For a few years, each month's edition
of Radio-Electronics magazine included a column entitled "The Radio Month,"
which was a collection of a dozen or so relevant news items. The March 1953 issue
reported on transistorized hearing aids (those old vacuum tube types didn't fit
in your ear very well), how the number of TV sets in the U.S. had out-paced the
number of telephones thanks to new UHF channels, the continued rapid expansion of
television in Europe, and the upcoming 1953 I.R.E. Show (Institute of Radio Engineers)
in New York City. Of particular note was the new germanium ore source discovered
in Kentucky - not the first place I think of with a semiconductor mother lode. At
germanium (Ge) was still the primary element used in transistors and diodes,
although silicon was making rapid inroads. The story was germanium sold for $350
per pound in pure metallic form...
science effort to explore if disturbances on earth can be sensed throughout the
atmosphere. Sensors are usually thought of in terms of physical devices that receive
and respond to electromagnetic signals - from everyday sensors in our smartphones
and connected home appliances to more advanced sensors in buildings, cars, airplanes
and spacecraft. No physical sensor or aggregation of electronic sensors, however,
can continuously and globally detect disturbances that take place on or above the
earth's surface. But the physical
atmosphere itself may
offer such a sensing capability, if it can be understood and tapped into. To that
end, DARPA recently announced its Atmosphere as a Sensor (AtmoSense) program, whose
goal is to understand the fundamentals of energy propagation from the ground..."
RF Cafe visitor Kevin A., of Roanoke,
VA, sent me this article from the September 1972 edition of the American Radio Relay
League's QST magazine. He was motivated to send it after reading some of
the articles I posted from WWII era QSTs. We can all probably relate a
story similar to the one told here. How many "Old Al" types - the
antithesis of an "Elmer"
- are out there who knowingly or unknowingly frustrate others from participating
in an otherwise fun activity because he insists on beating up on a trivial topic
ad nauseam? You can feel the angst in the author's voice while reading. Ray, are
you out there? Is this story real or fictitious? It could easily be either...
Copper Mountain Technologies (CMT) created
RF Fundamentals resource website with content for beginner engineers or
people without an RF Engineering background. CMT has generated a large number of
videos and application notes and consolidated them on a dedicated website. The Vector
Network Analyzer (VNA) Basics area includes topics like "What is a Smith Chart?,"
"Getting Started with a VNA: Top 10 Tips and Tricks," and "What are S-Parameters?"
App Notes features titles like "Why USB Vector Network Analyzers?," "What Makes
a Good VNA?," and "Calibration Types and Considerations for VNAs." Making Measurements
offers "Time Domain Analysis with a VNA," "Fixture Removal from VNA Measurements,"
and more. The new RF Fundaments website will grow over time...
RF Cafe typically receives 8,000-15,000
website visits each weekday and about half that on weekends.
RF Cafe is a favorite of engineers, technicians, hobbyists, and students all
over the world. With more than 8,000 pages in the Google search index,
RF Cafe returns in favorable
positions on many types of key searches, both for text and images. New content
is added on a daily basis, which keeps the major search engines interested enough
to spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. I also re-broadcast homepage
items on LinkedIn, Facebook, and Twitter. If you need your company news to be seen,
RF Cafe is the place to be. Advertising
begins at $45/month.
always been something nifty keen about colorized gradient maps be they thermal,
electric or magnetic field, mechanical stress, etc. Bill Schweber has a good article
on the EDN website entitled, "Forced
Air Cooling vs. Wind Chill: Same Principle, Different Reality." He begins, "Forced-air
convection cooling via fans is a widely used approach for keeping the temperature
of electronics below some threshold value. It's more aggressive than 'natural' convection
cooling and ensures that air flows across the electronics and heat is removed (ensuring
that the heat has a place called 'away' to go to [excellent line! -KRB],
that's another story and challenge). While engineers might prefer natural, unforced
convection cooling to avoid the perceived negatives of fans (cost, noise, reliability,
space, to cite a few), the reality is that the available airflow mass and rate in
many unforced cases is either inadequate or unreliable, so fans must be used. The
obvious question is, 'How much airflow do I need?,' followed quickly..."
Electro-Photonics is a global supplier of
RF & Microwave components.
Their products include SMT hybrid and directional couplers, wire bondable passive
components, mounting tabs, filters, transmission lines, and very useful test boards
for evaluating components (spiral inductors, single-layer capacitors). The Electro-Photonics
team can support your small R&D design requirements with RF & Microwave
test fixtures and save you valuable design and characterization time. Please take
a moment to visit Electro-Photonics' website and see how your project might benefit.
After discussing the virtue of not letting
someone else's opinion on the likely cause of a problem direct your own actions
when troubleshooting, service shop proprietor Mac McGregor asks Barney about issues
he has run into related to the area's having recently had television channel 13
broadcasting added to the area. When he mentions the trouble cause by homeowners
leaving excess lengths of
twin-lead 300 Ω lead−in wire coiled up behind the TV set, it brought to
mind my own mentioning a couple days ago that very scenario in comments made on
the "A Two-Band Piece of Wire" article. You and I would be tempted to criticize
people for making such an "obvious" mistake, but most people then - and now - have
no knowledge of the particulars of routing such cable. A switchover to coaxial cable
with the advent of cable TV removed most of the need for being concerned over installation,
other than assuring tight connects, proper terminations, and keeping cable length
as short as possible to minimize signal loss. Other than that, properly shielded...
Fairview Microwave, an Infinite Electronics
brand and a leading provider of on-demand RF, microwave and millimeter wave components,
has released a new series of
Class AB broadband high power amplifier modules that incorporate GaN, LDMOS
or VDMOS semiconductor technology. Fairview's comprehensive new line of class AB
broadband high power amplifiers consists of 18 new models spanning frequency bands
from 20 MHz to 18 GHz. These designs are unconditionally stable and operate
in a 50 ohm environment. They offer power gain up to 53 dB and saturated
output power levels from 10 watts to 200 watts. This line includes 2 new
heatsink modules with DC controlled cooling fans specifically designed for the 18
new models to ensure optimum baseplate temperature for highly reliable performance..."
It's not often that you will see a full-page
ad promoting a particular element in the periodic table, but in 1950 that wasn't
the case. This advertisement for
Anaconda Copper Mining Company which appeared in a 1950 issue of The Saturday
Evening Post magazine extolled the virtues of element number 29 - copper (Cu , from
the Latin "cuprum"). Aluminum and iron were other popular topics of advertising.
If you do a search on the history of Anaconda, which is today owned by the Atlantic
Richfield Company (ARCO), what dominates is the harm done to workers and to the
environment. The short video below is one of the less vicious reports on the company's
operations in Butte, Montana and in Chile. COPPER... Time's Friendly Enemy Time
and copper get along well together - because of one simple reason: Copper chooses
to ignore time completely. For nature has given copper the great quality of almost
eternal youth - the ability to resist the slow but steady ravages of the elements,
for centuries if need be...
"The future of space exploration might be
tiny satellites that can fit in the palm of your hand. Space exploration has
infatuated generations for decades now. What started as a race to master human achievement
between superpowers has evolved into a human endeavor concerned with the future
of humanity. For what is essentially the entire history of human space exploration,
the process has necessitated one thing: money. The economics of space When the shuttle
program was in full force between running launches between 1981 and 2011, the average
cost of sending one pound of material into space ran about $10,000 by conservative
estimates, according to Business Insider. Ever since, the space race has largely
turned private, and with this shift, competition is driving that cost per pound
Skyworks is pleased to introduce SKY85333−11
(2.4 GHz) and SKY85747−11 (5 GHz) – two new
front-end modules (FEMs) in our portfolio of solutions designed for high-power
Wi-Fi 6 (802.11ax) applications and systems. These highly integrated FEMs incorporate
switching, low-noise amplifier (LNA) with bypass and power amplifier (PA) for devices
such as networking and WLAN-enabled wireless video streaming systems. Both devices
feature very low EVM floor with 1024 QAM signal which improves throughput and meets
requirements for MU-MIMO operation. The modules offer extremely high linear output
power – up to regulation limits for improving coverage range. The SKY85333−11 and
SKY85747−11 are available now in a compact LGA (24-pin, 3 x 5 mm) package and support
leading reference designs...
Mr. Bob Zollo, Solution Architect at Keysight
Technologies, posted an article on the Electronic Design website entitled "Demystifying
Electronic Calibration," which, among other things, reminds readers that modern
high power voltage and current sources are capable of being re-calibrated in-situ
without the need to remove test equipment from the setup in order to access potentiometer.
It's all done electronically nowadays. Calibration tables are generated and stored
internally in nonvolatile RAM. Ambient temperature variations and response to various
level of load can be compensated in many cases...
MPDevice (MPD) has become a trustworthy
and reliable company in the global RF market as a manufacturer of
passive RF Devices. Included
are attenuators and terminations, coaxial connectors, adapters, and cable assemblies,
DC blocks, surge arrestors, power combiner / dividers, and directional couplers.
The Korean Telecommunication market is now entering into the era of hyperconnected
society. With continuous enhancement in R&D capabilities and quality control,
MPD will continue in an effort to become the No. 1 technologically innovative
company with a focus on the emerging 5G marketplace.
This is another of the articles written
Lee de Forest that appeared in the January 1947 issue of Radio-Craft
magazine, in celebration of the 40-year anniversary since the industry-changing
Audio vacuum tube was invented. Author George H. Clark, a member of the first "radio-man"
to be graduated from the Massachusetts of Technology (MIT), was, in addition to
working for Marconi Wireless Telegraph Company, RCA, and the Telegraph and Telephone
Company, the U.S. Navy's "Sub-inspector of Wireless Telegraph Stations." He dealt
extensively with de Forest regarding installation and operation of radio systems
both on ships and on shore. Interestingly, he mentions that the first Audions were
used as detectors more so than as signal amplifiers, which in fact was de Forest's
original goal (a more sensitive detector) in his experimentation...
ThinkRF Corporation, the leader in
software-defined spectrum analysis, today announced a fully integrated wireless
network testing system with CelPlan Technologies, Inc. The solution allows RF engineers
to conduct drive tests and evaluate network performance, map coverage, or identify
Citizens Broadband Radio Service (CBRS), a new network standard which leverages
the previously underutilized 3.5 GHz spectrum range for shared public use in
commercial wireless services. With the high-performance ThinkRF Spectrum Analyzer
as the scanning receiver and leading drive test software from CelPlan, the solution
offers the highest frequency range in the smallest form factor, with 100 MHz
dispute about the relative quality of vacuum tube versus solid state electric guitar
amplifiers has been ongoing since the dawn of transistors. Tube amp loyalists claim
that a vibrato-like quality is imparted to audio by the microscopic mechanical vibrations
in the metal components that make up the cathode, screen grid, and plate elements.
An RF Cafe visitor sent me a hyperlink to a piece entitled "Best Tube Amps for Electric
Guitar," on the Beginner Guitar HQ website with a rather extensive treatise
on the subject. It of course favors the vacuum tube amplifier for the reason stated.
Here is a report on
blind and double-blind tests that have been conducted in an attempt to scientifically
determine a result. The jury is still out on this one...
Here is an interesting article on the EDN website
by Bill Schweber entitled, "Minimizing
Power-Supply Voltage Drop on PCBs." He discusses the importance of managing
PCB trace resistance to facilitate the high-current, low-voltage typical of today's
layouts. "Despite the widespread availability and use of low-power components, today's
printed circuit boards (PCBs) can require a significant amount of current, with
boards drawing 50, 100, and even 200 A in common use. Whenever current is delivered
to a load, there will be IR-based voltage drop, and designers must take this loss
into account when laying out the board and placing the supply, dc supply rails,
Exodus Advanced Communications is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Power amplifiers ranging
from 10 kHz to 51 GHz with various output power levels and noise figure
ranges, we fully support custom designs and manufacturing requirements for both
small and large volume levels. decades of combined experience in the RF field for
numerous applications including military jamming, communications, radar, EMI/EMC
and various commercial projects with all designing and manufacturing of our HPA,
MPA, and LNA products in-house.
Here is a handy-dandy baker's dozen of 'kinks,'
otherwise known as
tricks of the trade, shortcuts, or clever ideas, that could prove useful while
working in the lab at work or in your shop at home. One suggestion is to place a
sheet of tracing paper over your schematic while wiring a circuit and draw each
connection as it is completed, rather than mark up the original drawing. That was
definitely good for a time when making a spare copy of a magazine page or assembly
instruction from a kit was not as simple a matter as it is today. Whether it be
a schematic or a set of plans for a model airplane, I always make a copy to work
and draw notes on rather than defacing the original...
"Scientists at the Tokyo Institute of Technology
and Socionext have designed the world's smallest
all-digital phase-locked loop (PLL). PLLs are critical clocking circuits in
virtually all digital applications, and reducing their size and improving their
performance is a necessary step to enabling the development of next-generation technologies.
New or improved technologies, such as artificial intelligence, 5G cellular communications,
and the Internet-of-Things, are expected to bring revolutionary changes in society.
But for that to happen, high-performance system-on-a-chip (SoC) devices are indispensable.
A core building block of SoC devices is the phase-locked loop (PLL), a circuit that
synchronizes with the frequency of a reference oscillation and outputs a signal
with the same or higher frequency..."
The ARRL RFI
Book 3rd Edition, written by Mike Gruber (W1RM), will help you to find and resolve
interference. This book covers the causes and cures of many interference problems
that you may experience. Everything from automotive to television, from computers
to DVD players, and audio equipment to telephones can create a problem. The ARRL
RFI Book offers a convenient, step-by-step process to eliminate problematic radio
frequency interference. As technology increases, the likelihood of interference
increases, too. Be ready to battle the noise with The RFI Book 3rd Edition from
The American Radio Relay League.
Goldberg is a familiar name to comic book aficionados for his artistry in Spider
Man, the Incredible Hulk, and the Archie series. QST magazine had him listed
in the "Silent Keys" column in the November 2014 issue because he passed away in
August. A Silent Key, in Hamdom, is usually a title reserved for a deceased licensed
operator (the 'key' reference being a Morse code key), but a search of the Internet
and the FCC license database web page did not turn up a call sign for him. Unless
his record has been dropped from the database, Mr. Goldberg might never have actually
been a Ham, but earned the Silent Key acknowledgement because of his involvement
in a 1986 special edition comic book titled "Archie's Ham Radio Adventure."
It was quite an extensive story that involved all the familiar Archie characters,
and even had a section addressed to parents encouraging them to promote both their
kids' and their own interest in amateur radio as an educational and character building
RF & Microwave 2020 event will be
held on March 18th & 19th at Porte de Versailles, Paris. According to the brochure,
7 good reasons to participate include: "RF & Microwave est le seul rendez-vous
en France pour les domaines des radiofréquences, des hyperfréquences, du wireless,
de la CEM; Vous rencontrez et échangez avec des visiteurs qualifiés; Vous bénéficiez
de l'importante communication du salon: newsletters, catalogue, site internet, et
gagnez en vivibilité; Ce rendez-vous vous permet de gagner un temps précieux..."
Withwave manufactures an extensive line of
metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
fully automated 4-port vector network analyzer
(VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations,
DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures
for calibration and multicoax cable assemblies. Frequency ranges from DC through
110 GHz. Please contact Withwave today to see how they can help your project
Reading this article from a 1950 issue of
Radio & Television News magazine reminds me of a basic truth - at least
for receiving, it is usually possible to realize obtain useful operation with just
any reasonable length of straight wire for an antenna. Transmitting is a different
story since poor VSWR conditions on the antenna connection can damage or cause to
shut down the output stage of an RF power amplifier. Still, if your transmitter
can survive a high VSWR, then chances are you can send out a useful signal. You
won't be breaking any DX records or winning any contests, but you won't be dead
in the water. Surely anyone over 40 years old has jury-rigged an FM radio antenna
out of a length of straight (or bent) wire and/or fashioned a sheet of aluminum
foil around a set-top television antenna to pick up an acceptable signal. In many
cases where the 300 Ω twin-lead cable was improperly snaked along an aluminum
gutter or aluminum siding on a house on its way to the rooftop antenna or had a
long length of excess cable coiled...
If you are an Elon Musk acolyte, which to
a degree, I am, then you might want to plan on attending
Satellite 2020 in Washington, D.C.,
from March 9-12. Mr. Musk, whose enterprises include SpaceX and Tesla, will
be the keynote speaker. The cost of admittance to just the exhibit hall is $99,
and prices go up from there (a la IMS2020).
Sometimes you can find an exhibitor to sponsor your attendance since they are usually
provided with a number of free tickets. Check the exhibitor list and try contacting
someone from a company whose products you use. "SATELLITE's purpose involves cultivating
an environment where the individual AND the collective can thrive. We're very proud
of our international DNA, it's reflective of our belief that we can achieve so much
more when we work together. It may sound cheesy, but breaking the traditional barriers
between people, companies, countries and industries can lead to outcomes that we
never imagined possible when we stay in our silos..."
QST reader Dave Berman, WA2PAY,
wrote in the March 2020 issue's "Letters from Our Members" column about an episode
of the old "Highway Patrol" television show entitled, "Radioactive,"
wherein the ARRL (American Radio Relay League" is mentioned and Ham radio operator
Pat Conway plays a lead role in the show. Broderick Crawford stars as head highway
patrolman Dan Mathews. I did some screen shots of Mel's shack showing the massive
transmitter cabinet and the receiving station desk. On a table across the room is
a Precision Apparatus Co. E-200-C Signal Generator. Do you recognize any of the
other equipment? Note on the chalkboard that the nuclear scientist has beryllium
misspelled as "berilium," unless he happens to be an Indonesian, in which case it's
Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his February newsletter that features
his short op−ed entitled "Dynamic
Spectrum Sharing Coming Next Year," which discusses the quandary the wireless
industry finds itself in with very limited spectrum available in the millimeter-wave
bands that can accommodate high data rates necessary for 5G schemes. I like a statement
made from another source about 5G being the first wireless protocol to perform like
wired connections, but without the wires. Until more spectrum is freed up, some
form of spectrum sharing plan is needed, and service providers are working on what
had been dubbed "dynamic spectrum sharing" (an innovation claimed Ericsson), which
allows available segments of spectrum to be accessed...
"DARPA has selected nine research teams to
develop advanced RF mixed-mode electronics critical to emerging defense applications
in communications, radar, and electronic warfare under the Technologies for Mixed-mode
Ultra Scaled Integrated Circuits (T-MUSIC)
program. T-MUSIC was first announced in January 2019 as a part of the second phase
of DARPA's Electronics Resurgence Initiative (ERI). These RF mixed-mode interfaces
will target the current limitation of in-efficiency of CMOS platforms, where they
are unable to support operations at higher frequencies with larger signal bandwidths.
Today's defense electronics systems rely on radio frequency (RF) mixed-mode electronics..."
With more than 1000
custom-built symbols, this has got to be the most comprehensive set of
Visio Symbols for RF, analog, and digital system and schematic drawings!
Every object has been built to fit proportionally on the provided A-, B- and C-size
drawing page templates (or can use your own). Symbols are provided for equipment
racks and test equipment, system block diagrams, conceptual drawings, and schematics.
Unlike previous versions, these are NOT Stencils, but instead are all contained
on tabbed pages within a single Visio document. That puts everything in front of
you in its full glory. Just copy and paste what you need on your drawing. The file
format is XML so everything plays nicely with Visio 2013 and later...
TotalTemp Technologies has more than 40 years
of combined experience providing thermal platforms.
Thermal Platforms are
available to provide temperatures between −100°C and +200°C for cryogenic cooling,
recirculating circulating coolers, temperature chambers and temperature controllers,
thermal range safety controllers, space simulation chambers, hybrid benchtop chambers,
custom systems and platforms. Manual and automated configurations for laboratory
and production environments. Please contact TotalTemp Technologies today to learn
how they can help your project.
As with my hundreds of previous
science and engineering-themed crossword puzzles, this one for February 23,
2020, contains only clues and terms associated with engineering, science, physical,
astronomy, mathematics, chemistry, etc., which I have built up over nearly two decades.
Many new words and company names have been added that had not even been created
when I started in the year 2002. You will never find a word taxing your knowledge
of a numbnut soap opera star or the name of some obscure village in the Andes mountains.
You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical
location like Tunguska, Russia, for reasons which, if you don't already know, might