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Today in Science History

Charles Babbage: A Short Biography

Charles Babbage: A Short Biography - RF CafeCharles Babbage, born on December 26, 1791, in London, England, was one of the foremost mathematicians and inventors of the 19th century, best known for his pioneering work on the concept of a programmable computer. He was the son of Benjamin Babbage, a banker, and Betsy Plumleigh Teape, who hailed from a relatively affluent family. His upbringing was comfortable, allowing him access to an education that would later foster his intellectual pursuits. His father's wealth enabled Charles to attend some of the finest schools of the time, although his formal education started somewhat later than usual due to early childhood illness. Babbage's schooling began at a local academy in Alphington and later at the King Edward VI Grammar School in Totnes, Devon. He was a highly curious child...

Preventing Another Europa Clipper Transistor Panic

Preventing Another Europa Clipper Transistor Panic"Yesterday, NASA successfully launched the Europa Clipper, the largest spacecraft the agency has ever built for a planetary mission. Clipper is now successfully on its multi-year journey to Europa, bristling with equipment to study the Jovian moon's potential to support life - but just a few months ago, the mission was almost doomed. In July, researchers at NASA found out that a group of Europa Clipper's transistors would fail under Jupiter's extreme radiation levels. They spent months testing devices, updating their flight trajectories, and ultimately adding a warning “canary box” to monitor the effects of radiation as..."

Printed-Circuit Technology

Printed-Circuit Technology, October 1969 Electronics World - RF CafeThe October issue of Electronics World magazine included many articles written by printed circuit board (PCB) industry leaders regarding the state of the art. Multi-layer PCB technology was still in its infancy at the time, with most prototype and production boards being 1- or 2-sided. As with the switch from vacuum tubes to transistors, there were hold-outs who resisted the change to PCBs - for good reason in some cases. A list of advantages and disadvantages is presented both for and against, respectively, use of printed circuit boards. One of the biggest advantages to point-to-point wiring (i.e., in the PCB disadvantage list) was that circuit modifications in production was more easily accommodated, unless the change was simply...

FM Antennas for Better Listening

FM Antennas for Better Listening, February 1962 Radio-Electronics - RF CafeAlong with the advent of FM (frequency modulation) radio came an entirely new variety of antenna shapes and configurations, compared to primarily a simple long, straight wire for AM (amplitude modulation) radio antennas. Amateur radio operators (Hams) of course had been designing, tuning, and using such antennas (as FM) for decades, but the average radio listener was facing a whole new world of options for getting the most out of his receiver. It is not that AM radio cannot benefit by similar antenna configurations, it is just that the relatively long wavelength of AM station frequencies (540 to 1,700 kHz) compared to FM station frequencies (88 to 108 MHz) represents a two-order-of-magnitude...

Beyond Moore's Law: Revolutionary Hot Carrier Transistors

Beyond Moore's Law: Revolutionary Hot Carrier Transistors - RF Cafe"Researchers have developed a novel graphene-germanium hot-emitter transistor using a new hot carrier generation mechanism, achieving unprecedented performance. This advancement opens new possibilities for low-power, high-performance multifunctional devices. Transistors, the fundamental components of integrated circuits, encounter increasing difficulties as their size continues to shrink. To boost circuit performance, it has become essential to develop transistors that operate on innovative principles. Hot carrier transistors, which harness the extra kinetic energy of charge carriers, offer the potential to enhance transistor speed and functionality..."

Electronics-Themed Comics

Electronics-Themed Comics, August 1969 Electronics World - RF CafeWhen this was originally published, it was Labor Day in the USA, so most people were off work (which seems antithetical to the "labor" part of the holiday name). For those unfortunate enough to be at work, here is a bit of vintage electronic comic relief from a 1969 Electronics World magazine for your office-bound condition. Actually, during my years of working for someone else, I used to work the holidays (except Christmas) if I could get another day off instead. With very few managers around, those of us at work would enjoy what we termed "IPV," or "In-Plant-Vacation." Very little work got done on those days, and lunches and break-times were pretty long. I was always surprised the scheme never caught on more widely...

AMP2074P-2KW, 1.0–2.5 GHz, 2 kW Pulse SSPA

Exodus AMP2074P-2KW, 1.0–2.5 GHz, 2 kW Pulse SSPA - RF CafeExodus Advanced Communications, is a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide. We are pleased to announce the model AMP2083P-2KW solid state pulse amplifier (SSPA) is designed for Pulse/HIRF, EMC/EMI Mil-Std 461/464 and radar applications in the C-band, 4.0-8.0 GHz frequency band. Providing superb pulse fidelity and up to 100 μsec pulse widths. Duty cycles to 6% with a minimum 63 dB gain. Available monitoring parameters for Forward/Reflected power in watts & dBm, VSWR, voltage, current, temperature sensing for outstanding reliability and ruggedness in a compact...

Making Picture Tubes

Picture Tubes, May 1955 Popular Electronics - RF CafeBy the time most of us who even remember cathode ray tubes (CRTs) were first introduced to them, the technology and manufacturing processes had been pretty much perfected - especially for the standard 525-line (or 625-line outside the U.S.) resolution type. The National Television System Committee (NTSC) published a standard for black and white (B&W) television in 1941 and then for color in 1953. This "Picture Tubes" article in a 1955 issue of Popular Electronics provides a look inside a CRT manufacturing plant at General Electric. For some reason the photos in the magazine were very poor quality (maybe for secrecy). If you want one of the best explanations I have ever seen on how a TV picture scan is implemented, check out this video entitled What is 525-Line Analog Video? If you don't understand raster scanning after watching it, you never will. You might be surprised to learn that there were not actually 525 lines of picture information...

News Briefs

News Briefs, March 1962 Radio-Electronics - RF CafeThe March 1962 "News Briefs" feature in Radio-Electronics magazine was chock full of interesting developments. Space flight was a big deal in the day, not that it isn't today, but the difference is everything about it was new then. Fundamental technology was in the process of being developed, and then continual improvements would be made during the ensuing decades until we get to where we are today with a permanent presence of men in orbit, interplanetary science probes, space-borne telescopes, Earth environment sensors, and space weapons, and thousands of active communications satellites. The sky is awash with manmade objects. In other news, satellite TV was quickly gaining in capability (including live transmissions and, gasp, "Living Color" per NBC)...

Direct Conversion vs. Heterodyne vs. Superheterodyne

Direct Conversion vs. Heterodyne vs. Superheterodyne - RF CafeThe distinction between direct conversion, heterodyne, and superheterodyne receivers represents a significant evolution in radio technology. Each type of receiver plays a crucial role in the development of modern communications, and their invention marks important milestones in the history of radio engineering. To understand these differences, we will explore the invention history, technical descriptions, and practical implementations of each type, including their inventors, patents, and notable applications. A direct conversion receiver (also known as a "zero-IF receiver") represents the simplest type of radio architecture. It was first conceptualized in the early 20th century as a way to simplify radio designs by eliminating the intermediate frequency (IF) stage...

Taming Transients

Taming Transients, July 1963 Electronics World - RF CafeDealing with the problem of lightning strikes was of concern long before electronic equipment needed to be protected from its effects. Fires that were the result of lightning have always been a problem in nature, but they were really catastrophic to civilization once cities crowded with close-quartered wooden buildings became the norm. Benjamin Franklin observed that when the many lightning-induced fires of Philadelphia were sparked (pun intended), it was almost always the tallest structures in the area that were hit. Those fire often spread to neighboring buildings and burned down entire city blocks. It was a devastating and frequency...

Next-Gen Electronics Fail at Lower Temps

How Next-Gen Electronics Fail at Lower Temperatures - RF Cafe"By observing spintronic magnetic tunnel junctions in real-time, researchers found these devices fail at unexpectedly low temperatures, offering valuable insights for improving future electronic designs. Next-Generation Electronics Degradation A new study led by researchers at the University of Minnesota Twin Cities is providing new insights into how next-generation electronics, including memory components in computers, breakdown or degrade over time. Understanding the reasons for degradation could help improve efficiency of data storage solutions. The research is published in ACS Nano, a peer-reviewed scientific journal and is featured on the cover..."

Arthur C. Clarke: A Biography

Arthur C. Clarke: A Biography - RF CafeArthur C. Clarke's writings and contributions to science are vast and influential, intertwining his imaginative narratives with profound scientific concepts. Clarke is credited with proposing the idea of geostationary satellites in a paper he published in the October 1945 issue of Wireless World magazine. Titled "Extra-Terrestrial Relays: Can Rocket Stations Give Worldwide Radio Coverage?," he described the concept of using a network of geostationary satellites to provide global radio coverage. Geostationary satellites are satellites that orbit the Earth at the same rate as the Earth rotates, so they appear to stay in the same place in the sky relative to a fixed point on the Earth's surface. This makes them ideal for telecommunications and broadcasting, as they can provide constant coverage of a particular area without the need for multiple satellites or complicated ground infrastructure...

What's Your EQ?

What's Your EQ?, July 1961 Radio-Electronics - RF CafeHere we go with three new "What's Your EQ?" challenges from the July 1961 issue of Radio-Electronics magazine. Readers submit the problems, which typically involve creating a circuit to perform a specified function, or determining how a given circuit works. The first of these is more of a puzzle, since the author shows you how to go about arriving at the answer. Since incandescent light bulbs are not overly familiar to a lot of people these days, it might be to the advantage of pre-Millennials who grew up using them and are acquainted with their properties. The second is an old-fashioned Black Box challenge that some readers will solve without much...

HAPS Aircraft for Stratospheric Comms

SoftBank Trials HAPS Aircraft for Stratospheric Communications - RF Cafe"Japanese operator SoftBank announced that the Sunglaider, its large-scale solar-powered uncrewed aircraft system (UAS) designed for High Altitude Platform Station (HAPS) stratospheric telecommunications, was utilized in a field trial conducted by AeroVironment and the U.S. DoD in New Mexico, the U.S. During the trial, carried out in early August, Sunglider succeeded in achieving stratospheric flight, the Japanese operator said. With a wingspan of 78 meters and the capability to carry payloads weighing up to 75kg, the Sunglider is larger than other publicly announced HAPS UAS..."

Electronics Diagram Quiz

Electronics Diagram Quiz, August 1966 Popular Electronics - RF CafeMonday (any day, for that matter) is a good day for Carl and Jerry stories, Mac's Electronics Service Shop sagas, Hobnobbing with Harbaugh, electronics-themed comics, electronics quizzes, and other forms of nerd entertainment. Here is another of Robert P. Balin's great challenges titled, "Diagram Quiz," this one from a 1966 issue of Popular Electronics magazine. Most RF Cafe visitors will easily identify eight or nine of the ten diagrams. Relatively few will be familiar with the Rieke diagram (hint: power amplifier designers will know about it). The Biasing diagram is a bit misnamed IMHO, and could cause confusion...

Anatech Has 3 New Filter Models for October

Anatech Electronics - 3 New Filter Models for October 2024 - RF CafeAnatech 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 ceramic bandpass filters have been announced for October 2024 - a 2275 MHz center frequency filter with a bandwidth of 250 MHz, a 2275 MHz center frequency filter with a bandwidth of 250 MHz, and a 6245 MHz center frequency filter with a bandwidth of 360 MHz. Custom RF power filter and directional couplers designs can be designed and produced with required connector types when a standard cannot be found, or the requirements are such that a custom approach is necessary.

The Operational Amplifier

The Operational Amplifier, July 1963 Electronics World - RF CafeWhen you read this 1963 Electronics World magazine article's title, I doubt you immediately assumed it would be about a vacuum tube circuit, or even one that uses discrete transistors to implement the circuit. Rather you most likely though it would be about an integrated circuit (IC). Operational amplifiers (opamp) are building blocks characterized (ideally) by their infinite input impedance, zero output impedance, infinite open-loop bandwidth and gain, zero input offset voltage, amongst other defined parameters. The first commercially produced integrated circuit (IC) opamp came to market in 1964 via Fairchild Semiconductor (the µA702, brainchild of Bob Widlar)...

The Nickel-Cadmium (NiCad) Battery

Nickel-Cadmium (NiCad) Battery (ChatGPT-generated content) - RF CafeNickel-cadmium (NiCad) batteries have a long and significant history in energy storage, with their invention attributed to Swedish engineer Waldemar Jungner in 1899. Jungner's work laid the foundation for an electrochemical power source based on nickel oxide hydroxide and cadmium, leading to the development of the rechargeable NiCad battery. It was a pioneering breakthrough because it represented one of the earliest forms of rechargeable energy storage systems. This battery technology found widespread use in various industries due to its robust performance and ability to be recharged multiple times. At its core, the chemistry of NiCad batteries involves the reaction between cadmium (the negative electrode) and nickel oxide hydroxide (the positive electrode), with potassium hydroxide as the electrolyte. During...

Electronics-Themed Comics

Electronics-Themed Comics, September 1969 Electronics World - RF CafeThese two tech-themed comics from the September 1969 issue of Electronics World magazine are pretty good. I especially like the one where the guy's wife entered his printed circuit board layout in an art contest. PCBs were just starting to gain momentum in production electronics as they replaced the old point-to-point wiring method. Also popular in that era was high fidelity stereo equipment. Owning a system with speakers that operated from 1 Hz through 30 to 40 kHz was major evidence of an audiophile's technical savvy, even though the human ear con only detect frequencies in the 30 Hz to 20 kHz range. Dogs can hear frequencies up into the 45 kHz range. Porpoises can hear up to 150 kHz. A ferret can hear from 16 Hz...

NextGen Thermal Performance Testing

Next Generation Thermal Performance Testing - RF CafeTotalTemp Technologies offers advanced and innovative methods for meeting and optimizing your thermal testing requirements. We specialize in benchtop thermal testing because small batches are typically the most cost-effective approach. We offer heat transfer by conduction with thermal platforms, forced convection as in traditional temperature chambers, combined systems, and thermal vacuum for Space Simulation. Thermal testing of Traveling Wave Tube Amplifiers and other devices with dramatically uneven power dissipation can easily be achieved with a dual zone thermal platform. Managing the heat produced by the electron gun side allows for the RF outputs side to be tested at various required temperatures. The Dual Zone Thermal Platforms allows the user to maintain safe controlling...

Engineering & Tech Headlines <Archives>

• Ham Radio Serving Southeast U.S. Recovery Efforts

• Radio "A Godsend for So Many" in Helene's Aftermath

• Estate Planning for Hams

• Intel's Woes Damaging U.S. Chip Indpendence

• Is Gen-Z Low Car Ownership a Threat to Radio? (they can't afford cars due to massive inflation - not because they don't want a car)

AMRAD: A Brief Overview and Historical Context

AMRAD: A Brief Overview and Historical Context - RF CafeAmrad, American Radio & Research Corporation, was based in Medford Hillside, Massachusetts and was founded in 1915 with funds from J. Pierpont Morgan. The company's first manager, Harold James Power, was an amateur radio enthusiast and built a research laboratory. In 1916, Amrad made its first broadcast to J. Pierpont Morgan Jr., who was aboard the ocean liner "Philadelphia." Amrad received orders for military radio equipment during World War I, but discontinued these orders after the war ended. To keep the company afloat, Amrad produced items such as electric egg beaters and cigar lighters. In 1919, Amrad was awarded a contract to make 400 SE1420 receivers, and it began advertising components for amateur radio enthusiasts...

Which Dry Battery for You?

Which Dry Battery for You?, June 1963 Radio-Electronics - RF CafeThis "Which Dry Battery for You" article is a follow-on from the previous month's "Dry Cell Battery Types" in Radio-Electronics magazine. It was a time long before the dominance of rechargeable lithium batteries. In 1963, battery-powered devices were nowhere near as widespread and diverse as they are nowadays. Hand tools like drills, saws, routers, planers, and screwdrivers got their power either from a wall outlet or the user's arm and hand muscles. Lawn mowers, grass and hedge trimmers, chain saws, and snow blowers were powered mostly by gasoline, although some models plugged into the wall. Those devices which did use batteries most often had no built-in...

Light Waves to Logic Optical Computing

Light Waves to Logic Optical Computing - RF Cafe"Researchers have developed a new architecture for optical computing called diffraction casting, offering power-efficient processing by using light waves. This method promises better integration and flexibility for high-performance computing tasks and could be used in fields like AI and machine learning. As artificial intelligence and other complex applications demand ever more powerful and energy-intensive computers, optical computing emerges as a promising solution to enhance speed and power efficiency. However, its practical application has faced numerous challenges..."

AEC: A Brief Overview and Historical Context

Atomic Energy Commission, AEC: A Brief Overview and Historical Context (ChatGPT-generated content) - RF CafeThe Atomic Energy Commission (AEC) was established in 1946 as a result of the Atomic Energy Act, signed into law by President Harry S. Truman. This legislative decision marked the United States' formal entry into managing and controlling atomic energy, a rapidly advancing field that had been essential in concluding World War II through the development and use of nuclear weapons. The AEC was conceived to handle not only military applications of atomic energy but also to develop peaceful uses, such as energy production, medical research, and industrial applications. The creation of the AEC emerged from the Manhattan Project, the secret wartime effort to develop atomic bombs. The Manhattan Project brought together prominent scientists like J. Robert Oppenheimer, Enrico Fermi, and Niels Bohr. After the war, however, the question arose...

Empower RF 8 kW, X-Band Pulsed HPA

Empower RF Systems Model 2221, 8 kW, X-Band Pulsed HPA - RF CafeEmpower RF Systems, the technology leading provider of high-performance RF amplifiers, is proud to announce the launch of the Model 2221 X-Band Pulsed High Power Amplifier. The Empower RF 2221 amplifier operates in the 9-10 GHz X-band, delivering an impressive 8000 W peak output power with long and short pulse widths. Its applications encompass radar systems, electronic warfare, HPM research, and electromagnetics effects testing. With a rugged, modular design, the 2221 offers a reliable, high-performance solution for applications demanding significant X-band power. Key Features and Specifications The model 2221 amplifier operates in the 9-10 GHz X-band frequency range, delivering an impressive 8 kW of peak pulsed output power...

The Fraudulent Technician - A Minority

The Fraudulent Technician - A Minority, May 1964 Electronics World - RF CafeAlthough not in the title as it used to be, this 1964 Electronics World magazine piece by John T. Frye is a "Mac's Service Shop" story. If Mac and Barney are the stars of the saga, then it can be none other. The story is about how the misdeeds of a few dishonest operators can taint the reputation of an entire industry - nothing new there. Barney is telling Mac about a "sting" ploy pulled by a consumer protection group whereby TV sets with a specific easy-to-troubleshoot problem introduced to see how repair technicians from a suspect company would bill the service. I'll not spoil the ending for you; however, a comment mentioned that $10 would have been a reasonable price for a house call that included the fix. According to the BLS's inflation calculator, $10 in 1964 was the equivalent of about $102 in 2024...

Unexplored Electron Gap

Unexplored Electron Gap, March 1962 Radio-Electronics - RF CafeEver the futurist, in 1962 Radio-Electronics magazine editor Hugo Gernsback was making the case for occupying millimeter- and submillimeter-wave bands. In fact, he first proposed the concept back in 1959. He refers to it as "gap between the infrared (IR) and radio regions." IR is generally understood to include wavelengths from around 750 nm (400 THz) to 1 mm (300 GHz). Gernsback cites work done by Professor Gwyn O. Jones, of Queen Mary College of the University of London, with the claim that among other advantages of millimeter-wave (mm-wave) is an ability to penetrate certain wavelength "windows" in the atmosphere where lower frequencies do not propagate efficiently, more "channels" of communications can be accommodated, smaller antennas could be used, and narrower focused transmission beams possible...

Werbel 10-Way Splitter for DC-7.2 GHz

Werbel Microwave 10-Way Resistive Power Splitter for DC to 7.2 GHz - RF CafeWerbel Microwave's WMRD10-7.2-S is a 10-way resistive splitter that covers up 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, test and measurement, and military radio. Its small size makes it easy to integrate into compact systems. Designed, assembled, and tested in the USA.

Hugo Gernsback: A Biography

Hugo Gernsback: A Biography - RF CafeHugo Gernsback, often heralded as the "Father of Science Fiction," was an extraordinary figure whose influence extended beyond the realm of speculative literature into the world of electronics, radio communication, and futurism. His life, inventions, and publications shaped not only popular science but also the practical development of radio and electronics, making him a pivotal figure in early 20th-century technological advancements. Gernsback was born Hugo Gernsbacher on August 16, 1884, in Luxembourg City, Luxembourg, to a wealthy family. His father, Moritz Gernsbacher, was a winemaker and merchant, while his mother, Bertha, came from a prominent local family. Hugo had several siblings, though details of his early family life remain somewhat obscure. From a young age, Hugo showed a strong interest in science and technology, particularly in electricity and wireless communication. He attended local schools in Luxembourg and later pursued formal education at the Technikum in Bingen, Germany...

CostQuest Gerrymanders for BEAD Biddable Locations

CostQuest Gerrymanders for BEAD Biddable Locations - RF CafeThese government programs take forever to implement, then a major portion of the money gets wasted in bureaucracies, payoffs, and misappropriations (e.g., 8 EV charging stations after spending $7.5B). "If you know CostQuest at all you probably think of it as the company that the FCC hired to clean up and refine its national broadband map. But the company is also working with state broadband offices on their Broadband Equity, Access and Deployment (BEAD) programs. To give a little background, CostQuest works with the FCC on its national broadband map. But it was also hired, separately, by the National Telecommunications and Information Administration (NTIA) to work with states..."

Carl & Jerry: Two Detectors

Carl & Jerry: Two Detectors, February 1955 Popular Electronics - RF CafeListen to the Podcast! Just in time for Halloween, John T. Frye's teenage sleuths Carl & Jerry unexpectedly recorded a late-night conversation between two men where they plot how to dispose of the "body" when death occurred as a result of prolonged choking. Employing their trademark technical prowess and scheming ability, the pair sets a trap for the perpetrators and dutifully summon the authorities as they complete their nefarious act of the night before. Halloween comes into play because the recordings were made for use in creating sound effects during the reading of Edgar Allen Poe's "The Pit and the Pendulum" and "The Cask of Amontillado." This story, which appeared in a 1955 issue of Popular Electronics magazine, is a little dark compared to a typical story...

America's Next Great Industry - Television - is Ready

America's Next Great Industry - Television - is Ready, January 1945 Radio News - RF CafeBy 1945 everyone of importance in the electronics industry was blowing the figurative horn of television. The country would transform from "a chicken in every pot" to "a TV in every living room" (OK, I just made that up). The NTSC (National Television System Committee) had set the standards for transmission, but hardware implementation was by no means agreed upon. If my memory is correct, there were still some manufacturers clinging to the mechanical spinning disc with a projection screen rather than using electronic circuits and a CRT (cathode ray tube). Entire industries - not only electronics - were bursting at the seams in anticipation of the war ending and being allowed to release all the pent up knowledge and inventions developed during the years working toward the defeat of Axis powers across the globe being applied to creature comforts for the civilian marketplace. Television, with its countless dependents and dependencies, truly changed the planet. Some say for the better, others say for the worse...

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 ...

Stratovision

Stratovision, October 1945 Radio-Craft - RF CafeBefore comprehensive coaxial and optical cable or even microwave relay networks were available for commercial use, an experimental aircraft-based system was tested for broadcasting educational television and other messaging data. The "Stratovision" platform essentially provided a couple 20,000-foot-high antennas with a footprint covering hundreds of miles. This 1945 Radio-Craft magazine article entitled ,"Stratovision" was one of the earliest to report on plans to provide a coast-to-coast nationwide matrix of coverage as shown in the accompanying illustration. Two outfitted airplanes would be in the air within each region at all times to ensure redundancy and high quality service. Boeing B-29 Superfortress airplanes (the Enola Gay was a B-29) were used at least in part because they provided a human-friendly environment at high altitudes for long period of time...

Mathematical Puzzles, 1976 Old Farmer's Almanac

Mathematical Puzzles, 1976 Old Farmer's Almanac - RF Cafe1976 is the year I was emancipated (aka graduated) from high school, and this issue of The Old Farmer's Almanac (OFA) happens to be from that year. For as long as I can remember, the OFA has included a set of Mathematical Puzzles in its annual publication. They range in difficulty from 1 (very easy) to 5 (sometimes quite difficult). Having been a faithful buyer and reader of the OFA for as long as I can remember, I have spent many hours toiling with some of the more challenging examples. In fact, there were a lot which I never did figure out and needed to look up the answers in the back (come to think of it, I experienced the same dilemma with my college engineering textbooks). Because quite a few of the Mathematical Puzzles are worthy of an engineer's cerebration, contemplation, and deliberation, all I have will be eventually posted here on RF Cafe. Enjoy!

Electronics Theme Crossword Puzzle for December 13th

Electronics Theme Crossword Puzzle for December 13, 2020 - RF CafeFor 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. This December 13th Electronics Theme crossword puzzle, as always, contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

RCA Victor Model 102 Receiver Radio Service Data Sheet

RCA Victor Model 102 4-Tube A.C.-D.C. T.R.F. Receiver Radio Service Data Sheet, January 1935 Radio-Craft - RF CafeRadio Service Data Sheets were published by various electronics trade magazines back in the early to middle decades of the last century. SAMS Photofact document sets were published on just about every appliance made, and those had much more detail than these briefs. However, for the low-budget repair shop or the do-it-yourselfer, the Radio Service Data Sheets were a godsend. I have been scanning, cleaning up, and posting all the ones I find in my vintage electronics magazine collection. See a complete list at the bottom. Many fine examples of restored vintage radios can be found on the Internet. A restored example of the RCA Victor Model 102 s appears on the RadioMuseum.com website...

February 1947 Radio-Craft Electronics-Themed Comics

Electronics-Themed Comics, February 1947 Radio-Craft - RF CafeSome of the best electronics-themed comics appearing in these vintage magazines are the "Radio Term Illustrated" type - IMHO, anyway. Most of them are ideas suggested by readers, then illustrators like Frank Beaven created the visuals. The comic on page 79 is pretty self-explanatory, but the page 66 pun might need some explanation to those unfamiliar with vacuum tube circuits. The "B" battery is a term created by Mr. Lee de Forest as a designation for the second battery required for the plate bias (the "B") of his Audio tube. Typical voltages were 45 volts, 67½ volts, and 90 volts. If that doesn't completely clear up the pun, then you also need to know that an alternative definition of battery which is a military artillery installation...

How to Break the 10-Words-Per-Minute Code Barrier

How to Break the 10-Words-Per-Minute Code Barrier, July 1974 Popular Electronics - RF CafeWhen you think about it, the speed at which a human being is able to accurately copy Morse code is limited by the same kinds of processes that limit the speed at which binary data can be sent between electronic transceivers (modems). Noise introduced into the signal at both the transmitting and receiving ends or in the transmission path connecting the two, degrades the ability of the receiver (electronic and human) to discern between a "1" and a "0." It can take the form of electrical or audio interference and distortion. Phase noise in the electronic realm is sort of the equivalent of an irregular sending human hand that cannot maintain equal dwell times for dits and dahs, thus making the recognition of characters error-prone. The operational speed of circuitry on an electronic assembly can also limit the speed at which Morse code can be copied similar to how a particular person's gray matter can limit his comprehension speed...

Mac's Service Shop: Salvaging Dunked Radios

Mac's Service Shop: Salvaging Dunked Radios, July 1972 Popular Electronics - RF CafeThis 1970s-era Mac's Service Shop story made me think about all the cellphones today being dunked in toilets, swimming pools, lakes, and washing machines. Of course back in Mac''s day not everyone was walking around with an electronic device tucked into his or her pocket waiting for its absentminded owner to bend over or drop his/her drawers. At the time, far more wallets made the dive than transistor radios. I won't bother linking to any articles about how to best dry your dunked phone because there are hundreds - nay, thousands - of them out there. They contradict each other about which absorbent materials to use...

RF & Electronics Stencils for Visio

RF & Electronics stencils for Visio r4 - RF CafeWith 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...

Theory and Application of U.H.F.

Theory and Application of U.H.F., June 1945 Radio News - RF CafeThis is the final installment of an 11-part series in Radio News magazine entitled "Theory and Application of U.H.F.," written by Milton Kiver. It spanned from December 1943 to June 1945. Topics included basic electrical, magnetic, and electromagnetic theory, cavity resonators as tuning units of klystron and magnetron oscillators, waveguide, free space propagation, high frequency amplifiers, transmission lines, and coupling energy to/from cavity resonators. As the list suggests, there was a great concentration on field theory. Being that the Radio News readership covered a broad range of experience and education, Mr. Kiver went light on use of equations and heavy on use of diagrams, charts, and textual descriptions. Everything described throughout the series is as valid and applicable today as it was 75 years...

Generators, Electricity - Basic Navy Training Courses

NAVPERS 10622, Chapter 14 - Generators, Electricity - Basic Navy Training Courses - RF CafeIn keeping with a very common practice of using water flowing through a garden hose as a teaching aid analogy for newcomers, the title of this chapter of the NAVPER 10622 Basic Navy Training Courses, "Generators - Electrical Pumps," is likening electrical generators to water pumps. It is an apt analogy, but whereas a water pump can cause water pressure and flow of a physical substance already on-hand, electrical "pumps," aka generators, literally creates its "flow" from thin air (even a vacuum with no air). An electrical generator exploits the phenomenon discovered by (or at least credited to) Michael Faraday whereby a conductor moving through a magnetic field - or a magnetic field moving past a conductor ...

RF & Microwave Theme Crossword Puzzle for December 5th

RF & Microwave Theme Crossword Puzzle for December 5th, 2021 - RF CafeThis RF & Microwave themed crossword puzzle for December 5th contains only clues and words are directly to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other science subjects. As always, this crossword contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

How to Target RFCafe.com for Your Google Ads

Google AdSense - it makes good sense - <em>RF Cafe</em>One aspect of advertising on the RF Cafe website I have not covered is using Google AdSense. The reason is that I never took the time to explore how - or even whether it is possible - to target a specific website for displaying your banner ads. A couple display opportunities have always been provided for Google Ads to display, but the vast majority of advertising on RF Cafe is done via private advertisers. That is, companies deal with me directly and I handle inserting their banner ads into the html page code that randomly selects and displays them. My advertising scheme is what the industry refers to as a "Tenancy Campaign," whereby a flat price per month is paid regardless of number of impressions or clicks. It is the simplest format and has seemed to work well for many companies. With nearly 4 million pageviews per year for RFCafe.com, the average impression rate per banner ad is about 225,000k per year (in eight locations on each page, with >17k pages)...

Bell Telephone Laboratories Salutes 3 New Nobel Prize Winners

Bell Telephone Laboratories Salutes Three New Nobel Prize Winners, February 1957 Radio & Television News - RF CafeAnyone visiting RF Cafe (other than by accident) almost certainly knows of Drs. Bardeen, Brattain and Shockley fame for their transistor invention while jointly working at the Bell Telephone Laboratories. The trio shared The Nobel Prize in Physics in 1956. Bell was so proud of their employees' efforts that they ran full page advertisements to boast of the accomplishment. This one appeared in the February 1957 edition of Radio & Television News. Alas, Ma Bell's moment of glory was a bit diminished by needing to add a footnote admitting that Drs. Bardeen and Shockley no longer work there. Note that while the ad says the transistor was announced in 1948, the first demonstration to Bell managers was in December of 1947...

Radio Data Sheet Zenith Model 8H032

Radio Data Sheet Zenith Models 8H032, 8H033, 8H050, 8H052, 8H061, January 1947 Radio-Craft - RF CafeHere is the Radio Data Sheet for Zenith radio models 8H032, 8H033, 8H050, 8H052, 8H061 as published in a 1947 issue of Radio-Craft magazine. Some of the electronics magazines used to include this type of high level documentation so that hobbyists and even service shops with budgets too small to afford cabinets full of SAMS data packets could work on the radios. Most of the radio manufacturers would not even sell factory-prepared documentation to anyone who was not an "authorized" service center. The RadioMuseum website has nice examples of restored versions of both the Zenith 8H032 and the Zenith 8H034 tabletop radios. The electronics are similar but the chassis designs are completely different. They sport three bands: the 540-1620 kHz AM band, the pre-WWII 42-48.5 MHz FM band, and the current 88-108 MHz FM band...

Housewives and Television

Housewives and Television, October 1947 Radio-Craft - RF CafeContrary to the scenario presented in this light-hearted mockery of housewives attempting to assemble some electronics kits, there were actually many women during the height of the radio and television age who were quite adept at handling soldering irons and test equipment. In fact, the case could be made that, given the 1947 appearance of this "Housewives and Television" piece in Radio-Craft magazine, women of the post-wartime industrial period were probably the most experienced and adept assemblers of electronics equipment. After all, it was Rosie the Riveter who built airplanes, ships, and tanks while Sally the Solderer built the bulk of the tens of thousands of radios, radars, sonars, medical and test instruments, vacuum tubes, amplifiers, and other electronics while the brothers...

The Antenna Specialists Co. Advertisement

The Antenna Specialists Co. Ad, July 1966 Popular Electronics - RF CafeHere's a gimmick that never really caught on. In the 1960's, Antenna Specialists promoted their Model M-148 Co-Ax Omni Antenna "with visual RF indicator." That indicator was a neon light bulb at the tip which lit up when the transmitter was keyed on. Not only would this novel feature let you know when your transmitter was broadcasting, but it would also "guide mobiles visually to your 10-20." OK, maybe at night, but it certainly wouldn't have been bright enough during the day to even see. Alas, the public evidently didn't impress the buying public as much as it did the designers. Maybe it had something to do with...

Paul Harvey Honors Ham Radio Operators

Paul Harvey Honors Ham Radio Operators - RF Cafe Smorgasbord"Hello Americans, This is Paul Harvey..." Radio legend Paul Harvey produced and performed a daily show that featured news, commercials, and commentary. For nearly 75 years, dedicated listeners looked forward to his show on the local AM radio stations - especially The Rest of the Story. Scores of wars, natural disasters, crises, deaths, scientific advances, miracles, and acts of human kindness were commented upon in Mr. Harvey's unique delivery style. On March 19, 2003, Mr. Harvey did a pitch for the role of Amateur Radio operators in emergency response roles. The mention was the second item on "page four" of his Paul Harvey Noon News and Comment program. "America's quiet warriors are the legion of ham radio operators, 700,000 of them, who are always at ready for backup duty ..."

How Audions Were Built

How Audions Were Built, January 1947 Radio-Craft - RF CafeIf you have never read the story of Lee de Forest's journey from initial experiments to finally achieving success with his amplifying vacuum tube, the Audion, then you might want to take a few minutes to look over this article. It was published in a 1947 issue of Radio-Craft magazine as part of the 40th anniversary of the invention that changed the electronics world. With so many other things which are nowadays very commonplace, we tend to not think about or appreciate the ingenuity and effort that went into them. It is one thing to make incremental improvements in an existing technology, but to conceive of and created an entirely new realm of science is quite another. As with Albert Einstein's relativity and Robert Goddard's liquid-fueled rockets, and the Wright brothers' powered aeroplane...

Are You a "Television Looker?"

QST Looks at Television - 1944, January 1945 QST - RF CafeDid you know that you are likely a TLV? That's right, a Television Looker. The modern equivalent is CP - Couch Potato. In the early years of television, TLVs were as fascinated with the device itself and the technology as they were with the information being displayed. As this story tells, Hams were involved in TV transmission (ATV) early on. I did not know that amateur television was banned during World War II. During WWII, all amateur radio operations were suspended with the exception of those authorized to continue under the Radio Amateur Civil Emergency Service (RACES)...

The Vanishing Circuit Designer

Texas Instruments Type 502 Integrated Circuits - RF CafeHow is this for a prescient prediction from the early 1960s? "As a result of modular and integrated circuitry techniques, all future circuit design work, regardless of degree, will become the responsibility of the component manufacturer instead of the equipment producer." Texas Instruments' (TI) Jack Kilby is credited with designing the first integrated circuit in 1958. The first commercial IC, Ti's Type 502 flip-flop, had just hit the market in early 1960, and already pundits were prognosticating and ruing the disappearance of circuit designers. Maybe it was concerns over job security that they seem to favor forever building every circuit from discrete transistors, resistors, capacitors, and inductors. Rumor has it they also lobbied for the perpetual existence of the buggy whip and horse-drawn farrow industries ...

Radio Theme Crossword Puzzle for June 12th

Radio Theme Crossword Puzzle for June 12th, 2021 - RF CafeThis Radio Theme Crossword Puzzle for June 13 has many words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects. Also, it contains at least five (5) instances of this puzzle's theme word. As always, this crossword contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

After Class: Some Facts on Quartz Crystals

After Class: Special Information on Radio - Some Facts on Quartz Crystals, TV, Radar, and Nucleonics, January 1957 Popular Electronics - RF CafeAccording to a 2001 paper published by the National Institute of Standards and Technology (NIST, formerly National Bureau of Standards, NBS), "The end of the era of quartz frequency standards began in 1949 with the development at NBS of the world's first atomic frequency standard based on an ammonia absorption line at 23.87 GHz." Further, "The Bureau supported work on both technologies for the next decade, but the rapid advances in the accuracy of atomic frequency standards could not be matched by quartz devices, and the work on quartz frequency standards was stopped in 1959." This article from a 1957 edition of Popular Electronics claims that the "master of all master-clocks" resided at the U.S. Naval Observatory at the time - not quite accurate from what my research indicates ...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe 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...

New Standards for TV Antennas

New Standards for TV Antennas, November 1954 Radio & Television News - RF CafeThe RETMA referenced in this 1954 Radio & Television News magazine article entitled "New Standards for TV Antennas" was commonly known back in the day, but not many would recognize it nowadays. RETMA, founded in 1953 at the dawn of the commercial television age, was the Radio Electron[ics] Television Manufacturing Association. It set standards for electronics components like resistors (e.g., the 1%, 2%, 5%, 10% series), capacitors, inductors, equipment racks, and antennas. After many name iterations, what began as the Radio Manufacturers Association (RMA), it changed to RETMA in 1953, then to Electronic Industries Association (EIA, well-known for its 19" rack standards) in 1957, and today it is known as the Consumer Technology Association (CTA). The cost of letterhead and promotional material changes over the years must have been enormous ;-) Tracing the full history is difficult, but between Wikipedia and the JEDEC websites you can get a pretty good picture. The "Antenna Section" spoken of here is the area of the RETMA manual pertaining to antennas...

The Transistor in Industry

The Transistor in Industry, May 1956 Radio & Television News - RF CafeIf you want to know what was really going on at some point in the past, there is usually nothing more reliable than reading a print story or advertisement from the era. That way you're getting the news "straight from the horse's mouth," so to speak, rather than being interpreted or filtered by some unassociated source. This report on "The Transistor in Industry" was written in 1956 by Mr. Frank Durat, a product manager at Raytheon, at a time when transistors were first making inroads for replacing the venerable vacuum tube (valve) which had launched and propelled the electronics industry since 1908 when Lee de Forest introduced the triode Audion amplifier. Germanium and silicon were the semiconductor base crystals du jour, and achieving the requisite purity was a primary concern for advancing the state of the art for higher frequencies, power handling, and circuit density (for integrated circuits)...

May 27 RF Cafe Engineering Crossword Puzzle w/Weekly Headlines

RF Cafe Engineering Crossword Puzzle w/Weekly Headlines May 27, 2018At least 10 clues with an asterisk (*) in this technology-themed crossword puzzle are pulled from this past week's (5/21 - 5/25) "Tech Industry Headlines" column on the RF Cafe homepage. For the sake of all the avid cruciverbalists amongst us, each week I create a new technology-themed crossword puzzle using only words from my custom-created 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, see someone or something in the exclusion list who or that is directly related to this puzzle's theme, such as Hedy Lamar...

The Maser & Sugar Scoop Antenna: Receiver for Signals from Space

The Maser & Sugar Scoop Antenna: Receiver for Signals from Space, November 1960 Electronics World - RF CafeWhen really good researchers set out to write books on history, they do not simply cull information from the publications of fellow contemporary authors; instead, they look for sources that were published during or around the time of the subject being covered. Doing so helps minimize the possibility that inaccuracies have crept into the knowledge pool and that information other authors might have either deemed insignificant or have missed can be recovered. With a bit of luck, sources are discovered that have never been used before. That is part of my motivation for going to the trouble of buying these vintage magazines and posting articles like this one which reports on early maser developments. It delves fairly deeply into the solid state physics of rare earth minerals that some of the first masers and lasers relied upon to function, including energy band diagrams and cryogenics. If the "sugar scoop" antenna looks familiar, it might be due to its rising to fame...

Copper Mountain Technologies (VNA) - RF Cafe
RF Cascade Workbook 2018 by RF Cafe

KR Electronics (RF Filters) - RF Cafe

Werbel Microwave (power dividers, couplers)