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Tech Smorgasbord Archives - 34

RF Cafe University"Factoids," "Kirt's Cogitations," and "Tech Topics Smorgasbord" are all manifestations of my ranting on various subjects relevant (usually) to the overall RF Cafe theme. All may be accessed on these pages:

 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37

Call Me KB3UON/AE - Amateur Extra License Exam Passed! - #283

Call Me KB3UON/AE - Amateur Extra License Exam Passed!, Kirt's Cogitations #283 - RF CafeWoo-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 - #282

Therapeutic Radio, by Marek Klemes, Kirt's Cogitations #282 - RF CafeIs this an über-cool homebuilt radio or what?

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 - #281

Domain Name Valuation per Online Estimators - RF CafeAs 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 - #280

Radio and the People's Railway, Classic Trains - RF CafeRF 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 - #279

Neil Carlton's (VE3NCE) Radio Stamp Collection, Kirt's Cogitation #279 - RF CafeAs 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 - #278

Sputnik Watch in Erie, Pennsylvania - RF CafeThe 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 Broken U.S. Patent System - RF CafeThe 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

Thanks, Fellow Citizens, for Obamacare! - RF CafeYou 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? - #275

How to Test Whether Your Domain Is Being Blocked by a Country, Kirt's Cogitation #275 - RF CafeRecently, 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 - #274

Under a Telephone Pole, by Carl Sandburg - RF Cafe"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 ... 


Defeating AdBlock Plus™ - #273

Defeating AdBlock Plus™ - RF CafeAs someone who spends a lot of time surfing the Web in search of interesting electronics and technical news, I am painfully aware of the annoyances caused by intrusive, overwhelming advertisements. The most detestable are the full-screen ads that get in your face before ever seeing the webpage, and/or once on the page some cursed ad with video and audio plays automatically. It is no wonder that an exponentially increasing portion of Internet users are employing ad blocking software. If you are an advertiser paying for proprietary representation on a website, you are advised to determine whether your ads can be blocked. ...

All Elements Heavier Than Helium Are Metals? - #272

Metallicity - RF CafeFactoid: Astronomers consider all elements heavier than helium to be metals. That definition obviously does not jive with the standard chemical definition of a metal, but a concept called 'metallicity' argues that from a star (and therefore the universe) formation perspective, extremely high temperatures and pressures in first generation stars (like our sun) preclude the identification of distinct elements other than hydrogen and helium. Heavier elements, such as lithium - #3 on the periodic chart and actually considered a metal in ...

X-Microwave™ Block-Level Prototyping System - #271

X-Microwave™ Block-Level Prototyping System - RF CafeIn case you don't already know, a grown-up's version of the much-ballyhooed littleBits electronics building block system is available. Instead of assembling snap-together functional blocks for making LEDs flash or robotic carts, X-Microwave's system provides a relatively simple and inexpensive venue for designing and building RF and microwave circuits based on a selection of component blocks for frequencies ranging from hundreds of kHz to tens of GHz. As you can see in the X-Microwave video, functional blocks are screwed to a base plate with optimized interconnects providing low-VSWR, low-loss interfaces between blocks. Package sides, isolation compartment walls, and lids complete the system package with coaxial connectors at the I/O ports ...

1st Mention of Electric Light in The New York Times - #270

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

The Shive Wave Machine - #269

The Shive Wave Machine, Bell Telephone Labs - RF CafeSometime around 1985, I was enrolled in a second-semester physics class while working on earning my BSEE. Along with covering topics like electricity, magnetism, heat conduction, optics, etc., my professor, a moonlighting oceanography instructor from the nearby U.S. Naval Academy, conducted a laboratory exercise wherein he wanted to demonstrate the action of sea waves breaking against the shore and underwater shelf discontinuities. He used an impressive contraption that was comprised of coplanar parallel metal rods that were attached in their centers to a spring steel bar for torsional continuity. The tips of the rods were painted white so that when the end bar was perturbed ...

IEEE MTT-S Buys Rights to Smith Chart - #268

IEEE MTT-S Buys Rights to Smith Chart - RF CafeSomehow, even with trolling daily for technical headlines, I managed to miss (until recently) that back in April of this year, IEEE's Microwave Theory and Techniques Society (MTT-S) acquired the copyright to Phillip Smith's legendary eponymous graphing format: the Smith Chart. Per a column by 2015 IEEE president Tim Lee in the Xplore publication: Mr. Tim Lee, IEEE's 2015 president. "In 2015, the MTT-S had the opportunity to meet with Mrs. Anita Smith and her family and propose a way to preserve the legacy of her husband and their father. The MTT-S offered to buy the rights from the Smith family of the Smith trademark belonging to Analog Instruments, along with the copyright. In return, the MTT-S would make the Smith chart available to students, practitioners, and indeed people all over the world involved ...

Drone' Registration with the FAA Begins Today - #267

'Drone' Registration with the FAA Begins Today - RF CafeActually, the title of this and other news stories is very misleading regarding exactly what has to be registered. The generally uninformed or marginally informed public believes the definition of a 'drone' is anything that flies without a human pilot in the cockpit. It associates the greatly dramatized and sensationalized reports of public encounters with what are technically classified as Unmanned Aerial Systems (UAS) - multirotor copters. These are for the most part the variety sold in toy stores ranging in cost and complexity from $50 for a basic 4-propeller 'quadcopter' to $500 for a 6-propeller model with an onboard camera and maybe even a First Person View (FPV) wireless system that allows the pilot to fly from a vantage point on the craft while remaining at a remote ...

Anyone Else Remember Calling WE6-1212 and TI4-1212?

Anyone Remember Calling WE6-1212 and TI4-1212? - RF CafeLong 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

Able Signal Amplified Digital Outdoor HDTV Antenna - RF CafeSince 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

Makerspaces & Maker Faires - RF CafeDIY (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

Challenges in Early Automotive Radio Design - RF CafeEarly 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

The Periodic Table of Substitute Performance - RF CafeIn 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 Concinnitas Project - RF CafeThe 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?

You've Heard of a Copyright, But How About a Copyleft? - RF CafeNo, 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

Tesseract Antique Instruments - RF Cafe SmorgasbordMy 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 "Fair Use" Doctrine and the U.S. Copyright Office - RF Cafe"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

Google Interview Questions - RF CafeQuestions 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

RF Cafe Now Has Google's 'Mobile-Friendly' Blessing - RF CafeMany 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"

GE Transportation in Erie, PA, Announces 950 Layoffs (Yogi Berra photo from Wikipedia)- RF CafeThat 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

FITSAT-1 CubeSat Flight over Erie, Pennsylvania - December 12, 2012 - RF CafeI 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...


Learn Almost Anything for Free

Khan Academy - "Learn almost anything for free" - RF Cafe"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*

RF Cafe Smorgasbord - Tax Day 2013: RF Cafe's *Fair Share* - RF CafeTax 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 [2012] federal [adjusted gross] income tax rate is 18.4%..."


PartSim Online Analog Circuit Simulator

PartSim Online Circuit Analysis Simulator by Aspen Labs - RF CafeSimulation 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...


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

RF Cafe Communications Central - RF CafeHow 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

Drawing a Circle with a Framing Square and 2 Nails - RF Cafe Smorgasbord"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

Foundational Questions Institute: Is the WOrld Analog or Digital? - RF CafeEach 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?

What's Fair About an Internet Sales Tax? - RF CafeYou 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?

Cost of Commuting Infographic (Streamline Refinance) - RF CafeHow 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

"I Didn't Know Ham Radio People Were Still Around" - RF CafeEvery week 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...


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