Homepage Archive - December 2020 (page 4)

Monday 28

Superior Instrument Company Advertisement

Sometimes I post advertisements such as this one for vintage test equipment from a 1938 issue of Radio News magazine just so people can see how much things have changed, and how good we have it with today's compact, highly functional products. These Superior Instrument Company multimeters, signal generators and vacuum tube testers were truly superior instruments considering the materials and methods available at the time. Chassis were made from sturdy wood or metal (not much plastic then), and the finishes were often of very attractive stain and varnish, fabric lamination, paint, or a combination thereof. Price-wise, the Model 1110-S A.C. - D.C Volt Ohm Milliammeter price tag of $7.95 in 1938 is the equivalent of $147.77 in today's money, which is not unreasonable for a superior instrument...

Many Thanks to ConductRF for Continued Support!

ConductRF is continually innovating and developing new and improved solutions for RF Interconnect needs. See the latest TESTeCON RF Test Cables for labs. ConductRF makes production and test coax cable assemblies for amplitude and phased matched VNA applications as well as standard & precision RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the iBwave component library. They also provide custom coax solutions for applications where some standard just won't do. A partnership with Newark assures fast, reliable access. Please visit ConductRF today to see how they can help your project! 

A Review of Transmission Lines as Circuit Elements

Mr. Wilfred Jensby wrote an incredibly detailed article for the November 1966 edition of QST that delves deeply into the subject of using transmission lines as distributed circuit elements. I did a search on his name, figuring that he likely had other publications of like sort, but nothing was found. Information contained herein is similar to what you would expect to find in a Master's level engineering course textbook or in a $100+ technical book from Artech House, Cambridge University Press, John Wiley & Sons, etc. The brain-zapping equations are omitted with only a great, layman-level discussion of the concepts and some really nice illustrations and graphs. This is definitely an article you will want to check out and pass on to colleagues...

Exodus Advanced Communications Intros 80-1000 MHz, 1100 W SSPA

"Exodus-Advanced-Communications-AMP2085C-SSPA-9-2-2020.htm" target="_top"> Exodus Advanced Communications' AMP2071A-LC, 80 to 1000 MHz, 750 Watts with our Quiet-Cool Technology Exodus AMP2071A-LC is a powerhouse in a compact chassis! Covering 80-1000 MHz, produces >750 W minimum, >1100 W nominal power, P1dB >500 W minimum. Excellent gain flatness with a minimum power gain of 58 dB. Included are amplifier monitoring parameters for forward / reflected power, VSWR, as well as voltage, current & temperature sensing for optimum reliability & ruggedness. Nominal weight is <40 kg, and dimensions of 19"W x 22"L x 8.75"H. Features Class A/AB linear LDMOS design Instantaneous ultra-wide bandwidth Rack mounted system Designed for broadband EMI/RFI, Lab, Communications and EW applications Suitable for all single channel modulation standards Built-in protection circuits...

A Redux of the Venerable Vacuum Tube?

Vintage radio fans will be interested in this news article entitled, "NASA scientists design a nanoscale complementary vacuum field emission transistor." "Jin-Woo Han is Senior Scientist at NASA's Ames Research Center in California's Silicon Valley. Along with colleagues Meyya Meyyappan, Myeong-Lok Seol and Jungsik Kim, he has designed a nanoscale complementary vacuum field emission transistor (VFET). A vacuum field emission transistor (VFET), also known as nanoscale vacuum channel transistor, is a device with no semiconductor channel. Instead, it has an empty gap between the source and drain terminals. Electrons tunnel through this empty space. Vacuum diodes and triodes have long been known and used in numerous applications. Recently, researchers have combined the best of vacuum physics and modern integrated circuit manufacturing to produce VFETs on wafer scale with extremely small dimensions..."

Please Thank RF Superstore for Their Continued Support

RF Superstore launched in 2017, marking the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and microwave Industry. Pasternack fundamentally changed the way RF components were sold. Partner Jason Wright manages day-to-day operations, while working closely with Mr. Pasternack to develop RF Superstore into a world class RF and microwave component supplier. RF coaxial connectors & adapters, coaxial cable & cable assemblies, surge protectors, attenuators. Items added daily. Free shipping on orders over $25. We're leading the way again!

Sunday 27

Filter Theme Crossword Puzzle for December 27th

This December 27th crossword puzzle has many words and clues related to Filters (indicated with an asterisk *). For the sake of avid cruciverbalists amongst us, each week I create a new crossword puzzle that has a theme related to engineering, mathematics, chemistry, physics, and other technical words. As always, this one contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

Friday 25

HPE Invents 1st Memristor Laser

"Researchers at Hewlett Packard Labs, where the first practical memristor was created, have invented a new variation on the device - a memristor laser. It's a laser that can have its wavelength electronically shifted and, uniquely, hold that adjustment even if the power is turned off. At the IEEE International Electron Device Meeting the researchers suggest that, in addition to simplifying photonic transceivers for data transmission between processors, the new devices could form the components of superefficient brain-inspired photonic circuits. Different colors of light can travel simultaneously through optical fibers and other waveguides so photonic transceivers that can adjust their wavelength..."

DARPA Demonstrates, Transitions Advanced RF Networking Program

"A DARPA network technology program recently concluded field tests demonstrating novel software that bridges multiple disparate radio networks to enable communication between incompatible tactical radio data links - even in the presence of hostile jamming. The technology is transitioning to Naval Air Systems Command (NAVAIR) and the Marine Corps, which plans to put the software on a software reprogrammable multi-channel radio platform for use on aircraft and ground vehicles. Started in 2016, the Dynamic Network Adaptation for Mission Optimization program, or DyNAMO, has developed technologies that enable automated, real-time dynamic configuration of tactical networks to ensure that heterogeneous radio nodes..."

Checkers by Radio

Game playing with a remote opponent is routine these days thanks to the Internet, but a couple decades ago it was not quite so easy. A checkers or chess match via telephone, snail mail (the only kind of mail at the time), or even fax machine were the venues available to the common man, but Hams had another means - radio! Using either Morse code or voice (aka phone) and a playing board set up like the one shown in this article, two players could easily match wits anywhere in the world where signals could be exchanged. Evidently the participants could get so wrapped up in the game that they risked forgetting to broadcast their call signs at the legally required interval (every 10 minutes), so author Utterback provides a friendly admonition at the end...

Thanks to Reactel for Their Long-Time Support!

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

Thursday 24

Merry Christmas from RF Cafe!

Here are a few of my favorite Christmas music videos. They include an eclectic mix of Cloverton, the Trans-Siberian Orchestra, an unlikely duet sung by Bing Crosby and David Bowie, and Casting Crowns. Watching the instruments being played really enhances the effect of the song. I used to have the videos embedded in this page for easy viewing all in one place, but each year on some of them I have to go find new hosting location because the previous year's had been removed. This time I am just linking to the YouTube (and other) web pages. The U.S. Air Force Band performance at the Smithsonian Air and Space Museum is my newest addition for 2020...

February 1947 Radio-Craft Electronics-Themed Comics

Some of the best electronics-themed comics appearing in these vintage magazines are the "Radio Term Illustrated" type - IMHO, anyway. Most of them are ideas suggested by readers, then illustrators like Frank Beaven created the visuals. The comic on page 79 is pretty self-explanatory, but the page 66 pun might need some explanation to those unfamiliar with vacuum tube circuits. The "B" battery is a term created by Mr. Lee de Forest as a designation for the second battery required for the plate bias (the "B") of his Audio tube. Typical voltages were 45 volts, 67½ volts, and 90 volts. If that doesn't completely clear up the pun, then you also need to know that an alternative definition of battery which is a military artillery installation...

Radar Chips Bring 4D Imaging to ADAS

"Radar has become a mainstay for advanced driver-assistance systems (ADAS), and the single radar used for advanced cruise control is being augmented by half a dozen or more radar systems. By 2023, cars will have a mix of radar, lidar, and camera-based systems providing significantly more situational awareness to the driver, in addition to being used by self-driving car solutions. By 2023, more than half of new vehicles will incorporate radar as well as other long-range sensor systems. NXP Semiconductors has been a major supplier of radar technology for automotive applications. Its latest offering starts off with the TEF82xx radar transceiver. A single chip can address a number of applications supporting 76- to 81-GHz bands with usable bandwidths up to 4 GHz. A 6-bit phase rotator enables advanced modulation MIMO and beam-steering support..."

The Day Before Christmas

The December 1958 (my 1st Christmas) issue of Radio-Electronics magazine featured a clever take-off of the famous children's story "Twas the Night Before Christmas," by Clement Clarke Moore (originally titled A Visit from St. Nicholas). "The Day Before Christmas," by Jack Darr, might contain some terms not familiar to a more contemporary crowd. For instance, how many even know that "Gunsmoke" was a Prime Time television shown from the 1950's, and is not just a forbidden word in today's public schools (since it contains the word "gun")? How about an antenna on the roof, or a telephone with a "dial" on it? Most people don't even carry paper "pelf" around anymore. If you're under 30 years old and run across an unfamiliar word or phase, simply speak it into your smartphone and Siri (or some variant) will be glad to look it up for you ;-) ...

QST Christmas Covers

As our traditions are besieged by malcontents determined to denigrate, impugn, and ultimately erase memories of holidays and events that have meant so much to families and friends, I feel compelled to resist the movement by documenting parts of the past that will cause us to wax nostalgic over our cherished traditions. Intimidation and violence is part of the strategic calculus; we have seen it in spades in 2020, and 2021 promises to be even worse. The Cancel Culture might eventually win out with the complicity of government agents both elected and unelected, but I'm not going down without a fight. Here is a collection of twentieth century, December issue QST magazine covers with Christmas themes that will no doubt be familiar to many of you. Finding them was more difficult...

Many Thanks to Withwave for Continued Support!

Withwave 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 4-port vector network analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures for calibration and multicoax cable assemblies. Frequency ranges from DC through 110 GHz. Please contact Withwave today to see how they can help your project succeed.

Radio Training Association of America Advertisement

Whenever I see advertisements for electronics training courses, I think of the line in "Duel in the Snow, or, Red Ryder Nails the Cleveland Street Kid," where it mentions how during the Great Depression years the magazines were filled with ads "promising successful careers repairing radios." That story, which ultimately became the book and movie "A Christmas Story," was contained in Gene Shepherd's book In God We Trust: All Others Pay Cash. Jean Shepherd was a radio announcer and story teller who first read "A Christmas Story," on his WOR (New York City) show in 1970. You can listen to a 1974 broadcast in the YouTube video embedded below. This reading is slightly different than the one given to me by a guy who actually recorded it on tape...

Please Visit Electro-Photonics in Appreciation of Support

Electro-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. 

Wednesday 23

Radio-Electronics Monthly Review

Probably the biggest news in the March 1944 issue of Radio-Craft magazine's "Monthly Review" feature was the invention of an extremely sensitive particle mass analyzer by Dr. James Hillier, of Radio Corporation of America (RCA). Vladimir Zworykin, who you might recognize as a television pioneer, is in the photo with Dr. Hillier. A related technology, electron microscopy, was used to image viruses in the blood stream. The National Bureau of Standards, now called NIST, announced a new time standard broadcast signal consisting of a precise 2.5 MHz pulsed tone feature a missing pulse once per minute. This facilitated calibration of frequency and time standards. There is also an analog simulator built by Westinghouse for use in designing high voltage power transmission networks where up to 18 separate...

Google Loon Project Seeks FCC Approval for 70 to 90 GHz Tests

"Loon LLC, an Alphabet Inc. subsidiary, is working to bring HAPS-powered Internet access to unserved and underserved communities around the world. Loon has submitted its statement pursuant to the US Federal Communications Commission (FCC) in support of its application for an Experimental Radio Service License to conduct a market trial. Loon seeks authority to tap spectrum between 70 GHz and 90 GHz (E-band), from fixed base stations in Puerto Rico that will utilize High Altitude Platform Stations (HAPS) as relay transmission points to deliver broadband service to maritime vessels operating in line-of-sight..."

Notable Tech Quote: Carson's Consolation

"Nothing is ever a complete failure; it can always serve as a bad example." - Carson's Consolation. I tried to find out who this Carson guy is, but to no avail. It is probably not John Renshaw Carson, who developed the well-known amongst RF Cafe visitors bandwidth rule stating BW = 2·(Δf + f_m). The same quote is sometimes referred to as Carlson's Consolation. Regardless of its progenitor, the tenet holds true.

Thanks Again to Axiom Test Equipment for Support!

Axiom Test Equipment allows you to rent or buy test equipment, repair test equipment, or sell or trade test equipment. They are committed to providing superior customer service and high quality electronic test equipment. Axiom offers customers several practical, efficient, and cost effective solutions for their projects' TE needs and is committed to providing superior customer service and high quality electronic test equipment. For anyone seeking a way to offload surplus or obsolete equipment, they offer a trade-in program or they will buy the equipment from you. Some vintage items are available fully calibrated. Please check out Axiom Test Equipment today!

Radio Rocket / Rocket Radio

After seeing the Future Radio Rockets article I posted recently, website visitor and contributor Joseph Birsa (N3TTE) sent me a note about the vintage "Rocket Radio" toy that was around when he (and I) were kids. The CrystalRadio.net website has a great page devoted to the Rocket Radio, including a schematic and theory discussion. It used a single crystal - a 1N34 diode - for the detector and a simple LC tank circuit for tuning. An ear bud (as opposed to a speaker) provided the audio signal since being entirely passive, the signal power from the ether to the ear bud had to be provided entirely by the radio wave - which is pretty amazing when you think on it. Conspiratorialist tweak: If the EM wave can provide enough power (after detection) to stimulate your eardrum, can it also stimulate your brain directly as a radio wave? As is usual, you can probably get a vintage Radio Rocket on eBay if you're willing to pay the super high price most of these items are commanding these days.

Hallicrafters: Here's to a Good Old Fashioned Christmas

As was customary for U.S. businesses, Hallicrafters ran a Christmas advertisement in the January issue of magazines where they appeared. The January edition, as is common even now, is typically mailed in early December, getting it in the hands of readers in time for Christmas. This "Here's to a Good Old Fashioned Christmas" (which many state governors want to end beginning this year) message appeared in the January 1942 issue of QST magazine. Halli(gan) and (hand)crafters was founded in Chicago in 1932 by William J. Halligan. The company designed and manufactured radio equipment for hobby, commercial, and military applications and quickly became very popular amongst their users...

Many Thanks to Aegis Power Systems for Their Continued Support!

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

Tuesday 22

Guided TV Bomb

In spite of the benefit afforded by the well-respected accuracy of the Norden bomb sight, striking a target from altitudes of up to thirty thousand feet is literally a hit-or-miss prospect. At that distance, a small angular error in the sighting mechanism can equate to hundreds of feet at ground level. A one degree field of view from 30,000 feet covers a ±262 foot area, which is good enough for dropping a huge barrage of bombs on a munitions factory spread out over a few hundred acres. However, the higher the aircraft flies, the more variables enter the calculation on the bomb's earthward trajectory. Wind shears and aircraft altitude, ground speed, and direction needed to be accounted for, all of which was calculated automatically by the Norden's analog computer...

Material System Converts and Generates THz Waves

"On the electromagnetic spectrum, terahertz light is located between infrared radiation and microwaves. It holds enormous potential for tomorrow's technologies: Among other things, it might succeed 5G by enabling extremely fast mobile communications connections and wireless networks. The bottleneck in the transition from gigahertz to terahertz frequencies has been caused by insufficiently efficient sources and converters. A German-Spanish research team with the participation of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has now developed a material system to generate terahertz pulses much more effectively than before. It is based on graphene..."

2020: The Year that Was...

"anatech-electronics-december-newsletter-12-22-2020.htm" target="_top"> Sam Benzacar of Anatech Electronics, an RF and microwave filter company, has published his December newsletter that features his short op-ed titled "2020: The Year that Was... ," in which Sam assess how he well did in predicting various key industry trends at the end of last year. You can read his piece to see how he scored, but I do want to note a specific point. One of Sam's predictions pertained to the availability of broadband service in rural areas. The Wuhan Flu epidemic that caused most schools to implement a remote classroom environment exposed how deficient the system still is, even though we thought the issue had been pretty much resolved (goodness knows we've spent enough tax money to address it). Also included in the newsletter are a few pertinent industry headlines. Stand by for Sam's end-of-year predictions for 2021...

Thanks Again to Triad RF Systems for Long-Time Support

Triad RF Systems designs and manufactures RF power amplifiers and systems. Triad RF Systems comprises three partners (hence 'Triad') with over 40 years of accumulated knowledge of what is required to design, manufacture, market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA, bi-directional, and frequency translating amplifiers are available, in formats including tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology partner than a vendor for our line-of-sight communications product line." Please check to see how they can help your project.

The Day Before Christmas

I saved this poem from the December 1935 edition of the ARRL's QST magazine for now since it might be the last day of work for the year for many people. "The Day Before Christmas" was penned by radio amateur Robert H. Votaw after the manner of the classic "The Night Before Christmas." It is rare to see such a poem printed in a technical magazine these days, but it was fairly common back in the day. To wit: "Ravin" (1942), "Power Supply" (1944), "Pre-Radio" (1944), "A Radioman's Nightmare" (1945). If you happen to be related to or knew Mr. Votaw, please send me a note...

The Merry Christmas Equation

An RF Cafe visitor sent this equation to me a few years ago. It can be found all over the Internet (including here), but I cannot determine a definite origin. Mathematicians claim that math can explain everything in the universe, which is not quite true. It can't for example, explain why my next-door neighbor is a junk hoarder. This Christmas equation does not appear to begin with a particular application; it looks like something from a set of textbook end-of-chapter problems. Even if you don't celebrate Christmas, it provides a secondary benefit by demonstrating rules for the manipulation of logarithms and exponents along with basic algebraic rearrangements of terms.

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

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

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. Some quoted items have been shortened to save space. About RF Cafe.

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- Christmas-themed items