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Homepage Archive January 2015- page 1

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. About RF Cafe.

Homepage Archive Pages

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Here is page 2 of the January 2015 homepage archive.

Editorial: Radio Dumping

Radio Dumping, February 1939 Radio-Craft - RF Cafe

"The situation is one that is difficult, if not wholly impossible to eradicate, because of all modern, 20th Century machine age products, the radio receiver of today undergoes more violent and more radical changes than almost any other single item we can think of." That was the lament of electronics inventor, publisher, and industry visionary Hugo Gernsback in 1939! He wrote of the practice of electronics component manufacturers vastly overproducing products and then, when they are quickly obsoleted due to newer better ones entering the market space, selling at below cost in hopes of recovering at least some of their investment. For man who otherwise encouraged, welcomed, and participated in the pushing forward of technological frontiers, the attitude seem strangely at ...

iPhone 6 Plus vs. Samsung

Galaxy Note 3 - "Will It Blend?"

iPhone 6 Plus & Samsung Galaxy Note 3 - "Will It Blend?" - RF Cafe Video for EngineersThere is no denying Blendtec founder Tom Dickson has earned the title of überBlendermeister with his online "Will It Blend?" series of videos. Using his company's Total Blender, Tom has over the years inserted, among many other things, popular and often expensive high-tech devices, and then pressed the appropriate button on the machine to start the action. Since its beginning in 2007, "Will It Blend?" videos have documented in a combination of full speed and slow motion the pulverizing of iPhones, iPads, Galaxy phones, Windows phones, Kindles, laser pointers, wii remote controls, Xbox 360 Kinect, a hearing aid, a video camera, magnets, and even a cassette tape. In the most recent episode, Tom hosts a ...

How Radio Waves

Are Propagated

How Radio Waves Are Propagated, October 1935 Short Wave Craft - RF CafeIf you or someone you know is just starting in the realm of radio and want a really nice pictorial presentation of the basics of radio wave propagation, then this one-page article from a 1935 edition of Short Wave Craft is just what you need. Phormula phobia (aka formula fobia) will not be an issue for anyone. The fundamentals have not changed in the intervening 80 years.

Amelia Earhart's Short-Wave

Radio Never Failed

Amelia Earhart's Short-Wave Radio Never Failed, April 1935 Short Wave Craft - RF CafePlenty of intrigue still surrounds the July 2, 1937, disappearance of Amelia Earhart in the South Pacific on her way to completing an around-the-world flight. This article appeared two years prior to that fateful flight proclaiming the soundness of her onboard radio. Back in the day, shortwave radio installations in aircraft required long wires trailing behind, particularly for long distance requirements like flying from the U.S. mainland to Hawaii. Those wires were a constant source of trouble due to destructive mechanical oscillations while waving in the airstream, airframe damage due to striking during the haul in/out procedure, and breakage. According to an article that appeared in the January 2015 edition of Smithsonian magazine, it is suspected ...

How to Bend Your Own Chassis

How to Bend Your Own Chassis, April 1935 Short Wave Craft - RF CafeDespite all the prefabricated, relatively inexpensive products available these days, there are still many people who like to build their own projects. Whether electrical or mechanical - or both - some sort of enclosure is usually involved. Often, you can cannibalize an existing, retired project to use its chassis or find a product at Walmart or a home improvement store that does not cost too much that you can buy just to get its enclosure. Buying a pre-formed chassis for your project can get expensive, so there are times when the best option is to obtain a piece of sheet metal (which can also be expensive) and bend it yourself. If you have never attempted such an endeavor, believe me it can be pretty challenging, especially with heavier gauge ...

RFMW Announces Wideband GaN

Driver Amplifier from Qorvo

RFMW-Wideband-GaN-Driver-Amplifier-Qorvo-1-13-2015.htm" > RFMW Announces Wideband GaN Driver Amplifier from Qorvo - RF CcafeRFMW, Ltd. announces design and sales support for a 2-6 GHz RFMW-Wideband-GaN-Driver-Amplifier-Qorvo-1-13-2015.htm" >GaN driver amplifier from Qorvo, the new company name for the merger of TriQuint and RFMD. The RFMW-Wideband-GaN-Driver-Amplifier-Qorvo-1-13-2015.htm" >TGA2597 provides a saturated output power of 31.5 dBm with >31% PAE. Small signal gain of the TGA2597 is greater than 24 dB with large signal gain >13.5 dB. Qorvo offers the TGA2597 for radar, EW and communication applications requiring low current (40 mA) from a 25 V supply. Offered as die, a packaged version is available RFMW-Wideband-GaN-Driver-Amplifier-Qorvo-1-13-2015.htm" >...

Look, It's 'Apple Man!'

Look, It's iPhone Man! - RF CafeChina mocked a hapless 'iPhone armour' smuggler. "Customs officials suspicious of a man's 'weird posture' made a startling discovery when they searched a man attempting to leave Hong Kong: a suit of armour made of 94 iPhones and several rolls of cling film." The poor guy must not have been very bright if he didn't think anyone would notice. Even if he managed to pass visual inspection, the x-ray machine would have nailed him.

Advanced Test Equipment Corp.

Looking for SQL Report Writer

Advanced Test Equipment Corporation Looking for SQL Report Writer, January 6, 2015 - RF CafeAdvanced Test Equipment Corp. is a nationwide test & measurement equipment company and for more than 33 years, we demonstrate our commitment to providing quality equipment support by meeting our customer's needs. We are currently looking for an SQL Report Writer to assist the IT department with installation, configuring, monitoring, troubleshooting servers, applications network infrastructure and assist in the integration of our in house GP and CRM software programs. Duties will include validating report data, converting Crystal ...

Tax Court Okays Use of Predictive

Coding to Review Documents

Tax Court Okays Use of Predictive Coding to Review Documents, by IMS ExpertServices - RF CafeThis article by Joshua Fruchter, writing for IMS ExpertServices, expands on the subject of predictive coding as submissible evidence on court proceedings that began with an article written in 2006 by Maggie Tamburro, The Future of Predictive Coding - Rise of the Evidentiary Expert? Ms. Tamburro noted, "At the heart of predictive coding lies the concept of 'supervised learning,' defined as 'an algorithm that learns from human decisions and then has the ability to apply those decisions to new data.'" It seems from reading both stories that the courts are not allowing results from predictive coding to be used as conclusive evidence of wrong-doing, but merely as a tool during the discovery process to uncover potential wrongdoing, and then to investigate farther. While that seems innocent enough, I equate it somewhat with the claim that if you have nothing ...

Notable Tech Quote

for January 13, 2015

Kevin Nolan, VP of GE Home & Business Solutions, in January 2015 Popular Science - RF Cafe"We think the new IP is speed. People who can move fast are going to win." - Kevin Nolan, VP of GE Home & Business Solutions, in January 2015 Popular Science, "Make, Inc."


CQ CQ CQ KB3UON/AG - RF CafeWell, I finally got around to taking the test for my Amateur Radio license to advance to the General Class! It is somewhat embarrassing to admit that I bought the study material nearly 3 years ago, but a lot of things kept bumping priority to a lower level. My Technician Class license was earned on May 24, 2010, so nearly 5 years have passed. There is no statute of limitations for how long you have to advance to the next level, although licenses are issued for 10-year terms. The impetus at this point was that the question pool is due to change again in July of 2015, so I wanted to make sure to git 'er done before then; otherwise, it would require becoming familiar with the new material. The ARRL is responsible for administering the test on behalf of the FCC. My local Ham radio club administers exams an hour ...

UMTS Link Planning Spreadsheet

UMTS Transmission Link Planning Tool for Excel - RF CafeMr. Alok K. Tiwari, of Idea Cellular Ltd., has graciously made this UMTS Transmission Link Planning workbook available. Says Mr. Tiwari, "I have formulated Link Budget calculation in Excel spreadsheet for WDCMA. The spreadsheet uses comprehensive detail of RF fundamentals and formulas to decide cell radius, numbers of cell sites, and different types of clutter. The spreadsheet has been designed to help new engineers to understand the WCDMA RF concept in more details." As with his Transmission Link Planning Tool, this spreadsheet provides a very large number of essential calculations for planning purposes based on user-provided parameters. Examples include receiver thermal noise density, noise figure, noise power, interference margin, processing gain, sensitivity, and path loss. Cell radius, range, ...

$5.00 for Best Short Wave Kink

$5.00 For Best Short Wave Kink, October 1935 Short Wave Craft - RF CafeIf MacGyver had been around in 1935, every episode would have included a Fahnestock Clip as part of a scheme to get Angus (his first name - no kidding) out of perilous situations. The handy little devices were very popular in electronics, both for hobbyists and for commercial products, until fairly recently (within the last two decades) because they provide a simple, reliable electrical connection that does not require any tools for use - other than your finger. If you have never heard of a Fahnestock clip, you will probably be surprised to learn what one is and chances are you have seen one and maybe even used one. If you work in an electronics prototyping lab area that has been around for ...

Link Planning Tool v7a

Minor Update

Transmission Link Planning Tool for Excel - RF CafeMr. Alok Tiwari, of Idea Cellular Ltd., Delhi, India, has provided a minor update to his very nice (and free) Link Planning Tool spreadsheet. Says Mr. Tiwari, "Based on users feedback regarding some of the buttons not working properly, I have just gone through the sheet to make those necessary corrections in the macro used. Almost no change has been made in formulas." This is a very extensive calculator. As supplied, the spreadsheet is locked to prevent accidental overwriting of formula cells. You are invited to e-mail him for the passwords. Also, Mr. Tiwari sent a new spreadsheet titled Link Budget UMTS, which I will be posting soon.

An Introduction to Television

$4M for 30s Super Bowl XLIX Spot

An Introduction to Television, $4 Million for 30-Second Super Bowl XLIX Spot - RF Cafe

Companies will pay $4 million for a 30-second spot for Super Bowl XLIX this year. "We are standing on the threshold of the Age of Television!" "Television will enliven and broaden your life more than you can now appreciate. It will become part of your daily life just as radio is today." "The best evidence that the public thinks well of television is the universal response that comes from those who have a chance to see it." Broadcast television which will add a new dimension to home entertainment and will provide one of the most powerful mass advertising media ever developed." So proclaimed spokesmen for Dumont, Farnsworth, Philco, and General Electric, respectively, in 1945. GE clearly had its future pegged on the real revenue potential ...

Radio & Radar Crossword

Puzzle for January 11, 2015

Radio & Radar Crossword Puzzle for January 11, 2015 - RF CafeThis weeks Radio and Radar Engineering Crossword Puzzle uses words and clues that come from my hand-selected file of items that pertain exclusively to science and engineering. Enjoy.

Wells-Gardner Series 062

Automotive Superhet Radio

Wells-Gardner Series 062 Automotive Superheterodyne, October 1932 Radio Craft - RF CafeI did not see anything particularly stand-out-ish about the Wells-Gardner Series 062 automotive superheterodyne radio. The 'eliminator' option of the 'eliminator or battery' label presumably refers to an AC-to-DC power supply that can be used either during maintenance or if the listener chooses to employ the radio in use outside of a vehicle - or else has a very long extension cord ;-) As with all these radio data service pages, this one is posted for the benefit of both researchers and for restoration types who need ...

Galvin Motorola Model 61

Automotive Receiver

Galvin Motorola Model 61 Automotive Receiver, October 1932 Radio Craft - RF CafeWhat the heck is an Elkonode? That was my response to its mention in this Radio Service Data Sheet for the Galvin Motorola Model 61 Automotive Receiver. A Google search turned up a datasheet on the Mallory Elkonode. Per the info, "The series 60, 70, and 80 Mallory Elkonodes are described as single-reed, full-wave inverters, with self-contained synchronous rectifiers. These units within themselves supply direct current, high voltage for radio receiver plate supply. No tube rectifiers as required with these types." This 1932 vintage article recommends against attempting self-repair of Elkonodes, so restoration ...

Electro Sonic Supply Co. Ltd.

C.O.D. Invoice from 1958

Electro Sonic Supply Co. Ltd. C.O.D. Invoice from 1958 - RF CafeAlthough it is not my motivation for buying vintage electronics magazines, I do keep hoping that some day I will turn a page and find tucked inside an initial issue preferred stock certificate of a company like Westinghouse Electric, Lockheed Aircraft Corporation, American De Forest Wireless Telegraph Company, or any other similar company. Alas, thus far it has not happened. However, I have found interesting inscriptions from previous magazine owners who evidently planned to build one of the circuits presented in an article, as well as an occasional item like this C.O.D. (collect on delivery) invoice from the Electro Sonic Supply Co. Ltd. (c.1958). ESSCO, as ...

Career and Job Hunting Advice

for January 9, 2015

Career and Job Hunting Advice for January 9, 2015 - RF CafeIf one of your New Year's resolutions was to find a new company to work for, start your own company, or just improve your situation with your current employer, then this is the time to begin. As always, there are plenty of 'experts' out there ready and willing (but not always qualified) to offer assistance. You have to see the cartoon on the "Finally! This is Exactly How You Research a Potential Employer" page ...

- Annoying Coworkers

   Infographic - Are You Guilty of

   One of These Deadly Office


- CareerBliss 50 Happiest

   Companies in America for


- How to Make the "Greatest

   Weakness" Question a

   Strength  <more>

Empower RF Systems Introsbr>80-1000 MHz, 500 W PA

Empower-RF-Systems-80-1000-MHz-500-W-PA-1-7-2015.htm" > Empower RF Systems Intros 80-1000 MHz, 500 W Power Amplifier - RF CafeEmpower is pleased to be releasing additional, industry leading power amplifier models that compliment the frequency coverage and power level "footprint" of our next generation, high power PA product family. Model 2175, covering 80 to 1000 MHz and delivering 500 W of broadband output power in a 3U, air cooled chassis is market released and available for immediate purchase. Offering unrivaled size / power advantages and building on a design architecture that has been a catalyst for technology upgrades from customers with diverse requirements from multiple Empower-RF-Systems-80-1000-MHz-500-W-PA-1-7-2015.htm" >...

Antenna & Site Design Seminars

Delcross Technologies Antenna & Site Design Seminars - RF CafeDelcross Technologies is offering free seminars on antenna and site design based on its software product offerings. This appeared on LinkedIn today, but since not every RF Cafe visitor gets the memo, I figure it's worth presenting here.

- RF Cosite EMI Analysis and

   Mitigation for an Unmanned

   Aerial System (UAS), Jan. 14

- Using Ray Visualization in

   Savant as a Diagnostic Tool

   for Installed Antenna

   Performance and Reflector

   Design, Jan 28

- Preparing CAD models for

   Installed Antenna

   Performance Simulations in

   Savant, Feb. 11

- Antenna Models in Savant -

   Feb 25

Epiq Solutions Looking for a

Senior RF Hardware Engineer

Epiq Solutions Looking for a Senior RF Hardware Engineer - RF CafeEpiq Solutions is seeking a full-time Senior Hardware Engineer with at least 5 years of experience to join our team developing both custom and commercial wireless communications systems. The ideal candidate would have a passion for developing board-level analog and RF hardware designs, along with previous experience developing digital hardware designs. The candidate should have experience with the entire hardware design cycle, from concept to production. Specific job tasks include the following: Develop block diagrams of potential hardware design concepts from high level requirements, rapid prototyping and/or simulation of hardware ...

Avoiding Redesign: The

Importance of Upfront Planning

Orbel-Avoiding-Redesign-Importance-Upfront-Planning-1-5-2015.htm" > Orbel: Avoiding Redsign: The Importance of Upfront Planning - RF CafeOrbel has published a white paper on planning Orbel-Avoiding-Redesign-Importance-Upfront-Planning-1-5-2015.htm" >photo-etched components. "I wish we had thought about that when we started our design effort." Because of outside stresses—delivery dates, quality expectations, and budgetary limitations—a metal component being developed to prove a concept is often not ready for a high-speed stamping press. If the end goal is not addressed early, a redesign is looming in the future. What should an engineer responsible for a project be thinking in order to avoid delays and cost escalations? Photo-etching is Orbel-Avoiding-Redesign-Importance-Upfront-Planning-1-5-2015.htm" >...

End-Fed Zepp Antenna

for Receiving

End-Fed Zepp for Receiving, November/ December 1941 Radio Craft - RF CafeAny mention of a 'Zeppelin' conjures up thoughts of disaster in the form of the famous Hindenburg incident at Lakehurst, New Jersey, back in 1937. Fortunately, not all things 'Zepp' are bad news. The end-fed Zepp (short for Zeppelin) antenna is as popular today as it was when the Germans developed it for use in the Zeppelin airships. One of the major advantages to an end-fed Zepp is that it is, as the name suggests, fed from the end rather than in the center like a dipole. The configuration makes installation simpler than a dipole. Being so simple in construction, the Zepp handily functions as a multi-band harmonic antenna so it is useful on, for instance, the 160, 80, 40, 20, and 10 meter Ham bands. Many companies ...

M/A-COM Intros Broad Portfolio

of DOCSIS 3.1 Compliant Passives

MACOM-DOCSIS-3p1-Compliant-Passive-Components-1-6-2015.htm" > MACOM Introduces the Industry's Broadest Portfolio of DOCSIS 3.1 Compliant Passive Components - RF CafeM/A-COM Technology Solutions, a leading supplier of high-performance RF, microwave, millimeterwave and photonic products, today announced a comprehensive new portfolio of passive components for MACOM-DOCSIS-3p1-Compliant-Passive-Components-1-6-2015.htm" >DOCSIS 3.1 compliant cable TV (CATV) and broadband Internet systems. This new product family, spanning upstream and downstream transformers / baluns, couplers and power dividers/combiners, is the industry's broadest portfolio of passives specifically designed to comply with the DOCSIS 3.1 standard for high-bandwidth MACOM-DOCSIS-3p1-Compliant-Passive-Components-1-6-2015.htm" >...

Congrats to Justin W. for Being

the December 2014 Book Winner!

Troubleshooting and Repairing Commercial Electrical Equipment - RF CafeJustin W., of Vero Beach, Florida, is the drawing winner for December 2014. Justin wisely selected Troubleshooting and Repairing Commercial Electrical Equipment, by author David Herres. Mr. Herres personally provided the book to me as a gift for writing a review of his earlier book titled 2011 NEC Chapter-by-Chapter. Each month I randomly select one or two people from a list of purchasers of my software to receive a free book, and I even pay the postage costs. The value of the book typically far exceeds what is spent on software. Am I a nice guy or what? ;-)

Data Fraud or Incompetence?

Data Fraud or Incompetence? - RF CafeNever send a J-school graduate to do a mathematician's job. Most journalists are quick to admit - even boast of - their fear of and incompetence in math. Either because of it or in spite of it, they tend to rely heavily on statistical results published by other entities, which unfortunately are equally incompetent journalists. It is an incestuous relationship that can be found over and over again. Sometimes, though, writers armed with numbers and cool graphing software attempt their own versions of serious data analysis. Caveat emptor to anyone reading such an article. To wit: The following headline appeared in The New York Times, "How Nonemployed Americans Spend Their Weekdays: Men vs. Women." Looking to feed my sense of ...

RF & Microwave Engineering

Articles for January 7, 2015

RF & Microwave Engineering Articles for January 7, 2015 - RF CafeThis is my first batch of useful RF & microwave engineering articles for 2015 editions of the industry's premier engineering magazines. The selection, as always, reflects my personal preferences, but I do throw in a few that just plain look interesting. Hopefully, 2015 will be as replete with good articles as was 2014. 

- Microwaves & RF's Top

   Products of 2014 List,

   D. Brown & J.J. DeLisle

- Merger Movement in 2014,

   P. Hindle

- Quick & Dirty Impedance,

   Noise, and Jitter

   Measurements, G. Chenier

- View from the Top, R. Hawkins

- View from the Top,

   B. McCutcheon

- Microwave Week Makes a

   Splash in Tampa Bay,

   J.J. DeLisle   <more>

An Amazing Story

An Amazing Story - RF CafeLast night I received a call from my daughter, Sally, following an encounter she had with a deer standing in the road. The yearling buck was just standing in the road as if it had already met a taxidermist, not moving at all. Unlike me, who would never even consider approaching the beast, Sally, who owns and works with a dozen horses on her Equine Kingdom farm every day, got out of her car and went over to the deer. She cautiously reached out and petted it, and it remained motionless - not even a blink. It was in fact alive, but once she noticed the blood seeping from its nose and mouth, it was apparent that the poor thing had been hit by a ...

GaN Thermal Analysis for

High-Performance Systems

GaN Thermal Analysis for High-Performance Systems (Qorvo whitepaper) - RF CafeThis paper addresses TriQuint's (now Qorvo) integrated approach to thermal design that leverages modeling, empirical measurements (including micro-Raman thermography), and finite element analysis (FEA) for high performance microwave GaN HEMT devices and MMICs. This methodology is highly effective and has been empirically validated. By properly addressing FEA boundary condition assumptions and the limitations of infrared microscopy, resulting model calculations are more accurate at both the product and end application level than traditional methods based on lower ...

Advanced Test Equipment

Looking for a Repair Lab Tech

Advanced Test Equipment Corp. has in immediate need for a Repair Lab Technician to, among other duties, calibrate, troubleshoot Advanced Test Equipment Rentals Team Photoand repair a wide variety of equipment, including: RF, microwave, fiber optic, scopes, meters, and power supplies. Proficiency in solder / desolder rework required. 5 years minimum experience ...

Advanced Test Equipment

Needs a Calibration Technician

Advanced Test Equipment Corporation Needs a Calibration Technician January 6, 2015 - RF CafeAdvanced Test Equipment Corp is a nationwide company that focuses on the rental of a wide variety of equipment working in a fast paced environment. We are looking for and experienced Calibration Technician to calibrate, troubleshoot, and repair a wide variety of equipment, including but not limited to: analyzers, GPTE, fiber optic, scopes, meters, power supplies, and more.

Featured Book -The Scientists:

A History of Science

The Scientists: A History of Science Told Through the Lives of Its Greatest Inventors - RF CafeThe Scientists: A History of Science Told Through the Lives of Its Greatest Inventors, by John Gribbin. "A wonderfully readable account of scientific development over the past five hundred years, focusing on the lives and achievements of individual scientists, by the bestselling author of In Search of Schrödinger's Cat. In this ambitious new book, John Gribbin tells the stories of the people who have made science, and of the times in which they lived and worked. He begins with Copernicus, during the Renaissance, when science replaced mysticism as a means of explaining the workings of the world, and he continues through the centuries, creating an unbroken genealogy of not ...

The New Handy-Talkie

The New Handy-Talkie, December 1942 Radio Craft - RF CafeWhen my kids were young and we lived in a wooded area, I bought a set of Motorola Family Radio Service (FRS) radios for them to carry so that Melanie and I could keep track of them while they were outside playing. There was a little fishing pond a few hundred feet into the woods that they liked to visit (and occasionally catch a trout). The radios were palm-sized and had a range of about a mile and operated on a few AAA batteries. That represents a huge advance in technology compared to the first 'portable' hand-held radios that appeared on the battlefields during World War II - the Handy-Talkie. Handy-Talkies used vacuum ...

Audel's Radioman's Guide


Audel's Radioman's Guide Ad, September 1942, Radio Craft - RF CafeTheodore Audel, a pen name and company name (Audel Publishers) used by Nehemiah Hawkins, published many technical handbooks covering electronics, mechanics, electric motors, mill working, carpentry, machining, plumbing, masonry, automotive, steam fitting, physical plant engineering, power generation systems, hydraulics, home appliances, oil burners, sheet metal working, refrigeration, and even gardening. I have a 1945 edition of Audels Carpenters and Builders Guide #1 that came from my grandfather, who was a carpenter. It is chock full of useful information, and I suppose the Radiomans Guide is as well. The title page quote is, "By Hammer and Hand All ...

RFMW Announces New

European Sales Director

RFMW-Announces-New-European-Sales-Director-1-5-2015.htm" >RFMW Announces New European Sales Director - RF CafeRFMW, Ltd. announced that RFMW-Announces-New-European-Sales-Director-1-5-2015.htm" >Christian Grieswelle has been promoted to the position of Director of Sales for RFMW Europe. Mr. Grieswelle has served as RFMW's Germany Country Manager for the past 3 years. As such, he has established a successful track record of developing RFMW's presence in Germany. In recognition of Mr. Grieswelle's business development and keen managerial skills, he will be leading and further developing the European sales team who now report to him in their RFMW-Announces-New-European-Sales-Director-1-5-2015.htm" >...

Feedback Tone Control

Feedback Tone Control, December 1958 Radio-Electronics - RF CafeI have to admit to not being real certain why I selected this article on feedback tone control for posting. Although it is a good write-up on some simple audio frequency filtering circuits, and the principles can be applied to any frequency, it is most likely this page was marked because it contained an electronic-themed comic on it. Oh well, Melanie already scanned and OCRed it for me, so you might as well go ahead and read it.

Notable Tech Quote

.com vs. .whatever

Christine Lagorio-Chafkin and Chad Folkening (Inc. images) - RF Cafe"I see 98 percent of your sales last quarter were URLs that end in the traditional dot-com." - Christine Lagorio-Chafkin, Inc. magazine writer, interviewing $35M/year Domain Holdings co-founder Chad Folkening. I've always recommended to people that they buy a '.com' domain name for a business because even with the hundreds of '.whatevers' available now, nearly everyone assumes you have a '.com.'

New Letter Writing Contest

for Servicemen

New Letter Contest for Servicemen - Hallicrafters, August 1944, Radio Craft - RF CafeHallicrafters was a premier manufacturer of radios for commercial, hobby, and military use before World War II broke out. Once the United States was drawn in by the Imperial Japanese Navy's December 7, 1941 surprise attack on Pearl Harbor, no time was wasted converting the majority of production for electronics, transportation, and other realms into almost exclusively war production. Hallicrafters was, of course, onboard. Life took a sudden turn for many Americans as fathers, husbands, cousins, uncles, and brothers went off to fight battles in foreign lands. Communications to and from loved ones back home were difficult as priority was assigned to military ...

Anatech's January 5, 205

Product Update

anatech-product-update-1-5-2015.htm" > Anatech Electronics Product Update January 5, 2015 - RF CafeAnatech Electronics offers the industry's largest portfolio of high-performance standard and customized anatech-product-update-1-5-2015.htm" >RF and microwave filters and filter-related products for military, commercial, aerospace and defense, and industrial applications up to 40 GHz. Anatech has released three new bandpass filter designs: A 480 MHz helical BPF, a 100 MHz LC BPF, and a 10.5 kHz crystal BPF. All can be ordered directly through their AMCrf web store.

Parallel Resistance Chart

... & Capacitance & Inductance

Parallel Resistance Chart, October 1958 Radio-Electronics - RF CafeIf you have ever placed a fixed resistor in parallel with a potentiometer to reduce the total resistance, then you are familiar with how you also convert a linear relationship of the wiper movement with resistance to one that is nonlinear. That is because the equation changes from Rtotal = xRpotentiometer (where x is the potentiometer position) to Rtotal = (xRpotentiometer • Rparallel) / (xRpotentiometer + Rparallel). The graph of it looks like one of the curves in this chart. Since the total parallel resistance is always smaller than the lowest value of the two resistances, the greater the ratio of the two is, the more dominant the smaller resistance value becomes. That means as the potentiometer ...


Microwave Engineering

Crossword Puzzle

Microwave Engineering Crossword Puzzle for January 4, 2015 - RF CafeThis is 2015's first Microwave Engineering Crossword Puzzle. As with all my other custom generated crosswords, you will find only engineering and science related words and clues. Enjoy, and have a Happy New Year!

Electronics on the Hurricane Ship

Electronics on the Hurricane Ship, October 1957 Radio & TV News - RF CafeIf you enjoy reading about instruments with names like the Eppley pyrheliometer and the conductivity bridge salinometer, then this article is for you. Long before there were Earth-imaging and environment-monitoring satellites, sonobouys, and autonomous robotic dolphins perpetually roaming the world's oceans, it was up to ships and crews to do the often perilous work. Even with the aforementioned remote sensing technology, it is still necessary for the detailed work to be carried out by humans at the study sites. Raging, swelling, stormy seas imperil the lives and well-being of everything aboard, but don't pity the scientists - they are there because they love what they are doing and thrive on the challenge. It is a seafaring tradition and trait that ...

Telemetry in Flight Testing

Telemetry in Flight Testing, November 1957 Radio & TV News - RF CafeIn-flight telemetry systems have in the past and still do play an important role in aircraft development - both manned and unmanned. Formerly almost exclusively in the domain of large corporations due to its high cost and complexity, telemetry is now performed routinely, often by people who cannot pronounce the word or even know its definition. For a mere couple hundred bucks, you can buy an off-the-shelf quadcopter 'drone' that provides a wireless link back to the pilot that includes not only a live video feed of an onboard camera, but also information on battery voltage, position, altitude, and other parameters. 'Real' model aircraft pilots have flight telemetry available via ...

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You Missed During Vacation

Click Here to See Everything You Missed During Vacation - RF CafeA lot of people have been off work since Christmas and have missed all the new items that have been posted. It would be a shame to start off the new year with such a vast knowledge deficit. Get caught up by looking on the RF Cafe December 2014 Homepage Archive.

Welcome to 2015!

Welcome to 2015 - RF CafeI said I was going to do it, and I did it. You might (hopefully) notice a major difference in the way RF Cafe looks on this first day of 2015. Changes have been made slowly throughout the last few months to enable what is now a much more clutter-free environment. Most notable is the absence of the array of vendor logos in the upper right corner of all the pages, and there is now just a single column of banner ads in the right page border. This is so for every page on RF Cafe. More than 200 pixels have been shaved off the page width without robbing any real estate from the website content. In this age of mobile Web platforms - small notebooks, tablets, and smartphones, it is imperative that websites be comfortably viewable in any format. Back ...

Electronics-Themed Comics

Electronics-Themed Comics December 1958 Radio Electronics - RF CafeBeing a great appreciator of good humor, and especially technology-related humor, I made sure to scan these comics from the pages of vintage Radio-Electronics magazines. Some of the same themes from half a century ago are still applicable today - like inventing a device that will block television commercials. There are a couple huge differences between then and now, though. For one thing, the percentage of each hour consumed by commercials has nearly doubled since 1958. A Prime Time TV show in 1958 like The Untouchables ran 50 out of 60 minutes. Shark Tank, a 2014 ...


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About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024


    Kirt Blattenberger,


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 World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

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