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# Homepage Archive - May 2024 (page 3)

See Page 1 | 2 | 3 | 4 of the May 2024 homepage archives.

Tuesday the 21st

Scientific Development Corporation Minivac 601

In his spare time, when not developing world-changing concepts of information theory, Claude Shannon designed this Minivac 601 programmable computer for students and hobbyists. It had 6 bits of data storage, implemented with electromechanical relays. Its output consisted of six incandescent lamps. Marketed by Scientific Development Corporation, advertisements for it appeared in magazines like Popular Science in the early 1960s. \$85 in 1961 is the equivalent of around \$885 today per the BLS CPI calculator, which is about what high end smartphones cost today. Since this ad is pitching a computer, let us perform a few simple calculations. Inflation from 1961 through 2024 represents a factor of 10.4 in 63 years, an average of 0.165x per year. Four short years ago the equivalent price was \$731, representing a factor of 8.6 in 59 years, an average of 0.146x per year. Continuing, 0.165/yr ÷ 0.146/yr = 1.12, or a 12% increase in the last four years...

Student's Radio Physics Course - Series and Parallel Circuits

Not everyone who visits websites such as RF Cafe is a seasoned electronics veteran. While I and most likely you, too, can do series and parallel circuit analysis (and series/parallel for that matter, possibly using Fourier or La Place transforms for reactive AC circuits) in our sleep, many are recently getting into the wonderful world of electronics who are just coming of age or have suddenly at a later point in life developed a passion for the science. Accordingly, this article from a 1932 issue of Radio News magazine provides yet another tutorial on the fundamentals of series and parallel circuit analysis. Only resistors and basic Ohms law are covered. Don't let the vacuum tube schematic symbols deter you.

Will 6G Deliver Where Overhyped 5G Failed?

"5G communications technology has been overhyped but 6G may live up to the revolutionary promise that its predecessor did not, a British expert told a leading tech conference in China. Jiangzhou Wang, a professor at the University of Kent’s school of engineering, told a technology conference in Beijing on Friday that 5G had yet to result in a killer app. 'I am objectively disappointed with 5G,' Shanghai-based financial news site Yicai quoted Wang as saying at the Sohu Annual Sci-Tech Conference. 'In the 5G era, we have not seen a blockbuster application for ordinary consumers, nor has it been widely applied in vertical industries.' Future 6G technology might be revolutionary rather than incremental. '5G has been overhyped, as if it can do everything..."

LEGO Tech-Themed Sculptures

When LEGO blocks were first introduced in their current form in Denmark in the late1940s, founder Godfred Kirk Christiansen could not have imagined how wildly popular his "toy" would become with sculptors. That generations of kids would while away hours at a time building original and predesigned structures per printed instructions were his realized dream, Godfred would be in awe over how his creation has been applied from professional and amateur artists. By the way, LEGO is a contraction conceived of by Christiansen from the Danish phrase "leg godt," meaning "play well." The June 2012 issue of Scientific American magazine has an article titled "Fusion's Missing Pieces" on the current state of nuclear fusion, and with it is a photo of a cut-away view of a tokomak...

What Is It?

If subjects pertaining to electronics - particularly vacuum tubes - are like music to your ears, then this poem entitled "What Is It?," from the February 1943 edition of QST magazine, should suit you just fine. The rhyming words are supplied by author Frank Judd; you just need to supply the harmony. You might recognize paraphrasing of other familiar works such as Longfellow's "Paul Revere's Ride." Poems like this one were actually quite common back in the day. In fact if you look through the list of articles that I have posted from vintage QSTs, you will find about a dozen...

RF & Electronics Stencils for Visio

With more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks, and more. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...

Monday the 20th

Bell Telephone Labs: Time Domain Reflectometry

Maybe the term "time domain reflectometery" had not been coined when this Bell Telephone Laboratories (Bell Labs) advertisement appeared in a 1948 issue of Popular Science magazine. Or, maybe the creators figured Popular Science readers, while generally a more technically-oriented group, might not possess the depth of understanding needed to appreciate the phrase. At the time, use of coaxial cable transmission lines for carrying telephone calls was fairly new, although Bell began using some coaxial cable in 1927. A decade earlier, prior to great advances in high frequency communications during World War II, twisted pairs of solid conductors were sufficient to handle traffic. They did a good job, but each twisted pair carried only a single circuit operating at audio frequencies. That is why telephone cables were so large in diameter - they could be holding hundreds of twisted pairs. Coaxial cable signals can handle hundred or thousands of channels by modulating across a very wide bandwidth...

Wind Turbine Boneyard in Texas

You've seen photos of airplane boneyards in the desert where retired commercial and military planes are stored for use in cannibalization of replacement parts. A desert environment is ideal because corrosion from water is minimal. Did you know there are also wind turbine graveyards? One of the largest is located in Sweetwater, Texas. Most of what is stored there are the fiberglass and carbon fiber blades, cut into pieces for easier handling. Unlike the airplanes whose wing parts in time may serve a purpose, these wind turbine "wings" (that's what they are) will likely remain there forever. Some companies promise to recycle expired blades, but few ever do. EV battery pack boneyards probably also exist, but you'll never see a picture of one because political concerns will assure they are well hidden from public view (probably in a 3rd world country where child labor is used to process them).

Color Television Systems

It's probably a safe bet that most people, even at the dawn of color television, knew of the competition which occurred for the adoption of three different methods of implementation. Two of them - line-sequential by Color Television, Inc. (CTI), and dot-sequential by Radio Corporation of America (RCA) - were fully electronic while the third system by the Columbia Broadcast System (CBS) used a kludge of a spinning color wheel placed in front of a black and white display. The CBS field-sequential design used a synchronization component of the composite transmitted signal to position the correct color screen (red, yellow, or blue) in front of the screen as the electron gun scanned the CRT - analogous to how World War I airplane machine guns were synchronized with the engine to fire between propeller blades. Of course an out-of-synch scenario in the color wheel was not as serious as with the machine gun...

A Surprising Bit of Voting Law

As the general election approaches here in the U.S., more attention is being paid to voting legitimacy, particularly by non-citizens. This was very recently brought to light: 18 U.S. Code § 611 - Voting by aliens --- "(a) It shall be unlawful for any alien to vote in any election held solely or in part for the purpose of electing a candidate for the office of President, Vice President, ... Member of the Senate, Member of the House of Representatives, ... unless --- (c) Subsection (a) does not apply to an alien if --- (3) the alien reasonaly believed at the time of voting in violation of such subsection that he or she was a citizen of the United States." Undoubtedly the millions who have crossed into the U.S. have been instructed to claim such an exemption. Your vote can be nullified by an illegal alien with this. Undoubtedly the millions who have crossed into the U.S. have been instructed to claim such an exemption. Your vote can be nullified by an illegal alien with this.

Radio Control on the Citizens Band

Radio control (R/C) of a model doesn't get much simpler than the transmitter and receiver circuits shown in the schematics of Figure 2. Of course the cleanness of the transmitted signal and the selectivity of the receiver of that signal leaves a lot to be desired. In 1952 when this article appeared in Radio & Television News magazine, the airwaves weren't cluttered with wireless communications devices, but given that these radio systems were sharing the electromagnetic spectrum with Citizens Band (CB) radio, the chances of getting "shot down" from nearby operators was pretty high if you lived within a few miles of where CB'ers were communicating. More sophisticated R/C equipment was available from commercial manufacturers, but this system targeted the do-it-yourself types and those with limited hobby budgets. A lot of airplane models which consumed many hours and dollars of a flyer's resources met with their demise as the result of a stray signal blocking...

RF Cascade Workbook 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 (click here for screen capture). 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 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...

Friday the 17th

Rotary Engine Fires Like a Six-Shooter

Dig those crazy curved pistons, man. They are righteous! That was the sort of hip lingo just beginning to hit the scene in 1961 when this "Rotary Engine Fires Like a Six-Shooter" article appeared in Popular Science magazine. It was not a Wankel type rotary engine in that it still used pistons and connecting rods like a traditional internal combustion engine (ICE). Looking as surreal as the watches in Salvador Dali's "The Persistence of Memory" painting, the pistons' shape conforms to the arched cylinder in which it reciprocates a few thousand times per minute. How someone thinks up a scheme like this is beyond me. It took a couple readings to truly get a grasp on the operation. The writer is a bit misleading when asserting that the pistons are not really reciprocating in the cylinders, but in fact they are; they are just not driven by the traditional crankshaft. The engine's configuration reminds me of a modern brushless motor where the armature remains fixed and the field...

Every once in a while having your own website pays off by having someone offer hard- or difficult-to-find information. Back in 2016 when I originally posted the Radio Service Data Sheet (RSDS) for the Columbia Screen-Grid 8 (SG-8) Receiver, no photo could be found online. Notice hugeness of the components on top of the electronics chassis - the vacuum tubes, the metal shields, the transformers, the coils, etc. I always put in a fair amount of effort to find actual pictures of the radios. An image search usually does the job, but sometimes there is nothing to be found. This RSDS appeared in the October 1930 issue of Radio-Craft magazine. Typical of the era is a very ornate wooden chassis, and note the tiny tuning window in the center - no round dial or linear frequency scale...

High Life: The Bill Comes Due

According to Electronics magazine editor Lewis Young in mid-1964, the industry was entering into a slump in business opportunities. The boom times provided during the war years of WWII and Korea had resulted in, according to Mr. Young, a lax attitude toward operational strategy that led to wasteful spending and poor accountability for project results. It wasn't just the defense contractors' fault because government bureaucrats - from relatively low ranking military personnel to elected lawmakers - had (have) a habit of making sudden changes to contract requirements. Maintaining the resources needed to keep up with ever-evolving demands necessitated a lot of the excess. Fortunately, the military-industrial complex, as President Dwight D. Eisenhower dubbed it, was on the verge of being thrown another huge monetary bone - the Vietnam War. President Kennedy was already pumping lots of equipment and manpower into it, and LBJ would follow suit with vigor. The money pipeline was filling up quickly; the electronics industry was to be saved once again...

RAN Market Is "Still a Disaster"

"The Radio Access Network (RAN) market is "still struggling," according to the latest report from telecom analysts Dell'Oro Group. The first quarter of 2024 saw exceptionally weak results, with a decline of 15-30% in the overall global RAN market - the steepest decline since Dell'Oro started covering this market in 2000, according to Stefan Pongratz, Dell'Oro VP and analyst. Dell'Oro measures the sector by both revenue and units sold, but "the focus is on revenue," Pongratz said. Huawei, Ericsson, Nokia, ZTE and Samsung are the top five RAN suppliers, based on worldwide revenues. The vendors' positions remained stable but 'there have been shifts in vendor shares,' Dell'Oro said in an email. 'Huawei's 4QT revenue share improved relative to 2023, while Nokia lost ground over the same period.' So, we can look forward to dour first-quarter results from our Nordic friends at Nokia and Ericsson, following disappointing fourth-quarter results. Ericsson said that it would cut 1,200 Swedish staff in March 2024. This follows planned cuts of 8,500 people worldwide..."

Mac's Service Shop: Electronics and the Energy Crisis

I'm old enough to remember the 1973 Oil Crisis era (the subject of Mac McGregor's and Barney's discussion) that resulted from an oil embargo instituted by Arab oil producing nations during the Yom Kippur War where Egypt and Syria launched a surprise attack on Israel. I didn't get my driver's license until Fall of 1974 (turned 16 on August 18th), so the worst of it was pretty much over by then. However, I clearly remember sitting in long lines at the gas station with my father, and then being limited in the amount that could be purchased (i.e., no fill-ups). Gas prices jumped from a national average of 38.5¢/gallon in May 1973 to 55.1¢/gallon in June 1974 (43% increase in a year). According to the BLS' Inflation Calculator, that is the equivalent of about \$3.52/gallon in 2024 money. That's about what gas is costing right now, so today we're paying oil embargo era rates (thank you Brandon). If you were fortunate enough to own a boat during those times...

Espresso Engineering Workbook™ for Excel

The newest release of RF Cafe's spreadsheet (Excel) based engineering and science calculator is now available - Espresso Engineering Workbook™. Among other additions, it now has a Butterworth Bandpass Calculator, and a Highpass Filter Calculator that does not just gain, but also phase and group delay! Since 2002, the original Calculator Workbook has been available as a free download. Continuing the tradition, RF Cafe Espresso Engineering Workbook™ is also provided at no cost, compliments of my generous sponsors. The original calculators are included, but with a vastly expanded and improved user interface. Error-trapped user input cells help prevent entry of invalid values. An extensive use of Visual Basic for Applications (VBA) functions now do most of the heavy lifting with calculations, and facilitates a wide user-selectable choice of units for voltage, frequency, speed, temperature, power, wavelength, weight, etc. In fact, a full page of units conversion calculators is included. A particularly handy feature is the ability to specify the the number of significant digits to display. Drop-down menus are provided for convenience...

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

Empower RF Systems is the technological leader in RF & microwave power amplifier solutions for EW, Radar, Satcom, Threat Simulation, Communications, and Product Testing. Our air and liquid cooled amplifiers incorporate the latest semiconductor and power combining technologies and with a patented architecture we build the most sophisticated and flexible COTS system amplifiers in the world. Solutions range from tens of watts to hundreds of kilowatts and includes basic PA modules to scalable rack systems.

Thursday the 16th

From the 1940s through the 1980s, National Radio Institute (NRI) ran full-page and multi-page advertisements in many electronics and technology magazines, including Popular Mechanics, Radio News, and here in this 1947 issue of Popular Science. I don't recall exactly how/where I learned of the NRI when I enrolled in their "Electronic Design Technology" course, circa 1987. At the time I was working as an electronics technician for Simmonds Precision Instruments in Vergennes, Vermont. That was immediately preceding my completing a Bachelor of Science degree in Electrical Engineering at the University of Vermont. My formal training in electronics began in the U.S. Air Force while attending technical school at Keesler AFB, Mississippi, for being an Air Traffic Control Radar Repairman. NRI president J. E. (James Ernest) Smith, whose face appeared regularly in the ads...

British engineer John Sargrove was to the production of radios what Henry Ford was to automobiles. At the time this "Robot Makes Radios" article appeared in a 1947 issue of Radio-Craft magazine, Sargrove had recently put his Electronic Circuit Making Equipment (ECME) fully automated assembly line into operation. Applying knowledge from two decades of developing methods of creating inductors, capacitors, resistors, and interconnecting conductors using controlled deposition of various materials on flat substrates, he was able to build 2-tube AC/DC radios at a rate of up to three per minute, with only two ECME operators - one at the input and one at the output. The only manual assembly required was the installation of a potentiometer-switch, a transformer, speaker, and a power cord, plus joining the two fabricated Bakelite plates together. You will be amazed at what Mr. Sargrove's machine did. Unfortunately, raw material shortages after a grueling war...

U.S. to Triple Its Semiconductor Manufacturing

"Whether its lobbying in favor in the industry it represents, ensuring that public policies are promoting innovation or helping to unite all players in the space, the Semiconductor Industry Association (SIA) works tirelessly to support the U.S. semiconductor industry. The group also has its finger on the pulse of the domestic chip manufacturing sector, which it now says is on track to triple in size by 2032. In their new Emerging Resilience in the Semiconductor Supply Chain report, SIA and Boston Consulting Group paint the picture of a sector that’s shaken off the negative impacts of the global pandemic and great chip shortage, and that’s well positioned to thrive and expand over the next eight years. Government funding will play a key role in that expansion. The US CHIPS Act, signed into law in August 2022, committed \$39 billion in grants and loans for semiconductor manufacturing..."

Transistor Circuitry

Transistor basics have not changed since they were first introduced to the market around 1953, when this issue of QST magazine reported on them. The first available transistors used germanium substrates, and then in 1954 Texas Instruments introduced the first commercial silicon transistor. The hybrid pi equivalent circuit for a PN junction transistor used in modern circuit simulators has many more "virtual" components in it that allow for high frequency and nonlinear operation modeling, but for audio and AM type that operates entirely within the linear region, the equivalent circuit presented in Figure 1 will still get the job done. Common-(aka grounded-) emitter, common-base, and common-collector circuits are discussed. I remember in college in the mid 1980s running SPICE simulations on an IBM XT computer where the transistor model...

Promote Your Company on RF Cafe

Banner Ads are rotated in all locations on the page! RF Cafe typically receives 8,000-15,000 visits each weekday. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 17,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. Your Banner Ads are displayed on average 280,000 times per year! 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...

Many Thanks to Centric RF for Their Continued Support!

Centric RF is a company offering from stock various RF and Microwave coaxial components, including attenuators, adapters, cable assemblies, terminations, power dividers, and more. We believe in offering high performance parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz at power levels from 0.5-500 watts are available off the shelf. We have >500,000 RF and Microwave passive components we can ship you today! We offer Quality Precision Parts, Competitive Pricing, Easy Shopping, Fast Delivery. We're happy to provide custom parts, such as custom cables and adapters, to fit your needs. Centric RF is currently seeking distributors, so please contact us if interested. Visit Centric RF today.

Wednesday the 15th

Do It With Diodes

"Do it with <fill in the blank>," was a popular form of saying back in the 1960s and 70s. It is a form of double entendre, so people thought it was clever. I never did. This "Do It With Diodes" article from a 1961 issue of Radio Electronics magazine is an example. The term "diode" was not new to the electronics field at the time, as vacuum tube diodes and selenium rectifiers had been around for half a century. However, the newfangled semiconductor form of diodes were just coming on the scene. Germanium and silicon were the compounds available for commercial devices. More exotic materials were still in research laboratories. Author Donald Stoner provides a layman's level introduction to semiconductor diode fabrication and operation. Voltage, current, and power handling capacity was still fairly low. Prices for common diode types had dropped to a point that were making them competitive options...

Anatech Intros 3 New Filters for May

Anatech Electronics 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. Three new filters have been announced for May 2024 - a 5520 to 5540 MHz cavity bandpass filter with a passband insertion loss of 1.75 dB and ripple of <0.2 dB, a 4755 to 5000 MHz cavity bandpass filter with a minimum passband return loss of 15 dB, and a 4395 to 4955 MHz cavity bandpass filter with a minimum rejection of 35 dB at 4295 MHz and 80 dB at 5250 MHz. Custom RF power filter and directional couplers designs can be designed and produced...

Electronics-Themed Comics

Good, clean humor has always been a welcome addition to my day whether it comes in the form of a printed comic strip, a TV show, or someone's mouth. My father's side of the family was populated with many jokesters who could be counted on to deliver an ad hoc pun or zinger at the appropriate moment. The environment instilled a great appreciation for such entertainment, so these electronics-themed comics that appeared in editions of trade and hobby magazines like Radio-Electronics, Popular Electronics, et al, are a refreshing distraction from the workaday world. An old saying claims "laughter is the best medicine*," and while it cannot cure cancer, a good dose of humor often helps ease the pain...

Bluetooth into Low Earth Orbit

"A recent Bluetooth connection between a device on Earth and a satellite in orbit signals a potential new space race - this time, for global location-tracking networks. Seattle-based startup Hubble Network announced today that it had a letter of understanding with San Francisco-based startup Life360 to develop a global, satellite-based Internet of Things (IoT) tracking system. The announcement follows on the heels of a 29 April announcement from Hubble Network that it had established the first Bluetooth connection between a device on Earth and a satellite. The pair of announcements sets the stage for an IoT tracking system that aims to rival Apple's AirTags, Samsung's Galaxy SmartTag2, and the Cube GPS Tracker. Bluetooth, the wireless technology that connects home speakers..."

Short Waves and War

Here in one short editorial article, Hugo Gernsback outlines the application of shortwaves in "the next war" to maintain wireless surveillance of the airspace over towns and cities via what is essentially radar, to detonate explosive devices by means of a powerful "special combination impulse," and long-distance wireless communications via radios "so small that one man can easily carry it." This might seem rather moot in today's world, but in 1935 when this issue of Short Wave Craft magazine went to press, it required a certain amount of knowledge of wireless communications and a vision regarding its potential. In my readings of a great many early- to mid-20th-century technical articles on electronics, aeronautics, physics, etc., it is interesting to notice how authors of the pre-WWII era referred to what we now call "World War I" as simply "the World War..."

RF Cascade Workbook 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 (click here for screen capture). 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 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...

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page. About RF Cafe.

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