I have written
before about the love-hate relationship a lot of the buying public had with
television and radio repair shops and repairmen - similar to car owners and
mechanics. Lots of jokes and skits (what today is termed a "meme") were created
back in the heyday of in-home entertainment to make light of the situation.
These four
electronics-themed comics from a 1962 issue of Radio-Electronics
magazine are typical examples. The one from page 111 alludes to an issue that
would almost never be seen today on a TV, unless maybe the AC power supply was
on the fritz. A composite analog broadcast signal contained vertical and
horizontal sync[ronization] components which...
"Electrostatic
discharge (ESD) protection is a significant concern in the chemical and electronics
industries. In electronics, ESD often causes integrated circuit failures due to
rapid voltage and current discharges from charged objects, such as human fingers
or tools. With the help of 3D printing techniques, researchers at Lawrence Livermore
National Laboratory (LLNL) are 'packaging' electronics with printable elastomeric
silicone foams to provide both mechanical and electrical protection of sensitive
components. Without suitable protection, substantial equipment and component..."
Mr. Bob Davis, a seemingly endless
source of little known and/or long forgotten
historical radio and television
technical trivia, apprised me of this short segment from the 1960s Dragnet
television series, starring Sgt. Joe Friday. It features a guy, who turns out to
be a ... well, I won't spoil it for you ... who proudly professes his thirty
year career as a radio repairman. "...started back in the days of the old Crosleys, Atwater-Kents, Farnsworths.
Those were real radios, well built, well designed. Nothing cheap about any of
them. They didn't have transistors in those days, just tubes as big as light
bulbs. That meant heavy chassis, heavy transformers, and we didn't fix them by
simply slapping in a new part, either. We fixed the old parts. I wish...
A new word has been added to my personal
lexicon: "sphenoidal."
Author John Kraus used it to describe the wedge shape of a
corner reflector. The Oxford Dictionary defines "sphenoid" thusly: "A compound
bone that forms the base of the cranium, behind the eye and below the front part
of the brain. It has two pairs of broad lateral "wings" and a number of other projections,
and contains two air-filled sinuses." This "square corner" configuration - essentially
a "V" shape, is shown to exhibit up to 10 dB of gain while being relatively (compared
to a parabolic reflector) insensitive...
Albert Einstein's general theory of relativity,
published in 1915, fundamentally reshaped the way scientists understand gravity,
space, and time. It extended his 1905 special theory of relativity, which described
how the laws of physics are consistent for all observers in uniform motion and how
light's speed is constant in a vacuum. However, the special theory did not address
accelerating reference frames or gravitational forces. Einstein's general theory
tackled these limitations by proposing that gravity is not a force in the traditional
sense, but rather a curvature of spacetime caused by mass and energy. This profound
insight would alter the course of 20th-century physics, influencing cosmology, black
hole theory...
"The growing use of artificial intelligence
(AI)-based models is placing greater demands on the electronics industry, as many
of these models require significant storage space and computational power. Engineers
worldwide have thus been trying to develop neuromorphic computing systems that could
help meet these demands, many of which are based on memristors.
Memristors are electronic components that regulate the flow of electrical current
in circuits while also 'remembering' the amount of electrical charge that previously
passed through them. These components could replicate the function of biological..."
Reading through the news items in the vintage
electronics magazines provides a mixture of important historical facts and figures
along with some predictions on the future of the industry. Some of the predictions
turn out to be amazingly accurate, even though in retrospect they might seem obvious.
Take, for example, Sylvania VP Dr. Robert Castor's foresight about how, "the future
growth of the semiconductor industry lies in a major switch from the production
of individual components to solid-state subsystems that can be used as building
blocks in electronic designs." "Well of course," you might be temped to say; however,
at the time there were still significant hurdles to overcome related to material
purity, wafer size, photolithography...
Reactel has become one of the industry leaders
in the design and manufacture of RF and microwave filters, diplexers, and sub-assemblies. They
offer the generally known tubular, LC, cavity, and waveguide designs, as well as
state of the art high performance suspended substrate models. Through a continuous
process of research and development, they have established a full line of filters
of filters of all types - lowpass, highpass, bandpass, bandstop, diplexer, and more.
Established in 1979. Please contact Reactel today to see how they might help your
project.
2012 came and went more than a decade ago.
The date was 50 years in the future back in 1962 when Radio-Electronics
magazine editor Hugo Gernsback asked industry leaders to cogitate on possibilities
of the
state of electronics in 2012. Let's see how they did. One guy predicted our
communications would be in the 100 THz to 1,500 THz band, using 2 decimeter
antennas. Nope. Another believed we would be communicating with aliens on a regular
basis. A military dude partly hit the mark by predicting 2- and 3-year-olds would
be sitting in front of "televideo screens" (cellphones) learning Esperanto and "other
basic studies." Bell Labs believed most audiovisual material, along with commerce,
would be done electronically; i.e., the World Wide Web. I'm not quite sure how to
interpret the IT&T guy's prediction of replacing microwave space transmission
with light wavelength waveguide transmission. Seems bassackward to me...
Here is a unique approach to discouraging scam
callers. A lot of scam calls are themselves AI, so can one AI detect and aviod another?
"Gangster
Granny! Meet Daisy: O2's new weapon against scammers. O2 has unveiled its new,
unique weapon in its fight against scammers: Daisy, an AI-powered assistant designed
to keep fraudsters talking and waste their time. As part of Virgin Media O2's 'Swerve
the Scammers' campaign, Daisy's mission is to distract scammers with realistic,
rambling conversations, helping protect potential victims while raising awareness
about fraud. Her lifelike conversations, peppered with stories about family or hobbies
like knitting, have kept fraudsters on the line for up to 40 minutes..."
Albert Einstein's
special theory of relativity, a milestone in physics, transformed our understanding
of space, time, and energy (mass). The theory, published in 1905, stemmed from Einstein's
efforts to resolve inconsistencies in classical physics, specifically between Newtonian
mechanics and electromagnetism as formulated by James Clerk Maxwell. By reconceiving
space and time as interconnected and relative to the observer's frame of reference,
Einstein established a framework that had profound implications for science and
technology. To understand how this groundbreaking idea emerged, one must consider...
Werbel Microwave's Model WM2PD-0.5-26.5-S
is a wideband 2-way in-line power splitter covering of 500 MHz to 26.5 GHz with
excellent return loss, low insertion loss, and high isolation performance. With
ultrawideband performance, amplitude balance is typically 0.24 dB and phase
unbalance is typically 2.6°. Insertion loss is low for the bandwidth, coming in
at a typical 1.2 dB above 3 dB splitting loss. Return loss 16 dB
typical. Isolation 18 dB typical. The device is precision-assembled and tested
in the USA...
If you wanted a career as an
electronics technician at the end of World War II, the world was your oyster
- so to speak. Electronics and communications trade magazines and publications like
Mechanix Illustrated and Popular Science ran a plethora of ads
monthly that offered unlimited opportunity to men seeking a career servicing the
burgeoning market of postwar technological marvels. Even though the enclosures were
not yet being marked with "No user serviceable parts inside," that fact was most
people were not qualified - nor did they want - to monkey with the guts of radios,
televisions, and other household appliances... (I provide a simulation to show the
true zener diode circuit output)...
Take time out of your busy workday to look
at these three
electronics-themed comics from the February 1962 issue of Radio-Electronics..
The page 32 comic reminds me of sometime in the late 1970s while working as
an electrician (prior to enlisting in the USAF) when I was doing side jobs, and
a guy had me wire up a receptacle for his big 25" screen (CRT) which he had mounted
in a wall, with the chassis sticking out the back. It was in an upstairs room in
a Cape Cod style house with lots of room behind the wall. He was a "man cave" pioneer
with a full suite of high quality audiovisual equipment - even a Betamax machine!
The page 81 comic exhibits the irony that would have existed in the day if
American-made electronics equipment had been promoted in Japan, which they probably
were not. In 1962, Japanese...
Admittedly, I mostly posted this because
of the drawing. "While
direct-to-cell (D2C) satellite communications were a big topic at the recent
Brooklyn 6G Summit, the technology is already here, well before 6G's anticipated
2030 arrival. Apple and Google already offer D2C emergency messaging, and Starlink,
T-Mobile and others are anticipated to follow. D2C satellite communications will
be well established when 6G arrives. The 3GPP froze a 5G specification for Non-Terrestrial
Networks (NTN) in Release 17 in March 2022, which means that NTN-compatible chips
and components should be available now or soon. SpaceX has reduced the cost..."
The subtitle of this article from a 1971
issue of Popular Electronics magazine, "From
Quackery to Speculation to Programmed People," could to some extent still be
applicable even though the author evidently meant to put an end to the "quackery"
and "speculation" part of it. Indeed, a lot of advancement has been made in the
fields of electrostimulation of weak or/or paralyzed muscles, healing of certain
types of soft and hard tissues, suppressing sporadic muscle twitching and epileptic
seizures, and other malady diagnosis and relief. Specifically tuned microwave frequencies
have proven useful in healing and symptom relief as well. As with most articles
on medical procedures, I cringe at some...
Anatech Intros 3
Filter Models for November
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
C-band cavity bandpass filter models have been added to the product line, including
a 4994 MHz BPF with a 50 MHz bandwidth, a 4950 MHz BPF with a 10 MHz
bandwidth, and a 5785 MHz BPF with a 100 MHz bandwidth. 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...
• 5G
Is 42% of Fixed Wireless Access (FWA) in 2024
• Robert Dennard,
DRAM Pioneer, Dies at 91
• TSMC's Energy
Demand Drives Taiwan's Geopolitical Future
• Semiconductor
Packaging Market on 5.6% CAGR 'Till 2028
• Altering
Asteroid Trajectories with Nuclear X-Rays
Albert Einstein, one of the most renowned
physicists in history, was born on March 14, 1879, in Ulm, in the Kingdom of Württemberg,
part of the German Empire. His father, Hermann Einstein, was an engineer and salesman
who ran an electrochemical factory, and his mother, Pauline Koch, managed the household
and supported her son's education. Einstein had one sister, Maja, who was born in
1881 and with whom he had a lifelong close relationship. Einstein's extended family
included several relatives who would play various roles in his life, both personally
and professionally. His early family life was comfortable, though his parents moved
frequently as they sought economic stability. Hermann Einstein's business ventures
had varying success, and eventually, the family moved to Italy in 1894...
Here is the second part of a series of articles
about
stepping switches appearing in 1967 issues of Radio-Electronics magazine.
A standard (at the time) dial rotary phone was used as a familiar example in the
part one. It delivers a single pulse for each number / letter set from 1, 2 (ABC),
3 (DEF), through 9 (WXY), 0 (Operator). On some phones, you can hear the clacking
of the switch contacts as the spring-loaded dial rotates from the selected number
back to home position. The stepping action as the result of dialing occurs at the
telephone system switching and call routing equipment at central locations. There,
stepping switches increment with each pulse received, and when the full number of
pulse sets have arrived, the circuit is complete and the call put through to ring
the phone...
"Results are published, and the numbers
are in. They paint a picture of a very active
2024 ARRL
Field Day. Nearly 1.3 million contacts were reported during the 24-hour event.
That is up from 2023's 1.25 million contacts. That's likely indicative of the continued
rise of Solar Cycle 25 leading up to the event, but more people also participated
this year. Entries were received from all 85 ARRL and Radio Amateurs of Canada (RAC)
sections, as well as from 27 different countries from outside the US and Canada.
'It is encouraging to see a rise in participation year to year,' said ARRL Contest
Program Manager Paul Bourque, N1SFE. 'ARRL Field Day is amateur radio's premier
event, and the hams turned out for it..."
After searching for the first mention of
Nikola Tesla in U.S. newspapers, I performed a similar search on
Albert
Einstein, again using editions available in the NewspaperArchive.com database.
I was utterly surprised to find it in a 1919 issue of the The New York Times.
His theory of Special Relativity was published in 1905 and his theory of General
Relativity was published in 1915, so it took The NY Times four years to
mention it. There is a reference to Dr. Einstein's' work on relativity in a 1915
edition of The Manitoban, from Winnipeg, Canada. The NY Times article
is an actual interview with Albert Einstein, wherein at one point it is stated that
there were perhaps only a dozen people in the world at that time who understood
general relativity. Interestingly, Einstein uses the term "difform motion" to describe...
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 model
AMP2103P-LC, dual-mode (CW & pulse) amplifier covering 800 to 3200 MHz.
1000 watt peak pulse power, or 500 watts CW. Ideal for automotive pulse/radar
EMC-testing & commercial applications. Pulse widths to 560 μsec, duty cycle
to 10%, 60 dB gain, and outstanding pulse fidelity. Monitoring parameters for
forward/reflected power in watts and dBm, VSWR, voltage, current, and temperature,
with unprecedented reliability and ruggedness in a compact 7U chassis...
Sally Mason was the soldering iron-wielding
heroette (heroine sounds too much like the narcotic) of Nate Silverman's "Sally,
the Service Maid" series that ran in Radio-Craft magazine during the
years of World War II. As I noted in the previous episode, many of the nation's
women were left behind to run their husband's, father's and/or son's electronics
sales and repair businesses when they went off to save the world from aggressive
Communists, Socialists, Maoists, Nazis, and other nasty types. Some of those ladies
had already become very adept at troubleshooting, component replacement, and aligning
radio and television sets, while some were left to learn at the School of Hard Knocks.
Sally's father, Gus Mason...
Crane Aerospace & Electronics' products
and services are organized into six integrated solutions: Cabin Systems, Electrical
Power Solutions, Fluid Management Solutions, Landing Systems, Microwave Solutions,
and Sensing Components & Systems. Our Microwave Solution designs and manufactures
high-performance
RF, IF and millimeter-wave components, subsystems and systems for commercial
aviation, defense, and space including linear & log amplifiers, fixed &
variable attenuators, circulators & isolators, power combiners & dividers,
couplers, mixers, switches & matrices, oscillators & synthesizers.
The AN/MPN-13|14 mobile radar system I worked
on while enlisted in the U.S. Air Force was designed and fielded around the time
this
Electronic Navigation in Flight article appeared in a 1962 issue of Radio-Electronics
magazine. It had been upgraded a few times by 1979 when I was in Air Traffic Control
Radar Repairman technical school at Keesler AFB, Mississippi; however, the original
system did not featured a Doppler capability. The fully RF analog system could not
provide air traffic controllers with speed data, but it did use physical mercury
delay lines to provide a stationary target (ground, and to some degree, rain, clutter)
cancellation by inverting and summing a real-time radar...
Decisions, decisions, decisions. As the
title states, color television manufacturers were, in 1965 when this Electronics
magazine article was published, 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...
"At 8:30 p.m. on 16 May 1916, John J. Carty
banged his gavel at the Engineering Societies Building in New York City to call
to order a meeting of the American Institute of Electrical Engineers. This was no
ordinary gathering. The AIEE had decided to conduct a live national meeting connecting
more than 5,000 attendees in
eight cities across four time zones. More than a century before Zoom made virtual
meetings a pedestrian experience, telephone lines linked auditoriums from coast
to coast. AIEE members and guests in Atlanta, Boston, Chicago, Denver, New York,
Philadelphia, Salt Lake City, and San Francisco had telephone receivers at their
seats so they could listen..."
|
Here is the electromagnetic wave section
of the "Wireless Networking in the Developing World," book (open source). "Wireless
communications make use of
electromagnetic
waves to send signals across long distances. From a user's perspective, wireless
connections are not particularly different from any other network connection: your
web browser, email, and other applications all work as you would expect. But radio
waves have some unexpected properties compared to Ethernet cable. For example, it's
very easy to see the path that an Ethernet cable takes: locate the plug sticking
out of your computer, follow the cable to the other end, and you've found it! You
can also be confident that running many Ethernet cables alongside each other won't
cause problems, since the cables effectively keep their signals contained within
the wire itself. But how do you know where the waves emanating from your wireless
device are going..."
The decade of the 1960's was an exciting and fast-moving
time for electronics, being that it was the beginning of a major paradigm change from
vacuum tubes to transistors, from discrete circuit components to integrated circuits,
and from point-to-point wiring to printed circuit boards. Computers were on the verge
of moving out of university labs and corporate research and development centers to small
businesses and retail headquarters. Electronic calculators were replacing mechanical
calculators. Digital systems were replacing analog systems.
Electronics training schools were in their collective heyday. Training
prospects lined up in droves and competed to gain acceptance into the
institutes. Home-study courses provided theory and hands-on building and
troubleshooting...
When looking a these vintage
electronics-themed comics from Radio-Electronics magazine (and others),
it probably is a case of "you had to have been there" to appreciate the humor in
them. In a world of 24/7 broadcasting of every TV channel, the first comic wouldn't
even make sense to someone who was born after about 1990, after which time most
local over-the-air broadcast stations signed off at 1:00 or so, played the National
Anthem, and then displayed a test pattern until about 6:00 am. The second comic
is from the era of high voltages inside radio and TV chassis for vacuum tube plates
and CRT accelerator grids. That big bulky thing the guy in the last comic is carrying
is a thing called a cathode ray tube (CRT), which old people used to use...
The final 1965 edition of Electronics
magazine produced reports on the status of electronics markets in
Western Europe and Russia. This is the opening statement proclaiming "The
boom continues." Separate reports are included for West Germany (the Berlin Wall
was still up then), the United Kingdom, France, Denmark, Austria, Sweden,
Belgium, Switzerland, the Netherlands, and Italy are covered in separate
sections. Russia, although obviously not part of Europe, is also covered. All
will be posted within the next couple weeks for the benefit of historians...
One aspect of advertising on the RF Cafe
website I have not covered is using
Google AdSense.
The reason is that I never took the time to explore how - or even whether it is
possible - to target a specific website for displaying your banner ads. A couple
display opportunities have always been provided for Google Ads to display, but the
vast majority of advertising on RF Cafe is done via private advertisers. That is,
companies deal with me directly and I handle inserting their banner ads into the
html page code that randomly selects and displays them. My advertising scheme is
what the industry refers to as a "Tenancy Campaign," whereby a flat price per month
is paid regardless of number of impressions or clicks. It is the simplest format
and has seemed to work well for many companies. With nearly 4 million pageviews
per year for RFCafe.com, the average impression rate per banner ad is about 225,000k per
year (in eight locations on each page, with >17k pages)...
Today's
consumer electronics (CE) industry has an estimated value of $354
billion per a Statista report (a high number compared to others I located). In 1957,
according to this article in Radio-Electronics, the market value was reported to
be $13.7B ($121B in 2014 dollars per the BLS inflation calculator). The world population
in 1957 was 2.89B and grew to 7.10B by 2013 (per Census.gov). That means population
increased by a factor of 2.45 while the CE industry grew by a factor of 3.05. Within
the margin of error of marketing expert estimates, that represents essentially flat
growth. Fret not, though, because while the total spending on consumer electronics
per capita might have been flat over a span of nearly 60 years, the effective cost
per electronics product and the vastly improved functionality and reliability of
electronics products has increased by a much larger factor ...
Joe Cahak, owner of Sunshine Design Engineering
Services, has submitted another fine article for posting here. Joe has many years
of automated RF testing experience to leverage when writing this paper on making
measurements with scattering parameters (S-parameters)
involved. He begins, "In many RF and Microwave measurements the S-Parameters are
typically expressed in dB (decibels) Magnitude units and Degrees in the polar coordinate
system. Network and Vector Network Analyzers and Spectrum Analyzers all measure
with voltage ratio measurements, so to convert to dB in terms of volts we must use
the following equation. The Spectrum Analyzer is a frequency discriminating detector
that detects the voltage for the signal. It will give the amplitude of signal as
a function of frequency. It is scalar in measurement dimension magnitude vs. frequency.
Displayed units are typically expressed in units of power (dBm). The Vector Network
Analyzer measures complex magnitude and angle of RF signals vs. frequency. By using
reference signals to calibrate the test system response and setting up a reference
frame for the measurements, the instrument can measure the amplitude and phase angle
of the AC-RF signal for each frequency it is tuned to. Displayed units are typically
expressed..."
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...
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...
It is important to concentrate your transmitter
power into the proper beam if you wish to deliver the best signal to the other fellow's
receiving antenna. This has logically led to the popularity of the Yagi beam antenna
on the higher-frequency amateur bands. A beam antenna for the 80-meter band should
have a 140-foot reflector and a 77-foot boom on a 250-foot tower. This makes the
beam antenna impractical for the 80-meter band, and even for 40-meter operation
a full-size Yagi is a forbidding structure to the neighbor's narrow-minded view
- even a well-trained XYL might view such a monster beam with alarm. There is no
easy solution to the need for a good DX antenna at low frequency, but the conical
monopole antenna may be of interest to the more eager radio amateur as a more practical
solution. The
conical monopole antenna is a base-fed vertical antenna that has an omni-directional
pattern in azimuth but with an elevation...
"Ground
is ground the world around," is an oft repeated saying when talking about making
electrical connections to Earth ground. In a general sense that is true, especially
when referring to electromagnetic radio signals and antenna systems that are in
some manner dependent on the common connection. However, when you are working within
the confines of a localized electronic circuit such as on a printed circuit board
or inside a chassis, there is no guarantee that without proper precautions ground
is not at the same potential everywhere. Poor (high impedance) soldered, crimped,
and bolted connections are among the prime offenders that cause voltage differentials
to arise between points intended to be equipotential. RF frequency signals are particularly
sensitive to even a minor divergence ...
If
subjects pertaining to electronics - particularly vacuum tubes - are like music
to your ears, then this poem entitled "What Is It?," from the February 1943 edition
of QST, should suit you just fine. The rhyming words are supplied by author
Frank Judd; you just need to supply the harmony. You might recognize paraphrasing
of other familiar works such as Longfellow's "Paul Revere's Ride." Poems like this
one were actually quite common back in the day. In fact if you look through the
list of articles that I have posted from vintage QSTs, you will find about
a dozen...
RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running
series, RF Cascade Workbook. Chances are you have never used a spreadsheet
quite like this (click
here for screen capture). It is a full-featured RF system cascade parameter
and frequency planner that includes filters and mixers for a mere $45. Built in
MS Excel, using RF Cascade Workbook is a cinch and the format
is entirely customizable. It is significantly easier and faster than using a multi-thousand
dollar simulator when a high level system analysis is all that is needed...
Do you remember seeing a cool Doodle on
the Google search page and would like to find it again? Would you like to see not
only the Doodle that piqued your interest, but ALL of the Doodles that Google has
ever published? You can do that, but what might be more useful would a page full
of all the technology- and science-related Doodles (click large image below) or
some other specific topic. Fortunately, there is an easy way to find what you want
by going to the Google website and typing "google doodles"
into the search box, or just go to www.google.com/doodles. Once you get there, enter
the specific event that interests you. Since some events have Doodles in more than
one year, add a year to your search to narrow down returns...
I challenge you to find a calculus lesson
in a modern-day electronics magazine. In 1932, not all that long after Isaac Newton
developed differential calculus (that's a joke), Radio News magazine ran
a series of "Mathematics in Radio" articles that included, among other topics,
a few lessons in calculus. Anyone who has taken college-level science or engineering
courses knows how indispensible calculus is in working out many circuit, physics,
and chemistry problems. My appreciation for calculus came when I realized that it
actually allowed me to derive the kinds of standard equations that are commonly
seen in lower level applications. For instance, if you needed to know the volume
of a sphere, you could look up the familiar Volume = 4/3 π r3
formula, or you could write the equation...
The
battle between the serviceman and the customer is epic. The serviceman
knows the customer is out to cheat him of his rightful due for expertise and availability,
and the customer knows the serviceman will try to inflate the bill to finance his
exorbitant lifestyle. This story from a 1945 edition of Radio-Craft is
a humorous take on the subject at first glance from the customer's perspective,
but after reading it you might ascertain that it is really from the serviceman's
perspective. An article from a 1957 edition of Radio News magazine
titled "Strategy for C.O.D. Service" was written as serious advice to servicemen
to avoid being ripped off by customers typified by the one ostensibly penning this
article...
This
RF Cafe Engineering & Science Crossword Puzzle contains at
least 10 words from headlines posted on the homepage during the week of July 29
- August 2, 2019 (marked with an asterisk*). These custom-made engineering and science-themed
crossword puzzles are done weekly for the brain-exercising benefit and pleasure
of RF Cafe visitors who are fellow cruciverbalists. Every word and clue - without
exception - in these RF Cafe puzzles has been personally entered into a very large
database that encompasses engineering, science, physical, astronomy, mathematics,
chemistry ...
Any time I see
an article that references causing limb movements by poking the brain with electrical
signals, I think of the old The Far Side comic. Artist Gary Larson drew quite
a few hilarious operating room scenarios.
Electrocution is of course not a laughing matter - unless it happens to someone else
and it is not serious and no harm is done. Then - and only then - can it be funny. I've
laughed at myself many times after receiving a good jolt due to stupidity. Sometimes
after such an experience I wonder how I never killed myself from getting zapped as the
result of being too lazy to turn off a circuit breaker before servicing a light switch
or receptacle. The sad thing is that I'll probably do it again some day...
An alternate title for this article that
appeared in a 1969 issue of Radio-Electronics magazine could have been,
"How
to Build a J-K Flip-Flop." Author Leonard Geisler takes the reader through a
step-by-step assembly of a functional J-K flip-flop using a collection of 1- 2-
and 3-input NAND gates. The 1-input NAND, in case you are wondering, is used as
an inverter. The piece reads like an in-depth first-semester electrical engineering
technician course textbook. In the process of building the J-K, an R-S (reset/set)
flip-flop is described. Nowhere does Geisler offer an explanation of from where
the "J" and the "K" input labels come. According to electrical engineer Sourav
Bhattacharya blog, it was Dr. Eldred Nelson of Hughes Aircraft who first coined
the term J-K flip-flop...
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...
60 years ago, when this article was originally
published in Popular Electronics magazine, most computers were constructed
either of gears or of vacuum tubes. The Univac in the photo below was a breakthrough
for having been
built entirely of transistors. Even with its "compact" size compared to is successor
the ENIAC, the total computational power and programmability was orders of magnitude
less than that of my handheld calculator, whose size is largely dictated not by
the volume of the electronic circuits, but by the size of the display and the need
for input keys larges enough to press reliably. Doesn't the photo of Pascal's calculator
of 1642 look like it could be a modern 19" rack-mount chassis, complete with handles?
Sending telegraph messages, whether by wire
or wireless means, has always been expensive, particularly considering charges are
determined by the character (letter, number, symbol). Accordingly, the Shakespearean
line from Hamlet declaring that "brevity is the soul of wit" can be reworked to
"brevity is the soul of economy." A telegraph wire, unlike a telephone call, is
a legally binding communiqué, as is of course a written letter, but a telegram is
immediate transmission of information for time-critical messaging. A series of "commercial codes" were developed enabling senders to save often
significant money by sending multi-character codes that represented entire phrases
and/or sentences. What struck me about this article that appeared in a 1948 issue
of The Saturday Evening Post is how, following a court case involving how the inadvertent
swapping of two character positions in a code...
This quiz is based on the information presented
in
Handbook of Dielectric and Thermal Properties of Materials at Microwave
Frequencies, by Theodore Anderson. This book is a wealth of information
of dielectric characteristics of biological tissues in plants, animals, as well
as for ceramics, soils and minerals. Particular attention is paid to properties
in the ISM frequency bands. Extensive sources for similar studies are provided.
All RF Cafe quizzes would make perfect fodder in employment interviews for technicians
or engineers - particularly those who are fresh out of school or are relatively
new to the work world. Come to think of it, they would make equally excellent study
material for the same persons who are going to be interviewed for a job.
Are you between 16 and 17½ or between
26 and 35 and not in uniform? Are you 1-C or mildly 4-F or otherwise ineligible
for military service? Are you interested in a radio operating job in direct support
of the war effort? Then there's a place for you in the
U. S. Maritime Service. If you hold a commercial radio-telegraph
second or higher-grade license, so much the better. But you don't need a ticket
to start with; in fact, you don't need any previous radio training whatsoever. The
Maritime Service will train you. It will make a proficient merchant marine radio
operator out of you at one of the nation's finest operator schools - with pay! This
is an opportunity described several times before in QST. It is time now for the
story to be told again...
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, and
that would work out to ~26 A. My question is whether little Billy possessed
a license permitting him to talk back to dear old dad from the home station? If
not, it really doesn't matter at this point since there is probably some statute
of limitations that absolves him from prosecution...
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 ... |