was founded by Engineers for Engineers. Amplical is determined to be 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. Our products
are typically available from stock.
The world's first
electric wristwatch went on sale on January 3, 1957 - the
Ventura model, by Hamilton Electric, and it retailed for $200. I use the event as
the theme of the RF Cafe logo for that day in history. Unlike today's electric watches
which use a crystal for timing, the early watches used a pulsed motor to energize
the balance wheel coil, in place of a mainspring and an escapement mechanism. The
watch shown in this article from the February 1958 edition of radio-electronics
is a model 500, which you can find more detail about on the Unique Watch Guide website.
Telit Wireless Solutions, a global provider of
high-quality M2M solutions, products and services and Parsec Technologies, a global
supplier of advanced amplifier technology communications products, solutions, and
services, today announced that a combination of the companies' technologies results
in the world's lowest profile companion solution for GPS receiver and antenna. For
host devices able to accommodate higher volumetric symmetry, assembly of the components
can be made to fit a 6x16x8 mm volume. Along with class leading miniaturization,
the receiver outperforms top traditional designs
Echo 1 was
put into orbit on August 12, 1960. This article was written 2½ years earlier in
1958 by Radio-Electronics editor Hugo Gernsback. A technology visionary and prolific
inventor and writer, Mr. Gernsback astutely outlined the vast number of advantages
that had already been and would in the future be afforded the science community
by virtue of a satellite's perspective from space. Two of the Soviet Union's Sputnik
satellites had revealed the surprisingly irregular shape and gravitational influence
of the Earth, information about the upper atmosphere, and aspects of
space environment effects on radio communications. America was
scrambling to catch up. Gernsback and others postulated the configuration of active
relay transceivers powered by solar cells and storage...
Backed by decades of experience in the design
of Noise Sources and Instrumentation for telecommunications, Noisewave is a complete
supplier of specialty
Components and Test Equipment. Noise is our focus, our business, so we can help
yours. We provide our customers with high quality standard and custom noise test
solutions to meet commercial and military wireless applications.
Mason often used two precisely timed tactics to wrap up his courtroom cases. The
first was asking the sworn party on the stand something like, "What if I told you
we found the knife you threw away and Forensics lifted your fingerprints off it?"
Said perp's council and the spectators would gasp in amazement and the murderer
would subsequently offer a full confession, then ask Mr. Mason how he found the
knife. "I never said we found the knife, I said 'what IF I told you we found the
knife?'" The second tactic was making inadmissible statements for the jury to hear,
knowing that the judge would instruct them to disregard it. As Robert Ambrogi states
in this article titled, "Excluding Expert Testimony the Jury Already Heard...
Electronics has released new designs for a 729 MHz LC bandpass filter, an 800 /
1600 / 2400 MHz triplexer filter, and a 813/858 MHz PTT SAW duplexer filter. All
can be ordered directly through their AMCrf
following paper titled "The Design of Ultra Narrow-band Amplifiers Using Small Signal Varactor
Up-converters for ESM, ECM, ECCM, and ELINT Applications" was submitted for
publication by Planar Monolithics Industries, Inc. (PMI), and has been duly
accepted by the Technical Committee and Management of EWCI-2014. The full text of
the paper can be found here on
RF Cafe or on the
blast from the past, I just found an advertisement by Bell Telephone Laboratories
"Twistor" memory in a 1958 edition of Radio-Electronics. According
to Bell, their radically new "Twistor" magnetic memory matrix was vastly superior
to conventional ferrite core memories. It used hair-thin magnetic wires (more like
a flattened tape) interwoven with equally thin copper wires to store and read out
ones and zeroes. Doing so reduced manufacturing costs, by eliminating the relatively
expensive ferrite cores and eliminating the difficult job of threading the read,
write, and sense wires through the core centers. Twistor memory also required less
current to operate, was denser, and weighed less than core memory. Within a decade
CMOS RAM was available to replace the magnetic memory, but from a reliability standpoint...
NuWaves Engineering, an international radio frequency
(RF) and embedded systems solutions provider, announced today that the company has
added AeroGear Telemetry, Inc. as an authorized representative of its products and
design services for the Mid-Atlantic, Southeast and South Central regions of the
U.S., in total covering 17
states as well as the District of Columbia. With over 100 years of combined sales
experience serving the Military, Aerospace, and Government market sectors, AeroGear
provides expertise with telemetry, instrumentation, and surveillance & reconnaissance
communication electronics solutions. "NuWaves' sales and support footprint has grown
Journal, an industry leading Horizon House technical publication, has released the
industry's first interactive
technical magazine that uses the augmented reality app Layar to overlay digital
information onto the pages. When readers scan the pages that are marked with the
"Scan page using Layar app" logo with their mobile device, digital information is
overlaid onto the print page. Readers will be able to experience more engaging rich
media delivered automatically and can tap the screen to view other related information.
Videos and animations appear to "play out of the page" in the augmented reality
We all have pet peeves, which begs the
question, "What is yours?" One of my pet peeves is the nearly universal misuse of
the phrase "begs the question." As presented in the first sentence, the usage is
utterly incorrect. To "beg the question" does not mean a question is begging to
be asked. Rather, it describes the occasion of a self-proving statement, a logical
fallacy or circular reasoning. Grammarians refer to the transgression as "BTQ Abuse." Supposedly, the original
derivation is from the Latin term "petitio principii," meaning to petition the principle,
or to challenge the assertion of a statement. For example, if I say, "ABC Corporation's
receivers are superior to XYZ Corporation's inferior receivers," I have begged the
Receiver Technology: Principles, Architectures and Applications, by Ralf Rudersdorfer.
Basic principles and theories of present-day communications receiver technology
presenting realization concepts at the system level, taking into consideration the
various types of users. Details of the circuitry are described providing the reader
with an understanding of fully digitized radio receivers, offering an insight into
the state-of-the-art. The author outlines fields of applications and their features
and considers the specialty of high-quality radio receivers. They are typically
used for radio surveillance, signal intelligence, modern radio bearing and at the
classical radio services and describes the entire range of parameters that are useful
for the characterization of these receivers.
The more things change,
the more they remain the same. People (including, admittedly, me) don't want to
have to pay for any type of media delivery, especially when it arrives via air waves
or the Internet. We expect to pay for print media like books, newspapers, and magazines...
unless they are available online, in which case they should be free. Six months
before I was born, a reader of Radio-Electronics magazine wrote to declare
his outrage at the fledgling industry of
Pay Television. That a viewer would be expected to pay the broadcaster
for a show that was being, in his opinion, amply subsidized by advertisers, was
an outrageous concept, an unthinkable assault on all that is holy. While his indignation
was probably shared by the majority of the television viewing public, evidently
the maniacal scheme succeeded...
Crooks sent me an e-mail alerting me to a free* distributed element filter program
he just released called "FilterDE."
It was designed to assist in the development of distributed element RF microwave
filters, consisting of series and open shunt transmission line elements for low
pass filters, or parallel coupled lines for band pass filters. For low pass filters,
FilterDE uses an iterative optimizer, enabling the user to design a filter by specifying
the desired performance of the filter and the number of poles. For band pass filters,
it uses edge coupled filters based on Chebyshev polynomials. FilterDE uses ideal,
loss-less models for distributed elements. This means that there will be higher
insertion loss and more rounded transition regions." I downloaded and ran FilterDE
and entered parameters...
Triad RF Systems, was formed in 2010 with
the objective to solve the problem of high power amplifiers (HPAs) being the Achilles
heel in most RF radios. We have solutions for integrating high performance HPAs
into sophisticated RF
subsystems and systems without sacrificing
efficiency and linearity. Triad RF Systems serves all areas of the RF and Microwave
industries including military, satellite and commercial communications. Our products
operate from 10 MHz to 20 GHz.
The barman says, "We don't serve
faster-than-light particles here." A tachyon enters a bar. - Anon. Ok, so
it's not really a quote, but put it on the cover of your next presentation for a
Aliens sculpt crop circles with regularity on
the country sides of England, so the appearance of this 310-foot pattern carved
into a barley field in California left the locals wondering if ET and his gang were
broadening their "hood" by tagging spots in the U.S. As it turns out, the spectacle
of agricultural art was the
handiwork of the NVIDIA company, done as a promotional scheme to draw (cut, actually)
attention to their newest über video microprocessor chip. Sporting 192 processor
cores, the Tegra K1 claims,
"the chip would make for a tablet more powerful than an Xbox 360 or PlayStation
3 game console, while consuming one-twentieth the power." Those little depressions
in the center of the IC are the Braille form of the number 192. GPS-equipped tractors
are able to create patterns with amazing accuracy, but in this case...
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 designers. Enjoy.
KR Electronics invites visitors to explore its
new website at www.krfilters.com. The
new website is designed with improved navigation and functionality. Customers can
access data sheets for nearly one thousand previously designed filters or request
a custom filter online. Please visit our new site and give us your feedback using
the customer feedback form. Providing custom and standard innovative filter solutions
for both the commercial and military markets for over 40 years.
is the very first episode of the "Carl & Jerry" series that ran for many years in Popular
Electronics magazine. In the manner of The Hardy Boys, Nancy Drew, et al, Carl
and Jerry are two teenage boys who, in their pursuit of their electronics hobby,
manage to get themselves involved in crime scene investigations, in odd situations
with friends and adults, and even while horsing around in their basement laboratory.
Amateur radio was a key feature of many of their adventures. John T. Frye authored
every adventure as he developed his sleuthing buddies over time to go from a frumpy
Jerry Bishop with a "well-padded frame" and a Farside-esque bespectacled Carl Anderson
to a couple more stealthy, professional looking investigators who sometimes employed
everything RF has published a list
of most popular on its website in 2013. Categories include RF / microwave components,
news stories, test equipment, and white papers.
There are currently 129,148 RF & Microwave Products from over 318 Companies
listed in 217 Categories listed in the
RF & Microwave Company Directory
on everything RF.
National Company of Cambridge, Massachusetts, was one of the first
large distributors of electronics components and appliances. Believe it or not,
National began life as the National Toy Company. Thanks to the efforts of Mr. James
Millen, W1HRX, in designing and marketing high quality radio products, the company
evolved into a favorite source by both amateur radio operators and casual listeners
of shortwave radios. The NC80X covered the commercial broadcast band and a couple
shortwave bands, whereas the NC81X covered only multiple shortwave bands for amateur
this article discusses audio waveform measurements, the lesson learned applies equally
well to any waveform frequency. In the RF realm, we are accustomed to injecting
two sinewaves at equal amplitudes into a unit under test (UUT) and reading the relative
output powers of the two input signals and the
n-order intermodulation signals. It is usually a very simple test
with simple to interpret results handily shown on the display of a spectrum analyzer.
The task is made a bit more difficult when injecting signals of unequal strengths
and especially when measuring in units of voltage as a viewed on an oscilloscope
display. I dare say most of us need to do some head scratching and looking up of
formulas to pull off such a measurement.
PMI's 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 from DC to 40 GHz.
Recently, I commented
on the behind-the-scenes efforts by many people that go into developing products
which eventually become ubiquitous in our everyday world. Just like looking up the
answer to an end of the chapter problem in the back of a textbook, the result often
seems so obvious that you wonder why it wasn't apparent to begin with. The newest
Sherlock Ohms is a great illustration of the point. This anecdote
by A. David Boccuti is a prime example of dedication to finding cost-effective solutions
to manufacturing challenges. Having worked in concert with many mechanical engineers
over the years, I have amassed a lot of respect for the ingenuity exhibited by my
fellow product development travelers. In the 'old days,' while under the employment
of defense contractors, price...
API Technologies Corp., a leading provider of
high performance RF/microwave, power, and security solutions for critical and high-reliability
applications, is now offering a
that includes an integrated LNA. Designed for radar, EW and ELINT applications,
this new multiplexer provides excellent broadband performance across the 2 GHz
to 18 GHz range using suspended substrate stripline (SSS) technology. Specifically
suited for agile receiver front ends and directional finding systems, API’s switched
multiplexer provides a 20 dB gain with a 5 dB noise figure and fast switching
at 100 ns
for some employment news, I ran across a U.S. Bureau of Labor Statistics web page
that gave median
annual salaries for engineers and technicians in 2012. I doubt the numbers moved
much in 2013. Median is the point where half the samples are less than and half
the samples are greater than that median number. Personally, I prefer a mean average
number along with a standard deviation. The problem with a median value is that
it is possible (albeit not necessarily probable) that the lower half values all
lie within, say, 2% below the median, while the upper half values lie 200% above
the median. In such a situation the mean average of the sample would be almost 100%
(2x) the median and the standard deviation, and the standard deviation would be
nearly equal to the median. For example this set of sample data produces the following
statistical numbers values...
If you appreciate good humor,
then you'll appreciate these comics from the January 1958 edition of Radio-Electronics.
Their themes are representative of situations common in the era - like TV repairman
woes and men obsessed over electronics gadgets while ignoring their wives. Not that
there are ever any comics in today's electronics magazines, but if there were, they
likely would poke fun at Oblivion texters and depict fathers being made to look
like fools by their disrespectful kids for not knowing how to program a Roku player.
"Rediscovery of FM Broadcasting" could be a contemporary headline.
The decline of broadcast radio has been a major concern of station owners for well
over a decade since Internet and satellite radio has dominated the venue through
which listeners access radio stations. Local broadcasters have long aired syndicated
programs that include national advertising, but the money to pay for those segments
came from revenue supplied largely by local companies. FM broadcasting began commercially
around 1945 in the familiar 88-108 MHz band yielded by the military after World
War II, and grew in number of stations very rapidly in the first few years.
Then, it began a decline for a few more years until finally leveling off after...
visitor Cornell D. sent me an e-mail about a website called Iowa Hills Software.
Per the site's tag line, "The
analog and digital filter design programs on this site are free.
This web site, and the programs on it, are a retired RF engineer's winter time hobby."
If your primary interest is in calculating theoretical values for filters and not
being able to simulate "real world" effects of component geometry and materials,
packaging, and circuit boards, then it would be hard to find a more comprehensive
program for investigating the potential for filter designs. However, the software
goes beyond presenting only the canonical form (basic) of the circuits because,
particularly for bandpass and bandstop filters, it is often difficult or impossible
to realize with actual components
Semiconductor Engineering, by Bo Lojek. This book provides a unique account
of the history of integrated circuit, the microelectronics industry and the people
involved in the development of transistor and integrated circuit. In this richly
illustrated account the author argues that the group of inventors was much larger
than originally thought. This is a personal recollection providing the first comprehensive
behind-the-scenes account of the history of the integrated circuit.
so many things in life that we take for granted - aspirin, automatic clothes washers,
drill motors and bits, eyeglasses, rifles, bicycles, transistors, to name a few
- we rarely think about the effort that went behind the end product that is now
enjoyed. Even relatively simple devices like scissors are the result of someone
saying to himself or herself, "Self, I need something to make cutting fabric and
paper and hair simpler and neater, so what might that thing look like?" Then, after
making a working prototype, improvements are made based on empirical testing from
usage, improvements are made in the form factor, materials, size, etc., until evolution
results in what can be purchased today. If you have ever been in a product design
cycle, either privately or corporately, then you know the process well. A concept
as sophisticated as
developing television is much more involved than developing...
radio station operators seemed to always be amongst the first to lose their rights
in time of war. Governmental power brokers - from unelected local bureaucrats on
up to presidents - love to demonstrate their influence over citizens when the opportunity
Radio Act of 1912 revoked the rights of amateur radio stations
to operate, and in some cases authorized the confiscation of radio equipment for
use by the government. Permission was not restored until 1919, after World War I.
Amateurs took it on the chin again in World War II with revocation of licenses.
In this 1917 article in The Electrical Experimenter publisher Hugo Gernsback
makes the case for permitting "our red-blooded boys be trusted to assist our officials
in running down spies" "...we realize how absurd it is to close all privately owned
radio stations during the war," says he. It fell on deaf ears...
"Long live the amateur, long live wireless!" - Opening sentence
in opening article in first edition of Hugo Gernsback's new
The Electrical Experimenter magazine (May 1913). Gernsback was an indefatigable
pioneer electrical and electronics inventor, publisher of many electronics magazines,
and founder of the Wireless Association of America.
amplifiers (aka "mag amps") use a property of saturated core inductors (saturable
reactors) to obtain signal amplification via a transformer-type plus diode-assisted
Magnetic amplifiers were preferred over vacuum tube amplifiers
in some circuits because they do not require a high bias voltage, are generally
smaller in size, are quite robust and are practically immune to microphonics. Their
biggest limitation is bandwidth. The high number of turns in the core provides a
lot of interwinding capacitance so the self-resonant frequency is in the low megahertz
range. Additionally, the need for the magnetic amplifier reactor to operate in a
saturated condition further imposed a limit on the frequency response. Even today,
there are some critical applications that exploit the fool-proof and ultra high
reliability nature of the magnetic amplifier. This article goes into the details
of operation both as amplifiers and as bistable multivibrators.
last week, 2014's first
RF & Microwave Crossword Puzzle is pretty big. With about
220 words that are all hand-selected to be technically oriented, this is one of
the bigger formats I use. Software does all the hard word of making everything fit,
but I design the grid and have built the word-clue dictionary from scratch over
the course of 10 years. Your company's name might even appear one day.
DongJin Technology Innovation has published a
new pamphlet detailing a line of RF power divider
/ combiners with operational frequencies ranging from 10 MHz through 2700 MHz
and power handling as high as 20 W. Small sizes make them ideal for mobile
communications equipment applications. All feature low insertion loss, low VSWR,
high isolation, aluminum bodies, compact size. Specifications can be customized
for your application. SMA / N connector types are available.
RF Cafe supporter since 2010, develops both turnkey and custom solutions for the
RF telecom equipment designers and manufacturers. Currently,
our product line includes
high power couplers, splitters / combiners and
filters between 1 MHz and 3 GHz. We have a tight relationship with
a local, ISO certified manufacturer with a 25 000 sq. ft. facility and more than
20 years experience in the RF/microwave design and manufacture. This gives us the
best of both worlds, the agility of a small company and the production capabilities
of a larger-sized, high-volume manufacture.
Class-B push-pull amplifiers has not changed since 1960 when this
article appeared in Electronics World. The transistors for making them
have improved in most cases, but the design procedures are basically the same. Class-B
amplifiers, in case you are not familiar with the topology, are able to amplify
zero-referenced sinusoidal signals throughout the full 360 degrees of rotation signals
without an offset voltage bias; they are constructed from two Class-A amplifiers
in a cascode configuration. Issues like crossover distortion and thermal runaway
are discussed in the amplifier design procedure.
RF Cafe visitor
Steve G. just sent me a link to the
Gutenberg website where you can download copyright-free books and other material
on a broad range of subjects. The particular page he sent me to is for books with
"radio" in the subject. There are currently more than 44,000 titles from which to
choose, and many of them are available in multiple file formats like HTML, Kindle,
EPUB, and Plucker. Although most date back quite a few decades, there are more contemporary
titles whose authors placed them in the public domain for free, legal access. If
you are a fan of the
Carl & Jerry adventure series from Popular Electronics, then
you might enjoy The Radio Boys and Astounding Stories of Super Science. If
you like historical books on technology, maybe Project Trinity 1945-1946
would be of interest; interestingly, the opening page of the book reads, "Destroy
this report when it is no longer..."
PMI Model No. SDLVA-218-44-70M is a
Video Amplifier (DLVA) designed to operate over the 2.0 to 18.0 GHz frequency
range. This model offers a logging range of -40 to +4 dBm having a log slope
of 70 mV/dB. The logging linearity is better than ±0.75 dB and the rise
time is 25 nsec maximum and the fall time 300 nsec maximum. This model
operates on ±15 VDC.
Guided Wave Technology's
Coupling 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 transmission zeroes, complex
transmission zeroes, extended parameter plotting options, S-parameter file (s2p)
generation, topology matrix definition of filter circuits & much more.
You do know that your E-ZPass™ is getting
read all over town, don't you? If you have one of the devices hanging from your
sun visor and think that the only thing tracking your location is the tool booth
plaza on the thruway, you might be in for a big surprise once you build this
E-ZHack circuit for your E-ZPass™.
As presented in the January 2014 edition, this modification will sound an audible
alarm when the circuit detects that your E-ZPass™ is being read. Per the article,
"E-ZPass™ is a device that drivers can buy in 15 states to zip through tollbooths
across the country, usually without stopping. More than 24 million tags - and growing
- exist in the U.S. alone. Each 'listens' for a wireless signal broadcast by an
electronic reader. When that signal is strong enough, a tag draws power from an
onboard battery to broadcast its serial number back to the reader. The reader then
relays the information to a computer server to bill the customer linked to the tag.
Unbeknownst to most E-ZPass™ users...
entry by Linx Technologies' Aaron Croslow provides a good introduction to the world's
various satellite navigation systems in operation and/or in planning and/or building
stages. The U.S. activated our Global Positioning System back in the early 1990s
as the world's first such constellation of satellites. Since then, Russia deployed
its GLONASS system, the EU is on the verge of launching Galileo, and China is working
on its BeiDou Satellite Navigation System (BDS - aka Compass). Linx, as with many
GPS receiver manufacturers, is in the process of providing modules that work well
with multiple systems.
is an RF and microwave connector, cable, cable assembly and passive components -
fixed attenuators, matching pads, dividers / combiners, DC
blocks, feedthrough & high power terminations,
dipole antennas - manufacturer. Synergies and large stock keep lead times to a minimum
and allow us to offer customers an unparalleled flexibility. Innovation is pivotal
and we are constantly developing new products.
This quiz is based
on the information presented in
Make Your Own Tube Testers
and Electron Tube Equipment, by Gary Steinbaugh. With more than 30 years
of RF engineering experience and Ham radio involvement, Gary has a very broad and
deep proficiency in electronics. His new book, Make Your Own Tube Testers and
Electron Tube Equipment, is a great assimilation of his personal knowledge
and includes some of the highest quality line drawings and photographs of any technical
book I have ever seen - and I've seen a lot of them! The preface section is also
unique in nature, followed by a short history of and basic circuit design principles
for vacuum tubes. Gary also conceived of and built a 3-dimensional physical model
of the plate, transfer, and constant current characteristic curves for a typical
vacuum tube (6SN7); you've never seen...