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 This custom
Communications Engineering crossword puzzle contains some words particular to
radio, radar, analog and digital circuits, components, and other tech-themed words
and clues. Each week for two decades I have created a new technology-themed crossword
puzzle using only words (1,000s of them) from my custom-created lexicon related
to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will
never find among the words names of politicians, mountain ranges, exotic foods or
plants, movie stars, or anything of the sort. You might, however, find someone or
something in the otherwise excluded list directly related to this puzzle's technology
theme, such as Hedy...
 The "Monthly Review" column appearing in
Radio-Craft magazine was an assorted collection of news tidbits about
electronics and communications industry happenings, similar to
contemporary magazines. Looking back to 1947, the world was hopeful about the future
as World War II was finally over and even the loser countries were focusing
on how their societies would be shaped by technology and lessons learned in the
preceding seven to ten years (depending on when a country entered the war). Two
items here are particularly interesting because they refer to ongoing research into
large screen televisions and video phones (aka "televisers"). Large screens at the
time meant either...
 One of the Notable Tech Quotes which has
appeared on RF Cafe is, "The nice thing about standards is that you have so many
to choose from," by computer scientist Andrew Tanenbaum. In the middle of the last
century, a change in the fundamental understanding of current flow precipitated
what has become a very large opportunity for people to misunderstand descriptions
of
current direction caused by a difference in voltage potential
(voltage) - depending on the era a particular description was written. Beginning
with Benjamin Franklin, electron current flow was assumed to be from positive to
negative, ostensibly but incorrectly, because a positive thing must contain an excess...
 "Fortune reports that Elon Musk's SpaceX
and Tesla are constructing Terafab, a chip manufacturing complex that Musk says
will become the largest and most valuable building on Earth. 'Terafab
Texas will be the largest and most valuable building on Earth by far. And it
will be stunningly beautiful,' Musk wrote on X. The New Century Global Center in
Chengdu, China, currently holds the record for the world's largest building at about
18.9 million square feet. Terafab's planned 100 million square feet would exceed
that by more than five times. Texas Gov. Greg Abbott (R) said in a press release
that 'the first phase of the Terafab project represents a capital investment of
more than $16.8 billion and will create 3,000 new jobs...
 Computer analysis in 1976 was a job performed
on a corporate, university, or government mainframe. Radio Shack's TRS-80 came
out in 1977, but it did not have the capacity to calculate and plot antenna gain
charts like the one in this QST article. Yes, an ambitious programmer could
write the code necessary to perform the double integrals presented in the article,
but to do all the figuring needed to create all the graphs in Figure 4, the job
would just about be finishing up today - and that's not too much of an exaggeration.
For some reason the authors never mention what computer was used or where it was
based. When I saw the title of "Loops vs.
Dipole," I expected the loop to be...
 Even with having been granted more than
400 patents in his lifetime, and being a major player in the realms of energy, data
storage, and semiconductor research and manufacturing, you - as well as most people
- have probably never heard the name
Stanford Ovshinsky. He was somewhat of a celebrity in the 1960s
and 1970s when working hard to promote his concept of "glassy semiconductors," -
aka Ovonic devices. Ovonics are amorphous materials that are used for making switches
for digital logic and memory devices. Either the Ovshinsky process did not pan out
for high volume commercial production or some other technology displaced the what
it was hoped to dominate...
 If I told you that Lester William Polsfuss
is widely credited with being a major player in the pioneering of electric guitars
due to his solid-body (no acoustic resonance chamber) designs, you might wonder
where I came up with that claim. However, if you know that Mr. Polsfuss is the surname
of Les Paul, then you would quickly agree. As if being a popular musician and, along
with wife Mary Ford, selling millions of records wasn't enough, Les Paul was
also an experimenter and inventor in the electronic music realm. This article entitled
"Les Paul: Technician and Musician" appeared in a 1958 article
in Radio-Electronics magazine, and was at the time a contemporary look
inside his...
 Sam Benzacar, of Anatech Electronics, an
RF and microwave filter company, has published his August 2026 newsletter that,
along with timely news items, features his short op-ed titled "Filtering
for Quantum: A Problem No One's Talking About." Sam aptly points out that as
quantum computers scale in size, specialized laboratory-built components become
both expensive and a schedule liability for development efforts. When a handful
of qubits was considered breakthrough-amazing, building all the parts in-house made
sense since processes and materials were being invented in the process of doing
so. However, at the point when thousands of filters, amplifiers, and other types
of components routinely manufactured...
 Georg Simon Ohm's discovery of the relationship
between voltage, current, and resistance revolutionized our understanding of electrical
circuits. Ohm's Law provided a simple, yet powerful mathematical tool that has become
essential to both theoretical physics and practical engineering. Although it was
initially met with skepticism, Ohm's perseverance and commitment to his scientific
work ultimately transformed the way we interact with electricity, influencing technologies
that define the modern world. His legacy lives on not only in the equation that
bears his name but also in the unit of electrical resistance - the ohm - that honors
his contributions to science...
 When you think about it, the speed at which
a human being is able to accurately copy
Morse code is limited by the same kinds of processes that limit
the speed at which binary data can be sent between electronic transceivers (modems).
Noise introduced into the signal at both the transmitting and receiving ends or
in the transmission path connecting the two, degrades the ability of the receiver
(electronic and human) to discern between a "1" and a "0." It can take the form
of electrical or audio interference and distortion. Phase noise in the electronic
realm is sort of the equivalent of an irregular sending human hand that cannot maintain
equal dwell times for dits and dahs, thus making the recognition...
 Why Phase Stability Matters During RF/Microwave
Testing. When engineers evaluate RF test cables, specifications such as insertion
loss, VSWR, shielding effectiveness, and connector type typically receive the most
attention. Yet for many Vector Network Analyzer (VNA) applications, one characteristic
can have a greater impact on measurement accuracy than all of these combined: phase
stability. Phase stability refers to a cable assembly's ability to maintain a consistent
electrical phase relationship when subjected to movement, flexing, temperature changes,
or repeated...
 Magnetic amplifiers (aka "mag amps") use
a property of saturated core inductors (saturable reactors) to obtain signal amplification
via a transformer-type plus diode-assisted voltage multiplication.
Magnetic amplifiers were preferred over vacuum tube amplifiers
in some circuits because they do not require a high bias voltage, are generally
smaller in size, are quite robust and are practically immune to microphonics. Their
biggest limitation is bandwidth. The high number of turns in the core provides a
lot of interwinding capacitance so the self-resonant frequency is in the low megahertz
range. Additionally, the need for the magnetic amplifier reactor to operate in a
saturated condition further...
 Anritsu has been a global provider of innovative
communications test and measurement solutions for more than 120 years. Anritsu manufactures
a full line of innovative components and accessories for
RF and Microwave Test and Measurement
Equipment including attenuators & terminations; coaxial cables, connectors &
adapters; o-scopes; power meters & sensors; signal generators; antenna, signal,
spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth &
WLAN testers; PIM testers; amplifiers; power dividers; antennas. "We've Got You
Covered."
 The National Company, of Malden, Massachusetts,
which made this
cesium-based Atomichron in the mid-to-late 1950s, began life as
a toy manufacturer. It had an output frequency at the nominal resonance frequency
of cesium - 9192.631830 MHz - and was accurate to better than a second in 600
years. The unit was 7 feet tall and weighed 500 pounds. Modern cesium standards
are more stable and are portable. As of January 2013, the NIST-F1 cesium fountain
primary frequency standard is accurate to within one second every 100 million years!
That's a tad better than the Atomichron, non...
 This Bell Telephone Laboratories (aka Bell
Labs) advertisement appearing on the inside back cover of the 1958 issue of
Radio & TV News magazine celebrated the 10th anniversary of their
announcement of the world's first
point contact transfer resistance (transresistance) semiconductor
device - aka the transistor. John Bardeen, William Shockley and Walter Brattain
recorded the monumental event in a lab notebook on December 23, 1947 - a nice Christmas
present for the world! The trio's invention was not like the robust bipolar
transistors used today, or even ten years later in 1958. Rather than employing point-contact
"cat's whisker" metallic probes for making the emitter and collector...
 For many years, I have been scanning and
posting schematics & parts lists like this one that appeared in radio and electronics
magazines in the middle of the last century. Most use vacuum tubes. This
General Electric Model 280 Farm Radio "Radio Data Sheet" was in
the May 1947 issue of Radio-Craft magazine. The Radio Museum website has
more information on the GE Model 280 Farm Radio. Farm radios were designed to work
on storage batteries since until the Rural Electrification Act of 1936 was put into
effect, most rural properties had no commercial AC electric power service. 11 years
later, work was in progress to light up the entire country, but many locations had
to wait while resources...
 Here are a couple new-old
tech-themed comics from vintage Popular Electronics magazines.
Both have a Ham radio theme, so maybe you need to have been there to appreciate
the scenario... or maybe not. It is possible that the presence of clothes pins on
twin lead or ladder line could de-tune the line, and could crush the internal dielectric
of a coaxial line. There is no metal on boxer shorts, but maybe the clothes pins
are the type with a metal spring. For the other comic, you just need to know what
••• --- ••• is to get it. Enjoy...
 Question: If a fuse is rated at 3 amps,
at what value of current should it "blow?" Answer: Not at 3 amps. As this
Littelfuse company advertisement from a 1954 issue of Radio & Television
News magazine informs us, fuse ratings do not indicate the current value at
which a fuse opens to protect a circuits, but rather the maximum current level at
which it will NOT blow (open circuit). The same goes for circuit breakers. Various
types of fuses are available to handle certain types of applications. For instance,
a highly capacitive load will according to the well-known equation iC(t) = C * dv/dt
could draw a very large amount of initial (inrush) current if there is not enough
series resistance to limit it to prevent...
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Loading history...
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.
 Inductor-capacitor (LC) series and parallel combinations
comprised the first lumped element electrical filters for frequency discrimination. Below
a few MHz, with a little judicial placement of components and treatment of lead lengths,
building a successful
LC filter is not hard, and the measured response physical result looks very much
like the predicted response - provided the circuit model is sufficiently accurate. Above
50 MHz or so, very careful attention must be paid to parasitic elements (inter-turn
capacitance, lead inductance, cross-coupling) to get a good response. The advent of surface
mount components has made higher frequency LC filter...
 I tried to find some information on "direct-impedance
amplification," but alas none could be located. At first, I suspected that it being
in the April edition of Radio-Craft might have meant it was a ruse on readers,
especially since author L. Mitchell Barcus focused on the nearly sub-audible portion
of the sound spectrum down to around 16 Hz. Careful reading of the article reveals,
however, that his pièce de résistance was designing the circuit with a minimum of biasing
resistors, capacitors, and inductors that might otherwise attenuate low frequencies.
Success was in the form of direct coupling of stages sans Rs, Ls, and Cs. I'm guessing
the...
 By now, most people involved with spread spectrum
communications are (or should be) aware that Hollywood starlet
Hedy Lamarr is credited
for being the first to suggest a frequency hopping scheme for secure communications.
If you do a Google search on Hedy Lamarr and spread spectrum, you see that except for
a few mentions on tech websites, it has only been in the news since the end of the last
decade. Scientific American magazine ran an article titled, "Hedy Lamarr: Not
Just a Pretty Face," in 2008. Google honored her in 2015 with a Doodle on their homepage.
"The most beautiful woman in the world," with the assistance of her co-inventor-composer
George Antheil...
 This is Part 2 of a 3-part series of articles on
atomic radiation that appeared in Electronics World magazine in 1969. The
first part, which dealt with various types of radiation and how they interacted with
matter, was posted a week or so ago. For instance ionizing versus nonionizing radiation,
where the former can cause cancer, the latter just burns you. This installment discuses
methods and equipment for detecting and measuring radiation levels. Ionizing radiation
detectors rely on having massive particles impinge on gas, solid, or liquid media and
causing a reaction that is visible or measurable by electronic means. Nowadays there
are highly...
 This quiz tests your awareness of the many
mergers
and acquisitions that occurred in the RF, microwave, and analog electronics industries
during 2017. Mr. Raghav Kapur, of the everythingRF website, compiled a good list
of events with a short description of the transactions, so I used it to generate this
10-question quiz. It was made using Google Docs. Winners receive a free subscription
to the RF Cafe website for a full month. Good luck...
 At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's (1/15 - 1/19)
"Tech Industry Headlines" column on the RF Cafe homepage (see
the Headline Archives page for help). For the sake of all the avid cruciverbalists
amongst us, each week I create a new technology-themed crossword puzzle using only words
from my custom-created related to engineering, science, mathematics, chemistry, physics,
astronomy, etc. Enjoy!...
In 2010, I posted a short piece about where to
look on the Web to learn what upper management, board members, and large investors were
doing with
insider company stock trades. At the time, the MSN Money website had a tool where
you could enter a company's stock symbol and get a readout of who was buying and - more
often than not - selling stock. That web page is gone, but I found the same information
on InsiderCow.com. The dollar amounts are truly staggering to people like you (likely)
and me (definitely). Numbers reported are sale values, not profit to the stock holder.
Many of the stocks were issued as either grants or options, but even outright purchased
stocks are included as well. Regardless, prepare to have your jaw drop if you have never
seen this type of data before. Some of the more familiar technology companies have been
selected for examples...
 With as inexpensive and readily available as prefabricated
test lead holders are nowadays, there is not a lot of motivation to make your own.
Such was not necessarily the case in 1959 when this DIY article appeared in Electronics
World magazine. Still, if you have some spare sheet metal laying around and a bandsaw
to cut it, you can save a couple bucks (or euros, yen, rubles, etc.) by making one or
more yourself. All of my test leads are draped over nails driven into my wooden test
bench, which can create a nasty snarl. Maybe I'll whip up one of these for myself...
 Audio distortion is most often expressed as total
harmonic distortion (THD) as opposed to
intermodulation distortion (IMD). As the name suggests, THD is a measure of harmonic
power content relative to the fundamental frequency (a single tone) from which harmonics
are created. IMD on the other hand, is generated from the nonlinear mixing of two or
more tones, with the products being non-harmonically related to the original tones. The
author's discussion of audio frequency IMD applies equally to radio frequency IMD. Intentionally
generated harmonic components can enhance sound quality due to being consonant, whereas
IM products create dissonant tones not directly related to the originals...
 Hidden away on page 134 of a 1959 issue of
Electronics World, at the end of a Mac's Service Shop-like electronics
shop docudrama (Another Day in the Shop) is this handy tip on how to fabricate
a make-shift
thermal wire stripper from a soldering gun or a soldering iron. The beauty of
thermal strippers over mechanical strippers is that they do not nick the underlying metal
wire. Heated elements melt the insulation and then a blunt edge is used to slide the
insulation off the end of the wire. Another advantage is that you can strip a wide range
of wire gauges and insulation types without needing to adjust the jaws or change to a
different hole location - although a proper temperature setting is required to avoid
a gloppy, stringy mess...
 This 1970s-era Mac's Service Shop story made me
think about all the
cellphones today being dunked in toilets, swimming pools, lakes, and washing machines.
Of course back in Mac''s day not everyone was walking around with an electronic device
tucked into his or her pocket waiting for its absentminded owner to bend over or drop
his/her drawers. At the time, far more wallets made the dive than transistor radios.
I won't bother linking to any articles about how to best dry your dunked phone because
there are hundreds - nay, thousands - of them out there. They contradict each other about
which absorbent materials to use...
 This letter to the editor column from a 1969 issue
of Electronics World got my attention because of the submission by reader Walter T.
Stevenson. He mentions having discovered that semiconductors, in his case a transistor,
could have their
junction conductance modulated by ambient light sources, in his case a fluorescent
light. Evidently some of the early transistors were shipped on a substrate where the
die was potted with a translucent epoxy compound that permitted some light penetration.
At least one manufacturer switched to an opaque compound as a result of Mr. Stevenson's
report. I remember the first I experienced the phenomenon was as a technician working...
 At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's (1/22 - 1/26)
"Tech Industry Headlines" column on the RF Cafe homepage (see the Headline Archives page
for help). For the sake of all the avid cruciverbalists amongst us, each week I create
a new technology-themed crossword puzzle using only words from my custom-created related
to engineering, science, mathematics, chemistry, physics, astronomy, etc. Enjoy...
 Satellite evolution occurred at a rapid pace once
Sputnik and Echo were successfully launched in the late 1950s. Sputnik was a simple beacon
transmitter whose signal was used to measure orbital and atmospheric properties and their
effects on radio signals. Oh, and also to announce to the world that the USSR had accomplished
the world's first satellite mission - I'd brag, too. Explorer 1, the first
U.S. satellite, launched the following year, measured and broadcast Van Allen Radiation
Belt data. This Electronics World article appeared about a decade into the satellite
aspect of the "Space Race." By then...
 Dolby noise reduction is not really directly applicable
to the RF Cafe theme, but I included this article for two reasons. First, a lot of people
are familiar with the Dolby system and do not know its history or technical details.
Second, the general subject of noise reduction and dynamic range, avoidance, mitigation,
etc., is of interest even if the methods of dealing with audio noise is different from
radio signal noise. Dolby's companding (compressing-expanding) circuitry was an adaptation
of analog video noise reduction used in television. Interestingly, a lot of people evidently
were skeptical about... |
