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 "The standards governing chiplet technology
now have a second iteration. The
Universal Chiplet Interconnect
Express (UCIe) Consortium, which was formed in March 2022, recently released
its 2.0 specification with updates that address design challenges for testability,
manageability and debug (DFx) for the SiP lifecycle across multiple chiplets. A
key feature of the update is support for 3D packaging to enable chiplets to dramatically
increase bandwidth density and power efficiency. In a briefing with EE Times, consortium
chair Debendra Das Sharma said that the UCIe 2.0 specification is fully backward
compatible, while introducing optional manageability features..."
 Westinghouse Electric Corporation, one of
the most influential companies in the development of American industry, innovation,
and technology, was founded in 1886 by George Westinghouse (1846-1914). Westinghouse
was an inventor and industrialist who held over 300 patents and had already revolutionized
the railway industry with his invention of the air brake system. He sought to apply
his inventive genius and business acumen to the burgeoning electrical industry,
and his new company would soon become a powerhouse in electrical engineering, energy
production, and consumer electronics. George Westinghouse was a visionary who saw
electricity...
 The newest release of RF Cafe's spreadsheet
(Excel) based engineering and science calculator is now available -
Espresso
Engineering Workbook™. Among other additions, it now has a Butterworth Bandpass
Calculator, and a Highpass Filter Calculator that does not just gain, but also
phase and group delay! Since 2002, the
original Calculator Workbook has been available as a free download. Continuing
the tradition, RF Cafe Espresso Engineering Workbook™ is also
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...
 Thanks to this 1959 installment of "Mac's
Service Shop," which appeared in Radio & TV News magazine, we now know
who was responsible for the ozone hole discovered in the 1970s: It was the electronics
service industry. Thanks to products like General Cement's "Spray-Koat
Circuit-Cooler," which was pure canned carbon dioxide, ecocriminal technicians
in workshops and living rooms across the country - and across the world - indiscriminately
loosed life-threatening volumes of the gaseous poison into the atmosphere whilst
troubleshooting radios, TVs, stereo systems, tape...
 Exodus Advanced Communications, is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. We are pleased to announce
the Exodus Advanced Communications
AMP2025A solid state high power amplifier, which operates from 800 to 2500 MHz
at greater than 300 W. The unit produces >400 W nominal power with >150 W
P1dB. Designed for EMI/RFI, lab, CW/pulse and all communication applications, the
AMP2025A's minimum gain is 55 dB with excellent flatness. Included are amplifier
monitoring parameters for Forward/Reflected power, VSWR, as well as voltage, current &
temperature sensing for optimum reliability & ruggedness...
 Even in this era of incredibly complex electronics,
nearly every communications circuit, whether analog, digital, or a mix thereof has
a
crystal oscillator somewhere at its heart - sometimes even within an integrated
circuit. Technology has advanced significantly in the design and manufacture of
crystals, but fundamentally the key parameters of center frequency, phase noise,
stability over temperature and time (aging), susceptibility to microphonics effects
and magnetic fields, etc., are the same. This 1964 Electronics World magazine
article is a good primer on crystals that explains how they work and how they are
used...
 "The U.S. Space Force has awarded its
Deep-Space Advanced Radar Capability (DARC) Site 2 contract. This is for a location
in the UK as part of its role as an AUKUS partner. DARC will track objects in the
geosynchronous orbit GEO with the aim of protecting critical satellites. A global
network of three advanced ground-based sensors, it will be operated in collaboration
with AUKUS alliance partners: the United States, Australia and the United Kingdom.
The next generation ground system will also be supporting warfighters of the U.S.
and its allies. It is anticipated that Cawdor Barracks (formerly RAF Brawdy) in
Pembrokeshire will be the location for the UK site..."
 Electron current flow (as opposed to conventional
current flow), the movement of electrons from negative to positive, is a fundamental
concept in the study of electricity and electronics. This phenomenon arises due
to the behavior of electrons, the negatively charged particles that are an essential
component of atoms. To fully understand electron current flow, it is important to
grasp both the historical context and the physical principles that define how and
why electrons move the way they do. In the early history of electrical theory, long
before the discovery of the electron, scientists assumed that electric current flowed
from a higher potential (which they called the positive terminal) to a lower potential
(the negative terminal)...
 With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils available
for RF, analog, and digital system and schematic drawings! Every stencil symbol
has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks, and
more. Page templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols...
 The old adage about history repeating itself
is borne out once again in this "News
Briefs" feature in a 1961 issue of Radio-Electronics magazine. When
cellphones, Wi-Fi and Bluetooth enabled portable computers came about, commercial
airlines prohibited turning them on while in flight due to concerns that unintentional
radiation emanating from the devices might interfere with navigation and communications
systems, thereby posing a safety threat. In 1961, the FCC imposed a ban on in-flight
FM radio usage. In other news, CBS announced it was phasing out production of vacuum
tubes, as transistors were dominating the industry. At the same time, Amperex boasted
of a new type cathode which could heat to operating temperature in a tenth of a
second (old guys like me remember waiting for the radio and TV to heat up before
becoming functional). Anyone else...
 An
iconoscope was an early
form of television image capturing tube. Some amateur radio operators were experimenting
with slow scan TV even back when the technology was relatively new to the world.
When this article was written in 1944, there were still large portions of the United
States that did not have television broadcast coverage. Of course I would argue
that at the time of my growing up in the 1960s and early 1970s a lot of areas -
even suburbs - were still not covered by TV signals, based on how cruddy the reception
at my parents' house was. But I digress. The article mentions that because of the
lack of TV coverage...
 "The
global supply chain is currently facing a perfect storm. A confluence of challenges,
including a surge in late payments, a persistent labor crunch, and relentless inflationary
pressures, is creating unprecedented problems in the flow of goods and services
worldwide. From soaring raw material costs to labor shortages in crucial sectors,
these interconnected issues are far-reaching, affecting businesses, consumers, and
the global economy. Recent data from Taulia, a financial technology company, paints
a worrying picture of late payments in global supply chains. The proportion of suppliers
affected by late payments has surged..."
 Amperex Corporation, originally a division
of Philips Electronics, was an influential American manufacturer of electron tubes
and semiconductors, renowned for its innovations in vacuum tubes that powered early
communications, radar systems, and broadcast devices. Established in the early 20th
century, Amperex played a crucial role in the advancement of electronics during
the vacuum tube era and the transition to semiconductor technology. The company's
legacy endures, especially among audiophiles and vintage electronics enthusiasts,
due to the high quality of its products. The origins of Amperex trace back to 1922,
when Michael Pawlowski, a Russian immigrant and expert in vacuum tubes, founded
the company in New York. Amperex was a portmanteau of "American" and "experimental,"
reflecting its commitment to research...
 For those of us who like to wax nostalgic
over our early days of building electronics kits, here is a two-page spread from
Heathkit in a 1969 issue of Electronics World magazine. That year was
pretty much at the beginning of my more serious involvement in electronics, which
had spawned a few years earlier but was really kick-started after getting a "Radio
Experimenter" kit for Christmas. It had parts for an AM radio with a breadboard
that used springs as attachment points for the components. Being "so easy a caveman
could do it" (per a certain set of insurance company commercials), I actually was
able to hear a broadcast through the ear bud from the local AM radio station (WNAV
in Annapolis, Maryland). It would be a couple more years - probably because I had
not heard...
 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 average0,000 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...
 Robert P. Balin created many great
quizzes for Popular Electronics magazine in the 1960s and 1970s (see list
below). This is only the second quiz by Mr. Balin I have seen in Radio-Electronics
magazine (see Sawtooth Sticklers). "Can
You Name These Strange Electronic Effects?" is one of the more difficult quizzes,
because it requires you to know the names of the effects - no list of potential
answers to match with are given. Being an old guy and having posted articles referencing
many of these effects, I was able to eke out a score of 80%. For item #4, I took
a WAG at the answer and got it right, probably because of so many articles about
Lee de Forest's invention of the Audio vacuum tube amplifier. Don't let that
clue fool you though...
 "Scottish inventor
John Logie Baird had a lot of ingenious
ideas, not all of which caught on. His phonovision was an early attempt at video
recording, with the signals preserved on phonograph records. His noctovision used
infrared light to see objects in the dark, which some experts claim was a precursor
to radar. But Baird earned his spot in history with the televisor. On 26 January
1926, select members of the Royal Institution gathered at Baird's lab in London's
Soho neighborhood to witness the broadcast of a small but clearly defined image
of a ventriloquist dummy's face, sent from the televisor's electromechanical transmitter
to its receiver..."
 EIRP -
effective isotropic radiated power - is an important parameter when calculating
both intentional and unintentional electromagnetic emissions. EIRP is a vector quantity
that accounts for both power (magnitude) and 3-dimensional coordinates (direction).
It includes antenna directivity that concentrates power in a particular direction
rather than distributing it equally in all directions (e.g., isotropically). Effective
radiated power factors in modulation type and power envelope shape as well. Knowing
how to measure those quantities can make the difference between passing and failing
FCC (or other countries' spectrum regulating bodies) certification. This 1973 issue
of Popular Electronics magazine provides a good introduction to EIRP...
 "It's the start of the new college year
and we want to help you kick it off in style. Enter [DigiKey's]
Back to School
Giveaway for a chance to win up to $1,000 of DigiKey store credit. That's $1,000
worth of any products currently available on digikey.com. Elevate your projects
to another level, or just keep the parts for your next great idea. Either way, we
understand. We get technical. If you are working on an engineering Senior Design
project or Capstone project, here is your big break." No previous accomplishments
necessary - just a pulse.
 If you were to think the effort to
encourage women to join the ranks of engineers is a recent thing, you'd be wrong.
Contrary to what news media rabble-rousers want you to believe, women have long
been welcome in the engineering world. Some, admittedly, were initially as welcomed
by men into engineering as men were by women into nursing, but those who persisted
usually excelled. As hard as it is for social engineers to accept, evidently most
women, at least at this point in history, would rather pursue career fields other
than engineering. I have posted stories like this one from a 1963 edition of
Electronics World that beseech girls and women to pursue all the fields of
science - not just engineering. See "Making Wartime Engineers" and the "National
Union Radio Corporation" ad in a 1945 issue of Radio Craft...
 Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products such as
RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters.
Since the conception of WFT, we have introduced products that have been purchased
by a wide range of customers, from hobbyists to education facilities to government
agencies. Worldwide customers include Europe, Australia, and Asia. Please contact
Windfreak today to learn how they might help you with your current project.
 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...
|
 This is the electronics market prediction for
West Germany, circa 1966. It was part of a comprehensive assessment by the editors
of Electronics magazine of the state of commercial, military, and consumer electronics
at the end of 1965. West Germany was intent on being a player in the Space Race with
Siemens and Telefunken providing expertise. Bochumer Verein was pushing the
electronic computer frontiers forward. The article states that only about 5% of
West Germany's factories including heavy industry have anything approaching the
automation of American industry. Factory automation was viewed as a threat to
the German workers. Unless you can find a news story on the state of the
industry, detailed reports must be purchased from research companies...
 Although I do not recall seeing a lot (none,
actually) of antennas constructed in the style of this
Holloway Electronics "Expo" model, I did a quick Web search to try finding contemporary
products exploiting the concept. The "Expo" uses a set of exponentially curved elements
to maintain a more constant separation distance between individual components in
an effort to provide better gain across the entire VHF / UHF television broadcast
bands. It seems like a really good idea on paper (no computers back in the day),
but evidently in practice using an exponent of "1" (i.e., linear like all the rest)
is good enough for acceptable reception. Any noticeable performance increase over
standard antennas...
 I ran across a really nice e-book entitled
"Wireless Networking in the Developing World," which is a collaborative work by
many authors, and it is published under the Creative Commons licensing scheme (a
la Wikipedia). That permits reprinting with attribution. Some of the more pertinent
sections will be posted here on RF Cafe. "The exact theory of Fresnel zones is quite
complicated. However, the concept is quite easy to understand: we know from the
Huygens principle that at each point of a wavefront new circular waves start, we
know that microwave beams widen as they leave the antenna, we know that waves of
one frequency can interfere with each other. Fresnel zone theory simply looks at
a line from A to B, and then at the space around that line that contributes to what
is arriving at point B. Some waves travel directly..."
 According to Wikipedia, The Navy's USS Compass
Island was one of two ships, the other being USS Observation Island, converted and classified
as navigational research test vessels under the Polaris Missile system budget. As reported
here, the newfangled
radio sextant tracks the position of the sun or moon to provide location accuracy
much better than the best traditional compass. Remember that in 1959 there was no satellite
navigation, and in the middle of the ocean land-based transmitters were useless as radio
bearing references. Inertial navigation systems could not hold their calibrations in
the harsh physical environment of stormy seas. This radio sextant system is fine as long
as the sun and/or moon is high enough in the sky to have antenna pointing access to one
or...
 Decisions, decisions, decisions. As the title
states,
color television manufacturers were, in 1965, finding themselves
between a rock and a hard place, as the saying goes, regarding a change from vacuum
tubes to transistors. The buying public (aka consumers) had mixed emotions about
the newfangled semiconductors based at least partly on bad information about transistors.
Transistors had been designed in various circuits for a decade and a half and were
gaining rapidly in performance and reliability. The price was coming down, but as
reported here, still cost $5 to $10 apiece compared to a $1 vacuum tube. Company
management needed to decide whether to delay implementing the new engineering and
production methods required to deal with transistors for a couple more years until
the market had more time to make up its mind whether to begin. A couple firms enthusiastically...
 Beginning in 2000, I have created hundreds
of 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 start like Hedy Lamarr or a geographical
location like Tunguska, Russia, for reasons which, if you don't already know, might
surprise you...
 Just as with modern day wireless and cellular
network build-outs, the phenomenal costs involved in planning, implementing, maintaining,
upgrading, and expanding coverage for wired networks of yore (as well as what remains
of today's) was/is paid for by paying subscribers. Per this 1948 Radio News
magazine article, American Telephone and Telegraph (AT&T) company's investment
in network service at the time was well over $20,000,000, and that nearly a dozen
basic networks regularly used 90,000 miles of wire. The included photo of the stripped
end of a lead-sheathed multi-conductor cable is an indication of how complex and
massive the effort was. A lot of engineering hours went into developing just the
cables, let alone the citing and building of support towers, burial paths, relay
and switching stations (and getting AC power to them), lightning protection, personnel
and equipment access, and so much more. Aside from the lawsuits and court rulings
regarding monopolistic and anticompetitive practices...
 Here are a few more
electronics conundrums with which to exercise the old noodle. These are puzzlers
from a 1959 issue of Popular Electronics magazine, but at least one of
them (#4) will likely prove to be a real stickler unless you have seen a similar
resistor mesh problem before (see my solution for the resistor cube equivalent resistance).
There are no tube circuits to use as an excuse for not attempting them - just resistors,
batteries, switches, meters, a motor, and a couple light bulbs. All four would be
fair game to present to an interviewee to see where he/she stands on basic circuit
analysis...
 Have you heard about this? I hadn't. If you
think the only goal in Afghanistan is to stamp out the Taliban, think again. An
article in the October 2011 issue of Scientific American details the extensive
mineral surveys that have been carried out there in the last year or so. Afghanistan
is home to what may be the largest cache of
rare earth elements
in the world, with a potential to replace China as the largest extractor (~90%)
of those atoms that lie in the lanthanide and actinide regions of the periodic table
- the two rows that are typically pulled out of the chart. China, you may have heard,
is severely restricting the export of rare earths - wanting to keep it for themselves
- thereby triggering a near panic. Prices are rising so alarmingly that reopening
mines in the U.S. has once again become profitable in spite of the crippling regulations
that years ago closed down operations here (huge loss of jobs and tax revenue) and
forced us to become reliant on offshore supplies...
 Here are a few examples of what was considered
cutting-edge technology humor back in 1949. These three
tech-themed comics appeared in Radio-Electronics magazine. The first
one won't mean much to anyone who has never watched a television with a cathode
ray tube (CRT), but only on an LED or LCD screen. The next comic is a bit corny
and plays off the confusion some people had with the name assigned (actually the
spelling thereof) to the lower audio frequencies. The last is a pun on the extreme
measures sometimes needed to pull in a TV broadcast station before the days of cable
and satellite service.
 It seems Amateur radio operators in every
country have perpetually been in a battle against government bureaucrats. Early
on, Hams were allocated small segments of available "usable" spectrum and a fairly
wide swath of the less desirable spectrum. That was especially true of the microwave
bands when there was not a lot of components and equipment available that could
operate at the higher frequencies. Those familiar with history are familiar with
the situation where Amateurs developed a lot of the technology for operating in
the upper MHz and into the GHz realm, and then the government snatched it from them
for commercial and military use. Hams pretty much pioneered
atmospheric scatter as a means for long distance (DX), over-the-horizon communications
using those upper frequencies. This editorial from a 1955 issue of Radio & Television
News magazine reports on a relatively newer variation dubbed "forward-scatter,"
which works in 40-80 MHz band (6-meters and VHF) when the transmitted power
is sufficiently high. The military, which discovered the phenomenon and had recently
declassified it, was considering allowing Amateurs...
 Robert Taylor claims - without contention
from what I can find - to have invented the concept of "super-modulation,"
whereby the normal "splatter" created by greater than 100% amplitude modulation
(AM) can be mitigated through use of specialized circuits. As with many paradigm-changing
discoveries, much was made of super-modulation in the late 1940s through early 1950s,
and then it pretty much dropped off the charts. The cause might have been that the
sophistication of circuitry needed to keep everything tuned and tracking properly
to prevent harmonic and sideband was deemed not worth the trouble once frequency
modulation (FM) came on the scene. FM quickly gained in popularity due to its relatively
high noise immunity; in fact, many commercial radio broadcast market prognosticators
declared AM to be on life support by the end of the 1950s, with total death to come
shortly thereafter. Mr. Taylor describes in great detail the concept and circuitry
behind his super-modulation system in a two-part series of articles in 1948 issues
of Radio & Television News magazine. You'll need to put your thinking
cap on when reading these.
 This "Recent Developments in Electronics"
from a 1960 issue of Electronics World had a lot of
antenna news that included a retarded surface wave antenna with high gain and
low silhouette for use in airborne early warning radar as well as ground based and
shipboard radar, a pair of 60-foot tropospheric scatter antennas that are specially
mounted at opposite ends of a 180-mile long section of the Gulf of Mexico, and a
104-foot-long rotating 50-ton radar antenna used for the SAGE early warning system.
Also reported was Westinghouse Electric's airborne Stratovision for broadcasting
educational television programming to rural areas out of reach of existing
towers...
 The
International Geophysical Year (IGY) ran from July 1957 through December 1958
and was designed to promote cooperation between countries in the earth sciences
realm of research. In all, 67 countries participated in various IGY projects. China
declined involvement based on objections to Taiwan being involved, arguably perpetuating
its people's languishing behind the Iron Curtain of Communism much longer than it
otherwise would have. Global studies were carried out for the aurora and airglow,
cosmic rays, geomagnetism, gravity, the ionosphere, longitude and latitude determinations,
meteorology, oceanography, seismology, and solar activity. It was during this period
that the USSR launched Sputnik and the Van Allen radiation belts were discovered.
This article reports on the radio-communications-related IGY...
 Burying any antenna in the ground seems like
a bad idea from radiated field pattern and efficiency perspectives. As determined
in a 1974 paper published by the National Bureau of Standards, most of the energy
from a buried dipole antenna that is not absorbed by the ground is radiated nearly
straight up (many studies of underground antennas can be found). Motivating the
NBS's burial study was a desire to conceal radio communications antennas in covert
operations. This short piece in a 1935 edition of Short Wave Craft reports
on a case Hams were experimenting with
buried antennas in order to avoid the expense and trouble of an overhead installation.
These days, Hams want to bury antennas for those same reasons AND to get around
restrictive neighborhood and town restrictions prohibiting certain antenna installations ...
 Even in this time of readily available computers
(including your smartphone) and printers, having a set of
rubber stamps for common electronics symbols would be pretty handy; there are
some Neanderthals among us who still use pencil and paper on occasion. Simpler symbols
like resistors and capacitors are easy enough to sketch by hand, but something like
a dual gate MOSFET with diode protection can take some time to produce legibly.
Common connector types like the DB signal/power series and some RF kinds (BNC, SMA,
etc.) would be useful, as would a set of oft-used logic gates for the digital designers.
The set shown here in a 1953 edition of Radio-Electronics magazine includes a handful
of vacuum tube types which would have taken some time to draw by hand, and a few
other symbols...
 If I told you that Lester William Polsfuss
is widely credited with being a major player in the pioneering of electric guitars
due to his solid-body (no acoustic resonance chamber) designs, you might wonder
where I came up with that claim. However, if you know that Mr. Polsfuss is the surname
of Les Paul, then you would quickly agree. As if being a popular musician and, along
with wife Mary Ford, selling millions of records wasn't enough, Les Paul was also
an experimenter and inventor in the electronic music realm. This article entitled
"Les
Paul: Technician and Musician" appeared in a 1958 article in Radio-Electronics
magazine, and was at the time a contemporary look inside his home-workshop-studio,
when he was first gaining popularity...
 With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils
available for RF, analog, and digital system and schematic drawings! Every stencil
symbol has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks, and
more. Page templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols...
 Good, clean humor has always been a welcome
addition to my day whether it comes in the form of a printed comic strip, a TV show,
or someone's mouth. My father's side of the family was populated with many jokesters
who could be counted on to deliver an ad hoc pun or zinger at the appropriate moment.
The environment instilled a great appreciation for such entertainment, so these
electronics-themed comics that appeared in editions of Radio-Electronics,
Popular Electronics, et al, are a refreshing distraction from the workaday
world. An old saying claims "laughter is the best medicine," and while it cannot
cure cancer, a good dose of humor often helps ease the pain...
 The problem of and concern about our country's
youngsters seemingly not being overly interested in
pursuing technical career paths is a theme often heard in the tech news
media and workplaces. As our world grows increasingly automated and everything
from light bulbs to telephones and automobiles are so packed with "no user
serviceable parts inside," there seems to be little motivation for an otherwise
potential budding tinkerer to take stuff apart to discover what makes it work.
In the "old days" like, say, 1955, products were much more accessible to kids'
curious nature and explains why fostering the next crop of engineers,
scientists, and technicians took care of itself. You might think so, but alas,
the dilemma evidently persists with each succeeding generation...
 "After Class" is a long-running feature of Popular Electronics
magazine that covered a very wide range of topics. In most instances a single major
theme is presented, but in this May 1955 issue there are five separate areas: the
Faraday shield, binary notation, using a tuning fork to resonate a tank circuit,
and two quizzes (one on resistance and capacitance and another on power supplies).
On the topic of Faraday shields, I have to tell you about an e-mail I recently received
from an RF Cafe visitor. He wrote asking whether there was any atmospheric pressure
at which satellite radar could not penetrate to the Earth's surface. I could be
wrong, but usually questions like that are asked by people who believe in a government
conspiracy to surviel (and ultimately control) the populace. I used to dismiss such
notes as being from lunatics, but with all the cameras everywhere and the ability
to track movement via cell towers and Wi-Fi hot spots ...
 Passive repeater antennas have been used
for a long time to overcome line-of-sight-limitations of many - if not most - of
the radio communications universe. Properly designed and implemented
passive repeaters can exhibit very high levels of efficiency,
and in some cases can actually provide gain by focusing signals impinging on a large
panel of multiple wavelength dimensions onto a smaller transmitter or receiver antenna.
That is known as aperture gain. Optical telescopes are a good analogy where for
the same level of magnification at a given wavelength, a larger aperture (refractive
lens or reflector mirror) results in a brighter image at your retina or CCD...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils
available for RF, analog, and digital system and schematic drawings! Every stencil
symbol has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks, and
more. Page templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols... |
