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 The December 1969 issue of
Radio-Electronics magazine's "New & Timely" column reported that at the
National Electronic Association conference,
technicians reported burns and eye damage caused by X-radiation from color TV
sets under repair. Night vision scopes for commercial use were introduced by
Raytheon, suitable for law enforcement, industrial security, and nature study. A
joint U.S.-Indian plan planned to beam TV directly to millions of Indian
villagers via a stationary applications satellite in 1972. The French Atomic
Energy Commission used a superpowerful laser to create minute thermonuclear
explosions, fusing deuterium...
 Anatech Electronics offers the
industry's largest portfolio of high-performance standard and customized
RF and microwave filters and filter-related products for military,
commercial, aerospace and defense, and industrial applications up to
40 GHz. Three new filter models have been added to the product line in April,
including a 5500 MHz WiFi cavity bandpass filter, a 3437-3537 MHz ceramic
duplexer filter, and a 1425 MHz cavity bandpass filter. Custom RF power filter
and directional couplers designs can be designed and produced with required
connector types when a standard cannot be found, or the requirements are such
that a custom approach is necessary...
 This article published in a 1955 issue of
Popular Electronics magazine is a really good primer on the history and
working principles of the
electron microscope. It also explains why such a device is needed;
i.e., why an optical microscope cannot do the job when really high levels of magnification
are required. As object dimensions are spaced at distances near to or less than
the optical wavelength being observed, it becomes impossible to resolve into separate
features. Accordingly, when observing at the upper end of the visible light spectrum
at around 400 nm, under ideal conditions you would not be able to clearly discern
two feature less than about 800 nm apart. Current (2019) CMOS gate thicknesses
run about 5 μm, so visible light cannot be used to image those structures.
Another resolution limiting factor is aperture size, which, depending on the wavelength
causes diffraction patterns of two objects to overlap...
 If you are a seasoned vintage electronics
equipment aficionado, restorer, hobbyist, etc., then you most likely already have
your own list of supply sources for vacuum tubes. Contrary to what others might
think, there is still a healthy stock of tubes available from private websites like
Pacific T.V. (hat tip to Bob Davis), as well
as collective sites like eBay, Facebook Marketplace, Craigslist, and vintage electronic
equipment forums. Prices for common tubes are surprisingly low if you shop around.
If you need an output power amplifier for a commercial radio station, be prepared
to shell out major wampum, though. Many NOS (new old stock) varieties in original
boxes can be had, as well as used tubes. Most have been tested for specification
compliance.
 Westinghouse is yet another bulwark company
of America's foundational industrial age, beginning in the late 19th Century. George
Westinghouse founded eponymously-named company,
Westinghouse Electric & Manufacturing Company, in 1886, during the time
he was working with Nikola Tesla (I wonder whether any of the current-day anti-Tesla
nimrods are stupid enough to vandalize NT statues and monuments?) to institute a
commercial electrification infrastructure. Mr. Westinghouse began his life
of fame and fortune with a locomotive air brake design. During World War II,
Westinghouse's many locations designed and manufactured many types of products to
facilitate troops in all Theaters of Operation. This 1943 issue of Popular Mechanics
magazine carried a full-page...
 This set of three circuit analysis challenges
appeared in the January 1963 issue of Radio-Electronics magazine. Readers,
staff, and even come companies submitted the "What's
Your EQ?" (EQ = Electronics Quotient) content. As an example of the latter,
Cleveland Institute of Electronics provided "Draw the Waveform." Don't let the diode
vacuum tube deter you from the puzzle. Just mentally replace the tube with a solid
state diode symbol with the anode at the top where the tube's plate (anode) is shown.
The negative element of a tube is called the cathode, same as the solid state diode.
"Capacitor Charge" is easy enough. "Another 2-Box Light"...
 "Despite increasingly intense competition
for skills across all sectors of industry and a growing appetite amongst engineers
for a new challenge, engineering salaries appear to have stagnated over the past
12 months. This is just one of the key findings of The Engineer's tenth
annual salary survey, which is published in full on The Engineer's website
in a new interactive digital format. Attracting responses from 621 engineers working
across 12 different sectors, this year's survey was carried out between December
2024 and January 2025. As ever, the results provide a fascinating insight into
UK engineering salaries and how engineers are feeling about their careers..."
 In this 1963 issue of Radio-Electronics
magazine, editor Hugo Gernsback reflects on the early days of television, noting
that the first regular daily TV broadcast began on August 13, 1928, over radio stations
WRNY and W2XAL, which were associated with his former publication, Radio News.
Initially, these
broadcasts were silent, featuring only moving images the size of a postage stamp,
and it wasn't until 1931 that TV broadcasts included sound. Gernsback critiques
the slow progress in improving the audio quality of television receivers, pointing
out that despite advancements in high-fidelity and stereo audio technology, most
TV sets still lacked these features due to regulatory restrictions by the FCC. He
expresses hope that recent petitions to the FCC...
 Exodus Advanced Communications, is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Exodus' model
AMP20081 high power solid state power amplifier (SSHPA) is ideal for broadband
EMI-Lab, communications, and EW applications. Class A/AB linear design accommodates
all modulations & industry standards. It covers 80-1000 MHz, producing
600 W nominal, with a 500 W P1dB and 56 dB minimum gain. Excellent
flatness, optional monitoring parameters for forward/reflected power, VSWR, voltage,
current & temperature sensing for superb reliability and ruggedness...
 In that these
comics from Radio-Craft magazine have an electronics
theme, you can claim looking at them is work-related. The themes of the comics reflect
common scenarios of the 1944-1945 era in which they were published, but with not
much modification can be applied to today's environment. People will always expect
more features from products, will be critical of everything presented to them, and
will want to haggle for the best deal from the used camel salesman. You might consider
using one of them for your next conference or project status presentation. There
is a list of many more similar comics at the bottom...
 In a groundbreaking announcement that will
forever transform global communications, QentComm®©™ (Quantum Entanglement Communications)
has unveiled the world's first
commercially viable quantum entanglement communication system. Dubbed QeG®©™
(Quantum entanglement Generation, pronounced kwee-gee), supplementing the traditional
4G, 5G, and 6G nomenclature, this revolutionary technology eliminates the limitations
of traditional radio-based systems, delivering instantaneous, unlimited connectivity
across any distance without reliance on satellites, cell towers, or fiber optics.
Under the leadership of Kirt Blattenberger, QentComm (pronounced kwent-kahm) has
created a system that defies conventional physics by utilizing quantum entanglement
for real-time, secure communication between devices anywhere in the universe - including
here on Earth...
 In this "Carl & Jerry" technodrama from
a 1957 issue of Popular Electronics magazine, the two boys start out enjoy a casual
day of kite flying, using a homebrew radio-controlled camera attached to the kite
to capture an aerial view of Round Island in a lake. After successfully taking a
picture, they develop the film and discover two men and an odd setup on the island.
Curious, they return the next day, find a hidden tunnel, and stumble upon an illegal
liquor still. As you might expect, the teens run into a heap of trouble when the
moonshiners nab them. Using their combined ingenuity and knowledge of communications
methods common to Ham radio operators of the era, contact was made and help was
on the way. Read about Carl and Jerry's exploit and exactly what it was that saved
the day - and their hides!
 "In late January 2025, 17 students and staff
members from Las Animas High School (LAHS) in Colorado visited the
Deep Space Exploration Society Radio Telescope (DSES) located at the Plishner
Radio Astronomy and Space Sciences Center near Haswell, Colorado. They also got
an introduction to amateur radio. 'This first field trip visit of high school students
reflected the dreams of Michael Lowe, former DSES board president, who sought to
create a center for radio astronomy and space science education in southeast Colorado,'
said DSES President Myron Babcock, KL7YY..."
 Making format changes to magazines after
many years of an established standard always ruffles the figurative feathers of
a significant portion of regular readers. Two magazines I read monthly, Model
Aviation and QST, recently underwent a format change - both of which
I considered very nice. However, reader comments in the aftermath showed a few who
were not impressed. Popular Electronics magazine in 1966 made announcements
regarding plans to adopt some of the
newer base units for physical measurements, including this one for beginning
to use "Hertz" (Hz), along various numerical prefix forms, instead of "cycles per
second" (cps). The editors give sound reason...
 The
Beverage Antenna, very familiar to amateur radio operators, is
a simple but efficient, highly directional, non-resonant antenna that consists of
a single straight wire of one or more wavelengths that is suspended above the ground.
It is orientated parallel to the direction of intended reception. One end is terminated
to ground through a resistor, and the other is connected to the receiver. The following
quote comes from the patent (US1,81,089) text: "In accordance with theoretical considerations,
if an antenna were to be freely suspended and if the surface of the earth constituted
a perfectly conducting parallel plane, current waves would travel through...
 This letter was sent to Hugo Gernsback,
publisher of Radio-Electronics magazine, in response to the "30-Day
Record Response" article penned by noted scientist and inventor Mohammed Ulysses
Fips. In it, Stephen A. Kallis, Jr. heaped laud upon the "Most Revered and Esteemed
Fips" for his long-term recording device (remember, 1961 was many decades before
microminiature terabyte memory and microprocessors) were available, and chastises
Mr. Gernsback for evidently calling into question the authenticity of the recorder.
Kallis, a self-proclaimed stereo enthusiast, bolsters Fips' case by citing "A Proposed
Listening Area," by the Institute of Synergistic Statics Proceedings...
 Raise your hand if you're old enough to
remember doing printed circuit board layout using
Rubylith tape. My hand is up. Back in the early 1980s, I did prototype
PCB designs in an engineering development lab at Westinghouse Electric's Oceanic
Division. Most of it was for analog and RF substrates that would be photographically
reduced in size for use with bare integrated circuit die and surface mount passive
components (Rs, Ls, and Cs), upon which I would later epoxy-mount those components
and wire-bond everything using 1-mil gold wire. However, there were projects where
full-size leaded components were used on a through-hole PCB that used not only the
Rubylith tapes but also sheets with special electronics shapes for solder pads around
the holes for components leads, ground and power planes, board-edge connectors...
 "Quantum systems don't just transition between
phases - they do so in ways that defy classical intuition. A new experiment has
directly observed these
dissipative phase transitions (DPTs), revealing how quantum states shift under
carefully controlled conditions. This breakthrough could unlock powerful new techniques
for stabilizing quantum computers and sensors, making them more resilient and precise
than ever before. A new frontier phase transitions, like water freezing into ice,
are a familiar part of everyday life. In quantum systems, however, these transitions
can be far more extreme, governed by principles like Heisenberg's uncertainty..."
 In
this November 1940 issue of the Boy Scouts Boys' Life magazine, amateur
radio operators, or "hams," are described as having the ability to communicate across
vast distances, connecting far-flung locations such as Goulds, Florida, Cali, Colombia,
Cairo, Kenilworth, England, Bombay, and Brisbane. These operators, licensed by the
Federal Communications Commission, engage in various activities such as talking
to distant stations, participating in contests, and providing emergency communication
during natural disasters. With call letters assigned by international treaty, these
stations use a combination of code and phone to make contact, exchanging reports
and QSL cards. The
Radio merit badge was first offered in 1918 and has been...
 ConductRF is continually innovating and
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TESTeCON RF Test Cables
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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!
 The date approacheth when, according to
Western customs, every body needs to stand a vigil against the attempt of another
body to make him or her a fool. That date is of course April 1st, aka, April
Fools' Day. Many of the technical magazine we grew up with - and some still today
- engage in the ruse. Innovator and publisher Hugo Gernsback, who's long list of
accomplishments includes this Radio-Electronics magazine, often contributed
his own wit to the April editions. The usual scheme is to make the article just
authentic enough to be possibly real, while including features outrageous enough
to clue the read that he is being "had." Experienced subscribers knew that the Mohammed
Ulysses Fips byline was sure to deliver an April Fools delight. Here, Mr. Fips
expounds on the newfangled "Electronics
Razor..."
 "Quantum computing has long struggled with
creating
entangled photons efficiently, but a team of researchers has discovered a game-changing
method using metasurfaces - flat, engineered structures that control light. By leveraging
these metasurfaces, they can generate and manipulate entangled photons more easily
and compactly than ever before. This breakthrough could open the door to smaller,
more powerful quantum computers and even pave the way for quantum networks that
deliver entangled photons to multiple users..."
 Here is a chart you don't see every day
- "Temperature Rise in Rigid Waveguide." The company, Engineering
Antenna Systems, of Manchester, New Hampshire, that published the chart in a 1965
edition of Engineering magazine, does not exist anymore. They were probably
bought by someone else, but I could not even find an honorable mention of them in
a Google search. Given the very low attenuation of properly sized and installed
waveguide, it is hard to imagine a temperature rise of 500°F; however, when megawatts
are pumped into it even a couple tenths of a decibel of attenuation per 100 feet
results in a lot of power loss. Noted is how attenuation - and therefore temperature
rise - is greater for frequencies at the lower end of the waveguide's operational
range. Temperature rise numbers are for natural convection in free air...
 Here is an inspiring interview of
Werbel Microwave's Ernest Werbel - a case of pulling oneself up by one's own
bootstraps --- everything RF recently interviewed Ernest Werbel, the Chief Design
Engineer of Werbel Microwave. He is from Livingston, NJ, and got his associates
in EE Technology, at County College of Morris. Ernest completed his Bachelors in
Electronics and Computer Engineering Technology from NJ Institute of Technology.
He founded Werbel Microwave in 2014. Q. Can you tell us about Werbel Microwave?
When did you start the company and how has it evolved over the years? Ernest Werbel:
Firstly, thank you for the opportunity to participate in the everything RF community.
I appreciate everything that Raghav and his team have done for us since the beginning,
getting our products listed on everything RF and featuring our products in the email
blasts... As a child and teen in the 90s, I was always interested in electronics.
When I was very young, a radio was a magical box with a voice. Later, when my grandparents
passed in '97, my parents and I were cleaning out their home in Brooklyn. Among
other things were many old and broken consumer electronic items...
 Today we have
missing persons notices printed on milk cartons and computer-aged
pictures of missing kids on bulletin boards at Walmart, and of course the Internet
with all its various forms of publicity. In 1935, evidently, an electronics magazine
was a proper venue for placing a missing person ad. At the time there was no convenient
and accessible way for family members to reach out to a nationwide audience other
than to place ads in magazines and/or newspapers in remote locations. I thought
it odd to see such a placement in this edition of Short Wave Craft magazine,
but considering the aforementioned, doing so is entirely reasonable for a worried
family. I wonder how much it cost to place the notice? It's heartbreaking, really...
• 2025 Tech Jobs Expected
to Take Off
• Semiconductor
Industry Faces a Seismic Shift
• 76% of
News Consumers Still Use AM/FM
• FCC
Spectrum Rules to Support Advanced Flight Technologies
• Radio
Attracts High Purchasing Power Consumers
 I'm always aware of the old saying that
it is better to remain silent and thought a fool, than to open your mouth and remove
all doubt, but I'll take the risk here. The ARRL's QST magazine has for
decades in the April issue published at least one unannounced "April Fool" item.
I think I found at least two for 2025. While enthusiastically reading "Turn Your
Vertical Antenna into a Rotatable Beam," (p60), it didn't occur to me that this
was the April issue, and I was in awe of Jay Kolinsky's (NE2Q) intuition and creativity
in devising a scheme to get directivity from his standard vertical whip antenna.
By sliding a carbon fiber tube with a narrow slit along the length over top of the
antenna, a 14 dB increase was realized in the direction of the slit. NE2Q has
named his invention the Loof Lirpa Slot (LLS). What's in a name -
Juliet?.
Is a patent in the works?
 The other suspect is the CW Corp. of America's
"Snappy
Training Key," reported on page 95 by Ellwood Brem (K3YV). You need to log in
to read the articles, or borrow a hard copy from a Ham friend.
|
 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...
 In the run-up to World War II and during
the battle, a lot of
plastics
research and production was considered classified defense information. Poly(methyl
methacrylate) (PMMA), also know by the trade names of Plexiglas, Lucite, Crystallite,
and others, was a crucial component for aircraft where the weight and brittleness
of regular glass made it practically useless (and dangerous). A full-page ad by
Shell Oil in this 1942 issue of Life magazine promoted plastic used in a bomber.
When I see this, it reminds me of "It's a Wonderful Life," where Sam Wainwright
offers George Bailey a position in his fledgling soybean-based plastic canopy factory
in Buffalo, New York. Being primarily a petroleum product, plastic was promoted
heavily by oil companies like Shell Oil, Standard Oil, American Oil, partially due
to patriotism, but no doubt also for the profits. Those places, of course, were
part of the "Military-Industrial Complex" identified by President Dwight Eisenhower.
In fact, an Internet search turns up many claims that those same companies conspired
to sell oil to Axis powers prior to America's official entry into WWII on December
7, 1941, when the Japanese bombed Pearl Harbor...
 The probability-based
quantum mechanical model of atoms has been in existence since around 1932 when
Robert Mulliken coined the term "electron orbital." It superseded the Bohr model
that modeled the atom as a proton/neutron nucleus that was surrounded by electrons
orbiting like planets around a star. For many decades thereafter, text books - particularly
those used in beginner level courses - continued to present the Bohr model and only
gave passing reference, if at all, to the quantum model. The Bohr model was and
still is easier for most people to envision, although as time goes on the percentage
of people who even recognize a planetary model is probably rapidly decreasing. This
article from a 1944 edition of Radio-Craft magazine chooses to use the Bohr model
as part of an introduction to electronics. Today, you might need to start from a
lower point and talk about groupies swarming around rock stars for most people...
 I found a copy of the 1941 Radio Engineering
Handbook, by McGraw-Hill Book Company at a Goodwill store. The cover was beat-up,
but the inside pages are all good. The "Mathematical and Electrical Tables" section
has an interesting method for calculating up to the sixth harmonic of any periodic
waveform by dividing the period into twelve equal parts (in time) and noting the
amplitudes at each point - aka "The
Twelve Ordinate Scheme." Those values are plugged into a host of equations that
yield essentially the Fourier coefficients for a 12-element polynomial describing
the curve. The text also provides equations for calculating harmonic content. Calculating
the polynomial coefficients is a simple process of doing iterations of sums and
differences of amplitudes, a la the Fourier analysis. Care must be taken to get
the numbers right or the resulting equation will not reproduce the original waveform.
In 1941, the user needed to look up in a table or find on a slide rule the sines
and cosines of nωt angles associated with each term, then multiply that by the calculated
coefficient. Finally, after all twelve points were figured...
 Once radios in the family car became a standard
accessory, a push ensued to make them cheaper, more reliable, and service-free.
A major Achilles' Heel was the high voltage power supply required to energize vacuum
tubes. Known as vibrator power supplies due to using an oscillator to convert the
battery's 12 DC supply (some autos still used 6 V systems) into AC that could
be transformed up to the 300 volts used by most tubes of the day, most early failures
were attributed to the circuits. They also caused annoying noise in the audio output
if careful filtering and installation was not performed. Having been invented only
a couple years earlier, transistors were being designed into the power supplies,
but
low-voltage tubes were still needed for the electronics. In response to the
demand, low-voltage tubes...
 Here is an unusual twist in waveform recognition
presented by Radio-Electronics' and Popular Electronics' quizmaster,
Robert Balin. If you happen to be a former analog television repairman, then you
will probably recognize the answers based on your many years of diagnosing faulty
horizontal or vertical
sweep circuits. If not, then you might need to strain the "little gray cells"
a bit, as Agatha Christie's premier sleuth Hercule Poirot might say. The instructions
say to assume that if you choose the horizontal sweep sawtooth to be the errant
signal, then assume the vertical sweep sawtooth is correct, and vice versa. Right
off the bat, waveform 8 is unique enough to easily identify the sweep that would
produce it since only one has two repeating components. Most of the others can be
readily deduced, too, by mentally following the x and y points as the "correct"
sweep...
 If you happen to be a retired
television repairman from the era of analog broadcast and cathode ray tube (CRT)
displays, or if you have studiously read the many articles I have posted from vintage
electronics magazines about TV, then you will probably breeze right through this
themed crossword puzzle from a 1958 issue of Radio & TV News. I have
to admit to having done poorly myself, even after having been the one who posted
all that stuff. Just having a general knowledge of electronics doesn't help much
here since all the clues and words are very specific to television circuits. Still,
it's worth the challenge and if nothing else you'll learn a little more about old
time television- it really was a quite ingenious scheme for cramming ...
 The
Underwriter's Laboratory (UL) is an entity that seems to have
been around forever. A lot of people - maybe most people - assume that it is a government
entity. In fact, it is a non-profit organization sponsored by the National Board
of Fire Underwriters (later changed to American Insurance Association, then to APCIA).
Its roots are traceable back to the Chicago World's Fair in 1893. Concern over the
potential fire hazard of Edison's light bulbs was the impetus for the effort. Another
aspect of the UL that a lot of people don't know is that the UL label of approval
is no guarantee that the device works properly, only that is passes standards of
safety as it relates to fire hazards. This article in the August 1955 edition of
Popular Electronics magazine gives a brief history.
 If you like the
radio-themed comics from vintage electronics magazines, then you'll appreciate
the jackpot of them (5) in the July 1945 issue of Radio Craft magazine.
Being the era in which it was published, many of the comics at the time had military-electronics
themes as well. A lot of them are credited to subscribers providing ideas. One of
my favorite features is "Radio Terms Illustrated," where readers write in with suggestions
for how common lingo in the radio realm can have an alternate interpretation. Such
is the case with "Wave Trap" in the first comic. I think Frank Beaven was the illustrator
for all of them. Look in the big list of other technical-themed comics at the bottom
of the page for others which include "Radio Terms Illustrated."
 Back in 2012, I posted a video of the PBS
"Frontline" show (Cell Tower Deaths) that highlighted the dangers cell tower climber
technicians face while working for very low wages. Other news stories since then
have reported on new regulations from OSHA and other agencies that have helped make
the safety issue better, but I haven't seen anything on whether the pay has gotten
any better. There are lots of videos and photos online of
tower climbers
all over the world, but this one showing tower climber Kevin Schmidt making the
ascension to the very top of the now inactive KDLT TV analog broadcast antenna
near Salem, SD, is unique in that the recording was made from a drone platform.
It has more than 12 million views. Capturing this kind of video requires a drone
with a wireless live feed so the pilot...
 Here is a vintage crossword puzzle from
the October 1957 edition of Popular Electronics magazine. Being created at a time
solidly into the semiconductor era, you do not need a knowledge of vacuum tube terminology.
This one contains mostly words relating to electronics similar to the weekly electronics,
math, science, technology, and RF & microwave theme crosswords from RF Cafe.
It won't take you too long to complete...
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...
 Admittedly, the only thing I remember about
Gray Code (aka reflected binary) from college courses is that
successive count values change only one bit per increment, saving power in some
digital circuits. The power savings comes from the fact that, especially for CMOS
circuits, current only flows during the transition of a state change from "0" to
"1" or from "1" to "0." Shaft position encoders were and still are a primary application
of Gray Code switching. If the encoder output digital code is going to be used in
a binary computation system, then there is an advantage in generating a direct binary
("natural") count that does not require a Gray-Code-to-Binary conversion circuit
(or software routine). When the Wayne-George Corporation introduced its paradigm-changing
"Natural Code Non-Ambiguous Optical Encoder" in 1964, those conversion circuits
were probably not simple, compact, inexpensive semiconductor IC's...
 Those of you who have or have had a business
where you employed workers can relate to this article which appeared in a 1952 issue
of Radio & Television News magazine. Never having had that responsibility,
I cannot relate directly.
Small business owners I have known have told me about how their first responsibility
is to pay employees before paying themselves, and no one who has never been in that
position can truly relate to it. What I find interesting in these kinds of vintage
articles is the cost of goods and services back in the day, with the help of the
Bureau of Labor Statistics' Inflation Calculator. For instance $100 per week ($5,200/year)
income back in 1952 is supposedly equivalent to $1,024 per week ($53,248/year),
which really is pretty good. I don't know how generous fringe benefits were in 1952
compared to today...
 This could be one of the earliest reports
of
mobile communications between a private automobile and a home
base station. Using a personally designed and installed 5-meter transceiver both
at home and in his car, Mr. Wallace is able to talk to his 12-year-old son
on the way from work. My guess is that in 1935 there were not too many traffic jams,
even in Long Beach, California, so it is doubtful that was the cause for his announced
expected later-than-normal arrival home. The article states the automobile power
supply needed to produce 300 mA of current at 525 V, which is ~160 W
per Ohm's law, which seems unlikely considering car batteries were 6 V at the
time...
 "Fair
Trade" was a policy established in the post-WWII era in response to what consumer
retail groups considered business-ruining cost cutting by dealers who offered to
sell products at or barely above cost in order to steal profit from other stores.
So-scheming stores planned to make up for the low profit margin with high sales
volumes. Doing so drove a lot of the local competition out of business, leaving
the crafty dirty dealers to later raise prices. Stores that had manufacturer-sanctioned
service shops often got screwed because they were obligated to repair items like
TVs and radios that were bought from another dealer who did not do service work.
Profit margins on repair work - at least from honest shops - were typically very
low, so the owners depended on new product sales to help raise the bottom line...
 It has been a while since I saw the
quotient rule for derivatives applied. Probably the last time was in a college
text book, because I'm pretty sure I haven't had the occasion to use it since then
- except maybe back in the days when I was writing my RF Workbench software and
needed to derive closed form solutions for group delay in filters. This 1933 article
from Radio News magazine presented the quotient rule as part of a discussion for
finding the impedance of a load for maximum power transfer. Pure resistances were
used in the example, but the method applies as well to complex impedances...
 Here is a fairly simple
quiz on AC circuit analysis. If you are not already comfortable with adding
series and parallel circuits containing resistors, capacitors, and inductors, you
will appreciate the simple formula presented that will keep the sweat level down
;-) . An even simpler form that solves explicitly for the four variables are
as follows: VTotal = √ [(VL - VC)2
+ VR2]
VR = √ [(VT)2 - (VL - VC)2]
VL = VC + √ [VT2 - VR2]
VC = VL - √ [VT2 - VR2]
OK, pick up your pencils... now...
 "Necessity is the mother of invention,"
is a common saying that proves itself to be particularly true in times of war. World
War II launched scientists and engineers belonging to both the Axis and the
Allied powers into inventive frenzies in their efforts to hasten an end to hostilities;
of course each side also wanted to be the victor. We all know how the story ended.
Although some countries were not immediately able to capitalize on their countrymen's
technical advances, within about a decade normalized relations had been established
between former foes, and the exchange of products, services and scientific information
proceeded. Some discoveries were deemed too valuable to national security and were
therefore not divulged even, in some instances, to friendly nations. Many scientists
consider themselves to be "citizens of the world" and vehemently object to not sharing
all available knowledge out of a belief...
 Little did Ham radio operators know in April
of 1941 when they were enthusiastically buying equipment for their shacks that a
year later the Federal Communications Commission (FCC) would ban them from broadcasting
from their transmitters. This advertisement for a high-end Hallicrafters receiver
appeared in the April issue of Radio News magazine. Part of the feature
definition includes "calibrated bandspread
inertia controlled," and "micrometer scale tuning inertia controlled." I'm not
sure what the "inertia controlled" part is, unless it refers to how massive metal
disks were sometimes installed inside the chassis on the tuning shaft in order to
give a more solid feel to the control knob, as well as to enable the dial to be
spun and released to rapidly move through a large distance between adjustment points...
 When I began reading this piece I wasn't
sure whether it was reporting on interference caused to amateur radio operation
or
interference caused by amateur radio operation. It turns out to be the latter.
Ever since radio operation began in the days of Marconi, unintentional interference
has been a problem. The problem has always been a combination of improper transmitter
and/or receiver filtering. Electromagnetic spectrum regulatory agencies attempt
to assess and address interference through operational band assignments for particular
segments of the spectrum, including how much residual (unintentional) power can
be emitted outside of band or within a defined power mask. Amateur radio operators
are often the first group to be suspected of causing interference, no doubt due
to the "amateur" part of their moniker. In truth, many amateurs are some of the
most knowledgeable and responsible users of the airwaves... |
