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SpaceX Plans 150 MBps D2D per User

SpaceX 150 MBps D2D - RF Cafe"SpaceX satellite policy lead Udrivolf Pica told participants in the International Telecommunication Union Space Connect webcast about the next-generation Starlink direct-to-device (D2D) cellular service for smartphones. The revelation of the new service follows SpaceX's October 2025 U.S. trademark filing for "STARLINK MOBILE" and comes as Elon Musk has recently hinted at Starlink mobile ambitions. 'We are aiming at peak speeds of 150 Mbps per user,' Pica said, adding, 'So something incredible if you think about the link budgets from space to the mobile phone..."

The Fixed "Rotary" Beam Antenna

The Fixed "Rotary" Beam Antenna, August 1940 QST - RF CafeOn a fairly regular occasion someone will write to one of the QST magazine columnists or post on a forum asking about information on a particular antenna configuration he recalled seeing printed many moons ago, but can no longer find anything on it. Fortunately, the columnists are guys who have been in the Ham game for a many decades and not only remember what the writer references, but knows where to dig out the original info. Even with the plethora of resources available on the Web, some things still cannot be found because nobody yet has posted it. That is one of my prime...

Amateurs Honor Hiram Percy Maxim

Amateurs Honor Hiram Percy Maxim, August 1940 QST - RF CafeHiram Percy Maxim is well-known by amateur radio operators as the founder of the American Radio Relay League (ARRL). He died in 1936 and was buried at Rose Hill Cemetery in Hagerstown, Maryland. A few years ago while visiting relatives in Hagerstown, I went to the cemetery, took some photos, got the exact GPS coordinates, and posted a short article on it (see Hiram Percy Maxim's Gravesite in Hagerstown, Maryland). If not for my documentation, there would be no way to know that the large grave marker shown in this 1940 QST magazine article does not belong to the esteemed Mr. Maxim, but to the matron of his wife's family...

High Tech Comics: July 1961 Electronics World

High Tech Comics, July 1961 Electronics World - RF CafeHere are a couple high tech comics for your enjoyment from the pages of the July 1961 edition of Electronics World magazine. I'm guessing the joke in the page 72 comic is that unknown parts were/are generically referred to as "Brand X," so hopefully that would bring in customers who couldn't identify components (which the repairman probably could). It could also be an unintended warning that if "Brand X" (knockoff part) is sold there, then there is a good chance inferior parts will be used in the repair. The page 94 comic is yet another play on the huge popularity of home hi-fidelity (hi-fi) sound systems of the day. Amplifiers still used vacuum tubes so building speaker driver circuits that could handle hundreds of watts was easy to do...

Men Who Have Made Radio - Heinrich Hertz

Men Who Have Made Radio - Heinrich Hertz, February 1930 Radio-Craft - RF CafeFifth in the "Men Who Have Made Radio" series, Heinrich Hertz is honored here for giving mankind what author Hugo Gernsback appropriately termed "a sixth sense." Having earned his doctorate with a thesis on "the distribution of electricity over the surface of moving conductors," Hertz proved through his experiments the existence of electromagnetic waves - the aforementioned sixth sense. During his short 37 years on Earth, Heinrich Hertz accomplished an impressive amount of fundamental research and discovery. He was remembered fondly as a kind man who placed advancing the frontiers of science ahead of fighting for credit...

Werbel 9-Way Resistive Splitter for DC-7.2 GHz

Werbel Microwave WMRD09-7.2-S 9-Way Resistive Power Splitter for DC-7.2 GHz - RF CafeWerbel Microwave began as a consulting firm, specializing in RF components design, with the ability to rapidly spin low volume prototypes. The WMRD09-7.2-S is a 9-way resistive splitter that covers from DC to 7.2 GHz with ultra-wide bandwidth. This unique design accomplishes extremely flat frequency response in a small radial package. Our unique design approach provides higher than expected isolation between outputs at far ports than would be achieved in a typical star topology. It has applications in markets such as CATV, T&M, and military radio...

"This Is Digi-Talker"

"This Is DigiTalker" - RF CafeWhile watching the Avengers: Age of Ultron movie, at some point when one of the computer voices was speaking, a memory of the "This Is DigiTalker" voice suddenly came to mind. Back in the mid-1980s while working at Westinghouse in Annapolis, Maryland, a couple of the engineers brought a DigiTalker prototype experimentation board into the super-classified area where I worked. According to National Semiconductor's datasheet, it was introduced sometime around 1980. The programmable digital voice IC was a big deal in that unlike other devices that had a fixed set of...

Please Thank IPP for Their Long-Time Support!

Innovative Power ProductsInnovative Power Products has been designing and manufacturing RF and Microwave passive components since 2005. We use the latest design tools available to build our baluns, 90-degree couplers, directional couplers, combiners/dividers, single-ended transformers, resistors, terminations, and custom products. Applications in military, medical, industrial, and commercial markets are serviced around the world. Products listed on the website link to detailed mechanical drawings, electrical specifications, and performance data. If you cannot find a product that meets your requirements on our website, contact us to speak with one of our experienced design engineers about your project.

Teach Kids Electricity

Teach Kids Electricity, June 1958 Popular Electronics - RF CafeSome things never change - at least at the fundamentals level. Electric circuits is one of those things. I don't remember when I first became interested in electrical apperati, but it must have been due to a natural affinity to the science because nobody in my family or my circle of friends expressed any interest. I was the odd man (or boy) out on my street, because while all the other kids were playing baseball, basketball, and football, I was sticking forks in electric sockets and disassembling flashlights, battery-powered toys, and building Erector Set contraptions using the included electric motor. That's not to say I ever got really good at it, but significantly better than I ever got at playing sports...

Impedance Matching CB Antennas

Impedance Matching CB Antennas, July 1961 Electronics World - RF CafeYou would be forgiven in this era of ubiquitous cellphone usage for thinking maybe Citizen Band (CB) radios are only used these days by techno-throwbacks like myself, but the fact is many truckers still use them for convenience as well as to avoid having all their communications intercepted, monitored, and recorded by government agencies. It can be a deceiving sense of privacy though, because police officers often monitor CB radio transmissions while in patrol cars, and even solicit the assistance of other CBers in identifying and apprehending suspected transgressors - an advantage of public, unencrypted conversation afforded law enforcement which is not available with cellphones. Also, CB transmission, even though usually regarded as "hearsay" in legal venues, has many times been admitted as evidence in cases where "present sense impression," "excited utterance," or some other special...

AI Math Tricks no Good for Science

AIs Math Tricks Don’t Work for Scientific Computing - RF CafeI have experienced the problem with low precision AI calculations; however, it will use high precision if specifically instructed to do so. "AI has driven an explosion of new number formats - the ways in which numbers are represented digitally. Engineers are looking at every possible way to save computation time and energy, including shortening the number of bits used to represent data. But what works for AI doesn't necessarily work for scientific computing, be it for computational physics, biology, fluid dynamics, or engineering simulations. IEEE Spectrum spoke with Laslo Hunhold..."

Science & Engineering Crossword Puzzle

Sceince & Engineering Crossword Puzzle for 9/20/2015 - RF CafeThis week's Science & Engineering Crossword Puzzle, as is the case with all RF Cafe crossword puzzles, has only words and clues related to science and engineering. Each week for two decades I have created a new technology-themed crossword puzzle using only words (1,000s of them) from my custom-created lexicon related to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, find someone or something in the otherwise excluded list directly related to this puzzle's technology theme, such as Hedy Lamarr or the Bikini Atoll, respectively. Avid cruciverbalists amongst us: the gauntlet has been thrown down.

Frenzied Radio

Frenzied Radio, February 1930 Radio-Craft - RF Cafe"And there is nothing new under the sun." - Ecclesiastes 1:9, NKJV (did you know that is the origin of the saying?). This 1930 editorial by Radio-Craft editor Hugo Gernsback describes a coordinated scam perpetrated by radio manufacturers to compel consumers to buy new sets rather than have their existing sets repaired. In short, retail prices were inflated to accommodate a built-in 'trade-in' allowance that far exceeded the repair cost or used radio cost. Radio service shops were getting the short shrift because many people who might have otherwise elected to have repairs made would instead trade in the old set for a new one...

Television in Twelve Colors

Television in Twelve Colors, October 1930 Radio-Craft - RF CafeIt really wasn't all that long ago when most people worked on computers with Color Graphics Adapter (CGA) that had just 16 colors (4-bit pixels). In the late 1980s (wow, maybe it really was a long time ago), the luxury of a 256-color (8-bit pixels) Video Graphics Adapter (VGA) monitor and video card would cost you around $300 each. I recall seeing ads for "16 million color" displays by ViewSonic that ran north of a kilobuck. My first "real" monitor was bought in 1987 and was 4-bit monochrome. Televisions, as you know, began as black and white (actually a infinite number of gray levels between black and white). When TVs first arrived in people's homes, they were glad for any kind of display, but it wasn't long before marketing gurus convinced the masses that...

To Be, Or Not to Be [a Metal] - Kirt's Cogitations™ #374

To Be, Or Not to Be [a Metal] - Do Astrophysicists Know the Difference?: Kirt's Cogitations™ #374 - RF CafeAs a multi-decade-long amateur astronomer, I have read countless articles written by astronomers who refer to all elements heavier than helium (#2 on the periodic table of the elements) as "metals." Ostensibly, the origin stems from early detection of heavy elements in stars, based on heliographic spectrum investigations, where iron - being the most abundant stable byproduct of supernova explosions - was most readily observed. I wondered if the "metals" nomenclature came from the next heaviest element, lithium (#3 in the periodic table), being a metal, thereby laying the foundation. Not so, claims AI, since lithium is very rare overall in the universe, and not readily observed. For clarity, I also procured the scientific distinction...

Mac's Radio Service Shop: Mac and Free Estimates

Mac's Radio Service Shop: Mac and Free Estimates, January 1950 Radio & Television News - RF CafeI usually learn something new with each episode of Mac's Radio Service Shop, but not necessarily related to electronics. Such is the case this time where after Mac gives Barney a quick lesson in how to determine a transformer's winding turns ratio when needing to create an impedance match circuit. He then, while discussing whether "free" repair estimates are truly free or of any real value at all, he uses the phrase "a horse on you." Maybe it is because I don't frequent bars that I had never heard that, but after a little research I now know it refers to a bar dice game called "'Horse." "A horse on you" is when you lose the final round of a 2-out-of-3 challenge. "A horse apiece" is when you and your opponent each win one round in a 2-out-of-3...

Superconductors in AI Data Centers

AI Data Centers Turn to High-Temperature Superconductors - RF Cafe"Data centers for AI are turning the world of power generation on its head. There isn't enough power capacity on the grid to even come close to how much energy is needed for the number being built. And traditional transmission and distribution networks aren't efficient enough to take full advantage of all the power available. According to the U.S. Energy Information Administration, annual transmission and distribution losses average about 5%. The rate is much higher in some other parts of the world. Hence, hyperscalers such as Amazon Web Services, Google Cloud and Microsoft Azure are investigating every avenue to gain more power and raise efficiency. The potential virtues of high-temperature superconductors..."

The Coming Breakthrough in Thermoelectricity

The Coming Breakthrough in Thermoelectricity, July 1961 Electronics World - RF CafeConsumer grade thermoelectric coolers have been around for so long now that most people probably assume there is nothing wondrous about the discovery that makes them possible. I still marvel at the process that allows the application of a current through physical junction of two dissimilar metals (certain types) to produce a cooling effect rather than the I2R heating normally associated with conductors. This article from a scientist at Westinghouse Electric's research laboratories provides a nice introduction to the subject of thermoelectricity from both electric current generation based on the application of heat to a dissimilar metals junction, and the aforementioned cooling effect possible from passing a current...

Stereophonic FM Multiplex System

Stereophonic FM Multiplex System, July 1961 Electronics World - RF CafeFM radio has been in the news fairly frequently in the last couple years as phone manufacturers and the National Association of Broadcasters lobby the FCC and politicians to mandate the inclusion of FM radio capability into every phone manufactured. In a ploy to exploit the gullibility and egos of said bureaucrats and pols, their primary argument that FM radio is a "first informer in times of crisis," assuming of course that people will miss news of "the big one" when and if it occurs. To my knowledge, successful reception of FM radio on a cellphone requires the listener wear a set of wired ear buds since the wire from the phone to the ear buds functions as the antenna. What percentage of cellphone users would bother to carry a set of ear buds? I, of course, am a huge proponent of...

Popular Electronics Crossword Puzzle

Arthur Brach created many crossword puzzles for Popular Electronics magazine in the 1950s and 1960s. Unlike the hundreds of RF Cafe Crossword Puzzles I designed over more than two decades, the PE puzzles usually have a few words that are not specifically related to electronics and/or technology. Still, they are a good source of a brief break from the day's business. You will need to print out this crossword puzzle to work it, since it is not interactive. Have fun.

Is Fair Trade the Answer to TV Price Cutting Problem?

Is Fair Trade The Answer to TV Price Cutting Problem?, October 1949 Radio & Television News - RF Cafe"Fair Trade" was a policy established in the post-WWII era in response to what consumer retail groups considered business-ruining cost cutting by dealers who offered to sell products at or barely above cost in order to steal profit from other stores. So-scheming stores planned to make up for the low profit margin with high sales volumes. Doing so drove a lot of the local competition out of business, leaving the crafty dirty dealers to later raise prices. Stores that had manufacturer-sanctioned service shops often got screwed because they were obligated to repair items like TVs and radios that were bought from another dealer who did not do service work. Profit margins on repair work - at least from honest shops - were typically very low, so the owners depended on new product sales...

Quantum Teleportation: What's New

Quantum Telecom: What's New - RF CafeYowza, yowza, yowza (The Jazz Singer), QentComm's stock will be rising soon! "Quantum technology is already alive and well in telecom networks, and although security is the top-of-mind use case, telcos are also looking at quantum to make networks more resilient and transmit information more quickly. Comcast announced this week it completed a trial with AMD and Classiq that leveraged quantum software to find independent backup paths for network sites. Elsewhere, Deutsche Telekom and Qunnect successfully demonstrated quantum teleportation over an existing fiber network in Berlin..."

Technical Headlines - RF Cafe

• FCC Expands Unlicensed Use of 6 GHz Band

• Active Smartphone Installed Base up 2% in 2025

• FDA Clarifies Wearable Device Rules

• Revisiting the 1996 Telecommunications Act

• China's BeiDou Satellite (their GPS) Does Emergency Messaging

• How & When Will Memory Chip Shortage End?

Today in Science History - RF Cafe
Homepage Archives - RF Cafe

The RF Cafe Homepage Archive is a comprehensive collection of every item appearing daily on this website since 2008 - and many from earlier years. Many thousands of pages of unique content have been added since then.

Using Selenium Rectifiers

Using Selenium Rectifiers, October 1947 QST - RF CafeThe advent of selenium rectifiers in the 1940s was a very welcome new option to circuit designers, consumers, and servicemen. Before that, vacuum tubes did the job (with some use of copper oxide rectifiers). Selenium rectifiers have the advantage of ruggedness and reliability over tubes (~85% vs. ~60%, respectively). Not requiring a heater voltage eliminates needing to create heat in excess of that dissipated due to the innate inefficiency. Voltage and power handling is adjusted by stacking appropriate layers and adjusting the physical size, respectively. A failed selenium rectifier reportedly often emitted a very foul odor, which although offensive to the user, proved to be a nice bonus for the serviceman since it immediately gave a clue as to what went wrong...

Square D Model 5008 Voltage Tester

Square D / Wigginton "Wiggy" Model 5008 Voltage Tester - RF Cafe Cool ProductSometime in the mid 1970's while working as an electrician, I bought this Square D / Wigginton (aka the "Wiggy") Model 5008 Voltage Tester. It was probably considered high tech in the day. It uses a simple solenoid to drive the indicator needle. The scale begins at 120 volts and ends at 600 volts on the alternating current (A.C.) side, and 120 through 400 volts on the direct current (D.C.) side. Surprisingly little information on the 5008 is available on the Web. Close-up of the business area of the Square D model 5008 Voltage Tester. Information sheet for the 5008. Direct current (D.C.) polarity indicator. Example of measuring house voltage with the Square D model 5008 Voltage Tester. The highest voltage I ever measured with it was 480 VAC (3-phase), supplying a concrete block forming machine in Annapolis, Maryland. It was kind of a spooky experience. I'm comfortable around 240 VAC, but above that level I worry about compromised insulation, especially in damp environments. Even with the availability of much more sophisticated analog and digital multimeters, this is still my instrument of choice when working on house circuits. It is still in very nice condition and gets used on a regular basis - as recently as a couple days ago when adding a couple circuits to my daughter's horse barn...

Why Use a Triac?

Why Use a Triac?, April 1974 Popular Electronics - RF CafeTriacs are not a component often used in RF and microwave circuit design, but being conversant in its operation could make you popular at nerd parties. A triac is basically the equivalent of two SCRs connected back-to-back, allowing it to conduct on both the positive and negative half-cycles of an AC connection. Both devices are most commonly used in switching applications. The unique feature of an SCR and triac is that once the gate voltage is sufficiently high to begin conduction between the anode and cathode, it can be removed and conduction will continue until the anode-cathode voltage is removed...

Sperry Gyroscope Company

Sperry Gyroscope Company, October 1944 Radio News - RF CafeThis 1944 advertisement from Sperry Gyroscope Company claims it owns the copyright for the word "Klystron." According to the Wikipedia entry: "The name klystron comes from the Greek verb κλύζω (klyzo) referring to the action of waves breaking against a shore, and the suffix -τρον ("tron") meaning the place where the action happens. The name "klystron" was suggested by Hermann Fränkel, a professor in the classics department at Stanford University when the klystron was under development." Furthermore, it says American electrical engineering brothers Russell and Sigurd Varian were the inventors of the klystron. The video helps explain how the klystron tube works. I am always amazed at how someone came up with such an idea in the first place. This is the earliest patent, dated 1938...

Amelia Earhart's Short-Wave Radio Never Failed

Amelia Earhart's Short-Wave Radio Never Failed, April 1935 Short Wave Craft - RF CafePlenty of intrigue still surrounds the July 2, 1937, disappearance of Amelia Earhart in the South Pacific on her way to completing an around-the-world flight. This article appeared two years prior to that fateful flight proclaiming the soundness (no pun intended) of her onboard radio. Back in the day, shortwave radio installations in aircraft required long wires trailing behind, particularly for long distance requirements like flying from the U.S. mainland to Hawaii. Those wires were a constant source of trouble due to destructive mechanical oscillations while waving in the airstream, airframe damage due to striking during the haul in/out procedure, and breakage. According to an article that appeared in the January 2015 edition of Smithsonian magazine, it is suspected that Earhart's antenna broke early in her flight and that is what was responsible for the loss of communication. Navy ships were tasked to monitor her progress and reported picking up spotty transmissions, but she never responded to messages...

Electronics-Themed Comics

Electronics-Themed Comics March 1952 Radio & TV News - RF CafeThese two electronics-themed comics appeared in a 1952 edition of Radio & Television News magazine. In the early days of television, it was common in comedy skits and in cartoons to have someone on a television show interact, to the viewer's great shock, directly with the viewer or to reach out of the set and do something, as in the first comic here. The Three Stooges show did that in a couple shows. One in particular I remember was when they were doing plumbing in a house and had water coming out of light sockets and telephones. The homeowners were watching the TV with a film of Niagara Falls when suddenly water came gushing out of the picture tube (begins at 13:20 in video)...

Space Electronics

Space Electronics, April 1961 Popular Electronics - RF CafeThe late 1950s and early 1960s were the dawn of the Space Age, beginning unofficially with the launch of Sputnik. Popular Electronics magazine put a lot of effort into educating the public on advances in space electronics, including not just the spaceborne platforms, but also ground tracking and communicating equipment. Much hardware was launched into orbit in the early years without giving much thought to the hazards or space debris. Failures in the form of explosions scattered chunks widely, but fortunately most were low enough to have their orbits degrade and re-enter the atmosphere. One interesting tidbit reported in this article that I didn't know was that the TV camera lens on the TIROS 2 weather satellite was defocused during launch (due to positional shifting from vibration and G forces, I suppose) and crippled the image quality severely...

Radio-Electronics Monthly Review

Radio-Electronics Monthly Review, October 1945 Radio-Craft - RF CafeOn December 8, 1941, the day after the Japanese attack on Pearl Harbor, the FCC issued a "Notice to All Amateur Licensees" that began thusly: "All amateur licensees are hereby notified that the Commission has ordered the immediate suspension of all amateur radio operation in the continental United States, its territories, and possessions." The October 1945 issue of Radio-Craft magazine announced the long-awaited planned resumption of transmitting operations. On November 15, 1945, amateurs were finally allowed back on the air, but only on the 10 and 2 meter bands. Another end to an FCC wartime policy announced was the requirement to reduce output power by 1 dB (~20%) below normal maximum power, with the motivation having been to extend the lifetime of tubes. Proving that engineers and major corporations can have a sense of humor, get a load of the "sniffer" radar dish shown here...

Engineering & Science Crossword Puzzle for July 7

Engineering & Science Crossword Puzzle July 7, 2019 - RF CafeThese custom-made engineering and science-themed crossword puzzles are done weekly for the brain-exercising benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. The jury is out on whether or not this type of mental challenge helps keep your gray matter from atrophying in old age, but it certainly helps maintain your vocabulary and cognitive skills at all ages. A database of thousands of words has been built up over the years and contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc. 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...

First Phone Broadcast

First Phone Broadcast, January 1947 Radio-Craft - RF CafeAfter having read many articles about Dr. Lee de Forest, it seems the poor guy was besieged his entire life by envious and/or belligerent electronic communications compatriots who sought to defame him and/or deny him of monetary rewards. This January 1947 issue of Radio-Craft magazine includes a dozen or so pieces written by friends and colleagues who recognized the momentous struggles and achievements of Dr. de Forest. Such burdens of fame are borne by many - if not all - persons of similar celebrity. Dogged persistence is the order of the day for experimenters and breakers-through of assumedly impenetrable walls. Guys like de Forest lived by the old adage recommending that "if at first you don't succeed, try, try again." You'll be amazed at how de Forest whipped - almost literally - that thing which was preventing his wireless telephone from working. BTW, as I've pointed out before, you will find the good doctor's last name written as "de Forest, DeForest, and De Forest." As evidenced by his signature...

Electronics Theme Crossword for Easter Sunday

Electronics Theme Crossword Puzzle for Easter Sunday, April 9, 2023 - RF CafeThis custom RF Cafe electronics-themed crossword puzzle for April 9th, Easter Sunday, contains words and clues which pertain exclusively to the subjects of electronics, science, physics, mechanics, engineering, power distribution, astronomy, chemistry, etc. It'll keep you busy while the kids hunt for Easter eggs. If you do see names of people or places, they are intimately related to the aforementioned areas of study. As always, you will find no references to numbnut movie stars or fashion designers. Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds of them dating back to the year 2000. Enjoy.

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeBanner 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 225,000 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...

High Frequency Heating at a Glance

High Frequency Heating at a Glance, May 1945 Radio-Craft - RF CafeChances are when you think about high power RF frequency sources, it pertains to transmitters for analog or digital data, or maybe for imaging applications like x-ray machines. There is, however, another very large industry that uses high frequency electromagnetic energy for heating of materials in product processing. Frequencies range from tens of kilohertz to tens of megahertz, with power levels into the megawatt realm. This article from a 1945 edition of Radio-Craft points out a few applications used in the day, and now there are many more areas where high power RF is used. Adhesive curing is a major area, especially for laminated materials like plywood and composite structures. Decontamination of medical and food products is another. Both inductive and capacitative heating methods are used in metals processing...

Man into Space?

Man Into Space?, June 1961 Radio-Electronics - RF CafeAccording to the postscript to this editorial, Hugo Gernsback wrote his opinion on the then current state of space exploration and his recommendation for how future efforts should proceed, a month before Alan Shepherd made his historic suborbital flight aboard the Freedom 7 Mercury capsule. That May 5, 1961, feat marked mankind's first foray into space. Surprisingly, Gernsback was not in favor of a manned space program. He believed the resources and expense required to support human life in space would be better invested in developing autonomous and remotely controlled robotic systems. Many people agreed with him then and today. Although I do not oppose manned space flight, I tend to agree with Gernsback that much more can be accomplished with machines than with humans. NASA's many successes on Mars are evidence of the accomplishments possible with robots, and the long-term missions possible. At some point it might be necessary to explore sending men to other planets, but there really is no imperative at this time - just a desire to do so. Coincidentally (or maybe not so coincidentally), Mr. Gernsback refers to his vision of a lunar probe as "surveyor," which was name of NASA's series of robotic lunar lander probes deployed...

21 Years a Ham

21 Years a Ham, September 1950 Radio & Television News Article - RF CafeThe title says "21 Years a Ham," and that was true in 1950 when this story appeared in Radio & Television News magazine. However, 72 years later author Helen Cloutier can claim "93 Years a Ham," if she has not yet obtained Silent Key (SK) status. As with today, as far back as the middle of the last century organizations and publications went out of their way to celebrate and promote "non-traditional" participants, in this case a woman, engaged in the hobby, sport, or profession. Concurrently, those same groups were accused of discouraging and shunning women and minorities from participation (yes, of course some were guilty of it). Special accommodations - even laws - were made to right the accused wrong. It simply can't be that males (particularly white males) might be more interested in those particular activities than others. For many decades, white males have been placed at a disadvantage regarding access to schools, jobs, political office, and organizations, in favor of everyone else. It is the only acceptable form of discrimination (see the update with her incredible obituary from 2002)...

Civilian Radio Jobs Wanted - Free Want-Ad Service

Civilian Radio Jobs Wanted - Free Want-Ad Service, May 1946, Radio-Craft - RF CafeWhile everyone greatly welcomed the ending of World War II, in its wake was a huge number of people that would be in need of jobs. Many thousands of men had been trained in the field of electronics maintenance and hope to exploit those skills in doing service work in radio, television, industrial controls, and other related fields. Other planned to go into sales, or a combination of both. Some had been in the business prior to either volunteering or getting drafted into the war, but not all could expect to simply pick up where they had left off. In order to assist the country's servicemen in transitioning into civilian life, Radio-Craft magazine provided a free service where individuals could list their qualifications, along with contact information - effectively an abbreviated resume posting venue...

Men Who Made Radio - Sir Oliver Lodge

Men Who Made Radio - Sir Oliver Lodge, December 1929, Radio-Craft - RF CafeRadio-Craft magazine ran a monthly series of short articles paying tribute to some of the shakers and movers in the field of science - this time it was Sir Oliver Lodge. "While Hertz was discovering radio waves in air, Lodge was determining the laws of the corresponding activity which takes place in electrical conductors. It was Lodge who demonstrated the possibility of radio communication, experimentally, as Marconi did its commercial value - just as Henry created the telegraph and Morse made it of practical utility." See other "Men Who Made Radio" features on...

Vintage Slide Rule Calculators

Cardboard Slide Rule Calculators Donated by Gary Steinhour - RF CafeSlide rules have come in different formats over the years. The most familiar is probably the 3-part model with a fixed outer frame and a sliding inner rod, and a sliding clear window with a reticle line etched into it for aligning numbers (the cursor). While far from being any type of "collection," I do have a couple nicely preserved models. The ones from Keufel & Esser (K&E) are at the top of the table below. The Beginner's slide rule model is very basic with graduations on one side and some conversions on the other. The best of all is the Pickett N600-ES Log-Log that is in new condition and actually still has the box, leather case, instructions and certificate. The Pickett N600-ES is the slide rule model that went to the moon* with the Apollo astronauts (not the one I own, of course)...