Homepage Archive - April 2020 (page 1)

Friday 10

"Madman" Muntz TVs, Cars & Zany Commercials

RF Cafe visitor Mike M. reminded me of "Madman Muntz," who was a widely known television commercial personality on the West Coast from the 1950s through the 1970s. Earl William "Madman" Muntz's zany live and animated commercials were used highly successfully in selling cars, including one he himself designed and manufactured called the Muntz Jet. Along with being a master salesman, Madman Muntz was also a self-taught electronics engineer of sorts. He is credited with developing the first 4-track stereo tape deck for cars, which was a precursor to the 8-track tape deck. What Mike mentioned specifically was the line of Muntz television sets. Not satisfied to merely manufacture TV sets, Muntz created an entire service shop and fleet of mobile television trucks. It was kind of an early version of the Nerd Herd. Based on the Madman's trademark method of minimizing the number of components used in his products...

RF Cascade Workbook 2018

RF Cascade Workbook 2018 is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. Chances are you have never used a spreadsheet quite like this. It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed. An intro video takes you through the main features...

Connecticut Telephone & Electric Division Advertisement

This ad for Connecticut Telephone & Electric Division appeared in the January 1945 edition of Radio News. The company, as the name suggests, manufactured communications equipment, but as the name does not necessarily suggest, it also made radios and accessories. The Radio Museum website has a collection of photos and specifications about some of the equipment, such as the Vacuum Tube Detector Set Type DT-3 and Sodion DR6 single-tube receiver. Connecticut Telephone & Electric Division began operations at the dawn of the wireless communications age and produced a lot of materiel for the armed forces in World War II. Some of the vintage Connecticut Telephone & Electric Division components appear occasionally on eBay.

USSF Space Fence Radar Now Operational

"A radar system known as Space Fence, which can track material in space as small as 10 cm, is fully operational, the U.S. Space Force announced. Using enhanced S-band radar, the Space Fence improves on previous capabilities of the Space Surveillance Network in tracking objects such as commercial and military satellites, depleted rocket boosters and space debris in low, medium, and geosynchronous Earth orbit regimes, Space Force officials said on Friday. The SSN has tracked 26,000 objects already accounted for in space, and the new system is expected to vastly increase that figure, essentially offering a catalog and location of every object in space. 'Space Fence is revolutionizing the way we view space by providing timely, precise orbital data on objects that threaten both manned and unmanned military and commercial space assets..."

Mini-Circuits and Modelithics Provide 14 New Amplifier Models

"Modelithics-Mini-Circuits-14-Amplifier-Models-4-10-2020.htm" Modelithics, Inc. and Mini-Circuits have expanded their partnership by developing new high-accuracy simulation models for several packaged "Modelithics-Mini-Circuits-14-Amplifier-Models-4-10-2020.htm" Mini-Circuits amplifiers. In total, 14 new substrate-selectable amplifier models have been developed. These data-based models were extracted by performing broadband S-parameter and noise-parameter measurements with a Keysight PNA-X vector network analyzer (VNA), as part of a Maury Microwave ultra-fast noise parameter measurement setup. Modelithics now offers over 68 models, representing over 130 individual Mini-Circuits components, that include amplifiers, filters and splitters, among others. All the new amplifier models are currently available for FREE for use within Keysight Technologies' PathWave Advanced Design System (ADS)...

Reactel: RF & Microwave Filters of All Types

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 9

Helen Staniland Quam Elected President of the AEPEM

Female RF Cafe visitors might be interested to learn from this "Within the Industry" column which appeared in the 1958 Radio & TV News magazine of Helen Staniland Quam being elected president of the Association of Electronic Parts & Equipment Manufacturers, Inc. She was the first woman to head a major trade group in the electronics industry. A couple pages away in the same issue carried a half-page advertisement for her Quam-Nichols Company. The company was a primary supplier of audio speakers for radio and television original equipment manufacturers (OEMs) and for commercial loudspeaker installations. Sadly, other than a mention or two in vintage electronics magazines, there is not much about her accomplishments to be found on the Web.

Quam-Nichols Company Speakers

This advertisement for the Quam-Nichols Company's famous line of speakers appeared in the the June 1958 issue of Radio & TV News magazine, just a couple pages after a "Within the Industry" column announcing Helen Staniland Quam having been elected president of the Association of Electronic Parts & Equipment Manufacturers, Inc. The company, born in Chicago, Illinois, is still in business, but now going by the name Quam Speakers. From their website: "Commercial loudspeaker products have been our sole focus since 1930. This means nearly 90 years of real world learning, testing, refining, re-inventing, adapting - not just our products but also our way of working with our customers. We understand that commercial loudspeakers are often the last thing on your mind, but it's the first thing your clients hear..."

Gyroscope Design Help Autonomous Cars, Robots Map World

"It's 10,000 times more accurate than the gyros in your cell phone, but costs just $50. As useful as GPS is, it's not a system that we can rely on all the time. There are many situations in which GPS might not be available, such as when you're inside a building, driving through a tunnel, on a battlefield, in a mine, underwater, or in space. Systems that need to track location, like your cell phone, an autonomous car, or a submarine, often use what are called Inertial Measurement Units (a combination of accelerometers and gyroscopes) to estimate position through dead reckoning by tracking changes in acceleration and rotation. The accuracy of these location estimates depends on how accurate the sensors in those IMUs are. Unfortunately, gyroscopes that can do a good job of tracking rotation..."

Webinar: Facts and Fallacies in RFPA Waveform Engineering

"Cadence-AWR-Webinar-Facts-Fallacies-RFPA-Waveform-Engineering-4-8-2020.htm" Cadence| AWR will host a free webinar on April 28 at 12:00 pm EDT  titled "Facts and Fallacies in RFPA Waveform Engineering," presented by RF power amplifier (RFPA) expert Dr. Steve Cripps. What: Waveform engineering has been an important concept in RF power amplifier (RFPA) design, resulting in the definition of important new PA modes. The concept can, however, be taken too far. Sponsored by Cadence, this "Facts and Fallacies in RFPA Waveform Engineering" free webinar is presented by PA expert Dr. Steve Cripps of Cardiff University, who will illustrate some common misconceptions surrounding waveform realization using various design examples, including both switched and analog cases...

Satellite Electronics

Echo 1 was put into orbit on August 12, 1960. This article was written 2½ years earlier in 1958 by Radio-Electronics editor Hugo Gernsback. A technology visionary and prolific inventor and writer, Mr. Gernsback astutely outlined the vast number of advantages that had already been and would in the future be afforded the science community by virtue of a satellite's perspective from space. Two of the Soviet Union's Sputnik satellites had revealed the surprisingly irregular shape and gravitational influence of the Earth, information about the upper atmosphere, and aspects of space environment effects on radio communications. America was scrambling to catch up. Gernsback and others postulated the configuration of active relay transceivers powered by solar cells and storage batteries, satellite-based television and radio...

"Stayin' Inside" Coronavirus Bee Gees Parody

In keeping with the effort to spread the news about how to protect yourself from the Wuhan Flu until an inoculation can be developed, here is the "Stayin' Alive" YouTube sensation produced from disparate locations by some stay-at-homers in Sweden. BTW, in case your weren't around during the 1970s disco era, the Bee Gees are the (B)rothers (G)ibb. If you find yourself quarantined (literally or effectively), then you can relate to "My Corona Home," a parody of the Beach Boys' "Kokomo" song.

Electro-Photonics Offering RF & Microwave Products

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 8

Antenna Principles: Directive Arrays w/Metal-Screen Reflectors

Part VI of the multi-month series of articles on antenna principles which appeared in Radio-Craft magazine covers directive arrays with metal-screen reflectors. Metal-screen, wire, and mesh reflectors are discussed as reflector surfaces for broadside array, the collinear array, and billboard array collections of dipole elements. An interesting statement by author Jordan McQuay is, "It is more practical and efficient to use a reflector screen [as opposed to reflector dipole elements], particularly if there are a large number of dipoles. Such a non-resonant reflector is easier arid cheaper to construct, and provides a better broad-band response than a resonant reflector." I don't know enough about antenna deign to determine whether with modern methods of simulation and construction, if that still holds...

Top 20 Engineering Schools by Salary

The Design News website published their list of engineering schools with alumni that earn the highest salaries. As usual, all the familiar names appear, but with some shuffling of positions. For a reason I still do not understand - and I'm not knocking it - Harvey Mudd College leads the pack with an entry level salary of $90,700 and a mid-career salary and $161,800. Stanford was #2 and MIT #3. For reasons I do understand, military academies consistently rank highly (USNA #4, USMMA #10, USCGA #19). Says, the article: "As part of Engineering Week, we're presenting the 2020 report from PayScale (2019 report) shows which schools are turning out the highest paid grads with a bachelor's or graduate degree. Two years ago we posted the results of PayScale's study that only included grads with bachelor's degrees. The difference in the lists is surprising. PayScale defines engineering schools as those public or private institutions that grant more than 50 percent of their undergraduate degrees in math, sciences, computer science, engineering, or engineering technology majors..."

After Class - Using Load Lines

Use of a load line chart is a fast way of selecting the bias (operating) point and operational range for nonlinear devices. Notice that I didn't specifically say for transistors because this particular article deals with load lines for vacuum tubes. Almost nobody has any need for tube load line charts anymore, but the skill needed to interpret load lines for transistors is fundamentally the same as for tubes. Substitute Vce (collector-to-emitter voltage) for Plate Volts and Ic (collector current) for Plate Milliamperes and you have equivalence. Popular Electronics magazine ran this "After Class" tutorial series covering a broad variety of topics for many years. There is a short quiz at the end...

Spin Capacitor Cuts Heat and Power

And now, the cousin of the Flux Capacitor --- the Spin Capacitor! "In what is claimed to be a world first, physicists have developed a so-called spin capacitor that could herald new electronics that require less power and generate less heat. The advance by scientists at Leeds University generates and holds the spin state of electrons for a number of hours compared to previous efforts that held the spin state for a fraction of a second. Their results are published in Science Advances. A conventional capacitor holds energy in the form of electric charge and the development from Leeds does this also whilst storing the spin state of a group of electrons. According to the university, this could lead to a storage device measuring one square inch that could store 100 terabytes of data..."

Coronavirus Patent - Who Knew?

Let me start by saying this is NOT the COVID-19 form of coronavirus. It is patent US10130701B2 issued to a UK research entity. A CNIPA (China National Intelligence Property Administration) website search does not show any coronavirus patents - maybe the Wuhan Institute of Virology application is still pending. A search on the USPTO website for "coronavirus" (ttl) turns up 75 results. I'm not sure which makes me more uncomfortable - a communist country's patent office that shows no coronavirus patents or a representative republic country's patent office that shows scores of them, with 5 having China (cn) as the assignee country (acn).

MPDevice: RF & Microwave Circulators & Isolators

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 7

400 Million U.S. Radios?

Famous quotation books are full of statements made by people - many of them "experts" - throughout history which have proven to be hilariously wrong, and unfortunately some have been tragically wrong. Thomas Watson, president of IBM, in 1943 famously predicted on digital computers, "I think there is a world market for maybe five computers." In 1946, 20th Century Fox's Darryl Zanuck declared, "Television won't be able to hold on to any market it captures after the first six months. People will soon get tired of staring at a plywood box every night." Virtually on the eve of the PC revolution (1977), DEC founder Ken Olsen, "There is no reason anyone would want a computer in their home." British Prime Minister Neville Chamberlain assured his countrymen regarding Adolph Hitler's assurance of nonaggression, "I have returned from Germany with peace for our time". In 1947 when Radio-Craft magazine founder and editor wrote this article telling of the many in-the-know types who were predicting a grave future for commercial broadcast radio once television became a common fixture in households...

Promote Your Company on RF Cafe for as Little as $40/mo.

RF Cafe typically receives 8,000-15,000 website visits each weekday and about half that on weekends. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 13,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. If you need your company news to be seen, RF Cafe is the place to be. Advertising begins at $40/month.

Low-Loss Coaxial Cable

When it comes to low loss transmission media, it's hard to beat waveguide and open wire. Open wire can exhibit less a couple tenths of a decibel per hundred feet at low frequencies, but it is very susceptible to perturbations from nearby objects, wind and moisture. Waveguide exhibits a few tenths of a decibel per 100 feet at very high frequencies, but it is expensive and difficult to work with. In the middle is coaxial cable, which for a good quality product of appropriate size, you can get very low attenuation. As with most things, you get what you pay for in coax cable. I once used really expensive Andrew (now Commscope) Heliax coax cable on an S-band radar (2.8 GHz) system that had only a little more than 1 dB/100 ft, which was necessary from a receiver noise figure requirement rather than for transmitter power efficiency. This article from QST covers some of the basics of low loss cable...

ICNIRP Publishes New RF Electromagnetic Exposure Guidelines up to 300 GHz

"The International Commission on Non-Ionizing Radiation Protection (ICNIRP) has released new guidelines for the protection of humans exposed to radio frequency electromagnetic fields. The guidelines cover the upcoming 5G technologies, as well as AM and DAB radio, WiFi, Bluetooth, and the currently used 3G/4G mobile phones. ICNIRP Chairman, Dr. Eric van Rongen, said the new electromagnetic field guidelines have taken seven years to develop and are more appropriate than the 1998 guidelines for the higher frequencies that will be used for 5G in the future. He added that they know parts of the community are concerned about the safety of 5G and they hope the updated guidelines will help put people at ease. The guidelines have been developed after a thorough review of all relevant scientific literature, scientific workshops, and an extensive public consultation process. They provide protection against all scientifically substantiated adverse health effects due to EMF exposure in the 100 kHz to 300 GHz range..."

Make Sense of Antenna Design and Matching Networks

Mr. Asem Elshimi has an article entitled "Make Sense of Antenna Design and Matching Networks" on the EDN website. He introduces the basics of EM radiation and ideal antenna formats, then discusses acceptable compromises based on the application. "When it comes to actual antennas in the real world, much of our knowledge is empirical. We know very broadly theories that explain how a point charge radiates (Maxwell's equations), the need for matching (microwave theory), and how dipole antennas drawn on paper radiate the way they do, but these laws are nearly useless in solving the real-world problem of antenna design. By sharing my intuition on how wireless electronics work on a physical level, I hope to be useful in shaping a broad understanding of antenna design and matching networks and underscore the value of best practices and hard-earned wisdom..." (note Fig. 1 antenna drawings appear to be mine)

Broadband Engineers Threatened over 5G Coronavirus Conspiracies

"EE suspects telephone mast engulfed by fire in Birmingham was an arson attack as celebrities claim Covid-19 caused by new network ('ØG' video). Ofcom has warned broadcasters to refrain from spreading rumors that 5G is linked to coronavirus. Telecoms engineers are facing verbal and physical threats during the lockdown, as baseless conspiracy theories linking coronavirus to the rollout of 5G technology spread by celebrities such as Amanda Holden prompt members of the public to abuse those maintaining vital mobile phone and broadband networks. Facebook has removed one anti-5G group in which users were being encouraged to supply footage of them destroying mobile phone equipment, with some contributors..."

Exodus Advanced Communications: RF & Microwave Power Amplifiers

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.

Monday 6

Radio Data Sheet 345 Admiral Model 6RT44-7B1

Whenever I post any of these Radio Data Sheets from vintage electronics magazines, I attempt to find photos of actual units. Drawings are good, but actually seeing a for-real example is the best option. This Admiral Model 6RT44-7B1 phonograph appears on the Radio Attic's Archive website. As mentioned previously, electronics service shops relied heavily on these Radio Data Sheets that were printed in monthly magazines like Radio-Craft, Radio News, and Radio & Television News. The alternative was purchasing service documentation from the manufacturer (often only available to factory-authorized shops), from Sam's Photofacts, or some other third-party supplier. Of course experience and intuitiveness could substitute for documentation, but as many episodes of John T. Frye's series of "Mac's Radio Service Shop" illustrates, quirky variations in circuits...

Graphene Transistor Amplifier for THz & Light

"A new type of graphene amplifier could offer researchers a unique way to access the electromagnetic spectrum. Engineers from Loughborough University have designed an optical transistor out of graphene and a high-temperature superconductor that can amplify terahertz frequencies, and could unlock a whole new field of potential technologies. Terahertz waves (THz) have long fascinated scientists, but unfortunately, their use has been limited by their weak signals. Without an added boost of power, the wavelengths have been too weak for researchers to harness their potential power - until now, that is. The amplifier is deceptively simple, made up of two layers of graphene and the superconductor..."

Probability Stick Broken into 3 Pieces Can Form a Triangle?

"There's a tricky question asked at Google and Amazon interviews that is bound to stump you. However, worry not as YouTuber Zach Star is here with the solution in this fun video. The question goes like this: let's say you have a stick that you will randomly cut in three pieces. What are the odds that the three pieces created can form a triangle? If the three pieces are about equal in size, you can make a triangle. If, however, you have two much smaller pieces, you can not. It should also be known that for a triangle to be made, the two shortest lengths combined need to be bigger than the third. How does that relate to our question? Well, you have to watch the video for that..."

Z-Comm SMV0912B-LF 865 to 960 MHz VCO

"Z-Comm-SMV0912B-LF-VCO-4-3-2020.htm" Z-Communications, Inc., announces a new RoHS compliant VCO (Voltage-Controlled Oscillator) model "Z-Comm-SMV0912B-LF-VCO-4-3-2020.htm "SMV0912B-LF . The SMV0912B-LF operates from 865 to 960 MHz within a tuning voltage range of 0 to 2.5 Vdc. This low cost VCO features very clean spectral purity performance of -100 dBc/Hz @10 kHz offset and covers the frequency range with an average sensitivity of 80 MHz/V. The SMV0912B-LF is designed to deliver 3±3 dBm of output power into a 50 ohms load while operating over the industrial temperature range of -40 to 85°C. This high performance VCO is further enhanced by saving precious energy. It consumes a mere 6 mA of current while operating off a 3.0 Vdc supply. The SMV0912B-LF features a typical 2nd harmonic suppression of -10 dBc...

Science & Math Ignorance in the Media

Question: According to the legend on this graphic, how many confirmed cases of coronavirus do the gray-colored areas have (answer below)? Look at this "Countries with Confirmed Cases of Coronavirus" map used in an MSN.com news story. According to graphic creator Tara, it was provided by the World Health Organization. This is an example of why the news media should not be unquestioningly believed when presenting data. Its reporters are for the most part very scientifically and mathematically ignorant (and some are plain stupid). They do not know how to assimilate and present numerical information, while pompously demanding that everyone listen to the scientists. Answer: Exactly 100. Do you understand why?

Withwave: RF & Microwave Components

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.

Sunday 5

Engineering & Science Crossword Puzzle for April 5

Working crossword puzzles can be contagious. This April 5, 2020, tech-themed crossword puzzle may even go viral. It contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc., which I have personally built over nearly two decades. That includes the cause for our planet's current dilemma. Many new words and company names have been added that had not even been created when I started in the year 2002. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure village in the Andes mountains. You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which, if you don't already know, might surprise you...

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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