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5 of the October 2019 homepage archives.
Friday 6
Fellow amateur radio enthusiast Russ Keller
(KM4RHK), of Wake Forest, North Carolina, has designed and is selling his
DMMCheck Plus
test device for verifying the accuracy of digital multimeters, oscilloscopes, or
other instruments which measure the provided parameters. This compact (2.5" x 2.2"),
inexpensive board is battery powered and can be used to verify the accuracy of seven
primary DMM functions. A very complete description of each function is provided
on the DMMCheck Plus website. A certificate of measured values for each function
is provided with the DMMCheck Plus. Re-measurement, if desired, is free for
the first two years ...
Once a major manufacturer of both primary
(one-time use) and secondary (rechargeable) batteries, the National Carbon Company
changed names many times through acquisitions and mergers until its current incarnation
as GrafTech International. National Carbon Co. appeared frequently in electronics
magazines during the World War II era for their innovations in portable power
supplies. They are credited for developing the world's first "D" size dry cell battery.
This advertisement in a 1958 issue of Popular Electronics heralded the company's
introduction of what was essentially what we call a
hydrogen fuel cell ...
Here is a unique new product being offered
by Rohde & Schwarz:
AdVISE Visual Inspection Software. "R&S®AdVISE
visual inspection software automates the process of visually monitoring an equipment
under test (EUT) during a test sequence. This eliminates human inattention, ensures
reproducible results and simplifies the test documentation. A typical application
is EMS testing with R&S®EMC32 and R&S®ELEKTRA test software. Automatic error
recognition on EUTs based on camera signals Continuous monitoring of all observed
regions at 30 frames per second Saves time and eliminates human inattention Generation
of test reports and event-controlled video protocols Runs independently and under
the control of system software ..."
In this article from a vintage issue of
QST magazine, the author describes the automatic
antenna
switching system which was developed for controlling the forty-odd receiving
antennas at the FCC's Grand Island Monitoring Station (Nebraska). With this system
it required only a matter of seconds for the operator to select any desired antenna
by simply pushing a couple of buttons on the control panel. A similar system could
easily be designed for a lesser number of antennas either for a test range or an
amateur radio operation. Of course modern-day antenna switching equipment does the
job handily and at a good price ...
RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave component supplier. RF coaxial connectors & adapters,
coaxial cable & cable assemblies, surge protectors, attenuators. Items added
daily. Free shipping on orders over $99. We're leading the way again!
Rohde & Schwarz has a new app note entitled,
"Understanding Preselection in EMI Receivers." "EMI (electromagnetic
interference) testing differs from traditional spectrum analysis in numerous ways,
but the most important differentiator between them lies in the nature of the signals
that are being measured. In traditional spectrum analysis, we are normally measuring
signals that we (or rather our device under test) are generating. In other words,
we are measuring known signals. In most cases we have control over both the signal's
content or modulation, as well RF-level parameters such as frequency, level, crest
factor, etc. We can easily configure or adjust our device under test ..."
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.
Thursday 5
In many ways a
crossnumber (aka cross number or cross figure) puzzle, which is an intersecting
grid of numbers, is more challenging than a standard crossword puzzle, which is
an intersecting grid of letters. John Comstock created a few of these crossnumber
puzzles for Popular Electronics back in the early days of the magazine. If you have
never tried creating a crossword puzzle, especially one that uses only technical
terms and has many interconnected squares in the grid, then you cannot appreciate
the frustration it can be. The nice thing about creating a crossnumber puzzle versus
a crossword puzzle is that every number is a valid "word" and it is therefore never
a problem to find a clue to go with it. For example, any random number can be the
answer to a clue that expresses ...
An RF Cafe visitor recently wrote to tell
about having discovered a conductive paint for creating an inexpensive shielded
room for doing RF testing. My first thought when looking up the Woremor RF-IE50
EMR & RF Shielding Paint (-44 dB
@ 4 GHz) was that it was probably a favorite of the tinfoil hat crowd that
believes the government is bombarding them with radiation and/or listening in on
their conversations. The company does recommend it for painting room walls where
smart meters are mounted on the other side, thus exploiting the paranoia. Connection
to an Earth ground is required for safety
reasons. Woremor also sells shielding
wallpaper (-82 dB @ 10 GHz),
window film (-32 dB @ 1 GHz), and other
such products. They even sell a fashionable
tinfoil hat.
"Hello Americans, This is
Paul Harvey..."
Radio legend Paul Harvey produced and performed a daily show that featured news,
commercials, and commentary. For nearly 75 years, dedicated listeners looked forward
to his show on the local AM radio stations - especially The Rest of the Story.
Scores of wars, natural disasters, crises, deaths, scientific advances, miracles,
and acts of human kindness were commented upon in Mr. Harvey's unique delivery style.
On March 19, 2003, Mr. Harvey did a pitch for the role of Amateur Radio operators
in emergency response roles. The mention was the second item on "page four" of his
Paul Harvey Noon News and Comment program. "America's quiet warriors are
the legion of ham radio operators, 700,000 of them, who are always at ready for
backup duty ..."
Copper Mountain Technologies is announcing
the release of the new
SC Series Compact VNAs for 2-port 2-path measurements. The SC Series network
analyzers feature a 140 dB dynamic range, 15 dBm output power, and a typical
measurement speed of 16 µs per point. The SC Series is the latest addition
to CMT's Compact line of VNAs and includes the SC5065 and SC5090. Both instruments
have a starting frequency of 300 kHz, the SC5065 goes up to 6.5 GHz and
the SC5090 goes to 9 GHz. All CMT VNAs include excellent customer service,
automation support, and years of engineering expertise at your disposal ...
"The electric shock you get from shuffling
along a carpet might be the first experiment in
electrostatics and tribology in most people's
lives, but what causes it remains an open question. 'A lot of people had worked
on what was taking place, for instance that electrons or ions were getting transferred
from one material to another,' says Laurence Marks, a professor at Northwestern
University in the U.S. 'However, why this should occur in the first place was not
understood.' Despite this gap in understanding, the triboelectric effect plays a
key role in a variety of fields. One perk is that the electricity generated could
replace batteries, which tend to be heavy and need constant recharging ..."
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.
Wednesday 4
Did you know that Sperry was assigned a trademark
on the term "klystron?"
The klystron vacuum tube type was actually invented by invented in 1937 by American
electrical engineers Russell and Sigurd Varian (I'm old enough to have had Varian
Associates catalogs). According to this full-page advertisement in a 1944 issue
of Radio News magazine, not only did Sperry develop the klystron vacuum
tube, but they also coined a term to describe any study or application of it: "klystronics."
Here is a very interesting excerpt from the Wikipedia page, "The work of physicist
W.W. Hansen was instrumental in the development of the klystron and was cited by
the Varian brothers in their 1939 paper ...
RF
Cafe's raison d'être is and always has been to provide useful, quality content for
engineers, technicians, engineering managers, students, and hobbyists. Part of that
mission is offering to post applicable job openings. HR department employees and/or managers of hiring
companies are welcome to submit opportunities for posting at no charge (of course
a gratuity will be graciously accepted). 3rd party recruiters and temp agencies
are not included so as to assure a high quality of listings. Please read through
the easy procedure to benefit from RF Cafe's high quality visitors ...
This
Electronics Curves Quiz will probably prove to be a little more of a challenge
than some of the ones previously appearing in Popular Electronics magazine.
Being a rocket scientist won't help you much here, but being a seasoned electronics
technician, hobbyist, or engineer will sure come in handy. Be careful to note the
axis unit labels - I got tripped up by that from being lazy and missed one. Surely
you won't be hindered by such an oversight.
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 succeed.
Mr. Conrad
Young, whom I have the pleasure of knowing from our days at RFMD and is now
the CTO at Linear Devices Company in San Jose, CA,
just published this excellent whitepaper entitled, "Where Does 75-Ohms Come from Anyway??" Much has
been written on the origin of 50 Ω coaxial cable (with some disagreement),
but not so much about 75 Ω. A delve into 75 Ω's history with the broadcast
TV industry provides a segue into some high level theoretical discussions and then
finally presenting various coaxial cable and connector configurations. It is a good
read with lots of source references for further investigation if you so desire.
"A new
antenna that uses saltwater and plastic instead
of metal to shape radio signals could make it easier to build networks that use
VHF and UHF signals. Being able to focus the energy of a radio signal towards a
given receiver means you can increase the range and efficiency of transmissions.
If you know the location of the receiver, and are sure that it's going to stay put,
you can simply use an antenna that is shaped to emit energy mostly in one direction
and point it. But if the receiver's location is uncertain, or if it's moving, or
if you'd like to switch to a different receiver, then things get tricky. In this
case, engineers often fall back on a technique called beam-steering or beamforming,
and doing it at at a large scale is one of the key underlying mechanisms behind
the rollout of 5G networks ..."
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.
Tuesday 3
Every time I see something about "transparent
anything" that formerly was know only in an opaque form, I think about the Star
Trek "The Voyage Home" movie (click on the link if you don't know what I mean).
This
transparent ceramic material was a real breakthrough in optics technology in
its day due to the ability to control its degree of transparency or opacity with
an electric field. It would even retain its state with the electric field removed
so use as a data or even image storage device was possible. An ability to be quickly
switched (at up to a 10 MHz rate) held promise for it as a laser or other light
source modulator or even as a high speed facsimile (fax) system. It seems sort of
like a solid version of a liquid crystal display (LCD). Lots of unique optics terms
appear in this article ...
Engineering whitepapers, pamphlets, books, magazines,
and chapter examples listed here are a small sample of a lot of new items that are
offered for FREE through TradePub. The publishers make them available to qualifying
people as a promotional campaign for their full line of offerings. Free e-books
like "Maximizing LinkedIn for Business" and "20 Questions You Should Never Ask in
an Interview" are examples. Magazine titles include Microwave Engineering Europe,
Electronic Design, and Microwave Product Digest.
"Modelithics is pleased to announce the release
of the newest version, version 19.3, of the
COMPLETE Library for use with NI AWR Design Environment software platform. This
update includes 65 new models. Designers will be thrilled with the new release of
the Modelithics COMPLETE Library for NI AWR Design Environment, specifically Microwave
Office circuit design software. The addition of 65 new models significantly increases
the library content, with the library now representing over 17,000 components. New
Microwave Global Models™ for passive components are available for Coilcraft, DLI
(Knowles), Exxelia, and Syfer (Knowles), including ten new ferrite beards, seven
capacitors and two inductors for Würth Elektronik. This release also includes three
new resistors and five attenuators ..."
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.
Here is a little insight into early
speech processing research by the Bell Telephone Laboratories. 1957 was the
early era of real-time digital processing where the need to cram more calls into
less signal space (bandwidth) led to sampled systems - 1:6 in the case of this advertisement
from Bell that appeared in Radio & Television News. Engineers of the
day would be amazed at how the state of the art has advanced since then, both in
mathematical techniques and in miniaturized hardware. Waaaaay back in the early
1990s while working at Comsat Laboratories, in Germantown, Maryland, one of the
Intelsat earth station modem transceivers I worked on used groundbreaking software
algorithms to reduce call bandwidth ...
"A
roving security robot - oblong and about four-feet-tall
- plunged into a water fountain outside a Washington, D.C., office building Monday
afternoon, sending online commentators into a tizzy and causing many people to spot
plenty of metaphors for the much-promised autonomous future. Numerous photos posted
online showed the robot on its side in the ankle-deep water as workers tried to
figure out how to rescue it. The autonomous machine was apparently making its usual
rounds outside the Washington Harbour office and retail complex in Georgetown when
it tumbled down some steps and into the fountain ..."
Transient Specialists specializes in
EMC test
equipment rentals and carries a complete line of ESD guns, surge immunity test
equipment, and EFT generators. Rentals available for military (Mil-Std 461), automotive
(ISO 7637), and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited
calibrations and technical support on EMC testing equipment offered. Equipment consists
of top EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and
EMC Partner. Contact Transient Specialists today for your ESD / EMC / RFI testing
needs.
Monday 2
This article reporting ongoing research for
auto anti-collision systems and backup warning systems appeared in a 1972 issue
of Popular Electronics has only come to practical fruition within the last
decade and a half. High-end cars were offering such equipment options in the
early 2000s, but it has only been commonplace since around 2010. 1972 components
were still pretty large and power hungry, and digital processing capacity and speed
was significantly less advanced as well. Bendix, one of the early developers of
anti-collision systems, estimated that the option on a new car might add about $200
to the price, which was a really ambitious estimate, even considering that is the
equivalent of $1,230 in 2019 money per BLS Inflation Calculator. The total add-on
cost of both anti-collision and backup warning systems ...
The 2019 IEEE International Symposium on Phased Array Systems
and Technology will be held from October 15th through 18th at the Westin Hotel
in Waltham, Massachusetts, on Boston's famous Route 128 Technology Highway. The
symposium will include keynote and plenary sessions, parallel technical sessions,
poster sessions, tutorials, and a student paper contest. Social events will include
a welcome reception with dinner and an awards banquet. This symposium will present
the most recent advances in phased array technology and provide a unique opportunity
for members of the international community to interact with colleagues in the field
of phased array systems and technology.
Anatech Electronics, Inc. offers the industry's
largest portfolio of high-performance standard and customized RF and microwave filters
and filter-related products for military, commercial, aerospace and defense, and
industrial applications up to 40 GHz. Anatech has introduced three new
directional coupler designs: a 0.5-26.5 GHz, 30 dB directional coupler
that handles up to 20 watts, a 0.5-100 MHz, 30 dB directional coupler
for up to 3 watts, and a 300-8000 MHz, 20 dB directional coupler for up
to 20 watts. Custom RF power directional coupler designs can be designed and produced
when a standard cannot be found, or the requirements are such that a custom approach
is necessary.
There is a twofer on this page - a feature
article and a couple related
electronics-themed comics. Point-to-point wiring of electronics
assemblies is rarely seen these days. For that matter, the use of leaded components
is rarely seen these days. The advent of printed circuit boards was a real breakthrough
concept when they became commercially viable in the 1950s. As the comic at the bottom
of the page suggests, many people did not even know what a printed circuit board
was. The air traffic control radar unit that I worked on in the USAF had all point-to-point
wiring in a trailer-full of chassis. Terminal strips and bus strips, bifurcated
terminals, tube socket terminals, and studs from relays and switches were the connection
points ...
"A team of researchers from NIST has successfully
created and demonstrated a new type of sensor that relies on atoms to receive communication
signals. Researchers believe that their new
atom-based receiver could potentially offer a significant advantage
over those currently on the market by providing a smaller device that works better
in noisy environments. The team used cesium atoms (1s and 0s) to receive digital
bits in the most commonly used communication format, which is best known as phase
shifting or phase modulation, and is used by satellite televisions and Wi-Fi, to
name just a few. With this particular format, electromagnetic waves such as radio
signals are shifted relative to one another over a specific period ..."
Please take a few moments to
visit the
everythingRF website to see how they can assist
you with your project. everythingRF is a product discovery platform for RF and microwave
products and services. They currently have 227,460 products from more than 1210
companies across 285 categories in their database and enable engineers to search
for them using their customized parametric search tool. Amplifiers, test equipment,
power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers,
power supplies, and everything else. Please visit everythingRF today to see how
they can help you.
Sunday 1
For two decades, 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. This September 29, 2019, puzzle uses a database of thousands
of words which I have 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 taxing your knowledge of a numbnut soap opera star
or the name of some obscure ...
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
About RF Cafe.
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