Homepage Archive - December 2020 (page 3)

Monday 21

Madame Curie and Electronics

Right on time for the anniversary of Pierre and Marie Curie's 1989 discovery of the radioactive element radium is this article which appeared in a 1944 issue of Radio-Craft magazine. Editor Hugo Gernsback comments on the recently released (1943) film titled "Madame Curie*," starring Greer Garson as Marie Curie and Walter Pidgeon as Pierre, criticizing it for not delving more deeply into the technical aspects of radium. Chief among the objections was the omission of information about how radiation treatment had been shown to cure some forms of cancer. Indeed, he cited his own experience with a "growth" on his hand that was successfully treated at a "radium hospital" where the doctor applied a bulb of radium to the tissue for a mere five minutes. It disappeared in less than two weeks. Beyond that would be radium's usefulness in generating electricity, creating wonderful visual effects created by its elemental decay using a spinthariscope...

Replacing Multiple RF Receivers with Just One Using Channelization

"From the early days of analog radio receivers to the superheterodyne channelized receivers of today, many things have changed. Today, different technologies are in use and their capabilities have grown immensely. This article will give you a brief overview of the development of radio receivers. Furthermore, it will show how channelization has made it possible to use one radio receiver to listen to many different radio stations simultaneously. In modern telecommunications, a point-to-point communication medium can be shared among multiple transmitters in various ways; for example, many different telephone calls can be transferred simultaneously via the same wire. In this case, each telephone conversation can be considered as a separate channel on this medium. Another example is traditional TV or radio stations that are transmitted..."

Please Thank Lotus Communication Systems for Their Support!

Lotus Communication Systems began in 2009, setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex Country, Massachusetts. Lotus is committed to highest quality and innovative products. Each RF/microwave module meets exceedingly high standards of quality, performance and excellent value, and are 100% MADE IN USA. Lotus' RF/microwave products cover frequency band up to 67 GHz. Lotus also offers an COTS shield enclosures for RF/microwave prototyping and production. All products are custom designed. We will find a solution and save your time and cost. Lotus has multiple 4 axis CNC machines and LPKF circuit plotters.

IEEE's 2018 "The Art of Failure Analysis"

Since 2008, IEEE's International Symposium on the Physical and Failure Analysis of Integrated Circuits (IFPA) has on occasion held an "Art of Failure Analysis" photo contest. Familiar shapes and patterns occur regularly in nature at the macro level that can be seen and recognized by almost anyone; e.g., the Nautilus spiral, the Fibonacci series in plant life, and fractal structures. It takes a high power optical microscope or even a scanning electron microscope (SEM) to see those sights in the realm of the very small. Sometimes, though, the images are downright bazaar and look eerily familiar...

Future Radio Rockets

We don't hear much - if any - talk these days about a certain weapon type being a "peace maker," "game changer," or a "stale mate proposition." That is because most nations, or for that matter terrorist groups, have access to some ferocious weapons. The world has operated for a long time on the Mutually Assured Destruction (MAD) principle, where skirmishes have been fairly local. Many conspiratorialists as well as arguably rational people believe the real game at hand is Mutually Assured Financial Destruction (no clever acronym for that one), where world financial powers cooperatively trade off monetary wins and losses via what was termed by President Eisenhower the Military-Industrial Complex. You don't need to be one who wears a tinfoil hat or keeps your savings buried in a jar in the back yard to suspect at least some form of malfeasance is going on at the expense of we the little people...

Many Thanks to Berkeley Nucleonics for Continued Support!

Berkeley Nucleonics Corporation (BNC) is a leading manufacturer of precision electronic instrumentation for test, measurement, and nuclear research. Founded in 1963, BNC initially developed custom pulse generators. We became known for meeting the most stringent requirements for high precision and stability, and for producing instruments of unsurpassed reliability and performance. We continue to maintain a leadership position as a developer of custom pulse, signal, light, and function generators. Our designs incorporate the latest innovations in software and hardware engineering, surface mount production, and automated testing procedures.

Sunday 20

RF Cafe Christmas Theme Crossword Puzzle

Just in time for Christmas - a yuletide crossword puzzle for you to work in the last moments of work while waiting for the boss to give the order to leave early for the lone holiday weekend. 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. The clues with asterisks (*) are particular to this December 20th Christmas-themed crossword puzzle. As always, it 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...

Friday 18

TV Station List Test Patterns & Logos

Anyone out there old enough to remember when you were a kid and managed to be able to stay up late enough, maybe on a Saturday night, to be able to watch the television station sign off the air at night? Here in the U.S., the custom was to announce the end of the programming day, play the National Anthem, and then put up the station logo while broadcasting a single tone. The tone and test patterns were actually used by TV technicians for calibrating instruments for use in servicing sets. In 1951 when this TV Station List appeared in Radio-Electronics magazine, black and white (B&W) was still the standard, so these images are what you would have seen then. I'm not quite that old (born in 1958), but I do recognize the stations we could receive at my parent's home in Mayo, Maryland. Being located between Washington, D.C., and Baltimore, a pretty good selection of both VHF and UHF...

In the Field with the Signal Corps

December 1942 was just a year into America's "official" involvement in World War II. Already, both wired and wireless communications had made major advances and were indisputably vital in both the logistical and strategic aspects of troop movement, supply chains, fighting battles, and evacuation of wounded personnel. It also played a large part in propaganda campaigns. This was all true for both Axis and Allied forces. Ham radio operators provided a huge boost to the Signal Corps because they came at least partially trained for the jobs. These dozen and a half photos from the field exhibit the state of the art at the time. Maybe you'll recognize a father, grandfather, or uncle in one of them. For that matter, you might even recognize a mother, grandmother, or aunt...

Terahertz Receiver for 6G Wireless Communications

"Future wireless networks of the 6th generation (6G) will consist of a multitude of small radio cells that need to be connected by broadband communication links. In this context, wireless transmission at THz frequencies represents a particularly attractive and flexible solution. Researchers at Karlsruhe Institute of Technology (KIT) have now developed a novel concept for low-cost terahertz receivers that consist of a single diode in combination with a dedicated signal processing technique. In a proof-of-concept experiment, the team demonstrated transmission at a data rate of 115 Gbit/s and a carrier frequency of 0.3 THz over a distance of 110 meters. The results are reported in Nature Photonics. 5G will be followed by 6G: The sixth generation of mobile communications promises even higher data rates..."

Many Thanks to Berkeley Nucleonics for Continued Support!

Berkeley Nucleonics Corporation (BNC) is a leading manufacturer of precision electronic instrumentation for test, measurement, and nuclear research. Founded in 1963, BNC initially developed custom pulse generators. We became known for meeting the most stringent requirements for high precision and stability, and for producing instruments of unsurpassed reliability and performance. We continue to maintain a leadership position as a developer of custom pulse, signal, light, and function generators. Our designs incorporate the latest innovations in software and hardware engineering, surface mount production, and automated testing procedures.

Conduct RF Phase & Temperature Stable Cables December 2020

"Conduct-RF-Phase-Temperature-Stable-Cables-12-8-2019.htm" target="_top"> ConductRF, a manufacturer of precision RF coaxial cable assemblies and connectors, announces the availability of "Conduct-RF-Phase-Temperature-Stable-Cables-12-8-2019.htm" target="_top"> Phase Stable / Temperature Stable solutions for both commercial and laboratory precision RF applications. 50 ppm phase accuracy with temperature phase matching capabilities, low loss and high power options, broad connector choices. Manufacturing capabilities include solutions built at our ITAR registered facility in Methuen, Massachusetts, 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...

Heathkit Electronics Training Courses - DC, AC & Semiconductors

Signing up for the U.S. Air Force's delayed enlistment program in May of 1978 gave me six months to come up to speed on basic electronics principles. Two years had passed since graduating from high school, and I had been working as an electrician in the interim. I had done three years of the electrical vocational program in high school so the fundamentals of electricity - Ohms law, Kirchhoff's law, AC & DC motors, industrial control circuits, commercial and residential wiring, etc. - were familiar, but electronics theory - transistors, tubes, diodes - had not been covered much. Knowing I would be attending many months of USAF electronics technical school, boning up on the topic seemed prudent. Having previously built a couple Heathkits, I decided to buy their electronics courses, along with the Heathkit ET-3100 Design Experimenter. The model shown in this 1982 Heathkit catalog...

Thanks to ISOTEC for Long-Time Support!

Since 1996, ISOTEC has designed, developed and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components and filters for wireless service providers including non-magnetic connectors for quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM RF connectors components such as power dividers and directional couplers. Off-the-shelf and customized products up to 40 GHz and our low-PIM products can meet -160 dBc with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and high-performance. Designs that are cost effective practical and repeatable.

Thursday 17

Radio Electronics Monthly Review

Imagine if engineers used physical mock-ups of semiconductor substrates with BB-sized metal balls representing electrons and holes to design the next whiz-bang transistor. You'd think they were insane. Seventy-three years ago, before powerful computers and software were available to simulate the physics, engineers were doing just that sort of thing to figure out how to design vacuum tubes. This "Monthly Review" feature in the December 1947 issue of Radio Craft magazine has a photo of one of the models. Hills and valleys in the base represented voltage potentials that influenced the trajectory of the balls. Pretty clever, really. Also reported was the death of world-famous physicist and originator of the quantum theory, Mr. Max Planck. He was 89 years old - not bad for the era...

Essentials of Expressing Measurement Uncertainty

I when I originally posted NIST Technical Note 1297, it had the name "Essentials of Expressing Measurement Uncertainty." Since that time, the NIST website changed its link to the updated version which now goes by the title of "Guidelines for Evaluating and Expressing the Uncertainty of NIST Measurement Results." It includes a lot of new data; in fact, it has been nearly totally re-written. This is a valuable reference for anyone who needs to understand the proper method for calculating measurement uncertainties. Preface to the 1994 Edition The previous edition, which was the first, of this National Institute of Standards and Technology (NIST) Technical Note (TN 1297) was initially published in January 1993...

Atom-Thin Transistor Uses Half Voltage of Common Semiconductors

"University at Buffalo researchers are reporting a new, two-dimensional transistor made of graphene and the compound molybdenum disulfide that could help usher in a new era of computing. As described in a paper accepted at the 2020 IEEE International Electron Devices Meeting, which is taking place virtually next week, the transistor requires half the voltage of current semiconductors. It also has a current density greater than similar transistors under development. This ability to operate with less voltage and handle more current is key to meet the demand for new power-hungry nanoelectronic devices, including quantum computers. 'New technologies are needed to extend the performance of electronic systems in terms of power, speed, and density..."

Lamps & Tubes Museum

If you like pictures of très cool-looking devices involving vacuum-filled (an oxymoron?) glass enclosures, i.e., lamps and tubes, then you will want to spend a few minutes perusing the personal collection of Giorgio Basile, of Nivelles, Belgium. Per the homepage of his Lamps & Tubes website: "My collection consists of more than 4,000 lamps and vacuum tubes. This is a wide area! In addition to well known incandescent lamps, radio tubes and cathode ray tubes, it includes, among others: arc lamps, light sources for the laboratory, transmitting tubes, camera tubes, flash lamps, microwave tubes, photocells, photomultipliers, radiation detectors, rectifiers, relays, thyratrons, vacuum gauges, X-ray tubes...

Heathkit / Zenith Z-100 Computer Series

If you had $4,000 to spend on a desktop computer today, your money would get you a top-end 8-core microprocessor with at least 32 GBytes of super-fast RAM, a couple TBytes of solid state hard drive space, and at least a 32" high definition screen monitor. It would be a top-of-the-line machine any serious gamer would envy. In 1982, the same cash would also get you a top-of-the-line computer, but it would have a 1-core processor, a whopping 768 KBytes of sub-MHz RAM, a 10 MByte hard disk drive, and a 12" monochrome display. That describes the IBM PC, Tandy's TRS-80, as well as the Zenith Z-100 PC shown here from the Heathkit 1982 Christmas catalog. If you were around back then...

Please Thank LadyBug Technologies for Their Support!

LadyBug Technologies was founded in 2004 by two microwave engineers with a passion for quality microwave test instrumentation. Our employees offer many years experience in the design and manufacture of the worlds best vector network analyzers, spectrum analyzers, power meters and associated components. The management team has additional experience in optical power testing, military radar and a variety of programming environments including LabVIEW, VEE and other languages often used in programmatic systems. Extensive experience in a broad spectrum of demanding measurement applications. You can be assured that our Power Sensors are designed, built, tested and calibrated without compromise.

Wednesday 16

The National QSO Page, 1938 Radio News

This "The National QSO Page" editorial from the December 1938 issue of Radio News magazine really took me by surprise. Evidently there was a rift with amateur radio operators over whether Radio News was attempting to overthrow the American Radio Relay League's (ARRL) dominance in the Ham realm. At the time, the ARRL had only been in existence for 24 years. There had been some previous criticism of the ARRL for not sufficiently (in Radio News' opinion) defending access to dedicated Ham spectrum and legal transmit power levels, and also for the ARRL counting among its membership anyone who subscribed to the organization's QST magazine. The former point is arguable, but the latter seems rather petty since likely the percentage of subscribers who were not ARRL members, too, is probably very small. Interestingly, Radio News accused the ARRL of being weak lobbyists in Washington...

Skyworks High-Power FEM for Automotive V2V and V2X Apps

"Skyworks-High-Power-FEM-Automotive-V2V-V2X-12-15-2020.htm" target="_top"> Skyworks is pleased to introduce the "Skyworks-High-Power-FEM-Automotive-V2V-V2X-12-15-2020.htm" target="_top"> SKYA21043, a highly-integrated, 5 GHz front-end module (FEM) incorporating a 5 GHz single-pole, double-throw (SPDT) transmit/receive (T/R) switch, a 5 GHz high-gain low-noise amplifier (LNA) with bypass, and a 5 GHz power amplifier (PA) intended for high-power 802.11p applications and systems. Qualified to AEC-Q104 (Grade 2), the SKYA21043 meets rugged reliability requirements for automotive applications including vehicle-to-vehicle (V2V) and vehicle-to-everything (V2X) covering smart antennas, compensators, and roadside units for automotive infrastructure, backhaul and cellular...

Thanks to PCBONLINE for Continued Support!

PCBONLINE supplies complex rigid and flex-rigid printed circuit boards (PCBs)，and one-stop production with maximum flexibility ranging from prototype sample to mass production. Rigid-flex, HDI, multilayer, IC-loadboard, LCP 5G optical module, ceramic, MCPCB. Materials include Rogers, Taconic, Arlon, Isola, Bergquist, Kapton, Panasonic, and more. After more than 15 years of continuous efforts, PCBONLINE constantly updates our equipment, improves our technology, and serves you with the highest quality. Cost and delivery quotations online without the need for multiple phone call and/or e-mails.

Copper Mountain Technologies 2-Port VNA Calibration Video

"Copper-Mountain-Technologies-2-Port-VNA-Calibration-Video-12-15-2020.htm" target="_top"> Copper Mountain Technologies (CMT), a leading developer of innovative RF test and measurement solutions for engineers all over the world, has produced a video demonstrating how to properly "Copper-Mountain-Technologies-2-Port-VNA-Calibration-Video-12-15-2020.htm" target="_top"> perform a 2-port calibration on a vector network analyzer (VNA). Virtually interact with CMT's software to complete a simulated calibration of a 2-port VNA. Note that the series of dashes and spaces along the video progress bar indicate where the action stops between steps to allow you time to replicate the action. You will need to click on the start arrow each time to resume action...

Amateur Radio Christmas Comics

Here are a couple good Christmas-themed comics from the January 1942 issue of the American Radio Relay League's (ARRL) monthly magazine, QST. Ironically, the "Old Year" Father Time with the sickle would not have been able to legally key that transmitter by the time readers had received this edition, because the U.S. government shut down all amateur radio transmissions (except a few specially sanctioned civil defense units) immediately after the Japanese attack on Pearl Harbor on December 7th of the previous year (see "War Comes"). Although, he would probably have received special dispensation from the FCC permitting him to send...

Ban on Hydroxychloroquine Rescinded by AMA

Experts and news outlets told Americans and people of the world not to use hydroxychloroquine (HCQ) as an off-label treatment for the Wuhan Flu, in spite of its being safely prescribed for decades. We were told by "experts" that no vaccine could possibly be developed in less than a year. Now, the American Medical Association (AMA) has changed its mind on HCQ and a vaccine is being distributed today. Politically motivated fake science has likely caused suffering and death for an untold number of people. Per Resolution 509 (p18), November 2020: "RESOLVED, That our American Medical Association rescind its statement calling for physicians to stop prescribing hydroxychloroquine and chloroquine until sufficient evidence becomes available to conclusively illustrate that the harm associated with use outweighs benefit early in the disease course..." Careful who you listen to - it could kill you.

Heathkit 19" Color Television Kit in Christmas 1982 Catalog

If you are shopping for a new television set and are willing to spend $500, you can get a fully assembled and ready to play Samsung 55" 4K UHD LED Smart TV with Alexa Built-in, or maybe a Vizio 50" 4K UHD LED Smart TV (UHD = 3,840px x 2,160px = 8,294,400 px^2). The same $500 in 1982 got you a 19" CRT with 525 horizontal scan lines (only 480-490 actually visible), but theoretically an infinite number of points across each line due to the analog nature of the signal. Come to think of it, an argument could be made that the old CRT displays had a higher resolution than the UHD modern digital TV (infinite versus 8.3 million, respectively). Ditto for the total number of color levels - infinite for analog versus 16.8 million for digital (8 bits per color = [28]^3). Fully assembled and ready to play 19" TVs could be bought in 1982 for about the same price, so the motivation for going to the trouble of building your own set was mostly pride and personal satisfaction...

Many Thanks to MPDevice for Continuing Support!

MPDevice (MPD) has become a trustworthy and reliable company in the global RF market as a manufacturer of passive RF devices. Included are attenuators and terminations, coaxial connectors, adapters, and cable assemblies, DC blocks, surge arrestors, power combiner / dividers, and directional couplers. The Korean Telecommunication market is now entering into the era of hyperconnected society. With continuous enhancement in R&D capabilities and quality control, MPD will continue in an effort to become the No. 1 technologically innovative company with a focus on the emerging 5G marketplace.

Tuesday 15

Sparks on Ice: Radio in the Arctic

The old adage about pioneers taking the arrows is true in many realms - not just the exploration and settling of the wild west. This story titled "Sparks on Ice" recounting the trials and tribulations of the troops who installed and debugged the first arctic directional beacons appeared in a 1945 issue of Flying Age magazine. "Sparks" (or "Sparky") was an endearing nickname given to early radio operators who used spark gap transmitters to send out their Morse code messages. It stuck around for many years after better transmitter systems were developed - although it is not very often heard today. The most interesting part of Mark Weaver's article is a discussion of the many atmospheric phenomena that affect radio waves of various wavelengths. A lot of smart people - enlisted, commissioned, and civilian - sacrificed mightily...

Heathkit Satellite Earth Station in Christmas 1982 Catalog

Remember the era when those big parabolic satellite television antennas (TVRO - television receive-only) began appearing on lawns all over the place? Some people painted them with camouflage to help disappear them from view, while others painted them to match the themes of their houses. Some got really obnoxious and painted targets or, even worse, big ugly eyeballs on the antennas. Most systems at the time operated on C-band, which explains, along with lower sensitivity receivers, the large size. The earliest antennas and receivers which came to market in the late 1970s coincident with the first TV broadcast satellites cost more than $10,000. By 1982 when this Heathkit Christmas catalog was printed, prices were down to just a few thousand dollars. Nowadays, a much smaller antenna operating at Ku-band is provided at no cost...

Transistor Design Disguises Key Computer Chip from Hackers

"A hacker can reproduce a circuit on a chip by discovering what key transistors are doing in a circuit - but not if the transistor 'type' is undetectable. Purdue University engineers have demonstrated a way to disguise which transistor is which by building them out of a sheet-like material called black phosphorus. This built-in security measure would prevent hackers from getting enough information about the circuit to reverse engineer it. The findings appear in a paper published Monday (Dec. 7) in Nature Electronics. Reverse engineering chips is a common practice - both for hackers and companies investigating intellectual property infringement. Researchers also are developing X-ray imaging techniques that wouldn't require actually touching a chip..."

U.S. Air Force Recruitment Advertisements in Saturday Evening Post

Although the original purpose of this note was just to announce a couple post-WWI era U.S. Air Force recruitment posters I found in The Saturday Evening Post magazines back in the late 1940s, some info I found regarding the newest USAF logo might also interest you. There is a plethora of old Air Force posters available for viewing on the Internet, but I haven't seen these two, which are particularly directed toward flight officers and the newfangled jet aircraft of the future. Operational jet-powered fighter craft did not appear until the final year of World War II, although Germany did have their Messerschmitt Me 262. Except maybe for the C-130, you probably won't see any propeller-driven aircraft in today's USAF promotional material. If you have any cause to display the USAF's new (relatively) wings symbol, be sure to consult this entire section of regulations governing the proper...

The Vital Role of Simulation for EMI and EMC Test Environments

COMSOL's Jiyoun Munn has an article posted on the Interference Technology website entitled, "The Vital Role of Simulation for Virtual EMI and EMC Test Environments." I first saw it reproduced in NASA's Tech Briefs. He begins: "Before deploying microwave and millimeter-wave devices and systems within 5G, the Internet of Things (IoT), and high-speed wireless communication, it is essential to predict their performance. This need has increased the demand for virtual test platforms through simulation software. High carrier and system bus frequencies are necessary for high-data-rate communication between multiple devices present in such systems. However, increased operational frequencies may induce undesirable and troublesome electromagnetic compatibility (EMC) and electromagnetic interference (EMI) issues, especially when communication is congested. Moreover, the impact from other physics is no longer negligible..."

Thanks to Exodus Advanced Communications for Their Support

Exodus Advanced Communications is a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide. Power amplifiers ranging from 10 kHz to 51 GHz with various output power levels and noise figure ranges, we fully support custom designs and manufacturing requirements for both small and large volume levels. decades of combined experience in the RF field for numerous applications including military jamming, communications, radar, EMI/EMC and various commercial projects with all designing and manufacturing of our HPA, MPA, and LNA products in-house.

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