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.
Page 2 of the November 2015 homepage archives.
Electro-Photonics Intros 1,000-2,000 MHz SMA Hybrid Coupler
LLC announces the availability of a connectorized hybrid coupler: Q3XG-1500R-SMA. Our new Q3XG-1500R-SMA 90° hybrid coupler operates from 1000-2000 MHz, dissipates 65 W,
and offers excellent coupling flatness and isolation for the most critical applications. This coupler has an extremely small package of 1.60
x 1.10 inches (40.64 mm x 27.94 mm). The Q3XG-1500R-SMA is manufactured in the USA, and is RoHS compliant
Microwave & RF Engineering Crossword Puzzle for November 15, 2015
Microwave and RF Engineering crossword puzzle contains
the usual collection of science, math, and engineering terms. Never will you be tasked to recall the names of idiotic Hollywierd celebrity's
name or the kingdom of some obscure civilization in Krapistan or Moronia. Enjoy.
Friday Quiz: Signal Conditioning
Martin Rowe, EE Times' senior technical editor, has posted another in his series of Friday quizzes, this time on
Signal Conditioning. "Most sensors can't
connect directly to a measurement system because the signal amplitudes are too low or are nonlinear. Some sensors also require excitation, in
the form of a power supply. The questions for this week's quiz test your knowledge of that you need to condition several types of sensors. To
find the answers and learn more about physical ..."
Google Self-Driving Car Pulled over 'For Driving Too Slowly'
When one of Google's self-driving vehicles
is pulled over, who gets the ticket? The passenger or the car? The question was asked across the Internet on Thursday, after a police officer
stopped one of the gumball-machine-shaped vehicles on El Camino Real. In a blog post, the Mountain View Police Department said the officer noticed
traffic backing up behind a slow-moving car in the eastbound No. 3 lane, near Rengstorff Avenue. The vehicle was traveling at 24 mph in a 35
mph zone. "As the officer approached the slow-moving ..."
AWR Design Forum/German User Group Event Announced
AWR Corporation) announces the agenda has been set and registration opened for its annual combined AWR Design Forum
(ADF) 2015 / German User Group
meeting being held November 26, 2015 at the NI European Headquarters in Munich. Celebrating its fifth year, ADF is an open forum that brings
together NI AWR software customers, partners and microwave/RF engineering professionals to learn, network and collaborate on the design of today's
microwave and RF circuits and systems. Highlights of ADF include technical presentations featuring NI AWR Design Environment™ and select customer
and keynote ...
Mac's Radio Service Shop: Barney is a Big Boy Now
let the title fool you. This is not a "bees-birds-and-flowers routine" being provided to Barney by his boss, Mac. It turns out to be a brief
introduction into the fine art of
problems in radio and television circuits. As is usually the case, while the specifics of the scenarios Mac describes might not apply to
your challenge at hand, the general philosophy always does. It is basically the old process of elimination where after rapping components mechanically
and/or heating or cooling them in hopes of observing a tell-tale change in performance, the next step is to divide the suspected circuit portion
in half (electrically, but sometimes also physically) and look in one direction. If the problem isn't there, then
RCD is vertically integrated to design, manufacture, and test high-quality
RF components - filters, amplifiers, couplers, dividers, attenuator - using a variety of
manufacturing processes. Specific RF or mechanical requirements to suit customer needs addressed, including high port-to-port isolation requirements,
low ohmic losses, high power, and PIM levels. Components currently offered in 70 MHz – 5 GHz frequency range. Decades of applicable industry
experience in this particular field and look forward to working with you towards a comprehensive solution to your specific needs. +420-466-415-755.
Please Welcome Asian Circuits as a New Advertiser!
With headquarters in Dublin,
CA, and production facilities in Shenzhen, China, Asian Circuits Inc., a contract PCB
assembly company , is an expert in mid- and high-run printed circuit card assembly. Its staff of 600 consists of 450 associates in PCB fabrication
and 150 in circuit board assembly. It is an ISO9001, IPC-A600 and IPC A610 compliant company. • PCB Online
Quote: An instant PCB price can be quoted after selection of a few options. • PCB Assembly Quote: An additional instant quote for the cost of
labor. • BOM Pricing: Get price within 24 hours. Please take a few moments to visit Asian Circuits today in appreciation of their support
Chinese Scientists Unveil New Stealth Material Breakthrough
"Planes and warships just
got a lot harder to see with microwave radar. A group of scientists from China may have created a stealth material
that could make future fighter jets very difficult to detect by some of today’s most cutting-edge anti-stealth radar. The researchers developed
a new material they say can defeat microwave radar at ultrahigh frequencies, or UHF. Such material is usually too thick to be applied to aircraft
like fighter jets, but this new material is thin enough for military aircraft, ships, and other ..."
Bird Technologies Model 614 Series Digital Signal Boosters Increase Coverage
Bird Technologies, a leading
provider of RF components, subsystems, test equipment, and services, today introduced the 614 Series digital signal boosters
designed to increase the signal strength of land-mobile and public safety communications systems operating at either 450 to 470 MHz or 470 MHz
to 488 MHz. The highly configurable system combines the benefits of programmable digital RF filters, the cryptographic and other security benefits
of the SNMPv3 control protocol, browser-based configuration and management, the ability to view changes to filter characteristics while viewing
Bizarre Trend Sees People Transform Themselves into Glowing Cyborgs
If you dread the thought of your kid
coming home some day with a mere tattoo or body piercing, it will seem tame compared to this. "A group of 'biohackers' in Germany has implanted
LED lights under their skin. The men each had a Northstar V1 chip - which is about the size of a large coin - implanted into their hands. The
chip features a ring of LED lights and is designed to be able to light up tattoos from beneath the skin, emulating the bioluminescence of jellyfish
Basic Antennas: Understanding Practical Antennas and Designs
When I grow up, I want to be like Joel Hallas (W1ZR)
- at least when it comes to a fundamental comprehension of antennas and transmission lines. Mr. Hallas' "The Doctor Is In" column is the
first QST feature I read each month. His book, "Basic
Antennas, is a comprehensive introduction to antennas--basic concepts, practical designs, and details of easy-to-build antennas. You'll
learn how to make antennas that really work! This book will provide a foundation in antenna theory and design necessary for anyone undertaking
more advanced topics such as those presented in The ARRL Antenna Book. Includes: Dipole Antennas, Antenna Impedance, Transmission Lines, Practical
Two Element Arrays, Wideband and Multiband Antennas Reflector Antennas, Yagis for HF
Saelig Introduces Economical 3 GHz RF Signal Generator Series
Saelig Company has announced the availability of Rigol DSG800 RF Signal Generators, with output frequencies from 9 kHz to 3.0 GHz.
They provide an economical RF signal source with a maximum output of +20 dBm and frequency resolution of 0.01 Hz at any frequency.
Featuring very low SSB noise of -115 dBc/Hz, they feature a highly stable internal clock (<2ppm standard, 5ppb optional) for creating
high performance RF test signals. Operation is easy and intuitive, guided by the 3.5" color LCD with its logically grouped controls
Many Thanks to Empower RF Systems for Continued Support!
Please take a moment to visit
Empower RF Systems to see whether their top-notch RF power amplifier systems
would be useful in your next project. Empower RF Systems is a global leader in power amplifier solutions. Products include high power RF amplifier
modules, amplifier systems, and custom designed amplifiers. Investments in both hardware and software engineering are yielding next generation
products with significant size, weight, and interface functionality advantages over legacy products in the market ...
In Remembrance... Veteran's Day 2015 11th Month, 11th, Day, 11th Hour
This Veterans Day(Remembrance Day in
Australia) tribute is by Canadian citizen
Terry Kelly. A Pittance of Time
was written after an experience he had on Veterans Day in 1999. Terry went blind at an early age, but has excelled as an athlete and a musician.
It is done in the finest Celtic tradition … and, of course, Lee Greenwood's- God Bless the USA , written 7 years before 9/11.
"Take two minutes, would you mind? It's a pittance of time, For the boys and the girls who go
over. In peacetime our best still don battle dress, And lay their lives on the line. It's a pittance of time."
A New English All-Metal Tube
The saga continues... Please bear with me even if you have no interest in the
much-hyped (at the time) history of the advent of
all-metal vacuum tubes in the mid 1930s.
They were predicted to make glass-encased tubes obsolete. It never happened. Believe it or not, there are a few folks out there
(like moi) who like reading about the history. Posting this on the RF Cafe homepage helps the search engines find
and register it faster. If you also happen to care, then you might be interested to know this article was
Notable Tech Quote: Jeff Hester
"The postmodernists are right about science, just up to the point that they are terribly wrong. Let me offer a
piece of advice. Never get on an airplane designed by a postmodernist! Scientific knowledge deserves special status for an obvious reason: Science
works. When you need real answers, nothing else even comes close." - Jeff Hester, columnist, November 2015 Astronomy
A Radio Frequency Application of Critical Damping Theory and Practice
magazine is a great source for technical articles that cover the realms of electrical, electronics, and RF & microwave engineering. I visit
their website a few times each week in search for headlines and relevant pieces like this one authored by Ken Javor. "A Radio Frequency Application
of Critical Damping Theory and Practice" includes many photographs of his test setup and screen captures from his Rohde & Schwarz EMI
Test Receiver measurements. "EMC is sometimes termed the study of secondary effects that are ignored in college curricula. This investigation
hinges on subtle effects mostly ignored during EMI testing ..."
Many Thanks to Windfreak Technologies for Continuing Support!
Please visit Windfreak
Technologies now to determine whether their frequency synthesizer products can help your project. Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products such as RF Signal Generators, RF Synthesizers, RF Power Detectors, RF Mixers, RF Upconverters and RF
downconverters. Worldwide customers
include Europe, Australia, and Asia.
Hedy Lamarr Google Doodle
Today's Google homepage features one of their famous Doodles that honors the
accomplishments of Austrian-born actress Hedy Lamarr. You might wonder why I would point this out
on an engineering website. Here's why: Aside from being one of the most well-known film stars of her era, Ms. Lamarr was also an inventor and
received U.S. patent number US2292387 jointly with composer / pianist Antheil George for a "Secret Communication
System." We refer to her invention today as frequency-hopping spread spectrum. Given that Google is heavily invested in spread spectrum
technology and the company is staffed with some of the world's top engineers, it is no wonder the Google Doodle dedicates more than half of
the presentation to Hedy Lamarr's technical accomplishments ...
The Man Who Made 'The World's First Personal Computer'
"When the definitive history of the personal computer is written, familiar and
historic names such as Olivetti, Apple, IBM, will all be given recognition for their innovations of the 1960s and 1970s. But will future generations
remember visionary John Blankenbaker, and his ground-breaking invention,
the Kenbak-1 Digital Computer? It was a machine that first went on sale in 1971 and is considered to have been the world's first 'commercially
available personal computer,' coming on to the market some five years before Apple 1 ..."
A Stationary Reversible Beam
vertical antenna can have a significant advantage over a
horizontal antenna from a maintenance perspective, since, depending on how high the antenna is mounted off the ground, the 'business end' where
electrical connections are made are more accessible. The configuration shown here would be difficult to implement if a mast rotator is to be
used because of the stabilizing guy wires on the lower frame. Although it should be possible to achieve the necessary rigidity without guys
by using an aluminum or fiberglass tubing frame rather than wood, preventing weathervaning in strong winds could prove difficult. A nifty feature
of this 'reversible beam' antenna is that reciprocal directivity is implemented simply by swapping out a short
Hybrid Simulation for Electrically Large Aerospace Platforms Seminar
CST and Davide Tallini
offer this free seminar on Thursday, December 3, 2015 at 11:00 am EST. "Starting from the
free-space radiation performance of each antenna, the problem to predict the global installed radiation pattern, antenna to antenna coupling
in presence of a spacecraft has to be treated in order to identify potential blind areas or interferences caused by the neighboring structures.
The prediction of electromagnetic field scattered in complex environment is usually a hard task since the solution cannot be generally expressed
in a simple and/or closed analytical form
Giant Horns Allow You to Hone in on Sounds Around You
"Art installations are being more interactive as they seek to not only entertain but teach. Dutch artist Jeroen
Bisscheroux's latest installation is no to exception to this as his massive megaphones pick up on all the surrounding sounds of the Vincent
van Gogh College in Assen, the Netherlands. The art piece entitled TOON, consists of three large metal horns facing different
directions but connected by a central pipe collecting all the acoustics. The central pipe ..."
How Dependable Are Your Meter Readings?
people are still using analog meters for making voltage, current, resistance, and power measurements these days; however, for those who are
and even for those using digital readout meters, there are valuable lessons to be learned from this article on factors that can affect the accuracy
of your measurements. Whenever you make a
measurement with any kind of instrument, the first step to take in minimizing the chances of inaccurate readings is to be certain the instrument
is in good working order and is known to be reasonably accurate. If it is battery powered, know that low battery voltage can cause erroneous
readings in both analog and digital meters, so beware. If you are making a measurement to verify a known
Wireless Engineering Crossword Puzzle for November 8, 2015
Wireless Engineering crossword puzzle contains the usual collection
of science, math, and engineering terms. Also included are a couple topics that have been in the technical news headlines lately and the names
of two new companies advertising on RF Cafe (clues labeled with asterisk *). Enjoy
New Slant on Semiconductor Characterization
"From laptops and televisions to smartphones and tablets, semiconductors have
made advanced electronics possible. These types of devices are so pervasive, in fact, that Northwestern Engineering's Matthew Grayson says we
are living in the 'Semiconductor Age.' 'There are
so many applications for semiconductor materials, so it's important that that we can characterize these materials carefully and accurately.
Non-uniform semiconductors lead to computer chips that fail, lasers that burn out ..."
Please Welcome Electro-Photonics as a New Advertiser!
Electro-Photonics LLC is a global supplier of RF &
Microwave components. Their products include SMT hybrid and directional couplers, wire bondable passive components, and very useful test
boards for evaluating components. The Electro-Photonics team can support your small R&D design requirements with RF & Microwave test
fixtures and save you valuable design and characterization time. Please take a
little time now to visit Electro-Photonics' website to see whether they can help your effort.
While you're there, check out their TRL Calculator.
Graphene Could Take Night-Vision Technology Beyond 'Predator'
"Movies such as 1987's 'Predator,' in which an alien who sees in the infrared
hunts down Arnold Schwarzenegger and his team, introduced a generation of sci-fi fans to thermal imaging. Since then, heat-sensing devices have
found many real-word applications but have remained relatively expensive and rigid. But a new development featuring graphene, reported in ACS'
journal Nano Letters, could lead to a flexible, transparent and low-cost infrared vision system ..."
Congrats to October Book Drawing Winner Andy T. !
Andy T., from Wilson, Wyoming, was one of the
October book drawing winner, Andy wisely selected
EW 104: EW Against a New Generation of Threats, by David L. Adamy (graciously provided by
Artech House). Each month I randomly draw a name or two from the list
of people who have purchased my software during the month. I even pay shipping
so the book are truly free to winners. My other, Sylvain F., from Blagnac, France winner has not replied yet.
New Radios Not Guaranteed to Meet FCC Emissions Specifications
QST columnist Larry Wolfgang had an eye-opening report in his November 2015 "Technical
Correspondence" column. He discusses the in-situ testing of handheld transceivers at the ARRL Hamvention. ARRL Laboratory Engineers did a spurious emissions test using a calibrated setup to anyone wanting
to submit his/her unit for evaluation. To make a short story even shorter, Most brands' handset passed handily, but two brands in particular
- Baofeng and Wouxun - consistently for the last 4 years had a significant percentage of noncompliant units in bands below the 225 MHz
(spec cut-off). Some were really bad. Don't shoot the messenger. Caveat emptor!
Pair of Mesh Reflectors Boost Navy’s Satcom Capacity 16x
"A pair of 'mesh reflectors' used to boost
capacity on the U.S. Navy's space-based mobile phone network have deployed successfully on the newest satellite in the constellation, antenna
manufacturer Harris Corp. announced this week. The unfurling antennas were launched September 2 aboard the fourth payload in the Navy's constellation
of Mobile User Objective System (MUOS) satellites. Built by Lockheed Martin, the MUOS ..."
RF Filter Applications for Dummies®, RF Filter Technologies for Dummies®
(formerly RFMD) has published two new books under the very popular "... for Dummies®" instructional
series produced by John Wiley & Sons, Inc. One is titled "RF Filter Applications for
Dummies®" and the other is "RF Filter Technologies for Dummies®."
As you might expect, these books are basically advertisements for Qorvo,
but that's OK because they contain useful information and they are made available for FREE. Per the Qorvo website: "These two books explain
how various filtering technologies, including Qorvo's LowDrift™ and NoDrift™ filters, address unique
The Mysteries of the Van Allen Belts
"In 1958, US satellite Explorer 1 transmitted valuable information about radiation back from above the Earth. Professor
James Van Allen discovered a group of
charged particles which were creating two distinct belts of radiation. These belts appeared to be protecting the planet from harmful space particles
and are now known as the Van Allen radiation belts. Scientists wanted to know more about it and that’s when things got weird. They sit in a
toroidal or donut shape around the planet but the ..."
An Excellent Envelope Tracking Video Tutorial by Radio-Electronics
of the Radio-Electronics website, has produced an excellent video tutorial on
the subject of envelope tracking usage in modern radios (aka cellphones).
A combination of clear diagrams, interviews with design engineers, and live screen shots of signal behavior is used to effectively illustrate
the principles without going into gory mathematical detail. If you have ever wondered why cellphone power amplifier (PA) companies like Qorvo
(RFMD), Skyworks, and Peregrine also make and sell DC-DC converter and DC power management ICs, this video will answer the question
Researchers Develop Fastest and Most Flexible Silicon Phototransistor Ever
RR Media - Teleport has an opening for an RF Engineer. The position requirements include but are not limited to: Planning, execution,
control and maintenance of technical TX (uplinks) & RX (downlinks.) Independent worker; capable of leading projects; shows initiative in
a challenging and dynamic work environment; testing, QA & deployment of new technologies; Supervision and execution of antenna building
and dismantling; Installation and maintenance of RF cables (indoors and outdoors); installation of external downlink gear and wiring it to the
compression room and uplink gear from the compression room
Measuring Distortion in Audio-Frequency Amplifiers
As with so many topics, the basics of something like making
harmonic distortion(and other forms of distortion) in an amplifier circuit has not changed much - if at all - over the decades. Test
equipment and circuits being measured get more advanced, but especially if you are new to the concept, articles like this one on audio-frequency
distortion from a 1941 edition of Radio-Craft are as useful today as it was when it was written
ΞΞ RF Cafe App v1.00 ΞΞ Now Available
It's been a lot of work with a steep learning curve, but at
long last the first RF Cafe App is now available for download
from the Google Play website! An iPhone version will probably be created if my motivation level is elevated enough by a huge number of downloads
for this Android version. This first release is meant to 'test the waters' for the usefulness of an app whose purpose is to provide reference
material rather than a collection of calculators. Whether you are in the lab, at your desk doing design work, or operating in the field, there
are times when you need data. These first few screens are some of the most often needed information. If enough support is received, the RF Cafe
App can be greatly expanded into a vast volume of formulas, sketches, tables, definitions, and other encyclopedic content not
Wizard: The Life and Times of Nikola Tesla - Biography of a Genius
"Seifer's vivid, revelatory, exhaustively
researched biography rescues pioneer inventor
Nikola Tesla from cult status and restores him to his rightful place as a principal architect of the modern age. Based largely on firsthand
documents including Tesla's writings, his patents and those of competitors, it credits the Croatian-born Serb, who moved to New York in 1884,
with the invention of the induction motor, long-distance electrical power distribution, fluorescent and neon lights, the first true radio tube
and remote control, besides making vital contributions to the technology underlying television, wireless communication, robotics, lasers, the
facsimile machine and particle-beam weaponry anticipating the space-based "Star Wars" defensive shield. Though often depicted as a recluse,
flamboyant nouveau-riche Tesla
Precision Connector, Inc., Added to RF Connector Manufacturer Page
Inc., located in Franklin, IN, has been added to the RF Connectors,
Adapters, Sockets, & Terminal Blocks Manufacturers & Services listing page on RF Cafe. Precision Connectors designs and manufactures
precision RF and Microwave coaxial connectors for both military and commercial applications. A full line of common coaxial connectors are available,
including 1.0mm, 1.8mm, 2.4mm, 2.92mm, 3.5mm, SSMA, SMA, SMPM, SMP, TNC, and N, along with in-series and inter-series adapters. Please contact
them at 317-346-0029 for assistance ...
Why Every GPS Overestimates Distance Traveled
"Runners, mariners, airmen, and wilderness trekkers beware: Your
positioning system (GPS) is flattering you, telling you that you have run, sailed, flown, or walked significantly farther than you actually
have. And it’s not the GPS’s fault, or yours. Blame the statistics of measurement. Researchers at the University of Salzburg (UoS), Salzburg
Forschungsgesellchaft (SFG), and the Delft University of Technology have done the math to prove that the distance measured by GPS over
An 18 Metal-Tube All-Wave Superhet
As I have written in a couple articles recently, there was a huge push in the mid 1930s to adopt the revolutionary
new metal-encased vacuum tubes over
established glass-encased tubes. Today, interest in vacuum tube amplifiers is building among audio enthusiasts both from a nostalgic perspective
and from a long-perpetuated belief that sound from vacuum tube circuits have a distinctively richer quality than that of solid state devices.
I post this stuff for the benefit of those who otherwise might not be able to find the information otherwise. Your patience indulgence is appreciated
Glass-"Metal" Tube Shield
on vacuum tube based USAF air traffic control radar and radio systems, and having seen many tube television and radio sets I never recall seeing
one of these form-fitting metal shields.
All the ones I've seen are simple cylinders that slide over the tube and either twist into a receiving rim slot or they have spring metal fingers
that grab the glass envelope. As you might guess, utilizing a metal shield around a tube for anything other than a low frequency application
like an audio amplifier or poser supply requires circuit design that takes into account the capacitive effects of the large metal plates
Notable Tech Quote: Craig Young
"Anything that's always connected, always sending data—that's something a nearby
attacker can latch on to," says Craig Young, senior
security researcher at the risk management firm Tripwire, as quoted in October 2015 issue of This Old House magazine column "How to Hack-Proof Your Smart Home."
Top 100 Government (Defense) Contractors for 2015
Technology just published its list of the Top 100
Government Contractors for 2015 in terms of total taxpayer dollars awarded for contracts in IT, systems integration, engineering, and professional
services (i.e., defense).
Total contract value for 2015 is $98.5B. That's a lot of wampum, but the amount is down about 25% from 2011 levels. Consider that the total
Federal welfare budget
in 2013 was about $1Trillion (10x the above).
Alion Science & Technology Has an Immediate Opening for an RF Engineer
Leads projects and provides technical
direction to and coordinates the efforts of engineers and technical support staff in the performance of assigned projects. Develops and applies
advanced Radio Frequency engineering theories,
methods and research techniques in the investigation and solution of complex technical problems and projects. Supports senior technical level
personnel and program managers in the planning, oversight, and execution of complex and advanced projects related to system and technical product
development. Typically supports multiple project activities and may support multiple programs within the organization. Provides technical guidance
and mentoring to lower level technical ...
everything RF Adds New Web Page for the SATCOM Industry
everything RF has introduced a new technology hub for the SATCOM Sector. This is a single page on the site which summarizes all activity that takes
place in this industry. News, White Papers, New Products and more. Two new categories for the SATCOM Industry have been added to everything
RF - Block Up Converters (BUC) and Low Noise Blocks (LNBs). Products from the leading manufacturers in each of these
categories have been listed and users can find products here based on specification - Frequency
Radio a la Cortlandt Street!
York City has forever, it seems, been the place to be for street vending. A famously large pedestrian populace creates an ideal venue for hacking
goods of all sorts to passers-by. A phenomenon in radio was created in the early 1930s with the rapid advances in technology and high volume
manufacturing techniques, coupled with increasingly efficient transportation of goods on interconnecting roadways and delivery trucks. The photos
included in this Radio-Craft magazine story illustrate the level of enthusiasm by the public for radio. A plethora of
replacement components for repairing malfunctioning
sets and for scratch-built sets at fantastically low prices helped fuel the fire. An offer of 'aluminum chassis' with pre-punched and drilled
holes was really surprising not because of the holes, but for
Focus on Growth Markets Generates Strong Year-End Results for Rohde & Schwarz
Rohde & Schwarz has successfully closed fiscal
year 2014/2015. Order income was 6.1 percent higher than in the previous year, with revenue up 4.1 percent. With its advanced technologies and
trailblazing products, the electronics group was able to maintain its leading market position. Business development focused on test and measurement
and secure communications. In addition, the group substantially expanded its cybersecurity activities.
Google's Balloons to Provide Internet to Rural Indonesia
"Starting next year, three mobile network
operators in Indonesia will begin testing Google's Project Loon balloon powered Internet. Over the next few years, Google said that it hopes that Loon will help put LTE based internet connections within
reach of more than 100 million Indonesians. In Indonesia today, only about 1 out of every 3 people are connected to the web, and most of their
connections are often slow. Many people live in areas without existing Internet infrastructure; on an archipelago
Radio set Prints Newspaper!
Writing about 'outdated' methods of radio-based facsimile machine implementation
in 1934 seems a bit incredible considering how relatively new both technologies were at the time. Nevertheless, Radio-Craft editor Hugo Gernsback
reported on the new era of fax machines
that were on display at the 1933 World's Fair in Chicago. Of course fax machines of that time were not exactly desktop models that could be
located in a corner of your office or cubicle (not that cubicles were common). If you substitute transistors for vacuum tubes, stepper motors
for simple DC motors and solenoids, and solid state lasers and LEDs for incandescent light sources, the fundamentals have not
Bell Telephone Laboratories Ad
of the cavity magnetron during World
War II helped change the destiny of Allied forces as high frequency radar with enough power to detect distant targets while being out of
the easy detection bands of Axis forces' receivers. It was considered a top-level secret with great concern that the technology not fall into
the hands of German and Japanese scientists. According to this early post-war advertisement in Radio News, Bell Labs was totally consumed
by the development of magnetrons, and was relieved to finally be able to boast of its critical role now that the war
Radar & Radio Engineering Crossword Puzzle
It's confession time.
While it is true that all of the RF Cafe crossword puzzles
contain only words, abbreviations, and phrases that pertain to topics in engineering, radar, radio, science, mathematics, astronomy, chemistry,
etc., the actual title of the puzzle is made up mainly to look attractive to search engines. There are puzzles, however, with titles like "Famous Scientists" where I do go through and specifically
fit in names of people like DeForest, Einstein, Edison, Bell, et al. This crossword falls into the former category
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
All trademarks, copyrights, patents, and other rights of ownership to images and text used
on the RF Cafe website are hereby acknowledged.