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.
Bird Technologies, a leading provider of
RF components, subsystems, test equipment, and services, today introduced the
Model 7022 Statistical RF Power Sensor, the only thruline RF power measurement device that provides
the statistical analysis capability required to accurately characterize the RF power characteristics of any digitally-modulated
signal employed in wireless communications systems. Bird's Model 7022
What are the coldest and hottest absolute temperatures possible
according to theory? Answering the 'coldest' part of the question is objective and therefore easy: Absolute zero = 0 K
= -273.15 °C = −459.67 °F. The 'hottest' part of the question, sometimes referred to as 'absolute hot,' is harder.
Most people who deal with such things consider the highest possible temperature to be the Planck temperature = 1.416785(71)x1032 K. A lesser
cited value is the Hagedorn temperature ...
The numbers 5 and 10 were prominent in today's search for career
enhancement articles so I decided to make it this week's theme in regard to the value of advice offered. 5¢ today buys
what 2¢ bought in 1980, per the Bureau of Labor Statistics'
Inflation Calculator, and 10¢ is the equivalent
of 2¢ in 1970. The idiom about "adding my two cents worth" of opinion or advice goes way back to Biblical times, but the
Inflation Calculator ...
-
5 Types of Bosses and How to Deal with Them
-
10 Things We Hate About Bad 'Leaders' <more...>
Philco began
selling radios in 1928 after originally being a storage battery manufacturer. Their first television, the Predicta, was
introduced in 1957. That was more than a decade after Philco Corp.'s James Carmine wrote this article discussing how the
American buying public (aka consumers) might embrace the concept of TVs in their homes. Many
people at the time had no interest in television both due to the expected cost and the relatively poor performance of existing
examples. If you have ever seen pictures of early
...
MECA Electronics' new compact 100 watt
low PIM terminations feature industry
leading PIM performance of -160 to -165 dBc, typ., all while handling full rated power to +85°C. All of the terminations
cover 0.698 – 2.700 GHz frequency bands in 7/16 DIN, Type N, and 4.1/9.5 (mini-DIN) connectors, VSWR = 1.10:1 typical /
1.20:1 minimum. All in a compact package of 8.5" x 3.0".
Electronic
Troubleshooting, 2014, by Daniel Tomal, Aram Agajanian. The Most Complete, Current Guide to Troubleshooting and Repairing
Electrical and Electronic Devices. "If it's electronic, and there is troubleshooting to be done, then this is the book to
reach for!" - Dr. Simon Monk. Fully updated for the latest technologies, devices, test instruments, and problem-solving
methods, the new edition of this practical resource provides you with the comprehensive information you need to troubleshoot
today's electrical and electronic equipment. Inside you'll find new and enhanced coverage of: Wireless communications, Embedded
microprocessor systems ,Cutting-edge medical diagnostic equipment ,Advanced networking technologies. The book uniquely blends
traditional electrical theory and components with modern networking and electronic technology
...
You have heard of the pumped laser and maser. Here is a new type of
pumped energy system: the vaser. 'Laser' is an acronym for 'light amplification by
stimulated emission of radiation,' and 'maser' is an acronym for 'microwave
amplification by stimulated emission of radiation.'
I coined the term 'vaser' after reading an article in the June 2014 edition of Model Aviation about a relatively
new form of radio controlled model sailplane sport -
dynamic
soaring - that, using a specially developed technique to exploit geography and prevailing winds, produces aircraft speeds
of more than 400 miles per hour. Per my definition...
This article by
Joshua Fruchter,
writing for
IMS ExpertServices, tells a tale of an unexpected action by a judge that, based on his own understanding
of regression analysis, disqualified the works of a hired mathematical 'expert' apparently because of multiple
errors and omissions in the calculations. The defendant is one you will recognize from their publication of technical books
and college textbooks: McGraw-Hill (Construction). Mr. Frutcher
has been publishing a lot of great articles lately that RF Cafe visitors would find interesting; I'll be posting another
by him soon.
Werbel Microwave introduces its new product line
of Bias Tees with two models 1BA300 and 1BA600, respectively, covering 380 MHz to 6 GHz. These units come standard
with SMA-Female connectors in a housing measuring 1.25" square by 0.75" deep. VSWR is 1.3:1 or better at RF ports, minimum
isolation is -25 dB, and insertion loss is 0.6 dB, max. DC terminal rated at 50 VWDC, 200 mA max.
"The key to being a good manager is keeping the people who hate you
away from those who are still undecided." Casey Stengel, Major League Baseball manager.
Most of us here in America recognize the
Packard
Bell name from the line of personal computers they sold in the 1980s and 1990s. I owned three of them, beginning with
an Intel 80286 model, then an 80486, and finally a Pentium model. They were in the 'pizza box' format that sat on the desk
with the CRT monitor on top; I always preferred that configuration over the tower type. Before Packard Bell made personal
computers, they made personal radios for the desktop beginning back in the 1930s. That
...
Wall charts featuring
high tech themes are Art du Jour for engineering labs, cubicles, and offices. Many companies provide custom designs that
provide useful information about subjects like RF and microwave system design, frequency standards, radar fundamentals,
wireless network planning, regulatory topics, etc., while also often taking the opportunity to promote their products. Unlike
the lab wall posters of yore, today's
posters are large and full of vibrant colors. Since it had
...
Anatech Electronics offers the industry's largest
portfolio of high-performance standard and customized 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 SAW filter designs, one is a duplexer covering the 746-756 MHz / 777-787 MHz
LTE band, another is a 1575 MHz BPF for GPS, and the last is an 813/858 MHz PTT duplexer.
This is the third and final installment of a series on
iron core transformer and reactor design. You of course are familiar with transformers, but what about
reactors? A reactor is an inductive element used to limit overvoltage or short circuit current from a source to a load.
These days they are most often seen in electrical distribution substations, associated with transformers. After the tease
implying that you will learn something
...
This week's engineering crossword puzzle contains many
filter-related words. For the last
couple crosswords, I have been trying to integrate some theme to make working it a little more interesting. Last week, for
example, I did an Amateur Radio theme
crossword puzzle. It takes a little to do because forcing words into specific squares makes it harder for the software
to fill the empty ones.
Sunspot cycles repeat approximately every 11 years,
so there had only been six solar maximums from the beginning of
long distance
radio communications (Marconi in 1901) up until this article was published in 1957. That
year had the sun experiencing an extremely high number of sunspots, as had the previous few years, which caused communications
to be profoundly affected during the period. Under ideal conditions, high energy electrons typically ejected from the sun
(CME) cause the Earth's ionosphere to become
...
While
you're waiting for the clock to chime 5:00 so you can get started on the weekend, here are a few more career advice articles
to peruse. Worst case, you can look Monday morning as the realization of a new work week hits you :0)
-
I've Interviewed 100s of Candidates and the
Ones I Hire Always Do This
-
4 Steps for Improving Your Design Engineering
Career
-
How to Explain Your Fabulous Unemployment
Stint
-
Is Your Cover Letter Killing Your Efforts?
-
15 Websites
to Jump Start Your Career
OK, some people might get a bit upset, but after
just reading a news story about an Ebola scare on a
U.S. Airways flight, I had an epiphany about what this year's top Halloween costume might be: a mock
HAZMAT suit! You can get them cheap on
Amazon. The gov'ment keeps telling us we have nothing to worry about because, "We've got this." In the
rare case that the 'experts' are wrong, your kid will have a functional suit to wear to school where respiratory bugs are
already attacking students. Happy Friday!
Rohde &
Schwarz is now selling the ARTS turnkey radar target simulator from ITS and miro-sys. When combined with the R&S FSW
high-end signal and spectrum analyzer and its analysis option for FM CW chirp signals, the ARTS constitutes an innovative
test solution for the development and production of automotive radar sensors, automatically performing realtime characterization
of the chirp signals typical of automotive radar
Here is the latest
RF Cafe Quiz based on the new book by Zhancang Wang titled
Envelope Tracking Power
Amplifiers for Wireless Communications. I am continually amazed at the brilliance of people who work tirelessly
to advance the state of the art of technology, medicine, transportation, and many other areas. They manage to succeed in
spite of myriad obstacles placed in their collective way by infuriating levels of government regulation and government-imposed
societal manipulation. Scanning through the many engineering
books I receive from Artech House, Cambridge University Press, et al, is truly
...
Here is another group of Radio
Service Data Sheets from late 1930s editions of Radio Craft. As explained before, I know most regular RF Cafe visitors
are not interested, but I need to post them on the homepage so that the major search engines will find and register them
quickly. Everything that appears on the homepage can be found in a Google search within about 8 to 12 hours - pretty amazing. •
Crosley Fiver Chassis "Chairside" Model 567 •
Belmont Model 408 Battery "Farm" •
International Kadette Model 1019 A.C. Superhet •
Stewart-Warner Models 97-561 to 97-569 (Superhet Chassis 97-56).
Triboelectric
charging is the phenomenon whereby adhesion forces between two surfaces causes the dislodging of electrons from nearby
atoms, with those electrons being attracted to the material with the highest positive potential as the interface attempts
to neutralize itself. Relative contact motion is most often the cause of triboelectric charge transfer, but simply pulling
apart two dissimilar surfaces can also be the mechanism for charge transfer. Electrostatic discharge, a manifestation of
triboelectric charging
...
Pasternack, an industry-leading manufacturer
and supplier of RF, microwave and millimeter wave products, announces the release of eight new
high power
linear amplifiers that provide accurate signal amplification across a multitude of commercial and defense applications
such as communications, radar and sensors, test instrumentation, telecom infrastructure, fixed microwave backhaul, commercial
two-way radio, and many others. These GaAs PHEMT MMIC-based amplifiers operate from 0.8 GHz to 9.5 GHz and
We
don't hear much - if any - talk these days about a certain weapon type being a 'peace maker,' 'game changer,' or a 'stale
mate proposition.' That is because most nations, or for that matter terrorist groups, have access to some ferocious weapons.
The world has operated for a long time on the
Mutually Assured
Destruction (MAD) principle, where skirmishes have been fairly local. Many conspiratorialists as well as arguably rational
people believe the real game at hand is Mutually Assured Financial Destruction, where world financial powers cooperatively
trade off monetary wins and losses
...
M/A-COM, a leading supplier of high performance RF, microwave,
and millimeter wave products, today announced at EuMW 2014 in Rome, Italy, its
MAMX-011023 low noise active mixer
is available for sampling immediately. The highly anticipated market arrival of the 4–23 GHz MAMX-011023 discrete mixer
gives system designers unrivaled flexibility to target a wide range of applications with a single mixer component. Offering
the widest frequency bandwidth coverage
Here are a four more comics from magazines of the days of
yore. Evidently Radio Craft readers would submit ideas for funnies and then artist Frank Beaven would draw the
comics. I particularly like the one with the radio aerial stretched between the two teepees. It is rare to find a comic
in a technical or hobby magazine these days. I don't know why that is. Enjoy.
A Practical Design
of Lumped, Semi-Lumped & Microwave Cavity Filters, by Dhanasekharan Natarajan. This book presents the application
of microwave literature for designing lumped/semi-lumped filters and combline/iris-coupled microwave cavity filters. It
provides the physical understanding of the terms and characteristics of radio frequency (RF) filters. The book complements
engineering text books on RF components and provides support for the project assignments of students. In addition to the
functional design of RF filters, the integrated design approach for producibility and...
As reported in the October 2014 edition of Inc.
magazine, all the government agency, movie producer, school system, news media, advocacy group, and many other entities',
promotions of woman-owned businesses has evidently paid off according to a major study on the
success and failure of startup firms within
their first five years of operation. I cannot, out of respect for the copyright, reprint the detailed colorful chart that
appears in print, but a thumbnail of it is offered here for reference. Five primary topics were investigated
...
Is there such as thing as too many articles on
transmission lines?
I think not, at least for most visitors to RF Cafe. Since the fundamentals of transmission lines have not changed in the
last century, it really doesn't matter when an article was written. This one covers the basics of impedance and wavelength,
and then delves briefly into the subjects of antenna feeder transmission lines and using transmission lines as impedance
transformers. As with most topics these days, there are many software programs available that will calculate parameters
for you, but successful ...
RF & Microwave Articles of the Week
Lots of good articles have been published recently. These are just a
small sample of them.
-
European RF Defence Sensors Systems
Challenges and Innovation, I. Montiel-Sanchez
-
Balun Basics Primer:
A Tutorial (p22), D. Jorgesen
& C. Marki
-
Receiver
Design Considerations in Digital
Beamforming
Phased Arrays, P. Delos
-
Maximizing RF Spectrum Utilization with
Simultaneous Transmit and Receive,
C. Cox III & E. Ackerman
- Missing Datasheet Details Can Cause Problems
G. Chenier
-
Envelope Tracking Comes of Age on Mobile
Handsets, K. Nickerson
Electronic counter-warfare has been around nearly as long as
electronic warfare
itself. Controlling what a population hears on its radios is a fairly simple process since overwhelming a commercial broadcast
station signal requires only a more powerful transmitter. It was commonplace during wartime for an invading force to set
up high power stations in population centers to block signals meant to inform people of aggressor activity, or even to play
music. Often, not only was the possession of a personal radio verboten, but even getting caught listening to one could spell
real trouble. However, as with booze during Prohibition, the mere fact that something
...
"The whole aim of practical politics is
to keep the populace alarmed (and hence clamorous to be led to safety) by an endless series of hobgoblins, most of them
imaginary." - H. L. Mencken, In Defense of Women. Does that remind you of any current 'hot button' tech topics ... like AGW?
Reporting to NuWave Engineering's Director
of Business Development, the
Business Development Representative has the challenging task of identifying business opportunities for
the organization, cultivating key client relationships, performing business capture planning, management, and execution
and ultimately delivering bookings for the company's design services, engineering services and products. The ideal candidate
will have a bachelor's degree in electrical engineering (or equivalent), with a successful
business development track record
The new R&S ZVAX-TRM from Rohde & Schwarz will have
its debut at this year's European Microwave Week. It is an extension unit for the high end network analyzers from the Rohde &
Schwarz R&S ZVA family. The R&S ZVAX-TRM can be combined with an R&S ZVA to yield a powerful, compact and highly
customizable system. The R&S ZVAX-TRM conditions the signals from the network analyzer as required for a given task
and either returns them
A century from now somebody will re-publish a story about
the first human voyage to the planet Mars, and many of the folks reading it - or at least its headline - will deem such
information obsolete and not worthy of his/her/its time reading. The same is true for many of these historical articles
I post here on RF Cafe for the benefit of those people who appreciate the efforts and sacrifices of men and women who came
before us to push back the frontiers of ignorance.
Howard Hughes,
whose name is familiar to fewer and fewer people these days, was a well-known and,
...
Is it just me, or does
there seem to you, too, to be a flood of career
advice stories lately? Just about every website and magazine I read has above-the-fold headlines for job hunters and
people trying to get ahead in their present positions. A lot of it is old advice presented in a new wrapper, but as with
an article on basic ...
-
How to Win at Office Politics Every. Damn. Time.
-
Why Successful People Never Bring Smartphones
to Meetings
-
The 5 Deadliest Career Mistakes <more>
This week's crossword puzzle has an
amateur radio theme, with many of
the words being related to that subject. All the rest of the words are technical in nature, so you will not find names of
remote mountain peaks or of Hollyweird movie stars. Enjoy!
Advanced Test Equipment Corp. has in immediate
need for a
Repair Lab Technician to, among other 
duties,
calibrate, troubleshoot and 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
Mesuro with support from National Instruments announces its latest advance in the
utilization of PXI to improve the speed of test for today's technical demands…At European Microwave Week in Rome, 7-9th
October, the two organizations will demonstrate a load pull set up that uses a traditional passive tuner for fundamental
tuning and adds the RAPID PXI
digital tuner to provide a high speed harmonic tuning capability.
NI AWR Design Environment is a portfolio
of software products that RF/microwave designers can use to design,
develop, and realize rnicrowave/Hf components, circuits, and systems, including MMICs, RF PCBs, microwave modules, RFICs,
communication systems, radar systems, and antennas These software solutions streamline the engineering design process from
concept through to simulation and to final physical implementation.
Hmmmm.... at
the time I marked this stereo preamp project for posting I must have had a really good reason for it, but now I can't recall
what that really good reason was. Maybe it was simply to mark the point in time when
stereophonic electronic equipment was just beginning to be mainstream. Oh well, somebody somewhere will
do a Google search on the topic someday and will be elated to find this. Thanks for your indulgence.
Back in April I posted a review of Dr. Francesco Fornetti's book
and online training course titled "Conquer Radio Frequency,"
for which I created a 10-question RF Cafe
Quiz. "This material, which includes a full-color textbook and over 12 hours of video tutorials, provides a comprehensive
guide for the RF and Microwave engineering student or junior professional. Dr. Fornetti has generously offered a free
6-month subscription to a winner of the monthly RF Cafe
Book Drawing.
Oculii is an
advanced radar sensor
developer specializing in 3D radar design and fusion. 3D sensors have traditionally been the domain of high power, expensive
military grade radar or laser systems. Backed by top-tier Silicon Valley angel investors and VCs - we've turned this paradigm
on its head, leveraging advanced sensor fusion techniques to manufacture smarter, high precision sensors and systems. Our
technology allows us to extract unprecedented accuracy, range, and 3D positioning information
It took me a couple passes of the explanation to comprehend
the advantage of a Thomson-Varley (aka Kelvin-Varley, since Thomson and Lord Kelvin are one and the
same person) switchable voltage divider compared to a standard type. At first I thought the author, Edwin Bohr, was
implying that the source and load impedances would not have as great of an effect on the accuracy of the divider
(and to some extent it is less sensitive), but the main advantage is that the configuration
permits simple cascading stages of decade dividers to achieve essentially any degree of resolution. Both a standard series-wired
type voltage divider and ...
Brian W., of Sandviken, Sweden, also a
September Book Drawing winner, wisely chose
Printed MIMO Antenna Engineering as his prize. Artech House generously provided this book as well. I pay the shipping costs to winners. Most months
I send notices to two people, and most months neither responds within a few days, so I select one or two other people to
give a chance to claim a free, recently published book valued at over $100. Some months I get no responses at all after
4 or 5 notices.
Here is this week's collection of
career-related articles and news tidbits that seem
useful. Admittedly, I have not read every word of every item, but those selected pass the quick scan test. I try to vet
them to filter out stuff that applies mostly to people seeking jobs as accountants or clothing store managers. There seems
to be a lot of intern news lately. If you or someone you know are/is considering interning,
The Savvy Intern seems like a good website to monitor.
-
Switzerland Tops List of Countries Where Salary Expectations Are the Highest
-
How to Build a Winning Relationship with Your Boss
-
6 Questions to Ask Before You Quit Your Job to Start a Company
-
Sample Communication
Phrases for Performance Appraisal <more>
Chances are when you think about
high power
RF frequency sources, it pertains to transmitters for analog or digital data, or maybe for imaging applications like
x-ray machines. There is, however, another very large industry that uses high frequency electromagnetic energy for heating
of materials in product processing. Frequencies range from tens of kilohertz to tens of megahertz, with power levels into
the megawatt realm. This article from a 1945 edition of Radio Craft points out a few applications used in the day, and now
there are many more areas where high power RF is used. Adhesive
...
Hands-On Introduction to LabVIEW for Scientists and
Engineers, by John Essick. This book provides a "learn-by-doing" approach to acquiring the computer-based skills
used in daily experimental work in engineering and the sciences. Ideal as an instructional lab textbook or for self-study
by individual researchers, this book is not a manual-like presentation of LabVIEW, but rather leads its readers to mastery
of this powerful tool through
...
Craig P., of Seattle, Washington, is
a winner in the monthly RF Cafe Book Drawing; he wisely
chose
Frequency-Agile Antennas for Wireless Communications. Each month I select one or two people
who have either purchased my software or who have written to me about an issue on RF Cafe. Many of the books are used as
the basis for my RF Cafe quizzes, and have been graciously donated by,
in this case, Artech House.
M/A-COM Technology
Solutions Inc. ("MACOM"), a leading supplier of high performance RF, microwave, and millimeter wave products, today announced
a new portfolio of surface mount S-Band GaN power products optimized
for commercial air traffic control, weather radar and military radar applications. The new products are available in a range
of packaging options and power levels. The 30 Wpk and 85 Wpk Hybrid GaN Amplifiers are complemented by a 350 Wpk
But nine times out of ten when you draw
a blank in analytic geometry or calculus, you'll find that your trouble is caused by weakness in algebraic manipulation."
That statement is not a major factor of the plot, but it does ring true in a familiar way. I remember noting that the guys
who had trouble in calculus class usually did so because they were weak in basic algebra and trigonometry. An
engineering calculus class moves at such a rapid pace, with many new concepts thrown at you every day,
that you absolutely must not have to learn algebra and trig concurrently
...
Advanced Test Equipment Corp. has in immediate
need for an
RF Calibration Technician to perform calibration and repair of medium to high level test and measurement
equipment. 
The successful candidate will requires little assistance
and supervision on to create calibration data sheets accurately and efficiently with minimal supervision based upon instrument
specifications and approved calibration procedures, identify and recommend products and related peripherals and accessories
to add to our rental inventory