RF Cafe Software
About RF Cafe
1996 - 2022
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 items are an archive of past Topical Smorgasbord items that have appeared on the RF Cafe homepage. In keeping with the "cafe" genre, these tidbits of information are truly a smorgasbord of topics. They all pertain to topics that are related to the general engineering and science theme of RF Cafe. Note: There is also a huge collection of my 'Factoids' (aka 'Kirt's Cogitations') that might interest you as well.
Call Me KB3UON/AE - Amateur Extra License Exam Passed!
Woo-hoo, I have finally achieved Ham radio license Nirvana! Reporting this on World Amateur Radio Day seems appropriate. On Saturday, April 15, 2017, I passed my Amateur Extra exam in the presence of three VEs at the Wattsburg Wireless Association meeting room in Erie, PA. Nearly 7 years have transpired since I took the Technician test in the same room in 2010. My General license test was taken Forsyth Amateur Radio Club meeting room in Winston Salem, NC, in, 2015. Until the FCC updates my record in the online Universal Licensing System (ULS), my call sign will be KB3UON/AE. Motivation for pursuing the Ham radio license goal was ...
Therapeutic Radio, by Marek Klemes
Proud Canadian and RF Cafe contributor Dr. Marek Klemes wrote to me a couple weeks ago regarding a quotation I had posted a while back. At the end of our communications, he casually made a comment about needing to engage in an electronics project that would be free of the rigors of his professional pursuits. Being a trained notable quote recognizer myself, I instantly realized that his statement was itself worthy of being quoted widely. He granted permission to post it here (with adornment of ...
Domain Name Valuation per Online Estimators
As mentioned in the past, I put a fair amount of effort into making RF Cafe as user friendly and resourceful as possible while also providing a valuable venue for RF product and services companies to advertise. Reading articles on search engine optimization, effective user interface and user experience, webpage organization, navigation, page load speed and content organization are popular topics that the 'experts' have decided are most important to success. My ultimate philosophy has been to make RF Cafe the kind of website I enjoy visiting. A piece ...
"Radio and the People's Railway", Classic Trains Magazine
RF Cafe visitor and frequent e-mailer Joe Birsa (N3TTE) sent a note saying that the Spring 2017 issue of Classic Trains magazine contains an article titled "Radio and the People's Railway," by Greg Gormick. I do not have a copy on-hand, so I went to Wikipedia for some information on the Canadian National Railways Radio Department, where it says in part: "The Canadian National Railways Radio Department was the first national radio network in North America. It was developed, owned and operated by the Canadian National Railway between 1923 ..."
Neil Carlton's (VE3NCE) Radio Stamp Collection
As you might expect, Ham radio operators tend to be the type of people who engage in more than one pastime. Many are handy with tools and like doing challenging home improvement projects and renovations of cars, trucks or antique furniture. Others enjoy hobbies like flying model airplanes and/or rockets, boating, fishing, baseball, and other endeavors of skill and prowess. Some, like Canadian amateur radio operator Neil Carlton (VE3NCE), count stamp collecting amongst their extracurricular activities. Stamp collectors are known properly as philatelists. Neil does not collect just any kind ...
Sputnik Watch in Erie, Pennsylvania
The Space Race officially began on October 4, 1957, when the USSR successfully launched Sputnik 1, the world's first Earth-orbiting communications satellite. It was a big deal. The 'bird' transmitted a continuous alternate series of pulses at 20.005 MHz and 40.002 MHz, with a 300 ms on and 300 ms off time. The batteries lasted through October 26. Sputnik 1 burned up in the atmosphere on January 4, 1958. Radio monitoring stations all across the Earth scrambled to detect and track Sputnik 1's signals while noting signal strength, frequency stability ...
The Broken U.S. Patent System - Kirt's Cogitations™ #277
The U.S. Patent and Trademark Office (USPTO) is constantly advertising for examiners. Its workload is overwhelming and the consequences are significant. Based on information on an extremely well-written and researched article in the July/August 2016 issue of Popular Mechanics magazine titled "The Greatest American Invention," the situation is practically out of control. Similar to many other pieces published in the last few years, author Scott Eden meticulously outlines the systematic failures of the current patent bureaucracy and how, as is typical, mostly unqualified lawmakers in an attempt to 'reform' it pass regulations that make matters ...
2017 Obamacare Cost for RF Cafe - Kirt's Cogitations™ #276
You might have heard that Obamacare rates are WAAAY up for 2017. Being self-employed in Pennsylvania, the cost for bottom-end (Bronze) plan for Melanie and me in 2017 is $772.28/mo. ($9,267.36/yr.) + $13,900 deductible. That's $23,167.36 out-of-pocket before Obamacare pays anything at all, and then only 60% of fees after full deductible has been paid. Check it out on healthcare.gov . Oh, and if I want to keep my current doctor, that plan this year is $974.75/mo. + $13,900 deductible ($25,597.00/yr.). It does NOT pay for emergency room, diagnostic, x-ray, MRI, etc., until AFTER the deductible has been paid ...
Is Your Domain Being Blocked by a Country?
Recently, a company based in China contacted me about advertising on RF Cafe. After doing a lot of up-front work for them creating advertising materials, the representative informed me that he cannot access the RFCafe.com domain from his location. It is really difficult to conduct business when the customer cannot review your work, so at least for now, I am going to pass on the opportunity. The obvious question that arises from the experience is whether RFCafe.com is being blocked by China, and how do I find out? Fortunately, a few options exist with websites that will perform the check for you by pinging your URL from servers within multiple countries. Some, such as GreatFirewallOfChina.org, tests from inside China using servers in Beijing ...
Under a Telephone Pole, by Carl Sandburg
"There is no new thing under the sun." "Everything old is new again." Many such idioms exist regarding how often things tend to run in cycles; it's just that often times people who think they are witnessing a new phenomenon are not aware of the previous occurrences. I have written of examples where 'old timers' lament the attitudes of a fledgling work force when writings show the previous generation of 'old timers' who worked with the current 'old timers' in their youth expressed the same type concern. Experienced Ham operators think newbies cannot carry on the tradition of wireless because they are not required to learn Morse code anymore to earn a license. An article titled "OMG! We've Been Here B4," appeared in the March 2016 issue of Smithsonian magazine ...
Anyone Else Remember Calling WE6-1212 and TI4-1212?
Long before there was a World Wide Web for getting the latest weather report and the local time for setting your clocks, there were phone numbers that were set up with recordings of the sought after information. As a kid in the 1960s and 1970s, I called the weather forecast number, WE6-1212 ('WE' for weather), multiple times daily during the winter in hopes of hearing a forecast for snow, and during the summer in hopes of favorable conditions for flying model airplanes and launching Estes rockets. An obsession with time and watches and clocks had me calling the time phone number, TI4-1212 ('TI' for time), so often that my father used to refer to the lady on the recording that updated ...
Able Signal Amplified Digital Outdoor HDTV Antenna Installation
Since I do not have time to watch television on a regular basis, paying for a cable or satellite subscription cannot be justified. My plan was to install a traditional FM/VHF/UHF television antenna on the roof along with a rotator. Some pretty models are still available from Channel Master, RCA, and a few others. TV broadcast stations in the Erie area are all within 10 miles or so, so signal strength would not be an issue. I listen to both AM and FM radio most of the day, so being able to get an FM signal boost from a steerable antenna would be a nice bonus since occasionally reorienting the FM dipole was needed to get a clear signal. The entire outfit would cost less than a year's ...
Makerspaces & Maker Faires
DIY (do-it-yourself) is the relatively new term adopted to describe any activity engaged in by laymen and even professionals plying their trades after hours. Subjects range from hanging a kitchen cabinet or planting a tree, to a total engine rebuild or building a robot. Reasonable quality and capability tools for performing around-the-house chores are fairly cheap and available for purchase or rent for projects most people undertaking such challenges. Cordless saws and drills, stud finders, airless paint sprayers, and electronic readout levels can be had for under ...
Challenges in Early Automotive Radio Design
Early automobiles presented significant challenges to mobile radio designers due to a combination of a fledgling understanding of electrical and electronic circuits and quickly evolving automotive materials and configurations. A 1935 issue of Radio-Craft magazine presented eight automotive radio designs that represented break-through techniques for dealing with some of those innovations. All of the technical issues involved here have been pretty much solved in modern radios. Ignition interference is nearly invisible to FM and satellite reception, although audio frequency circuits can still pick up noise is not properly filtered ...
The Periodic Table of Substitute Performance
In a Scientific American article titled "Elemental Urgency," Jennifer Hackett reported on a paper published in 2013 by Yale University's Thomas Graedel et al regarding the availability (or unavailability) of the raw elements - and suitable substitutes - used extensively in modern manufacturing. Unlike half a century ago when most products were made from relatively common and easily obtainable elements like lead, iron, tin, nickel, aluminum, carbon, zinc, silicon, and even silver and gold, many more elements are now regularly included in mass manufacturing processes. Rhenium (Re), used in high strength, temperature alloys ...
The Concinnitas Project
The January 2016 issue of Scientific American ran an article by Clara Moskowitz titled "Elegant Equations" that presented a few prints from "The Concinnitas Project" which "...is a collection of ten aquatints produced from the contributions of ten mathematicians and physicists in response to the prompt to transcribe their 'most beautiful mathematical expression.'" My personal favorite is "Ampère's Law," by Simon Donaldson, because it incorporates a simple line drawing along with the familiar equations. It brings back memories of sitting in electromagnetics class at the University of Vermont watching my seriously brilliant professor (no kidding), Dr. Kenneth Golden, draw ...
You've Heard of a Copyright, But How About a Copyleft?
No, this is not a liberal vs. conservative thing, although you might be tempted to think so when considering the terms of each. A copyright, as you know, is legal protection against unauthorized usage or obvious modification of original works, something a right-winger would like because it represents a right to private property. A copyleft, on the other hand, is a left-winger's dream because it permits free distribution of original works with the only restriction being that it and/or derivative works also be declared copyleft material. That explains why evil capitalist companies like IBM copyright and patent everything it creates, and why liberal-dominated companies like ...
Tesseract Antique Instruments
My introduction to a tesseract was during an episode of Carl Sagan's "Cosmos" series in the 1980s, where he was demonstrating how beings in of dimension N would perceive items of dimension N+1. The tesseract, Sagan explained, is a 3-dimensional projection of 4-dimension hypercube. Watch the embedded video for more information. The Tesseract website, which has nothing to do with a hypercube as far as I can tell, deals in some very cool antique scientific instruments. I learned of it from an article in Astronomy magazine where an editor recommended it when researching the potential value of a collectible telescope. Run by Drs. David and Yola Coffeen, Tesseract has a huge inventory of items ...
The "Fair Use" Doctrine and the U.S. Copyright Office
"The Congress shall have Power … To promote the Progress of Science and useful Arts, by securing for limited Tımes to Authors and Inventors the exclusive Right to their respective Writings and Discoveries." - United States Constitution, Article I, Section 8. Therein lies the authority for legislation and prosecution of rights for virtually every human creation within the jurisdiction of the country. Each nation has it own version, and international agreements help assure universal protection of a creator's rights of ownership; e.g., the "Convention for the Protection of Literary and Artistic Works" of 1886 and the World Intellectual Property Organization. America has the U.S. Copyright Office. Those of us involved in presenting information and referring to legally protected ...
Google Interview Questions
Questions asked by interviewers at Google are objects of much ballyhoo. Depending on the job being sought, questions range from relatively simple and objective to massively esoteric and subjective. Perform a search on "Google Interview Questions" and you will find a host of websites that collect experiences from recent interviewees. Some people curse Google for their insanely difficult questions, but what is fundamentally a form of profiling and discrimination is what provides Google with exactly the employees they need to be at the leading edge of all sorts of technology - networking, software, hardware, publishing, website design, social media, global politics, search optimization, etc. As you can see, many questions require the interviewee to state assumptions and conditions prior to asserting a solution. For instance, "Estimate the number of tennis balls that can fit into a plane" has no single answer because while the size of a tennis ball ...
RF Cafe Now Has Google's 'Mobile-Friendly' Blessing
Many format changes to RF Cafe have occurred since its inception in 1999, primarily to optimize the layout and content for presentation to my targeted audience - engineers, technicians, hobbyists, managers, and salesmen who make a living and/or pastime of electronics. This latest format change, however, comes in response to Google deciding to penalize website search ranking for any page or pages that do not pass its Mobile-Friendly Test. With 2/3 of the world's search business, they set the rules. If a page is not deemed Mobile-Friendly, it will likely be demoted to a lower spot on the search result page compared to if it was compliant. In some cases a website that would ...
February 15, 2016
"It's Déjà Vu All Over Again"
That is probably Yogi Berra's most famous line, and is the first thing that came to mind today when I read in the local newspaper where GE Transportation here in Erie, Pennsylvania, plans to layoff 950 production and 100 management employees. An additional 200 "temporary" layoffs could also occur. Rumors have been in the works for a couple years regarding an eventual total plant closing, since a new plant with the same capability (and more) was being established in Fort Worth, Texas. The Erie location is totally unionized, and Texas is a Right-to-Work state (union membership not mandatory). In an effort to be "globally competitive," labor rates must be kept as low as possible - for everyone, not just production workers. Texas also has no income tax, which helps keep wages low as well. Property taxes in Erie are quite high, typical of the Northeast...
FITSAT-1 CubeSat Flight over Erie, Pennsylvania
I stayed up late last night (early this morning, actually) to watch the FITSAT-1 CubeSat satellite flash its Morse code "HI DE NIWAKA JAPAN" message via super-bright LEDs over eastern North America. It was scheduled to pass just south of my location in Erie, Pennsylvania, at 1:14 AM, with a lights-on intensity great enough to be easily seen with binoculars. FITSAT-1 is a project conceived of and built by professors and students at the Fukuoka Institute of Technology (FIT) in Japan. In addition to the LED visual display, the satellite also carries several Amateur Radio payloads including a CW beacon on 437.250 MHz, a telemetry beacon on 437.445 MHz and a high-speed data downlink on 5,840.0 MHz. The CubeSat Project was developed by California Polytechnic State University and Stanford University's Space Systems Development Lab. It creates launch opportunities for universities previously unable to access space. A CubeSat...12/12/2012
Learn Almost Anything for Free"Learn almost anything for free." That is the tag line of the Khan Academy. While the claim is a bit of a stretch, especially when you need to delve below surface level, they do have over 3,300 videos on everything from math to physics, finance, and history. According to their website, in August 2004, Sal Khan began remotely tutoring his cousin, Nadia, who was struggling with unit conversion. Soon, Sal also began tutoring her brothers as well. He became so popular that he started recording videos and posting them on YouTube. More and more people kept watching, and Sal has continued to make videos ever since. Khan eventually drew the attention of Google ($2 million grant) and Bill Gates ($1.5 million grant). The rest, as the saying goes, is history. RF Cafe visitors might be particularly interested in subjects like circuit analysis (4 lessons), capacitance, magnetism (12 lessons), electric motors, electrostatics, Doppler, optics, and fields. You might also like watching the video lessons on momentum and torque, friction, gravity, thermodynamics (5 lessons), Newton's laws , and fluids (12 parts)...
Tax Day 2013: RF Cafe's *Fair Share*
Tax Freedom Day for this year is April 18 - five days later than last year. Today, April 15, is the day in America by which half the population gets to pay its *fair share* to the government in the form of income taxes (the other half pays no income taxes). Oh, excuse me, it is when we are "asked" to pay our fair share. Don't you love the "asked" term ...as if we have the option of refusing without going to jail? Six envelopes are pictured here that contain various tax mailings for Melanie and me: one each to the IRS for income tax and Q1 estimated income tax, state income tax and Q1 estimated income tax, local income tax and estimated income tax, plus a local services tax. The local services tax is just for the 'privilege' of working - I kid you not. After paying federal, state, and local income taxes, sales taxes on all we bought (including gasoline), utility taxes, taxes on savings, property taxes, school taxes, etc., etc., etc., our total 'fair share' works out to 37.6% on adjusted gross income. So, more than a third of my income was paid in taxes. Just our federal adjusted gross tax alone worked out to 26.6% of adjusted gross. By comparison, according to Whitehouse.gov, "The President's effective  federal [adjusted gross] income tax rate is 18.4%..."
PartSim Online Analog Circuit Simulator
Simulation Program with Integrated Circuit Emphasis (SPICE) has been around since 1973. The basic computational engine has always been open source. It began as a simple analog circuit simulator that took a structured text file as the input net list and provided a text file output that contained the calculated values that the user specified such as DC bias points, transient analysis, and AC analysis. Component models started with relatively simple definitions. If you wanted a graph of the response, it was in the form of text characters with a standard 80-column division on the y-axis and the x-axis was as many divisions as it needed to be to cover all the points calculated (often printed out on fan-fold paper in a pin printer). Yes, I personally used those versions in the mid 1980s. As time progressed, improvements were added to the computational engine to handle a wider range of component models including digital and RF/microwave. More parameters were added to component models to yield a better agreement between simulation and laboratory measurements. Lagging...12/20/2012
Is a Picture Still Worth a Thousand Words?
The old adage about a picture being worth a thousand words is
validated often with charts and graphs made for science, engineering, and finance. This chart illustrates
levels of collaboration between 25 countries on scientific papers published in 2011 in a select group
of journals. Author John Sexton uses color and line width to indicate origin and volume between countries.
Circumferential length is relative volume overall. He also includes a similar chart showing internal
collaboration within the 10 countries with the highest scientific paper output. Per Mr. Sexton, in 1996
about 25% of scientific articles were authored by people in two or more countries; today it is 35%.
Non-commercial "Big Science" projects like the Large Hadron Collider (LHC) at CERN, with multinational
funding, contribute largely to the increase. Aptly pointed out is how global access to and...
RF Cafe Communications Central
How much do you pay every month for all of your personal communications? That includes, but is not limited to, smartphones with data plans, land lines, Internet, cable TV or satellite TV, wireless tablets and computers. Life in 2013 practically requires some degree of connectivity, but many people are paying for way more of it than necessary. I absolutely need a high speed Internet connection because of publishing RF Cafe (14 Mbps for $44.90 per month). Since most of my personal communications are via e-mail, phone service is not a high priority so my cell phone is a TracFone that I pay under $100 per year to use (mainly when away from home). Since there is no time for TV, any watching is done via the Internet - it doesn't matter if shows are a week or month old - so no cost there. I like using an old-fashioned telephone with a handset at home, so a landline is also used. Up until a couple months ago I was paying the local phone company $27 per month for basic local service (no long distance, caller ID, messaging, etc.).
How to Draw a Circle with a Square
"Squaring the circle" may as yet be an unattainable goal for even
the best mathematicians, but the November 2012 edition of The Family Handyman magazine had a tip for
how to use a square (of the framing type) and two nails draw a circle. This is what it
said: "Make a Circle with
a Square - Here's a tip for laying out small circles or parts of circles. Tack two nails to set
the diameter you want, then rotate a framing square against the nails while you hold a pencil in the
corner of the square. You might need to rub a little wax or some other lubricant on the bottom of the
square so it slides easily. Don't ask us why this process works; all we know is that it does." They're
either very honest or they don't think the average reader would understand the explanation. The Pythagorean
theorem is the key, of course, for explaining the reason. For any right triangle: a2 + b2 = c2, where 'a' and 'b' are the lengths of the two perpendicular sides,
and 'c' is the length of the hypotenuse...
PartSim Online Analog Circuit Simulator
Each year the Foundational Questions Institute (FQXi) holds an
essay contest inviting writers to submit missives addressing the question chosen by the FQXi board as
being particularly thought-provoking. In their words, "FQXi catalyzes, supports, and disseminates research
on questions at the foundations of physics and cosmology, particularly new frontiers and innovative
ideas integral to a deep understanding of reality, but unlikely to be supported by conventional funding
sources." The 2011 question was "Is Reality Digital or Analog?" Scientific American magazine,
being one of three partners, published the runner-up entry in the December 2012 issue: University of
Cambridge professor of theoretical physics professor David Tong's paper argues that the world is in
fact fundamentally analog.
Professor Tong actually tied for second place, but for some reason SciAm does not tell us whether the other second place paper supported an analog or digital viewpoint. For that matter, it did not say which side the winning paper came down on. Strange. I looked it up on the FQXi website. First place went to Jarmo Makela, who believes reality is digital in nature based on a personal discussion with Isaac Newton in his London home in the year 1700. When...
What's Fair About an Internet Sales Tax?
You have probably heard and/or seen the scuttlebutt about Congress trying to push through an Internet sales tax, ostensibly in order to level the playing field for brick and mortar businesses versus online businesses. You can be sure the effort has nothing to do with fairness and everything to do with politicians' insatiable appetite for tax money. They have been salivating over the possibility of reaping that new revenue source for years. The plan is to require online sales from out-of-state buyers to have sales tax collected and remitted to the appropriate state revenue department. Local businesses are per the claim disadvantaged because they must collect their home state's sales tax, which supposedly causes buyers to prefer Internet vendors in order to avoid such taxes. As one who has purchased many items over the Internet in the last 15 years, I can't think of many times when avoiding sales tax was the prime motivation for my decision. It was usually because either the item I wanted was not...
What Does Your Daily Commute Cost You?
far do you commute each day for the privilege of doing your part to push back the frontiers of technical
ignorance and to boldly go where no engineer - or technician - has gone before (split infinitive by
Roddenberry, not me)? Do
you know what the cost equates to you each year? This handy-dandy poster by the folks at Streamline
Refinance lays out some gruesome numbers. Those with a weak stomach probably should pass on viewing
this one. Here's a hint at what you will see: See that big $795 in the thumbnail image? That's the average
cost per year for commuting -- per mile! Yessiree,
if you live just 10 miles from work, you're losing nearly $8k per year, depending on you automobile
type, on gas, tires, maintenance, devaluation, and loss of your personal time (which is valuable,
after all). Back in the early 1990s I drove 45 miles each way to Comsat, which took about 65
minutes due to miserable traffic. That's 130 minutes round-trip, or 2 hours and 10 minutes
(about the run time of an average movie) each day. Figuring two weeks vacation and
10 holidays, that leave 48 weeks x 5 days/week = 240 days per year of commuting. 240 days...
PartSim Online Analog Circuit Simulator
while sitting in the studio where Melanie takes her cello and piano lessons, I usually read technical
and hobby magazines, but lately I have been studying the ARRL General Class License Manual
in preparation for taking the written exam in a couple months. Last week a lady saw the book title and
remarked, "I didn't know
ham radio people were still around." Wow. It would be tempting to blame her for being
ignorant, or to blame the ARRL (American Radio Relay League) for not adequately getting the word out,
but the reality is that the mass media does not consider Ham radio's contribution to be significant
enough to cover in news stories. Amateur radio operators perform a mighty service in times of trouble,
but they do it so efficiently and effectively- without actively seeking credit - that their efforts
are lost in the noise. Ham radio operators have been on the front lines of national and civil defense
since World War II and even a bit before...