See Page 1 |
2 |
3 |
4 | of the November 2023 homepage archives.
Tuesday the 21st
Dubiously attributed to carnival showman
P.T. Barnum, the saying that "There's a sucker born every minute" seems to have
been the case since the beginning of time. Recall that Adam ate of the apple pitched
by Eve, shortly after she had been beguiled by the serpent. Things went downhill
from there. Spies engaged in espionage have also been in plentiful supply throughout
the history of mankind. Amongst other things, they procure ideas conjured up by
other men's minds by hook or by crook, then use that knowledge themselves or sell
it to interested parties - who often solicited the services of the spy in the first
place. Most acts of deceit and trickery are carried out in secret, out of public
view; however, sometimes the perpetrators of cunning and wile boldly exercise their
craft in the open. Such was (is) the case of many (maybe most) offers to assist
garage, basement, backyard, attic, etc., inventors in
obtaining a patent for their inventions. Promises of fame and/or fortune are
purchased for the paltry sum of a few hundred dollars (thousands, today). Magazines
such as Popular Mechanics (to wit this May 1943 issue), Science and
Mechanics, and Mechanix Illustrated, all of which appeal(ed) to fathers,
husbands, sons, boyfriends - and even some girls - were loaded with advertisements
by companies making such offers. Stories abound...
"It's on
of the most terrifying events imaginable. There have been over 50 recent reports
of frightening cyberattacks that have altered planes' in-flight GPS, leading to
what experts described as 'critical
navigation failures' onboard the aircraft. More frightening still, industry
leaders thought that this type of hacking was not possible and are at a loss over
how to fix the now glaring security failure. Since late August, they have been observed
throughout the Middle East, particularly over Israel, neighboring Egypt, and Iraq.
In September, the FAA issued a warning on the 'safety of flight risk to civil aviation
operations' over the spate of attacks, according to OpsGroup, an international collection
of pilots and technicians who first brought attention to the terror. The attack,
called GPS spoofing - when a navigation system is given counterfeit coordinates...
Electronically steered phased arrays have
largely replaced mechanically steered antennas in the last couple decades. In an
effort to eliminate the need for a waveguide rotary joint, which is both expensive
and complex when built for high reliability under harsh operating conditions, Japanese
engineers developed an alternative where a small subreflector is orbited about a
central axis to produce a small scanning angle. Their efforts are presented in this
1964 issue of Electronics magazine. The measured half power bandwidth of the central
beam was about 7.5°, while the half power scan width about the main axis boresight
appears per one of the plots to be around 30° or so (if I interpret it correctly).
I assume this scheme was never pursued much beyond the experimental phase since
it does not seem to be a current standard.
"The quantum computers that IBM, Google,
Amazon, and others are developing face daunting challenges on the road to practical
applications. Now it turns out that they may face a fundamental limit to large-scale
performance - the
imperfect nature
of all clocks. Quantum computing can theoretically find answers to problems
that classical computing would take eons to solve. The more components known as
quantum bits, or qubits, that a quantum computer links together, the more basic
computations known as quantum gates it can perform. Whenever a quantum computer
performs an operation, it has to expose its components to very specific forces for
a very specific amount of time, explains study lead author Jake Xuereb, a quantum
physicist at the Vienna University of Technology. Therefore, accurate timekeeping
is critical. However, perfect clocks don't exist. The researchers note that every
clock has two key properties..."
Here is another one of those advertisements
that you would probably never see in today's electronics magazines, but its theme
was fairly prevalent up through about the 1970s. There is fundamentally nothing
offensive about it; men have always endeavored to gain the favor of women. However,
society has since been bullied by name-calling, finger-pointing, full-of-themselves
celebrities and media into being afraid to acknowledge innate, harmless propensities
of everyday people. The natural has been declared unnatural and nonbelievers must
be reprogrammed to not just tolerate, but to encourage and facilitate counterintuitive
concepts. Anyway, note the rather strained attempt at wordplay with the "Uniform
Resistance" theme for pitching P.R. Mallory's carbon potentiometers. Get
it? The dame is offering resistance to the swabbie in uniform. This is akin
to the "Radio Term Illustrated" comics that ran in Radio-Craft magazine
in the era...
Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 280,000 times per year! 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. If you need your company news to be seen, RF Cafe is the
place to be...
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
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seeking distributors, so please contact us if interested. Visit Centric RF today.
Monday the 20th
Have you ever watched an animated video
of how the
differential joint in a car or truck works? Its simplicity required a spark
of genius to come up with. The wheels on the inside of a turn need to turn at a
lesser rate than those on the outside. Recall that for a fixed rotational rate, ωturn
(rad/s), about a pivot point (the center of the turn) and a distance, ωturn,
from the pivot point, the radial speed, sturn, is ωturn*rturn.
Since ωturn is the same for all points along
the radial, sturn is a linear function of rturn.
Assuming the tires are of equal diameter, dtire (or rtire),
the rotational rate, ωtire, of each wheel is sturn/
rtire. Without a differential gear system, then, the
wheels on the inside and outside of a turn would skid due each needing to rotate
at a different rate, but being forced to turn at the same rate. If a picture is
worth 1,000 words, then this video is worth many times more than that. Here is a
great animation of how a differential gear works. Be sure to also watch the limited
slip differential video as well. What about electric vehicles with independent drive
motors on the wheels? The computer systems takes care of sensing the rotational
speed and torque requirements for each wheel. Analog versus digital. Like Joe Walsh
of the Eagles, I'm an analog guy.
Given
that today, November 20th, is the anniversary of Microsoft's introduction of the
first version of Windows, you might want to view this history of its various versions
(see today's RF Cafe logo in the upper left). Notice I didn't call it the Windows
Operating System, because it was not an OS; it rode on top of DOS. The first version
of Windows I recall using was 2.0, on someone else's computer. The first version
I owned was 3.0, residing on my Packard Bell computer. Love it or hate it, and yes,
Windows has caused many headaches over the years, but there really has been no other
environment with a larger user base and software base - at least for desktops. There
are many History of Windows
videos to choose from, but this one is fairly short and is narrated, rather than
having annoying synthesized music playing in the background. Enjoy!
Each month, the American Radio Relay League's
(ARRL's) QST magazine runs a feature called "Member Spotlight." Usually, the person
being paid homage is a non-celebrity who has done remarkable work to promote Ham
radio. Occasionally, a well-known celebrity type gets the honor, as is the case
with the December 2023 issue's personality,
Joe Walsh (WB6ACU), who has been the lead guitarist with the Eagles rock band
since the mid-1970s. Joe earned his license waaaay back in the year 1960, when Morse
code proficiency was a requirement. In the articles he states, "I'm an analog
guy. I like knobs more than a mouse." Many older Hams share the sentiment. Having
spent my teenage years in the 1970s, I am of course very familiar with the Eagles
and the name Joe Walsh. Don Henley, though, is probably the name most associated
with the Eagles...
Radio-Craft magazine founder, editor,
and publisher Hugo Gernsback wrote this piece in the Fall after the United States
officially entered into World War II. I say officially because to some extent
we were participating for many months prior to the Japanese attack at Pearl Harbor
on December 7, 1941. Recall how FDR justified his March 1941
Lend Lease Act by comparing the action to lending your hose to a neighbor whose
house was burning. We were providing equipment and training to Allied nations in
Europe almost immediately after Hitler's army invaded Czechoslovakia in 1939. The
Army Air Corps had the famous Flying Tigers squadron defending southern China against
Japanese bombing attacks as early as April of 1941. Electronics communications,
which made great advancements during WWII, played a major role in the ultimate Allied
victory...
"Scientists
have discovered what they say is the
fastest and most efficient semiconductor
yet. Although the new material is made using one of the rarest elements on Earth
(rhenium), the researchers suggest counterparts made from more abundant materials
may be discovered that operate comparably fast. Semiconductors underpin virtually
all modern electronics. However, as commonplace as they've become, semiconductors
still face constraints when it comes to their speed. One reason for these speed
limits has to do with atomic vibrations, which travel as quasiparticles known as
phonons within solid materials. Phonons can scatter the particles that carry energy
and information around electronics. These are typically electrons, but are sometimes
more exotic particles, such as excitons (electrons bound to their positively charged
quasiparticle counterparts, electron holes)..."
This schematic and service data is evidently
updated information for an earlier one, number 138. That Radio Service Data Sheet,
originally published in the May 1935 issue of Radio-Craft magazine, is
included below. Only voltage changes in U6 follow 100; V4. Data Sheet No. 138. The
earlier version had chassis models U6-D1 and U6-D2, and this one adds chassis U6.
A quick comparison of the schematics does not reveal an changes in component values.
Maybe a reader wrote in asking for the U6 version. As mentioned in other instances,
most manufacturers did not make schematics and alignment documentation available
to laymen, only authorized dealers and service shops, so this was the only may most
people could get information needed to work on their own radio sets. A nicely restored
example of the
Emerson Model 38 was found...
RF Cascade Workbook 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 (click here for screen capture). 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...
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!
Sunday the 19th
This custom RF Cafe
electronics-themed crossword puzzle for November 19th contains words and clues
which pertain exclusively to the subjects of electronics, science, physics, mechanics,
engineering, power distribution, astronomy, chemistry, etc. If you do see names
of people or places, they are intimately related to the aforementioned areas of
study. As always, you will find no references to numbnut movie stars or fashion
designers. Need more crossword RF Cafe puzzles? A list at the bottom of the page
links to hundreds of them dating back to the year 2000. Enjoy.
One aspect of advertising on the RF Cafe
website I have not covered is using
Google AdSense.
The reason is that I never took the time to explore how - or even whether it is
possible - to target a specific website for displaying your banner ads. A couple
display opportunities have always been provided for Google Ads to display, but the
vast majority of advertising on RF Cafe is done via private advertisers. That is,
companies deal with me directly and I handle inserting their banner ads into the
html page code that randomly selects and displays them. My advertising scheme is
what the industry refers to as a "Tenancy Campaign," whereby a flat price per month
is paid regardless of number of impressions or clicks. It is the simplest format
and has seemed to work well for many companies. With nearly 4 million pageviews
per year for RFCafe.com, the average impression rate per banner ad is about 280,000
per year (in eight locations on each page, with >17,000 pages). That's pretty
good exposure for $300 per month. Some companies have expressed an interest in being
able to manage their advertising accounts themselves a la the Google AdSense program...
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. 50 Ω and 75 Ω models are available, along with
a full line of precision calibration and connector adaptors.
Friday the 17th
When you see an article title such as this
one from at 1947 issue of Popular Science magazine titled "Electronic
Color Television is Here," you might think well duh, what other kind of TV would
there be other than "electronic?" If you had been around at the time and were aware
of developments in color television, you would know that there were a couple variations
of electromechanical systems being considered. In fact, RCA and CBS had a rotating
color wheel (red, green, and blue segments) which rotated in front of the video
detector tube to separate colors for comprising the composite signal, and then a
similar setup for projecting onto a display screen. Fortunately, the all-electronic
NTSC format won the competition. Even so, because of complexity and reliability
concerns, the color TV cameras that flew on Apollo 10 and Apollo 11 (the first moon
landing) in 1969 used the color wheel approach. The RCA scheme reported here uses
stationary mirrors, which went away before the NTSC standard became law...
"Researchers have developed a 'micro
heat engine' that challenges the Carnot limit by achieving high efficiency and
power at the microscopic level. This engine, which operates on a single colloidal
particle directed by a laser beam and manipulated by an electric field, exhibits
efficiency near 95% of the Carnot limit. This advance overturns long-held beliefs
that high power and high efficiency are mutually exclusive due to the power-efficiency
tradeoff, and it could lead to the development of more energy-efficient devices
in the future. Designing a heat engine capable of producing maximum power while
maintaining maximum efficiency has long been a significant challenge in physics
and engineering. Practical heat engines are constrained by a theoretical limit to
their efficiency, known as the Carnot limit, which sets a cap on how much heat can
be converted to useful work..."
When this story was published in 1938 in
Radio-Craft magazine, India was a country of roughly 2 million square miles,
while the 48 United States had about 3.1 million square miles. Radio station growth
in the U.S. already had a three-decade head start in establishing a nationwide network
of broadcast and receiving stations. Manufacturing of the required equipment was
well established within our borders. India, by contrast, relied heavily on outside
sources for equipment and the training of operators and servicemen. The U.S. never
has had and still does not have an official "state radio" as was
All-India Radio. A nice feature of the system was inclusion of a time-keeping
signal that would allow anyone within the reception of a clear signal to synchronize
clocks. The included map shows where the first four 10 kW main shortwave transmitters
were installed in key population areas. The terms "direct-ray" and "indirect-ray"
were used at the time to describe non-skip and atmospheric skip, respectively, propagation.
The newest release of RF Cafe's spreadsheet
(Excel) based engineering and science calculator is now available -
Espresso Engineering Workbook™. Among its many others, there is now a Power
Factor Calculator. RF Cafe Espresso Engineering Workbook™ is
provided at no cost,
compliments of my generous sponsors. The original calculators are included, but
with a vastly expanded and improved user interface. Error-trapped user input cells
help prevent entry of invalid values. An extensive use of Visual Basic for Applications
(VBA) functions now do most of the heavy lifting with calculations, and facilitates
a wide user-selectable choice of units for voltage, frequency, speed, temperature,
power, wavelength, weight, etc. In fact, a full page of units conversion calculators
is included. A particularly handy feature is the ability to specify the the number
of significant digits to display. Drop-down menus are provided for convenience.
Now that a more expandable basis has been created, I plan to add new calculators
on a regular basis...
"Use
it up... Wear it out... Make it do... Or do without." - what a great slogan!
It was coined by the War Advertising Council during World War II to promote
the dual need to conserve scarce resources and to help keep prices down by not generating
excess demand. Most of us have seen videos or read articles about neighborhood materials
collection efforts to round up old tires, scrap metal, glass, tools, electronics
equipment, cloth and clothing, and many other items that could be recycled for use
directly in the war effort. Melanie and I pretty much live by the philosophy. We
keep purchases to a minimum (except for a few toys), and keep clothes, tools, furniture,
etc., until they cannot be repaired anymore, and buy used where practical. No we
are not hoarders. Everything we own will fit in a single U-Haul truck, and believe
me, after having moved more than a dozen times in 30 years, we know how much stuff
we own. Our house is only 920 ft2 with a 1-car garage and an unfinished
basement...
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We
Are the World's Matchmakers" Smith chart design. These would make excellent
gifts for husbands, wives, kids, significant others, and for handing out at company
events or as rewards for excellent service. My graphic has been ripped off by other
people and used on their products, so please be sure to purchase only official RF
Cafe gear. I only make a couple bucks on each sale - the rest goes to Cafe Press.
It's a great way to help support RF Cafe. Thanks...
KR Electronics has been designing and manufacturing
custom filters for military and commercial radio, radar, medical, and communications
since 1973. KR Electronics' line of filters includes lowpass, highpass, bandpass,
bandstop, equalizer, duplexer, diplexer, and individually synthesized filters for
special applications - both commercial and military. State of the art computer synthesis,
analysis and test methods are used to meet the most challenging specifications.
All common connector types and package form factors are available. Please visit
their website today to see how they might be of assistance. Products are designed
and manufactured in the USA.
Thursday the 16th
In the early days of radio, many people
built their sets from schematics and a box full of parts. Often, obtaining the required
components was not such an easy task, either because of a lack of means of knowing
what was available from suppliers or due to lack of availability of needed parts
that were advertised as being ready for purchase. A lot of local electronics repair
shops sold components, as did many hardware stores. Still, fabrication of one's
own inductors, antennas, tuning capacitors and/or coils, chassis for mounting all
the components, etc., was required. Accordingly, science and electronics magazines
often ran a monthly feature presenting
hints, kinks, tricks, and shortcuts submitted by readers. The December 1937
issue of Popular Mechanics magazine published this collection of "hints" which included
a homemade filter for blocking interference from appliances with electrically noisy
motors (arcing from armature brushes) and a means of isolating a possibly hot chassis
from the power source. Poor design and the lack of polarization on AC plugs meant
there was a 50-50 chance the metal chassis would be "hot." The plan for a wind-powered
generator could easily be something seen in a contemporary magazine. Back in the
day, many rural locations had no commercial electric service and relied on wind
and water turbines to provide power to household and farm implements...
In the early 1960's, the U.S. Air Force's
Air Defense Command began installing high power
AN/FPS-24 long range radar units in some of the country's major seaboard and
northern cities. Designed to watch for ICBM's and intruding long-range aircraft
from the U.S.S.R., it operated in the VHF band at a 7.5 MW peak power output.
Once operational, nearby residents immediately began lodging complaints about severe
bleeps of interference on radios (AM, FM, mobile radio, wireless surveillance) and
television that occurred once every 12 seconds - the rotation period of the radar's
120-foot-wide by 50-foot-tall antenna. The USAF's response was to blame the problem
on crappy receiver design by all the manufacturers, and refused to take any action
to mitigation the problem. Many science and engineering magazines reported on the
heated battle, and eventually the government was forced to yield...
"The
B-21 Raider took its first test flight on Friday, moving the futuristic warplane
closer to becoming the nation's next nuclear weapons stealth bomber. The Raider
flew in Palmdale, California, where it has been under testing and development by
Northrop Grumman. The Air Force is planning to build 100 of the warplanes, which
have a flying wing shape much like their predecessor the B-2 Spirit but will incorporate
advanced materials, propulsion and stealth technology to make them more survivable
in a future conflict. The plane is planned to be produced in variants with and without
pilots. 'The B-21 Raider is in flight testing,' Air Force spokeswoman Ann Stefanek
said. Such testing is a critical step in the campaign to provide 'survivable, long-range,
penetrating strike capabilities to deter aggression and strategic attacks against
the United States, allies, and partners..."
You just never know what names you will find
in vintage electronics magazines. Incredibly - assuming of course that this is who
it likely is - I ran across
Steve Wozniak (aka "Woz"), later to be co-founder of Apple Computer, in this
November 1966 issue of Popular Electronics. "Woz" first met Steve Jobs
five years later in 1971 while working at Hewlett Packard. If this is "Woz," he,
having been born in 1950, would have been a 16 year-old high schooler when his entry
was published. The article does not specify who is responsible for which quote.
Woz was a Ham radio guy, so maybe one of the Off the Air comments was from him.
My favorite implausible comment from Sequel 2 is this one: Don't waste money
on 5 amp fuses - buy 15 or 20 amp fuses - they cost the same and you get more fuse
for your money...
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...
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 267,269 products from more than 1397
companies across 314 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.
Wednesday the 15th
Prior to the International Geophysical Year
(aka IGY, which ended up running for a year and a half), spanning from July 1, 1957,
through December 31, 1958, not a lot was known about the upper atmosphere. May 1946,
when this article appeared in Popular Science magazine, was less than a
year after the end of World War II. During the war a lot was learned about
long distance wireless (radio) communications between and across continents and
ship to shore. Scientists theorized about the phenomenon of
charged particles at high altitudes which, being electrically conductive, could
reflect electromagnetic signals so that over the horizon signals could be exchanged.
Coincidence with sunspot activity and aurorae had already been established, but
more knowledge was needed. Rocket technology also developed during the war had matured
to where instruments could be launched tens of mile high into what came to be called
the ionosphere. The Army's WAC Corporal sounding rocket was one of the earlier platforms
for such work...
If you think controversial and otherwise
inane decisions made by high-level courts is something new to this era of political
high dudgeon, think again. This article in the January 1935 in Radio-Craft
magazine reports a Supreme Court decision over who was the
inventor of regeneration in radio circuits - Dr. Lee de Forest or
Major Edwin H. Armstrong. Evidently in spite of much support by the opinions
of notable experts in the field who claim Armstrong deserves credit, the Court found
in favor of de Forest. The battle had been fought at many levels for the previous
18 years. Columbia University's Professor Michael I. Pupin wrote, "On several occasions
after that I have had conversations with de Forest which convinced me that
he did not know of or understand the production of radio frequencies by vacuum tubes."
Major Armstrong eventually committed suicide over his distraught state over this
and other issues...
"Researchers based mainly in Japan report
'the first achievement in hetero-epitaxial growth of β-Ga2O3 thin films on
single-crystalline diamond (111) wafers using RF magnetron sputtering.' While
β-Ga2O3 is a promising new material for extreme-condition electronics, it suffers
from a low thermal conductivity. Growing Ga2O3 on high-thermal-conductivity single-crystal
diamond (SCD) could enable devices with self-thermal management. The team consisted
of researchers from Kyushu University, National Institute of Advanced Industrial
Science and Technology (AIST), Kyushu Institute of Technology in Japan, and one
from Aswan University in Egypt and the Center for Japan-Egypt Cooperation in Science
and Technology (E-JUST Center) in Japan. The researchers see their work as supporting
“further research on scalable β-Ga2O3/diamond hetero-structures for future electronic
and optoelectronic applications..."
June 1931 was a year and a half into the
Great Depression, which began with the Wall Street crash of October 1929. It followed
on the heels of the very prosperous decade known as the "Roaring Twenties," when
significant, rapid advances in technology had taken place in electronics, medicine,
physics, chemistry, and other fields. A huge number of radios were sold to the military,
businesses, and private consumers both before stock market crash and after. A quick
look at my list of Radio Service Data Sheets from the era show that to be so. In
fact, it wasn't until World War II that production of new radio sets began
to decrease, as all available resources were applied to winning the war rather than
creature comforts. Back to 1931, though. Even with a severe downturn in the economy
and unemployment skyrocketing, a few industries continued to provide relatively
decent opportunities for skilled workers; electronics servicing was one of them.
Although pay levels were not as good as before the Crash, at least there was work
available to electronics technicians who were able to keep equipment functioning.
This ad is typical of many placed by
Coyne Electrical School in Radio-Craft and other trade magazines...
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!
Providing full solution service is our motto,
not just selling goods. RF & Connector Technology has persistently pursued a management
policy stressing quality assurance system and technological advancement. From your
very first contact, you will be supported by competent RF specialists; all of them
have several years of field experience in this industry allowing them to suggest
a fundamental solution and troubleshooting approach. Coaxial RF connectors, cable
assemblies, antennas, terminations, attenuators, couplers, dividers, and more. Practically,
we put priority on process inspection at each step of workflow as well as during
final inspection in order to actualize "Zero Defects."
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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