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Amplifier Solutions Corporation (ASC) - RF Cafe

Exodus AMP20026 2–6 GHz, UWB, 200 W SSPA

Exodus AMP20026 2.0–6.0 GHz, Ultra-Wideband 200 W 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. Exodus' AMP20026 is a rugged 2.0 to 6.0 GHz solid state amplifier delivering a minimum of 200 W with clean, stable 53 dB gain. It offers excellent gain flatness, a 20 dB control range, and full protection circuitry. Built for EMI/RFI, lab, CW/pulse, and EW environments, it delivers instantaneous bandwidth, superb reliability, rack mount configuration...

The Junction Transistor

The Junction Transistor, April 1952 Radio & Television News - RF CafeIn April of 1952 when this article appeared in Radio & Television News magazine, the bipolar junction transistor (BJT) had only made it out of the experimental laboratory of Messrs. Bardeen, Shockley, and Brattain at Bell Labs a mere three years earlier in December of 1948. It did not take long for commercial production to begin. Along with being a great primer for anyone new to transistors, herein is also some background on how the now ubiquitous BJT schematic symbol was created. Interestingly, only Dr. William Shockley is mentioned, making me wonder whether the contributions of Dr. John Bardeen, and Dr. Walter H. Brattain was not widely publicized early on. Not to worry, though, because all three were duly...

Mac's Service Shop: No Hands, No Head

Mac's Service Shop: No Hands, No Head, March 1959 Radio & TV News Article - RF CafeMac's Service Shop captures here a moment of technological transition in 1961 where a new "Loud-speaking Telephone" impresses his right-hand man, Barney. The device utilizes vacuum-tube amplifiers and a bulky external control box to allow hands-free communication, enabling Mac to work while handling customer inquiries. Mac, ever the mentor, contrasts this tube-based unit with the emerging technology of transistorized speakerphones, which eliminate the need for external control boxes, external power supplies, and warm-up times. The 1961 "Loud-speaking" setup, occupying significant space under a workbench, has been completely replaced by modern smartphones and integrated VoIP systems...

RF & Microwave Engineering Crossword for January 3, 2016

RF & Microwave Engineering Crossword Puzzle for January 3, 2016 - RF CafeAs with all RF Cafe crossword puzzles, this one uses only words pertaining to engineering, science, mathematics, mechanics, chemistry, astronomy, etc. As always, this crossword puzzle 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!

Microwave Klystron Oscillators

Microwave Klystron Oscillators, April 1952 Radio & Television News - RF CafeWEDW CH 49 Transmitter Klystron (Joe Molon, KA1PPV) - RF CafeThe microwave klystron was invented in 1937 by brothers Russell and Sigurd Varian. If you have been in the microwave design business for a couple decades, you undoubtedly recognize the company name of Varian Associates, especially if you worked in the aerospace or defense electronics business. There is a video on YouTube of a segment on Varian done sometime around 1990 by Walter Cronkite. There is also a historical piece on Varian Associates on the Communications & Power Industries website. This circa 1952 article covers the fundamentals of klystron operation and reports on the increasing use of klystrons in high frequency application - including by amateur radio operators exploring...

Werbel 2-Way Resistive Splitter for DC-7.2 GHz

Werbel Microwave WMRD02-7.2-S Resistive 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, and has quickly grown into a major designer and manufacturer with volume production capacities. The WMRD02-7.2-S is a resistive splitter that covers up to 7.2 GHz with ultra-wide bandwidth. This design is useful when there are many low power signals within a wide spectrum. By design, the nominal insertion loss and isolation is 6 dB, hence it is often referred to as a "6 dB splitter." Its small size makes it easy to integrate into compact systems. Designed, assembled, and tested in the USA. "No Worries with Werbel!"

The Yagi Antenna

The Yagi Antenna, October 1951 Radio & Television News - RF CafeContributors to the Wikipedia article on the Yagi–Uda antenna credit Japanese professor Shintaro Uda primarily for the antenna's development, with Hidetsugu Yagi having played a "lesser role." Other sources assign the primary role to Yagi. Regardless, history - and this article's author, rightly or wrongly, has decreed that this highly popular design be referred to commonly as the Yagi antenna and not the Uda antenna. I don't recall seeing advertisements for "'Uda" television or amateur radio antennas. Harold Harris, of Channel Master Corporation, does a nice job explaining the fundamentals of the Yagi antenna. Another Yagi article appeared in the October 1952 issue of QST magazine...

Many Thanks to dB Control for Support!

dB Control - RF CafeEstablished in 1990, dB Control supplies mission-critical, often sole-source, products worldwide to military organizations, as well as to major defense contractors and commercial manufacturers. dB Control designs and manufactures high-power TWT amplifiers, microwave power modules, transmitters, high- and low-voltage power supplies, and modulators for radar, ECM, and data link applications. Modularity enables rapid configuration of custom products for a variety of platforms, including ground-based and high-altitude military manned and unmanned aircraft. Custom RF sources and receivers, components and integrated microwave subsystems as well as precision electromechanical switches. dB Control also offers specialized contract manufacturing and repair depot services.

99.99999999% Pure Germanium

99.99999999% Pure Germanium, September 1959 Radio-Electronics - RF CafeThe production of high-performance transistors necessitated new methods to achieve extreme purity levels, far beyond standard industrial capabilities. To reach the required purity of one part in ten billion, engineers adopted zone melting, a sophisticated technique pioneered by W. G. Pfann. In this process, radio-frequency heating coils melt a narrow zone of a semiconductor rod, which is then moved along the crystal to sweep impurities to one end. Beyond purification, zone melting allows for the precise, uniform introduction of "dopants" like antimony or indium, which are essential for creating p-type and n-type semiconductor characteristics. By refining these methods through continuous processing and floating-zone techniques, manufacturers significantly...

Adson Radio & Electronics Co.

Adson Radio & Electronics Co. Ad, January 1949 Radio & Television News - RF CafeHere's another advertisement that you probably wouldn't see in a contemporary RF / microwave engineering magazine. For that matter you probably wouldn't see it on a contemporary RF / microwave engineering website ... except on RF Cafe where political correctness gets no respect. Adson Radio & Electronics was located on Fulton Street in New York City, just a block from the 911 Memorial. the original building might have been destroyed when the...

How to Make the World's Smallest 3-Tube Radio Set

How to Make the World's Smallest 3-Tube Radio Set, December 1936, Radio-Craft - RF CafeMy first thought when seeing the cover for this edition of Radio-Craft magazine was that it was an April Fools gag, but it turns out the "hat" being worn by the radio receiver's designer is a loop antenna for AM reception. Ya' know, he does look like he could be a suicide bomber. In a way it is the opposite of a tinfoil hat in that this headgear invites electromagnetic energy around the wearer's head rather than shielding it. Back in 1936, being seen in public donning a contraption like this radio would have been akin to Google Glass today - you'd be a superhero to fellow nerds, and just be confirming your otherworldly nerd status to non-nerds...

Building a 1930 Electric Receiver

Building a 1930 Electric Receiver, November 1929, Radio-Craft - RF CafeVreeland Corporation was an early radio manufacturer located in Hoboken, New Jersey, with multiple patents on file for innovative circuits. The Vreeland band selector system mentioned here was originally filed in the U.S. Patent and Trademark Office in August of 1927 and had not been awarded by the time of this November 1929 article in Radio-Craft magazine. In fact, it wasn't until five years later, in 1932, that the patent was finally assigned. The official description reads in part, "The general purpose of the invention is to receive the component frequencies of such a band with such uniformity as to avoid material distortion of the modulated wave, and to exclude frequencies outside of the band which the system is designed to receive. Another purpose of the invention is to provide means for shifting the position of the band...

Bell Labs - Voice of a Guided Missile

Bell Telephone Laboratories - Voice of a Guided Missile, September 1959 Radio-Electronics - RF CafeIn this 1959 Radio-Electronics magazine promo, Bell Telephone Laboratories showcased its advanced radio-inertial guidance system, a technological breakthrough enabling precise long-range missile flight. Developed for the Air Force's Ballistic Missile Division, this innovation proved its efficacy by guiding a Thor-Able nose cone to a precise target five thousand miles away, allowing for a successful aerial and maritime recovery. The system utilized a missile-borne transmitter to feed continuous data to ground-based radar and a Remington Rand Univac computer, which calculated real-time steering corrections. By keeping the primary command equipment on the ground...

Mac's Radio Service Shop: Something Borrowed

Mac's Radio Service Shop: Something Borrowed, January 1952 Radio & Television News - RF CafeIt's Friday afternoon as I post this installment of Mac's Radio Service Shop from a 1952 edition of Radio & Television News magazine - the perfect way to burn off the last few minutes of your work week while waiting for the shift-ending whistle to blow. John T. Frye authored many of these stories that used main characters Mac McGregor, proprietor of Mac's Radio Service Shop and sidekick technician Barney to set up a situation and dialog whereby the highly experienced Mac imparts sage advice to Barney regarding things electronics in nature. Topics range from safely troubleshooting a high voltage power supply to tracking down noisy capacitors and how to treat customers equitably. Today's lesson is on the employment of "repurposed" (a term not yet invented in 1952...

1st Mention of Electric Light The New York Times

Thomas Edison Electric Light Bulb Patent 223898 - RF CafeThomas Edison applied on November 4, 1879 to the U.S. Patent and Trademark Office for a patent on his "Electric-Lamp." Patent number 223898 A was awarded on January 27, 1880. Remember those years. While searching for technical headlines today, I ran across an article in the New York Times where they point out the first-ever mention of electric lights in their newspaper. Per the article "The Arrival of Electric Light," The New York Times first wrote of the technology on April 15, 1858. On that day, "Our Own Correspondent" in Havana described celebrations of Holy Week that included "an electric light" cast across the harbor...

Crystal Diodes in Modern Electronics

Crystal Diodes in Modern Electronics, February 1952 Radio & Television News - RF CafeThis is part 5 in a series that began in the October 1951 issue of Radio & Television News magazine. Previous articles dealt with crystal diodes in AM and FM radios, and this article shift gears by moving into television applications. Crystal diodes were and are still used in frequency generation, envelope detection, frequency mixing, and AC signal rectification. Vacuum tubes could be used for the latter three applications but many physical issues such as size, weight, power consumption, and heat dissipation proved to be major drawbacks as designers strived to reduce the size of electronics assemblies, make them more energy efficient, lower the cost of manufacturing, increase reliability, and decrease weight...

Unidirectional Dipole Loop Antenna

The Unidirectional Dipole Loop Antenna, September 1959 Radio-Electronics - RF CafeThis article from a 1959 issue of Radio-Electronics magazine details a simple, effective method to convert a standard dipole antenna into a unidirectional, broadband performer by bending it into a circular loop and terminating the ends with a non-inductive resistor. By utilizing a cross-shaped support frame with TV standoff insulators, a builder can easily construct this antenna for the 6-meter band or higher. The design is noted for its impressive front-to-back ratio and surprising operational versatility across a wide frequency range, even maintaining performance when improperly sized. Offering increased gain at harmonic...

Sylvania Electric Advertisement

Sylvania Electric Advertisement, January 1950 Radio & Television News - RF CafeAs evidenced in these mid-last-century magazine advertisements, Sylvania Electric marketing moguls learned early what sells products by exploiting the nature of their audience. The cartoon-style ads shown here appeared in social publications like Look, Life, and Collier's, where both men and women - many of them numbnuts - are the expected audience. Compare these with the type of ad run by Sylvania in a "serious" magazine like Radio-Craft...

Bell System Opens Transcontinental Radio-Relay

AI-enhanced and colorized version of radio-relay station at Creston, Wyoming - RF CafeBilled at the time as the longest microwave relay system in the world, this report on Bell Telephone Systems' transcontinental installation came just a month after being put into commercial service. At a cost of $40 million ($512 million in 2026 dollars per BLS Inflation Calculator), the system relays telephone calls and radio and video program material along a chain of 107 microwave towers, spaced approximately 30 miles apart. It was a big deal to be able to watch a TV show from New York City in Los Angeles, and vice versa; we take worldwide broadcasts for granted nowadays...

Anatech Intros 3 New Filter Models for April

Anatech Electronics Intros 3 New Filter Models for April 2026 - 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 models have been added to the product line in April, including a 4.9 to 24 GHz MHz suspended stripline highpass filter, a 9200 MHz cavity bandpass filter with 250 MHz bandwidth, and a 1 MHz LC bandpass filter with 350 kHz bandwidth. Custom RF power filter and directional couplers designs...

Now - Metal Tubes

Now - Metal Tubes, June 1935 Radio-Craft - RF CafeToday as I write this it is New Year's Eve. The year 1935 could be considered "metal tube's eve" as a new paradigm was about to hit the world of high frequency circuit design. Thentofore[sic], vacuum tubes were almost exclusively encased in a glass envelope. Metal-encased tubes provided, among others, benefits like better heat dissipation, smaller physical size, ruggedness, inherent RF shielding, and lower parasitic values of capacitance and inductance due to smaller plate areas and shorter lead lengths, respectively. The highest barrier to widespread adoption, history would show, was the higher cost of production that made consumer products more expensive at a time when not every household saw the need for...

Oscillator Squegging

Oscillator Squegging, September 1959 Radio-Electronics - RF Cafe"Squegging," a phenomenon likened to the rhythmic spurts of a manual water pump, occurs when an oscillator undergoes periodic cycles of oscillation followed by a dead period. This happens when an excessive time constant in the grid circuit, often caused by a faulty resistor or capacitor, drives the tube to cutoff, only for it to restart once the bias bleeds off. In radio and television, this manifests as audible buzzing, intermittent sound, or dark holes in the picture. Historically, the term "squeg" emerged in the specialized fields of radio engineering and electronics during the early 20th century, likely originating as a form of "self-quenching," descriptive of the erratic...

RCA Advertisement

Radio Corporation of America (RCA) Advertisement (AI enhancement), January 1952 Radio & Television News - RF CafeIf Radio Corporation of America (RCA) was still in existence today, undoubtedly it would be running an advertisement mentioning not just radio and television in their list of wireless communications accomplishments, but also cellphones, satellite navigation (GPS), cable television, and Wi-Fi. Founded in 1919, RCA was bought by General Electric in 1986 and then subsequently broken into components and sold off to other companies like Sony, NBC (National Broadcasting Company), and Comcast. This RCA advertisement heralding Marconi's Morse code message "first forged in 1901 from the mere sound of three dots" appeared in a 1952 issue of Radio & Television News magazine...

Technical Headlines - RF Cafe

• UK's Fractile Chip Facility Gets £100m Expansion

• Choosing an Antenna for Compliance Testing

• Huawei Wins 8 GLOMO Awards at MWC Barcelona

• Smartphone Shipments to Fall 7% in 2026

• February Chip Sales up 61.8% YoY

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.

Loral Distributor Products

Loral Distributor Products, November 1968 Radio-Electronics - RF CafeHere is another one of those ads you would not likely see in a present day engineering magazine. Today, you'll routinely find racier images in JC Penny and Target advertisements (although in the latter example the girl might not be a real girl). Loral Electronics is a well-known defense systems contractor founded in the late 1940s by William Lorenz and Leon Alpert. Loral specialized in aerospace and avionics (airborne) systems like radar, radios, satellite navigation and communications. They also had a component distribution division which sold, among other items, the Arcolytic capacitors represented in this 1968 Radio-Electronics magazine promotion. Lockheed Martin bought Loral in 1996, the same year Loral was accused of transferring missile stabilization technology to China, which was useful in their Long March intercontinental ballistic missile (ICBM) program.

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...

The Whole Ohm Family - R, X, and Z

The Whole Ohm Family - R, X and Z, June 1931 Radio-Craft - RF CafeHere is yet another treatise on the subject of reactance and resistance. Considering that the date on this Radio-Craft magazine is 1931, it was probably amongst the first to publically discuss such newfangled topics outside of a formal university setting. The layman just was not accustomed to being bothered with such esoteric concepts. After all, not many decades previous a person might be burned at the stake for exercising such witchcraft as speaking of "imaginary" numbers as is required for a complete analysis of alternating circuits. This article, however, does not actually get into complex numbers, but future ones did...

United Electronics Company Advertisement

United Electronics Company Advertisement, April 1945 Radio News - RF Cafe"QRT" is the Q-code used in amateur radio to tell someone to stop transmitting. Hams very much anticipated the day when Germany and Japan would be defeated, the war would end, and they could go home to resume their beloved radio hobby. You might know - or not - that during World War II ham radio transmissions were prohibited in the U.S. for a mix of reasons. Foremost was to inhibit the broadcasting of information, intentionally or unintentionally, that might give away strategic military strategy. Innocent chatter about whose son left for boot camp, where he was going afterwards, what his ambitions and fortes were, which factory Mom and Aunt Rosie worked for and what they did (Auntie was riveter, maybe), who died in service to his country, blackout hours, scrap material recycling collections, all was potential fodder for enemy tacticians. Another reason for the prohibition was to free up production materials and labor for the making of military equipment. The fate of the free world depended on it - literally...

Gray Market Electronics - Reaping What We've Sown

Gray Market Electronics - Reaping What We've Sown - RF Cafe SmorgasbordGray market electronics components have been a problem for a long time. An extensive article appeared recently in EE Times reporting on a case based on a small operation in south Florida that was importing and re-selling counterfeit parts to military, aerospace, medical, and other product manufacturers. The Feds charged them "with conspiracy, trafficking in counterfeit goods and mail fraud for knowingly importing more than 3,200 shipments of suspected or confirmed counterfeit semiconductors into the United States, marketing some of the products as "military grade" and selling them to customers that included the U.S. Navy and defense contractors." The good news might be that this particular scam operation was caught and stopped, but the bad news is, according to the story, that many more are never prosecuted...

Radio Physics Course - Inductors

Radio Physics Course - Inductors, May 1934 Radio News and the Short-Wave - RF CafeFinding the equation for the inductance of a standard tightly-wound, single-layer inductor is very easy. What, though, if you needed to determine how to build an iron-core inductor or to build a choke coil with a silicon steel laminated transformer-iron core where the windings have an air gap between them? Who ya gonna call? Alfred Ghirardi, of course, or at least his ghost through this article from a 1934 edition of Radio News and the Short-Wave magazine. If you also need advice - complete with drawings - on how to wind a coil that will not induce a killer counter-EMF when a switch is opened (as with a solenoid), then here, too, is your source...

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...

R-E Puzzler

R-E Puzzler, August 1967 Radio-Electronics - RF CafePuzzlemeister Edmund Braun refers to his challenge as an "only-across-word puzzle." It is similar to others he has created for Radio-Electronics magazine - this one appearing in the August 1967 issue. Not having "cross-words" running vertically can make things a bit more difficult, but he does provide at least one letter for each word. In spite of its era, you shouldn't have too much problems with most of it. There are a couple component types that are no longer part of the electronics experience. Others, like number 5, now usually go by a different name (I mistaken thought it was a variation of gutta-percha, based on the "tt" near the end). The symbols shown have no bearing on the puzzle, BTW. Of the two longest words, number 1 is easy, but number 15 will be known only by those familiar with older analog calculator methods. I'll admit to knowing the root part of the word, but not the prefix (hint: it begins with "a")...

Engineering & Science Crossword Puzzle for March 31

RF Cafe Engineering & Science Crossword Puzzle March 31, 2019Since 2000, I have been creating custom technology-themed crossword puzzles 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...

Mac's Radio Service Shop: Intermittents Still Pursue

Mac's Radio Service Shop: Intermittents Still Pursue, February 1949 Radio & Television News - RF CafeMac McGregor, owner of Mac's Radio Service Shop, can always be counted on to provide his apprentice technician, Barney, with a lesson from his own life-long attendance at the School of Hard Knocks. Barney is your stereotypical young buck whose level of seriousness needs occasional alignment, just as do the radio and television sets he services. In this episode, I can't find where Mac actually solved the intermittent electrical condition believed to be causing the problem - weird. The "Mac's Radio Service Shop" series ran in Radio & Television News magazine for many years prior to a similar electronics story series called "Carl & Jerry" that appeared in Popular Electronics. Both were created by consummate storyteller John T. Frye...

U.S.A. Calling

U.S.A. Calling, December 1942 QST - RF CafeAlthough the Japanese attack on Pearl Harbor on December 7, 1941, was a complete surprise and shock to the nation, that fact that the United States would eventually be drawn officially into World War II was well known. The amateur radio community had begun talking about the potential impact on radio communications hobbyists earlier in the year, as evidenced by articles printed in QST and other magazines. Within a couple weeks of Congress declaring war, all unauthorized transmissions from Ham stations were terminated in order to prevent both intentionally and unintentionally conveyance of information that could proves useful by the enemy. Along with being a patriotic bunch that were eager to help defeat Axis powers, they also loved their hobby and willingly (in most instances) made critical components of their equipment available for battlefield use. Items such as meter movements, tuning capacitors, and even energy storage cells (lead-acid batteries) were needed for troops on the ground, at sea, and in the air. The American Radio Relay League (ARRL) devoted a lot of print space to promoting an attitude of service and sacrifice, as with this article...

Bell Telephone Laboratories

Bell Telephone Laboratories, July 1959 Electronics World - RF CafeBell Telephone Laboratories was largely responsible for designing and building a communications system that was the envy of the world. Innovation on the part of Bell engineers, manufacturing staff that produced the equipment, and technicians who serviced the systems deserve the credit as do management types who made funds and opportunity available to the aforementioned. As the number of telephone service subscribers grew and reliability became even more vital to business, law enforcement, and national defense, new methods had to be devised. In the late 1950s, Bell introduced the concept of wireless microwave links at 11 GHz (X band), which at the time X band was primarily used (at 10 GHz) by precision approach aircraft radar. This advertisement in a 1959 issue of Electronics World magazine promoted Bell's achievement...

Trio Manufacturing Company Zig-Zag Antenna

Trio Manufacturing Company Zig-Zag Antenna, October 1952 Radio-Electronics - RF CafeThis advertisement for a Zig-Zag Antenna, offered by Trio Manufacturing, appeared in a 1952 issue of Radio-Electronics magazine, states "patent pending." When I looked up "zig-zag antenna" at the U.S. Patent and Trademark Office (USPTO), the earliest assignment I could find for that configuration was US3213457A, "Zig-zag antenna," designed by John W. Carr and assigned to Lockheed Corporation, in 1961. Maybe Trio never received a patent, or my search wasn't thorough enough. The claim to fame from Trio's design is that the zig-zag pattern consisted of various element lengths that resonated on specific channels while all others acted as parasitic elements. I don't know if it is coincidence or intention (probably the latter), but there are twelve sections that might correspond to channels 2 through 13. There are not many (if any) zig-zag antennas being sold by companies today for amateur or other uses. It evidently was just another fad to have something different from all the rest - and there were lots of unique TV antenna configurations back in the day which promised to pull in far-away stations, reduce ghosts, noise, etc...

Electronics-Themed Comics

Electronics-Themed Comics, April 1948 Radio News - RF CafeIt's been a little while since I posted any of the great electronics-themed comics from my vintage magazines, so here are half a dozen from the April 1948 issue of Radio News. My favorite is the one from page 102 where the farmer mistook his wife's waffle iron for a heating pad (stereotyping rural dwellers as ignoramuses was fair game in humor back then). To fully appreciate the page 130 comic requires you noting that World War II had just ended a couple years earlier and there were a lot of electronics and communications technicians (former soldiers) who were by then working in the private realm. Just as nowadays the publically spoken words of politicians are available online, in the record and magnetic tape era many speeches were made available to the public. I have an LP record of speeches delivered by Winston Churchill, General Patton, Franklin Roosevelt, and other notables of the 1940s. In the page 192 comic, during an argument with a friend over some point, he is armed with recordings of President Harry S. Truman to support his case...

1 to the 4th Power Amplification in Star Trek Redux

1 to the 4th Power Amplification in Star Trek Episode - RF CafeA few years ago I posted a note about a technical faux pas on an episode of Star Trek titled "Court Martial," where Captain Kirk makes a comment ordering the ship's auditory sensors to be boosted "on the order of 1 to the 4th power," (14) in order to pick up heart beats. RF Cafe visitor Sam M. just sent me a note offering a possible - and plausible - explanation for the gaff. If you are a devoted Trekkie looking for a response to your apostate friends when confronted over the scene, read on...

Don't Underrate Transistors

Don't Underrate Transistors, September 1960 Electronics World - RF CafeTransistors always have been and always will be prone to damage or destruction if operated at temperatures higher than their designed ranges. Modern foundry processes have made it possible for greater heat tolerances for a given transistor size, but care must be taken during circuit design to assure that the devices will under normal ambient conditions not exceed their intended temperature range. Often a heatsink is required in order to use a transistor at its full rated temperature, and sometimes extensive measures are needed to keep the heatsink within an acceptable maximum temperature. Take a look inside your computer for an example of how far heatsink technology has come. The liquid-cooled (desktop) and heat pipe-cooled (laptop) schemes are amazingly efficient and capable of dissipating heat from the CPU package, which would otherwise fry in milliseconds without it...

GATT, Bell Labs, Space Needles, & In-Car Entertainment Systems

GATT, Bell Labs, Space Needles, & In−Car Entertainment Systems - RF CafeThe General Agreement on Tariffs and Trades (GATT) has been around for a really long time - since 1947, shortly after the end of World War II. It changed its name to the World Trade Organization (WTO) in 1995. Japan was admitted as a GATT signatory in 1964 according to this Electronics magazine newsletter. One of the conditions for membership was allowing foreign ownership of businesses on Japanese soil - previously prohibited. Texas Instruments was the first American company to establish a presence there. Japanese industry was just getting a foothold on manufacturing and selling into foreign markets in the mid 1960s, and was still working to shed its reputation - deserved or not - of producing inferior quality goods. Increasing foreign presence and dependence on the country's economic well-being was a good thing for them. In fact, many pundits believe that the globalization of production is key to preserving peace (or at least not war) between certain countries...

The Renode - A New Gridless Tube

The Renode - A New Gridless Tube, February 1936 Radio-Craft - RF CafeCompetition amongst countries and businesses existed long before the advent of radio receivers. Here is an interesting story which demonstrates how international politics and corporate policies has been part of the electronics industry since its inception. In order to circumvent what were considered to be outlandish patent licensing fees, Danish engineer Carl Arne Scheimann Jensen developed a new "gridless" type of vacuum tube (aka valve) which was called the "Renode." Rather than using a screen grid in the path between the cathode and plate, the Renode employed two sets of beam concentrator and deflector plates on either side of the electron beam's path to modulate the conduction. According to measurements it provided a slight improvement in both linearity and selectivity. The article's author hints at the possibility that further manipulations and back-room deals might eventually scuttle the effort to bring Renodes to the mass market...

Amplifier Solutions Corporation (ASC) - RF Cafe