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Homepage Archive April 2014

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 Google Search box in the upper left corner of every page
Homepage Archive Pages
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13
2013:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2014:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec


Here is page 1 of the April 2014 homepage archive










The Transistom

The Transistom, April 1958 Radio-Electronics - RF CafeOoooh, I should have posted this story about 23 days ago, but better late than never. I meant to, but forgot. The story documents development of the "transistom" device back in the 1958 timeframe. Keep in mind that it was just a decade earlier that Mssrs. Bardeen, Brattain, and Shockley introduced the transistor amplifier to the world. The transistom was basically a 3-terminal transistor with two additional leads for a revolutionary power source built from radioisotopes of magnesium and manganese. In the day, school kids, including me, were handed blobs of liquid mercury to inspect and pass around in class, demonstrating how relatively ignorant we were about things we now consider to be extreme health hazards. Accordingly, encapsulating radioactive material in consumer devices... 

RF Safe-Stop™ - Unintended
GM-Like Consequences?

RF Safe-Stop™ by e2v (GM ignition switch type results?) - RF CafeSurvivalists have been encouraging people to buy vehicles that were manufactured prior to the time when electronic ignition systems and/or computer controls were added so that when "The Big One" hits, the EMP from a nuclear blast will not shut down their vehicles. In doing so, if you live through the event, you will at least still have serviceable transportation. Getting gasoline from a pumping station will be impossible since those computers will be dead, but there will be a lot of disabled vehicles sitting around with tanks full of gas for sale. Capitalizing on the vulnerability of modern cars and trucks - and even boats, motorcycles, and snowmobiles for that matter - to being stopped cold by a powerful electromagnetic field, military and law enforcement agencies are developing systems that simulate the results of a nuclear EMP event...

A New Tool for the Serviceman

A New Tool for the Serviceman - the VTVM, March 1930 Radio News - RF CafeYou are taught early in your electronics career to be mindful of the tendency for measurement equipment to affect the circuit it is measuring, and therefore the indicated results. In the case of high frequency circuits, even minute amounts of capacitance and/or inductance can render results utterly unusable, but even in circuits operating down to D.C. the simple internal resistance of a meter can profoundly affect measurement accuracy. High impedance circuits are particularly vulnerable to such "loading" effects by test equipment. For example, consider a circuit being measured that has an impedance of 10 kΩ and the internal resistance of the VOM is 100 kΩ. If the open circuit "true" voltage level is 11 V, then voltage division effected by the 100 kΩ meter in series...

The Day CRUD Radio Died

The Day CRUD Radio Died - RF CafeRF Cafe visitor and Amateur Extra Lynn L. sent me a link to this article titled "The Day CRUD Radio Died," by Donald Kimberlin. Mr. Kimberlin tells a real-life tale of an effort to track down and shut down a pirate broadcast station in southern Florida. The perpetrator, as it turns out, was an overambitious teenager who decided to provide a bit of listening enjoyment for his friends and anyone else within radio range. The hero of the story is a good-natured FCC marshal who, in spite of having to fight with his agency's bureaucracy, managed to 'convince' the lad to abandon his post. You will enjoy this quick read. It is posted on the Broadcaster's Desktop Reference website.

Tesslor R-601S Vacuum Tube
AM/FM Radio w/BT 3.0 Mod

Tesslor R-601S Retro Vacuum Tube AM/FM Radio w/Bluetooth 3.0 Modification - RF CafeFor all the time I invest in researching and writing about vintage radios of the vacuum tube variety, it is somewhat embarrassing to admit that I still do not have an operational set, although a Crosley 03CB console model is in the works now. I did, however, buy a Tesslor model R-601S AM/FM radio a couple years ago in order to be able to enjoy the warm orange glow of vacuum tubes while other projects were in the works. The R-601S is a nice mix of the old and the new in that while it uses vacuum tubes for the speaker preamp and output driver circuits, there is a state-of-the-art solid state receiver front-end and tuner. I did a write-up and video tour of the Tesslor R-601S radio in 2012. Last Fall (2013), Tesslor added Bluetooth 3.0 wireless connectivity capability to the R-601S and offered to update my radio...

Featured Productbr>ESD Work Station

Eclipse 900-056 Field Service ESD Protection Kit - RF Cafe Featured ProductHere is an item than can be worth it's weight in gold. At today's gold spot price of $1283/oz., this 12.8-ounce Eclipse 900-056 Field Service ESD Protection Kit would be worth $16,422. OK, maybe that's overstated, but depending on what type of equipment you happen to be working on, zapping an electronic component because you failed to exercise proper ESD protection measures could potentially (pun intended) cost that much. Silver closed at $19.39/oz., so maybe it is a bit more realistic as it makes this ESD work station worth $248. That's about the price of a replacement smartphone or midrange radio if you zap it while tinkering. Seriously, though, if you work on microelectronics without adequate ESD protection measures, you're asking for trouble. Even if you don't fry anything right away, you are likely to create the "walking wounded" scenario where failure is imminent in the future. $34 for this ESD work mat is cheap insurance.

RC Circuit Quiz

RC Circuit Quiz, June 1963 Popular Electronics - RF CafeHaving worked around resistors and capacitors for more than four decades comes in handy when presented with 'simple' quizzes like this one that appeared in a 1963 Popular Electronics dealing with RC circuits. Still, there is always some trepidation involved when being subject, even voluntarily, to a test of any sort, regardless of whether you are fairly confident that it will be a lead pipe cinch, a cake walk, child's play, so to speak. Even if nobody else will bear witness to your effort, you would feel like a real moron if you missed even one of those simple questions that anyone with your level of experience should get right without even having to think about it. Such is the irrational fear I have when taking these quizzes prior to posting them on RF Cafe. I have always been honest about the results...

Please Thank DongJin
Technology for Their Support

Dongjin Technology InnovationAs a premier manufacturer of RF connectors, cable assemblies and RF components, including specialty non-magnetic connectors, Dongjin TI is highly recognized an RF DongJin Technology Innovation Productsindustry leader in Korea. Our premium products offer a competitive price, on-time delivery and best quality in the industry. They have no minimum order size and 1-day delivery. Products are ISO9001, ISO14001, ROHS qualified, as required. VSWR reports are available on request.

Free Engineering Magazine

Free Engineering Magazine Subscriptions - RF CafeWouldn't it be nice if you could get a free subscription to your favorite hunting, bicycling, or cooking magazine merely by demonstrating that you have a vested interest in the subject that advertisers can exploit? Don't be looking for a year's worth of Field & Stream, Road Bike, or Baking to arrive in your mailbox anytime soon, but you can, if you are qualified, received complimentary subscriptions to many of the big-time engineering magazines. Here are just a few of scores available.

Advantages of Outdoor

Advantages of Outdoor Antennas, June July 1940 National Radio NewsBoth funny and ridiculous I thought as I read this article from a 1940 edition of National Radio News where author Julius Aceves, a consulting radio engineer, makes the case for not buying a newfangled, cheap radio that is supplied with a built-in antenna when using a good old-fashioned outdoor antenna is the better option. It's not that he doesn't have a valid point about the larger, obstruction-free outdoor antenna providing superior signal strength and a greater signal-to-noise ratio; it's that part of his argument is that in doing so you are denying the outdoor radio antenna companies revenue. That mindset is akin to telling people they should not buy notebook computers because...

MECA Electronics Ad
for the MTT-S Show (IMS2014)

MECA Electronics Ad for the MTT-S Show (IMS2014) - RF CafeMECA Electronics would appreciate your taking a few moments to take a look at their newest magazine advertisement that highlights products they will feature at IMS2014 in Booth #842.

Career News & Job Hunting

Career News & Job Hunting (April 21, 2014) - RF CafeIt's been a couple weeks since posting links to stories on job searching and career management. I should put an entry on my weekly calendar to do so. The stock market is way up so the economy - and therefore the job market, must be going smashingly well - right?

 • IEEE ResumeLab
 • Don't Give It All Away at
    the Job Interview
 • 4 Ways to Make the Most
    of a Business Opportunity
 • 3 Steps to Take If You Are
    Rejected from Your Dream
 • Newest Organized Labor
    Group: Start-up Employees
 • DiscoverE[ngineering].org

Notable Tech Quote

President Kennedy's address to the Irish Parliament in June 1963 - RF Cafe Notable Quote"The problems of the world cannot possibly be solved by skeptics or cynics, whose horizons are limited by the obvious realities. We need men who can dream of things that never were, and ask why not." - President Kennedy's address to the Irish Parliament in June 1963, JFK Presidential Library

MegaRF Design Services

MegaRF Design: "Making Technology Happen Today" - RF CafeMegaRF Design, of Escondido, CA, is a relatively new startup engineering design and development service. Owner Steve Massey, with his many years of circuit and system experience, is currently consulting with major RF and microwave companies to provide engineering design services to develop products for the commercial communications and military marketplace. All levels of service are provided. He will work with you from conception to schematics to layout to physical products, and everything in-between. RF testing and PCB prototyping services are available to complement the consultant design services (see extensive list of in-house equipment and software). Please call Steve at 760-748-MEGA (6342) to learn more. "Let's go get it done!"

Wireless Crossword Puzzle
for April 20, 2014

Wireless Crossword Puzzle for April 20, 2014 - RF CafeI considered not bothering to create these custom engineering themed crossword puzzles anymore, but in checking the website statistics, I discovered that my collection of crosswords that began more than a decade ago has generated more than 58,000 page views just in the last year alone. Evidently there are people who are interested. Since I make each one new every week, it is easy for me to create a custom puzzle for your company, school, club, event, etc. Send me an email if you have a request.

MPN-13 GCA Radar Model by
USAF Tech Elbert Cook

MPN-13 GCA Radar Model by Elbert Cook - RF CafeElbert submitted photos of his completed MPN-13 GCA model with a spiffy real-looking camouflage paint job! It includes both the maintenance trailer and the operations trailer, complete with ASR antenna, PAR antennas (az/el), VHF and UHF antennas, and navigation hazard lights. The "M" part of "MPN" stands for "mobile." As such, I and hundreds - maybe thousands - of USAF radar technicians have over the decades disassembled, transported, and reassembled these radars many times. My radar shop at Robins AFB, GA, participated in what were code-named "Healthy Strikes" two or three times each year, whereby a claxon in the barracks rudely awoke 5th Combat Communications Group members at around 5:00 am to signify the beginning of what would be about a week...

Walter Drake Releases Guide
to Thermoformed Packaging

Walter Drake Releases Guide to Thermoformed Packaging - RF CafeWalter Drake, a thermoformed packaging manufacturer, has recently released the "Purchasers Guide to Thermoformed Packaging". The guide will assist buyers and Purchaser’s Guide to Custom Thermoformed Packagingspecifiers in the correct selection of thermoformed packaging such as plastic clamshells, thermoformed trays and blister packs. Walter Drake designs and manufactures custom thermoformed plastic packaging in the form of clamshells, trays and blisters for the medical, pharmaceutical, electronic (ESD, static dissipative), consumer and industrial packaging applications.

Do You Need an Expert
to Sue an Expert?

Do You Need an Expert to Sue an Expert?, by IMS ExpertServices - RF CafeThis article by Bob Ambrogi, of IMS Expert Services, rhetorically asks the question of whether an 'expert' is required in order to sue another 'expert' because of his sworn testimony. Bob Ambrogi, IMS ExpertServicesIn this particular case an expert was hired to help prove claims of wrongdoing by a neighboring industrial complex. Being declared qualified as an 'expert' varies from state to state, but it usually requires extensive documented professional experience, and/or an advanced college degree, and/or professional registration as a result of special testing. I, for example, would likely not qualify to serve as an expert witness in a trial. Like it or not - and many people believe it to be a form of acceptable payola...

ECM Announces Distribution
Agreement w/MECA Electronics

ECM - East Coast Microwave Distributors, Inc. Announces New Authorized Distribution Agreement with MECA Electronics, Inc. - RF CafeECM announced a new authorized distribution agreement with MECA Electronics to supply the manufacturer's line of USA made rugged & reliable RF/microwave passive DC – 20 GHz microwave components and solutions globally.MECA Electronics MECA serves all areas of the RF/Microwave industries including world class network providers. They have long been the "backbone" of high performance wired and air-interfaced networks such as in-building applications, satellite communications, radar, radio communications, telemetry applications, mobile radio, aviation and air traffic communications...

Carl & Jerry: Aiding an Instinct

Carl & Jerry: Aiding an Instinct, December 1962 Popular Electronics - RF CafeBy 1962, John T. Frye's techie troubleshooting teenagers Carl and Jerry had graduated from high school and were attending Parvoo University (PU?) as electrical engineering students. It was a natural progression. Unlike many of the company names and products - like the Delco DN278 transistor mentioned here - that appeared in the Popular Science series, the college's name is fictional. Maybe author Frye had a connection to Porvoo, Finland, and Anglicized the name. I ran "parvoo" through a couple online anagram solvers to see if it was a disguised name (which would be apropos for a detective story) and the closest it came to a real word is 'vaporo,' which is an Esperanto term...

Don't Quit!

Don't Quit!, December 1940 January 1941 National Radio News - RF CafeWhen I first saw the title of this poem from a 1941 edition of National Radio News, I thought it was going to be a plea to amateur radio operators not to give up their hobby just because the government would eventually prohibit broadcasting during the World War II years. As it turns out, the poem predated that era and is instead a generic encouragement to the magazine's readers to press on regardless of obstacles. It did show up in the Christmas issue, so maybe it was simply a message in the spirit of peace on Earth and goodwill toward man. In these harsh years of the government fomenting division and class envy amongst its citizens, it's kind of hard to relate to such a gentle, kindly mindset, but indeed it did once exist in America. Anyway, I though it was worth reprinting here. "Don't Quit" is sort of a simpler version of Rudyard Kipling's famous poem of inspiration titled "If."

123D Circuits
for Arduino Development

123D Circuits for Arduino Development - RF CafeIf you haven't yet heard about the Arduino single board computer (SBC) experimenter's platform, then either you have been in a coma or you are just now entering the tech world. Think of Arduino as the electronic version of the famous mechanical Erector Set that was popular beginning in the early 20th century. Or, consider it the "grown-up" version of Lego's computerized Mindstorms building sets. Per the official website, "Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for artists, designers, hobbyists and anyone interested in creating interactive objects or environments...

!!! FREE SMA Finger Wrench !!!
Courtesy Bracke Mfg.

SMA Finger Wrench Available from Bracke Manufacturing - RF CafeWe now have a source for those much-sought-after plastic SMA finger wrenches! Bracke Mfg manager Lawrence P. sent me an email today saying that Bracke will be glad to mail anyone who requests them a sample of up to 5 of the SMA finger wrenches - what a guy! I'm guessing he saw the plea posted here on RF Cafe and on various forums for people looking desperately for the things. The SMA finger (thumb) wrench, known also by its Latin binomial nomenclature of 'digitus divellit,' is a rare breed of tool for the RF / microwave engineer, and appears to be indigenous to industry trade shows like MTT-S and European Microwave Conference...

Space Electronics:
Satellites and ET EM Waves

Space Electronics: Satellites and ET EM Waves, May 1961 Popular Electronics - RF CafePrior to around 1960, the nature of electromagnetic radiation outside the Earth's atmosphere was entirely a matter of scientific conjecture. As is evidenced by this 1961 article, at the time it was still not known for certain whether electromagnetic energy outside the bands transmitted through the ionosphere existed for sure. There was of course no reason to believe that low frequency, long wavelength radio waves were not present along with the rest of the spectrum, but experiments needed to be developed that would launch satellites above the atmosphere to detect probable out-of-band signals and then re-transmit them on frequencies known to easily penetrate the 'ether.' Many failures occurred along the way, but persistence paid off...

After Class:
Explaining Tuned Circuits

After Class: Explaining Tuned Circuits, May 1961 Popular Electronics - RF CafeFundamentals of resonant tank circuits has not changed since they were first investigated more than a century ago. This "After Class" tutorial that ran in the May 1961 edition of Popular Electronics is typical of the series where the author speaks as though he was giving an impromptu lesson to a gathering of students after the scheduled classroom period was over or, in this instance as though he was having a casual discussion with a friend who was perplexed by a particular electronics phenomenon. Figures and equations are often drawn by hand to augment the informal setting rather than being typeset. Here, "Larry" is amazed... 


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