Hugo Gernsback - A Concise Biography  Being a big fan of Hugo Gernsback's technical work through his many electronics-related publications (The Electrical Experimenter, Radio Amateur News, Radio News, Radio-Craft, Short-Wave Craft, Radio-Electronics, etc.), I decided to task a couple of different AI models with conducting a deep-dive research project on all aspects of his background - family, schooling, business, finances, politics, etc. Then, I had the AI combine all results, while avoiding duplication, and filtering out "facts" that cannot be validated. A lot of websites contain Hugo Gernsback bios of varying lengths, but this, I believe, is the most comprehensive and concise. Photos were collected across the WWW...
Amateur Radio Crossword Puzzle  This custom Amateur Radio crossword puzzle contains many words particular to Amateur Radio (labeled with an asterisk *). 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...
How Audions Were Built  If 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...
Student's Radio Physics Course - Series & Parallel Circuits  Not everyone who visits websites like RF Cafe is a seasoned electronics veteran. While I and most likely you, too, can do series and parallel circuit analysis (and series/parallel for that matter, possibly using Fourier or La Place transforms for reactive AC circuits) in our sleep, many are recently getting into the wonderful world of electronics who are just coming of age or have suddenly at a later point in life developed a passion for the craft. Accordingly, this article from Radio News magazine provides yet another tutorial on the fundamentals of series and parallel circuit analysis. Only resistors and basic Ohms law are covered...
Exodus AMP20005 18-40 GHz, 20 W SSPA  Exodus Advanced Communications presents the AMP20005 is a solid-state RF power amplifier operating from 18.0 to 40.0 GHz with 20 W minimum power. Designed for EMI/RFI, laboratory, CW/pulse, and communication applications, the amplifier features instantaneous wide bandwidth, Class A/AB linear design, built-in protection circuits, and remote-control capabilities. Features Include * Designed for EMI/RFI, lab, CW/Pulse and all communications applications * Small form factor, rack-mounted system * Class A/AB linear design * High power advanced technology devices * Instantaneous ultra-wide bandwidth * Built-in protection circuitry...
Thévenin's Theorem Quiz  stands as one of the most powerful circuit simplification tools in electrical engineering. It states that any linear, two-terminal network - no matter how complex - can be reduced to an equivalent circuit comprising a single voltage source (VTH) in series with a single resistance (RTH). To determine these parameters, engineers short all independent voltage sources, open all independent current sources, and calculate the equivalent resistance seen from the terminals. VTH is simply the open-circuit voltage across the terminals. This theorem proves invaluable when analyzing how different loads affect circuit performance, as the equivalent circuit remains unchanged...
Comics with an Electronics Theme  Here are a couple more tech-themed comics from a vintage electronics magazine (Popular Electronics). The one from page 101 reminds me again about how different the world of retail sales is today compared to just two short decades ago. Prior to the advent of online marketing and sales, you either walked into a brick and mortar (a term rarely heard before the Internet era) type store and walked out with your purchased product, or you thumbed through a catalog and placed an order either by mail or telephone. Most people opted to pay for a postage stamp rather than pay the long distance phone charge (a term rarely heard today). Free overnight or 2-day shipping from many e-stores makes...
Ward Para-Con Antenna  The word prefix "para" can mean "above and beyond" or "resembling" or "abnormal or incorrect." Ward Products probably preferred first two be inferred by potential customers when naming their PARA-CON television antenna, although it actually is a shortening of "parabolic." The "con" part is a shortening of "conical." After reading the text of this full-page advertisement from a 1951 issue of Radio & Television News magazine, I'm inclined to assign the third prefix meaning of "para" to it. Then, add in the "con" part where "con" can take on either the noun form meaning of "disadvantage" or the verb form definition of "to trick or defraud," and you get what this antenna truly represented in terms...
Transmission-Line Feed for Short-Wave Antennas  When someone with the first name of "True" writes an article about transmission line feeds for short-wave antennas, you should probably take note. This very topic has been covered in detail many times since the use of impedance-matched transmission lines have been in use (more than a century), but since there are always people new to the concept, it is good to keep introducing the topic on a regular basis."Transmission-Line Feed for Short-Wave Antennas" appeared in a 1932 issue of QST magazine. Even in this era of prefabricated everything, it still often comes down to winding coils and adjusting cable lengths to get optimal impedance matches between transceivers and antennas...
Electrodrome: Fog and Poison Gas Dissipator  The 1934 Flying Aces magazine's "Electrodrome: Fog and Poison Gas" article described a device invented by William Haight that allegedly used high-voltage electrostatic fields to "precipitate" fog over a radius of about 1.5 miles and, by extension, might neutralize poison gas. The concept was based on a real physical phenomenon - charged droplets and aerosols can be moved, collected, or coalesced by electric fields - but the article's large-scale claims and Haight's atmospheric theory do not align with modern atmospheric physics. The likely outcome was failure as a practical outdoor fog-dispersal or poison-gas-defense system. I found no credible evidence that Haight's electrodrome was adopted by airports, the U.S. government, military...
Electronic Crossword Puzzle  This "Electronic Crossword" appeared in the September 1958 issue of Radio & TV News magazine. Its creator, John Gill, designed specialty theme crossword puzzles for many other editions of Radio & TV News and Electronics World (see the big list at the bottom of the page). He considered this crossword to be a "fooler" because he claims to include many "unusual definitions and a number of obscure words which you will have to work around if your vocabulary of 'exotic words' is rusty." It really doesn't seem so difficult to me, and anyone used to working my custom RF Cafe Crosswords will have no problem with it...
Building Your Own Audio Frequency Choke Coils  One very satisfying aspect of 'rolling your own' audio frequency coils (aka chokes, aka inductors), is how well the simple inductance equations match measured end results. Unless you really manage to mangle the job, if you use the right equation and are reasonably careful to observe wire size, spacing (including insulation), and core diameter, you will be amazed at how close practice matches theory. Although strictly speaking audio frequencies run from a few Hertz up to maybe 15 kHz for people with really good hearing. My experience is that similar success can be had even into the low MHz realm with just a little tuning required. It's not until you get into the realm of self-resonance...
Heath Company: Heathkit Advertisement  claim to fame was that it was able to offer user-assembled kits of high quality electronic products at a price lower than what equivalent factory assembled equivalents would cost. While that is probably generally the case, it is difficult to gauge what the relative quality really is. Some of the kits were easy to assemble for even people with little experience, but a good portion of them required familiarity with soldering and how electronics were put together. The instructions provided were very thorough, complete with photos and drawings of how each step should look. In fact, according to a 1972 installment of Mac's Service Shop entitled "Philosophy of a Kit Manufacturer," every Heathkit kit...
RF Cafe Quiz #92: Electric Fields  An electric field is a vector field that surrounds electrically charged particles and exerts a force on all other charged particles in the field, either attracting or repelling them. It is the fundamental manifestation of the electric force, acting as the intermediary through which charges communicate. From the static potential of a charged capacitor plate to the dynamic, wave-propagating fields of an antenna, electric fields are central to electronics, semiconductor physics, and electromagnetics. This Electric Fields Quiz explores the principles that govern these invisible forces, including the inverse-square relationship defined by Coulomb's Law, the concept of electric potential (voltage)...
The Tecnetron: Competitor to the Transistor?  Breaking news from May 1958: "Hardly a month passes nowadays without the announcement of some 'sensational' new amplifying device. The great majority of these startling inventions, after their brief flurry in the popular and technical press, disappear into oblivion. But we believe that the Tecnetron, just announced in France, has a brilliant and enduring future." Have you ever heard of a Tecnetron? I didn't think so; neither had I before reading this article in Radio-Electronics. I guess that pretty much negates the preceding prediction. The holy grail of the Tecnetron, whose etymology in and of itself is worth reading about (it's not what you would guess), is that its transconductance...
Simpson Electric Company Advertisement  Before the days of cheap stuff from China, the supply of most common items- particularly high technology - were the domain of relatively few companies. In some ways it was not entirely a bad thing because, at least theoretically, the economy of scale enabled larger producers to leverage bulk buying, well-equipped development labs and manufacturing equipment, and pooling of talent resources to sell quality products at a lower price. Of course it required that the company had serious competitors or monopolistic tendencies resulted in gouging - it's human nature, unfortunately. Hewlett Packed, as much as I appreciate what the company did for electronics test equipment, had gotten...
Varian Associates Radar Illustrations by C.E.B. Bernard  Frequent RF Cafe visitor who goes by the moniker "Unknown Engineer" sent me a hyperlink to a PDF file on Amazon's CloudFront* content delivery network (CDN - basically a file server) that contains no fewer than 17 amazing radar and vacuum tube related line drawings published by Varian Associates' TWT Division, Palo Alto Tube Division, Solid State Division, Eastern Tube Division, Western Tube Division, Solid State West Division. These highly detailed and busy drawings were done around 1975 by British illustrator/artist C.E.B. Bernard; a search for his works did not reveal much. The events shown are fictitious, as are the accompanying hand-printed stories. Some of the puns...
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 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.  Who cares about television antennas these days, you're probably asking? Many people might care soon. The December 2012 edition of the IEEE's Spectrum magazine had an article titled, "TV's Future: The Broadcast Empire Strikes Back." According to author Lynn Claudy, the Advanced Television Systems Committee (ATSC) is working on a standard called Mobile DTV (MDTV) in the United States. MDVT enables broadcast stations to deliver programming to some cellphones, laptops, tablets and to moving television screens in cars, trains, and buses. Furthermore, a scheme to enable on-demand programming, user feedback (voting, polls, quizzes, games), and other advanced features is under investigation...
 Prior to the invention of gas (CO2, HeNe) and chemical (iodine, hydrogen fluoride) lasers in the early to middle 1960s, lasers (light amplification by stimulate emission of radiation) were made using rare earth gems (ruby). Evolution occurred rapidly in power output, wavelength (color), stability, purity, and lasing source type.The concept of lasers were introduced in science fiction, but believe it or not the first recorded instance of the term "LASER" was in a paper written in 1959 by Gordon Gould. Development flowed from the preexisting maser (microwave amplification by stimulate emission of radiation) knowledge. This 1960 news item in Electronics World magazine reported on Dr. Theodore H. Maiman's work...
 NASA (and its predecessor NACA), and private and public operators have been monitoring solar events in the optical realm for many decades while attempting to correlate terrestrial phenomena with it. Auroral light displays in the extreme polar regions have long been known to be caused by solar flare and coronal mass ejections (CME). With the advent of radio, the electrical nature of the upper atmosphere became evident when static (AM) and long range propagation affected long range communications. Extreme CME activity eventually was associated with behavior of the electrical power grid; indeed, massive blackouts and brownouts are to blame for many. Last but not least...
 No matter how proud I was of my family name, I do believe I would refrain from using "Kluge" as a company moniker. Maybe the word did no connate the same meaning in 1946 when this advertisement for the Kluge Electronics "California Kilowatt" Amateur Radio Station appeared in Radio-Craft magazine. An extensive WWW search turned up no examples of any surviving Kluge "California Kilowatt" Amateur Radio Stations. One QRZ website discussion supposed that none were ever manufactured. Per Wikipedia: "A kludge or kluge (klooj) is a workaround or quick-and-dirty solution that is clumsy, inelegant, inefficient, difficult to extend and hard to maintain." It has an interesting etymology...
 There is little incentive to build your own field strength meter these days when commercial instruments are readily available and relatively inexpensive. For instance, you can buy an MJF-801 FSM with a 100 kHz to 500 MHz spectrum coverage for just $45, brand new. More sophisticated, calibrated instruments are available for a lot more, but this basic unit is dirt cheap. However, if you want to read a little about the theory behind a field strength meter and see how one goes together, this article from a 1960 issue of Popular Electronics magazine provides that opportunity...
 Here is a snapshot of how a career in electronics looked in the year 1960, per an article in Electronics World magazine. The field of electronics was in transition from vacuum tube technology to semiconductors, from point-to-point wiring in chassis to printed circuit boards, and from analog to digital. Opportunities abounded from all angles - legacy, contemporary, and futuristic. Jobs in electronics were readily available for people of education levels ranging from high school to post-graduate. Annual pay began at around $2,600 for assembly line workers to over $5,000 for experienced technicians. Assistant engineers and communications specialists with some college began at around $3,000...
 One sure giveaway to the age of a picture is the presence of a wheat penny, a buffalo nickel, or a Mercury dime. This 1957 advertisement in Radio & Television News magazine for Channel Master antennas has all three. It shows a walking Liberty half dollar as well. Quarters haven't changed much over the years, with George Washington's head on the obverse side since 1932. The wheat penny design ended in 1959 when the Lincoln Memorial was put on the reverse side in its place. Thomas Jefferson's head has been on the nickel since 1938. Theodore Roosevelt's head was ensconced on the obverse of the dime in 1946. John F. Kennedy was placed on the half dollar obverse in 1964. This ad is about...
 This Radio Theme crossword puzzle for August 15th, 2021, contains only words and clues related to engineering, mathematics, chemistry, physics, and other technical words. 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., Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!
 It has been a while since posting on of these Radio Data Sheet 333 that often appeared in vintage electronics magazines like Radio-Craft. This one is for General Electric Radio Models 100, 101, 103 and 105. The RadioMuseum.org website has a very nicely restored General Electric Model 103 radio. Per their description: "The General Electric 103 is an AC/DC operated 5 tube BC band receiver. The BC band frequency tuning range is 540-1600 kHz. Has built-in loop antenna with provisions for connecting an external antenna. The following models use the same schematic and chassis but have different cabinets..." A few Model 100 versions show up on eBay in case you might...
 If you have seen many of the articles I post from vintage electronics magazines, you know I often compare prices from the magazine's era to today's prices. The online Inflation Calculator from the Bureau of Labor Statistics (BLS) is as good as any, so it is used. This RCA advertisement in a 1946 issue of Radio-Craft magazine boasts of how drastically the cost of vacuum tubes has come down since 1923. It claims a $9 tube in 1923 costs a mere 80¢ in 1946; that is about 1/11th of the original price. Prior to around 1965, inflation was very low, so the inflation-adjusted price for the $9.00 tube would be $9.80 in 1946 - a full 23 years later (a 9% increase, per the BLS). Therefore, the 80¢ price...
 With more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks, and more. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...
 Radio-Craft magazine's "Radio Term Illustrated" feature of electronics-themed comics was very popular. Famous artist Frank Beaven, who created illustrations for numerous publications at the time, took ideas submitted by readers and turned them into clever word (or phrase) pictures. You will need to consider some of them from the viewpoint of someone in the 1945 era in which they were made. I don't know if women Navy personnel are referred to as WAVES (Women Accepted for Volunteer Emergency Service ) anymore - probably not. Arcing from motor armature brushes was a common cause of radio interference in the days of AM broadcasting, hence "brush discharge." Enjoy!
 While a bit far-fetched, this Carl & Jerry saga from the June 1963 issue of Popular Electronics magazine has the two amateur radio hobbyists cum detectives applying their knowledge of standing waves and an invention called SNARE, "Signal Net for Actuating Radio-sensitive Explosives," by Irwin Ehlmann, to thwart an assassination attempt on a visiting foreign dignitary. The name of the patent is actually "Method and apparatus for detonating radio frequency sensitive blasting caps," but the principal is the same. The choice by author John T. Frye of a halo antenna on their mobile shortwave rig was probably no coincidence given the guardian angel role it played in the adventure...
 On 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...
 This Engineering Theme crossword puzzle for August 8th, 2021, contains only words and clues related to engineering, mathematics, chemistry, physics, and other technical words. 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., Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!
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Who cares about television antennas these days, you're probably asking? Many people might care soon. The December 2012 edition of the IEEE's Spectrum magazine had an article titled, "TV's Future: The Broadcast Empire Strikes Back." According to author Lynn Claudy, the Advanced Television Systems Committee (ATSC) is working on a standard called Mobile DTV (MDTV) in the United States. MDVT enables broadcast stations to deliver programming to some cellphones, laptops, tablets and to moving television screens in cars, trains, and buses. Furthermore, a scheme to enable on-demand programming, user feedback (voting, polls, quizzes, games), and other advanced features is under investigation...
Prior to the invention of gas (CO2, HeNe) and chemical (iodine, hydrogen fluoride) lasers in the early to middle 1960s, lasers (light amplification by stimulate emission of radiation) were made using rare earth gems (ruby). Evolution occurred rapidly in power output, wavelength (color), stability, purity, and lasing source type.The concept of lasers were introduced in science fiction, but believe it or not the first recorded instance of the term "LASER" was in a paper written in 1959 by Gordon Gould. Development flowed from the preexisting maser (microwave amplification by stimulate emission of radiation) knowledge. This 1960 news item in Electronics World magazine reported on Dr. Theodore H. Maiman's work...
NASA (and its predecessor NACA), and private and public operators have been monitoring solar events in the optical realm for many decades while attempting to correlate terrestrial phenomena with it. Auroral light displays in the extreme polar regions have long been known to be caused by solar flare and coronal mass ejections (CME). With the advent of radio, the electrical nature of the upper atmosphere became evident when static (AM) and long range propagation affected long range communications. Extreme CME activity eventually was associated with behavior of the electrical power grid; indeed, massive blackouts and brownouts are to blame for many. Last but not least...
No matter how proud I was of my family name, I do believe I would refrain from using "Kluge" as a company moniker. Maybe the word did no connate the same meaning in 1946 when this advertisement for the Kluge Electronics "California Kilowatt" Amateur Radio Station appeared in Radio-Craft magazine. An extensive WWW search turned up no examples of any surviving Kluge "California Kilowatt" Amateur Radio Stations. One QRZ website discussion supposed that none were ever manufactured. Per Wikipedia: "A kludge or kluge (klooj) is a workaround or quick-and-dirty solution that is clumsy, inelegant, inefficient, difficult to extend and hard to maintain." It has an interesting etymology...
There is little incentive to build your own field strength meter these days when commercial instruments are readily available and relatively inexpensive. For instance, you can buy an MJF-801 FSM with a 100 kHz to 500 MHz spectrum coverage for just $45, brand new. More sophisticated, calibrated instruments are available for a lot more, but this basic unit is dirt cheap. However, if you want to read a little about the theory behind a field strength meter and see how one goes together, this article from a 1960 issue of Popular Electronics magazine provides that opportunity...
Here is a snapshot of how a career in electronics looked in the year 1960, per an article in Electronics World magazine. The field of electronics was in transition from vacuum tube technology to semiconductors, from point-to-point wiring in chassis to printed circuit boards, and from analog to digital. Opportunities abounded from all angles - legacy, contemporary, and futuristic. Jobs in electronics were readily available for people of education levels ranging from high school to post-graduate. Annual pay began at around $2,600 for assembly line workers to over $5,000 for experienced technicians. Assistant engineers and communications specialists with some college began at around $3,000...
One sure giveaway to the age of a picture is the presence of a wheat penny, a buffalo nickel, or a Mercury dime. This 1957 advertisement in Radio & Television News magazine for Channel Master antennas has all three. It shows a walking Liberty half dollar as well. Quarters haven't changed much over the years, with George Washington's head on the obverse side since 1932. The wheat penny design ended in 1959 when the Lincoln Memorial was put on the reverse side in its place. Thomas Jefferson's head has been on the nickel since 1938. Theodore Roosevelt's head was ensconced on the obverse of the dime in 1946. John F. Kennedy was placed on the half dollar obverse in 1964. This ad is about...
This Radio Theme crossword puzzle for August 15th, 2021, contains only words and clues related to engineering, mathematics, chemistry, physics, and other technical words. 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., Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!
It has been a while since posting on of these Radio Data Sheet 333 that often appeared in vintage electronics magazines like Radio-Craft. This one is for General Electric Radio Models 100, 101, 103 and 105. The RadioMuseum.org website has a very nicely restored General Electric Model 103 radio. Per their description: "The General Electric 103 is an AC/DC operated 5 tube BC band receiver. The BC band frequency tuning range is 540-1600 kHz. Has built-in loop antenna with provisions for connecting an external antenna. The following models use the same schematic and chassis but have different cabinets..." A few Model 100 versions show up on eBay in case you might...
If you have seen many of the articles I post from vintage electronics magazines, you know I often compare prices from the magazine's era to today's prices. The online Inflation Calculator from the Bureau of Labor Statistics (BLS) is as good as any, so it is used. This RCA advertisement in a 1946 issue of Radio-Craft magazine boasts of how drastically the cost of vacuum tubes has come down since 1923. It claims a $9 tube in 1923 costs a mere 80¢ in 1946; that is about 1/11th of the original price. Prior to around 1965, inflation was very low, so the inflation-adjusted price for the $9.00 tube would be $9.80 in 1946 - a full 23 years later (a 9% increase, per the BLS). Therefore, the 80¢ price...
With more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks, and more. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...
Radio-Craft magazine's "Radio Term Illustrated" feature of electronics-themed comics was very popular. Famous artist Frank Beaven, who created illustrations for numerous publications at the time, took ideas submitted by readers and turned them into clever word (or phrase) pictures. You will need to consider some of them from the viewpoint of someone in the 1945 era in which they were made. I don't know if women Navy personnel are referred to as WAVES (Women Accepted for Volunteer Emergency Service ) anymore - probably not. Arcing from motor armature brushes was a common cause of radio interference in the days of AM broadcasting, hence "brush discharge." Enjoy!
While a bit far-fetched, this Carl & Jerry saga from the June 1963 issue of Popular Electronics magazine has the two amateur radio hobbyists cum detectives applying their knowledge of standing waves and an invention called SNARE, "Signal Net for Actuating Radio-sensitive Explosives," by Irwin Ehlmann, to thwart an assassination attempt on a visiting foreign dignitary. The name of the patent is actually "Method and apparatus for detonating radio frequency sensitive blasting caps," but the principal is the same. The choice by author John T. Frye of a halo antenna on their mobile shortwave rig was probably no coincidence given the guardian angel role it played in the adventure...
On 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...
This Engineering Theme crossword puzzle for August 8th, 2021, contains only words and clues related to engineering, mathematics, chemistry, physics, and other technical words. 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., Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!