1996 - 2016
BSEE - KB3UON
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...
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These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page.
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Please click here to view November 2014 homepage archive page 2.
Here is a batch of electronics-themed comics that appeared in the January 1945 edition of Radio News - a little light reading for you on a Friday afternoon. The editors must have been frisky and into the holiday spirit(s) when choosing comics that month. You'll see what I mean. There is a list of other comics at the bottom of the page.
Dan Bobyn, of Calgary, Alberta, Canada, wrote asking to be listed on the "Technical Services & Consulting" page of RF Cafe. Dan is an experienced engineer offering RF design consulting or contract expertise to small and large organizations across North America. Clients range from companies who don't have a full time RF design engineer, those who simply want an additional opinion on the RF design aspects of a particular project, to those who need additional hardware development resources to complete RF based projects outside their usual design engineering capabilities. Please call him today at 403-819-8464 if you have the need.
Pasternack Enterprises announces the release of their new 5 Bit, 8 Bit and 10 Bit broadband PIN diode digital step attenuators with performance up to 40 GHz depending on the configuration. These programmable, variable step attenuators are commonly used in electronic warfare, military and space communication systems, radar and test and measurement
So much time has passed since an average home garage mechanic could service his car or truck with standard tools - combination wrenches, screwdrivers, socket sets, timing light, and a multimeter - that asking "remember when?" is passé. That era pretty much ended in the late 1980s as computerized cars were becoming the industry norm. A good percentage of people nowadays have never and will never service their own vehicles. In the mid 1940s, the electronics world was lamenting a similar situation with diminishing ability to build and modify electronic components like coils …
I've never considered myself to be a class warfare guy, but facts are hard to ignore or deny when they are staring you in the face. Take this recent headline, for instance: "The 85 Richest People on the Planet Now Have as Much Money as the Poorest 3.5B." There are an estimated 7.2B people on Earth today, so that calculates to 0.0000012% of the people have as much combined wealth as 49% of the rest of the people. In engineering terms, that's 12 picopopulations vs. 490 millipopulations. We know the names of those top 85: Mexican communications magnate Carlos Slim Helu tops the list, …
Expectations and compliance willingness of employees and employers, respectively, have changed a lot since I first entered the workforce in the 1970s. At the time, at least for the companies I worked for as an electrician, the boss told you what to do and you did it. You showed up for work at a dictated time, worked hard all day with strictly prescribed break and lunch times, and quit at the end of your shift. Production line and office workers pretty much followed the same routine. I assumed everyone existed by the same rules. It wasn't until after I got out of the U.S. Air Force in 1982 and went to work for Westinghouse as an electronics technician that I witnessed the difference between the way …
Joe O'Neill wrote to request a listing for The Expert Institute on RF Cafe's "Expert Witnesses" services page. I agreed, and also, after perusing his company's website, I asked for and received permission to reproduce some of the short articles they have on topics relevant to RF Cafe visitors (that includes you). Stay tuned - the first of them will appear very soon. As with the articles written by IMS ExpertServices, I find case studies very interesting and informative since they represent real-world instances
- Optimizing Averaging
Better Power Measurements,
(p.28) Orwill Hawkins
- Determining the Best RF
Simulation Tools as an RF
- Using a Differential Probe to
- S-Parameters Basics,
- Measurement of an Active
Radar Module in a Compact
Antenna Test Range,
H. Shakhtour, D. Heberling,
K. Noujeim, F. Gerhardes,
and P. Knott
- Slot Antenna Tames 3 Wireless
Bands, C. Jianzhong,
W. Maowen, P. Wenjuan
The History Channel Presents The Best of Modern Marvels. These would make a good gift for your kids as inspiration to pursue careers in high tech - maybe even engineering. Did you see my recent post on the survey done on lifetime earnings expectations for various college degree majors? If the lad or lass doesn't plan to be a doctor or lawyer, engineering is definitely a good choice. The videos make a good gift for yourself as well, so start dropping hints in time for the Christmas shoppers.
"The fact that every part of this ship was built by the lowest bidder." That, according to Gene Kranz (NASA Flight Director during the Gemini and Apollo missions), was Alan Shepard's reply when asked what he thought about as he sat atop the Mercury Redstone rocket, waiting for liftoff. That fact that the boost vehicle, the Redstone, was originally designed as an expendable ballistic missile and not for safely launching humans into space might have had something to do with it, too. This 1957 vintage article …
Skyworks Solutions today reported Q4 and year-end results for the period ending October 3, 2014. Revenue for Q4 was $718.2 million, up 51% y-o-y and 22% sequentially, consistent with the updated outlook provided on October 14, 2014 and exceeding the Company's original guidance midpoint of $680 million. On a non-GAAP basis, operating income for Q4 FY2014 was up 81% from $130.3 million in Q4 FY2013. Non-GAAP diluted earnings per share for Q4 FY2014 was $1.12, including a $0.03 fiscal year-end tax benefit, compared to $0.64 for the prior year Q4.
Carbon button microphones were used in Alexander Graham Bell's first production model telephones. He bought the patent from inventor Emile Berliner because they were superior to Bell's own liquid element microphones. Condenser microphones followed, whose transducer element includes an integral variable capacitor. Interestingly, even though we in the U.S don't refer to capacitors as 'condensers' anymore, the name has persisted. Ribbon microphones are inexpensive …
"Sometimes, only one person is missing, and the whole world seems depopulated." - Alphonse de Lamartine, L'Isolement (a translation of 7th stanza), Méditations Poétiques (1820) -- to the families of fallen service members.
This Veterans Day (Remembrance Day in Canada and Australia) tribute is by Canadian citizen Terry Kelly. A Pittance of Time was written after an experience he had on Veterans Day in 1999. Terry went blind at an early age, but has excelled as an athlete and a musician. It is done in the finest Celtic tradition … and, of course, Lee Greenwood's- God Bless the USA , written 7 years before 9/11.
"Take two minutes, would you mind? It's a pittance of time, For the boys and the girls who go over. In peacetime our best still don battle dress, And lay their lives on the line. It's a pittance of time."
Not many people would argue that earning a college degree does not statistically portend higher lifetime earnings, and that the more degrees you have, the higher your income is likely to be. Sure, lots of people become very successful with little more than a high school diploma, but almost without exception they do it by starting their own business and figure out how to exploit their natural talents in a big way. You don't need a college degree to open a chain of auto lube stations, an electrical or plumbing contracting business, a lawn maintenance empire, or a few pizza parlors. Some do …
Not having a full collection of magazines is a real disadvantage when multiple part stories are published and some editions are missing. Such is the case here with Milton Kiver's series on electronics design. I do have other parts of the series, but they have not been posted on RF Cafe yet. However, each installment is pretty much independent of the others. This month's topic is on the fundamental theory of electrical potential and force. The name 'Maxwell' is mentioned, but not in the way that strikes fear in the heart of engineering students being introduced to the integral and differential forms of his eponymous equations (I know first-hand), so it's safe to keep reading. First semester physics books cover the same …
The arrival of 3D CAD programs has revolutionized the way the electronics industry is able to detect areas that have static interference within product parts. Backed by today's newest 3D software, advanced EMI/RFI shielding solutions by Orbel provide the protection required to successfully operate a piece of electronic equipment to FCC regulations.
The Good Life is a free publication printed in northern Michigan. Along with advertisements and stories from local interests, every edition is chock full of humorous quips and jokes. These (mostly) tech-related items are from the October 2014 edition. Sample: "There is a huge spider in my kitchen so I will be tweeting from on top of this table for whatever the life span of this species is."
What more could a company ask for than that someone would like his advertisements enough to reproduce them without collecting a fee and even encourage others to look at them? It's too late for my promotions to do the companies any good since most have long been out of business. World War II era ads stand out as a reflection on a largely unified country with a common goal of preserving its history and continuing its traditions (rather than that of a foreign conqueror) into the future. These ads from Bliley, Eastern Amplifier, and United Electronics are great examples.
Take a break and work this week's RF engineering themed crossword puzzle. All the words are pulled from a hand-built list of terms, names, and abbreviations that have only to do with science, mathematics, and engineering. If you want a crossword with names of movie stars and obscure countries, try the local newspaper. If you want to exercise your nerd knowledge, this is the one for you.
This week's additions to the collection of radio service data sheets are the Arvin Model 6 and the Emerson Model AZ-196 (Chassis AZ). Both appeared in the August 1938 edition of Radio Craft. As back in the era, similar schematic and service info was available for purchase from sources such as SAMS Photofacts, but these printings were a no-cost bonus for readers.
Now that the inestimable Bob Pease is no longer with us to enlighten and entertain, is there a contemporary and immediately recognizable electronics technology name you see on a magazine article, book, or presentation? Maybe my tech literary world is pretty small, but nobody come to mind as I write this (apologies to the many great authors I am forgetting). In the early part of the last century, you can be sure that when the names Edison, de Forest, Tesla, Marconi, Bell, and Morse were …
Many of your favorite magazines offer free subscriptions to qualified applicants. Qualified usually means that you are currently employed in a field related to the primary theme of the magazine, and often you also need to be a decision maker for buying products represented within the pages. Technical magazines, like RF Cafe, get paid by advertisers and therefore need the public to support those companies by purchasing their products and/or …
The high definition (HD) mode increases the vertical resolution of the Rhode & Schwarz RTO and RTE oscilloscopes to up to 16 bits - a 256-fold improvement over 8-bit resolution. Waveforms are sharper and show signal details that would otherwise be masked by noise. Input sensitivity of the oscilloscopes has been increased to 500 µV/div. Users benefit from even more precise analysis results.
You've heard of the World's Fairs, the most familiar probably being the 1933 Chicago World's Fair where the theme was "A Century of Progress." World's Fairs have been held in various cities worldwide since the late 1790s. In 1929, the World's Fair was held in the United Kingdom, but the "Radio World's Fair," which began its annual run in 1924, was held in New York City. Surprisingly little exists on the Internet about the events. It was more of a trade show to introduce new products than it was a fair, as can be seen …
Radio-controlled flying drones are commonplace today - so much so that the FAA has enacted legislation to strictly limit who can fly them, where they can be flown, how big they can be, what type of payloads can be carried, how far from the pilot they can be flown, etc. - the typical kind of overreaching and overregulating that governments promulgate (especially in the last few years). Sport model airplane flying has suffered loss of freedoms because of it by getting lumped in with multirotor drones. The military, of course, has been using …
Fairview Microwave Inc., a supplier of on-demand microwave and RF components, has launched its all new RF/Microwave eCommerce website featuring a powerful specification-based navigation, enhanced site search capabilities and a newly designed user interface. Fairview's redesigned website allows users to easily navigate through more than 30 RF product categories with its unique specification
Congratulations go out to Larry L. of Loogootee, IN, and Anthony P. of Russellville, AR, for being winners in the October RF Cafe Book Drawing. Not surprisingly, both guys chose to receive a free subscription to the Conquer Radio Frequency online course, by Dr. Francesco Fornetti. Graciously provided by Explore RF.
Hams like members of the Mogollon Rim Collins Collectors Club (K0CXX), play an important role in the preservation of vintage radio equipment. They own a nice example of a Collins model 30K-5 medium power (250 W) AM transmitter that is the subject of this 1946 article in Radio News. At 5½ feet tall and weighing 350 pounds, the 30K is many times the volume and weight of a modern solid state transmitter (transceiver + PA) having the same capability. Its advertised price in 1946 was …
Electrocution is no laughing matter, but I have to chuckle every time I look at the picture on my page that lists the human body's response to various levels of electrical current. The table shows that perceptible pain begins at around 10 mA and death can occur at 100 mA, which came to mind while reading an article in the July/August edition of Discover magazine titled "Why N0thing Works." Author Erik Vance reports on research being done on the effects of placebos (Latin for "I shall please") and nocebos ("I shall harm") in healing and pain suppression. Typically …
The Career Guide Book for Engineers, by John A. Hoschette. Currently, John is a technical director with Lockheed Martin in Eagan, Minnesota working on mission computers. His work encompasses developing the next generation mission computers for the F-35,P-3, F-16 and F-22 jet fighter aircraft. Building super computers that fly. His area of technical expertise is optical data networking.
This week's collection of employment and career related stories is a real mixed bag. Topics range from whether getting a Bachelor's degree is worth the time and expanse to when might be the best time in her career for a woman to have a baby. That just goes to show that there is an 'expert' on everything who is ready to give advice. My standard caveat stands: Just because someone managed to get an article published doesn't mean the advice is applicable you or anyone other than the writer.
Except under special circumstances, the FCC does not conduct much frequency monitoring activity. I know first-hand that even when a report of radio frequency interference is made to them, you will be told to figure out the source on your own and then get back to them. There have been a lot of news items lately where the FCC has levied heavy fines on Ham operators found to be in violation of the regs, and usually not because of independent complaints. This article from a 1956 edition of Popular Electronics relates some of the cases experienced by guys …
Anatech Electronics has released three new duplexer filter designs, one is a SAW duplexer covering the 1850.5-1909.5 MHz / 1930.5-1989.5 MHz bands, another is a cavity duplexer covering the 1164-1301 MHz / 1525-1612 MHz bands, and the last is a ceramic duplexer covering the 1190-1270 MHz / 1545-1625 MHz bands. All can be ordered directly through their AMCrf web store.
"The trouble with the world is that the stupid are cocksure and the intelligent full of doubt." - Bertrand Russell, in his autobiography, c1969
Before there were clocks that synchronized themselves to a wireless low frequency (LF) time standard emanating from one of NIST's broadcast towers, a different method was used to keep all the clocks in a building reading the same time. Many of the AC-powered mechanical master-slave clock systems are still in use today. This episode of Carl and Jerry has them teaming with a contract repairman to figure out why seemingly random clocks in their high school failed to synch with the master overnight. Author John T. Frye provides a pretty thorough overview of how the system operates using a power line carrier scheme. Of course the boys' keen …
FADA Radio and Electric Company, of Long Island, New York, had a unique message for veterans returning from the throes of World War II. Rather than focus on the potential loss of 'innocence' caused by exposure both to the horrors of war and the excitement and splendor of foreign cities, it appealed to a desire to forget about the glitz and glitter and come back home to help America convert its amazing technical and manufacturing base, borne out of desperate wartime need, into a thriving postwar, commercial economy. Many …
One of my favorite old-time radio personalities, Paul Harvey, had a trademarked feature titled The Rest of the Story. For those of you not familiar with the format, Mr. Harvey would begin his story talking about particular life aspects of a person that, while remarkable, usually had no connection with the person's eventual claim to fame. The listener's challenge was to guess who the person was before it was revealed at the very end, followed by, "... now you know --- the rest of the story." As far as I know the story of FM radio inventor Edwin H. Armstrong was never a subject, although it certainly met the criterion. I've already let the figurative cat out of the bag, so …
Edward Weston was a pioneer in the photoelectric cell field. His 'photronic' cell was one of the first successful devices for commercial use. Just like with early battery cells, photoelectric cells of the era required a liquid medium to facilitate electron transfer and thereby generate electric current. The lead nitrate compound used by Weston is now considered a possible human carcinogen. Mr. Brooke Clark has a web page with extensive data on the history of Weston's photoelectric sensors, meters, test data, patents, and history of his …
As promised last week, this crossword puzzle's theme is engineering book authors. If you follow contemporary technical books on amplifier and filter design, radar systems and component design, then there's a good chance you will recognize these guys. There are no gals in the list; however, there is one very famous lady who is credited with giving birth to the concept of broadband frequency hopping spread spectrum communications. Ooooh (smacks own forehead) ... will the phrasing of that last sentence have me sleeping on the couch tonight, figuratively? (doh!, did it again)