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.
Please Thank Amplical for
Helping to Deliver
RF Cafe
Amplical
focuses on premium quality
amplifiers and attenuators
at affordable prices. Amplifiers are tuned for exceptional amplitude
flatness and our attenuators are designed for precision and the
utmost in accuracy. Their products are typically available from
stock. It is their pleasure and honor to provide you with both an
exceptional product and exceptional service. Amplical features GaAs
technology.
Merry Christmas 2012!
Never
one to worry about being un-PC, I want to wish everyone who
celebrates
Christmas a very
Merry
one, and a Happy &
Prosperous
New Year
to All, regardless of your beliefs! These are a few of my favorite
Christmas videos. Enjoy.
Pat Nelson: Ace of Test Pilots
(as seen in A Christmas Story)
Do
you remember the scene in A Christmas Story where the kids
Ralphie's the classroom all wear fake teeth and the teacher, Mrs.
Shields, collects them and tosses them in her desk drawer? That
drawer is filled with many formerly confiscated items, including
a copy of "Pat
Nelson: Ace of Test Pilots" (copyright
1937). The story is about a daring young pilot who is regarded
by his peers as one of the best test pilots and racing pilots in
the country. Pat's life is one of tragedy and victory. His father
was killed during a robbery that also left his youngest brother,
'The Kid,' paralyzed from a bullet wound, and his other brother
missing after being absconded by the gang of thugs. The book appeals
to me from many aspects. As my
AirplanesAndRockets.com
website attests to, I have been a lifelong lover of aircraft of
all types. As my
RFCafe.com website attests to, I have been a lifelong lover
of electronics of all types. The Kid, happens to be an "expert radio
Ham" (license number W-103) who is
constantly in contact with Pat when he's in the air. He
(The Kid) was "a true member of that
great clan of radio amateurs who never leave their post when danger
threatens"
...
An Inexpensive
Impedance Bridge
Here
is an amazingly detailed article on how to construct and operate
a near-lab-quality
impedance bridge out of relatively inexpensive components. A
bridge is used to determine the precise value of a resistor, capacitor,
or inductor. Prior to modern, easily affordable digital impedance
meters, both amateurs and professionals relied on such devices for
lab and field work. Why might you need to measure the value of a
component when most are marked with a value? One common application
is when a variable version of a component (or components) is soldered
into the circuit while tweaking for optimal performance, and then
the variable is replaced either with a single fixed component or
a fixed component with a smaller-range variable component (the latter
provides adjustment, but over a smaller range of values). It is
not uncommon when doing the initial tuning on a complete home-built
transceiver to have many variable components in place initially,
and then solder in fixed versions later...
MegaPhase End-of-the-World
Savings Alert - Time Is Short!
MegaPhase’s
2012 "End of the World" Savings! For orders placed by 12/21/12
receive 15% discount off all GrooveTube® cables, 10% off all RF
cables, 5% off all Accessories (torque wrenches, torque screwdrivers,
adapters). Equip your labs for 2013 NOW with MegaPhase’s T&M
and System product line. Lock in your 15%, 10%, 5% discounts
MAYANEND by December 21, 2012.
Pasternack Introduces
New VNA Cal Kits
Pasternack
introduces their new lines of vector network analyzer calibration
kits. The new
vector network analyzer (VNA) calibration kits from Pasternack
provide the RF components needed to enable stable and accurate error
corrected measurements of DUTs using a VNA from DC to 26.5 GHz in
one convenient kit. Calibration of a DUT using Pasternack’s kit
allows for precise measurements needed to meet IEEE 287 standards.
Pasternack’s VNA calibration kits offer broad VNA coverage for the
most popular models including Agilent®, Anritsu®, Rohde & Schwarz®
and other VNAs.
Free e-Book -Doing Innovation:
Creating
Economic Value
The
first eBook in IEEE-USA's Innovation Series,
Doing Innovation: Creating Economic Value – Book 1: Perspectives
on Innovation, was written by Gerard H. (Gus) Gaynor, Retired 3M
Director of Engineering. The Doing Innovation: Creating Economic
Value series was written out of the author’s concern that "while
innovation appears to receive considerable attention in the academic
and business media, these so-called innovations provide little,
if any, consistent and significant economic growth."
PartSim Online Analog
Circuit Simulator
Simulation
Program with Integrated Circuit Emphasis (SPICE)
has been around since 1973. The basic computational engine has always
been open source. It began as a simple analog circuit simulator
that took a structured text file as the input net list and provided
a text file output that contained the calculated values that the
user specified such as DC bias points, transient analysis, and AC
analysis. Component models started with relatively simple definitions.
If you wanted a graph of the response, it was in the form of text
characters with a standard 80-column division on the y-axis and
the x-axis was as many divisions as it needed to be to cover all
the points calculated (often printed out on fan-fold paper in a
pin printer). Yes, I personally used those versions in the mid 1980s.
As time progressed, improvements were added to the computational
engine to handle a wider range of component models including digital
and RF/microwave. More parameters were added to component models
to yield a better agreement between simulation and laboratory measurements.
Lagging...
Mayan Apocalypse
7-Day Weather Forecast
RF Cafe visitor Bob D. sent me this
Mayan
Apocalypse Weather Forecast graphic. Is this great or what?
Note that there is nothing for Saturday, the day after the world
ends. Don't forget to ask your doomsdayer friends to assign you
all their worldly goods today since they won't be needing anything
after tomorrow. Please consider RF Cafe as a beneficiary in your
end-of-the-world planning (send to
rfcafe@yahoo.com via
PayPal).
December Magazine Articles
The engineering magazines have posted their December issue articles
online now. Here are a few you might be interested in reading.
•
Understand Uncertainty for Better Test Accuracy, by Antonio
Castro
•
Ultra Low Noise Amplifiers Improve Cell Coverage and Reduce Costs,
by Paul Mattheijssen
•
A 5G Wireless Communications Vision, by Gerhard Fettweis
Notable Quote
"If
the Mayans were so good at predicting the future, why aren't the
Mayan cites still around?"- Anon (nor
did they predict the coming of Spanish conquistadores - KRB)
Skyworks Launches High
Linearity, Low Power
Amplifier
Skyworks
introduces a highly efficient, broadband, 13 dB gain, GaAs
HBT drive amplifier in a small 2 x 2 millimeter quad flat, no lead
package. The
SKY67130-396LF draws less than 23 mA at 3.3 V, while
achieving +39 dBm OIP3, providing the market with a very compelling,
high linearity solution. On-die active bias design ensures
consistent performance and unconditional stability.
A Few Year-End Job Hunting
Tips from the
IEEE
•
2012 Holiday Networking for Both Candidates and Hiring Managers
to Jumpstart Your Career in 2013
•
Nuclear Engineering: $99,920 median salary
In the Field with International
Pacific
Highway (IPH) Crew
It
is hard to imagine a time when there wasn't a vast network of highways
connecting not just the interior of the continental U.S., but also
interconnecting all of the countries in North America. Just as pioneers
in covered wagons and on horseback forged the routes that became
the Oregon Trail in the early 19th century, so did teams of explorers,
cartographers and engineers do the heavy lifting in the early 20th
century in establishing the first defined roads for expediting the
transportation of goods and persons all up and down the continent's
west coast. Radio operators were among the crews of the
International Pacific Highway (IPH) project. Heavy, bulky, and
fragile tube-based radio equipment was transported in vehicles equally
bereft of adequate facilities in the form of power and shock absorbing
suspensions. This story from a 1931 edition of the ARRL's QST magazine
tells of harrowing experiences in the jungles and mountains of South
America, including...
Selecting the Best Resistor
Technology for
the Application
Vishay
engineering director Yuval Hernik has a brief primer posted
on EDN discussing considerations when selecting resistors for your
design.
Resistors seem like - and are - the simplest of electronics
elements (other than wires), but a thoughtless selection could spell
doom as surely as the wrong
transistor or transformer. Aside from special properties that
must be accounted for in high frequency circuits (stray reactance,
composition), there are 'design centering' needs to account for
tolerances in resistance, temperature coefficient, and mechanical
environment.
Vintage Allen-Bradley
Resistors Advertisement
Allen-Bradley
has been making resistors for a long time. From my earliest days
in electronics in the 1970s, I remember using their products in
hobby projects and then later in professional applications. Rockwell
Automation now owns
Allen-Bradley, so if you want historical information, you will
have to do a search for pages like this one, which shows an advertisement
from the December 1931 edition of the ARRL's QST magazine. According
to Wikipedia: "The company was initially founded as the Compression
Rheostat Company by Dr. Stanton Allen and Lynde Bradley with an
initial investment of $1,000 in 1903. In 1910 the company was renamed
the Allen-Bradley Company."
AWR Blog Online Videos
as Educational Resource
Sherry
Hess, VP of Marketing at AWR, has posted a new blog discussing the
value of online videos as an innovative educational resource for
providing remote learning. The blog, "Kahn
Academy—I’m a Fan!" lauds the
Kahn Academy website,
which provides over 3,500 online videos on all facets of education.
It compares this education model to AWR’s own
AWR.TV online video channel, which
is a valuable resource for customers, university students, and anyone
interested in AWR’s RF/microwave design software.
Pasternack Introduces
New Line of RF Filters
Pasternack
introduces their new lines of
lowpass filters and highpass filters. The new RF filters from
Pasternack are passive components that allow frequency signals to
pass within a certain range and attenuate (reject) frequencies outside
that given range, in this case, up to 3 GHz. Both the new lowpass
and highpass filters are constructed using the Combline design,
which provides outstanding VSWR and long term performance.
Thanks to MECA Electronics
for Continued
Support!
MECA
Electronics manufactures
RF & microwave
components including fixed attenuators, directional & hybrid
couplers, isolators/circulators, power divider/combiners, RF loads,
DC blocks, bias Tees and adapters & cables. MECA has long been
the 'backbone' of high performance wired and air-interfaced networks
such as in-building applications, satellite communications, radar,
radio communications, telemetry applications, mobile radio, aviation &
air traffic communications.
Machinist Calc Pro
Over
on the Design News website,
Jon Titus, former editor of numerous electronics magazines and
all-around electronics whiz, is recommending the Machinist Calc
Pro to people who do a lot of metal machining and woodworking projects.
It performs a lot of commonly needed functions like bolt hole patterns,
thread tapping tables, spindle feed and speed, etc.
Amazon has it on sale now for $70, and if you buy before then
end of the year, you can get an additional
$20
rebate from the manufacturer.
Thanks to Pasternack for
Continued Support!
Pasternack
is a global supplier of
RF, microwave
and fiber optic components supported by a growing list of international
distributors who service customers in more than 30 countries worldwide
and partner with us in pursuit of our vision to be the world’s most
recognized and trusted provider of urgently needed RF, microwave
and fiber optic components and assemblies.
Free Technical Magazine
Subscriptions
Many of the engineering and science magazines offer
free subscriptions
to qualified people. Their advertisers foot the bill. Here are a
few select examples, but there are many others available for just
about every interest.
Lightwave
- Optical communications technology, applications, and industry
trend information.
Asia
Electronics Industry -Reports on the latest parts and components,
material, production equipment and test & measuring instrument.
NASA
Tech Briefs - Reports of innovations developed by NASA and its industry
partners/contractors that can be applied to develop new/improved
products and solve engineering or manufacturing problems
Science Theme
Crossword for 12/16/2012
For
the sake of avid cruciverbalists, each week I create a new
crossword
puzzle that has a theme related to engineering, mathematics,
chemistry, physics, and other technical words. You will never be
asked the name of a movie star unless he/she was involved in a technical
endeavor (e.g., Hedy Lamar).
Free e-Book - Doing Innovation: Creating Economic
Value
Doing
Innovation: Creating Economic Value, by Georgia Stelluto. Excerpt:
"Innovation occupies many pages of the business and academic press,
yet under close scrutiny, it is difficult to find innovation that
provides economic value. Where are the innovations that have an
impact on economic growth? Introducing new features to current products
or processes often dominates discussions on innovation. Much confusion
abounds as to what innovation really involves..."
Anatech Electronics December Newsletter: SAW
Filters
Anatech
Electronics /
AMCrf has posted
their December newsletter. The focus is on SAW filters.
SMA Connector Thumbwheel
Many
people have written over the years asking where to buy those little
donut shaped
thumbwheels for SMA / K (2.9 mm) / V (2.4 mm) RF Connectors
. A lot of companies hand them out at trade shows, with their company
names printed on them. Finding one for sale, though, has been somewhat
elusive. Search no longer. RF Cafe visitor Michael M. just provided
a source for buying them:
Marki Microwave.
Marki's main product line originally consisted of high performance
mixers, but now they also manufacture amplifiers, filters, power
dividers, baluns, couplers, and a host of other RF /
microwave components.
I couldn't find a price on their website, so you will have to call.
Student Freaks Out When Awoken in Physics Class
Watch
this poor guy freak out when his physics professor wakes him while
he naps during class. The lecture was on nuclear physics and atom
bombs.
Pasternack Expands Line of Schottky Diode Detectors
Pasternack
announces the expansion of their line of Schottky diode detectors. RF
detectors from Pasternack are coaxial components that convert the
input RF signal strength into proportional DC voltage at its output,
also referred to as “video out”. The positive-biased Schottky detectors
offer varying operating frequencies ranging from 500 MHz to
26 GHz and are available with SMA connectors. This line of
biased detectors has a RF signal threshold (tangential sensitivity
or TSS) of -54 to -52 dBm.
PMI Intros 0.5 to 18 GHz Switch Bit Attenuator
PMI
Model No.
SAA-500M18G-20DB-SFF is a switch bit attenuator that operates
over the frequency range of 500 MHz to 18 GHz. This model
provides 20 dB of attenuation when a TTL "0" is applied and
less than 3 dB of insertion loss when TTL "1" is applied. This
attenuator switches between states in less than 100 nsec and
maintains a maximum VSWR of 2.0:1 into a 50 ohm impedance.
±5 VDC is required to power. Other frequency ranges and attenuation
values are available.
Caveat for Buying Test Equipment on eBay
While
looking around on eBay for a couple pieces of
test equipment,
I noticed that some of the overseas distributors have products wired
for 220 VAC w/o an option for 120 VAC as used in the U.S.
They do properly state the voltage, but just be careful
because if you are not aware of it, you will need a step-up transformer
or pay shipping to return it. Also, a couple of the ARB products
have software that will not work on a 64-bit Windows system. If
you have any questions, be sure to send a message; they are usually
really good about answering quickly.
PA Design Series: Envelope Tracking Sim and
Analysis
PA
Design Series:
Envelope Tracking Simulation and Analysis, December 13, 1:00
PM ET. Modern modulated signals have high peak-to-average power
ratios (PAPR.) Power amplifiers that must amplify these high PAPR
signals, if using a fixed bias, must be operated at relatively high
output power back off, to avoid greatly distorting the signal when
its envelope excursion is near its peak. This webcast will provide
an overview of Envelope Tracking simulation and analysis.
Many Thanks to Orbel for Long-Time Support!
Orbel
is a precision solutions manufacturer of
photo etched components,
board level shielding, EMI/RFI gasketing, custom metal stampings,
fabric over foam gaskets and plated foils. Orbel's board level shielding
products offer engineers the most flexibility for surface mount
or thru-hole designs.
FITSAT-1 CubeSat Flight
over Erie, Pennsylvania
I
stayed up late last night (early this morning, actually) to watch
the
FITSAT-1 CubeSat satellite flash its Morse code "HI DE NIWAKA
JAPAN" message via super-bright LEDs over eastern North America.
It was scheduled to pass just south of my location in Erie, Pennsylvania,
at 1:14 AM, with a lights-on intensity great enough to be easily
seen with binoculars. FITSAT-1 is a project conceived of and built
by professors and students at the Fukuoka Institute of Technology
(FIT) in Japan. In addition to the LED visual display, the satellite
also carries several Amateur Radio payloads including a CW beacon
on 437.250 MHz, a telemetry beacon on 437.445 MHz and
a high-speed data downlink on 5,840.0 MHz. The CubeSat Project
was developed by California Polytechnic State University and Stanford
University's Space Systems Development Lab. It creates launch opportunities
for universities previously unable to access space. A CubeSat...
Longest English Word Takes
213 Minutes to
Pronunciate
Just
as technologies continually advances with more and more complexity,
so, apparently, do words. I remember as a kid back in the late 1960s
when the word 'antidisestablishmentarianism' was all the rage. It
was pronounced and joked about on all the Prime Time and Late Night
variety shows like Carol Burnett , Sonny & Cher, Dean Martin,
and Johnny Carson. Those 28 letters and 12 syllables pale in comparison
to the new king of the word-length hill. Sporting 189,819 letters,
the long version of a giant protein called
Titin takes the guy in the embedded video 213 minutes to pronounce.
Here is the word in all its glory:
'Methionylalanylthreonyl...
…+
189,777 more letters +…
...prolylprolylleucine'
Skyworks Intros High Power
Switches for
Base Stations
Skyworks
is pleased to unveil three high power SPDT switches for multiple
applications. The
SKY12207-478LF (0.9-4.0 GHz; 50 W),
SKY12208-306LF (0.02-2.7 GHz; 50 W) and
SKY12210-478LF (0.9-4.0 GHz; 100 W) deliver transmit/receive
and failsafe switching functionality for TD-SCDMA and TD-LTE base
stations, as well as land mobile radios and military communication
systems. These PIN diode switches handle continuous wave RF
input power and provide very low insertion loss in the antenna-to-Rx
mode, minimizing the effect on receiver noise figure.
RFMD Intros Absorptive
High-Isolation SPDT
Switch
The
RFSW6124 is an SPDT RF switch featuring a symmetric design for
exceptional isolation. Typical applications for this GaAs pHEMT
switch include cellular base stations and other communications systems
requiring high linearity and power-handling capability. The RFSW6124
uses a non-reflective architecture that terminates ports in the
Off state and provides an enable pin for an All-Off state. Control
of the switch is both 3V and 5V positive logic-compatible.
RF Cafe Quiz: Intro to Infrared
and Electro-Optical
Systems
This
quiz is based on the information presented in "Introduction
to Infrared and Electro-Optical Systems," by Ronald G. Driggers
and Melvin H. Friedman. All RF Cafe quizzes would make perfect fodder
for employment interviews for technicians or engineers - particularly
those who are fresh out of school or are relatively new to the work
world. Come to think of it, they would make equally excellent study
material for the same persons who are going to be interviewed for
a job.
Sherlock Ohms: The Case
of the Scalar EM
Waves
Sherlock
Ohms is a regular feature of Design News that presents submissions
from readers about troubleshooting challenges and how they were
solved. This one is utterly amazing and is titled "Mystery
Signals Show Up in Neurological Amplifiers." Have you heard
of
scalar electromagnetic waves and the [in]effectiveness of shielding
on them? I had not. A Google search resulted in a bunch of conspiracy
theory articles referencing Tesla's writings and how the government
was using them for mind and weather control. Does anyone have credible
information on scalar EM waves? Maybe this Sherlock Ohms case should
have been saved for April 1st.
The Making of Young People
Who Will Change
the World
"Creating
Innovators: The Making of Young People Who Will Change the World,"
by Tony Wagner. A childhood of creative play leads to deep-seated
interests, which in adolescence and adulthood blossom into a deeper
purpose for career and life goals. Play, passion, and purpose are
the forces that drive young innovators. Wagner shows how we can
apply this knowledge as educators and what parents can do to
compensate for poor schooling. He takes readers into the most
forward-thinking schools, colleges, and workplaces in the country,
where teachers and employers are developing cultures of innovation
based on collaboration, interdisciplinary problem-solving, and intrinsic
motivation. The result is a timely, provocative, and inspiring manifesto
that will change how we look at our schools and workplaces, and
provide us with a road map for creating the change makers of tomorrow.
Notable Quote
"I
don't care what the majority voted to do, they don't have a right
to steal my money just because they vote for it." -- Peter Schiff,
CEO of Euro Pacific Capital, on CNBC (start
video at 4:40)
Pasternack Needs an
RF/Microwave Copywriter
Pasternack
Enterprises announces the availability of a new position at their
Irvine, California, location.
•
RF/Microwave Copywriter and Content Manager
TriQuint Semiconductor Has
Two New Job Openings
TriQuint
just announced two new fulltime openings at their Hillsboro, Oregon,
location.
•
RF Metrology Engineer
•
RF Substrate/Laminate Technologist
Flying Radiomen
[and women]
of the Ferrying
Division
"Necessity
is the mother of invention" is an oft-heard phrase that never rang
truer than during World War II. Both the Axis and the Allied
powers had extremely brilliant and capable people working to defeat
each other, driving advances in technology and methods at a break-neck
pace for nearly a decade (remember WWII began
before the U.S. entered the fray in 1941). Aircraft and radio
were powerful new weapons for all sides at that point since both
were still in their fledgling modes in WWI. Efficient and effective
execution of aircraft ferrying, troop movement, and supply delivery
was absolutely dependent on radio equipment and operators that could
adapt to new strategic situations and endure all sorts of weather
and geographic stresses. While the Army Signal Corps had a good
cadre of
radio operators available, few were experienced with operating
in their gear while airborne. Background noise
(audible and electronic) and vibration
from the engines and airframe tested the limits of skills...
Amateur Radio Quiz:
Specs or Pepper?
Pondering
a possible purchase puts the potential pocketbook provider in a
pickle! Unless, that is, they are a savvy
savant of
specifications. This quiz will lead you through a jumbled jam of
jargon to see how well you speak the language of the specification!
Science & Engineering Theme
Crossword
for 12/9/2012
For
the sake of avid cruciverbalists, each week I create a new
crossword puzzle that has a theme related to engineering, mathematics,
chemistry, physics, and other technical words. You will never be
asked the name of a movie star unless he/she was involved in a technical
endeavor (e.g., Hedy Lamar).