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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There are 1,000s of Pages Indexed on RF Cafe !
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.
Homepage Archive Pages
2017: Jan |
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2016: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2015: 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
2013: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
Click for Page 1 of the October 2015 homepage archives.
Metal vs. Glass Radio Tubes
Here is a brief synopsis on the main difference between glass and metal vacuum tubes - the metal case tubes generally exhibit higher interelectrode capacitances. Unless successfully addressed, that limits usefulness in high frequency circuits. One of the major advantageous features of metal tubes is the built-in EMI/RFI shielding both for keeping desirable fields inside the tubes and keeping undesirable fields from entering ...
Metal Radio Tubes
Metal-encased vacuum tubes were such a big deal when they arrived on the scene in the mid 1930s that two successive issues of Radio-Craft devoted the majority of print space to them. Metal tubes, as admitted by editor and author Hugo Gernsback, did not perform as well electrically as glass tubes yet, but that was attributed to the infancy of the technology. Overwhelming positives, including ruggedness, lower cost of production, longevity and other aspects would ensure that metal tubes "are here to stay." They never did even come close to replacing glass tubes. One of the most interesting statements in the article has nothing to do with metal tubes, but Mr. Gernsback's understanding ...
Cleveland Institute 515-T Slide Rule Manuals Now Available!
Thanks to Mr. Joe Hernandez (KN2A), the entire set of four manuals for the Cleveland Institute of Electronics' 515-T Slide Rule are now available online! Joe bought the manuals and slide rule on eBay as a set, and he was kind enough to scan the manuals and send them to me for posting on RF Cafe. Since posting a photo of my personal 515-T slide rules and the partial user's manual I found a few years ago, I have received many requests for the manuals. Joe is a very active Ham radio operator and invites you to visit his page on the qrz.com/db/KN2A website. He is a big time CW guy who likes to tinker. One item you really need to check out is his custom-built Mouser-40 and 3 Blind Mice CW setup ...
Electronic Noise Is Drowning out the Internet of Things
"Our increasingly connected world needs better protection against RF noise pollution. Radio-frequency noise pollution is everywhere. You can’t see, hear, taste, or smell this noise, of course. Nor can you summon it and study it at your leisure, because it comes and goes along with the movements of its sources or its victims. Start with the fact that any significant digital appliance has a high-speed clock and a digital bus, and both leak radiation profusely. Electric motors and generators generate RF noise with every small spark that jumps between their ..."
NuWaves Engineering Intros 30 Watt, S-Band RF Power Amplifier
NuWaves Engineering today introduced the NuPower 05E05A, a compact and highly efficient solid-state power amplifier (PA) module for S-band transmitters and data links. Providing 30 Watts on average, and 20 Watts minimum, RF output power, the NuPower 05E05A operates from 2,000 to 2,600 MHz for CW and near-constant-envelope waveforms. The connectorized PA module accepts a nominal 0 dBm (1 milliwatt) input signal and provides 44 dB of RF gain while operating at 40% DC power efficiency with a +28 VDC supply ...
The Element Cube
This is pretty cool. Just in time for Christmas for the man-woman-boy-girl who has everything is The Element Cube. "The Element Cube is the ultimate conversation starter. Containing over 60 elements, in one compact cube, it's the perfect centrepiece for your office desk or coffee table. From Aluminium to Zirconium, the cube has it ALL." It began life as a Kickstarter project (still is, with 11 days to go), and now has 926 backers. Its financing goal was a mere $3,804, but already has $72,105 in pledges. The high bidder gets the world's largest alloy named after him; i.e., 'Kirtonium' ...
Fun with Radio Parts
Here's another electronics-related Hallowe'en article for you just in time for tomorrow's office (or lab) party. I almost made an inane statement about how you can substitute a cellphone for the radios used in these pranks, but then I remembered that a cellphone is first and foremost a radio in and of itself. I fondly recall the old days as a technician at Westinghouse Electric when, on the evening shift, we used to get away with playing practical jokes on each other in the lab. Ours were low tech stuff like connecting a high voltage supply to someone's metal toolbox or squeezing water from a soldering iron sponge wetting bottle through a length of plastic tubing (taped under a workbench) onto a guy's crotch while he was working intently on something. You'd probably get fired or sued for such ...
Univ. of Messina Uses NI AWR Design Environment to Model Microwave Amps
NI (formerly AWR Corporation) announces that the University of Messina, Messina, Italy, microwave electronics research group uses NI AWR Design Environment™ for its modeling work. A recent project has been the design of single-stage, high-power, microwave amplifiers using complex device models for nonlinear analysis of the device behavior as well as for amplifier optimization. "NI AWR Design Environment software is a very valuable tool for teaching and research," said Professor Alina Caddemi. "It offers an impressive tuning action for model performance refining that also allows students ..."
Featured Book: Basic Radar Analysis
This authoritative new resource presents fundamentals of radar analysis including the range equation, detection theory, ambiguity functions, antennas, receivers, SP, and chaff analysis for modern radars. This book addresses details behind the detection probability equations and origins radar engineers commonly use to perform signal processor analyses. This book consolidates discussions of receiver design and analysis and treats areas of digital receivers not commonly found in other books. Packed with details on how to perform radar range equation and detection analyses, RCS modeling, ambiguity function generation and antenna pattern generation. This book also includes detailed analyses of coherent and non-coherent integration, design and analysis ...
UK to Auction Former Amateur Radio Spectrum
"Spectrum at 2.3 and 3.4 GHz that once was allocated to Amateur Radio is going on the auction block in the UK. Telecommunications regulatory agency Ofcom announced this week the steps it will take in selling off the shared spectrum it took back after the military no longer needed it. Ofcom announced in April 2014 that it was ending Amateur Radio access to significant portions of the 2.3 and 3.4 GHz bands following a year-long consultation ..."
Online Noise Figure Uncertainty Calculator by Keysight Technologies
"This [noise figure uncertainty] calculator will not get the same results as earlier versions of on-line calculator because of the different assumptions. In the most critical DUTs, the ENR uncertainty usually dominates, and the calculators will agree for the case combination of User Cal and 95% confidence specifications. When mismatch errors are significant, this calculator will be more accurate, though harder to use because of all the Specification Style and Distribution fields that can be filled in. The default settings of those fields will be optimum for most applications ...
Make Extra Profits Changing Push-Button Radios to New Frequencies
The old pushbutton radio tuners were an ingenuous bit of electromechanical wizardry. For those too young to have experienced them, operation was simple - turn the radio tuning knob to your broadcast station, pull out the lever/button, and then push it all the way back in. Done. The next time you pushed that button, the mechanism would slew the tuning dial to that position, taking the tuning elements (usually just a variable capacitor) with it. For most modern electronic radios, you program the station button by pushing and holding it for a few seconds until a beep is heard. My father never quite got the hang of tuning the pushbutton radio in his old Rambler (vacuum tubes) or even his 1972 Chevy pickup (transistorized ...
Carl and Jerry: "The Hand of Selene"
Just in time for Halloween comes this Carl and Jerry adventure. With the great popularity of zombies and the undead these days (in which I personally have zero interest), the scheme outlined here to make the 'hand of Selene' tap out answers to a soothsayer's questions would be a great scheme to use at a Halloween party. Read on to discover the tech savvy teenagers' clever implementation. ...
ARRL Seeking a Chief Executive Officer
"The Chief Executive Officer is responsible for leadership and management of staff, planning and tracking financial results and corporate compliance, maintaining effective member interface and service levels, monitoring regulatory developments and directing advocacy and public-relations efforts in support of Amateur Radio domestically and worldwide, and working with the Board of Directors, Officers, and other management toward achievement of the League's goals, strategies and plans for the betterment of Amateur Radio." This is a dream job for a qualified Ham who wants to help lead the organization to new highs.
November Issues of RF / Microwave Magazines Available Now
For some reason the titles of this latest batch of articles from RF / microwave magazines are longer than normal. I've noticed that engineering book title, including their subtitles, seem to have been growing in length over the last couple years as well. The November issues are out for Microwave Journal, RF & Microwaves, Microwave Product Digest, High Frequency Electronics, and the Test & Measurement portion of EDN ...
The Three Pain Points of the
Mil/Aero Test Engineer
- Control Crosstalk in RF/Microwave
- Using Automatic Synthesis of RF,
Microwave and Analog Circuits to
Increase Design Productivity
- LINC2 RF and Microwave Circuit
Simulator Includes Design and
Synthesis Tools <more>
Anatech Electronics Intros 3 New Duplexers
Anatech has released three new RF / microwave duplexer designs: a 2365-2435 MHz / 2445-2495 MHz cavity duplexer connectorized model, a 1950 MHz /2140 MHz ceramic surface model, and also a 3660.5-3685.5 MHz / 3760.5-3785.5 MHz Cavity Duplexer connectorized model. All can be ordered directly through their AMCrf web store ...
Notable Tech Quote: Kim Stricker
"Still have my 'RF Engineers' mug. To this day, I still ain't got a clue what all the charts and graphs on it mean, but I sure feel smart when I'm drinking coffee from it." - Mr. Kim Stricker. Kim is a fellow model airplane builder and flyer who lives and thrives in the Midwest. He is a huge aficionado of / cum lay expert on the vintage Cox engines. He and I both owned Jetco Shark 15 control line airplanes as kids; that is the model in the picture. Kim is also a licensed pilot and owns a homebuilt Pietenpol. Big motorcycles and 2nd Amendment hardware are also among his many interests. Many of his aviation photos have been featured in the local newspaper. Kim has my vote for the "Man Most Living Life to the Fullest" award (if, of course, there was one).
Star Trek-Style Tractor Beam Becomes Reality
"A tractor beam, reminiscent of the one used in sci-fi classic Star Trek, has been developed that uses sound to capture and manoeuvre objects in mid-air. The technology focuses waves of high intensity sound to grab, lift and move small items in a similar way to a human hand, and as precisely as a pair of tweezers. While it is a long way from being powerful enough to ensnare the kinds of objects seen in the TV series, it ..."
Why Be Würth-less When You Don't Have to Be?
A couple weeks ago, Ms. Heather McGhee, of Wurth Electronics Midcom, wrote to me asking about getting a listing on Vendor pages for which her company manufactured products. I obliged accordingly by adding Wurth Electronics to the Automotive Electronics, Capacitors, EMC / EMI / RFI, Hardware, Inductors, and Substrates / PCBs pages. Wurth Electronics Midcom, if you are not familiar with the company, is part of the Germany-based Würth Elektronik Group companies. Combined, they produce thousands of circuit board-based system components for power distribution, display and control panels, electronic controls. Power magnetics, EMC components, common mode chokes, capacitors, transformers, RF inductors, high current PCB terminals, printed ...
Ofcom Poised to Cancel Unrenewed Amateur Licenses
"UK telecomms regulator Ofcom has announced that it's set to start cancelling Amateur Radio licenses, possibly numbering into the thousands, that have not been "revalidated" by the holder. The effort appears to be, in part, an effort to clear dead wood from the agency's databases. Amateur Radio licenses in the UK must be revalidated every 5 years, but until Ofcom goes through the ..."
Hubble Space Telescope Galaxy Cluster
I am always in awe when looking at a photograph of one of the regions in the sky that hosts a dense cluster of galaxies - they look like fireflies. It seems unbelievable that so many other galaxies can exist, and that's only what we have discovered so far. This image from the Hubble Space Telescope (HST) is the latest in a rapidly growing collection of such clusters. Incredibly, Earth-based telescopes are now surpassing the HST in resolution - even with needing to look through miles of scintillation-inducing atmosphere. Laser-created calibration stars projected into the upper atmosphere and adaptive optics perform the magic needed to correction. The European Extremely Large Telescope (E-XLT), scheduled to see first light in 2024, will utterly blow away everything that preceded it. I hope to live that long.
Pasternack Announces New Line of Right Angle Waveguide to Coax Adapters
Pasternack, a leading manufacturer and supplier of RF, microwave and millimeter wave products, has released new lines of in-stock 1.85 mm, 2.4 mm and 2.92 mm waveguide to coax adapters with operating up to 65 GHz. These waveguide adapters are used for any number of applications such as SATCOM, wireless communications, industrial, test and measurement and defense systems whenever there is a requirement to transition from coax to waveguide or vice versa ...
Horizon House - EDI CON - CES EMC China will Co-Locate in 2016
EDI CON China is pleased to announce that the China Electrotechnical Society's (CES) Electromagnetic Technology Conference & Exhibition (EMC) will be co-located on the 4th floor of the China National Convention Center (CNCC) taking place 19 to 21 April, 2016 in Beijing. The combined event forms the largest microwave, EMC/EMI and high-speed digital design conference and exhibition in Beijing. This is a natural extension of the EDI CON China event that already covers EMC/EMI topics but will now feature a comprehensive parallel conference and expanded exhibition. EDI CON China has formed a pavilion specifically for EMC/EMI companies on the exhibition floor to congregate similar companies in one area ...
How to Use Your Radio
This 1934 edition of Tower Radio magazine was thrown in with a batch of vintage radio magazines I bought on eBay. Most of the content pertains to entertainers of the day rather than with technical issues. Reportedly, it was only sold at Woolworth's stores. Ironically, the number of households with over-the-air radio listeners today, at least as a percentage of the population if not in absolute numbers, is probably about the same as in 1934 when commercial radio broadcasting was just getting a foothold. These days, a majority of people listen to radio and podcasts via cellphone and/or Internet streaming media than from over-the-air broadcasts, even while in their cars. Organizations like the National Association of Broadcasters are ...
Optenni Lab Software & Copper Mountain Technologies USB VNA Solution
Optenni Ltd has released a new version of its matching circuit optimization software Optenni Lab™, supporting a link to Copper Mountain Technologies (CMT) USB VNAs. The link enables users to stream the measured data directly into Optenni Lab, where the user can specify the matching targets and synthesize matching circuits essentially in real time. Using this connection, users can easily test antennas and virtual matching circuit prototypes in different impedance environments ...
How Are Shortwaves Propagated? (conclusion)
What Successful Engineers Do -- Especially If You're a Woman
Nancy Golden: "You don't have to be brilliant to be a good engineer. You just need to be able to find the answers to what you need to know for the specific task at hand. That can take the form of good Internet research skills, and it doesn't hurt to have a decent technical library in your office. Knowing when to call tech support or when to strike up a conversation with a field application engineer is an important skill. To paraphrase a well-known movie quote, always be learning, because not only is technology constantly ..."
How Are Shortwaves Propagated?
Prior to atmospheric sounding rockets and orbiting satellites, all information gained and theories developed on the nature of Earth's upper atmosphere and its interaction with electromagnetic waves were purely academic, not the result of empirical data. That is not to say the theories were wrong (although some were), just that they were incomplete. For that matter, even today there is still much to be learned and, according to an excellent article in the October 2015 issue of the ARRL's QST magazine titled "Five Myths of Propagation Dispelled," there is still a lot of misinformation being believed and promulgated about shortwaves and how they travel in the atmosphere. This work is a great testament to the level of expertise that exists in the realm of Amateur Radio, and the ...
Giveaway: "Spectrum and Network Measurements" Book
"Here at Keysight, we enjoy sharing insight into the latest in electronics design, test, and measurement. Towards that end, we thought it'd be fun to give away 1000 copies of this new book to help you stay up to date on spectrum and network measurement fundamentals. First 1000 Electrical Engineers to Enter. What's the catch? If you're an engineer in the USA or Canada, simply fill in the form below. Only one entry per person, but feel free to share with your colleagues! The first 1000 names from companies in the Electrical Engineering community will be sent a book. Simple as that." DO IT NOW!
Chirality Affects Current Flow in Graphene Transistors
"The handedness or 'chirality' of electrons affects how current flows in graphene transistors, according to new work done by researchers in the UK and Russia. The team's findings could help to make better graphene-based electronic devices and could even lead to a new technology, dubbed 'chiraltronics.' Graphene is a sheet of carbon atoms just one atom thick, arranged in a honeycomb lattice. The material is unique in that each electron moves along the sheet relativistically, as ..."
An Inside Story About Metal Tubes
The advent of metal-encapsulated vacuum tubes was supposed to be the death knell for traditional glass tubes. This 1935 article from Radio-Craft spelled out the many virtues of 'metal' tube and how in short order their superiority would obviate the need - even desire - for 'glass' tubes. I'll let you read the article for the details, but want to make note of an evidently archaic term used that could potentially be really popular in today's manufacturing world if duly resurrected - 'quantiquality' (aka 'quanti-quality' or 'quanti quality'). The connotation is a process of high quantity in conjunction with high quality. The only references I could easily find to quantiquality was from late-19th-century newspaper archives. If sometime within the next few years you start seeing some ...
Nine Major League Baseball Players Who Are Engineers
Charles Murray, of Design News, has come up with yet another interesting engineering trivia subject - he dug up the names of 9 major league baseball players who have engineering degrees. He notes that since most baseball players are drafted out of high school, few have college degrees at all. Per Mr. Murray, "A 2009 Wall Street Journal analysis of a thousand or so players and managers revealed that only 26 had four-year degrees." We will, of course, expect a similar analysis in the near future for other professional sports realms; e.g., football, hockey, basketball, NASCAR ...
Free Engineering Magazine Subscriptions!
TradePub's still has an impressive collection of engineering magazines offering FREE subscriptions to qualifying applicants, which basically means you have a business address and e-mail (although it is not an absolute requirement). You might want to take a couple minutes to see what's available there. BTW, there are many other types of magazines available as well, such as for business, finance, education, sales, industry, automotive, manufacturing, and marketing. I earn a few pennies (literally) when you sign up ...
Bidding is Under Way in the 10th ARRL On-Line Auction!
"Celebrating its 10th anniversary this year, the ARRL On-Line Auction opened on October 22, and bidding already is hot and heavy. Participants are bidding on the chance to own 270 items that range from Amateur Radio transceivers, test equipment, tools, antennas, ARRL swag, memorabilia, vintage books, one-of-a-kind finds, and — in honor of the auction's 10th anniversary — the ARRL Lab team has contributed five "Mystery Junque Boxes." Some of the premier items ..."
RF & Microwave Engineering Crossword Puzzle for October 25, 2015
This week's crossword puzzle, as with all RF Cafe puzzles, uses only words pertaining to engineering, science, mathematics, mechanics, chemistry, astronomy, etc. You will never find a reference to some obscure geological feature or city, or be asked to recall the name of some numbnut movie star or fashion designer. Enjoy!
New Material Promises NSA-Proof Wallpaper
"A Utah company has a new nickel-carbon material that could help the Pentagon fight off some of its most haunting threats. Your next tinfoil hat will won’t be made of tinfoil. A small company called Conductive Composites out of Utah has developed a flexible material - thin and tough enough for wallpaper or woven fabric - that can keep electronic emissions in and electromagnetic pulses out. There are a few ways to snoop on electronic ..."
Meet the Grid Dipper... the Best Friend an R/C Fan Ever Had
A grid dip meter (aka a grid dip oscillator, dipper, or dipmeter) has long been the instrument of choice for fine tuning LC-tuned receivers for maximum sensitivity at a particular frequency. It is a simple device that oscillates at a predetermined frequency and has a meter in the grid bias circuit to measure current. When the grid dip meter tuning circuit's inductor is in close proximity to an external inductor-capacitor tank circuit that is tuned to the 'dipper's' output frequency, the grid current exhibits a significant reduction in value - hence the name grid dip meter. Modern versions no longer use vacuum tubes that have screen grids, but the name persists even with the use of transistors that, for BJTs, have a base junction and FETs, that have a gate ...
Understanding the FCC's Foreign Ownership Plan
"The FCC is proposing to update its broadcast station ownership rules to allow for greater foreign ownership, and to streamline its review and approval procedures for such greater foreign ownership <download>. Here, in a nutshell, is what is being proposed. It is necessary to say upfront that any discussion of the FCC’s broadcast station ownership rules quickly becomes mired in complexity and exceptions. Leaving aside foreign ownership, even an explanation of ..."
Properties of Purely Reactive Foster and non-Foster Passive Networks
In the year 2012 while completing his doctoral studies, Dr. Andrei Müller introduced the world's first publically available software for portraying the classical 2-dimensional Smith Chart in a 3-dimentional format. A brief report on the 3D Smith Chart software was posted here on RF Cafe, and an article entitled "The 3D Smith Chart and Its Practical Applications" was published in Microwave Journal magazine. Since that time, Dr. Müller has authored many scholarly articles on circuit theory dealing largely with complex impedances. Recently and in collaboration with Dr. Stepan Lucyszyn, the paper "Properties of Purely Reactive Foster and non-Foster Passive Networks" dealt with Foster and non-Foster passive networks with 'a strongly real function of real frequency of positive type'. It can be read in its entirety on the IET Digital Library website for ...
NASA Takes Lasercom a Step Forward
"A NASA-developed laser communication (lasercom) system demonstrated record-breaking data download and upload speeds to the moon. Now, a NASA optical physicist says he can match those speeds - plus provide never-before-achieved, highly precise distance and speed measurements - all from the same relatively small package. Called the Space Optical Communication and Navigation System, the breadboard technology is made up of commercially available components simulating both ground and space ..."
Boat Anchor Manual Archive (BAMA)
While reading a great article titled "Setting up a Test Bench" in the October 2015 issue of Nuts & Volts magazine, a reference to the Boat Anchor Manual Archive (BAMA) website reminded me that it has been many years since I mentioned it here on RF Cafe. Webmaster Kenneth Grimm (K4XL) has accumulated what has to be the world's largest collection of vintage test equipment and radio equipment manuals, all available FREE for download. "It is made possible by the generous folks who take the time and make the effort to scan and upload their manuals to the BAMA site." If you have a scanned copy of a manual either not already in Mr. Grimm's collection or a better copy of an existing one. please submit it for the benefit of others ...
Ok, here's a little dose of Ham comedy for your Friday afternoon. It's a little bit kooky by today's standards, but in 1940 the style of humor it fits right in. This could easily have been the plot in an old TV show like The Honeymooners, or one of the radio situation comedy (sitcom) programs like The Life of Riley. QRM, by the way, is Ham lingo for man-made signal interference, as opposed to QRN, which is atmospheric or 'natural' signal interference. Enjoy ...
International Model 66 and 666, 6-Tube Superhet Radio Service Data Sheet
This Radio Service Data Sheet covers the International Model 66 and 666, superheterodyne receiver. Most - if not all - electronics servicemen had subscriptions to these magazines because they were a ready source of not just these service sheets, but because of the extensive articles offering advice on servicing radios and televisions. In fact, many electronics manufacturers had a policy of supplying service data only to bona fide ...
Ford-Philco Radio, Model FT9, 6-Tube Auto-Radio Receiver Data Sheet
This Radio Service Data Sheet covers the Ford-Philco radio model FT9, 6-tube auto-radio receiver. A large list is included at the bottom of the page of similar documents from vintage receiver schematics, troubleshooting tips, and alignment procedures. They were originally published in magazines like Radio-Craft, Radio and Television News, Radio News, etc. I scan and post them for the benefit of hobbyists who restore and service vintage electronics ...
New Batteries: Progress or Confusion?
Battery technology experienced a major technology evolution in the late 1950s similar to the one that took place in the late 1990s. Prior to the 50s, most common portable batteries were of the carbon-zinc type and were not rechargeable. Nickel cadmium (NiCad) cells existed, but were not in widespread use largely because little was known about the chemistry and how it responded to various charge and discharge cycles. Mercury, NiCad, nickel metal hydride (NiMH), alkaline-manganese, began gaining popularity in applications requiring longer battery life and more consistent discharge characteristics. In the 2000s, lithium polymer (LiPo) and lithium ion (LiIon) underwent a similar evolution. Still, all the aforementioned battery types are in use today ...
An Automatic Program Censor
The effort to block advertising on radio broadcasts has been going on for about as long as advertising has been in use, as evidenced by this 1934 article in Radio-Craft where a 'robot' advertising silencer' device is presented for removing 'superfluous advertising.' Headlines from a few weeks ago announced Apple's program for blocking ads that appear on websites, causing a big to-do about how all the 'free' content would be jeopardized since it is the advertisers who pay for the music and other programming to be delivered to the user. Without the convenience and economy of software to do the job in 1934, however, fairly complex discriminator circuits were used to detect and mute the 'garrulous announcer or advertiser' between regular programming. It's pretty funny to ...
MathWorks Introduces WLAN System Toolbox for MATLAB
MathWorks introduced WLAN System Toolbox, providing standard-compliant functions for the design, simulation, analysis, and testing of wireless LAN communications systems. WLAN System Toolbox expands capabilities of MATLAB for wireless development by providing configurable physical layer waveforms for IEEE 802.11ac and 802.11b/a/g/n standards. The system toolbox provides reference designs to enable exploration of baseband specifications, and demodulate and recover signals. Users can also study the effects of RF designs and interference sources ...
New Titles Added for Winners of the RF Cafe Book Drawing
New options have been added for winners of the monthly RF Cafe Book Drawing. Amongst them is Spectral-Spatial Classification of Hyperspectral Remote Sensing Images, by Jon Atli Benediktsson (graciously provided by Artech House). "This comprehensive new resource presents recent developments in the classification of hyperspectral images using both spectral and spatial information, including advanced statistical approaches and methods. The inclusion of spatial information to traditional approaches for hyperspectral classification has ...
October 21, 2015
It's Back to the Future Day!
If you watched Back to the Future Part II, released to theaters in 1989, you might recall that October 21, 2015 was the date Marty McFly dialed into Doc Brown's DeLorean time machine in order to fix the future 'him' and, more importantly, his kids. BBC News published an article titled "Back to the Future II: What Did It Get Right and Wrong?" Among them are silent (electric) cars, converting garbage into energy, and large screen home televisions. Both Lexus and Hendo have recently made news with its prototype 'hover board.' Oh, another thing the film got right was that in 2015, when you get older, you look older - heavy sigh.
RFS to Showcase at 5th Annual Canadian Wireless Trade Show
Radio Frequency Systems (RFS) is a global wireless and broadcast infrastructure specialist which designs and manufactures cable, antenna and tower systems, as well as active and passive RF conditioning modules, providing total-package solutions for outdoor and indoor wireless infrastructure. At the 5th Annual Canadian Wireless Trade Show, RFS will showcase a variety of its end-to-end infrastructure solutions, including: Low-inductance HYBRIFLEX cables that feature special wiring to reduce overall cable inductance ...
NI | AWR Sponsors "Breakthroughs in Phased Arrays and Radar" Webinar
NI (formerly AWR Corporation) announces that it is sponsoring "Breakthroughs in Phased Arrays and Radar" as part of Microwave Journal's RF/microwave technical education webinar series. Moderated by Dr. Eli Brookner, IEEE Life Fellow and former radar expert at Raytheon, this webinar examines the significant improvements in radar capabilities made possible by the advent of the active phased array antenna. Wednesday, November 4, 2015 8 AM PT/11 AM ET ...
FM Broadcast Licenses Issued to First 15 Stations
This edition of National Radio News announces the FCC's approval of the first 15 FM broadcast licenses for stations spread across the country. It is also the first issue following America's entrance into WWII and includes a question from a Ham regarding whether simply listening to radio reports was allowed. As you might know, the FCC prohibited amateur radio operators from transmitting for any reason during both World War I and World War II. The reasons given were clearing the airwaves to make monitoring easier, to prevent intentionally encoded messages from being sent, and to keep homeland status information from being broadcast. Homeland status could be ascertained by assimilating reports of who was being drafted and entering service and ...
Notable Tech Quote: Heathkit
"Sometime in the past 30 years, electronics got so complex and automated that product manufacturers took control away from us, and radio stations became a number. But a radio station is not a number. It is a place, and it has 'width.' How wide it is depends on how far away you are from the station, how powerful it is, and how your radio was designed." - Heathkit Explorer Jr.™ webpage note.
Checkers by Radio
Game playing with a remote opponent is routine these days thanks to the Internet, but a couple decades ago it was not quite so easy. A checkers or chess match via telephone, snail mail, or even fax machine were the venues available to the common man, but Hams had another means - radio! Using either Morse code or voice and a playing board set up like the one shown in this article, two players could easily match wits anywhere in the world where signals could be exchanged. Evidently the participants could get so wrapped up in the game that they risked forgetting to broadcast their call signs at the legally required interval (every 10 minutes), so author Utterback provides a friendly ...
Advanced Test Equipment Corporation Needs a Technical Marcom Specialist
(Update)Advanced Test Equipment Corporation is a world-wide Hi-Tech equipment rental company located in Sorrento Valley. We are seeking a technical person or engineer to write technical articles and web content for our website on Test & Measurement equipment. A background in engineering or test and measurement equipment is a plus! Responsible for researching, writing and editing, summarizing data from data sheets to transform intricate technical content into user friendly specs. This position requires in-depth knowledge of test & measurement equipment as well ...
Light Goes Infinitely Fast with New On-Chip Material
"In the 21st century, photonic devices, which use light to transport large amounts of information quickly, will enhance or even replace the electronic devices that are ubiquitous in our lives today. But there's a step needed before optical connections can be integrated into telecommunications systems and computers: researchers need to make it easier to manipulate light at the nanoscale. Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences have done just that, designing the first on-chip metamaterial with a refractive index of zero, meaning ..."
Please Welcome Reactel as RF Cafe's Newest Supporter !!!
Reactel has become one of the industry leaders in the design and manufacture of RF and microwave filters, diplexers, and sub-assemblies. We have established a full line of filters of all types. Latest CAD/CAM methods and equipment used in design and manufacturing. Many filter designs are available in either tubular, rectangular, or waveguide packages, connectorized or surface mount, and standard or high power versions. Frequencies up to 50 GHz, depending on filter type.
FCC Seeking User Comments on New Beta Website
"As part of an ongoing research and design project 'to dramatically improve the usability and functionality' of its website, the FCC has debuted a new prototype website and wants to know users think about it. The FCC's 2011 website re-design was not well received, and the Commission has continued to maintain its previous, much-older website design in tandem with the newer one. 'You spoke, we listened,' FCC Chief Information Officer David Bray said in an ..."
Listening to the World
During and immediately following World War II, the 'Monitoring Service' of the British Broadcasting Corporation (BBC) relentlessly listened to radio broadcasts from all over the world in order to be able to break headline news and, if appropriate, pass strategic military information on to Allied command centers (who were simultaneously doing their own monitoring). This article tells of some of the more significant messages intercepted and how the facility was a highly guarded secret in order to prevent sabotage and infiltration. At the height of activity, 32 languages were being transcribed into English daily, consisting of more than ...
P1dB Announces Broadband, 0.5 to 18 GHz SMA Couplers
P1dB, an RF and Microwave component supplier, announces in-stock availability of a series of broadband RF couplers that operate from 0.5 to 18 GHz. The SMA Directional couplers, series number P1CP-SAF-R518G30W, come in 10 dB, 20 dB and 30 dB values as standard items, but other values are available upon request. The Directional couplers are designed to handle 30 watts of input power ...
The 'Kit' Has Finally Been Put Back in Heathkit™ !
I signed up as a 'Heath Insider' about a year ago when news first broke about Heathkit's intention to finally, after a couple decade hiatus, begin producing built-it-yourself electronics kits again. The Explorer Jr.™ is a basic capacitor-tuned AM radio kit that comes complete with everything needed to build it. Why not a digitally tuned synthesizer with an LCD display? Company president Andy Cromarty promises many more kits to follow, with all being in the classic Heathkit tradition of high quality parts and well-written, illustrated, step-by-step instructions. It will be a continuation of their "You Can Build It. We won't let you fail." motto. An e-mail arrived a few days ago stating the following: "Here's a quick summary of what we've quietly been doing at Heathkit during the past year: We assembled a terrific team of very talented ...
RF Cafe Website Categories Crossword Puzzle for 10/18/2015
OK, I admit that this week's crossword puzzle is a little self-serving and self-promoting, but what the hey. All of the clues with an asterisk (*) after them are categories in the table of contents at the tops of RF Cafe website pages, so that should help a bit. To make it even easier, they are all on the 'Main' TOC menu. All the rest of the words, as usual, are related to engineering, science, mathematics, etc ...
MECA Intros 2 New Compact Low-PIM Attenuators
MECA's new compact 50 watt and 100 watt Low PIM Attenuators (-160 to -165 dBc typical) feature industry leading thermally stabilized low PIM distortion performance (low thermal noise). In addition all of the terminations cover 0.698 – 2.700 GHz frequency bands. Also available in: Type N, 4.1/9.5, 4.3/10.0, and 7/16 DIN models both within connector series and mixed series configurations ...
Signal Splitting Pads
Designing resistive impedance-matched signal splitting networks is nowadays mostly done with the assistance of computer software. In fact, odds are pretty high that the designer either has no idea what the formulas behind the 'magic' are, or at least it has been a very long time since working them with pencil and paper. There's no shame in that, though, just as there is no reason to expect someone using a cellphone must know the intricacies of the internal circuits or the network to which it is connected. We've moved past that. For those of us who still appreciate a refresher on the behind-the-scenes calculations being performed at lightning speed ...
PMI Releases 8 New RF & Microwave Devices
Planar Monolithics Industries (PMI) has just released 8 new devices for the RF and microwave market. Among the list is an 18-40 GHz successive approximation log video amp, an 8-18 GHz high speed 5-bit frequency translator, a 30 MHz to 26.5 GHz LNA, and a 10 MHz - 6 GHz portable amplifier. PMI has one of the industry's largest selections of RF and microwave products spanning from DC to 40 GHz ...
Explore RF Online Course as December Drawing Prize Option
A 1-year subscription to the very popular Explore RF online course, created and hosted by Dr. Francesco Fornetti, will be available again as an option for the December 2015 RF Cafe Book Drawing. Dr. Fornetti graciously provided two subscriptions last year shortly after first publishing his Conquer RF Frequency book that accompanies the course. Both were selected by winners immediately - passing up an otherwise great array of other high quality, recently published engineering books.
Free Tutorial: Error Vector Magnitude Measurements Fit for 5G
Keysight Technologies, via the IEEE ComSoc folks, has provided a free online tutorial titled "Error Vector Magnitude Measurements Fit for 5G." Summary: Error vector magnitude, EVM, measurements have been the mainstay of modulation performance analysis for more than twenty years. Each new technology has defined a specific measurement to suit the characteristics of the physical layer signal. The interest in signals for 5G that are much wider bandwidth, operating at much higher frequencies means it’s time to draw a comparison between the different waveforms ...
Radio-Radar-Sonar in Naval Applications
World War II was the 'necessity' that elicited the 'mother of invention' activity responsible for many huge leaps in technology - not the least of which was electronic verbal and non-verbal communications. Along with radio and radar, Loran had become a major means of ocean and air navigation. A fair description of the operational details, including timing diagrams, is included in the text. Loran-A, the original system as it came to be known, was fully decommissioned in 1980, thereafter supplanted by Loran-C. With the advent of GPS, Galileo, and Glonass navigation systems and their low and their low equipment and installation costs ...
Anti-Drone Rifle Shoots down UAVs with Radio Waves
"While the US military continues to develop new and awesome ways of blowing aerial drones to smithereens, not many of these systems can easily be adapted to use in the civilian realm. That's why Battelle has developed the DroneDefender, a shoulder-mounted rifle that knocks UAVs offline with a barrage of radio waves. It easily and reliably neutralizes the threat." The weapon weighs roughly 10 pounds and can target drones up to 400 meters away ..."