Technologies has published a white paper titled, "The
FCC Certification Process: Going Wireless." Author Justin Hopper writes, "The FCC certification process for
products with wireless features can be complicated and daunting. Increasingly, customers are expecting wireless
features, yet many manufacturers hesitate because of the uncertainty of the certification process. This article
discusses the FCC certification process for the United States and shows that it is not as bad as it may seem.
Other countries have different processes and procedures, but that is beyond the scope of this article...<continued>
" This article is one of the first entries in Linx's
Test Equipment Rentals (ATEC), supplier of complete testing solutions for EMC applications
in military/defense, telecommunication, commercial CE, aerospace and automotive markets, today announced it has
been awarded ISO/IEC 17025-2005 & ANSI/NCSL Z540-1-1994
accreditation for calibration by the American Association for Laboratory Accreditation
(A2LA). Accreditation to ISO/IEC 17025 is obtained through an assessment of a laboratory’s
compliance in carrying out specific tests and calibrations precisely to the scope of accreditation.
in the 1960s, Robert Balin created many quizzes on various electronics topics for Popular Electronics
magazine. I have already posted a couple dozen of them. Here is the latest one on the subject of
of Measure commonly found in electronics work. I missed the one for the tape deck, but then I don't ever remember
concerning myself with the electrical and magnetic characteristics of tape decks.
Czech Technical University (CTU) in Prague challenges its graduate engineering students
to master the basic design of microwave circuits and subsystems and become familiar with the concepts of active
and passive microwave and millimeter wave circuit designs. CTU uses AWR’s
Office circuit design software and AXIEM EM simulation software extensively in both coursework and research
because it is fast to learn and easy to use, enabling students to successfully master the complex concepts of
Test Equipment Rentals has signed on to help deliver RF Cafe to you through paid advertising. ATER provides the
latest models of test and measurement equipment from top
name manufacturers like Agilent, Fluke, Anritsu, R&S, Tektronix, and Yokogawa. Our primary focus is providing
a complete rental solution of test and measurement equipment to industries such as Aerospace, Defense, EMC, and
suppose the term "Subminiature" as it applies to electronics components is as relative as the word "Modern" is
in book titles. They might be accurate at the time of the writing, but passage of time renders them ambiguous.
Subminiature in 1957 meant anything other than full-size vacuum tubes, huge power transformers, multi-layer wafer
switches, and hookup wire larger than AWG 20. The advent of
peanut tubes, very early versions of transistors and solid state diodes, and ever-higher operational frequencies
permitted component sizes to be shrunk by a factor of two or more. Rather than using a pistol-style soldering
gun or a soldering iron designed for assembling copper guttering, a precision pencil-type iron could be used and
greasy tools from the garage no longer sufficed for turning screws and nuts. A lot of the material in this article
is still useful for hobbyists and even electronics professionals in the lab.
so the Radar Tech Hall of Fame is an RF Cafe creation, but the USAF hasn't done it and the world deserves one.
Our newest inductee is MSgt. Floyd Hinkson, ret. Floyd had quite
an extensive career working on primarily mobile radar systems including the MPN-1, MPN-11, MPN-13, MPN-14, and
TPN-19. I'd say he's probably one of foremost authorities on tube-based mobile radars (although the TPN-19 is
solid-state). Floyd encourages his fellow radar techs to get in touch. If you send me an
e-mail, I'll forward it to him.
announces a new RoHS compliant VCO model
CRO1320A-LF for the
SATCOM market. The CRO1320A-LF is designed to cover 1320 MHz with a tuning voltage range of 0.5 to 4.5 Vdc.
This single frequency, high performance VCO has been optimized to feature extremely low phase noise of -120 dBc/Hz
@ 10 kHz offset while operating off a 5 Vdc supply and typically drawing only 29 mA of current.
Output power of 3±3 dBm into a 50 Ω load while operating over the extended commercial temperature range
of -40 to 85ºC.
Microwave is a leader in technically differentiated electronic and radio frequency
ferrite circulators and isolators that connect, protect
and control critical systems for the global microwave electronics market place including commercial and military
wireless telecommunications. Dedicated to R&D of standard and custom design quality ferrite circulators and
isolators from 380 MHz to 23.6 GHz.
Electronics is a leading turn-key PCB assembly manufacturer in the EMS Industry offering one-stop
PCB assembly services including PCB fabrication, parts procurement
and final circuit board assembly. Expertise in DFM (Design for Manufacturing) checking
for your every order. Ideal service for PCB prototyping and low / high volume production runs.
Microwave Corporation is pleased to announce the release of the
Hittite’s 2013 Product Selection
Guide summarizing over 1100 products including 22 new products. New for this publication are GaN PAs, an I/Q
downconverter and sub-harmonic MMIC mixers. The Selection Guide is organized by RF & microwave, analog &
mixed signal, clocks & timing and LO frequency generation IC sections along with modules and instrumentation.
Hittite's 2013 Off-the-Shelf Newsletter includes 17 new product highlights & articles and company news organized
by market application.
Television News ran a two-part article on the state of the art of computers in the late 1950s. It had only
been since ENIAC's (Electronic Numerical Integrator And Computer) debut in 1946 at
Massachusetts Institute of Technology (MIT) that the public
(or science community for that matter) was getting used to regularly hearing about computers in the news.
By 1957 there were many companies popping up with
computer offerings. Originally the exclusive purview of university research labs and defense installations,
the size and cost of computers was moving into the realm of affordability by corporations that used them for accounting
and bookkeeping, and in some cases even rented idle time to outside users. Desktop PCs and notebook computers
were still the realm of crazy dreamers.
Remington Rand "Univac" (UNIVersal
Automatic Computer) computer was delivered on March 31, 1951. Its main memory consisted of liquid mercury
delay lines arranged in 1000 words of 12 alphanumeric characters each. A Univac famously calculated the first
presidential race forecast - Eisenhower vs. Stevenson - and was correct! This 1957 report mentions how "giant
electronic computers no longer rank as laboratory curiosities or frightening science-fiction robots." The Unisys
company is today's descendant of Remington Rand.
Matrix Synthesis (CMS) tool facilitates synthesis of N+2 coupling matrices for
Chebyshev bandpass filtering functions, with arbitrary finite-position transmission zeroes. Filter orders up to
12, arbitrary placement of complex transmission zeroes, S-parameter file (s2p) generation,
dvanced graph and marker functions, much more.
warfare is emerging as the new war fighting paradigm of the U.S. and many of its allies. This book is the first
in the field to address communication
electronic warfare (EW) systems in the context of information warfare. Authored
by a recognized leading authority, the book includes a unique formulation of EW system performance and presents
results of system simulations that have not appeared previously in any related literature. Essential reading for
EW engineers and researchers working in defense, aerospace, and military capacities, the book explores the properties
of information, the properties of information communication means, information theory, and EW system architectures.
is the latest set of job-related articles referenced from the IEEE's The Institute newsletter that seem
to be worthwhile... IMHO, anyway.
When Business Conduct
Might Be Business
For Consultants, Social
Conference Focuses on
Peter Johnson: From Janitor
to NASA Engineer
Civil Aeronautics Administration (CAA), born in 1940 and now known as the Federal
Aviation Administration (since 1958), was established originally to regulate the
burgeoning commercial airline and cargo transport air traffic as well as the private aviation activity. According
to an FAA document, on April 3, 1947, CAA controllers began in-service evaluations of the ground approach control
(GCA) radar system at Washington National and Chicago Municipal airports. It was
commissioned for officially use by the CAA on January 7, 1952, at Washington National Airport. This story from
a 1957 edition of Radio & Television News reports on the system upgrade to
long-range radars that would permit, eventually, continuous coverage across the entire USA.
RF Systems invites you to visit them at their booth (#206) at the
EMC2013 show in Denver, Colorado, from August 5 - 9.
Technik Industries, Inc. of Clearwater, Florida has purchased
Nova Microwave of
Morgan Hill, California. Nova Microwave designs and manufactures RF/Microwave isolators and circulators for both
commercial and defense applications. With almost 20 years of experience in the microwave business, Nova Microwave
offers a number of different styles from drop-ins to surface mounts. The frequency ranges from 380 MHz
to 23.6 GHz with average power ratings from 2 to 250 watts.
is a supplier of custom-made thin metal parts. Chemical etching, metal stamping,
RF shielding, or any custom part made out of metal. RF/EMI shielding,
metal stamping, lead frames, filter screens. Samples are available.
has said in many newspapers and over his signature that it would be possible to transmit the human voice across
the Atlantic before many years. Based on these absurd and deliberately misleading statements, the misguided public...
has been persuaded to purchase stock in his company." - U.S. District Attorney, prosecuting Lee DeForest for fraud
a break and work this week's microwave
engineering themed crossword puzzle. All the words are pulled from a hand-built list of terms, names, and
abbreviations that have only to do with science, mathematics, and engineering. If you want a crossword with names
of movie stars and obscure countries, try the local newspaper. If you want to exercise your nerd knowledge, this
is the one for you.
Corp. is the leading designer and manufacturer of
RF Shielding and EMI/RFI Isolation Products
for printed circuit boards and electronic enclosures. Orbel also specializes in thin gauge
Photo Etched Metal Parts
and Precision Metal Stampings made
from a wide variety of material options.
July 3, 2013, the EAA AirVenture Museum flew a
Trimotor (aka "Tin Goose") into Erie International Airport, and offered rides
for $75 per seat. Normally, rides in vintage aircraft cost much more than $75, so Melanie and I jumped at the
chance. We got about a 16-minute ride out to Presque Isle and around Presque Isle Bay. The experience of flying
in an aircraft with three radial engines was definitely worth the investment, especially since it was a cool day,
winds were light, and the visibility was unlimited with a little haze. Even with finely balanced propellers and
9-cylinder radial engines, the vibration level was very notable. Unless you are an airplane lover who responds
to such stimulation the way a newborn baby responds to its mother's heartbeat, I can understand how hours-long
flights might have been a bit wearisome...
Microwave announced four new GaN MMIC power amplifier products which offer significant performance, size and durability
advantages for communications, test instrumentation and radar systems operating in the 2 to 20 GHz frequency
range. The HMC1086F10 is a 25 W GaN
MMIC PA which operates at 2-6 GHz. It typically provides 23 dB of small signal gain, +44 dBm saturated
output power, and delivers +46 dBm output IP3 at +33 dBm. The
HMC1087F10 is an 8 W GaN PA which
operates at 2-20 GHz. It typically provides 11 dB of small signal gain, +39 dBm of saturated output
power, and +43 dBm output IP3 at +28 dBm.
are a few useful job hunting (and keeping) tips from around the web.
2013 Engineering Jobs
Is a 2-Page Resume
How to Achieve Likeability
Can I Turn Down an Offer
I've Already Accepted?
How to Think Like a Leader,
by Jack Welsh
Ignore These 10 Outdated
Job-Search Advice Tips
5 Ways to Better Position
Yourself For a Pay Raise
Include in a
announces a new dielectric resonator VCO model
DRO12600A for the test and measurement
market. The DRO12600A is designed to cover 12600 MHz with a tuning voltage range of 0 to 12 Vdc. This
unmatched VCO has been optimized to feature extremely low phase noise of -102 dBc/Hz @ 10 kHz offset
while operating off a 5 Vdc supply and typically drawing only 23 mA of current. The low noise DRO12600A
is designed to deliver a typical output power of 0±3 dBm into a 50 Ω load.
looked over out broad range of cavity, ceramic, LC, and SAW filters, duplexers, triplexers, and
multiband combiners recently? If you do, you’ll
find new models and a greater range of models than ever before.
visiting RF Cafe (other than by accident) almost certainly knows of Drs. Bardeen,
Brattain and Shockley fame for their transistor invention while jointly working at the Bell Telephone Laboratories.
The trio shared
The Nobel Prize in Physics in 1956. Bell was so proud of their employees' efforts that they ran full page
advertisements to boast of the accomplishment. This one appeared in the February 1957 edition of Radio & Television
News. Alas, Ma Bell's moment of glory was a bit diminished by needing to add a footnote admitting that Drs. Bardeen
and Shockley no longer work there.
has announced the following fully-funded engineering positions in Camarillo, California.
Launched in July 2012 as a spin-off company of L-3 Communications, Engility possesses more than 40 years of
combined experience across nearly 70 different legacy companies.
you read or hear news stories about the total amount of taxes you pay, the number can seem unreasonably high until
you account for payroll (federal, state, local), standard point-of-sale (state, local), special PoS (cigarette,
gas, appliance disposal), utilities (electric, phone, heating fuel, water), and multitudinous other hidden taxes.
Per CNN today: "Your wireless carrier isn't the only one pocketing money when you pay your
cell phone bill. Local, state and federal governments,
911 systems and even school districts tack on taxes and surcharges to your wireless bill that end up costing American
cell phone customers an extra 17.2%, on average, according to the Tax Foundation. That's up from 16.3% fifteen
VidaRF, the phrase "Providing Simple Solutions for Complex Connections" is more than just a slogan – it’s a mindset,
a mission, and a driving force behind everything we do. Our pledge is to design and distribute high performance,
cost effective RF and Microwave products to fit each customer's unique applications.
Attenuators, cable assemblies, connectors & adapters, isolators, circulators, couplers, and power dividers
are among our offerings.
to Radar Systems, by Merrill Skolnik. Since the publication of the second edition of "Introduction to Radar
Systems," there has been continual development of new radar capabilities and continual improvements to the technology
and practice of radar. This growth has necessitated the addition and updating of the following topics for the
third edition: digital technology, automatic detection and tracking, Doppler technology,
airborne radar, and target
recognition. The topic coverage is one of the great strengths of the text. In addition to a thorough revision
of topics, and deletion of obsolete material, the author has added end-of-chapter problems to enhance the "teachability"
of this classic book in the classroom, as well as for self-study for practicing engineers.
rarely look at website server statistics for RFCafe.com
because my focus is on providing useful content and not trying to devise clever schemes to trick or coerce visitors
into clicking on ads. Adding significant material on a daily basis since 1999 has resulted in prominent page rankings
and search engine positions for many relevent keywords and phrases. My philosophy is to provide you with as little
annoyance as possible while also creating a venue where companies will pay me to present their goods and services.
An unwillingness to curb my content and comments to satisfy some peoples' ideas of correctness has undoubtedly
cost me visitors and advertisers, but c'est la vie. I am always a bit dubious about what data are included in
the numbers and charts presented by many websites, so I never make absolute claims for any statistic. A popular
tactic is to include numbers that include every item requested from the server with each page view, which includes
images and any files loaded into an inline frame. Here are a few charts for June 2013, in case you care. Notable
points are the pronounced dips in page views during weekends and for some odd reason, the top search phrase for
June was "density of sand."
Linx Technologies 250 Series
RF transceiver module is designed for reliable bi-directional transfer of digital data over distances of up
to 4 miles. Operating in the 902-928 MHz ISM frequency band, the module is capable of generating +23.5 dBm
into a 50-Ω load and achieves a typical sensitivity of –105 dBm. This high output power gives the module
remarkable range and also helps overcome noisy environments at shorter ranges. The module implements a Frequency
Hopping SS protocol with a UART serial interface that can be connected directly to microcontrollers, RS-232, RS-485
converters or USB adaptors.
this article on component (resistor, capacitor, and inductor) measurement was written,
readily available, inexpensive multimeters were not in existence. For about $20 you can now buy a brand new handheld
DMM that will make very accurate resistance measurements and reasonably good capacitance measurements at frequencies
up to a few MHz, where lead inductance starts to be significant (test frequency is usually
only a few kHz). Finding an affordable, accurate inductance meter is another story. Cheap LCR meters can
be purchased on eBay, but don't be surprised if the quality is not very good. The most accurate
measurement method uses a frequency in the realm of actual operation, and this article presents methods that
will allow you do do just that by using typical bench top instruments.
PS-500M2G-8B-SFF is a Stare-of-the-Art, 8-Bit Digitally Controlled Phase Shifter that operates over the 500 MHz
to 2.0 GHz frequency range. This model has a typical insertion loss of 10dB and offers 360 degrees
of phase shift via 8-Bit TTL control. The phase shift error is less than ±10 degrees and the amplitude error is
less than ±1 dB. The switching speed is 500 nsec maximum.
take a moment and vote in this poll. No sign-in-required. Results are displayed automatically. Thanks!
Google Doodle is actually a goofy video game that celebrates
the whole Roswell UFO/alien thing. I would like
the 10 minutes of my life back that I spent playing it through to the end. Per
Wikipedia, "On July 8, 1947, the
Roswell Army Air Field public information officer Walter Haut, issued a press release stating that personnel from
the field's 509th Operations Group had recovered a 'flying disk', which had crashed on a ranch near Roswell."
The truth is out there.
you have any trouble sounding condescending, find a Unix user to show you how it's done." - Scott Adams, Dilbert
creator. I can remember when that was true, but I'm not so sure it is anymore. A contemporary example might be
to find an Apple product user.
receivers are absolutely essential in
work. The need has driven major advances in the state of the art of cryogenically cooled front ends with noise
temperatures near absolute zero. Antenna technology has also benefitted from radio astronomy due to the need for
precision steering and narrow beam widths. Phased arrays (aka interferometers) for
interstellar targets requires that element spacing be large enough to require separate antennas as the elements,
which creates a very large effective aperture, hence greater angular resolution. Networks located continents apart
are synchronized with the use of atomic clocks to allow signal time of arrival and therefore phase to be accurately
measured. This story gives some of the early efforts.
is an international supplier of noise sources and test equipment. Noise is their focus, and only business, so
they can help yours. NoiseWave provides their customers with high quality standard
and custom noise test solutions to meet commercial and military wireless applications.
was founded by Engineers for Engineers. Amplical is a leading supplier of quality RF microwave components. Utilizing
the latest in RF Microwave technology, 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. Products are typically available from stock. GaAs technology.
week I create a new custom crossword puzzle
that uses only personally selected words pertaining to engineering, science, mathematics, aeronautics, metrology,
chemistry, tech companies and leaders, etc. There are no words or clues for movie star names, sports heroes, or
obscure villages in Timbuktu.
a given semiconductor compound, the maximum operational speed of a transistor is governed pretty much by its gate
thickness. Capacitance and impurities along with lithography precision and accuracy are the culprits. Shrinking
gate sizes and growing crystals with greater purity has driven operational speeds upward significantly over the
years. An equivalent set of issues plagued vacuum tube development a century ago. The physical spacing of grid
elements wrt each other as well as to the cathode and plate placed an upper limit on amplification bandwidth.
As always, judicious study of the underlying causes led to the development of new designs that, along with improved
manufacturing techniques, overcame existing barriers and, also as always, exposed yet a new set of limiting criteria
for conquering. That's the way of science and engineering. This advertisement from a 1954 edition of Radio &
Television News featured breakthrough development by
Electric of the 436A vacuum tube for tripling the number of voice calls that could be sent over a single coaxial
for dependable bi-directional transfer of digital data, the
25 Series RF transceiver module is capable of transmitting over distances of up to 1 mile (1.6 km)
line of sight. Operating in the 902 to 928 MHz ISM (Industrial Scientific and Medical) frequency band, the
module is capable of generating +13 dBm into a 50 ohm load and achieves an outstanding typical sensitivity
of –105 dBm. The 25 Series module implements a Frequency Hopping Spread Spectrum (FHSS) protocol along with
networking and assured delivery features.
is a nice quiz on
total equivalent capacitance for circuits containing various combination of series, parallel, and series-parallel
connections. To help in calculation, all of the individual capacitor values are the same. Many of them you can
probably solve in your head, especially if you mentally rearrange the circuit into a more readily recognizable
configuration. For instance, circuit #1 can be redrawn having two parallel branches across the source. One branch
has just a single capacitor while the other has two parallel capacitors in series with one capacitor. The equation
is then C + (2C2/3C) = C + 2/3C = 5/3C. For C = 6 pF,
Ctotal = 5/3*6 pF = 10 pF.
from the Cube is a regular feature run by EDN, in which readers tell tales of interesting experiences in
their engineering careers. This particular story is very interesting and highlights why you should never accept
that a solution to a problem has been found until you fully understand the initial cause. What's really scary
is that evidently this product and its 'cure' are probably still doing active service in airplanes around the
globe. It is hard to believe that a QA department would sign
off on such a deal.
new 868 MHz
NT Series RF transceiver module from Linx makes it simple to send and receive digital data in the 863 to 870 MHz
band. The module offers the option of UART or True Transparency™ interfaces which lets the user create a wireless
wire for use with nonstandard data rates, custom protocols, or encodings such as PWM and Manchester. The module
features best-in-class receive sensitivity (up to −113 dBm) and low power consumption
(only 19.2 mA in receive mode and 16mA in transmit mode at 0 dBm).
has released Version 10.07, the latest update to its
V10 suite of high-frequency design
software tools, inclusive of Microwave Office®/Analog Office® circuit design software and Visual System Simulator™
system design software, as well AXIEM® 3D planar EM software and Analyst™ 3D finite element method EM software.
Hundreds of enhancements, many of them user-requested features, have been made to this latest release, including
significant additions to AWR's unique and powerful EM technologies.
LLC announces the availability of a wideband power amplifier operating from 0.7 - 4.2 GHz. Their new
uses the latest GaN technology to achieve a gain of 46 dB and an exceptional gain flatness of ±1 dB.
This amplifier provides 30 dBm output power in a very small package (6.49 x 2.87 x 1.89 inches).
Microwave is the world's largest manufacturer of electro-mechanical
RF switches. They are AS9100 / ISO-9001 certified and committed to providing unparalleled customer service,
competitive pricing, on-time delivery and switch products that are distinguished by quality and reliability. Dow-Key
offers the largest RF switch product line in the world with over 10,000 unique configurations.
to RF Cafe visitor Niger S., of Herndon, Virginia, for winning the
June Book Drawing. Nigel selected
Handbook of RF, Microwave, and Millimeter-Wave Components. Each month I select someone to receive
a free book from those provided by Artech House or Cambridge University Press. They are often books I have used
to create quizzes. How to enter? Either buy one of my inexpensive
software offerings or send me an e-mail.
I never really thought about the
as a crystal amplifier, but in fact it was fabricated from a crystal of germanium with two 'cat whisker' wires
pressing on its surface. Before the transistor was the simple rectifier made of a crystal of selenium or even
carborundum with a point contact. Those were used for turning AC into DC and for detecting radio wave modulation
envelopes. For a really good synopsis of the early development path of semiconductors, read this story from a
1968 edition of Popular Electronics that commemorated the 20th anniversary of Bardeen, Shockley, and Brattain
announcing their transistor. Having been written much closer to the days of discovery, the story has not been
filtered through as many writers' points of view, and contains some information I'll bet you have never read before.
E.g., did you know that semiconductor dopants were originally referred to as adulterants? Did you know that Shockley's
early research was on field effect devices and, if successful, would had made FETs the first forms of transistors
a recent IEEE Spectrum story titled, "Unclean
at Any Speed," Ozzie Zehner contends based on research that electric cars don't solve the automobile's environmental
problems. After factoring in the big picture from beginning to end of production of the vehicle, its battery pack,
and the charger, the inefficiencies of electric power production and distribution, and battery change-out and
disposal, even reaching break-even is questionable. Mr. Zehner, BTW, is a convert from the
EV church of true believers, having even built
his own e-car decades ago when doing so would more likely elicit strange looks than entranced gazes of fawning
approval. He changed sides after extensive research suggested maybe the numbers were being manipulated in order
to advance an agenda. The impetus to "go green" with autos has more to do with a need to feel good about one's
self than reality. That said, I'd gratefully accept a donation of a
Tesla Roadster any day.
of Reflector Antennas and Feed Systems Volume 3: Applications of Reflectors, by Sudhakar Rao, Lotfollah
Shafai, and Satish K. Sharma. This is the first truly comprehensive and most up-to-date handbook available on modern
reflector antennas and feed sources for diversified space and ground applications. There has never been such an
all-encompassing reflector handbook in print, and no currently available title offers coverage of such recent
research developments. The Handbook consists of three volumes. Volume 3 focuses on the range of reflector antenna
applications, including space, terrestrial, and radar. This book covers recent developments of reflector antennas
used for satellite communications, terrestrial communications, and remote sensing applications.
you one of those people who say you don't mind the government collecting data on you because you've done nothing
wrong? This might change your mind. German politician
Malte Spitz sued Deutsche
Telekom for 6 months of metadata that they
collected from his cellphone usage. A programmer used it to create a real-time, animated map of how the reporter's
movements were tracked within and between cities, how long he was at each location, and with whom he was communicating.
His phone-based Internet surfing was logged. Anyone in Spitz's immediate vicinity (supporters,
business contacts, etc.) would also be known. That was waaaay back in 2009; what do you think Big Bro knows
by now? Are you absolutely sure your history will never be misinterpreted or - indulge the conspiracy theorist
in me - manipulated at the government's convenience?
Cafe advertiser Electro-Photonics
offers a free TRL calculator. "TRL (Thru, Reflect, Line) remains one of the most
popular alternative calibration methods for measuring non-coaxial devices to the traditional short, open, load,
and thru (SOLT), two-port error correction calibration method.
TRL calibration is based upon an 8-term error model and
uses three standards - thru connection, high reflectivity termination, and a section of uniform line
(λ/4 longer than the thru line at the center frequency). The electrical length of
the line is determined during the calibration and does not need to be known. The characteristic impedance, Z0
of the delay line is the only critical parameter."
sleep that shuns my restless bed | Returns to haunt my desk instead." - Frank R. Canning, July 8, 1950 Saturday
Evening Post. Can you relate to that?
from shortwave (SW) station
based in Okeechobee, Florida, ended today, June 30, 2013, after nearly 35 years of continuous operation. Prior
to the advent of the Internet, cellphone, and WiFi services, SW radios were the only means of receiving information
in the nether regions of the earth where war and Communism denied people access to information that might contradict
the strict dictates of iron-fisted regimes. As with so many other groundbreaking technologies of yesteryear, shortwave
broadcast stations are rapidly disappearing because costs are prohibitive. If you click on the thumbnail above,
you will see many cool photos of the
WYFR station equipment room and antenna field that included
14 transmitters and 23 antennas directed toward various
parts of the world. It's kind of sad, but I had to laugh at this line from one article on the sign-off, "Family
Radio has been struggling ever since the world did not end as predicted in 2011."