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3 of the June 2018 homepage archives.
Friday 29
Lightning season is upon us once again. The National
Weather Service says June, July, and August, are the most active lightning months in
the U.S., which is probably true in all of the northern hemisphere, and then December,
January, and February in the southern hemisphere. According to the National Safety Council,
the average American has a 1:114,195 chance of being
killed by lightning
in a lifetime (which ends abruptly upon being killed). That's much less than
your chance of dying due to cancer (1:7) or being killed in a car accident
(1:102), but is sucks if you're that one in 114,195. Not all lightning strikes
are fatal, but many cause personal and property damage. Mitigating the chance of
being harmed requires taking some simple actions to not expose...
Design News has a new batch of entries
for the "You Might Be an Engineer If..."
feature. How many describe you? The only one I don't agree with is that
engineers are not (or should not be) concerned with proper grammar because
language is too imprecise. It is one thing to end a sentence with a preposition
or unintentionally misspell a word, but mixing up contractions like "your" and
"you're," or "its" and "it's," is, IMHO, inexcusable. Engineers - and every
educated person who knows better - should strive to set a good example for
others...
Glen Robb, proprietor and chief engineer of Antenna
Test Lab, has posted a series of short white papers on his company's website. Among them
is one titled, "What Is an Anechoic Chamber?," which has, among others, the picture
shown in this thumbnail that uses a mirrored room (i.e., a house of mirrors) to illustrate
the concept of a space with infinite reflections. Identifying the true location of an
image is difficult. Paint all the surfaces flat black and you have an optical wavelength
anechoic chamber. If creating an RF nonreflective chamber was that easy, there
wouldn't be as much need for enlisting the help of testing services - presuming
you have an experienced test expert on hand. Fortunately, Glen is standing by
awaiting your call...
TGIF, and that means
tech-themed comics from vintage electronics magazines if I happen to have any. You'll
really appreciate the comic on page 96 of the 1965 issue of Popular Electronics.
In a way, the drawing's concept was very prescient regarding the future of
flexible, bendable circuits. A big part of the electronics world at the time
centered around servicing all the newfangled circuits and test equipment for
troubleshooting and aligning them. As is still true today, technology changed
quickly and there was always a newer model television, radio, tape recorder,
stereo system, video recorder, etc. Customer interactions and repair shop
experiences...
I sat stunned yesterday while listening to the
radio report of the shooting at the Capital-Gazette newspaper offices in Annapolis, Maryland.
My father, Art Blattenberger, was the classified ad
department manager there for more than two decades,
back when it was called the Evening Capital, and was located downtown on West
Street. Even though Annapolis is 300 miles away from Erie, the event still feels close
to home. My sisters still live in the area, but none work at The Capital.
"Nippon Telegraph and Telephone
Corporation and Tokyo Institute of Technology have jointly developed an ultra
high-speed IC for wireless front-ends that operates in the terahertz frequency
band. This new IC technology has achieved 100 gigabit per second (Gbps) wireless
transmission data rates in the 300 GHz band. The details of the technology were
presented at the 2018 IEEE MTT-S IMS 2018 in Philadelphia last week. Terahertz
waves are being used for a wide range of research projects as this is one
frequency where wide frequency bands..."
Thursday 28
A year has passed since I last posted a
Carl and Jerry high-tech saga. John T. Frye created the duo of teenage
sleuths in 1954 for the very first issue of Popular Electronics magazine. More than 100
adventures carried Carl and Jerry from high school through college. Their practical jokes,
crime solving, and mystery investigations incorporated microphones, timers, cameras,
Ham radio, transformers, metal detectors, remote controllers, home brew circuits, photodetectors,
and a host of other gadgets that could be pulled from a stash of parts in Carl's or Jerry's
basement workshop, or borrowed from a friend. In this story, Carl and Jerry, now students
at Parvoo University in Indiana, have an unexpected confrontation with a radio
operator while exploring a campus...
"The advent of precision guided weapon technologies
has greatly reduced the military's 'cost per kill,'
along with the associated logistics and supply costs for maintaining a large
number of conventional munitions in inventory. Key to this advance is the
integration of advanced guidance, navigation and control (GNC) systems using
laser, electro-optical, infrared, radar and/or GPS signals to direct the weapon
to its designated target. To counter this threat, adversaries are increasingly
turning to electronic attack measures to disrupt the operation of these GNC
systems. Mitigation of adversarial attack is accomplished through the
integration of self-protection capability..."
"Who needs another
color code chart?," you might be asking. Well, as is always the case there
are new people coming into the electronics field all the time and they are
looking for resources just as we were lo those many years ago when we were first
smitten by the science. For that matter, a lot of seasoned electronics
professionals and hobbyists decide to take on the task of refurbishing or
repairing vintage equipment and need a quick reference for interpreting the
colored dots and stripes on resistors, capacitors, and inductors, as well as the
colors of transformer lead wires...
Withwave's
T-Probe is coaxial probe that offers one signal pin on center and several fixed
pitch ground contact with low inductance. This probe provides excellent electrical performance
for applications having test point with adjacent grounds. They have various pitch ranges
of 0.8, 1.5, 2.5 mm from signal to ground contacts and are produced by precision
manufacturing process. The
T-probe
is available for signal probing test in these applications such as RF module
signal insertion/output measurement , high speed digital & high frequency
circuit board analysis...
"In 1965, a renowned Princeton University physicist
theorized that
ferroelectric metals could conduct electricity despite not existing
in nature. For decades, scientists thought it would be impossible to prove the theory
by Philip W. Anderson, who shared the 1977 Nobel Prize in physics. It was like trying
to blend fire and water, but a Rutgers-led international team of scientists has verified
the theory and their findings are published online in Nature Communications. 'It's exciting,'
said Jak Chakhalian, a team leader of the study and Professor Claud Lovelace..."
Wednesday 27
Nothing has change in the design and application
of
resistive attenuator pads since this article appeared in a 1959 issue of Electronics
World. It could be legitimately reproduced verbatim in the August 2018
issue of any magazine. When you crank through the equations you will arrive at
resistor values slightly different from those presented here because the author
chose the nearest standard 5% tolerance resistor values. For instance the 10 dB,
T-type attenuator for 75 Ω terminations shown in Figure 7 gives series branch
resistors of 33 Ω and a parallel branch resistor value of 51 Ω. The result is an
attenuator that does not present exactly the desired input and output impedances
or the exact attenuation value. More precise values are 39.0 Ω and 52.7 Ω...
All RF connectors are not created equal. Aside
from form factor, environmental (temperature, humidity, vibration, etc.) tolerance, power
handling, and cable type accommodation, the RF characteristics must be considered for
optimum performance. For example, you should never use a BNC connector for C-band satellite
transceiver because the frequency is too high for acceptable s-parameters. An SMA connector,
although rated through 18 GHz, would not be used at the output of a 100 kW
VHF commercial broadcast TV power amplifier even though it operates at only a couple
hundred MHz. RF & Connector Technology
(RFCT) has a handy-dandy chart to help you choose your connector based on
frequency...
A few months ago I posted a write-up on the vintage
Alliance Model U-100 Tenna-Rotor that I installed in the garage attic with a
Channel Master CM5020 VHF / UHF / FM antenna atop it. There are not many television
antenna manufacturers around anymore; their numbers have been decreasing continually
due first to the advent of cable-delivered TV and now with Internet-delivered TV. The
"cord-cutter" movement is helping to give over-the-air television broadcasting a rebirth
due to the outrageous cost of subscription programming. Anyone contemplating installing
a television antenna today has the same concerns as those back in 1959 when this Channel
Master advertisement appeared in Electronics World magazine - gain,
directivity, bandwidth, ruggedness...
"Qorvo, a leading provider of innovative RF solutions
that connect the world, high-performance,
X-band front end modules
(FEMs) designed for use in next-generation active electronically scanned array
(AESA) radar. These export-compliant gallium nitride (GaN) products also meet
the need for high RF power survivability essential for mission-critical
operations. The demand for RF front end components for radar applications is
expected to exceed $1B by 2022, growing at 9% CAGR over the next five years. The
market for RF GaN devices..."
Since 2001,
Antenna Test Lab Co has evaluated countless antennas and RF transmitter
products. With a fully anechoic
chamber, antennas can be quickly developed and RF products
refined and deployed. Mounting surfaces like drywall, glass, wood, and even curved metal
simulated automobile available. The price for a standard
resolution
2D or 3D field pattern plot is only $450
- for a passive or radiating antenna. That is an incredible deal!
"IBM threw down a challenge in March of this year
when they built what they claimed was the
world's smallest computer.
The IBM computer is smaller than a grain of rock salt, but computing engineers
around the world decided they'd attempt to go smaller. The challenge also didn't
sit well with a team at the University of Michigan who previously held the
record for world's smallest computer. After months of development, the Michigan
team announced they've bested their corporate challengers. The computing device
they created measures only 0.3 mm on a side..."
Tuesday 26
"In the
photoelectric effect, a photon ejects an electron from a material.
Researchers have now used attosecond laser pulses to measure the time evolution
of this effect in molecules. From their results they can deduce the exact
location of a photoionization event. When a photon hits a material, it can eject
an electron from it provided it has enough energy. Albert Einstein found the
theoretical explanation of this phenomenon, which is known as the photoelectric
effect, in Bern during his 'year of wonders' 1905. That explanation was a
crucial contribution to the development of quantum mechanics, which was under
way at the time, and it earned him the Nobel Prize in Physics in 1921..."
Electronics-themed comics are usually saved for
Fridays, but what the hey; maybe you need some humor on Tuesday this week. At least three
of these
antenna-based comics required a harder look to determine what was happening
and why it is humorous. One of those even requires a little technical insight to
"get it." To see my take on the comics, highlight the text...
Practical
Wireless is Great Britain's largest selling amateur radio magazine. As with
the ARRL's QST magazine, it has monthly reviews on the latest radio and test
equipment, exclusive features, club event listings, building projects, and more. You
can get a hard copy in the mail if you're willing to pay a lit extra for shipping
charges.
Bundle in a
Radio User subscription and you will also receive features on
all forms of radio listening - broadcast, airband, scanning, DXTV, weather satellites,
amateur bands, decode, SSB utilities, numbers stations, milair and propagation. ...
All of the
oscilloscope measurement techniques presented in this 1960 Electronics World
article apply to 2018 circuit measurements. Anyone who attended a high school or
college electronics lab has created and measured capacitance, inductance and
resonance using an o-scope as part of a classroom exercise. We all were wowed
the first time we hooked up signal generators to both the horizontal and
vertical deflection inputs and observed rotating Lissajous patterns on the
display. Don't tell me you didn't twist the frequency and amplitude knobs of the
sig gens with the delight of a kid playing with an Etch-A-Sketch. When I was
taking labs in the 1970's and 1980's, school oscilloscopes were all analog...
RF Cafe visitor Tom M. sent a note to let
you know about the SDRPlay spectrum analyzer software available for free downloading. Versions
are available for Windows, Mac, Linux, Raspberry Pi,
Android, and ARM64 platforms. Powerful radio configuration and post-processing
algorithms like this was available only in high-end commercial test equipment
and military gear just two decades ago. Trench-coat-clad sleuths hid in shadows
and maneuvered furtively in attempts to abscond with such magnificent
technology. Today, even more capable products are available to anyone for a
couple hundred dollars. It's a wonderful world...
"In the 1950s, NASA engineers were looking for
a quiet place to build a network of
large radio antennas.
The idea was to build a series of antennas with huge parabolic dishes and
receivers that could detect extremely faint radio signals. After scouting
multiple locations, they selected a remote stretch of the Mojave Desert near the
ghost town of Goldstone and the U.S. Army's Fort Irwin - an area. This was a
great choice as the region had no interference from power lines or commercial
radio and television transmitters. The first antenna built at the Goldstone Deep
Space Communications Complex was the aptly named Pioneer Station. The 85-foot
antenna..."
Monday 25
While not quite the equivalent of an Elvis sighting,
I was utterly surprised to see an open
Radio Shack store in the Ashtabula Towne Square Mall during a recent trip to
Ohio. As you can see in the photo, it is a shell of a store, with products on
display only along the walls. Do you remember the days when every shopping mall
and plaza had a Radio Shack crammed full of stereos, radios, calculators,
antennas, computer accessories (and the TRS-80), toys, and of course a huge
portion of the store dedicated to electronic project components? I had a
"Battery Club" card for a couple decades, and a current catalog was always on my
bookshelf. If, as the old saying goes, "Misery loves company," then the good
folks at the Ashtabula Radio Shack can at least take some solace...
"Researchers at Pacific Northwest National Laboratory,
funded by the U.S. Army Tank Automotive Research, Development an Engineering Center,
have developed a new process for joining aluminum and steel parts with the aim of lightweighting
combat vehicles for more agility and fuel efficiency. The development fills an important
gap, particularly when it comes to joining thick aluminum plates with steel. The DoE's
Vehicle Technologies Office is also examining the technology for automotive applications.
Lab testing found that the joints resulting from the new process, called
friction stir dovetailing
(FSD), are not only stronger, but demonstrate 5 times higher..."
Are you violating patent laws in your basement?
Patent laws have changed since this article was published in 1966, but the tenets are
basically the same - do your due diligence on prior work assignment before publishing
any publicly accessible product (print or physical). Since part of Popular Electronics'
raison d'être is to provide circuits for hobbyists to build and benefit from, the lawyer
who wrote this piece focuses on such applications. He claims, at least according to 1960
patent law, "There are court decisions which hold that experimental use of a patented
invention for the sole purpose of gratifying curiosity or a philosophical taste, or for
mere amusement, is not an infringement." HOWEVER, before you conclude that this must
still be the case, read this synopsis from the Ius Mentis website...
Fairview Microwave, a supplier of on-demand RF
and microwave components, has just introduced a new family of
coaxial surge protectors that were developed to protect wired and wireless
communications equipment from indirect lightning strikes and power surges.
Fairview Microwave's 45 new coaxial lightning and surge protectors were designed
to be used in Wi-Fi networks, active antenna systems, cellular networks, GPS
systems and public safety communications systems. These new high performance RF
coax surge protectors feature VSWR as low as 1.1:1, max power as high as 2kW,
multi-strike capability...
"A joint research team of the Technical University
of Munich (TUM) and the Research Centre Jülich has printed patterns onto gummy bears.
A joke of underchallenged or bored scientists? Certainly not: What looks like gimmickry
at first sight could change medical diagnostics. On the one hand, the scientists around
Prof. Bernhard Wolfrum did not print an image or lettering, but a
microelectrode array.
These components consist of a large number of electrodes and can measure changes
in the electrical voltage in cells. These occur, for example, during the
activity..."
Sunday 24
At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's (6/18 -
6/22) "Tech Industry Headlines" column on the RF Cafe homepage. For the sake of
all the avid cruciverbalists amongst us, each week I create a new
technology-themed crossword puzzle using only words from my custom-created
related to engineering, science, mathematics, chemistry, physics, astronomy,
etc. You will never find among the words names of politicians, mountain ranges,
exotic foods or plants, movie stars, or anything of the sort. You might,
however, see someone or something in the exclusion list who or that is directly
related to this puzzle's theme, such as Hedy Lamar or the Bikini Atoll,
respectively. Enjoy...
Friday 22
I found this
Bridge Circuit Quiz in my stack of vintage Popular Electronics
magazines. Your challenge here is to decide what the main function of each type
of bridge circuit is. Most bridge circuits are designed such that a component of
unknown value is inserted into one of its four branches, and then one or more
variable components of known values are adjusted to balance the bridge and
thereby create a minimum (null) between opposite (circuit-wise) nodes.
Admittedly, I did not fare well, but it is because I do not recall having the
names associated with many of these bridge circuits. Of course nearly everyone
is familiar with the Wheatstone, Kelvin, and Wien bridges. Hyperlinks...
"In the new quantum information technologies,
fragile quantum states have to be transferred between distant
quantum bits. Researchers have now realized such a quantum transmission
between two solid-state qubits at the push of a button. Data transmission is the backbone
of the modern information society, on both the large and small scale. On the internet,
data are exchanged between computers all over the world, most often using fibre
optic cables. Inside a computer, on the other hand, information has to be
shuttled back and forth between different processors. A reliable exchange of
data..."
Perhaps one of the most frustrating situations
to find yourself in if you are a
hard core audiophile is being an unmarried enlisted man in the military, living in
the barracks. Unlike residing in a college dorm where comparatively there is no iron
hand of peaceful existence enforcement to quell a desire for music hall sound levels
with bass saturation that can rock you off your chair (other than dorm mates threatening
to beat you to a pulp), in a military establishment there is an immediate threat of arrest,
rank demotion, monetary fines, or a letter of reprimand (aka nonpunitive
punishment) for blasting a stereo (and your barrack mates might beat you to a
pulp). One guy I shared a USAF barracks room with had a couple thousand dollars
worth of stereo equipment in a 19" rack in the room. It had something like...
Smithsonian magazine's Austin Clemens
created this map (click thumbnail) of the U.S. showing
where the innovation hubs were a century ago compared to now. The occasion is the U.S.
Patent and Trademark Office (USPTO)
processing its ten millionth patent. America's westward expansion during the period is
made obvious by the concentration of black dots (20th century) versus blue dots (21st
century). You will eventually be able to read this online at Smithsonianmag.com
(page 19), but for now you will have to get the magazine
- try your library.
"Researchers have found a way to convert nanoparticle-coated
microscopic beads into lasers smaller than red blood cells. These microlasers, which
convert infrared light into light at higher frequencies, are among the smallest
continuously emitting lasers of their kind ever reported and can
constantly and stably emit light for hours at a time, even when submerged in biological
fluids such as blood serum. These microlasers, which convert infrared light into
light at higher frequencies, are among the smallest continuously emitting lasers
of their kind ever reported and can constantly and stably emit light for hours
at a time...
Thursday 21
Last week I posted Part 2 of this "Know
Your Electronic Chemicals" series which appeared in two 1960 issues of Electronics
World. Fortunately, I was able to obtain the previous edition with Part 1
(the vintage magazines I buy typically sell for $2-$3 apiece on eBay). Many, if
not most, of the chemicals presented in the articles are not used anymore, but
similar types are. Interestingly but typically, almost no emphasis is placed on
the use of protective clothing, goggles, gloves, gas masks, etc. A lot of people
were harmed unnecessarily due to not taking basic precautions, but it just was
not part of normal operating procedure. To be honest, even though I know better,
other than...
"'Our brain is a fantastic computer,' says Professor
Tamalika Banerjee from the University of Groningen in the northern Netherlands. The brain,
after all, has the ability to process vast amounts of information with an energy efficiency
far superior to that of today's computers. By integrating storage, memory, and processing
into one unit, however, Banerjee and fellow physicists at the University of Groningen
hope their semiconductor device someday supports a parallel computing architecture that
rivals the
workings of the brain.
Banerjee's research group studies spintronics..."
Coilcraft has introduced a line of
1:1 coupled
surface mount inductors (aka transformers) with 1,500 Vrms, one minute isolation
(hipot) between windings. Key features include ultra-small package size (8.0 ×
6.4 × 3.5 mm), 13 inductance values ranging from 4.7 to 150 µH, Peak current
ratings up to 2.7 A - a 40% increase over previous generation products, provides
significant size and cost reductions over conventional bobbin-wound
alternatives. Free samples are available...
Ransom Stephens has an interesting article on
the EDN website titled, "Hypnotizing Test Engineers with Figures of Dubious Merit."
Ever increasing specification complexity makes deciding which parameters to test
for and even how to legitimately make the measurements. "Since the dawn of time,
standards documents have specified maximum and/or minimum values for design
parameters to assure product performance and compatibility. Maximum allowed
values for jitter, noise, insertion loss, rise and fall times, minimum
extinction ratios, eye height and eye width. Everywhere you looked, a simple
measurement screamed yay or nay, stay or go..."
The
reflected-beam kinescope (RBK) held high hopes for large video displays with
shallow depths. A traditional cathode ray tube (CRT) is as deep from front to
back as the width of the display, which means, as anyone who has owned a CRT
television or computer monitor knows, a lot of space is required to accommodate
a large display. Evidently the RBK never panned out as a manufacturable product.
Its "inside-out" configuration resulted in a CRT that looks like someone reached
through the front, grabbed the tail end, and pulled it back through the front.
In other 1960 news was a high voltage ferroelectric converter...
"Scientists have synthesized a new cathode material
from iron fluoride that surpasses the capacity limits of traditional
lithium-ion batteries.
As the demand for smartphones, electric vehicles, and renewable energy continues
to rise, scientists are searching for ways to improve lithium-ion batteries -
the most common type of battery found in home electronics and a promising
solution for grid-scale energy storage. Increasing the energy density of
lithium-ion batteries could facilitate the development of advanced technologies
with long-lasting batteries..."
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