially looked forward to his "The Rest of the Story" pieces. It was a challenge to listen and try to figure out who or what the alluded-to person, place, or thing at the end of the the story would be. In honor of Mr. Harvey, who left this Earth in 2009, the following Smorgasbord about featured celebrity "Sam" is fashioned after his trademarked style. As is often the case with people of accomplishment, this subject's talents extended beyond the skill for which he is most known. An article in the September 2011 Smithsonian magazine inspired the research ...

Piezo-Based Approach Dramatically Shrinks VLF Antennas

Piezo-Based Approach Dramatically Shrinks VLF Antennas - RF Cafe"A research team developed VLF antennas using piezoelectric material and principles, resulting in an antenna that's far smaller than metal antennas, thus overcoming a major impediment to VLF links. While everyone is focused on RF signals in the gigahertz-plus range, it's important to remember that the other end of the electromagnetic spectrum also has its uses. However, signals in very-low-frequency (VLF) RF band present a technical dilemma: On one hand, you can't easily live with them; on the other, you can't live without them for some applications cases. The former assessment is due to their need for extremely large antennas (on the order of kilometers). The latter assessment is a result of their propagation characteristics, including Earth-hugging signals and low atmospheric attenuation, as well as their ability to penetrate seawater ... "

San Francisco Circuits: PCB Fabrications & Assembly Service

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.

Thursday 19

Einstein Expounds on His New Theory - NY Times

Einstein Expounds on His New Theory, 12/3/1919 The New York Times - RF CafeOn the heels of searching for the first mention of Nikola Tesla in U.S. newspapers, I performed a similar search on Albert Einstein, again using editions available in the NewspaperArchive.com database. I was utterly surprised to find it in a 1919 issue of the The New York Times. His theory of Special Relativity was published in 1905 and his theory of General Relativity was published in 1915, so it took The NY Times four years to mention it. There is a reference to Dr. Einstein's' work on relativity in a 1915 edition of The Manitoban*, from Winnipeg, Canada. The New York Times article is an actual interview with Albert Einstein, wherein at one point it is stated that there were perhaps only a dozen people in the world at that time who understood general relativity. Interestingly, Einstein uses the term "difform motion" to describe what we now call "non-uniform motion ..."

Radar "Sidelight"

Radar "Sidelight", December 1955 Popular Electronics - RF CafeWhen I saw this photo of a man holding a fluorescent light bulb in the beam of a radar antenna, it reminded me of how we used to do the same thing on our AN/MPN-14 radar system in the USAF. The unit in the photo is a General Electric's FPS-6 height-finding radar, which operates in the S-band 2,700-2,900 MHz region. The AN/MPN-14 is a mobile ground control approach (GCA) with both an S-band airport surveillance radar (ASR) and an X-band precision approach radar (PAR). Our S-band radar had a 600 kW peak power whereas the FPS-6 put out a couple megawatts, but 600 kW was enough to light the bulb. Of course these days you would never see a company-sponsored photo of a man standing in front of a high power radar antenna with a fluorescent light bulb in his hand ...

Top 20 Countries by Number of Internet Users

Top 20 Countries by Number of Internet Users - RF Cafe Video for EngineersHere is a really interesting animation of the world's top 20 country ranked by the number of Internet users in those countries. It runs (as of this posting date) from 1990 through 2019. I have not verified the numbers used by the Animate Stats producers, but the results do not seem unreasonable. Given the the U.S. Department of Defense's research arm, Defense Advanced Research Projects Agency (DARPA), created the Advanced Research Projects Agency Network (ARPANET) that eventually became the Internet, showing the U.S. as the run-away leader in the beginning is not surprising. Around 1996, things begin to change quickly as Japan advances, but it is in 2000 when the Internet user landscape really becomes dynamic ...

1957 Auto Radios: Chevrolet

1957 Auto Radios: Chevrolet, April 1957 Radio & TV News - RF CafeApologies to Chrysler aficionados for not having similar articles for your classic automobiles, but this article from a 1957 edition of Radio & TV News only covers Chevrolet radios. Maybe someday I will acquire editions with other models. Transistors were fairly recent newcomers on the portable radio scene (on any radio scene for that matter), so you will please excuse the absence of them in most radios of the era. In fact, as evidenced by a companion article in this same edition titled "Delco's All-Transistor Auto Radio," such newfangled devices like transistors were reserved for top-of-the-line models like Cadillac's Eldorado Brougham. A move toward printed circuit boards, rather than the time-honored point-to-point wiring, was well underway, and push-button tuning was being sold to the car buying public as an indispensible safety feature ...

ConductRF Rugged Replacement VNA Cables

ConductRF Rugged Replacement VNA Coaxial Cables - RF CafePrecision Ruggedized VNA Cables from ConductRF offer RF Engineers great alternatives to costly OEM cables that are now past their best days. We have standards for applications at 18 GHz, 27 GHz, 40 GHz, 50 GHz & 70 GHz. Our torque resistant connector heads and phase stable constructions ensure great performance for many tests to come. 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, these cables offer cost leading alternatives to original OEM VNA cable solutions. VNA Series cables are enhanced with a stainless steel spiral armor ...

Wi-Fi 6 Industry Impact Report

Wi-Fi 6 Industry Impact Report - RF Cafe"To hear technologists describe it, Wi-Fi 6 is about to transform connectivity. The next-generation Wi-Fi connectivity technology - along with the emerging 5G cellular generation - will shake up the way we connect with each other. The ability of Wi-Fi 6, or 802.11ax, to instantly route traffic - even to devices on the far reaches of very crowded networks - will also change the way we interact with our smart devices. It will even rework the way smart devices communicate with each other. But from what we've seen thus far, Wi-Fi 6 is emerging on the scene in much the same manner as previous generations of wireless technology: integrated inside the latest smartphones and laptops. And in new routers and access points that promise faster ..."

Alliance Test Equipment: Used & Refurbished, Purchase & Rental

Allied Test Equipment Products - RF CafeAlliance Test 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. Please visit Allied Test Equipment today to see how they can help your project.

Wednesday 18

The Ray of Mystery - Tesla & Röentgen

The Ray of Mystery - Tesla and Röentgen, 3/15/1986 The Warren Mail - RF CafeOn a whim, I did a search for the earliest appearance of Nikola Tesla's name in U.S. newspapers included in the NewspaperArchive.com database. This story from Mr. George Grantham Bain appeared in multiple newspapers within a few days of this March 5, 1896 edition of The Warren Times in Warren, Pennsylvania, which coincidentally is only a few miles from me here in Erie. The article reports on the role that Tesla's high voltage generators played in the development of x-ray images on fluorescent displays and on film (which Tesla termed "cathode photography"). It mentions how the term "cathode" is relatively new to the general public even though it had been around since 1832 when Michael Faraday introduced it in his work. Wilhelm Röentgen made the world's first x-ray image ...

1957 Auto Radios: Ford

1957 Auto Radios: Ford, July 1957 Radio & TV News - RF Cafe1957 was part of the heyday of the newfound radio-in-your-car craze, and the public was voraciously consuming all the high tech equipment it could afford. Rock and Roll music was on every teenager's mind and many guys for the first time were able to have their own wheels and were outfitting them with sound systems that could blast the latest works of Buddy Holley, Chuck Berry, Elvis Presley, and Fats Domino. Those machines were the first babe magnets used for cruising the strip on Saturday nights. Radio stations were popping up all over the country, enabling cross-country travel with non-stop music, news, and variety show entertainment. Ford and Chevrolet were not going to miss an opportunity, so they delved into the high end mobile radio manufacturing business ...

Thanks to QuinStar Technology for Their Support

QuinStar Technology mm-Wave Products - RF CafeQuinStar Technology designs and manufactures mm-wave products for communication, scientific, and test applications along with providing microelectronic assembly, rapid prototyping, and mass customization. Amplifiers, Oscillators, Switches, Attenuators, Circulators, Isolators, Filters, Waveguide, Antennas, Phase Shifters, Transceivers, Mixers, Detectors. QuinStar specializes in cryogenic amplifiers, circulators, and isolators. Please visit QuinStar today to see how they can help your project.

An Accurate Voltage Divider

An Accurate Voltage Divider, May 1957 Radio & TV News - RF CafeIt took me a couple passes of the explanation to comprehend the advantage of a Thomson-Varley (aka Kelvin-Varley, since Thomson and Lord Kelvin are one and the same person) switchable voltage divider compared to a standard type. At first I thought the author, Edwin Bohr, was implying that the source and load impedances would not have as great of an effect on the accuracy of the divider (and to some extent it is less sensitive), but the main advantage is that the configuration permits simple cascading stages of decade dividers to achieve essentially any degree of resolution. Both a standard series-wired type voltage divider and the Thomson-Varley need ten resistors ...

* Health Fears Prompt Swiss 5G Revolt *

Health Fears Prompt Swiss 5G Revolt - RF CafeRuh-roh. "Switzerland was among the first countries to begin deploying 5G, but health fears over radiation from the antennas that carry the next-generation mobile technology have sparked a nationwide revolt. Demonstrators against the technology are due to fill the streets of Bern later this month, but already a number of cantons have been pressured to put planned constructions of 5G-compatible antennae on ice. The technology has been swept up in the deepening trade war between China and the United States, which has tried to rein in Chinese giant Huawei - the world's leader in superfast 5G equipment - over fears it will allow Beijing to spy on communications from countries that use its products and services ..."

VidaRF: Passive RF & Microwave Components

vidaRF passive RF & microwave components - RF CafeAt VidaRF, the phrase 'Providing Simple Solutions for Complex Connections' is more than just a slogan – it's a mindset, a mission, and a driving force behind everything we do. Their pledge is to design and distribute high performance, cost effective RF Microwave products to fit each customer's unique applications. Please visit VidaRF today to see how their lines of attenuators & terminations, directional couplers, power dividers, coaxial connectors, and circulator & isolators can be of use to your project. "When the standard just will not do, VidaRF has the solution for you!"

Tuesday 17

Basic Digital Logic Course - Gates & Circuits

Basic Digital Logic Course, November 1974 Popular Electronics - RF CafeEnglish mathematician George Boole published his "Formal Logic" syllogism system of deductive reasoning in 1847. Fellow countryman Augustus De Morgan followed on Boole's work to develop the basic combinational logic rules the AND gates, OR gates, and NOT (negation) operators. What has become known as Boolean algebra and De Morgan's theorem forms the fundamental foundation of everything related to digital logic. This second in a three-part series from a 1974 issue of Popular Electronics introduces both concepts at a beginner's level. Part 3 will present flip-flops and an overview of how all the parts come together to build a simple computer.

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

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 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 ...

Linx Technologies Intros SP610 Splatch® Antennas

Linx Technologies Intros SP610 Splatch® Antennas - RF CafeLinx Technologies, a Merlin, OR based developer and manufacturer of antennas, is pleased to introduce the Splatch® SP610 antennas. The Splatch® SP610 is a surface mount monopole antenna for embedded LTE and cellular IoT (LTE-M and NB-IoT) applications. It specifically supports low-frequency LTE bands from 698 MHz to 960 MHz, notably the 700 MHz bands, and 1710 MHz to 2700 MHz making it an outstanding antenna for LTE and cellular low power wide-area (LPWA) applications in North America, Europe and worldwide. The SP610 uses a grounded-line technique to achieve outstanding performance when subject to nearby sources of interference ...

Anatech Electronics September 2019 Newsletter

Anatech Electronics September 2019 Newsletter - RF CafeSam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his September newsletter that features his short op−ed entitled "Interference: 5G Hits a Snag." He mentions the unavoidable issues that are being faced by telcos trying to deploy their 5G infrastructure that operates in the millimeter-wave bands. The two most notable difficulties are that of expensive equipment costs and relatively short propagation distances (per Mr. Friis' equation). It is the latter that is partly responsible for the former difficulty because shorter ranges translate to needing more closely spaced cells. Re-allocation of some existing bands is inevitable, which worries Hams more than just a little since their spectrum privileges seem to uninformed bureaucrats to be ...

Learn from Men Who Are Pioneering Electronics

Learn from Men Who Are Pioneering Electronics, July 1959 Popular Electronics - RF CafeHere is a recruitment advertisement published by the the U. S. Army in the July 1959 edition of Popular Electronics. This was only a few years after the Korean War ended in 1953 and a couple years before we got involved in the Vietnam War in 1961. It's always interesting to see what the mindset about the current state of electronics was many moons ago, and to compare it with today's technology. In the same manner, people 60 years from now will look at today's recruitment ads and be amazed at how relatively crude our contemporary state of the art is.

Top 5 Causes for Project Fatigue

Top 5 Causes for Project Fatigue - RF Cafe"There are numerous causes for projects to break down. Five of the common causes include never-ending debugging cycles, stop-and-go projects, projects that are more difficult than anticipated, projects that go past deadline, and projects that force overtime. Project fatigue can have a crippling effect on the project development cycle. A project starts and the development team is energized and dive in with positive fervor, but before long, the project stalls and seems to be going nowhere fast. There are dozens of potential causes for project fatigue, but in my experience, there are five main causes that result in project fatigue for developers. Let's examine these causes. "

RF Superstore: Supplier of RF & Microwave Components

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 $99. We're leading the way again!

Monday 16

Basic Digital Logic Course - Number Systems

Basic Digital Logic Course, December 1974 Popular Electronics - RF CafeThis first of a three-part series on digital electronics run by Popular Electronics magazine begins with introducing binary (base 2), octal (base 8), and decimal (base 10) number systems, along with conversions between the types. Sure, this is probably old-hat to most RF Cafe visitors, but there is always a new cadre of electronics enthusiasts entering the field who appreciate the instruction. No matter how advanced digital electronics gets, a fundamental understanding and fluency in binary arithmetic is essential to success whether as a hobbyists or as a professional. If you cannot move effortlessly between the various number formats (which also include hexadecimal and Gray code), then continuing to Boolean algebra ...

Sylvania Electric Duo Diode

Sylvania Electric Duo Diode, July 1946 QST - RF CafeWhen semiconductor devices first came onto the electronics scene, there was a lot of resistance (pun intended) to adopting and designing them into circuits. Some of the reluctance (doh, another intentional pun) was justified in that reliability could be an issue, due primarily to the mechanical contacts that interface wire leads to the semiconductor elements. In an effort to mitigate some of the fear of a new type of component, often times familiar names were given to them, such as with this duo-diode. Duo-diode vacuum tubes, the integration of two separate diodes into a single glass enclosure, were commonly used in balanced signal detectors because it was a way to achieve nearly exact performance in the pair that would track equally even as the tube ...

Webinar: Overcome the Challenges of mmWave

Overcome the Challenges of mmWave - RF CafeKeysight Technologies just announced the availability of of a new, free webinar entitled, "Overcome the Challenges of mmWave." "The move to millimeter-wave doesn't come easily. There are new techniques required, and with these new techniques come a number of testing challenges you've likely never encountered. Are you ready? In this pre-recorded webcast, Pete Cain, Wireless Solutions Planner at Keysight Technologies, one of the foremost experts in this field, walks you through the challenges of millimeter-wave. Get an overview of the applications, and the spectrum and device under test before moving into a variety of measurement related issues."

1992 Honda Radio Teardown

1992 Honda Radio Teardown - RF CafeYou know you're old when a 1992 car radio does not seem like it should qualify as a vintage electronics. Electronic Design's Paul Rako has posted his findings when investigation a failed AM/FM radio from his 1992 Honda car. "The radio in my 1992 Honda started acting up a decade ago. The display went out first. Pressing or hitting the front panel brought it back, at least for a while. Then the tuner was intermittent, no matter if the display was working. Four years ago, the radio really broke. It would not play at all; worse yet, there would be loud RF squealing in the speakers, even with the radio turned off. I assumed this was from a blown output section that was receiving electromagnetic interference (EMI), which the blown transistors would rectify and detect ..."

Reactel: RF & Microwave Filters of All Types

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

Sunday 15

Engineering & Technical Headlines Crossword Puzzle for September 15

Engineering & Technical Headlines Crossword Puzzle September 15, 2019 - RF CafeThis RF Cafe Engineering & Technical Headlines Crossword Puzzle contains at least 10 words from headlines posted on the homepage during the week of September 9 through September 13, 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).

Anatech Electronics (RF Filters) - RF Cafe PCB Directory (Assembly)
Exodus Advanced Communications - RF Cafe Res-Net Microwave - RF Cafe
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Copyright: 1996 - 2024
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    Kirt Blattenberger,
    BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while typing up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

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