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Homepage Archive - June 2023 (page 2)

See Page 1 | 2 | 3 | 4 | of the June 2023 homepage archives.

Wednesday the 14th

Inventors of Radio: Sir Oliver Joseph Lodge

Inventors of Radio: Sir Oliver Joseph Lodge, August 1963 Radio-Electronics - RF CafeThe veracity of claim of ownership to many (maybe most) of the world's significant inventions is challenged either by others who seek credit, or by historians desiring to "set the record straight." In this 1963 Radio−Electronics "Inventors of Radio: Sir Oliver Joseph Lodge" article, author Dexter Bartlett says that Sir Lodge was the first to build a coherer, not Édouard Branly. Interestingly, Mr. Bartlett credits David Edward Hughes for the cohere prior to Branly as well. Maybe the Bartletts and the Branlys had a long-standing family feud going on, and he would sooner give credit to King George than to Branly ... but I digress. Sir Lodge had many notable accomplishments, including a tuned wireless telegraphy patent he sold to Marconi, portable antennas, and a triode detector circuit. See patent US609154A "Electric Telegraphy," granted May 21, 1901...

Buzz Aldrin Promoted to Brigadier General

Buzz Aldrin Promoted to Brigadier General - RF CafeApollo 11 astronaut Colonel Buzz Aldrin, the second man to ever stand on the moon's surface - and the first ever to photograph another man standing on the moon's surface - retired from the U.S. Air Force as a full bird colonel. As the result of a distinguished career as a fighter pilot and test pilot, and after earning a PhD in astronautics from MIT (thesis: "Line-of-sight guidance techniques for manned orbital rendezvous"), and after flying as an astronaut in NASA's Gemini space program, Buzz Aldrin was chosen as one of the three-member Apollo 11 crew (along with Neil Armstrong and Michael Collins). On May 5, 2023, at the Space Systems Command Los Angeles Air Force Base, Buzz was honorarily promoted to the rank of brigadier general (one-star) in the U.S. Space Command. Congratulations, Brigadier General Buzz Aldrin!

Mac's Radio Service Shop: Barney Talks A.C.-D.C.

Mac's Radio Service Shop: Barney Talks A.C.-D.C., September 1949 Radio & Television News - RF CafeHave you ever heard of a "globar" resistor? They have been around since the early days of radio and were used, among other things, to protect vacuum tube heater elements from burning up due to high inrush current when first turned on. Globars have a negative temperature coefficient (NTC) of resistance so that, opposite of standard carbon and metal film type resistors, they exhibit a higher resistance when cold than when hot. Mac and Barney discuss their use in this episode of "Mac's Radio Service Shop." You might be more familiar with the name "thermistor" for such devices, but globars are unique elements in that their construction from non-inductive ceramic material makes them useful at high power levels and high frequencies. Globar appears to now be owned by Kanthal (aka Kanthal Globar). Interestingly, Keysight Technologies (formerly Agilent Technologies, formerly Hewlett Packard) has an old Educator's Corner document where the student plots the resistance of a globar resistor against its temperature...

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 2018 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. An intro video takes you through the main features...

Thanks Again for Windfreak Technologies' Continued Support!

Windfreak TechnologiesWindfreak Technologies designs, manufactures, tests and sells high value USB powered and controlled radio frequency products such as RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters. Since the conception of WFT, we have introduced products that have been purchased by a wide range of customers, from hobbyists to education facilities to government agencies. Worldwide customers include Europe, Australia, and Asia. Please contact Windfreak today to learn how they might help you with your current project.

Tuesday the 13th

Mysticism in Output Matching

Mysticism in Output Matching, August 1963 Radio-Electronics - RF CafeTake note of the unique Smith Chart superimposed on the original soothsayer's crystal ball in this "Mysticism in Output Matching" article, which appeared in Radio-Electronics magazine. That is a rendition of the 3D Smith Chart* as developed by Dr. Andrei A. Muller and his team. Having only been recently created, the 3D Smith Chart was not around in 1963 when Herbert Ravenswood published his piece. In fact, although Phillip H. Smith's original Smith Chart had been around since 1939, it does not appear anywhere in the article. Mr. Ravenswood addresses the important difference between maximum power transfer and maximum efficiency of power transfer. Audio frequencies are specifically addressed (which might explain the absence of a Smith Chart) with regard to interfacing the output of a power amplifier to a speaker, but the concept is similar when dealing with RF frequencies. As with many articles on matching, the reactive part is not dealt with, so really it is an article on resistance matching, not impedance matching (unless there happens to be no reactive component)...

Dilbert on Trade Shows

Dilbert on Trade Shows - RF CafeBeing that the world's largest RF and microwave trade show, IMS2023 (International Microwave Symposium - see Exhibit Floor map) is happening this week in San Diego, CA, I thought this Dilbert™ comic strip from May 6, 2012, would be a fitting subject for posting on RF Cafe. Having been to a couple of the IMS shows and talking to exhibitors, many seem to actually relate to Dilbert's experience. The main value of having a presence there is often simply being seen in the realm of major players, which confers a certain level of industry gravitas. So, even if spending a week at the show does not directly result in new customers, at least some companies believe the cumulative effect of a persistent presence will pay off in the long run. At least one major RF/microwave manufacturer has concluded otherwise. Other Dilbert resources here...

Electronic Measurement Quiz

Electronic Measurement Quiz, January 1963 Popular Electronics - RF CafeThe early 1960s was evidently a good time for printing quizzes in electronics magazines. Popular Electronics was no exception. As I look through my collection I am finding quite a few. Here is the latest, from the January 1963 edition, that tests basic knowledge of using analog multimeters (digital types were not around yet). All are pretty straightforward; however, be careful with question 9. At first I thought maybe it was a trick question, but the key to arriving at the correct answer is noting that you are measuring a low resistance. Be sure to consider the properties of a standard multimeter of the era. Give it a try for yourself to see how well you fare. There was another Electronic Measurement Quiz in the August 1967 issue of Popular Electronics...

everythingRF Live Coverage of IMS2023 Show

everythingRF Live Coverage of IMS2023 ShoweverythingRF is providing live coverage of events at the IEEE's IMS2023 show in San Diego, from June 11th to 16th. The symposium will be conducting a technical conference along with a 3-day exhibition that includes 400+ exhibitors from around the world, showcasing their products and services. IMS is the flagship event in a week dedicated to all things microwaves and RF. The week also includes the IEEE MTT-S Radio Frequency Integrated Circuits Symposium (RFIC) and the Automatic Radio Frequency Techniques Group (ARFTG). IMS will hold a competition of the 50 top-ranked papers, as determined by the Technical Paper Review Committee (TPRC), that will be invited to submit their paper to the IEEE Microwave and Wireless Components Letters (MWCL) for publication. A floor plan of the Exhibit Hall is available here.

"Standing Waves on Transmission Lines

Standing Waves on Transmission Lines, December 1942 QST - RF CafeIn this article from a 1942 issue of QST magazine, author T.A. Gadwa employs a standing wave mechanism analogy that I don't recall having read before - that of a dam on a river. The river is the transmission line with a lake as the source (presumably) and then he imagines a dam load. The dam standing waves, per his description, have phase and amplitude characteristics that depend on how tall the dam wall is relative to the surface height of the dammed river. An extensive array of graphs is provided showing how the current of the dam standing waves react to the dam transmission line termination impedance. I always wonder when seeing electrical-mechanical parity examples whether, as with this case, there are any dam magazine articles out there that use an electrical transmission line to help fellow civil engineers...

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeNew Scheme rotates all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000 website 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. 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.

Thanks to Anritsu for Their Support!

Anritsu (electronics test equipment) - RF CafeAnritsu has been a global provider of innovative communications test and measurement solutions for more than 120 years. Anritsu manufactures a full line of innovative components and accessories for RF and Microwave Test and Measurement Equipment including attenuators & terminations; coaxial cables, connectors & adapters; o-scopes; power meters & sensors; signal generators; antenna, signal, spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth & WLAN testers; PIM testers; amplifiers; power dividers; antennas. "We've Got You Covered."

Monday the 12th

TV/FM Antennas Getting Bigger and Better

TV/FM Antennas Are Getting Bigger and Better, April 1968 Radio-Electronics - RF CafeTake a look at the variation in antenna design in the 1960s as presented in Radio-Electronics magazine. There was a boom in television and FM radio happening at the time, and antenna manufacturers were coming out with great new designs that promised to squeeze out that last little bit of signal reception and interference rejection. While fundamentally most of the antennas featured the standard array of straight, constant diameter reflector and radiator elements, many also incorporated fancy flat metal patches, spirals, and what resemble modern printed elements without the substrate. My guess it was mostly a combination of marketing hoopla and an effort to avoid patent infringements. There are not many TV and FM radio antenna models available today, but those that are generally don't have all the extra features. Some of the modern compact TV antennas made for receiving digital signals sport some fancy stuff, but they are fundamentally log periodic or Yagi design. Ham antennas typically do not have all the extra gimmicks, either. Aside from that, I have to acknowledge the amount of effort that went into illustrating all 30 of these antennas. A EM analysis of each using the latest modeling software...

In the Days of Spark - A Rescue at Sea

In the Days of Spark - A Rescue at Sea, November 1966 Popular Electronics - RF CafeWhen you think about wireless (radio) saving the day for reporting trouble at sea, most of us (including, until now, me) think of the RMS Titanic incident that occurred on 14 April, 1912. Her telegraph operator, Jack Phillips, managed to get off an SOS (actually "CQD" in the day) message that was picked up by the ship Carpathia. In fact, this story of the SS Republic recounts events on January 23, 1909 when the good ship collided with Italy's Florida. Radio operator Jack Binns managed to get off a CQD message using backup batteries once he discovered the ship's power had gone down. Jack Phillips had the dubious honor of gaining celebrity for his heroic action a few year after Jack Binns. If I were the owner of ocean-faring vessels in those times, I would be sure to always hire radio operators named Jack! Mr. Binns wrote the foreword to Allen Chapman's...

RF Cafe Sponsors at IMS 2023 in San Diego

RF Cafe Sponsors at IMS 2023 in San Diego, CA, Kirt's Cogitations #353 - RF CafeThe International Microwave Symposium (IMS) 2023, the RF, microwave, and wireless industry's premier trade show, is happening this week in San Diego, California. It runs from Sunday, June 11th, through Friday, June 16th at the San Diego Convention Center. Many of RF Cafe's generous sponsors have display booths set up on the Exhibit Floor. Their locations are labeled on the layout shown above. Clicking on the image will open a much larger version with legible print. While you are roaming, cruising, and perusing, please be sure to stop by and say hello to them and thank them for supporting RF Cafe. The matrix of company thumbnails on the left side represent all that are currently on RF Cafe, though some are not attending the show. BTW, be sure to see the Historical Exhibit for some amazing bits of our industry's development...

Notes on the Getter

Notes on the Getter, February 1958 Radio-Electronics - RF CafeIf you happen to be Estonian, you might think of something entirely different than most RF Cafe visitors do when we hear the word "getter." In fact, you probably capitalize the word since it is the name of a pop singer from your country, Getter Jaani. If you are a child living in Japan, you would probably think of Getter Robo, an anime from a popular cartoon series. I suspect just about everyone who visits RF Cafe knows getter as the silvery deposit (typically barium) that resides inside vacuum tubes for the purpose of helping to maintain the vacuum and to absorb pesky random molecules that might otherwise cause electrical noise in the circuit. This article from a 1958 edition of Radio-Electronics magazine discusses the purpose of getter. BTW, I had never heard of either of the other two Getters, probably due to OGS (old guy syndrome)...

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeNew Scheme rotates all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000 website 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. New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. If you need your company news to be seen, RF Cafe is the place to be.

Many Thanks to San Francisco Circuits for Continued Support!

San Francisco CircuitsSF Circuits' specialty is in the complex, advanced technology of PCB fabrication and assembly, producing high quality multi-layered PCBs from elaborate layouts. With them, you receive unparalleled technical expertise at competitive prices as well as the most progressive solutions available. Their customers request PCB production that is outside the capabilities of normal circuit board providers. Please take a moment to visit San Francisco Circuits today. "Printed Circuit Fabrication & Assembly with No Limit on Technology or Quantity."

Sunday the 11th

Electronics Theme Crossword for June 11th

Electronics Theme Crossword Puzzle for June 11th, 2023 - RF CafeThis custom RF Cafe electronics-themed crossword puzzle for June 11th contains words and clues which pertain exclusively to the subjects of electronics, science, physics, mechanics, engineering, power distribution, astronomy, chemistry, etc. If you do see names of people or places, they are intimately related to the aforementioned areas of study. Being that "K" is the 11th letter of the alphabet, it is used as the first and/or last letter of many words in today's crossword puzzle. As always, you will find no references to numbnut movie stars or fashion designers. Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds of them dating back to the year 2000. Enjoy.

Get Your Custom-Designed RF Cafe Gear!

Custom-Designed RF-Themed Cups, T-Shirts, Mouse Pads, Clocks (Cafe Press) - RF CafeThis assortment of custom-designed themes by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins, Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's" design has been ripped off by other people and used on their products, so please be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢ per item - Cafe Press gets the rest of your purchase price. These would make excellent gifts for husbands, wives, kids, significant others, and for handing out at company events or as rewards for excellent service. It's a great way to help support RF Cafe. Thanks...

Thanks to Alliance Test Equipment's for Support!

Allied Test Equipment Products - RF CafeAlliance Test Equipment sells used / refurbished test equipment and offers short- and long-term rentals. They also offer repair, maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP, Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization with ability to source hard to find equipment through our network of suppliers. Alliance Test will purchase your excess test equipment in large or small lots. Blog posts offer advice on application and use of a wide range of test equipment. Please visit Allied Test Equipment today to see how they can help your project.

Friday the 9th

Industry News Briefs

Industry News Briefs, April 1968 Radio-Electronics - RF Cafe"A battle is developing over spectrum space." That is the opening line in the News Briefs feature of Radio-Electronics magazine in 1968. Spectrum crowding then is peanuts compared today's airwaves. The Federal Communications Commission (FCC) began auctioning off spectrum in 1994 ("Auction 1"), selling space in the Narrowband Personal Communication Service (PCS) band. Since then, billions of dollars have been sucked out of the commercial sector (ultimately paid by private users). Governments have an insatiable appetite for Other People's Money (OPM, pronounced "opium"), and rule with the heavy-handed power authority of all federal enforcement agencies - including the military. The sunspot maximum for Solar Cycle 20 occurred around May 1969, with a monthly occurrence of 169. The NOAA chart shows Solar Cycle 20 is one of the longest on record but far from one of the most intense. The previous cycle peaked at 359 sunspots. We are currently on the upward side of Solar Cycle 25, with a peak thus far of 112 sunspots. It looks a lot like Cycle 24...

New Letter Contest for Servicemen

New Letter Contest for Servicemen, August 1944, Radio-Craft - RF CafeHallicrafters gave servicemen an opportunity to earn some cash by writing about their font line experiences using radio equipment built by Hallicrafters. The $100 top prize in 1944 is the equivalent of $1,705 in 2023 money (per the BLS Inflation Calculator) - not chump change in any year. Hallicrafters was a premier manufacturer of radios for commercial, hobby, and military use before World War II broke out. Once the United States was drawn in by the Imperial Japanese Navy's December 7, 1941 surprise attack on Pearl Harbor, no time was wasted converting the majority of production for electronics, transportation, and other realms into almost exclusively war production. Hallicrafters was, of course, onboard. Life took a sudden turn for many Americans as fathers, husbands, cousins, uncles, and brothers went off to fight battles in foreign lands. Communications to and from loved ones back home were difficult as priority was assigned to military channels, but that didn't discourage thousands of servicemen from writing letters during moments of discouragement or following victories. Many were penned from inside fox holes and bunkers, or even while riding in a C-47 on the way to being air dropped into a fire zone...

FCC Updates National Broadband Map

FCC Updates National Broadband Map - RF CafeNote "equity" vs. "equality" - a significant difference meaning a legally mandated result vs. an unbiased opportunity to achieve a result. Marxism vs. capitalism. The Federal Communications Commission has released an updated version of its National Broadband Map, one that FCC Chairwoman Jessica Rosenworcel said reflected a 'big' step in a new, iterative process that is meant to provide a more accurate and up-to-date picture of broadband access across the United States. This version of the map, as well as continued challenge-based refinements, will be used as the basis for state allocations from the massive Broadband Equity, Access, and Deployment (BEAD) funding program aimed at closing the digital divide, according to the National Telecommunications and Information Administration. The executive-branch agency added that it 'is confident that with this data as a baseline, we will be able to effectively allocate [BEAD] funds by the end of June. We will continue to monitor the FCC's updates to availability data to ensure that we make a well-informed allocation of these vital funds.' The FCC released what it called its 'pre-production' maps..."

Leeds "The Home of Radio" - NYC Radio Row

Leeds "The Home of RADIO" Advertisement, December 1931 QST - RF CafeLeeds, which dubbed itself "The Home of Radio," has been in New York since at least 1923. This advertisement appeared in the December 1931 edition of QST magazine. Leeds is still in operation today in Brooklyn under the name of Leeds Radio. They were one of the original "Radio Row" companies. Looking at the ad is a step back ninety years into the past, but the nostalgic waxing does not have to end there. If you want a trip back to the beginning days of the World Wide Web, go to the current Leeds Radio website. It's format-less text presentation with basic hyperlinks is circa 1992 when bulletin boards ruled the day and the Mosaic browser was just giving web surfers their first taste of a GUI. The only images I found on the Leeds website were a few scans of old advertisements...

RF & Electronics Symbols for Office™

RF & Electronics Schematic & Block Diagram Symbols for Office™ r2 - RF CafeIt was a lot of work, but I finally finished a version of the "RF & Electronics Schematic & Block Diagram Symbols" that works well with Microsoft Office™ programs Word™, Excel™, and Power Point™. This is an equivalent of the extensive set of amplifier, mixer, filter, switch, connector, waveguide, digital, analog, antenna, and other commonly used symbols for system block diagrams and schematics created for Visio™. Each of the 1,000 or so symbols was exported individually from Visio in the EMF file format, then imported into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or down without becoming pixelated, so all the shapes can be resized in a document and still look good. The imported symbols can also be UnGrouped into their original constituent parts for editing. Check them out!

Many Thanks to Reactel for Their Long-Time Support!

Reactel Filters - RF Cafe

Reactel has become one of the industry leaders in the design and manufacture of RF and microwave filters, diplexers, and sub-assemblies. They offer the generally known tubular, LC, cavity, and waveguide designs, as well as state of the art high performance suspended substrate models. Through a continuous process of research and development, they have established a full line of filters of filters of all types - lowpass, highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact Reactel today to see how they might help your project.

Thursday the 8th

Loral Distributor Products Hernia Relief

Loral Distributor Products, April 1968 Radio-Electronics - RF Cafe"Getting a hernia and not getting paid for it?" That's the lead question in this Loral Distributor Products ad in a 1968 issue of Radio−Electronics magazine. My response is to ask the obvious question: Are there actually people who do get paid for getting a hernia? Hernia repair† surgeons probably saw a lot of business from TV repair guys who did in-home service and had to lug sets from the truck to and from the house and shop. Even with using a hand truck the large console type TVs were a bear to move around. If you have seen some of the electronics themed comics from magazines of the era (I've posted hundreds of them), the often stressful life of mobile repair guys is a common topic. Loral doesn't offer a solution to boat-anchor-heavy TV sets, but they do claim using their capacitors will reduce the number of repeat service calls needed...

IPP's Online Interactive S-Parameter Viewer

IPP Announces Unique Online Interactive S-Parameter Viewer - RF CafeInnovative Power Products (IPP), with more than 30 years of experience designing & manufacturing RF & microwave passive components, is proud to announce its unique online Interactive S−Parameter Viewer! This one-of-a-kind online viewer allows you to scroll, zoom, point and select a sub-band. The viewer, still in beta, adds the flexibility of showing out-of-band data as well as the value at each data point just by hovering the cursor over the data point. Use the checkboxes to view individual S−Parameters, or choose to view by groups: All Transmission, All Reflection, All Isolation or All Parameters. You can view data in Log−Magnitude view, as a Smith Chart, or as Unwrapped Phase...

Atomic Radiation: Types & Relationships

Atomic Radiation: Types & Relationships, May 1969 Electronics World - RF CafeNuclear energy was a big topic in the 1960s and 1970s as it was believed to be the future of electrical power generation for the world (at least up until the 3 Mile Island, Chernobyl, and Fukushima incidents occurred). Ships and submarines were being powered by reactors that allowed them to run for months at a time without refueling, atmospheric emissions were practically zero, and the fuel source was abundant (albeit not simple to obtain). Medical and space applications were increasingly dependent on a greater knowledge of radiation and its effects on humans, plants, animals, and electronics. Many people by that time were working with and around radiation sources, so having knowledge of which is and is not safe was paramount to responsible activities. Proper operation of many types of equipment depend on adequate shielding from the effects of radiation. Probably the two major discriminators...

Gravitational Lensing Yields New Value for Hubble Constant

Gravitational Lensing of Supernova Yields New Value for Hubble Constant - RF CafeWho says that supergenius astrophysicists don't have a sense of humor? Certainly not me, and here's proof. A news story entitled "Gravitational Lensing of Supernova Yields New Value for Hubble Constant," tells an amazing account of how a group of researchers exploited the phenomenon of gravitational lensing (a relatively new discovery) by a recently discovered supernova to calculate a more accurate value for the Hubble constant (H0). Here's the hilarious part: One of the three primary research groups in the quest for ever-improved Hubble constant values calls itself H0LiCOW (H0 Lenses in COSMOGRAIL's Wellspring). "A study of how light from a distant supernova was gravitationally lensed as it travelled to Earth has been used to calculate a new value for the Hubble constant - an important parameter that describes the expansion of the universe ... The lumpy distribution of mass in the cluster created a complex gravitational field that sent the supernova's light along several different paths towards Earth. When the supernova was first observed in 2014, it appeared as four points of light. As the four points faded, a fifth appeared 376 days later. This light was delayed by the longer path it had taken through the cluster. During those 376 days the universe had expanded, which means that the wavelength of the late arriving light was redshifted..." Holy cow, another nonconstant constant!

Editorial - The Origin of "Ham"

Editorial - The Origin of "Ham", December 1931 QST - RF CafeHere it is the year 2023, a full 92 years after this editorial was published in ARRL's QST magazine, and nobody is any more certain of the origin of the term "Ham" being applied to amateur radio operators than they were in 1931. Being closer to the date of origin, though, might have given editor Kenneth Warner a bit more insight. In fact, the term Ham is usually uttered in a mildly pejorative manner; e.g., "he is such a ham." Per the QST's editor's research, Ham might be a shortening of Hamlet, referring to Shakespeare's play and the 2-bit actors who endlessly recited the lines in an attempt to impress others. Analogously, a Ham radio operator would be a professional broadcaster wannabe. However, Mr. Warner offers an even more plausible explanation that has the term descending more directly from the craft of amateur radio operation. Read on to find out...

RF & Electronics Symbols for Office™

RF & Electronics Schematic & Block Diagram Symbols for Office™ r2 - RF CafeIt was a lot of work, but I finally finished a version of the "RF & Electronics Schematic & Block Diagram Symbols" that works well with Microsoft Office™ programs Word™, Excel™, and Power Point™. This is an equivalent of the extensive set of amplifier, mixer, filter, switch, connector, waveguide, digital, analog, antenna, and other commonly used symbols for system block diagrams and schematics created for Visio™. Each of the 1,000 or so symbols was exported individually from Visio in the EMF file format, then imported into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or down without becoming pixelated, so all the shapes can be resized in a document and still look good. The imported symbols can also be UnGrouped into their original constituent parts for editing. Check them out!

Please Thank Werbel Microwave for Continued Support!

Werbel MicrowaveWerbel Microwave is a manufacturer of RF directional and bidirectional couplers (6 dB to 30 dB) and RF power dividers / combiners (2− to 16−way) with select models operating up to 26.5 GHz and 100 W of CW power (3 kW peak). All are RoHS and REACH compliant and are designed and manufactured in our Whippany, NJ, location. Custom products and private label service available. Please take a couple minutes to visit their website and see how Werbel Microwave can help you today.

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