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.
Fellow USAF radar tech
Greg Bucchieri just checked in with his service information.
Greg worked on the one-of-a-kind MPN-17 radar that operated simultaneously on two separate S-band search frequencies in
order to reduce ground clutter in the display. Like the MPN-13/14 that I worked on, it had a vacuum-tube-based transmitter
Thanks Much to PMI
for Renewing Their Support
Planar Monolithics Industries' organization
has been setup to design, develop, manufacture, test, and market complex state-of-the-art hybrid
RF MIC and MMIC components, supercomponents, and subsystems. Unique products
for applications in space, military, commercial, telecommunications, and consumer electronics systems in the DC- 40 GHz
range are their specialty.
PMI Intros 2 to 18 GHz
Low Noise Amplifier
PMI Model No.
is a 2.0 to 18.0 GHz Low Noise Amplifier that has an integrated bias-tee network on the output port. This amplifier
provides 30 dB of gain while maintaining a maximum gain flatness of ±2.0 dB max over the operating frequency.
The noise figure is less than 4dB and offers an OP1dB of +20 dBm minimum and an OIP3 of +30 dBm typical. The amplifier
requires +12 to +15 VDC and the current draw is less than 350 mA.
How to Hire
the Perfect Employee
A picture of human brains is not the
way I normally prefer to illustrate a concept, but in this case it works pretty well. Inc magazine columnist Phil
Libin, who is a co-founder of Evernote, wrote about a common lament of
not just entrepreneurs like himself, but also of big corporation managers -
a tendency to micromanage underlings. The article is only one page long so I won't regurgitate everything
he wrote other than to say that in the end, the solution is to always hire people that can do the required job better than you can do it yourself. That way you are not always
disappointed at performance because you believe you could do the job better yourself if only you had the time. That's great
advice. Look at the full-size picture he uses.
February MPD Articles Online
Product Digest has become my favorite trade magazine because at least for my level of involvement, it seems to have a more
consistent selection of practical application articles. That's not to take away from the others; it's just a personal choice.
Barry Manz'sMilitary Microwave Digest, also the best in class
for its specialty, is an occasional supplement to the monthly mailing of MPD.
It was only a matter of time before someone became a victim of an
assault. A story hit the wires this morning about a firefighter in NYC beating his wife in the head with an iPad. "When
she tried to escape, he grabbed her by the hair, threw her onto a patio floor and locked the door, according to published
reports." So, we have a hostage taken and extreme physical violence, all caused by easy access to a personal electronics
device. No doubt the domestic terrorist had large capacity RAM modules installed. Does anyone really need more than 16 GBytes
of RAM for sport computing? Only someone with an intent on doing personal harm would need the newest large capacity 128
GByte model. Do iPads imbue owners with a sense of superiority and invincibility who feel powerful when in possession of
one? What about iPhones, which are easier to conceal? Why do citizens even
need iPads when the Constitution was written and shared with pen and paper? Lawmakers should immediately introduce legislation
to ban RAM modules of more than 16 GBytes for iPads and iPhones. Only law enforcement and the military
McWatts Comic Strip
McWatts was an electronics-themed comic that
appeared in Popular Electronics back in the late 1957s. Artist Carl Kohler's main character is a stereotypical Joe Sixpack
electronics hobbyist who always dreams up unique way to deal with situations. This edition shows
way of keeping the kids from using his prized tools as toys. I was always leaving my poor father's tools laying around the
house and too often in the yard where they would get rained on and start to rust. If I were him, I would have been harder
on me for repeat offenses.
Antenna Tuning Solutions
Skyworks Solutions is ramping several antenna tuning products with
leading smartphone manufacturers. Skyworks' devices are meeting the market demand for tunable antennas which dramatically
improve performance by increasing data throughput, reducing dropped calls and minimizing the antenna footprint needed for
today's multiband LTE smartphones. Antenna tuning and antenna diversity are both key elements to solving these challenges.
Antenna tuning enhances cellular operators' available spectrum while antenna diversity is an effective means for improving
RF transmission performance.
Thanks to Innovative Power
Products (IPP) for Support!
IPP has been designing and manufacturing
RF passive components for more than 25 years for all aspects of commercial
and military applications. Their couplers, combiners, RF resistors, and terminations incorporate the latest technology in
materials available, which equates to unrivaled product performance. An ISO-registered quality system assures customers
of a reliable supply of components for their applications. Contact a design engineer today for special requirements.
Why Key Clicks?
Waveform shaping is essential in today's crowded communications spectrum. Spectral
masks are precisely defined in order to prevent "spreading" beyond the allocated frequency ranges at defined power levels.
Whenever anything other than a continuous sinewave is being broadcast, there is spectral content generated in addition to
the fundamental frequency. A Fourier transform of the waveform reveals which frequencies at what power levels comprise the
waveform. The CW (continuous wave) signal used by Morse code operators is a pure sinewave (or nearly so), but there is a
spectral problem with it every time the signal turns on or off because of the square-ish edges involved during switching.
RC networks are used in the transmitter
circuits to tame the edges so that they do not turn on and off so quickly and in doing so reduce the extraneous frequency
content. Author George Grammer argues that even though the signal could theoretically be made 'clickless' (aka "chirpless'),
there is an auditory benefit to the clicks or chirps that aids operators listening to high speed code transmissions.
AWR Sponsors and Exhibits
at EDICON 2013 - Many Papers
AWR is a gold sponsor at the
Electronic Design Innovations Conference ( EDICON) 2013, which
runs from March 12 -14 in Beijing, China. Together with parent company National Instruments, AWR will be showcasing at Booth
#255 joint hardware/software solutions, as well as the first update in 2013 of the AWR Design Environment™, inclusive of
Microwave Office®/Analog Office® circuit design software, Visual System Simulator™ (VSS) system design software, as well
as AXIEM® 3D planar electromagnetic (EM) software and Analyst™ 3D finite element method (FEM) EM software.
Skyworks Captures Initial
SkyOne™ Design Wins
Skyworks Solutions today announced that several leading
OEMs and smartphone providers are leveraging the company's highly customizable, fully optimized
SkyOne™ front-end solution. The
SkyOne™ platform, which integrates all RF and analog content between the transceiver and antenna, reduces complexity, size
and time-to-market for customers with demanding architectures for advanced mobile applications. Utilizing Skyworks' full
technology portfolio and advanced multichip module capabilities including proprietary shielding and packaging, SkyOne™ is
the world's first semiconductor device to condense multiband power amplifiers and high throw switches along with all associated
filtering, duplexing and control functionality into a single, ultra-compact package.
A Passive Audio Amplifier
for Your iPhone or iPad
Locke has taken a low tech approach to making amplifiers for your iPhone and iPad. Rather than build an electronic contraption out of electrical components and speakers
that requires a power source, he 'repurposes' discarded brass musical instruments for the task - ingenuous, I must say. Valves and levers are removed
and a fancy metal cradle is attached to the reed port in a manner that positions the mobile device's speaker directly over
the instrument's air intake. Videos are provided demonstrating the significant amplification afforded by the arrangement.
It's hard to tell whether the full audio range is amplified sufficiently or if only those frequencies within the normal
playing range are affected. Regardless, these functional sculptures would make a great conversation piece or even a gift
for a musician friend.
Foil Those Tube Forgers
Gray market electronic components are not
just a recent problem. Long before IC foundries were set up in China, Indonesia, Vietnam, etc., to produce counterfeit semiconductor
components, there were unscrupulous manufacturers turning out bogus components of all sorts. Marking unauthorized microprocessor
and amplifier packages with an industry-leading brand name and part number is a real problem, but such practices extend
back to the vacuum tube era. This story from a 1957 edition of Popular Electronics tells the story of how companies
like General Electric and Sylvania dealt with the situation.
A Review of Transmission
Lines as Circuit Elements
Mr. Wilfred Jensby wrote
an incredibly detailed article for the November 1966 edition of QST that delves deeply into the subject of using
lines as distributed circuit elements. I did a search on his name, figuring that he likely had other publications of
like sort, but nothing was found. Information contained herein is similar to what you would expect to find in a Master's
level engineering course textbook or in a $100+ technical book from Artech House, Cambridge University Press, John Wiley &
Sons, etc. The brain-zapping equations are omitted with only a great, layman-level discussion of the concepts and some really
nice illustrations and graphs. This is definitely an article you will want to check out and pass on to colleagues.
The Global Innovation
"The Business School for the World," located in France, has just released its 5th annual publication of
Innovation Index 2012. The study analyzes a country's ability to foster invention and innovation. For the second year in a row, Switzerland lead in overall innovation
performance. The U.S. squeaked into last place within the top 10, with even Ireland (no disrespect
meant to the Emerald Isle) squarely whooping us. Canada came in at #12. Of EUR (European)
countries Switzerland leads at #1, the U.S. leads NA (N. America - real difficult) at #10,
Israel tops the NAWA (North Africa-West Asia) region at #17, Singapore (#3) leads SEAO
(South East Asia Outlook), Chile (#39) tops the LCN (Latin America
and the Caribbean) region, and India, #64, rules CSA (Central and Southern Asia). As
usual, I blame the pathetic politicians for utterly destroying the country's ability to create and produce. Their overbearing
regulations, obsession with 'diversity,' social engineering, national self-flagellation, and pandering to leeches is killing
RFMD Expands Leadership
in RF Power Management
RF Micro Devices today announced the addition of multiple new products to RFMD's industry-leading portfolio of
envelope tracking (ET) power management
and power amplifier (PA) solutions. RFMD's ET-based solutions leverage the Company's leadership in RF power management
and cellular PAs to improve system-level efficiency in high-data rate applications. The new RF solutions — the RF7389, RF7390,
RF7459, RF8081, and RF8085 — comprise ET PMICs, ET multimode multi-band (MMMB) PAs, and ET ultra-high efficiency PAs. RFMD's
expanding ET product portfolio is compatible with the leading LTE chipsets and provides full ET compatible coverage of all
FD-LTE and TD-LTE bands.
Analog Devices' ADSimRF v1.7
Analog Devices just announced
the release of the latest version of their ADISimRF applet for calculating cascaded RF component parameters. It takes typical
input values for up to 15 stages and returns typical cascaded values at the output. As I do with any such program, I compared
its results with those of my RF Cascade Workbook (RFCW) spreadsheet. The numbers agree as
expected since both use pretty much the same set of well-established textbook formulas. One difference in the two programs
is that ADISimRF appears to use the standard IP3 (3rd-order intercept point) cascade formula
for calculating P1dB (1 dB compression point), whereas RFCW uses Psat
(saturated power) instead since the P1dB formula is only an approximation of widely varying
nonlinear response and might lead to a false sense of security. RFCW's Psat calculated values simply test what the output
power level for a device would be
Amateur Radio Quiz: Book 'Em!
Ham or not, this amateur radio quiz will provide a nice break from the workaday routine and might even challenge you
a bit. Sez the ARRL: "The great tradition of self-learning and
mutual education is alive and well at the outset of Amateur Radio's second century. The success of that tradition leans
heavily on the books -- and now websites -- of amateurs willing to share their radio know-how with others. This month's
quiz touches on publications from yesterday and today, in honor of the many authors from whom we learn."
E- Discovery: 10 Strategic
Steps for Defensible Search
Every once in a while
I receive an e-mail from someone wanting advice on how to conduct a patent search to determine whether his idea has already
been registered. Many people are sorely disappointed to learn after putting a lot of work into what is truly an original
idea for them only to discover later that a patent has already been issued for the concept. The U.S. Patent and Trademark
Office (USPTO) has some pretty good tools for research (see "How to Conduct a Preliminary U.S. Patent Search"),
but in order to be successful you really need to have a proven, methodical strategy for using those tools. Simply entering
a few keywords rarely - if ever- results in a sufficient effort. Mr. Tino Kyprianou, guest author for IMS ExpertServices,
has written an article titled, "E- Discovery:
10 Strategic Steps for Defensible Search" that provides some advice on how to proceed.
Please visit Dong Jin TI in Appreciation of Their Support
Technology Innovations is a premier manufacturer of RF Connectors,
Cable Assemblies and Components. They are highly recognized as an RF industry leader in Korea. Dong Jin TI's premium
products offer a competitive price, on-time delivery and best quality in the industry with No Minimum Order and One Day
Delivery. Equivalent product suggestions with drawings and speciation available to replace existing items. VSWR reports
available on request.
Science & Engineering
Crossword for Feb. 24, 2013
Every Sunday I create an
engineering-themed crossword puzzle
using a word list that I personally created and added to during over a decade of making puzzles. All of the words are related
to engineering, science, mathematics, chemistry, astronomy, etc. There are no numbnut clues about movie stars or clothing
Hi-Fi: The Guest
This series of comics describing the kinds of reactions
you might expect to receive from various people who are visiting your crib and are introduced to your new stereo setup.
Done in a 1959 edition of Popular Electronics, the scenarios still hold true today, only now you can extend the equipment type
to include your gaming computer and wide screen television, and add to the distractions the guy who is dividing his attention
between you and his smartphone. It's too bad you don't see this kind of stuff in newer publications.
Sherlock Ohms: Case of the
is a regular feature of Design News that presents submissions from readers about troubleshooting challenges and
how they were solved. This story titled "The Subcontractor Zapped the Network" addresses the dangers an unbalanced 3-phase load can cause when
the neutral is improperly terminated. As an electrician
many, many moons ago, I encountered this scenario a couple times during trouble calls to industrial locations. Also
demonstrated is the all-too-common problem of having mindless drones on staff.
How the Slinky Buckles:
Mathematicians have a need to express every aspect of nature in terms of an equation.
That's a good thing... if not a bit obsessive. The March 2013 edition of SciAm has an article about "overcurved rings" such as those in a flat spiral spring; e.g., a
Slinky. If you cut a full rotation of a Slinky
(360°) and join the ends, you find that it does not lay flat due to
overcurvature, but instead it assumes a saddle shape. Another familiar example of an overcurved ring is found in a pop-up tent. Interestingly,
the author describes a method for folding an overcurved ring into a set of three concentric rings that will lay flat. I
immediately recognized it as the method used to package large bandsaw blades, fan belts, etc. It can take a bit of noodling
to figure out how to get the ring into that configuration if you don't have instructions. The video below is one I made
a while back demonstrating how to fold a bandsaw blade.
2nd Edition, by Behzad Razavi. Wireless communication has become almost as ubiquitous as electricity, but RF design continues
to challenge engineers and researchers. In the 15 years since the first edition of this classic text, the demand for higher
performance has led to an explosive growth of RF design techniques. In
RF Microelectronics, 2nd Edition, Behzad Razavi systematically teaches the fundamentals as well as the
state-of-the-art developments in the analysis and design of RF circuits and transceivers. The 2nd edition to reflects today's RF microelectronics, covering key topics
in far greater detail. At nearly 3x the length of the first edition, the 2nd edition is an indispensable tome for both students
and practicing engineers.
RF Cafe visitor Terry
W. recently wrote to me about a topic that ended up mentioning RCA's vacuum tube voltmeter (VTVM) known as the
VoltOhmyst. VTVMs were the era's high-input-impedance multimeter, before field effect transistors (FETs)
came on the scene. The higher a meter's input impedance, the less it loads the circuit under test. Any meter connected across
a circuit appears as a parallel load to the source, so the closer it is to an open circuit, the better. Terry mentioned
how the VoltOhmyst was a key component on test benches of many professionals. You can still buy various models of the VoltOhmyst
Inline Clock Uses
a different type of digital clock that uses a single digit to read out the time serially; i.e., if it the new time is 3:51,
the clock first displays a 3, then a second or so later displays a 5, then finally a 1. Obviously it cannot update the time
every second, but that is not what this kind of timepiece is meant for. It is purely a conversation piece. What makes this
clock, designed and built by David Christianson, is its electromechanical
incandescent display. "The displays make use of a
small piece of film and 12 lens systems to project whatever of 12 images you want to provide." Reportedly, this method was
devised in the 1960s and was very expensive even back then - about $100 per digit. No info is provided about the exact display
used, but it seems any 7-segment display type can be adapted, even a cheap LED.
Pasternack Intros Line of SMP
& SMPM Adapters up to 65 GHz
Pasternack Enterprises' SMP and Mini-SMP, also known as SMPM, are coaxial adapters capable of converting multiple connector
types including SMP, Mini SMP, SMA, 2.92mm, 2.4mm, 3.5mm and 1.85mm connectors. Frequency ratings for these
and SMPM microwave adapters range from 18 GHz to 65 GHz depending on type and style. These new higher frequency
SMP and Mini-SMP versions are compatible and fully mate-able with Corning Gilbert GPO™ and GPPO™ connectors. Pasternack's
new lines of SMP adapters and SMPM adapters utilize passivated stainless steel construction and Beryllium copper (BeCu)
designs for the SMP female connectors.
IEEEIEEE JobSite Career Alerts
The IEEE's weekly JobSite e-mail just
arrived. For those of you who do not subscribe, here are a few of the most useful items in it.
"Reasonable men adapt themselves
to the world; unreasonable ones don't - therefore all progress comes from unreasonable men." – George Bernard Shaw as paraphrased
by Eli Broad
in Inc. BTW, GBS, a widely lauded author, also said, "Assassination is the extreme form of censorship," yet he
was an extreme Fabian Socialist who condoned the extermination of what he considered useless humans "in a kindly manner"
Engineer Needed by TRU
TRU Corporation has announced an opening for
Design Engineer. As directed by engineering management, this position is primarily responsible for product design and
development for customer funded programs and new product research and development. In addition, provides direct support
to business development functions as well as operations on existing products.
PMI Intros 4 to 8 GHz
Low Noise Amplifier
PMI Model No.
is a 4.0 GHz to 8.0 GHz low noise amplifier that typically provides 60 dB of gain. The gain flatness is ±1.25 dB
maximum with a noise figure is 1.75 dB maximum. This amplifier provides a minimum OP1dB of +14 dBm. The VSWR is
2.0:1 maximum into 50 ohms impedance and operates on a single DC supply of +12 to +15 volts with 350 mA nominal
current consumption. This unit is supplied with field removable SMA female connectors and in our standard PEC2 housing that
measures 2.98" x 0.78" x 0.26".
With this miniature foosball game, your
iPad is the app relative to the physical table frame that it
snaps into. Sensors built into the eight familiar control handles send position and rotation information to the iPad's interface
connector, which the foosball software app running on the iPad uses to simulate action on a real table. Sensor technology
has made major advances in the last decade. Buy
Classic Match Foosball on Amazon for $99 w/free shipping. I used to think $99 was a lot to spend on
frivolities, but last week commercials were running for $99 Valentine's Day teddy bears, so evidently my perceptions are
outdated. The company also has a
slot machine for plugging your iPod into.
Beware the Patent Trolls
Nonpracticing entities (NPEs), aka
trolls, think they're getting a bum rap. Those companies that buy up patents and then search to the ends of the Earth for potential cases of infringement say they are only
protecting the original inventors' right to an exclusive claim to innovation, even though the inventor is no longer involved.
An article by Kris Frieswick in the February 2013 edition of
demonstrates otherwise. Frieswick takes the unusually brave step of naming names of the industry's most notorious abusers.
According to his research the practice cost industry $29B in 2011. Typically, a troll serves the accused with a notice of
infringement along with proposed settlement terms which could be a license fee or purchase of the patent. Neither comes
cheap. Software, the biggest target, comprises 74% of all cases even though it represents only 12% of total patents. 90%
of the abused surrender without a challenge and settle out of court. Trolls count on that. Rarely does anyone threaten to
sue a troll, so the business is pretty lucrative with low risk. The best defense thus far has been to prove existence of
"prior art" on file with the Patent Office that invalidates the troll's
patent. They usually retreat back under the bridge upon presentation of that evidence. Here are some related
patent articles on Inc.
Thanks, Applied Computational
Sciences, for Support
ACS designs, develops and sells
Electronic Design Automation (EDA) software tools for RF and microwave engineering applications. ACS's main product is the
LINC2 linear circuit simulator and RF Tools products. LINC2
runs on versions of MS Windows for the PC and compatibles, and is a lower cost alternative to the high-end design and simulation
tools. Visual System Architect, Filter Pro, Amp Pro, Match, TLine, RF Calculato, and De-embed are among the available modules.
Electronic News Circa 1958
There was a time when
"Pong" was a must-play breakthrough bit of futuristic technology with people waiting in line to give it a try, but now nobody
would invest a quarter to play it in an arcade. Similarly, believe it or not, people were mesmerized when listening to the
series of "beeps" coming from Sputnik I satellite during its short life circling the Earth. This item from a 1958 edition
of Popular Electronics shows high school students listening intently to a tape of Sputnik's broadcast. The same "Electronic
News" page reported on the availability of a special record with calibrated sounds for helping to calibrate and troubleshoot
hi-fi systems, and also a new low-wattage public address speaker system installed at Yankee Stadium that needed only 6½
watts per speaker.
Please Welcome "Analyzer
Repair" as a New Sponsor
BRL Test, who has
been an advertiser on RF Cafe since 2010, is now promoting separately their Analyzer Repair website. "We absolutely know analyzer repair." BRL Test's in-house Repair Engineering
Group promises low pricing, experienced metrology technicians (15 years on average) that includes
military PMEL graduates, and parts for repair in stock to guarantee fast turnaround. Popular spectrum and network analyzers
from Agilent, R&S, Anritsu, HP, and Avantest are among their specialties.
to Nicolaus Copernicus
Google's homepage today has
an animated tribute to Nicolaus Copernicus on this 540th
anniversary of his birthday. Only the planets know to exist in Copernicus's day (out to Jupiter)
are shown orbiting the sun, plus our moon is orbiting Earth. Galileo had not yet discovered the large large moons of
Jupiter nor had
Christiaan Huygens found Saturn's largest moon, Titan. Right-click in an empty place on the screen and select View Source to
see the immense amount of code used to generate that animation (turn word wrap on).
UFO Landing Site Markers?
buzz-worthy item du jour hit the news wires in the last couple days. There are many people who's hobby is scanning every
square inch of terra firma as imaged from space by Google Earth
and Street View cameras. I could not find an official organization they can belong to, but most would not want to be identified
anyway lest the black helicopters swoop in to snatch them in the middle of the night. Like the mysterious patterns that
were spotted in the Gobi Desert last year, these black and white patterns show up at U.S. military installations and various
other locations. Reportedly, they were constructed as long ago as the 1950s for calibrating cameras in high-altitude spy
aircraft like the SR-71 Blackbird and the U-2 Dragon Lady (not Bono's group).
The Center for Land Use Interpretation has a collection of aerial images
of the bar codes and some from-the-ground images. For other interesting images, try the
Google Earth Cool Places website, where people continuously upload
AWR App Note for End-to-End
Design of X-band Analyzer
AWR has just published a new Microwave Office® software application note titled, “End-to-end Design and Realization
of an X-band Transmission Analyzer Using AWR Circuit, System, and EM Software.” The note examines the complete flow
and details the design of several critical design elements for this device, which integrates many RF components on a single
printed circuit board (PCB). Design challenges include coupling issues between the RX and TX paths, as well as numerous
distributed elements that required EM simulator-based tuning for optimal performance.
- the remote sensing and reporting of system parameters via radio link - was just coming of age in the late 1950s when this
article appeared in Popular Electronics. It was the age of space payload rocket development (as opposed
to artillery and fireworks rockets), high speed jet airliners, and the Pioneer 1 space probe. There was a great
need to collect data during the developmental and operational engineering project stages in order to ascertain causes for
failures when they occurred and to know what went right when success triumphed. A pinnacle of the newborn
telemetering era was Pioneer 1, which carried an image scanning infrared television system to study
the Moon's surface to a resolution of 0.5 degrees, an ionization chamber to measure radiation in space, a diaphragm/microphone
assembly to detect micrometeorites, a spin-coil magnetometer to measure magnetic fields to...
10th Military Antennas Show
Be sure to sign up early and make your hotel
registration now for Military Antennas West 2013, being
held April 22 - 24, 2013 at the Hilton San Diego Resort & Spa, San Diego, California. Attendees of IDGA's Military Antennas
(West) Summit will have the first look at up-and-coming technologies and programs, as well as revamped initiatives , including,
but not limited to, electrically small antennas, conformal wideband antennas, RF distribution systems, integrated circuits,
the Phoenix project, and much more.
Hittite Intros Groundbreaking
Hittite Microwave has introduced a complete
Multi-GHz Quantizer chip set that enables
quantization of ultra wideband signals from DC to 18 GHz with excellent linearity and low noise. This groundbreaking
Multi-GHz Quantizer solution can facilitate unparalleled levels of performance in test and measurement systems, Bit Error
Rate Testers (BERTs), and Pulse Detection Systems including Pulse Doppler Radars where wideband sampling capability is a
necessity. This combination of ADC and T/H delivers high linearity of >50 dB SFDR up to 7 GHz and low noise of >40 dB
SNR up to 9 GHz at 1 Vp-p full scale level.
Science & Engineering
Crossword for Feb. 17, 2013
Every Sunday I create a crossword
puzzle using a word list that I personally created and added to during over a decade of making puzzles. All of the words
are related to engineering, science, mathematics, chemistry, astronomy, etc. There are no numbnut clues about movie stars
or clothing designers. Enjoy.
PMI Intros 500 MHz to 6 GHz
Low Noise Amplifier
PMI Model number
is a 500 MHz to 6.0 GHz low noise amplifier that typically provides 30 dB of gain. The gain flatness is ±1.0 dB
maximum with a noise figure is 5.0 dB typical. This amplifier provides a minimum OP1dB of +21 dBm. The VSWR is
2.0:1 maximum into 50 ohms impedance and operates on a single DC supply of +12 to +15 volts with 325 mA nominal
current consumption. This unit is supplied with field removable SMA female connectors and in our standard PE2 housing that
measures 1.08" x 0.71" x 0.29".
Thanks to KR Electronics for
Their Long-Time Presence
For over 35 years KR Electronics has designed and manufactured high quality filters for the commercial
and military markets. KR Electronics manufactures all filter types (LC, active, lowpass, highpass, bandpass, bandstop, etc.)
and individually synthesizes filters for special applications. State of the art computer synthesis, analysis and
test methods are used to meet the most challenging specifications.
"IEEE-USA has been one of the loudest critics in Washington of the
H-1B program for more than a decade... Companies have far more control over H-1B workers than they would over an American,
creating a powerful economic incentive for companies to hire an H-1B worker instead of an American. This is legal
under the H-1B program... The H-1B is tailor made for outsourcers because the visas are totally controlled by companies
and H-1B workers can't easily quit... In 2011, over 50% of all authorized H-1Bs in several states went to outsourcing companies."
Silicon-Based RF Front-Ends for Ultra Wideband Radios, by Aminghasem Safarian and
Payam Heydari, comprehensively studies silicon-based distributed architectures in wideband circuits. The book begins with
an introduction of several transceiver architectures for UWB. The discussion then focuses on RF front-end of the
UWB radio. First, the design
and analysis of a performance-optimized CMOS distributed LNA is presented. This is followed by design of novel distributed
RF front-ends for UWB IF-receivers (UWB-DRF). The book continues with the introduction of
a novel distributed direct conversion RF front-end (DDC-RF).
60 GHz Transceiver Products
Hittite Microwave has launched a new,
highly integrated HMC6000LP711E
/ HMC6001LP711E Antenna-in-Package
(AiP) Silicon Transceiver Chipset Solution, which is fabricated with silicon germanium (SiGe) BiCMOS semiconductor process
technology and targets 60 GHz applications such as short range Gbps data links, wireless sensors and test applications.
The HMC6000LP711E AiP solution
combines a 60 GHz antenna with the HMC6000
transmitter IC while the HMC6001LP711E AiP
solution combines a 60 GHz antenna with the HMC6001 receiver IC. Both transceivers are available in 7 x 11 mm QFN plastic packages which support low
cost surface mount PCB assembly and require no experience in handling millimeterwave devices.
500 Injured in Meteor Strike
An epic event occurred in Russia
last night. A huge meteor passed through the atmosphere over the Russian city of Chelyabinsk, setting off a shock wave with
a force great enough to shatter windows and injure nearly 500 people. Any living
Siberian that might remember the
Tunguska event over Siberia in 1908 must have
had a wicked flashback. There is a good possibility it was a chunk of space rock associated with asteroid 2012 DA14, due
to fly by today this afternoon. There could be more to come. Earth is a hard hat area today.
Please Visit Amplifier Solutions
in Appreciation of Support
Amplifier Solutions Corporation
(ASC) is a designer and manufacturer of RF & Microwave hybrid
amplifiers for the military and commercial markets. ASC's thick film hybrids utilize GaAs FET, silicon bipolar transistor
and MMIC technologies to achieve low to medium power output in the 300 kHz to 6 GHz frequency band. Their amplifier
specialties include Low Noise, Wideband, High Power, Low Distortion, General Purpose, CATV (50 &
75 Ω versions), and GaN.
The 'Almighty' Federal Circuit?
Patent Policy & Jurisprudence
Expert witnesses play a big role in most of the court cases that get reported here.
is a law firm specializing in expert witnesses. Every month or so they send me an article about specific court cases that
could be of interest to RF Cafe visitors. This article is entitled The 'Almighty' Federal Circuit? Evolving Patent Policy & Jurisprudence, and asks, in only a slightly
rhetorically manner, the question: "Has the importance of the patent system on the U.S. economy propelled the Federal Circuit
to be, de facto, the most powerful court of the land?" Author Maggie Tamburro, JD, points out that the
U.S. Court of Appeals for the Federal Circuit was established
in 1982 under Article III of the U.S. Constitution(which, perhaps not coincidently, also addresses acts of treason). Reportedly, a whopping
34% of the 2010 GDP derived from IP-related industries. That's an amazing statistic. You will find a lot of interesting
tidbits like this in the article.
AWR Whitepaper on RF System
Software for Wireless RF Links
and correctly predicting cellular, radar, or satellite RF link performance early in the design cycle has become a key element
in product success. The requirements of today's complex, high performance wireless devices are driving designers to assess
critical measurements long before manufacturing begins. A new white paper from AWR, "Understanding and Correctly
Predicting Critical Metrics for Wireless RF Links," highlights the advantages of using Visual System Simulator™ (VSS)
RF system simulation software for detailed insight into the full performance of an RF link in next- generation wireless
what they say: Applied physicists are from Venus; Theoretical physicists wonder why it spins in the other direction." -
Dr. Larry Fleinhardt, from NUMB3RS "Sacrifice" episode
RF Cafe Makes the Top 100
Engineering Websites List
RF Cafe is in the news
again. This note was received yesterday: "I'm contacting you because
RF Cafe is featured on the list of
100 Top Resources for Electrical
Engineers that we published today on ElectricalEngineeringSchools.org Our
readership is mostly composed of aspiring students of electrical engineering. We compiled this list to show them the best
in projects, companies, and general engineering advice. Your site has great articles for someone whose goal is to study
electrical engineering!" Look waaaaaay down near the bottom at #33 (out of 34) in the "Engineering" section to find RF Cafe.
Evidently, I have a lot of work to do ;-)
The concept of a
field effect transistor
(FET) has been around in theory for a long time*, but manufacturable devices arrived in designers' labs not until the early
1960s. This article from the October 1966 edition of QST magazine gives a good introduction to the physics of a basic FET
as well as the junction FET (JFET) and the insulated gate FET (IGFET), all of which are still in widespread use today. What
you learn about them here is applicable today. In fact, I swear some of the drawings are the same ones that appeared in
my college semiconductor physics text books (admittedly from the late 1980s, so not too much of a
Yagi vs. Quad
Here is a story of one Ham's experience
in determining how the performance of his Yagi antenna compared to his identically configured (number of elements, height
off of the ground, etc.) cubical quad antenna. His location was a farm field in Tennessee, back in the mid 1960s,
so there was really not much in the way of obstacles to perturb signals arriving at one antenna versus the other, except
of course when the direction of operation happened to have the antennas in line with each other. Both antennas were tuned
for optimal performance at 14.22 MHz, which is in the high frequency (HF) band.
Replaces Holtek® Products
DS Series Encoder/Decoder
IC from Linx makes it simple to add a robust serial protocol with the ease of DIP switch addressing. The DS lets users
set up to 1,022 unique addresses for reliable communication between devices, similar to older Holtek® products, but with
a stable serial protocol. Testing shows greater than 2x range increase in reliable, stable communication over the Holtek®
protocol, with the DS Series device in serial protocol mode. The market exit by Holtek® from the DIP switch device market
has left many customers in a lurch – Linx is here to help you out.
VE2EK-9Q1EK Ham Shack
A Homebrewer's Paradise
Georges Schleger, United
Nations Director of Snr Broadcast Technologies in 9Q (Democratic Republic of Congo), has quite
an impressive homebrew setup that you will want to see. His equipment assemblies remind me a lot of the many
prototype builds I've done over the years for
various systems for radars, satellite earth stations, and land radio systems. If you're a builder at heart, you will appreciate
Georges' handiwork. Few things beat the satisfaction of connecting a bunch of filters, amplifiers, attenuators, couplers,
and cables together and then making measurements to test your predictions.
RF CAD Drafter Needed
by SEA COM CORP
SEA COM CORP, a manufacturer of marine
and land mobile communications equipment, has an opening for an RF CAD drafter on a contract basis. PADS and Altium experience
required. RF experience necessary. Request occasional visits to the factory. Immediate work available for long term
projects. Self-employed Contractor desired.
Thanks for Putting RF Cafe
in LinkedIn's Top 10%
This notice from LinkedIn
came in my e-mail this morning. According to it,
RF Cafe's LinkedIn profile is in the top 10% viewed in2012. Thanks to everyone who has viewed it. It's nice to be up
that high in the ranking, but being in the top 10% of 200 million members means being in the company of 20 million others.
The U.S. Census Bureau
estimates there are 7.1 billion people in the world today (includes every man, woman, and child),
so that works out to 1 of every 350 people in the world being in LinkedIn's top 10%. While not particularly impressive from
that perspective, as compared to my home state of Pennsylvania's population of 13 million, it makes RF Cafe unique! This
is a good illustration of how statistics can be manipulated
to draw false conclusions.
Hittite PLL with Integrated
VCO for MIMO Architectures
Hittite Microwave has
launched the HMC835LP6GE, a wideband
fractional-N PLL with integrated VCO that generates continuous fractional frequencies between 33 MHz and 4100 MHz.
Targeted at the cellular infrastructure market, the HMC835LP6GE features industry leading PLL & VCO phase noise performance with a PLL figure of merit
of -230 dBc/Hz in integer mode, and -227 dBc/Hz in fractional mode, and typical VCO phase noise of -134 dBc/Hz
at 4 GHz output frequency and 1 MHz offset. Along with industry leading phase noise performance, the
HMC835LP6GE includes advanced features
demanded by modern LTE MIMO radio architectures.
An Amateur Application
of Modern Filter Design
The term "modern" in the title of any
book or article never has set right with me because it is utterly ambiguous about the era to which "modern" refers. Sure,
it sounds good at the time, but when applied to this 1966 QST article, "modern" should be replaced with "four-decade-old."
However, in this case the content is still relevant even thought it was written so long ago (or else
I would not be reproducing it here). It may well have been most people's first exposure to
(Cauer) filters. As you might expect, the rigorous, headache-inducing mathematics is omitted,
but the article does give an example of implementing an audio frequency bandpass filter by cascading a lowpass filter and
a highpass filter. If you are familiar with filter design, you know that because of phasing and inband impedance mismatch
issues you cannot simply butt the two together to yield an equivalent bandpass filter. In fact, the author found it necessary
to insert a 13 dB attenuator between them in order to get acceptable performance.
Tutorial for Conducting
a Patent Search
While conducting a patent
application search for the
nCap Technology product which was posted just a few moments ago, it occurred to me that a lot of people
have never searched for a patent. If you have an idea you believe needs to be protected by a patent, one of the first things
you need to do is determine whether your invention has already been claimed. Another scenario that necessitates a
patent search is when designing a new product to make
sure a patent holder cannot file a n infringement claim against you, and then sue to either prevent its use altogether or
to require a royalty payment (you have no control over the $$$ amount). I know an engineer
whose company is essentially being held hostage to the tune of several hundreds of dollars per unit shipped because of just
such an infringement claim. The USPTO has a well-done video tutorial for first-time patent investigators.. You could potentially save yourself a lot of grief by
learning to do patent searches.
PMI Intros 700 to 1300 MHz
Successive Detection LVA
SDLVA-0R71R3-75-CD-1 is a Successive
Detection Log Video Amplifier that operates over the 700 to 1300 MHz frequency range. This model has a Dynamic Range
of 75 dB, a log slope of 40 mV/dB and a nominal video bandwidth of 20 MHz. The log linearity is ±1.2 dB
typical from -65 to +5 dBm input power levels and a typical TSS of -70 dBm. The limited IF Output is +5 dBm
typical. This model offers very fast rise times of 9nsec and fall times of 25 nsec typically. Other frequency
has launched its new RF and Microwave line of products serving the wireless and military needs. Some of the newly introduced
products are the high power, broadband 0.7-2.7 GHz, and 0.8-2.2 GHz, 75 W mismatch tolerant power
combiners. These combiners
can withstand 180 degree phase mismatch and 0 to full power mismatch at the input ports. Nortec also introduced the newly
designed high power bandpass filter, 0.8-2.2 GHz, with maximum insertion loss of 1.0 dB in the pass band and at
least 20 dB rejection up to 11 GHz. Other new products developed by Nortec are 8W,
general purpose amplifiers
spanning 60-500 MHz and directional and hybrid couplers up to 3 GHz and up to 200 W power handling capability.
Hittite's Low Power 8-Bit
450/900 MSPS ADC's Best SNR
Hittite Microwave has
introduced the HMCAD1512, a 2/1
channel 8-bit ADC sampling at 450/900 MSPS. The HMCAD1512 is ideal for point-to-point microwave links and digital oscilloscopes. The
HMCAD1512 contains two ADCs that can
be interleaved by the user to act as a single channel or two channels. At full speed operation, the
HMCAD1512 delivers an SNR of 49 dBFS
when applied with an input signal of 170 MHz. Total power dissipation at full speed operation is only 650 mW,
including I/O. This performance to power ratio makes the part a perfect choice for low power high performance devices, including
handheld and portable test equipment.
PMI Intros 20 to 40 GHz
Low Noise Amplifier
PMI Model No.
is a 20 GHz to 40 GHz low noise amplifier that typically provides 28dB of gain. The gain flatness is ±2.5 dB
maximum and ±1.5 dB typical with a noise figure is 5.5 dB typical. This amplifier provides a minimum OP1dB of
+15 dBm minimum. The VSWR is 2.3:1 into 50 ohms impedance and operates on a single DC supply of +12 to +15 volts
with 350 mA nominal current consumption.
Thanks to MECA Electronics
for Their Long-Time Support!
Since 1961, MECA has designed and manufactured
an extensive line of RF/Microwave components with industry leading performance including
Directional & Hybrid Couplers,
DC Blocks, Bias Tees and Adapters & Cables.
MECA serves all areas of the RF and Microwave industries including world class network providers and supporting supply chain
infrastructure, and 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.
QSL from Sputnik
Securing confirmation of having made a contact (QSL
in ham-speak) with a radio operator behind the communist Iron Curtain was a real achievement during most of the 20th century.
Russian and Chinese citizens were routinely imprisoned for such activity, and if you did manage to elicit a response to
your CQ (request for contact), there was a good chance it was with a government propagandist posing as a civilian. When
was put in orbit on October 4, 1957, a whole new realm of DXing (long distance communication) opened up by providing satellite
relay paths. Sputnik 1, the world's first artificial satellite, broadcast a series of pulses at 20.005 and 40.002 MHz
that were tracked and reported by both professional and amateur radio operators. Vital data was learned based on the time
and strength of signals that allowed scientists to ascertain the physics of upper atmosphere characteristics. Not wanting
to give the impression that the assistance of the rest of the world's capitalist pigs was needed or wanted (although it
definitely was), virtually no acknowledgement was forthcoming from Radio Moscow...
Webinar: Technology Trends
for Radar Systems
Free Webinar: Technology Trends for Radar Systems, by MWJ and Rohde &
Schwarz, February 12, 12:00 pm EST.
Caution! A video ad that has nothing to do with the webinar will start
playing automatically. This is the last webinar I will post from MWJ because of the ongoing obnoxious practice.
Is Friday's Asteroid Approach
One Possible Future?
Y'all know there's a
meteor due to scream by within 17,200 miles of the Earth on Friday, February 15, that will pass inside the orbits of
many communications satellites, right? Well,
maybe this is the "possible future" that Griffin envisions at the very end of Men in Black 3 (MIB3) for the scenario where Agent K forgets to leave a tip. I'm just say'n it's possible.
media moron ask Bill Nye the Science Guy if the meteor is due to global warming - pathetic!
Electrical Engineering Crossword - February 10, 2013
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). This particular puzzle has lots of abbreviations and acronyms.
Micro 3-D Printer Makes
Dust Mite Size Spacehip
As with most things, once a physical entity
or concept has been produced there is always the 'need' to build one on the macro scale and on the micro scale. Here we
have a 150-mm-long spaceship that was built by German's Nanoscribe GmbH
using a 3-D laser photolithography printer. A scanning electron micrograph was needed to capture a picture of the model
due to its smallness. It took about 50 seconds to create the model out of a photosensitive powder (a video captures the
process). Of course the purpose of the exercise is not to be able to create spaceships the size of a dust mite, but to demonstrate
the capability using an object that the public will be familiar with and impressed by. A micro-size
3-D model of a fountain pen just wouldn't
Good Magazine Articles
from February Issues
Here are a few articles that should be of interest. I try to avoid including articles that are mainly advertisements
for a company's product.
Yet another survey is out of the
most desirable companies to work for according to college types. This one is from AfterCollege.com, "the Leading
Career Network for College Students and Grads."
They all claim that. Here are the results:
My personal #1 would be NASA, then NSA at #2.
Microwave Engineering Handbook Vol 2: Microwave Circuits, Antennas and Propagation,
by B. Smith and M.H. Carpentier. The Microwave
Engineering Handbook provides the only complete reference available on microwave engineering. All entries in the handbook
are written by experts in the area, bringing together an unrivalled collection of expertise on microwave technology. It
covers all of the major circuit types used in microwave systems and also covers antennas and propagation, an area vital
to microwave systems. The emphasis is on fundamental principles and practical hardware, providing a wealth of information
for engineers and system designers.
Here are a few more
conundrums with which to exercise the old noodle. These are puzzlers from a 1959 Popular Electronics magazine, but at
least one of them (#4) will likely prove to be a real stickler unless you have seen a similar resistor mesh problem before.
There are no tube circuits to use as an excuse for not getting them - just resistors, batteries, switches, meters, a motor,
and a couple light bulbs. All four would be fair game to present to an interviewee to see where he/she stands on basic circuit
Iran Airs Flight Footage of
Captured Stealth U.S. Drone
With all the fundamental changing going on in
the country, it's easy to forget about any one particular significant event. Iran just sent a reminder about their commandeering
of our most advanced RQ-170 Sentinel stealth technology drone in December of 2011.
Revolutionary Guard controllers were
able to simply usurp control and guide the craft to a perfect landing on their airstrip. Evidently just as with the highly
classified stealth helicopter than went down during the Bin Laden assassination mission and ended up in a Chinese military
hangar for dissection, the drone capture is no big deal either. I wait with bated breath to see what we yield to next.
IEEE JobSite Career Alerts
The IEEE's weekly JobSite e-mail just
arrived. For those of you who do not subscribe, here are a few of the most useful items in it.
Does anyone out there other than me
remember watching WKRP in Cincinnati?
Here is a video clip of DJ Venus Flytrap teaching a lesson on the atomic model to a street thug in a way he can understand.
Unfortunately, he's using the outdated Bohr model with electrons orbiting the nucleus, but hey, Bohr's work got chemistry
through the middle of the 20th century. With the extreme level of
science ignorance these days in the general
public, maybe PBS should broadcast an entire series on science and mathematics using Venus' method. Maybe they could call
it "Essential Science and Math for Dummies - and Yes, We're Talking About You."
NMIC Ships 10,000th Aluminum
Diamond Heat Spreader for GaN
Nano Materials International Corp. (NMIC) today announced
that it has shipped its 10,000th aluminum diamond
metal matrix composite heat spreader for use in GaN RF power transistors and MMICs. The achievement is a significant
milestone for acceptance of NMIC's aluminum diamond MMCs and for manufacturers of defense and commercial RF power amplifiers
who must dissipate the heat generated by high-power-density GaN devices. Orders for NMIC's aluminum diamond MMCs have continuously
increased as tests by GaN device, power amplifier, and system manufacturers have validated the benefits of the technology
and as NMIC has optimized its processes so that it adds minimally to the cost of each device.
College Fund vs. KickStarter
I like reading comic strips just
for the fun of it. Many of the newer ones are too political or have nasty characters, but some do a pretty good job of addressing
today's societal concerns in a humorously clever way without insulting the audience. Moderately Confused™,
by Jeff Stahler, is one of them. In this one from February 5, the son is asking his parents if they would prefer to invest
in his Kickstarter project rather than in a college fund. In an
age where less than half of college graduates are getting jobs in their chosen fields of study, and where payback on exorbitantly
high college costs could take a lifetime, rethinking the direction Junior should take might be a worthwhile exercise. A
lot of people end up much happier in life pursuing
a dream/idea early on rather than starting out with four years of college then being at the mercy of the corporate world.
Not everyone would succeed in a start-up venture while going to the School of Hard Knocks rather than to a university, but
then most aren't succeeding after graduating nowadays, either. Our daughter Sally, a straight-A student in college, elected
to get Associates' degrees in business and logistics, then start a horse
riding school instead of pursuing Bachelor's degree. She has never regretted the decision.
Thanks to JQL Electronics
for Long-Time Support
JQL Electronics is a leading manufacturer of
microwave ferrite isolators & circulators, directional
couplers, power divider/combiners, ceramic filters, power transformers, waveguide to coax adapters, and power supplies. In
addition to their design capability, JQL has strong production capability to deliver its products. Lead time is
among the shortest in the industry.
Pasternack Releases Line of
Medium Power Attenuators
Pasternack Enterprises introduces
their new line of 50 Watt
power attenuators. This innovative line of medium power attenuators offers one of the most comprehensive selections
of RF connector combinations available, thus eliminating the need for coaxial adapters or custom cable jumpers to change
connector types. The new medium power 50 Watt attenuators from Pasternack Enterprises can be ordered with any combination
of passivated stainless steel SMA, TNC and N connectors as well as silver plated brass 7/16 DIN connectors. Pasternack medium
power RF attenuators operate from DC to 18 GHz depending on connector configuration.
Antenna Design Automation
Parameterized EM Analysis
Antenna Design Automation with Scripting
and Parameterized EM Analysis, by MWJ and Agilent, February 7, 1:00 PM ET. Full-wave 3D EM software is an indispensable
tool for designing RF antenna structures. However, complex array-based antennas can be cumbersome to set up and analyze
in traditional EM software tools. Agilent EMPro has integrated Python based scripting that provides the user the ability
to automate geometry creation, simulation and data analysis. This, combined with parameterization of key design variables
can greatly accelerate the development process. This webcast will illustrate the advantages of scripting and parameterization
by considering the example of an MxN element Microstrip Phased Array patch antenna.
YL New & Views
"YL" in amateur-ese stands for "young
lady." It refers to any ham operator of the female gender regardless of age. I don't know how many women were Hams in 1966
when this article appeared in QST, but according to Communities of the Air: Introducing Radio to the World, author
Susan M. Squier, by 2003 women made up 40% of new amateur radio license applicants. Judging by amateur radio club rosters
and field day events, YLs don't make up anywhere near 40% of the Ham population, but maybe they just tend to shun the public light. A 2008 presentation
on the YL Radio Website estimated 15% in 2000. I searched around the Young Ladies Radio League (YLRL), American Radio Relay
League (ARRL) and the Federal Communications Commission (FCC) websites for current statistics but could not find anything
specifically about the percentage split between males and women...
NuWaves Selected to Provide
RF Subsystems for ViaSat
NuWaves Engineering announced today that two of its module-level
RF products, the Multi-Octave RF Upconverter (MORF™) and the
ConvertaWave2™ Downconverter, have been selected by
ViaSat Inc. to be embedded in the company's VRG-1000 RF Signal Environment Generator product line. NuWaves'
MORF accepts a range of intermediate
frequency (IF) signals and delivers a user selectable RF output between 2 and 3000 MHz for RF transmission. On
the RF receiver side, NuWaves' ConvertaWave2 accepts
an RF signal from 200 to 2500 MHz and delivers a bandwidth-filtered IF of 70 MHz, ready for baseband processing.
Both modules are compact, offer highly precise tuning resolution, and provide superior out-of-band interference rejection.
“We are very proud that ViaSat selected these commercial-off-the-shelf products to serve as key RF subsystems in their RF
signal environment generator products,” said Jeff Wells, President and CEO of NuWaves Engineering.
SynRF for Matlab Circuit
Analysis Software - Free!
Heuermann HF-Technik GmbH is offering their
Matlab-based circuit analysis tools as a free download. From their website; "SynRF allows you to perform
the synthesis of RF circuits in seconds.SynRF calculates the element values and illustrates the transfer function over frequency. This gives
you the information of the bandwidth of the circuits." SynRF supports the calculation of more than 50 circuit types including
various attenuators, impedance transformers from lumped and distributed elements, phase shifters, resistive and reactive
power dividers, couplers, transmission lines, transmission-line-based inductors and capacitors, even and odd mode blockers,
baluns, lumped and distributed resonators, band pass filters, and a diplex filter. The price is definitely right.
Webinar: The Effects of
Jamming on GPS/GNSS Signals
GPS Interference & Spoofing: Origins, Effects
and Mitigations for the Military and Civil Communities, by MWJ and Rohde & Schwarz, February 6, 2013, 1:00 PM ET. Overview:
After a review of GPS signal structures and current satellite constellation status, this webinar provides a tutorial examination
of how interference affects GPS signal reception. In particular, interrelations between jammer spectrum and GPS signal spectrum
are explored. The Betz equation for computing cross coupling between an interference source and a spread spectrum signal
is introduced in the context of GPS signals and the role of signal and jammer RF propagation is considered.
CAUTION: A video ad will probably start playing - tell MWJ to stop this annoying
2850 to 3050 MHz S-Band VCO
Z-Comm announces a new RoHS compliant VCO model in
the S-band. The SMV2950A-LF operates
at 2850 to 3050 MHz with a tuning voltage range of 0 to 2.5 Vdc. This compact VCO features phase noise of -85 dBc/Hz
@10 kHz offset while operating off a 3.0 Vdc supply and typically drawing 15 mA of current. The
SMV2950A-LF provides the end user typical
output power of 3±3 dBm into a 50 Ω load while operating over the industrial temperature range of -40 to 85 ºC.
This robust VCO suppresses the second harmonic to better than -15 dBc and covers the frequency range with a tuning
linearity of better than 1.1:1.
It is good practice to occasionally rehash old topics for two reasons. One is that
there are always new people coming to the website and have not seen the information before (at least
not here). The second is because most people, especially
RF Cafe visitors, experience information overload just about every day so a lot of unused data gets pushed off the bottom
of the memory stack. Although admittedly a bit self-serving, I want to remind you - or inform you for the first
time as the case may be - about the really useful
WayBack Machine(borrowed from Mr. Peabody's
WABAC machine) at archive.org. There, you have a good chance of finding long-gone web pages. Paul van Oorschot,
of ResistorGuide.com, just found the long ago disappearing article
titled Near Field vs. Far Field from the equally mysteriously disappearing Conformity magazine website.
Are You a Skeuomorphist? (skeuomorpher in today's vernacular)
Scientific American's David Pogue wrote an article
titled "Out with the Real*," which laments the continued widespread use of skeuomorphs in software. According
to Dictionary.com a skeuomorph is "an ornament
or design on an object copied from a form of the object when made from another material or by other techniques." Familiar
examples include animated book pages on e-readers that appear to be turning like a physical book, the desktop wastebasket
icon, and clickable buttons for options. He argues that such an attachment to the past holds back progression toward the
future. In a sense he's correct insofar as a new generation of people who do not really need to transition from a non-computer
world to a computer-centric world - the technology is now introduced almost at birth these days. Entirely new software interface
strategies can be designed that more effectively assist the user with operations if the old crutches are abandoned. Human
evolution is spinning its wheels, so to speak (dang, I just skeuomorped). Of course if that
new software paradigm is taken too far, we will need to start applying
skeuomorphisms to physical objects to make them simpler to use for the person who has lived his life on a computer since
the time mom and dad gave him an iPhone-shaped pacifier to teethe on. *SciAm stupidly uses different
titles for print vs. online articles.
PMI Intros 900 to 930 MHz,
6-Bit Phase Shifter
PMI Model No.
is a 900 MHz to 930 MHz, 6-BIT digitally controlled phase shifter having a LSB of 5.6 degrees. The insertion loss
is 7 dB typical, 7.5 dB maximum with a typical VSWR of 2.0:1. This is a high speed phase shifter that can switch
from one phase state to the next in typically 250 nsec. This model will operate at input power levels up to +14 dBm
CW and operates on a DC power supply of ±15 VDC. The housing measures 2.0" x 2.1" x 0.5" and is painted gray. Other
frequency ranges are available.
Please Visit Coaxial Dynamics
in Appreciation of Support
Coaxial Dynamics has been a leading manufacturer of
precision equipment for the measurement and termination of RF power for over 30 years. Their equipment is used by engineers
and technicians in a wide variety of applications throughout the world, and they have sales offices all over the world to
serve your needs. Coaxial Dynamics' dual-directional wattmeters appear
in the ARRL's monthly QST magazine.
has been added to the RF Cafe vendor listings. They are a
manufacturer of drop-in and connectorized hybrids & couplers, combiners & dividers, filters & diplexers, isolators &
circulators, coaxial & optical attenuators & adaptors, terminations, surge protection, delay lines, connectors,
cable & cable assemblies, laser diodes, and custom assemblies. 978-772-3767 | Devens, MA
Everything You Ever Wanted
to Know About Resistors!
After spending a while perusing Paul
van Oorschot's ResistorGuide.com website, I can say with
a high degree of confidence that if there is anything you need to know about resistors, you will find the answer there.
If it is the fundamentals you're after like power dissipation, resistance tolerance, stray inductance and capacitance, and
how Ohm's law applies, Paul's got you covered. How about
package configurations, color codes and alphanumeric markings? Yep, that's on the website as well. So also is info on resistor
compositions (metal film, metal oxide, carbon, et al), resistor physical configurations (fixed, variable, thermistor, magneto
resistor, others), and applications (heating, current limiting, voltage division), and even schematic symbols for each.
Oh, and did I mention all of the instructional videos? It is probably no exaggeration to say that if you cannot find the
information you need about resistors here, you're not going to find it anywhere.
Nitronex Has a Senior Product
Senior Product Engineer (ENG13001), Location: Durham, NC, Department: Engineering. Basic Function:
Senior level experienced engineer to assist in the development and design of MMIC RF and Microwave products. This position
will drive MMICs and discrete devices from design engineering to production release. This includes product characterization,
datasheet creation, application board development, automated test development, statistical analysis and specification definition.
Experience: 5 to 10 years RF product development experience with at least four years in product engineering, applications
or design field developing RF semiconductor products.
direction around him, he will rely on other people's knowledge. The bad news is that this engineer will never know all of
engineering; the good news is that he doesn't have to. The world doesn't work that way anymore." –
Robert Lucky, January 2013 Spectrum
Many Thanks to RF Dude
Consulting for Support
Lance is always the first person I refer people
to when I get a call looking for an RF/microwave circuit and system designer. Says Lance, "When you hire
RFdude.com for a project you receive design and analysis
services in the realm of applied research and development. We appreciate the big picture and choose to operate where
we can do our best work for you. Our operation has extremely low overhead which allows us to be very responsive and
efficient. Experience is in medium volume production where 'design for manufacturing,' 'design for test,' and overall solution
cost have been very important." Please see Lance's resume page for
Patent Term Calculator
Compliments of the USPTO
The United States Patent and Trademark
Office does not calculate expiration dates for patents. In response to patent owner and public inquiry, the USPTO is
providing a downloadable patent term
calculator in Excel format as a resource to help the public estimate the expiration date of a patent. The
calculator can be used to estimate the expiration
dates of utility, plant, or design patents. The calculator contains prompts to enter specific information related to
the patent in order to help in estimating expiration dates.
Wireless Crossword Puzzle
February 3, 2013
Wireless Engineering-themed crossword
puzzle in the bathroom at your own risk; it's going to take a while. The words are not real hard, but there are 413 of them.
It has been a while since I made one this large. If you insist on indulging your habit against my admonishment, you'd better
have some Prep H on-hand (truly bathroom humor).
You're Not Very Smart After All
Space Odyssey, released in 1968 and based at least in part on Arthur C. Clarke's 1948 novel The Sentinel,
was more than just a science fiction movie.It was a reflection on the public's and even some of the scientific
community's trepidation over the potential power of run-amok computers to be used for or even themselves commit evil (e.g,
HAL 9000). Fear of the unknown is nothing new. Noted mathematicians and computer scientists quoted in this 1950 article
from The Saturday Evening Post worry about robots (aka computers) "going
insane" or being used by the likes of Hitler and Stalin to dominate the world with totalitarian rule. Others, however, have
a more optimistic outlook: "The men who build the robots do not share these terrors. Far from destroying jobs, they testify,
they will create new ones by the hundreds of thousands, just as the industrial revolution eventually did. Moreover, most
of the robot builders would make book that in time 'thinking machinery' will bring about a happier, healthier civilization
than any known heretofore. What the odds on Utopia...
Skyworks Does TI Reference
Design for Smart Energy Apps
Skyworks Solutions has secured a reference design with Texas Instruments Incorporated
(TI) for smart energy, industrial and networking applications including electric/gas/water meters, street lighting, telematic
and tracking systems. Skyworks' highly integrated, power efficient front-end solutions are in volume production and compatible
with single-chip transceivers for wireless systems requiring high performance at low power and voltage. "TI is delighted
to be collaborating with Skyworks to develop a new reference design using TI's sub-1 GHz RF performance line transceiver
and Skyworks' front-end solutions," said Terje Lassen of TI.
RACEP (Random Access and Correlation for Extended
Performance), was an early form of
hopping spread spectrum (HFSS) devised by the Martin Company (now Lockheed-Martin). It was used for secure voice communications
and worked by sampling speech in small 'slices' and then transmitting each slice modulated onto a carrier whose frequency
was determined by a predetermined sequence of center frequencies. A receiver with a matching sequence key would then decode
the speech and, with appropriate filtering, reassemble it into its original content. President John F. Kennedy had such
systems at his disposal whether on the road or in the Oval Office. General Electric (GE) had a different idea it dubbed
'Phantom' that spread the signal over a very wide bandwidth. Today, we refer to it as Direct Sequence Spread Spectrum (DSSS).
Not to be outdone, Hughes Aircraft...
Please Visit DCH Systems in Appreciation of Their Support
Modern Antennas, by S.
Drabowitch, A. Papiernik, Hugh Griffiths, J. Encinas, and B.L. Smith. A complete and rigorous treatment of design principles
for modern antennas, including chapters on signal theory and signal processing antennas, radar and polarimetry. Contains
significant new material on antennas for mobile communications to supply a complete picture of antennas for
modern radio communications applications. Says a reviewer,
"This is an excellent book both technically and because it gives a 'fresh' European perspective on modern antenna engineering
written by practicing antenna designers."
vida RF Magazine Ad
Even in hard economic time like the entire world
is experiencing now, it is necessary to continue advertising campaigns in order to capture as large a piece of the consumer
pie as possible. I offer my advertisers an opportunity to have their magazine ads posted here since they are able to present
more information than can be accommodated on one of the many Product
Vendor pages on RF Cafe. The newest addition was supplied by vida RF,
a manufacturer of RF cables, and many types of RF / microwave components like coupler, attenuators, and baluns.
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while tying up your telephone line, and a nice lady's voice announced "You've Got
Mail" when a new message arrived...
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