|
 Louis Garner was the semiconductor guru
for Popular Electronics magazine in the 1960s when he wrote this article
attempting to
demystify the proliferation of over 2,000 transistor types. He devised a "transistor
tree," tracing evolution from the obsolete point-contact transistor - unstable with
high gain but noisy - to advanced designs balancing cost, frequency, power, and
reliability. It covers pnp and npn basics, then details processes: grown-junction
(inexpensive, good high-frequency); meltback diffused (similar, better response);
alloyed-junction (popular for power); surface-barrier family (SB, SBDT, MA, MADT;
excellent high-frequency, low voltage); post-alloy-diffused...
 "Gentlemen,
ei*π
+ 1 = 0 is surely true, it is absolutely paradoxical; we cannot understand
it, and we don't know what it means. But we have proved it, and therefore we know
it must be truth." - Benjamin Peirce
(not to be confused with Captain Benjamin Franklin "Hawkeye" Pierce), 19th century Harvard mathematician.
ei*π
+ 1 = 0 i, BTW, is known as
Euler's identity
- engineers live by it.
 "Scientists have shown that
twisting a crystal at the nanoscale can turn it into a tiny, reversible diode,
hinting at a new era of shape-engineered electronics. Researchers at the RIKEN Center
for Emergent Matter Science, working with collaborators, have created a new technique
for building three-dimensional nanoscale devices directly from single crystals.
The approach uses a focused ion beam instrument to precisely carve materials at
extremely small scales. Using this method, the team shaped tiny helical structures
from a topological magnetic material made of cobalt, tin, and sulfur, known by its
chemical formula Co3Sn2S2..."
 I am constantly amazed when reading stories
about how easily Adolph Hitler rose to power in Germany by encouraging and exploiting
resentment of his countrymen over being forced, among other concessions outlined
in the Treaty of Versailles, to disarm militarily and make reparations for atrocities
committed in World War I. Part of the Nazi (National Socialist) party success
was extensive use of propaganda via print, radio, and the relatively new technology
of television. Government exercised complete control over the mainstream media (i.e.,
not "underground") by dictating content that promoted the proclaimed virtues of
Nazism and the Aryan race and the vices of just about every other form of government
and race. At the height of Hitler's reign of terror during the Third Reich era,
radio and television sets were only permitted to use crystals
tuned to state-sponsored...
 Manmade electrical noise (QRM) and natural
electrical noise (QRN) has been the nemesis of communications
- both wired and wireless - since the first signals were sent. While it is true
that over the last century the amount of "background" noise has increased significantly,
the ability of modern circuits to deal with (reject) it and/or accommodate (error
correction) it has pretty much kept up with the advancement. You might be tempted
to think that "back in the good old days" such problems did not exist, but operators
were plagued by poorly designed and inadequately filtered transmitters as well as
really deficient electrical service installation that spewed noise from transformers,
inadequately grounded transmission lines, lousy connections...
 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 354,801 products from more than 2478 companies
across 485 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.
 The debate about upgrading electronics service
shop equipment
from vacuum tube to solid-state instruments was raging in the late 1960s, when
this Mac's Service Shop story appeared in Electronics World magazine. Barney
is querying Mac regarding FET-based VOM performance specifications he is considering
to replace a VTVM. He covets the Hewlett-Packard 217A square-wave generator, delivering
clean 1 Hz-10 MHz waves with 5-ns rise time and scope triggering, justifying its
$300-$400 cost for precise scope testing. An electronic counter for 5 Hz-10 MHz
frequencies, with four- or six-digit readouts and line- or crystal-gated accuracy..
 A lot of people like to demean engineers
and scientists for their propensity to want to
conduct experiments and obtain measured, empirical data rather
than "winging it" and being satisfied with "intuitive" knowledge or the contemporarily
popular term "gut." If mankind had not adopted scientific methods and ventured beyond
the "cradle of civilization" on the African continent, we would all still be living
in grass huts, hurling rocks at prey, making clicking sounds for communication,
and foraging for berries. Quantifying and categorizing all things in nature helps
inventors create new and improved implements that help make life better. Early on
it was mostly individuals like Archimedes, Euler, Newton, and Edison who built the
pool of knowledge that fed and evolved into corporations, governments, and universities
doing the vast majority of the work. Bell Laboratories...
 "A new metasurface lets scientists flip
between ultra-stable light vortices, paving the way for tougher, smarter wireless
communication. Scientists have developed a new optical device capable of producing
two different types of vortex-shaped light patterns: electric and magnetic. These
unusual light structures, called
skyrmions, are known for their exceptional stability and resistance to interference.
Because they hold their shape so reliably, they are strong candidates for carrying
information in future wireless communication systems. 'Our device not only generates
more than one vortex pattern in free-space-propagating..."
 You can buy a pretty good metal detector
today for a hundred dollars that will find coins buried many inches deep and larger
metallic items even deeper, and you even get discriminator functions to filter out
unwanted objects like tin cans. They weigh just a couple pounds and can be used
with one arm. Compare that to early
metal detectors that had huge induction coils on a frame so heavy
that shoulder straps were needed just to lug them around. Some models came on wheels
for pushing or pulling like a cart. You could plan to spend a few hundred dollars
(a thousand or more in today's dollars) for one. Even then, they were not as sophisticated
as the $50 models sold in Walmart now. In classic fashion, teen electronics hobbyists
Carl and Jerry use their technical prowess to design and build their own metal detector
and then unintentionally using it to convince...
 This might be one of the earliest printed
instances of Harold A. Wheeler's simplified formulas for the
three basic inductor forms. Wheeler is credited with having devised the first
automatic volume control (AVC) using diode envelope detection. We all use them on
a regular basis, but for most the origin was never known or has long since been
forgotten (I fall into the latter category). I did some research on Wheeler's
inductance formulas a few months ago while working on what is now titled "RF Cafe
Espresso Engineering Workbook™," so it was sort of déjà vu when this blurb appeared
in a 1932 edition of Radio-Craft magazine...
 The leading website for the PCB industry.
PCB Directory is the largest directory of
Printed Circuit Board (PCB)
Manufacturers, Assembly houses, and Design Services on the Internet. We have listed
the leading printed circuit board manufacturers around the world and made them searchable
by their capabilities - Number of laminates used, Board thicknesses supported, Number
of layers supported, Types of substrates (FR-4, Rogers, flexible, rigid), Geographical
location (U.S., China), kinds of services (manufacturing, fabrication, assembly,
prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.
 Don't let the title fool you. This "Ultrafax" system developed by RCA in the late 1940s was essentially
the first attempt at video on demand, or streaming video. Rather than piping the
signal over cable or local broadcast frequency towers, a microwave link was used.
While initial system equipment space and financial requirements meant only corporations,
universities, and governments could procure an Ultrafax, engineers who developed
the system envisioned an eventual culmination of equivalent systems in every home.
Even at the end of the last century it was still not possible for program providers
to personalize broadcasts to individuals. It wasn't until broadband Internet came
on the scene in the 2000s that such services were possible. Now, a decade later,
people watch any video they want on cellphones while riding in a car...
 Maxwell's inception of the theory of electromagnetic
radiation is compared here to if Christopher Columbus had conceptualized the existence
of America and mapped its features based solely on observations of how the known
oceans and land masses interacted. I have always been amazed at the ability of people
who formulate entirely new theories of science, finance, medicine, etc., and manage
to detail and support their ideas with hard data and mathematics. Einstein did so
with relativity, Dalton did so with atomic structure, Darwin did so with evolution,
Pasteur did so with germ theory; the list is long. There are lots of geniuses out
there, but a relative few change the world...
 "A research team affiliated with UNIST has
introduced a novel, high-performance, and thermally stable polymer-based non-volatile
analog switch. This next-generation device is as
thin and flexible as vinyl, yet capable of withstanding high temperatures. Professor
Myungsoo Kim and his team from the Department of Electrical Engineering at UNIST,
in collaboration with Professor Minju Kim from Dankook University, have developed
this robust, flexible radio-frequency (RF) switch. Such technology could enable
reliable 5G and 6G wireless communication in demanding environments -- such as wearable
devices and the Internet of Things (IoT)..."
 Werbel Microwave began as a consulting firm,
specializing in RF components design, with the ability to rapidly spin low volume
prototypes. Our
WM4PD-0.5-18-S is a wideband 4-way in-line power splitter covering 500 MHz
to 18 GHz with excellent return loss, low insertion loss, and high isolation
performance. The device covers several military radios letter octave bands in one
product, delivering much value to the program. Aluminum enclosure measures 6.25
x 2.98 x 0.50", includes four through-mounting holes, and has durable, stainless
steel SMA female connectors. One device covers the upper UHF band, as well as L,
S, C, X and Ku bands...
 This week's
Wireless Engineering crossword puzzle contains the usual collection
of only 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!
 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."
 "Essayons," that's the motto of the U.S.
Army Corps of Engineers. It means "Let us try," in French. In 1968, when this
G.I. Engineers editorial appeared in Electronics World magazine, it
noted that about 38,000 engineers, or roughly roughly 6% of the nation's total,
served in the U.S. Armed Forces, far more technically skilled than in World War
II or Korea. Despite surpluses in bachelor's-degree holders, advanced-degree shortages
persisted, with over 15 thousand master's and PhD positions unfilled - by fewer
than 8,500 qualified personnel, forcing underqualified assignments. Utilization
varied: Air Force effectively deployed 14,000 engineers in R&D and civil roles;
Navy specialist programs covered ship, ordnance, aeronautical, and Civil Engineer
Corps (Seabees)...
 Here is a handy-dandy baker's dozen worth
of "kinks," otherwise known as
tricks, shortcuts, or clever ideas, that could prove useful while
working in the lab at work or in your shop at home. One suggestion is to place a
sheet of tracing paper over your schematic while wiring a circuit and draw each
connection as it is completed, rather than mark up the original drawing. That was
definitely good for a time when making a spare copy of a magazine page or assembly
instruction from a kit was not as simple a matter as it is today...
 "Apple has published a patent application
describing a method to detect user gestures on wireless earbuds by measuring changes
in RF antenna impedance, potentially reducing the need for dedicated touch-sensing
hardware. The filing, titled 'Gesture
Detection Based on Antenna Impedance Measurements,' published on January 8,
2026 as US 20260010234, describes using antennas already present for wireless communication
as dual-purpose components that can also detect user input..."
 This week's
crossword puzzle has the theme of electronics and engineering
magazines and their editors. I have to plead guilty at not knowing who the editor-in-chief
(EiC) of many of the publications were. After so often reading the names of the
many authors and technical editors and contributing editors, etc., getting printed
every month, keeping track is difficult. You should recognize all the magazine names
since they are our industry's primary publications. Apologies to Microwaves &
RF magazine (Nancy K. Friedrich, EiC), and to High Frequency Electronics
(Scott Spencer, EiC), for not including them in the puzzle. The fact is, though,
that the more words I insert at the outset, the more difficult it is...
 Exodus Advanced Communications, is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Exodus'
AMP20097 Pulse Amplifier is designed for Pulse/HIRF, EMC/EMI Mil-Std 461/464,
and radar applications. Providing superb pulse fidelity and up to 100 μsec
pulse widths to 10 kW peak power. Duty cycles to 10% with a minimum gain of
63 dB. Available monitoring parameters for forward and reflected power in watts
and dBm, VSWR, voltage, current, and temperature sensing for outstanding reliability
and ruggedness in a compact 7U chassis...
 If you have been searching for a do-it-yourself
VLF loop antenna that can be resonated from approximately 14 to
25 kHz, then look no more. This article from a 1963 edition of Electronics
World presents a relatively simple to build job that reportedly provides excellent
reception. At these frequencies a wavelength is measured in miles, which makes even
a simple dipole antenna impractical, so the multi-turn loop is the only alternative.
It is the same principle that allows the little ferrite-core antenna inside your
AM radio to work so well when the shortest wavelength in the commercial AM broadcast
band is nearly 600 feet...
 This 1968 Electronics World magazine
article nails the basics of
trade secrets law that still hold today: if you learn your boss's secret info
- like formulas, processes, or customer lists that give them a business edge - you
can't share it with a new job, even by accident, and your new employer can get sued
if they know about it and use it. No signed paper needed; courts protect "real"
secrets (not public stuff or your general skills) with court orders to stop use
or money damages. Good faith matters - act fair, don’t copy files or exact products,
and you have defenses like competing honestly. Big changes now: almost all states
follow uniform rules (UTSA) plus a 2016 federal...
 Here is a batch of
electronics-themed comics that appeared in the July 1948 edition of Radio
News magazine. The comic on page 122 would probably elicit cries of racism
or hate speech these days, even though there is nothing racist about it. Note how
prescient the comic on page 140 was. It shows how long futurists have ben contemplating
the technologies that have become or are becoming common place today - of course
many of them were promised to us by the end of the last century by the like of
Popular Mechanics, Mechanix Illustrated, et al...
|
 • Continuing
Your Professional Education in 2026
• India Reaches
400M 5G Subscribers
in 3 Years
• EIB Backs
Europe's 1st Gallium Production Investment
• 2026 a
Pivotal Year for 6G Standardization
• New
60-Meter Frequencies for Hams
• EMC
Test Lab Market Expected to Double in 10 Years
 The
RF Cafe Homepage Archive
is a comprehensive collection of every item appearing daily on this website since
2008 - and many from earlier years. Many thousands of pages of unique content have
been added since then.
 The Yagi–Uda antenna (usually referred to
as a Yagi), is a relatively simple to construct multielement structure consisting
of a combination of driven (director) and reflective (reflector) diploes. Careful
phasing of the configuration results in a directional radiation pattern that is
used often for long distance (DX) and direction finding work. It is also useful
in a dense signal environment where there is a need to exclude received signals
not emanating from a preferred source. Common (or what used to be) rooftop television
antennas were of the Yagi type and served not just to pull in distant stations,
but to help reject multipath signals that would cause ghost images on the screen.
The concept is the 1926 brainchild of Messrs. Shintaro Uda and Hidetsugu Yagi, both
of the Tohoku Imperial University, in Japan. The Yagi antenna described in this
1952 issue of Radio & Television News magazine is for VHF channels
2-13...
 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+ 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...
 RF Cafe visitor Kevin A., of Roanoke,
VA, sent me this article from the September 1972 edition of the American Radio Relay
League's QST magazine. He was motivated to send it after reading some of
the articles I posted from WWII era QSTs. We can all probably relate a
story similar to the one told here. How many "Old Al" types - the
antithesis of an "Elmer"
- are out there who knowingly or unknowingly frustrate others from participating
in an otherwise fun activity because he insists on beating up on a trivial topic
ad nauseam? You can feel the angst in the author's voice while reading. Ray, are
you out there? Is this story real or fictitious? It could easily be either...
 Yay for us. Our
pollution production levels
are way down compared to what they were in the middle of the last century. Seriously,
things were getting really bad. Pittsburgh was considered such a hopeless mess that
famed architect Frank Lloyd Wright, whose landmark Fallingwater home sat nearby,
when asked what to do about Pittsburg's terrible pollution responded, "Abandon it."
Lake Erie had been declared officially dead. Love Canal dominated headlines. Los
Angeles air was (and still is, BTW) unbreathable. After huge public awareness campaigns,
cleanup efforts, and stricter enforcement of pollution laws, the trend halted and
has reversed. That is unquestionably good news. The bad news is that as pollution
control got better, companies found continuing manufacturing operations in the U.S.
was unprofitable based on what people were willing to pay for their products. Steel,
the literal and figurative backbone of industry, could not be mined, smelted, and
processed into finished goods at a price that would encourage innovation and growth...
 This
reactance measuring bridge circuit which appeared in a 1931 issue of Radio-Craft
magazine employs a very unique element for generating an alternating current: an
electromechanical buzzer which doubles as an audio source. Sure, it doesn't produce
a pure sinewave, but for the method used here to determine inductance and capacitance
it does not matter. Rather than attempting to measure an absolute value of inductance
or capacitance, a known reactance is used as part of a balanced bridge. This is
by no means a precision instrument since accuracy depends on the user's interpretation
of the presence or absence of an audible "buzz" in a pair of headphones, but in
an era when "real" test equipment was beyond the budgets of many (maybe most) hobbyists,
the scheme was better than nothing at all...
 To the benefit of both professionals and
hobbyists, Radio News magazine published
Information Sheets each month that readers could easily cut out and insert into
a notebook as a handy reference. For example, one Information Sheet presents basic
information on the current-producing color sensitivities of common elements like
cesium, rubidium, and potassium, along with that of the human eye for comparison.
Another Information Sheet has a table of resistor values useful for constructing
a range-selectable voltmeter from a simple milliammeter. Also, just as today you
can buy a nearly complete AM or FM radio in the form of an IC (plus a handful of
external components), it was possible even in 1930 to buy a complete radio receiver
for integration into a chassis either as just a radio or as part of a combination
unit that might also contain a record player. Some spec sheets for a few of those
are included here as well just so you can see what they looked like - including
all the vacuum tubes...
 Bell Telephone Laboratories was largely
responsible for designing and building a communications system that was the envy
of the world. Innovation on the part of Bell engineers, manufacturing staff that
produced the equipment, and technicians who serviced the systems deserve the credit
as do management types who made funds and opportunity available to the aforementioned.
As the number of telephone service subscribers grew and reliability became even
more vital to business, law enforcement, and national defense, new methods had to
be devised. In the late 1950s, Bell introduced the concept of wireless microwave
links at 11 GHz (X band), which at the time X band was primarily used (at 10 GHz)
by precision approach aircraft radar. This advertisement in a 1959 issue of
Electronics World magazine promoted Bell's achievement...
 While we're on the topic of VTVMs, Popular
Electronics magazine ran a 5-part series on test equipment usage. This installment
(part 4) is on the use of a
vacuum tube voltmeter (VTVM) for making DC measurements. Don't pass over the
article just because it refers to a vacuum tube tester since there are lessons that
apply to even the most modern transistorized, computerized meter. Author Larry Klein
discusses mainly the DC functions, providing both functional descriptions of the
circuits and how to use them for making accurate measurements. FET-input digital
multimeters (DMMs) have largely replaced VTVMs, but they can still be found in some
older electronics development labs and hobby benches...
 Hmmm... this is the first time recall either
of Carl's or Jerry's father, at least where either was present in the story. Their
mothers are mentioned on occasion for providing sandwiches or uttering words of
caution when embarking on a sleuthing mission. In this episode entitled "Two Tough Customers," creator and author John T. Frye have
the techno-teens set out on an adventure to shop for a good deal on a fundamentally
sound car - which they would own in a partnership set up by their fathers. As you
would expect if you are an ardent C&J follower, their effort includes inspecting
not just the mechanical integrity but also the electrical system health. Frye always
used his stories as the basis for a lesson on some technical aspect of everyday
life. The boys broke teenage car owners into three groups: Hot-Rodders, Show-Offs,
and Mechs. They seemed to assign one trait or the other, but not a combination
thereof. Personally, I was a bit of all three with my first car - a 1969
Camaro SS. While reading, see if you notice what I did about the battery
measurement...
 Here is a sample of what passed as big news
in the electronics world in 1965 as reported in none other than Electronics
World magazine. Linear integrated circuits were beginning to be designed into
commercial products and a lot of effort and money was invested in promoting the
newfangled technology to the public. Prices were rapidly falling as acceptance increased.
The truth is the vast majority of the general public had no idea what the
difference was between vacuum tube and semiconductor equipped radios, televisions,
phonographs, tape recorders, etc., from a performance standpoint. What they did
notice was the smaller size, lack of warm-up time, and lower power consumption (i.e.,
less heat). Prices were about the same at the beginning of the technology transition.
Some anti-semiconductor naysayers tried to argue that at least with tube equipment
you had a chance of fixing a malfunctioning unit simply by replacing a $1 tube,
but failed to note that the equivalent semiconductor product almost never experienced
a failure. Of course there were some crappy transistorized products, but that was
the exception rather than the rule...
 I don't know about the rest of the country,
but this Monday morning in Erie, Pennsylvania, is cold and snowy. That means people
going to work had to shovel their driveways, maybe brush snow and ice off their
windows, and brave hazardous conditions on the streets on the way to the office.
Moods are understandably less than jovial and nerves might be shot. For those of
you who identify with this scenario, these
electronics-themed comics from a couple vintage Radio &
Television News magazines might help assuage your anxieties. The same goes
for those who are in Southern California and managed to arrive safely from a commute
on the notoriously unfriendly highways there. As with many of these old comics,
you have to be privy to the mindset of the day to fully appreciate the topic. TV
repair was big business and people were fascinated with the boob tube innovation
rapidly consuming the attention of domestic dwellers...
 Ask and ye shall receive... at least sometimes.
I posted a request for an article by science fiction writer Arthur C. Clarke, of
2001: A Space Odyssey fame, describing a
geostationary satellite system that was published in the October
1945 edition of Wireless World magazine. Thanks to RF Cafe visitor Terry
W., from the great state of Oklahoma, it is now available for everyone to enjoy.
Clarke was not just a sci-fi writer, but also an educated visionary and card-carrying
member of the British Interplanetary Society, who proposed many technological solutions
to issues of his day. In this instance, the challenge was developing an efficient
means to distribute TV signals across Europe and the world. Clarke's calculations
for the necessary number of repeater towers proved that concept impractical, so
he proposed using modified surplus German V2 rockets to launch Earth-orbiting "artificial
satellites," powered...
 The Varian brothers, Russell and Sigurd,
are widely credited for invention of the klystron around 1937. Credit for further
developments in the
klystron - from its technology to origin of the name - is a bit fuzzy based
on many articles I have seen. According to a 1944 Radio News magazine article,
Sperry Gyroscope Company developed the tube into commercial viability and was assigned
the trademark name "klystron" based on their creation of the field of "klystronics."
However, the Wikipedia entry for Stanford professor Hermann Fränkel claims the name
"klystron" was suggested by him. This full-page Bell Telephone Labs promotion in
a 1956 issue of Radio-Electronics magazine tells of their 60 GHz klystron
design by employee G.K. Farney, but makes no mention of the device's history.
Bell Labs is unquestionably responsible for untold numbers of paradigm-changing
inventions, but for some reason the omission of that information - especially so
close in time to the klystron's arrival on the commercial scene - bothers me a bit...
 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 225,000 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...
 This custom
Ham Radio themed Crossword Puzzle for July 17th, 2022, is brought to you by
RF Cafe. All RF Cafe crossword puzzles are custom made by me, Kirt Blattenberger,
and have only 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!
 I was first introduced to the concept of
receiver noise figure at the start of my engineering career in
1989 at General Electric AESD in Utica, NY. During my four years in the U.S. Air
Force working on airport surveillance and precision approach radars, I do not recall
having ever heard the term noise figure or noise temperature. We did signal to noise
and signal sensitivity measurements as part of the normal maintenance, but the terms
never arose. Ditto for my courses at the UVM. We never did cascade parameter calculations
for noise figure, intercept points, compression points, etc. That is primarily the
realm of practicing...
 The National Science Foundation's 1000-meter
Arecibo radio telescope, carved into a Puerto Rico mountain valley, was commissioned
on November 1, 1963. Justification in funding the colossal project was partly from
the Department of Defense because of a need to characterize the Earth's upper atmosphere.
Satellites and looming threats of soon to be developed ICBM traffic were of prime
concern. One of the renowned uses of the Arecibo radiotelescope was when Carl Sagan's
team transmitted a "we are here" message toward the M13 globular cluster in the
constellation of Hercules in 1974. The amount of research and data collected over
the ensuing six decades has been invaluable from both communications and astronomical
perspectives. Tragically, on November 7, 2020, the dish suffered a catastrophic
mechanical failure in the suspension supports, resulting in irreparable damage.
Planning on the site's future is ongoing...
 Mac and Barney discuss with some degree of trepidation
the alarmingly increasing rate at which new
electronics technology is being developed and marketed. As service shop owner and
technician, respectively, they needed to constantly educate themselves on new components
and circuits in order to stay current and be efficient enough to turn a profit. Mac recounts
his lengthy background beginning with the days of mainly battery-powered AM radios, and
progressing through AC-DC, FM and all-band (shortwave) radio, B&W television and
the color TV, CB radios, and a new breed of appliances with electronic controls... |
