Today in Science History -
Here is another of John Comstock's crossword
puzzles from a 1960s issue of Electronics World magazine. His "Name-the-Scientist"
puzzle, as the title suggests, draws mostly on your knowledge of men who are very
familiar to anyone who has been in the electronics game for a while. There are a
few not-a-name words, but they are related to somebody's name. Mr. Comstock
must have been really fond of one guy since he and his invention appear multiple
times in various forms. I have to admit to missing 17 Down, but then at least recognizing
the name after seeing it in the answer key.
"Electronic components face a host of challenges
while in space, from extreme temperature variation to space radiations. These harsh
conditions mean that any Commercial Off-the-Shelf (COTS) component cannot be used
for space missions. The electronic components used in making satellites must be
able to withstand a wide range of environmental challenges - from the complexities
of being launched from Earth to the extremely harsh environment of outer space.
everything RF has compiled a list of 10 trending
space-qualified RF components. Visit the new SPACE HUB on everything RF to keep
up to date with the latest on space-qualified components..."
If you are a collector of vintage high-end
audio equipment, chances are you owned a
reel-to-reel tape player. I remember back in the 1970s that anybody wanting
to call himself an audiophile had better own a rack-mounted reel-to-reel player.
Of course the funny part is that many of those people could not afford to buy original
recordings on tape, so they would dub from an LP on a turntable or from a cassette
or, gasp, 8-track tape. This article from the August 1967 edition of Electronics
World delves into the technical aspects of magnetic tape, daring to introduce such
terms as intrinsic cohesive force, residual induction, and flux - heavy stuff for
the layman. Of course, regurgitating such terms while wowing (pun intended) their
friends with a rolling tape held to keep the subject off of whether the music being
played on a $1000 reel-to-reel player had been dubbed from a $75 cassette deck...
When less efficient coupling is desired,
you can rotate or move the loop until it encircles a smaller number of H lines.
When the diameter of the loop is increased, its power-handling capability also increases.
The bandwidth can be increased by increasing the size of the wire used to make the
loop. When a loop is introduced into a waveguide in which an H field is present,
is induced in the loop. When this condition exists, energy is removed from the
waveguide. Figure 1-40A - Loop coupling in a rectangular waveguide. Slots or apertures
are sometimes used when very loose (inefficient) coupling is desired, as shown in
figure 1-41. In this method energy enters through a small slot in the waveguide
and the E field expands into the waveguide. The E lines expand first across the
slot and then across the interior of the waveguide. Minimum reflections occur when
energy is injected or removed if the size of the slot is properly proportioned to
the frequency of the energy...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Stencils available 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). Stencils 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...
Berkeley Nucleonics Corporation (BNC) is
a leading manufacturer of precision electronic instrumentation for test, measurement,
and nuclear research. Founded in 1963, BNC initially developed custom pulse generators.
We became known for meeting the most stringent requirements for high precision and
stability, and for producing instruments of unsurpassed reliability and performance.
We continue to maintain a leadership position as a developer of custom pulse, signal,
light, and function generators. Our designs incorporate the latest innovations in
software and hardware engineering, surface mount production, and automated testing
Here is yet another report on the work done
by Bell Telephone
Laboratories to advance the science of telecommunications. By 1945 when this
appeared in Radio News magazine, Bell Labs had already been experimenting with coaxial
cable as a means of transmission for broadband voice, facsimile, and video signals.
In fact, it claims coax was used as early as 1927 to connect New York City to Washington,
D.C., and that a new loopback system simulating a 3,800-mile run was being tested
between New York City and Philadelphia. Microwave relay stations* were also in their
infancy at the time, so investigations into both modes of long distance transmission
were being explored. It is too bad the company got overzealous and abused the customers
who funded their success, resulting in a court-ordered breakup of the monopoly in
1974. Of course company managers and lawyers quickly figured out a way to restructure
the "Baby Bells" in a manner which, taken in totality...
"A new study by engineers at MIT, Caltech,
and ETH Zürich shows that 'nanoarchitected' materials - materials designed from
precisely patterned nanoscale structures - may be a promising route to
lightweight armor, protective coatings, blast shields, and other impact-resistant
materials. The researchers have fabricated an ultralight material made from nanometer-scale
carbon struts that give the material toughness and mechanical robustness. The team
tested the material's resilience by shooting it with microparticles at supersonic
speeds, and found that the material, which is thinner than the width of a human
hair, prevented the miniature projectiles from tearing through it..."
There was a time when we did not take the
availability and abundance of everything for granted. Most of us have parents or
grandparents who were around during World War II that can tell stories of ration
stamps for certain food and clothing items, fuel, tires, and other things. I have
a few given to me by my grandfather. Many industries, including electronics manufacturing,
were strongly encouraged or required to dedicate all efforts toward war production.
Crosley Corporation, based in Cincinnati, Ohio, was no exception. A notice of Crosley
abandoning their 1943 line of commercial radios to make way for military radios
appeared in the September 1942 edition of Radio-Craft magazine. This is of particular
interest to me since I just completed the restoration of a 1941 vintage
Crosley 03CB floor console radio. It means I probably have one of the last pre-war
models of a Crosley radio...
ARCTURUS is the new
flexible antenna for 5G/4G LTE/3G/2G/NB-IoT/CATM applications designed by Synzen
Precision Technology. In today's tech and electronics world, where the modern mantra
is to think bigger and make smaller, we've designed perhaps the most compact and
versatile 5G FPC antenna on the market. Measuring just 88 mm x 14 mm,
ARCTURUS can be placed internally in devices which require an integrated antenna
solution. Its ultra-small form factor doesn't compromise on performance, covering
a hugely impressive array of wideband frequencies from 617-5000 MHz. Arcturus
can be easily integrated with its "peel and stick" self-adhesive backing...
The velocity of propagation of a wave along
is less than its velocity through free space (speed of light). This lower velocity
is caused by the zigzag path taken by the wavefront. The forward-progress velocity
of the wavefront in a waveguide is called Group Velocity and is somewhat slower
than the speed of light. The group velocity of energy in a waveguide is determined
by the reflection angle of the wavefronts off the "b" walls. The reflection angle
is determined by the frequency of the input energy. This basic principle is illustrated
in figures 1-28A, 1-28B, and 1-28C. As frequency is decreased, the reflection angle
decreases causing the group velocity to decrease. The opposite is also true; increasing
frequency increases the group velocity. The waveguide analyzed in the previous paragraphs
yields an electric field configuration known as the half-sine electric distribution...
It was a lot of work, but I finally finished
a version of the "RF & Electronics Schematic & Block Diagram Symbols" that
works well with Microsoft Office™ programs Word™, Excel™, and Power Point™.
This is an equivalent of the extensive set of amplifier, mixer, filter, switch,
connector, waveguide, digital, analog, antenna, and other commonly used symbols
for system block diagrams and schematics created for Visio™. Each of the 1,000 or
so symbols was exported individually from Visio in the EMF file format, then imported
into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or
down without becoming pixelated, so all the shapes can be resized in a document
and still look good. The imported symbols can also be UnGrouped into their original
constituent parts for editing. Check them out!
LadyBug Technologies was founded in 2004
by two microwave engineers with a passion for quality microwave test instrumentation.
Our employees offer many years experience in the design and manufacture of the worlds
best vector network analyzers, spectrum analyzers, power meters and associated components.
The management team has additional experience in optical power testing, military
radar and a variety of programming environments including LabVIEW, VEE and other
languages often used in programmatic systems. Extensive experience in a broad spectrum
of demanding measurement applications. You can be assured that our Power Sensors
are designed, built, tested and calibrated without compromise.
By June of 1945 when this "Postwar
Plans for the Radio Dealer" article appeared in Radio News magazine, Germany
had unconditionally surrendered at Reims, France. Japan was still holding out for
an unlikely victory and prepared for a massive Allied landing on their homeland
with the likely loss of millions of souls, but most people could feel that the end
of World War II was imminent. Accordingly, trade magazines of the day ran many
pieces discussing potential options for out-of-work servicemen. Vast amounts of
knowledge and experience had been gained in the previous half a decade, and it was
to be put to good use. Lots of men left their jobs and businesses behind for the
sake of saving the free world, and were anxious to pick up...
"Researchers at the National Institute of
Standards and Technology (NIST) and Wavsens have developed a method for using
radio signals to create real-time images and videos of hidden and moving objects,
which could help firefighters find escape routes or victims inside buildings filled
with fire and smoke. The technique could also help track hypersonic objects such
as missiles and space debris. The new method, described June 25 in Nature Communications,
could provide critical information to help reduce deaths and injuries. Locating
and tracking first responders indoors is a prime goal for the public safety community.
Hundreds of thousands of pieces of orbiting space junk are considered dangerous
to humans and spacecraft..."
That portion of the electromagnetic spectrum
which falls between 1000 megahertz and 100,000 megahertz is referred to as the
region. Before discussing the principles and applications of microwave frequencies,
the meaning of the term microwave as it is used in this module must be established.
On the surface, the definition of a microwave would appear to be simple because,
in electronics, the prefix "micro" normally means a millionth part of a unit. Micro
also means small, which is a relative term, and it is used in that sense in this
module. Microwave is a term loosely applied to identify electromagnetic waves above
1000 megahertz in frequency because of the short physical wavelengths of these frequencies.
Short wavelength energy offers distinct advantages in many applications...
"These eyes in the sky fly above drones
and below satellites. Alphabet's enthusiasm for balloons deflated earlier this year,
when it announced that its high-altitude Internet company, Loon, could not become
commercially viable. But while the stratosphere might not be a great place to put
a cellphone tower, it could be the sweet spot for cameras, argue a host of high-tech
startups. The market for Earth-observation services from satellites is expected
to top US $4B by 2025, as orbiting cameras, radars, and other devices monitor crops,
assess infrastructure, and detect greenhouse gas emissions. Low altitude observations
from drones could be worth.
Balloons in the stratosphere, 20 kilometers above Earth (and 10 km above most
jets), split the difference..."
By adding several shunt resistors in the
meter case, with a switch to select the desired resistor, the ammeter will be capable
of measuring several different maximum current readings or ranges. Most meter movements
in use today have sensitivities of from 5 microamperes to 1 milliampere. Figure
1-22 shows the circuit of meter switched to higher ranges, the shunt an
that uses a meter movement with a sensitivity of 100 microamperes and shunt resistors.
This ammeter has five ranges (100 microamperes; 1, 10, and 100 milliamperes; 1 ampere)
selected by a switch. With the switch in the 100 microampere position, all the current
being measured will go through the meter movement. None of the current will go through
any of the shunt resistors...
As with just about every other type of hobby
anymore, creativity and mechanical aptitude is not much of a necessity if you have
money to spend. There is such a plethora of options available for every conceivable
need to satisfy whatever degree of complexity you want your hobby to entail. The
back third of every edition of the ARRL's QST magazine is loaded with advertisements
offering antennas, radios, towers, test equipment, guy wires, insulators, cables,
connectors, soldering stations, semiconductors, tubes, nuts and bolts. It is a wonderful
world we live in if your desire is to engage in the operational aspect of a hobby
rather than the building and experimenting aspects. It was not always so. Half a
century ago the average hobbyist needed to scrounge for
components that could be "repurposed" for use as needed. Sure, there were many
sources for common components then, but even if they were available, hobbyists either
could not afford them...
Radio Theme Crossword Puzzle for July 25th has many words and clues related
to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics,
and other technical subjects. As always, this crossword contains no names of politicians,
mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless
it/he/she is related to this puzzle's technology theme (e.g., Reginald Denny or
the Tunguska event in Siberia). The technically inclined cruciverbalists amongst
us will appreciate the effort. Enjoy --- This one is going to take a while!