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5 of the April 2019 homepage
archives.
Friday 6
Wind down the week with these four
electronics-themed comics from a 1970 issue of Radio-Electronics
magazine. As mentioned before, radio and television technology was a big deal in
the era. People hadn't been born into a world of transistorized microcircuit media
devices that perform nearly every conceivable function - phone, TV, radio, computer,
heart rate monitor, voice recorder, remote control, camera, compass, game, social
media, etc., etc., etc. Unlike today's electronics products that typically don't
break with normal use and do not require periodic alignment, folks from my demographic
were used to turning on a TV or radio and having to readjust it or have it repaired...
"A new billboard on Interstate 40 in Tennessee
promotes ARRL and
Amateur Radio. Working with ARRL Product Development Manager Bob
Inderbitzen, NQ1R, and Communications Manager Dave Isgur, N1RSN, ARRL Graphic Designer
Sue Fagan, KB1OKW, completed a design for a the new 10 × 20 billboard, owned by
ARRL Life Member Cliff Segar, KD4GT. Segar says the average daily traffic count
for the area along I-40 west bound, mile marker 336, is on the order of 6 million
vehicles per year..."
INSTOCK Wireless Components designs &
manufactures UHF/RF power dividers, bias tees, GPS antenna signal splitters, DC
blocking L-Band splitters, high-power combiners, and current steering splitters
with models in 2-way thru 64-way configurations with Type N, SMA, TNC, BNC, &
QMA connectors covering frequencies from 10 MHz to 6 GHz. Custom configurations
also available including mix-and-match connector options, IP67 outdoor weatherproof,
rackmount, and micro-sized units...
Open & closing dates April 19 to May
3, 2019. Pay scale & grade GS 12 - 13. Salary $83,398 to $128,920 per year.
"The FCC has announced a position opening that may be of interest to a radio amateur.
The Commission seeking a
Telecommunications Specialist to work at the High Frequency Direction
Finding Center (HFDFC) in Columbia, Maryland. This is a full-time position. The
person holding this position performs 'watch duty' and serves as a technical authority
providing technical assistance and guidance to communication systems users to resolve
radio interference complaints and problems. The telecommunications specialist uses
radio signal analysis equipment deployed throughout the US to collect, correlate,
and analyze ...
Some 70 stations have registered to take part
in the 2019
International Marconi Day (IMD) observance on Saturday, April
27. Registered stations will operate at sites with a personal connection to wireless
pioneer Guglielmo Marconi, including sites at which he set up transmitting and receiving
stations. The 24-hour Amateur Radio event celebrates the birth of Marconi on April
25, 1874, and is typically held on the Saturday closest to Marconi's birthday. During
IMD 2019, radio amateurs around the world will make contact with historic Marconi
sites. The event is sponsored by the Cornish Radio Amateur Club, which will operate
as GB4IMD. While April 27 is the day of the official celebration, some IMD special
events will take place outside ...
Axiom Test Equipment
allows you to rent or
buy test
equipment, repair
test equipment, or sell
or trade test equipment. They are committed to providing superior customer service
and high quality electronic test equipment. Axiom offers customers several practical,
efficient, and cost effective solutions for their projects' TE needs and is committed
to providing superior customer service and high quality electronic test equipment.
Please check out Axiom Test Equipment today!...
Thursday 25
Reading this article about the
G-line antenna lead-in in a 1955 issue of Radio & Television
News magazine, I wonder whether the Broadband over Power Line (BPL) system
designers have considered its use. According to author Leonard Lieberman, the presence
of insulation over the conductor prevents or at least significantly reduces the
amount of radiated energy, thus lessening not just the signal loss but also the
unintentional interference with unrelated receiving equipment - such as the well-publicized
impact on amateur radio. The David Bogen Company, of New York City, (now in New
Jersey) marketed G-Line under under license by Surface Conduction, Inc. Current
BPL systems are typically under 100 MHz, so the scheme should be applicable.
The logistics of implementation...
Robert Gary waxes philosophical on the subject
of ground in his Electronics World article, "'Grounds' for Confusion." He is justified from the viewpoint of
someone attempting to make sense of how something as seemingly fundamental as Earth
ground is not a constant. The layman probably doesn't care. Practitioners in the
electrical and electronics realms who deal only with low frequencies and short distances
might occasionally be affected by differences in ground potentials, although they
might not realize it is the cause of their problems. Those with more than a casual
involvement (designers, installers, and maintainers as opposed to only users) in
high frequencies and/or long distance signal interconnections are likely to be intimately
familiar with the effects of ground potential differences. RF Cafe visitors are
undoubtedly members of the latter group...
The Electronic Design Innovation Conference and
Exhibition (EDI CON) announced that this year, in conjunction with Microwave
Journal (MWJ) and Signal Integrity Journal (SIJ), it will host an online, interactive
event for high frequency and high speed design engineers on September 10-12, 2019.
The interactive technical sessions will occur at no cost to attendees, and sponsors
will have the opportunity to present workshops and keynote sessions as part of the
daily schedule. The sessions on September 10th will focus on 5G and IoT, September
11th on radar and antennas, and September 12th on signal integrity, power integrity,
and EMC/EMI. Attendees select the sessions for the online event...
Inasmuch as new people are entering the realm
of electronics all the time and are voraciously hunting for and consuming as much
basic knowledge as possible, I figure this
primer on decibels will be a good reference. It helps clear up
one of the biggest stumbling blocks for decibels: when to use 10*log(out/in) vs.
20*log(out/in). Bob Witte has written quite a few nice articles about various aspects
of electronics. "Decibels are commonly used in electronic systems that include RF,
audio, and more recently, signal integrity. While many engineers already think in
decibels, if you mostly work in the time domain, you may not think the same way.
Because much of my background is in RF, I tend to associate the decibel with RF
measurements, but the decibel began at audio frequencies defined by telephone system ..."
"Scientists at the Department of Energy's
SLAC National Accelerator Laboratory, have developed a new type of
pocket-sized antenna that could enable mobile communication in
situations where conventional radios don't work, such as underwater, through the
ground and over very long distances through the air. The device emits very low frequency
(VLF) radiation with wavelengths of tens to hundreds of miles. These waves travel
long distances beyond the horizon and can penetrate environments that would block
radio waves with shorter wavelengths. While today's most powerful VLF technology
requires gigantic emitters, this antenna is only four inches tall, so it could potentially ..."
Centric RF is a company offering from stock
various RF and Microwave coaxial
components, including attenuators, adapters, cable assemblies, terminations,
power dividers, and more. We believe in offering high performance parts from stock
at a reasonable cost. Frequency ranges of 0-110 GHz at power levels from 0.5-500
watts are available off the shelf. Order today, ship today! Centric RF is currently
looking for vendors to partner with them. Please visit Centric RF today...
Wednesday 24
Operators didn't know how good they had it
in 1967. The story talks about the nuisance of having to sift through "hundreds"
of satellites, old rockets, and assorted space junk" in order to search for and
track potentially threatening objects in orbit around the Earth. We're into the
millions of objects in 2019, and the potential threats are infinitely larger. The
article mentions the use of an
AN/FPS-16 radar operating in C-band to detect and measure the
returns and then the results were analyzed in an attempt to determine the character
of the object. Open air test sites and anechoic chambers were used to measure the
radar cross section and characteristic signature of many shapes to populate a database
of recognizable returns that would help to determine whether the space object was
friend or foe...
The NI AWR Design Environment platform will
be featured in an upcoming free webinar on Wednesday, May 15. Presented is a new
technology and design methodology that uses the
impedance-matching network synthesis capabilities within Microwave
Office circuit design software to design the input impedance for a new generation
of Virtual Antenna™ tiny antenna booster components from Fractus Antennas. This
antenna technology enables a single antenna component to fit seamlessly in a printed
circuit board (PCB), replacing conventional customized antennas for internet of
things (IoT) and other wireless applications...
"A new, first-of-its-kind
space weather model reliably predicts space storms of high-energy
particles that are harmful to many satellites and spacecraft orbiting in the Earth's
outer radiation belt. A paper recently published in the journal Space Weather details
how the model can accurately give a one-day warning prior to a space storm of ultra-high-speed
electrons, often referred to as 'killer' electrons because of the damage they can
do to spacecraft such as navigation, communications, and weather monitoring satellites.
This is the first time researchers have successfully predicted those killer electrons
across the whole outer belt region ..."
Studies of motors usually begin with the
direct current (DC) type - maybe because most students have already
had hands-on experiences with motors in models (cars, boats, airplanes) and/or electricity
experimenter kits. They are small, cheap, and a simple flashlight battery (the ultimate
in safety) makes them run. An alternating current (AC) motor requires either a direct
connection to the house current or use of a step-down transformer, which still carries
with it a high risk factor. This chapter of the U.S. military's Basic Navy Training
Course (NAVPERS 10622) conforms to the tradition, and follows in the next chapter
with AC motors and generators. While reading through the text, I ran across the
unfamiliar term "kickpipe" and wondered...
Since 1961, MECA
Electronics has designed and manufactured an extensive line of
RF & microwave
components for in-building, satellite, radar, radio, telemetry, mobile radio,
aviation & ATC. Attenuators, directional & hybrid couplers, isolators &
circulators, power dividers & combiners, loads, DC blocks, bias-Ts and adapters &
cables. MECA has long been the 'backbone' of high performance wired and air-interfaced
networks such as in-building applications, satellite communications, radar, radio
communications, telemetry applications, mobile radio, aviation & air traffic
communications...
Tuesday 23
Air Route Traffic Control Centers, now using
the acronym ARTCC rather than ARTC as used in this 1960 article, were and still
are the human and computer command and control facilities responsible for safe and
orderly flow of air traffic in the U.S., and a worldwide network of Area Control
Center (ACC) handles everything else in a massive coordinated effort. The advent
of radar during World War II and the ensuing evolution of it and electronic
computers in the following years struggled to keep pace with the equally rapidly
evolving aircraft design and capability. A simple control tower with air traffic
controllers using binoculars and a radio mike could not handle the volume of airplanes
and helicopters traversing the skies and patronizing busy terminals. Many forms
of electronic navigation aids were developed including very high frequency omnidirectional
range (VOR), direction finders (DF) using antenna nulling for finding radials to/from
FM radio transmitter, long range navigation (LORAN)...
VidaRF, a manufacturer of high performance
RF and microwave high performance circulators, isolators, couplers, power dividers,
and other passive components, is proud to introduce a series of broadband
Power Dividers covering 698 MHz through 2.70 GHz for
all wireless applications from cellular through UMTS. Available in 2, 3, 4, 6 and
8-way with SMA, N, QMA or alternative connector configurations. VidaRF is focused
on being a solution provider by building to customer specs and offering zero days
lead time for custom parts through stock and ship program...
Nova
Microwave is a leader in technically differentiated electronic and radio frequency
Ferrite Circulators and Isolators
that connect, protect and control critical commercial and military wireless telecommunications
systems. Our staff is dedicated to research and development of standard and custom
design quality Ferrite Circulators and Isolators from 380 MHz to 26.5 GHz.
Please visit Nova Microwave today...
Chapter 16 of the "Electricity - Basic Navy
Training Courses" introduces concepts of
alternating current (AC) motors, their electric supply, and controls.
It is part of the NAVPERS (Navy Personnel) 10622 series which is highly regarded
both in and out of the military. The manuals were first written in the middle of
the last century and have been upgraded a few times since then, but if you compare
the sections this one on AC motors in both the original and most modern versions,
not much - if anything - has changed. If you have an interest in motors and want
to understand the basics of how they work both as motors and generators (AC and
DC), then there is not a much better source from which to start ...
Jeffrey Kahler's "Complete Filter Design with Discrete Elements Made Easy" article
on the MW&RF website reviews some of the filter design software tools
currently available both as free apps from component vendors and as a subset of
big-name simulator suites. Says Jeffrey, "In an era of a myriad of design tools
developed to “save” the filter designer time and effort, it's exactly time and effort
that may be lost due to learning curves, cumbersome workflows, and limitations of
the design process itself. Powerful design tools may thus be rendered effectively
useless by any one of these problems. For example, a tool that provides powerful
synthesis may fall short ..."
"By drilling holes into a thin 2-D sheet
of hexagonal boron nitride with a gallium-focused ion beam, University
of Oregon scientists have created artificial atoms that generate single photons.
The artificial atoms - which work in air and at room temperature - may be a big
step in efforts to develop all-optical quantum computing, said UO physicist Benjamín
J. Alemán, principal investigator of a study published in the journal Nano Letters.
'Our work provides a source of single photons that could act as carriers of quantum
information or as qubits. We've patterned these sources, creating as many as we
want, where we want ..."
ConductRF is continually innovating and developing
new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF
Test Cables for labs. ConductRF makes production and test coax cable assemblies
for amplitude and phased matched VNA applications as well as standard & precision
RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the
iBwave component library. They also provide custom coax solutions for applications
where some standard just won't do. A partnership with Newark assures fast, reliable
access. Please visit ConductRF today to see how they can help your project!...
Monday 22
An excellent short history on "The Discovery of Radio Waves" was published by George Steber in
the Jan/Feb 2019 issue of Nuts & Volts magazine. "When the concept
of electromagnetic waves was first proposed around 1864, it was met with great skepticism.
As a result, the idea languished for a long time. This is understandable since the
foundations of the theory were complex and the conceptual ideas were at odds with
physical thinking. It took several decades for a handful of dedicated persons -
infatuated with the mysteries of electricity and magnetism - to finally put the
theory on a solid footing..."
Improving Object Detection with
Low-Bandwidth Radar
"Researchers at Tel Aviv University have designed
a new type of radar ranging system that requires virtually no bandwidth to operate
successfully. This new method does not have the bandwidth limitations of traditional
methods, meaning it can be used in a vast array of different applications - particularly
when it comes to the automotive industry Traditionally,
radar resolution was believed to be proportional the bandwidth
use. Essentially, the wider available range of frequencies, the better the radar
will be at detecting objects in its path. The new method devised by researchers
seeks to change all that ..."
EE Times has an interesting piece
on their website regarding how modern engineering methods might be used to restore
the fire-ravaged
Notre-Dame church to its original condition. Some interesting
observations are made, one regarding how cleaning and replacing stained glass tiles
will affect lighting to the 13th century conditions vs. as it was two weeks ago.
Another suggests ultrasonic analysis of mortar joints to structural integrity, use
of drone photos and laser measurement to construct a detailed 3D model of the building
for work planning. It also suggests a call to social media for obtain as many of
the millions of photographs taken by visitors from all perspectives and times of
day for recreating damaged or destroyed components.
If you happen to be Estonian, you might think
of something entirely different than most of us do when we hear the word "getter." In fact, you probably capitalize the word since it is
the name of a pop singer from your country, Getter Jaani. If you are a child living
in Japan, you would probably think of Getter Robo, an anime from a popular cartoon
series. I, and I dare say just about everyone else that visits RF Cafe, knows getter
as that silvery deposit (typically barium) that resides inside vacuum tubes for
the purpose of helping to maintain the vacuum and to absorb pesky random molecules
that might otherwise cause electrical noise in the circuit. This article from a
1958 edition of Radio-Electronics discusses the purpose of getter. BTW,
I had never heard of either of the other two Getters due to OGS (old guy syndrome)...
Rohde & Schwarz has published a white
paper entitled, "The Future of EMC Test Laboratories," which addresses the increasingly
difficult to meet EMI and EMC certification requirements in today's extremely crowded
electromagnetic spectrum. "The growing complexity of electronic devices within both
military and commercial products has lead to a significant increase in failure rate
of EMC conformance testing. Product design cycle times continue to decrease due
to competitive pressure in the market. Product design companies are spending more
money on multiple iterations of product EMI compliance testing at EMC test laboratories,
and this comes at a significant financial ..."
Res-Net
Microwave has a complete line of precision
RF &
microwave components including attenuators, terminations, resistors, and diode
detectors for commercial, military, and space applications. Products range from
the small flange type to large 2,000 watt connectorized power attenuators and/or
terminations at frequencies up to 26.5 GHz. In-house photo etch and laser trim
capability. Please check out Res-Net Microwave's website to see how they can help
with your current project...
Sunday 21
Since 2000, I have been creating custom
technology-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 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
surprise you...
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. I also
have an extensive list of
Recently Added topics.
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