RF transmission cable parameter charts are available on the Internet, but what
sets this one apart is that is has entries for some of the popular 300 Ω
twin-lead cables of the rooftop television antenna era. It appeared in a 1956 issue
of Radio & Television News magazine. Mentioned in the article is the
reason most TV lead-in cable was colored brown was to help keep the sun's ultraviolet
rays from penetrating and deteriorating the plastic. Author Robert Gary claims silver
coloring was also used to reflect the UV, but I don't recall ever seeing silver
twin-lead - maybe it was a regional thing like for in the southwest. At the time,
μμfd (micro-microfarad) was commonly used rather than pF (picofarad). He also mentions
the G-Line transmission cable used by many of the
Kazimierz Siwiak and Ulrich L. Rohde have
a great piece in Microwave Journal entitled, "Tuning Electrically Short Antennas for Field Operation."
It sounds like the title of an article you might find in the ARRL's QST magazine,
especially with seeing Mr. Rohde's (a renowned Ham and über RF design
engineer) name associated with it. "Even as the current sun spot cycles do not favor
radio operation in the HF band (defined here as 1.5 to 30 MHz), there are military
and amateur radio applications for 20 W battery-operated radios with whip antennas.
In general, the whip antenna which makes the radio portable is not optimized for
signal propagation: a whip antenna has no ground return or proper counterpoise.
While some users drag a wire up to 8 m behind ..."
Custom MMIC, a leading designer and manufacturer
of high performance
monolithic microwave integrated circuits (MMICs), is excited to introduce four
new MMIC devices to its growing portfolio of standard products that now numbers
over 170. These new products further demonstrate Custom MMICs commitment to continuous
innovation and delivering the highest performing RF and Microwave MMICs in the industry.
Please be sure to visit Custom MMIC at the IMS 2019 show in Boston at Booth # 1350.
I'm not sure when
storytelling as a style of technical writing went the way of vacuum tubes (probably
about the same time, come to think of it), but this article from the January 1958
edition of Radio-Electronics is a prime example of how such prose was utilized.
Two characters, Red and Fuzzball, meet at a coffee counter and discuss the intricacies
of color convergence in color television sets. Such issues are not a concern with
today's electron-beam-less displays, but back in the day, it made the difference
between an acceptable picture and frustrating images with color fringing. Maybe
you remember those days. After having read many articles on troubleshooting, repairing,
and aligning TV sets prior to LCD and LED displays ...
Signal Hound, a developer of highly optimized
RF signal test and measurement, is exhibiting June 4th-6th, 2019 in Boston (Booth
#123) at the IEEE MTT International Microwave Symposium (IMS), the premier annual
international meeting for technologists involved in all aspects of microwave theory
and practice. Signal Hound will be demonstrating their range of products and are
highlighting two new devices - the SM200B 20 GHz spectrum analyzer ($12,300 U.S.
retail) and the VSG60A 6 GHz signal generator ($2,350 U.S. retail). Both products
are scheduled for general availability later this year.
Copper Mountain Technologies
develops innovative and robust RF test and measurement solutions for engineers all
over the world. Copper Mountain's extensive line of unique form factor
Vector Network Analyzers
include an RF measurement module and a software application which runs on any Windows
PC, laptop or tablet, connecting to the measurement hardware via USB interface.
The result is a lower cost, faster, more effective test process that fits into the
modern workspace in lab, production, field and secure testing environments.
When I look at a photograph of ancient buildings,
bridges, and other constructs that required years of planning and labor to complete,
I think of how unfortunate it is that a history of drawings and/or paintings do
not exist that document the construction process that went into it. Other than more
contemporary renditions of what an artist thinks the sites of the Great Pyramids,
the Parthenon, the Great Wall of China, etc., might have looked like as workers
(often slaves) and engineers progressed throughout the projects, very few instances
exist. I also wish to see the
off-site manufacturing of columns and pillars, carved wooden and stone facades,
stained glass windows and decorations, furniture ...
If you have a Badge ID and e-mail on record
for attending the International Microwave Symposium, the entire set of
IMS 2019 Conference Proceedings and Workshop Notes can be downloaded
ahead of time. Eligibility for access to specific files depends on your show admission
privileges. Amongst the files are: IMS Electronic Conference Proceedings, RFIC Electronic
Conference Proceedings, ARFTG Electronic Conference Proceedings, Sunday Workshop
Proceedings, Monday Workshop Proceedings, Friday Workshop Proceedings, RF Boot Camp,
Industry Workshops, and MicroApps.
"So if I can work out a really efficient
way of changing part of this wasted noise into electrical energy, it can be charging
batteries and taking some of the load off the plane's generating plant." That passage,
from the April 1960
Carl and Jerry adventure story, reads like a modern day energy harvesting project.
Each month Popular Electronics included an electronics saga that normally
included some high tech sleuthing by the teenagers a la the Hardy Boys. This is
a particular favorite of mine because it involves a radio controlled airplane model.
BTW, according to the Google translator, the title of this story is "The Electronic
Z-Communications, Inc., the world leader in
the manufacture of VCOs (Voltage Controlled Oscillators) and PLLs (Phase-Lock Loops),
today announced that its manufacturing facility located in San Diego, California
as of April 2019 has successfully achieved the Aerospace Management System
AAS9100D with ISO 9001:2015 Certification. "AS9100D certification signifies
that we as a supplier have established, maintained, and continually improve our
comprehensive quality management system to ensure supply of safe and reliable products
to the aviation, space, and defense industries as well as complying with civilian
and military requirements. I am extremely proud of the entire Z-Communications team.
It is a testament to the dedication ...
Some things just don't look right. This is
one of them. "Experts at BAE Systems will demonstrate a new
dual-band towed decoy to help U.S. Navy F/A-18E/F
jet fighter-bomber pilots avoid modern sophisticated enemy radar-guided anti-aircraft
missiles. The DBD towed decoy project, launched last June, seeks to meet an urgent
Navy need to protect crews of area-penetrating attack jets like the F/A-18E/F from
enemy radar-guided missiles that operate on two separate frequencies, such as X-band
and S-band. Dual-band radar is particularly difficult to jam, and poses a serious
threat to U.S. aircraft that must operate in contested airspace. A towed decoy trails
behind the aircraft ..."
ERZIA serves critical aerospace and defense
missions by designing and manufacturing RF, microwave,
and mm-wave amplifiers, integrated assemblies operating from low frequencies
up to 100 GHz, and by providing high reliable satellite communications. The
company was founded in 2002 to become a worldwide reference of advanced engineering,
performance, reliability and ruggedness. Their catalogue of standard amplifier modules
comprises more than 100 different models, having also a high capacity of customization
for amplifiers and integrated assemblies. Some of products have space heritage and
are used in aerospace, commercial, military and scientific systems, having a wide
range of final applications ...
As the planet's population grows older and
people have an increasing amount of disposable income and spare time, the opportunity
to engage in nostalgic endeavors has gone up. That includes
collecting, restoring, and operating equipment and peripherals that were the
mainstay of their lives during their halcyon days of youth. In recognition of the
new marketing opportunities, industries are popping up to feed the frenzy. Look
no farther than eBay and the amount of vintage items available for purchase - at
ever increasing prices. Having myself been an eBay buyer of memorabilia from my
early model airplane, model rockets, and electronics hobbies, I have watched prices
soar in many cases. Turntables (aka phonographs, or for the lowbrow types, record
players) are being manufactured again ...
Keysight Technologies is offering a nifty
Network Analysis Measurement Science Poster. For the price of
providing them with your e-mail address, you can either download the poster in a
PDF file format, or have a hard copy mailed to you (I suggest the latter option).
This kind of posters are reminiscent of the pre-smartphone days when office and
lab walls were lined with cool and useful posters. "This poster guides you through
the essentials and equip you with the right knowledge on network analysis measurement
science, from S-parameters basics, to common measurement applications and tips to
perform complex measurements with your vector network analyzer ..."
A recurring theme is appearing in articles
regarding the promises made for ubiquitous and omnipresent 5G and its high bandwidth
data: Atmospheric absorption is severe at the higher carrier frequencies, which
limits range and requires denser base station populations. This Pasternack article
in Microwave Product Digest entitled, "The Reality of Millimeter Wavelength for 5G"
touches on the issue. "Amid the attention to the coming fifth generation of 'cellular'
technology, the use of spectrum at 28 GHz and higher is generating some of the attention.
Most media coverage recites the well-known challenges associated operating at millimeter
wavelengths and how it will require a huge number of small-cell case stations, massive
In July, it will have been twenty years since
RFCafe.com made its debut on the World Wide Web (that's what the Internet was still
referred to by many people in 1999). At the time, the electronics world was long
vacuum tube era, but there was still enough of the vintage equipment around
that a lot of hobbyists had an interest in the theory and operation of tubes. Two
decades later you might think interest levels would have waned, but thanks to the
Internet, there are probably more people than ever who are preserving, restoring,
and using vacuum tube gear. New books are being written about them. For the layman
wanting to be educated on the art of tubes, the military's electronics training
courses are still some of the finest sources available - and they're in the Public
Domain (aka "Free") now ...
"Fiber optic gyroscopes, which measure the
rotation and orientation of airplanes and other moving objects, are inherently limited
in their precision when using ordinary classical light. In a new study, physicists
have experimentally demonstrated for the first time that using
entangled photons overcomes this classical limit,
called the shot-noise limit, and achieves a level of precision that would not be
possible with classical light. The physicists, led by Matthias Fink and Rupert Ursin
at the Austrian Academy of Sciences and the Vienna Center for Quantum Science and
Technology, have published a paper on the entanglement-enhanced fiber-optic gyroscope ..."
Triad RF Systems designs and manufactures
RF power amplifiers
and systems. Triad RF Systems comprises three partners
(hence 'Triad') with over 40 years of accumulated
knowledge of what is required to design, manufacture, market, sell and service RF/Microwave
amplifiers and amplifier systems. PA, LNA, bi-directional, and frequency translating
amplifiers are available, in formats including tower mount, benchtop, rack mount,
and chassis mount. "We view Triad more as a technology partner than a vendor for
our line-of-sight communications product line." Please check to see how they can
help your project ...
We really have it good today compared to the
early days of the semiconductor revolution. Most of the most difficult problems
were solved long ago. Point contact devices were still fairly commonplace even in
1964. Recall that the very first manufactured solid state diodes and transistors
were the point contact type that were
encapsulated in glass with a space gap where the contact was made. That left
the device vulnerable to vibration and impact damage and to contamination if the
hermetic seal failed between the metal lead and the junction(s). Unitrode claims
to have been the first to eliminate that issue with essentially a fully bonded package.
Keep in mind, however, that even the early semiconductor device packaging was no
worse that the vacuum tubes that they replaced, since the tubes also suffered from
the same vulnerabilities due to their construction. In fact, the process used with
the early solid state device packaging descended directly from vacuum tube construction ...
Most visitors to RF Cafe are either engineers,
technicians, or hobbyists who deal with watts in terms of
electrical power. This article from the January 1957 edition of Popular
Electronics deals primarily with watts in terms of acoustic power, but it also
addresses how obtaining acoustic watts relates to electrical watts. Audiophiles
will appreciate the table of speaker watts needed based on your room volume as well
as rules of thumb for selecting the amplifier power required to deliver that sound
effectively. You will note that back in the day the common abbreviation for decibels
was all lower case (db) ad opposed to how we do it today (dB). A tech-related comic
was on a page in the article so I included it as well ...
"Semiconductors, which are the basic building
blocks of transistors, microprocessors, lasers, and LEDs, have driven advances in
computing, memory, communications, and lighting technologies since the mid-20th
century. Recently discovered two-dimensional materials, which feature many superlative
properties, have the potential to advance these technologies, but creating
2D devices with both good electrical contacts
and stable performance has proved challenging. Researchers at Columbia Engineering
report that they have demonstrated a nearly ideal transistor made from a two-dimensional
(2D) material stack with only a two-atom-thick semiconducting layer ...
Providing full solution service is our motto,
not just selling goods. RF & Connector Technology has persistently pursued a
management policy stressing quality assurance system and technological advancement.
From your very first contact, you will be supported by competent RF specialists;
all of them have several years of field experience in this industry allowing them
to suggest a fundamental solution and troubleshooting approach. Coaxial RF connectors,
cable assemblies, antennas, terminations, attenuators, couplers, dividers, and more.
Practically, we put priority on process inspection at each step of workflow as well
as during final inspection in order to actualize "Zero Defects ..."
This letter submitted to Electronics
magazine by reader Fred Standish really should have been saved for the next
April issue. He writes concerning an attempt to mathematically describe the
three-port circular-to-rectangular waveguide transition for the pictured configuration.
If I remember correctly, the first time I saw that optical illusion was sometime
in the early 1970s. The drawing showed Alfred E. Neuman (the red-haired, freckled-faced
"Me Worry? guy from Mad magazine) attempting to don a pair of pants (a
triplet of pants in that case?) sewn to resemble the three-legged configuration
- known unofficially as the "Impossible Trident." I was in my early teens at the
time and though it was awfully clever. After doing a little research, I found that
the first instance of the Impossible Trident in Mad magazine was on the
cover of the March 1965 issue ...
Landing System Made to Enter Spoofing
what the airplane passenger who is always skittish does not want to hear: Radio
navigation on planes for landing purposes is not secure; signals can be hacked.
In a video demonstration of the attack by researchers, 'Wireless Attacks on Aircraft Landing Systems,,'
spoofing starts automatically as soon the aircraft enters 'the spoofing zone. The
attacker signal is in real-time generated accounting for the maneuvers of the aircraft.'
What does the spoof actually do, to trick the pilot? Dan Goodin in Ars Technica
said the researchers can spoof airport signals in a way that causes a pilot's navigation
instruments to falsely indicate ..."
Acrylic wall-to-wall carpeting really came
into vogue in the late 1960s to early 1970s - just in time for the arrival of miniaturized
microelectronics (is that redundant or just superfluous?). Gate widths were being
shrunken rapidly as the birth of the Moore's Law era was in its infancy (born in
a 1965 paper written by Intel engineer and co-founder Gordon Moore). The result
was copious quantities of
electronic gadgets being zapped when the unsuspecting user would walk across
the Van de Graaff generator in the form of floor covering and reach for a dial or
switch. A couple thousand volts could easily build up on a body clad in lime green
polyester pants (remember the era), then fzzzzt, there goes the clock radio or AM/FM
tuner. Vacuum tube circuits from a decade earlier ...
On May 27, 1868, the first
Memorial Day, originally known
as Decoration Day, was celebrated to honor the country's fallen during the Civil
War. By proclamation of General John A. Logan, "The 30th of May, 1868, is designated
for the purpose of strewing with flowers, or otherwise decorating the graves of
comrades who died in defense of their country during the late rebellion, and whose
bodies now lie in almost every city, village, and hamlet churchyard in the land.
In this observance no form of ceremony is prescribed, but posts and comrades will
in their own way arrange such fitting services and testimonials of respect as circumstances
may permit." Today, Memorial Day is celebrated at Arlington National Cemetery ..."
Rohde & Schwarz develops, produces and
test & measurement, information and communications technology.
Focus is on test and measurement, broadcast and media, cybersecurity, secure communications,
monitoring and network testing. Markets serviced are wireless, the automotive industry,
aerospace and defense, industrial electronics, research and education, broadcast
and media network operations, consumer electronics, cybersecurity for business and
governments, communications and security solutions for critical infrastructures
and the armed forces, reconnaissance equipment for homeland and external security,
and much more ...
Here is a specially constructed crossword
puzzle in honor of our fallen service members for this
Memorial Day. Since 2000, I have been creating custom engineering- and science-themed
crossword puzzles for the brain-exercising benefit and pleasure of RF Cafe visitors
who are fellow cruciverbalists. The jury is out on whether or not this type of mental
challenge helps keep your gray matter from atrophying in old age, but it certainly
helps maintain your vocabulary and cognitive skills at all ages. A database of thousands
of words has been built up over the years and contains only clues and terms associated
with engineering, science, physical, astronomy, mathematics, chemistry, etc. You
will never find a word ...