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Homepage Archive - October 2018 (page 1)
See Page 1 | 2 | 3 | 4 | 5 of the October 2018 homepage archives.

Friday 2

Electronics IQ Quiz

Electronics IQ Quiz, May 1967 Popular Electronics - RF CafeUnlike those IQ tests conceived of and administered by Ph.D. college professors with pulsating veins in their foreheads, this "Electronics IQ Quiz," created by Popular Electronics quizmaster Robert Balin, is a true measure of your real-world acumen. Here are a couple hints to assist quiz takers not familiar with last century electronics. You need to have knowledge of the NTSC-mandated broadcast television channel bandwidth for figure A, but you might be able to guess it by process of elimination. For figure E, consider the bandwidth limits in terms of dB, not MHz. Kinks in the characteristic curves of the tube alluded to in figure D betray its number (extra hint: it's not a diode or a triode). Good luck...

Mini-Circuits' DIY Vector Network Analyzer Kit

Mini-Circuits' DIY Vector Network Analyzer Kit - RF CafeAn advertisement for Mini-Circuits' DIY Vector Network Analyzer Kit appeared in the October issue of Microwaves & RF magazine. It is evidently the first of a planned series of University Projects. Billed as an attempt to "Bridge the gap between textbook theory and real-world measurement," Project No. 1-UVNA-63 targets college laboratories as low-cost means of procuring a high performance vector network analyzer (VNA) at a reasonable cost ($2,495.00). The frequency range is 100 MHz to 6 GHz. Having the student build the 1-UVNA-63 provides a familiarity with a block diagram level understanding of 2-port VNAs and gives hands-on experience with assembling RF components. Included are filters, directional couplers, a transceiver PCB (made by Vayyar)...

Raytheon Numerical Indicator Tubes and Data Display Devices

Raytheon Numerical Indicator Tubes and Data Display Devices Advertisement, November 15, 1965 Electronics Magazine - RF CafeBefore there were side-view neon numerical indicator vacuum tubes there were top-view neon numerical indicator vacuum tubes. Nixie tubes and pixie tubes were featured in "Readouts and Counter Tubes" in the October 1959 issue of Electronics World magazine. At the time, most were top-view designs whose size was restricted by the diameter of the tube (typically about 0.8"). Switching to a side-view format did not enable the overall width to increase much, but the aspect ratio permitted taller displays with characters that appear as normally seen (rather than being squashed in height). This advertisement in a 1965 issue of Electronics magazine for numerical indicator tubes from Raytheon were likely some of the first side-view models available from any manufacturer...

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...

Free e-Book - 6 Rules of Effective Public Speaking

Six Rules of Effective Public Speaking - RF CafeIf you need to make presentations, advice in the free "Six Rules of Effective Public Speaking" e-book might be helpful. Great speakers don't just speak - they perform. Whatever type of speaking you do - in business, socially, or for personal pleasure - you're performing. We all perform roles day in and day out, every day of our lives. Public speaking is no different. To be effective in your speeches and presentations, accept this strong relationship between performance and success. In fact, the more you can connect with audiences rather than remaining in the comfort zone of your content, the more successful you'll be. Here are the Six Rules of Effective Public Speaking that will help you perform...

This Iceberg Is Perfectly Rectangular

This Iceberg Is Perfectly Rectangular - RF Cafe"Though it doesn't fit our typical image of icebergs, experts say the common shape has a simple explanation. In a world besieged by climate change-induced chaos and disruption, one satisfying image of order has emerged. It's an iceberg, shared online by NASA last Wednesday, that appears to be in the shape of a perfect rectangle with smooth, even walls, and 90-degree angles. The iceberg sits like a giant floating sheet cake near the east coast of the Antarctic peninsula. NASA's IceBridge aircraft spotted the iceberg during a routine aerial survey..."

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. Please visit Nova Microwave today...

Thursday 1

Radio Industry Marks 20th Anniversary - Harrisburg Telegraph c1940

Radio Industry Marks 20th Anniversary - Harrisburg Telegraph c1940 (Kirt's Cogitation #309) - RF CafeHello. My name is Kirt, and I'm a vintage magazine and newspaper addict. This affliction has had a hold on me for two decades now. Call it my middle age crisis. At sixty years old, there is no sign of abatement in enthusiasm. Nearly every day I still find myself reading and commenting on articles and advertisements from mid-last-century magazines, newspapers, and catalogs. Maybe I'm hopeless and will never be able to kick the habit. I'm not alone, though, based on some of the feedback received from RF Cafe visitors. For that reason and others, maybe, in truth, I've grown comfortable with my addiction. While perusing a few vintage newspaper editions from the World War II era looking for relevant stories, I ran across this November 1, 1940 (exactly 78 years ago) special section in the Harrisburg Telegraph titled, "Radio Industry Marks 20th Anniversary...

219 Modern Job Search Tips for 2019 - RF CafeDownload this free "219 Modern Job Search Tips for 2019" e-book! This 50-page resource covers over 20 topics, including: • Potential job search roadblocks • Characteristics of people who exude professionalism • Ways to purse a professional education beyond the classroom • Essential components of the modern job search • Interview prep tips from a world-class career coach • Powerful networking tools and strategies to adopt now • Ways to foster effective job interview conversations And much more! If you're searching for a new job to get a fresh start or advance your career, this eBook is for you...

Fairchild Instrumentation Scope Camera

Fairchild Instrumentation Scope Camera, October 18, 1965 Electronics Magazine - RF CafeAre you old enough to remember when in order to make a measurement on a circuit board it was necessary to physically connect an oscilloscope probe to a trace or component lead? "Wait," you say, "What are you talking about? You still do have to physically connect a probe." Right you are, but 50 years from now your progeny will be asking that question, just as today I ask you do you remember when in order to get a "screen shot" of an o-scope or spectrum analyzer display it was necessary to connect a camera to the front of the CRT? Some instruments had an(a) output port(s) for driving a pen plotter, but getting a plotter set up and calibrated was often more work and frustration than hanging a camera on the front. Most of the cameras used Polaroid film packs to enable "instant" pictures...

Many Thanks to Nova Microwave for Continuing Support!

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. Please visit Nova Microwave today...

Anatech Electronics End-of-October Product Update

Anatech Electronics Product Update October 30, 2018 - RF CafeAnatech Electronics, Inc. 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. Anatech has introduced three new filter designs: a combination 12-20 MHz bandstop / notch filter with SMA connectors, a 8.5-18 GHz highpass filter with N-type connectors, and a surface mount 4,450 MHz ceramic bandpass filter. Custom RF filters designs are used when a standard cannot be found, or the requirements are such that a custom approach is necessary...

everythingRF Website Services: Website Design & Hosting

everything RF Website Design Services (78x26)everything RF is now offering website development services! Get a new website or upgrade your existing website - All for only $99/month (can go up to $299/month based on the number of products). There is no design or development charge, nor is there a lock-in or contract. There is a simple monthly cost which includes everything - design, development, hosting, backups, data porting and anything else. You do not need to hire an agency and spend thousands of dollars to create a website...

MathWorks Rolls Out 5G Modeling and Simulation Package

MathWorks Rolls Out 5G Modeling and Simulation Package - RF Cafe"New product is believed to be the first commercially available 5G modeling tool since the finalization of the new 5G radio standard in June. A new simulation tool from MathWorks promises to speed development, prototyping, and testing of 5G cellular networking systems. The new 5G Toolbox, an add-on to the company's well-known MATLAB simulation environment, is aimed at 5G system architects, as well as engineers who are developing the digital, RF, and antenna systems for 5G. "It gives engineers a way to understand the underlying technology in the 5G standard very quickly," Ken Karnofsky, senior strategist for signal processing applications at MathWorks..."

Wednesday 31

Transmitters Towed Through Air Tests Antenna's Radiation Pattern

Transmitters Towed Through Air Tests Antenna's Radiation Pattern, October 18, 1965 Electronics Magazine - RF Cafe"Xeledop" is the Word of the Day for October 31; use it often. Xeledop is an acronym for "transmitting elementary dipole with optional polarity." Nope, I've never heard of it, either. The Xeledop (probably pronounced "zeh'-le-dop") is an air-towed transmitter that flies a pre-planned path around the ground-based antenna under test (AUT) whose radiation pattern is being measured. The circular power level plot at the bottom of the page shows the results of an actual test flight. In this application, a high frequency (HF, 3-30 MHz) transmitter is towed behind an airplane like target drone while it broadcasts signals at eight distinct frequencies toward the AUT, while the downstream receiver records power levels. The pilot flies on the surface of an imaginary hemisphere to maintain a constant radius from the antenna. Ground equipment tracks the aircraft azimuth and slant range is calculated using aircraft altimeter data and measured elevation angles...

2018 Microwaves & RF Salary & Career Report

2018 Microwaves & RF Salary & Career Report: Education - RF CafeMicrowaves & RF is publishing its 2018 Salary & Career Survey results in installments, with the first part dealing with job satisfaction in August. Part two - this one - focuses on education. "The main question for this section of the survey asked: "How are engineers maintaining their education?” According to the results, white papers are the leading source - 73.8% of respondents take advantage of them. This should come as no surprise given the amount of white papers circulating out there, and the fact that, for the most part, they're easily accessible. Magazines are the second-leading source, with 72.2% saying that they read magazines to sustain their education. Websites, webinars..."

A Selected History of Receiver Innovations over the Last 100 Years

A Selected History of Receiver Innovations over the Last 100 Years (Part 2) - RF CafeIn Part 2 of "A Selected History of Receiver Innovations over the Last 100 Years," author Brad Brannon discusses superheterodyne circuits and multiple conversion stages. "One key point early radio pioneers like de Forest and Armstrong understood was that their successes were determined by a solid, reliable detector. In the early days, this was largely the wireless operator, whose technical and auditory skills made it possible. However, as the industry grew, other aspects became important, such as including linearity and bandwidth. In 1912, to address these issues, de Forest figured out regeneration and how a receiver could benefit from this technique. At nearly the same time, Armstrong made similar discoveries, and he noted that if energy was coupled from the plate circuit back into the screen tuner, significant amplification occurred as the amplifier response peaked prior to free oscillation..."

Many Thanks to Reactel for Their Long-Time Support!

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...

Japan: An Industrious Competitor

Japan: An Industrous Competitor, October 4, 1965 Electronics Magazine - RF Cafe"Japanese electronics firms' real strength is their engineers, characterized by creativity, ingenuity and an awesome willingness to work long and hard." That statement by editor Lewis Young is the key point in this article that appeared in a 1965 issue of Electronics magazine. That Japanese technology companies were deemed to be only about five years behind the U.S. was a real wake-up call to America and the European countries. Both Europe and Japan had been very diligent about rebuilding and modernizing techniques and infrastructure since the destruction caused by World War II. A few stories about Japan's post-war efforts report on how the government left most of the responsibility (aka financing) up to universities and private companies. Industry in some of the more...

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...

10 Scary True Stories from Engineering History

10 Scary True Stories from Engineering History - RF CafeJust in time for Halloween... "Resurrecting the dead, mind control, radiation gone wrong, and man-eating robots, we've rounded up 10 of history's creepiest true tales of science and engineering gone wrong. Some of your favorite horror movies have nothing on the real thing. History is full of plenty of true-to-life tales of mad science. Whether it was malicious or unintentional, the effect is the same and the stories here are certified nightmare fuel. From experiments gone wrong to misguided inventions and occult rituals, you won't believe some of the things that have happened in the name of science..."

Tuesday 30

Phase Noise Reference Page Added

Phase Noise Explanation & Equations - RF CafePhase noise measurements quantify the short term stability of a frequency source. That is because phase and frequency are mathematically related by a differential function [ω(t) = dΦ(t)/dt] so they are directly connected. Phase noise also includes amplitude instability due to atomic scale effects like FM flicker noise (1/f3), white noise (1/f2), PM flicker noise (1/f), and possibly even voltage supply noise (typically discrete spurs). When the frequency source is used as a local oscillator in a frequency converter (up- or down-), the amount of instability (jitter) is modulated onto the transmitter or received signal. While not usually a major concern in analog systems, in high speed digital communication systems phase noise can degrade the ability of the receiver to correctly determine the difference between a "1" and a"0." That is because...

Algorithms to Antenna: Modeling Polarization in Radar and Wireless Systems

Algorithms to Antenna: Modeling Polarization in Radar and Wireless Systems - RF CafeHow do you analyze antenna polarization? Rick Gentile provides an answer in his Microwaves & RF magazine article titled, "Algorithms to Antenna: Modeling Polarization in Radar and Wireless Systems." Says Rick, "In this blog, I describe polarization and explore ways you can analyze the polarized field as well as model the signal transmission between polarized antennas and targets. From Maxwell's equations, the electromagnetic (EM) field generated by an antenna is orthogonal to the propagation direction in the far field. The field can be decomposed into two orthogonal components. The most common representations of these components are either horizontal and vertical (H, V) sets or left and right circular (L, R) sets..."

Many Thanks to Res-Net Microwave for Continuing Support!

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...

$15 Federal License Fee for Telephone Users?

$15 Federal License Fee for Telephone Users?, November 15, 1965 Electronics Magazine - RF CafeIf you have read as many vintage electronics magazines as I have, one thing that is obvious is how many of the same issues that plagued the field since the middle of the last century are still with us today - only in a much worse way by now. Government meddling, regulation and taxation are amongst the top offenders. Both the electric power industry and the communications industry have been hit hard, and huge costs to consumers is the result. Itemized bills from the utility companies do not give the full picture of what a large percentage of your monthly premiums go to feed the government beast. You might see some line items for taxes, surcharges, contributions and user fees, but those being paid for you by the providers (i.e., absorbed in the base charge) are hidden. One of the more recent, highly publicized example...

Phase Noise in Direct Downconverters and Radar Systems

Phase Noise in Direct Downconverters and Radar Systems - RF CafeThe Custom MMIC company has an article in Microwave Product Digest magazine titled "Addressing Phase Noise in Direct Downconverters and Radar Systems with New LPNA MMICs." It provides a quick review of the nature of phase noise. "Phase noise is becoming an increasingly critical factor needing to be addressed in sophisticated radar and communication systems. This is because it is the key parameter defining both target acquisition in radars and spectral integrity in communication systems. There are many papers detailing the mathematical derivation of phase noise, but few mention the reason for its importance or what can be done to lessen its effects..."

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. Please visit Anatech today to see how they can help your project succeed...

Conductive Properties of Bismuth for Electronics Applications

Conductive Properties of Bismuth for Electronics Applications - RF Cafe"European scientists have discovered that thousands of materials - including bismuth - have the potential to replace silicon in advanced electronic and computing applications. Scientists are constantly searching for new materials called topological insulators, due to their unique ability to insulate on the inside but conduct electrical current on their surface. This property allows an electrical current to theoretically flow without resistance and respond in unconventional ways to electric and magnetic fields. Recently, a team of researchers made an unexpected discovery in this field that proves that the widely used material..."

Monday 29

How to Improve PCB Design for Bluetooth Circuit Boards

San Francisco Circuits App Note: How to Improve PCB Design for Bluetooth Circuit Boards - RF CafeSan Francisco Circuits, a leading provider of printed circuit board fabrication and assembly, has published an application note titled, "How to Improve PCB Design for Bluetooth Circuit Boards." Their experience in assisting customers in successful layouts for substrates operating in the RF frequency realm. How to Improve PCB Design for Bluetooth Circuit Boards Bluetooth Circuit Board Design Guidelines Printed circuit boards with Bluetooth technology can be problematic with interference, lost data and poor signal integrity if certain precautions aren't taken. We'll outline many rules and guidelines to consider when choosing Bluetooth technology for a given application and, more specifically, designing it into a circuit board. A variety of applications utilize Bluetooth, including: Beacons used in shopping malls...

The GPS Week Number Rollover Problem - Y2K Redux?

The GPS Week Number Rollover Problem  - Y2K Redux? - RF CafeAn RF Cafe visitor - I'll call him Mr. X - is privy to and has a vested interest in GPS-related issues. He sent me a link to this "The GPS Week Number Rollover Problem" article last Friday which is posted on the Spirent Blog website. Did you know that the original GPS had a 10-bit date code that lasts for just 1,024 weeks (19.7 years)? Those of us who were around for the big Y2K scare remember this scenario (we're "survivors" in modern psychopathic lingo). Per author Guy Buesnel, "Some GPS receivers may malfunction on or after 6 April, 2019, due to the GPS Week Rollover. Here's what that means and how to check if a receiver is vulnerable. If your vehicles or equipment rely on GPS receivers, now is the time to check if they're affected by the GPS Week Number Rollover issue..."

Skyworks Wins 2 Mobile Breakthrough Awards!

Skyworks Wins Two Mobile Breakthrough Awards! - RF CafeSkyworks Solutions, an innovator of high performance analog semiconductors connecting people, places and things, is excited to share that several of Skyworks' innovative solutions have received top honors from Mobile Breakthrough. Mobile Breakthrough recognizes the world's best mobile and wireless companies, products and people based on selections from an independent panel of experts within the wireless industry. It is an honor to have been selected from amongst over 2,200 nominations for developing leading-edge technology. Skyworks' family of advanced GNSS low-noise amplifier front-end modules, which were named "GPS-based Solutions of the Year," provide global manufacturers with a compact, turnkey connectivity...

Washington Newsletter, October 18, 1965 Electronics Magazine

Washington Newsletter, October 18, 1965 Electronics Magazine - RF Cafe1965 was the beginning of America's involvement in Vietnam. A mere decade had passed since the end of the Korean War (or "conflict" if you prefer), and the Department of Defense had not done much to modernize the military since then. Unlike with World War II when U.S. factories were turning out military aircraft, ships, and ground vehicles ahead of formal involvement, Congress was not interested in making headlines with news of war machines. The "Washington Newsletter" feature of this October 1965 issue of Electronics magazine reported on, among other military-related items, the U.S. Air Force's plans to phase out the venerated B-52 Stratofortress bomber by sometime in the 1970s. Here it is half a century later and the B-52...

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...

Wanted: Wearable Warfighter Wireless Communications

Wanted: Wearable Warfighter Wireless Communications - RF Cafe"U.S. Army researchers are surveying industry for companies able to design a secure small, lightweight wireless communications module to tie together wearable electronics on the individual infantry warfighter without eavesdropping or interference from the enemy. Officials of the Army Contracting Command at Fort Belvoir, Va., issued a source-sought notice on Tuesday (W909MY-19-R-0002) for the Secure Intra-Soldier Wireless Module with Reduced Size and Power (ICW Chipset) project. Intra-soldier wireless (ICW) technology seeks to link pieces of the infantry warfighter's kit, such as wearable computers, radios, and electro-optical rifle sights..."

Sunday 28

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...

Friday 26

Electromaze Puzzle, February 1966 Popular Electronics

Electromaze Puzzle, February 1966 Popular Electronics - RF CafeRobert Radford's (not to be confused with Robert Redford) "Electromaze Puzzle" is a unique - and weird - sort of word puzzle that first appeared in this February 1966 issue of Popular Electronics magazine. Some people have been confused about the strategy, believing that all the white spaces needed to be filled in. They do not. Just because a letter might have an empty square adjacent to it does not imply that another letter must fill it. Also, read the instruction carefully, especially the part about the last letter of one word being the first letter of another word. You will probably want to print out the maze grid and find an old guy who should still have a pencil stowed away somewhere you can borrow to use for filling in the boxes...

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