Here is a quick
Hi−Fi Quiz for all you
audiophiles out there. Although it appeared in a 1955 issue of Radio &
magazine, save for question #10 all of Q's and A's still apply to today's
equipment. Even that one can be easily guessed. Q4 might seem a bit foreign, but
think of the "groove" type as applying to 78, 45, or 33-1/3 rpm platters and
you'll do OK. Question #7 could be a baffler (pun intended - you'll see how)
were it not for one obviously invalid option that it takes an RF guy (or gal) to
recognize its inanity. Good luck. BTW, I missed Q1, but should have known
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. The company is
a leader in development and production of the films required for these type of RF/microwave
components. Please check out Res-Net Microwave's website to see how they can help
with your current project.
"Failure is an integral part of the engineering
experience. It is so common that it has become an expectation and even affectionately
referred to as Murphy's Law: 'Anything that can go wrong will go wrong.' It has
been stated that the great American inventor Thomas Edison was once asked by a reporter
how it felt to fail 700 times in the creation of the light bulb. His response: 'I
have not failed 700 times. I have not failed once. I have succeeded in proving that
those 700 ways will not work. When I have eliminated the ways that will not work,
I will find the way that will work.' Henry Petroski, the famous American engineer
failure analysis, wrote the following in his book, To Engineer Is Human: The
Role of Failure in Successful Design: 'I believe that the concept of failure..."
Development of the
during World War II helped change the destiny of Allied forces through
using high frequency
radar with enough power to detect distant targets while using frequencies which
were out of the normal detection
bands of Axis forces' receivers. Most equipment at the time could not operate
efficiently (or at all) above a few hundred MHz. It was considered a top-level secret
with great concern that the technology not fall into the hands of German and
Japanese scientists. According to this early post-war advertisement in a 1945
issue of Radio News, Bell Labs was totally consumed by the development of magnetrons, and
was relieved to finally be able to boast of its critical role now that the war
Technologies is transforming the Test and Measurement Industry. Our premium
line of products includes digital and mixed signal oscilloscopes, spectrum analyzers,
function / arbitrary waveform generators, programmable power supplies and loads,
digital multimeters, data acquisition systems, and application software. Our test
solutions combine uncompromised product performance, quality, and advanced product
features; all delivered at extremely attractive price points. This combination provides
our customers with unprecedented value for their investment, reduces their overall
cost of test, and helps speed time to completion of their designs or projects.
Times Microwave Systems, a pioneering brand
in innovative RF and microwave interconnect assemblies, cables and connector design,
announces the addition of a new
1/2" plenum RF cable to its product line. The LPA-500 LLPL air-dielectric corrugated
plenum cable is a low-loss, plenum listed (type CMP) coaxial cable. Available now,
its design offers excellent intermodulation performance, and can be used as feedlines
within buildings to support distributed antenna systems (DAS); public safety communications
systems; RF backbone interconnects within plenum airspaces; and additional applications.
The LPA-500 LLPL is an affordable option that provides the quality and performance
for which Times is universally recognized. The new 1/2" plenum RF cable...
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.
Radio-Electronics October 1953 Circuit Symbol Stamp p126
Comics June 1951 Radio-Electronics
RF Cafe typically receives 8,000-15,000
website visits each weekday and about half that on weekends.
RF Cafe is a favorite of engineers, technicians, hobbyists, and students all
over the world. With more than 13,000 pages in the Google search index,
RF Cafe returns in favorable
positions on many types of key searches, both for text and images. New content
is added on a daily basis, which keeps the major search engines interested enough
to spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. I also re-broadcast homepage
items on LinkedIn. If you need your company news to be seen, RF Cafe is the
place to be. Advertising begins at $40/month.
RF Cascade Workbook 2018 is the next phase in the evolution
of RF Cafe's long-running series, RF Cascade Workbook. Chances are you
have never used a spreadsheet quite like this. It is a full-featured RF system cascade
parameter and frequency planner that includes filters and mixers for a mere $45.
Built in MS Excel, using RF Cascade Workbook 2018 is a cinch and
the format is entirely customizable. It is significantly easier and faster than
using a multi-thousand dollar simulator when a high level system analysis is all
that is needed. An intro video takes you through the main features...
With more than 1000
custom-built symbols, this has got to be the most comprehensive set of
Visio Symbols 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). Symbols 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...
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers"
Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's"
design has been ripped off by other people and used on their products, so please
be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢ per
item - Cafe Press gets the rest of your purchase price. These would make excellent
gifts for husbands, wives, kids, significant others, and for handing out at company
events or as rewards for excellent service. It's a great way to help support RF
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. 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...
"The dangers of lithium-ion batteries, like
those used in smartphones and electric vehicles (EVs), catching fire or exploding
has been well-publicized. But the true impact of an EV battery catching fire and
the dangers that could result aren't known on a wide scale, which remains a question
mark as they become more widely adopted. To find out, researchers in Switzerland
EV batteries on fire in a series of experiments to test the potential for damage
and disaster in the case of EVs catching fire in parking structures or a tunnel.
What they discovered is that while in some cases, electric vehicle battery fires
are no more dangerous than other types of car fires, the smoke and soot they give
off contains toxic metal oxide "
"It's amazing how many iconic and forgotten
radio telescopes pop-up in movies, TV shows, and documentaries. The human eye
was our first space image detector. On a beautifully clear night at the Aoraki Mackenzie
International Dark Sky Reserve in New Zealand with the Milky Way displayed above
us, we can see about 5,000 stars. But to really see - that is, to detect and communicate
into space - a radio telescope is needed. Such devices can receive radio waves from
astronomical sources in the sky and are the main observing instrument used in radio
astronomy. Whereas optical telescopes study the light wave portion of the spectrum,
radio telescopes focus on the radio frequency portion of the electromagnetic (EM)
spectrum emitted by almost all astronomical objects..."
"Electronics engineers continually look for
better insulating materials to use in their projects. Finding the right ones leads
to a longer product lifespan, along with improved performance and reduced heat during
use. Over the last several years, researchers have achieved particularly promising
results while using boron nitride to insulate electronics.
Boron nitride is a synthetic ceramic material available in solid and powder
forms. Since it has a similar microstructure to graphite, some people refer to it
as 'white graphite.' Unlike graphite, boron nitride performs well as an electronics
insulator with a higher oxidation temperature than that material. Scientists are
working hard to test and verify boron nitride's usefulness as an electronics insulator..."
"A research team led by University of Buffalo
has developed a new
3D-printed molecular ferroelectric metamaterial. The advancement has been published
in the Proceedings of the National Academy of Science and is a step toward making
these extraordinary lab-created materials more affordable and adaptable to countless
multifunctional technologies. It could benefit everything from acoustic blankets
for aircraft soundproofing to shock absorbers and elastic cloaks that shield sensitive
electronic systems from external mechanical disturbances. A metamaterial is any
material engineered to have a property that is not found in naturally occurring
materials. Ferroelectricity relates to crystalline substances that have spontaneous
electric polarization that's reversible by an electric field..."
"Despite a lot of progress in recent years,
practical laser weapons that can shoot down planes or missiles are still a ways
off. But a new
liquid laser may be bringing that day closer. Much of the effort in recent years
has focused on high-power fiber lasers. These lasers usually specially doped coils
of optical fibers to amplify a laser beam, and were in originally developed for
industrial cutting and welding. Initially, fiber laser were dark horses in the Pentagon's
effort to develop electrically powered solid-state laser weapons that began two
decades ago. However, by 2013 the Navy was testing a 30-kilowatt fiber laser on
a ship. Since then, their ability to deliver high-energy beams of excellent optical
quality has earned fiber lasers the leading role in the current field trials of
laser weapons in the 50- to 100-kilowatt class. But now aerospace giant Boeing has
teamed with General Atomics..."
"As the semiconductor industry witnesses
the winding down of the expectation that the number of transistors that can be shoehorned
into silicon microchips will double every couple of years, researchers are coming
up with new ways to keep the effect of Moore's Law rolling along. One such method
with exciting prospects employs
liquid metals to produce two-dimensional semiconducting materials with atomic-scale
thickness. This enables the creation of a transistor channel between source and
drain that is almost an order of magnitude thinner than those employed in silicon
transistors. In addition, they possess intriguing properties such as a variety of
band gaps and carrier concentrations, as well as unique transducing properties.
“The two-dimensional confinement of free charge-carriers..."
"Engineering students at the University of
Cincinnati are building tiny custom CubeSat
satellites to test the radiation shielding properties of carbon fiber material
and take high-resolution photos of the Great Lakes from space. LEOPARDsat-1 will
record how much radiation from space seeps through different thicknesses of carbon-polyethylene
samples. HABsat1 relies on an internal flywheel system in which motor-driven spinning
flywheels can orient a satellite on three axes..."