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![To Be, Or Not to Be [a Metal] - Do Astrophysicists Know the Difference?: Kirt's Cogitations™ #374 - RF Cafe](miscellany/homepage-archive/2026/images/big-bang-universe-creation-kirt-blattenberger-hp.gif) As a
multi-decade-long amateur astronomer, I have read countless articles written by
astronomers who refer to all elements heavier than helium (#2 on the
periodic table of the elements) as "metals." Ostensibly, the origin stems from
early detection of heavy elements in stars, based on heliographic spectrum
investigations, where iron - being the most abundant stable byproduct of
supernova explosions - was most readily observed. I wondered if the "metals"
nomenclature came from the next heaviest element, lithium (#3 in the periodic
table), being a metal, thereby laying the foundation. Not so, claims AI, since
lithium is very rare overall in the universe, and not readily observed. For
clarity, I also procured the scientific distinction...
 I usually learn something new with each episode
of Mac's Radio Service Shop, but not necessarily related to electronics. Such is
the case this time where after Mac gives Barney a quick lesson in how to determine
a transformer's winding turns ratio when needing to create an impedance match circuit.
He then, while discussing whether "free" repair estimates are truly free or of any
real value at all, he uses the phrase "a horse on you." Maybe it is because I don't frequent bars that
I had never heard that, but after a little research I now know it refers to a bar
dice game called "'Horse." "A horse on you" is when you lose the final round of
a 2-out-of-3 challenge. "A horse apiece" is when you and your opponent each win
one round in a 2-out-of-3...
 "Data centers for AI are turning the world
of power generation on its head. There isn't enough power capacity on the grid to
even come close to how much energy is needed for the number being built. And traditional
transmission and distribution networks aren't efficient enough to take full advantage
of all the power available. According to the U.S. Energy Information Administration,
annual transmission and distribution losses average about 5%. The rate is much higher
in some other parts of the world. Hence, hyperscalers such as Amazon Web Services,
Google Cloud and Microsoft Azure are investigating every avenue to gain more power
and raise efficiency. The potential virtues of
high-temperature
superconductors..."
 Consumer grade
thermoelectric coolers have been around for so long now that most
people probably assume there is nothing wondrous about the discovery that makes
them possible. I still marvel at the process that allows the application of a current
through physical junction of two dissimilar metals (certain
types) to produce a cooling effect rather than the I2R heating normally associated
with conductors. This article from a scientist at Westinghouse Electric's research
laboratories provides a nice introduction to the subject of thermoelectricity from
both electric current generation based on the application of heat to a dissimilar
metals junction, and the aforementioned cooling effect possible from passing a current...
 FM radio has been in the news fairly frequently
in the last couple years as phone manufacturers and the
National Association of Broadcasters lobby the FCC and politicians
to mandate the inclusion of FM radio capability into every phone manufactured. In
a ploy to exploit the gullibility and egos of said bureaucrats and pols, their primary
argument that FM radio is a "first informer in times of crisis," assuming of course
that people will miss news of "the big one" when and if it occurs. To my knowledge,
successful reception of FM radio on a cellphone requires the listener wear a set
of wired ear buds since the wire from the phone to the ear buds functions as the
antenna. What percentage of cellphone users would bother to carry a set of ear buds?
I, of course, am a huge proponent of...
 Arthur Brach created many
crossword puzzles for Popular Electronics magazine in the 1950s and
1960s. Unlike the hundreds of RF Cafe Crossword Puzzles I designed over more than
two decades, the PE puzzles usually have a few words that are not specifically related
to electronics and/or technology. Still, they are a good source of a brief break
from the day's business. You will need to print out this crossword puzzle to work
it, since it is not interactive. Have fun.
 "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...
 Yowza, yowza, yowza
(The Jazz Singer),
QentComm's stock will be rising soon! "Quantum technology is already alive and
well in telecom networks, and although security is the top-of-mind use case, telcos
are also looking at quantum to make networks more resilient and transmit information
more quickly. Comcast announced this week it completed a trial with AMD and Classiq
that leveraged quantum software to find independent backup paths for network sites.
Elsewhere, Deutsche Telekom and Qunnect successfully demonstrated
quantum teleportation over an existing fiber network in Berlin..."
 The persona of Scott Adams' "Dilbert" is
described exactly in the opening sentence of this article in a 1930 edition of
Radio-Craft magazine. It is amazing - if not frustrating - to realize how
long the perception of science-minded people being introverts has been around. Dilbert's
"pointy-haired-boss" is nailed in the second sentence.
Georg von Arco is celebrated here as a major contributor to the
advancement of early radio, particularly wireless telegraphy equipment development.
Interestingly, as brought to my attention by Melanie as she did the text clean-up
after OCRing the magazine page, von Arco worked at the Sayville radio transmission
station on Long Island, New York, where the Telefunken Company's Dr. K.G. Frank
was arrested and interred for the duration of the World War I for sending out
"unneutral messages...
 Lots of Hams still use this tried-and-true
system for
tuning antennas for efficient operation on a variety of bands.
There are plenty of multi-band designs that rely on traps to reactively isolate
portions of the antenna that properly resonate at the desired frequency, but there
is usually a price to be paid in VSWR. Poor VSWR; i.e., higher mismatch loss, can
be overcome with higher transmitter output power, but the real sacrifice for poor
matching is loss of receiving range. The utter simplicity of using an insulated
cord to vary the physical length of the antenna element(s) for tuning is hard to
beat. It could be impractical on a setup where access to the antenna mount is difficult,
but my guess is most people can make good use of it...
 In this 1958 Popular Science magazine
article titled "Russian
Proposes Global TV," Soviet engineer V. Petrov proposed a global TV relay using
three geosynchronous satellites at 35,800 km altitude, launched 120° apart from
the equator at ~6,000 mph to match Earth's 24-hour rotation. Fixed over sites like
the USSR, China, and USA, they would relay signals - uplink on meter waves, downlink
on microwaves - via inter-satellite links, enabling worldwide broadcasts beyond
line-of-sight limits with directional antennas mitigating solar interference. Each
would require 10-kW antenna power, potentially reduced via pulsed transmission (note
digital waveforms in the drawing). This closely mirrored Arthur C. Clarke's 1945
Wireless World article "Extra-Terrestrial Relays," which...
 Frequency crowding has evidently been an
issue since the early days of radio according to this 1930 article in Radio-Craft
magazine. The situation was really bad in the earliest times when unfiltered spark
type transmitters were the norm. Those pioneers could be credited, I suppose, with
being the first users of wideband communications, but it was not because they chose
to do so. Here author Clyde Fitch discusses the debate over whether there really
were such things as sidebands from modulation and makes an argument for their existence
based on analysis of various types of modulation. In particular, he predicts the
coming popularity of single sideband receivers with crystal-filtered channels, and
the need for matching SSB transmitters with... wait for it... carrier and sideband
suppression...
 "A new transceiver developed by electrical
engineers at the University of California, Irvine boosts radio frequencies into
140-gigahertz territory, unlocking data speeds that rival those of physical
fiber-optic cables and laying the groundwork for a transition to 6G and FutureG
data transmission protocols. To create the transceiver, researchers in UC Irvine's
Samueli School of Engineering devised a unique architecture that blends digital
and analog processing. The result is a silicon chip system, comprising both a transmitter
and a receiver, that's capable of processing digital signals significantly faster..."
 Somehow, after being in the RF business
for four decades, I have to admit to not being familiar with the term
"acceptance angle" for antennas. That is after having read scores
of articles on antennas. Maybe I did and just don't remember - embarrassing. Acceptance
angle is mentioned and explained in this article during the description of rhombic
antenna characteristics versus dipoles and multi-element designs. Although the author
focuses on television installations, information provided on signal reflections,
shadowing, ghosting, multipath, etc., is applicable to radio as well...
 Electrolytic capacitors have long been the
components that provide the highest capacitance density factor, that is, they have
the highest capacitance value for a given volume of space occupied. Anyone familiar
with electrolytic capacitors is aware of the polarization indicated on the package
(a marking or unique physical feature), indicating that there is required direction
for hookup; in fact, a backwards connection can lead to an explosive failure. While
physical construction of electrolytic capacitors have evolved over the decades since
this article was published, the fundamental operation has not. It is interesting
to note the reference to capacitors as "condensers," a name still commonly used
with internal combustion engine ignition systems and with some AC motors that use
them at turn-on for providing a starting coil phase shift...
 This 1959 Popular Science magazine
reprint of a 1925 Radio News magazine article focused is on visionary physicist
Robert H. Goddard's proposed Moon Rocket as a means to test
whether radio waves can traverse interstellar space, potentially enabling communication
with other planets. Amid recent radio achievements, including mysterious signals
during Mars' approach and solar disturbances recorded on Earth, the piece challenges
Oliver Heaviside's theory that radio waves are confined by Earth's atmosphere. Goddard's
innovative rocket, propelled by successive explosive charges to escape gravity and
reach the Moon, would carry a compact radio transmitter in its nose cone, broadcasting
signals throughout its flight. Astronomers would track...
 This week's
crossword puzzle, as with all RF Cafe puzzles, uses only words
pertaining to engineering, science, mathematics, mechanics, chemistry, astronomy,
etc. You will never find a reference to some obscure geological feature or city,
or be asked to recall the name of some numbnut movie star or fashion designer. You
will, however, need to know the name of a famous RF filter design software author.
Enjoy...
 "Broadband achromatic wavefront control
plays a central role in next-generation photonic technologies, including full-color
imaging and multi-spectral sensing. A research team led by Professor Yijun Feng
and Professor Ke Chen at Nanjing University has now reported a significant advance
in this field in PhotoniX. The researchers introduced a hybrid-phase cooperative
dispersion-engineering approach that combines Aharonov-Anandan (AA) and Pancharatnam–Berry
(PB) geometric phases within a single-layer metasurface. This strategy enables
independent achromatic control of wavefronts for two different light spin states..."
 As with the article in this month's issue
of Radio-Craft magazine (December 1937), the reference to a 200th anniversary
is understated by 88 years for 2025.
Luigi Galvani was sort of the Benjamin Franklin of biology in
that just as Franklin demonstrated that lightning was a form of electricity, Galvani
showed that signals sent from the brains to the appendages of animals were electrical
in nature. In my high school days in the 1970s, we duplicated his experiment by
making deceased frogs' legs twitch when motivated by a D cell. Today, such an exercise
would likely be met with demonstrations by animal rights people (whose lives, BTW,
have probably in some way been improved as a result of previous such experiments).
But, I digress. Mr. Galvani's name is...
 Superheterodyne receivers were originally
the sole domain of the Radio Corporation of America (RCA), which owned the patents
and refused to license them until around 1930. Hugo Gernsback, a contemporary editor
of the era, provides a little insight into the superregenerative receiver circuits
superheterodyne was about to replace, and why it was an important improvement in
technology. Sidebar: The question often
arises regarding the difference between a "heterodyne" circuit and a "superheterodyne"
circuit. The most popular answer that "super" refers to the IF being located above
the range of human hearing, which peaks at about 15 kHz. Doing so assured that
any IF leakage into the audio circuits would not be discernable by a radio...
 Carl and Jerry stories are usually a good
mixture of teenage curiosity, adventure, and electronics technology, but this "Out
of the Depths" episode is a bit too far-fetched. The first ninety percent of
this 1957 Popular Electronics magazine tale fulfills expectations, with
the boys applying their shared interest in technology while attempting to learn
and apply the technique of luring elusive fish from their safe dwelling places and
onto the ends of their hooks. A car battery, DC-to-AC inverter, tape recorder, and
high-gain microphone are the basis for the scheme. Things were going well, and I
expected the normal hard-fought victory with big, fat bass in their creels - and
then something only slightly more believable than finding a crashed alien spaceship...
 RCA, the
Radio Corporation of America was not merely a manufacturer of
radio, television, and phonograph equipment for home entertainment. The company
also made vacuum tubes for all sots of electronic equipment, and produced a weekly
radio broadcast called "Magic Key" on the NBC Blue Network. Sticking to their communications
roots, RCA today markets televisions, microwave ovens, Android-based tablet computers,
DVD / Blu Ray drives, telephones, 2-way radios, radios, clocks, antennas, and many
other devices - with no tubes in sight, not even in their TV displays...
 "Scientists at the University of New Hampshire
are using artificial intelligence to dramatically speed up the search for
new magnetic materials. Their approach has produced a searchable database containing
67,573 magnetic materials, including 25 previously unknown compounds that retain
their magnetism at high temperatures, a key requirement for many real-world applications.
'By accelerating the discovery of sustainable magnetic materials, we can reduce
dependence on rare earth elements, lower the cost of electric vehicles and renewable
energy systems, and strengthen the U.S. manufacturing base,' said Suman Itani, lead
author of the study..."
 Breaking News!
Espresso
Engineering Workbook™ v3.2.2026 has just been released. This makes the 49th
worksheet added. It calculates magnitude, phase, and group delay for Butterworth
and Chebyshev lowpass, highpass, bandpass, and bandstop filters. Outside of the
kilobuck simulators, finding a calculator for phase and group delay is extremely
difficult - believe me, I've searched extensively for years. Espresso Engineering
Workbook™ can be downloaded free of charge. All you need is Excel™ v2007 or newer.
It is provided compliments of my advertisers. Contact me if you would like your
company added to the next release.
 Disneyland opened its gates in Anaheim,
California on July 17, 1955. It was billed as the most high-tech theme park in the
world, with a "wow" factor on par with the World's Fair extravaganzas. One of its
much-ballyhooed features was the "realistic" jungle safari tour with life-like animal
automatons and authentic 3-D jungle sounds. This article, published less than a
year after opening day, highlights some of the equipment and methods used by artists
and engineers to achieve the effects...
|
 • Revisiting
the
1996 Telecommunications Act
• China's
BeiDou Satellite (their GPS) Does Emergency Messaging
• How & When Will
Memory Chip Shortage End?
• At Age 25, Wikipedia
Refuses to Evolve
• Amazon Leo Asks FCC for
Satellite Launch Extension
• FCC Gives
Amazon OK for 4,500 More Satellites
 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.
 I'm not too proud or vain to admit that
until I saw this advertisement in a 1946 issue of Radio News magazine,
I did not know (or don't remember knowing) that "Amphenol" is a compact form of
the
American Phenolic Corporation. Phenol formaldehyde is the technical name for
phenolic. Bakelite, the trade name for polyoxybenzylmethylenglycolanhydride,
is probably the most familiar form of phenolic since it was used in many types of
electronics for both enclosures and internal component boards and the components
mounted on them, connectors, and more. Modern plastics, fiberglass, and resin compounds
have replaced most or all phenolic components. This particular promotion is specifically
directed toward amateur radio operators (aka Hams), who composed a fairly large
fraction of the magazine's audience. BTW, Amphenol is one of the diminishingly small
number of American companies still around going by their original name. Even more
rare is that it appears to still be a U.S.-based concern...
 "One of the least orderly and most poorly executed
of NASA projects," was the description given to the
Surveyor program whose goal was to land on the moon and send back images,
both still and motion (in preparation for a manned landing). That, from a
congressional sub-committee. Yes, the very same Congress that famously cannot
balance its own budget or create successful programs of its own. It is a classic
case of "The pot calling the kettle black." NASA was and always has been at the
bleeding edge of new technology and as such lives in uncharted territory.
Unexpected pitfalls lurk everywhere - a minefield of "gotchas." Not that every
organization can't benefit from external oversight to prevent "blinders-on"
engineering and management teams from straying too far off the defined path, but
having the notoriously pompous and buffoonish bureaucrats...
 Most people who have been in the electronics
world for a while know that neon light bulbs* used to be commonly employed as a
"pert-near" voltage regulator reference of between 55 and 65 volts, depending on
the type. The familiar NE-2 has a turn-on voltage of 65 Vac (90 Vdc),
for instance, and the voltage across the terminals remains there with little change
regardless of the current through the bulb - a lot like a Zener diode. Neon bulbs
are also used as non-invasive RF power detectors. Most people probably do not know,
however, that incandescent bulbs also have properties that make them useful for
purposes other than just lighting up a dark space.
Incandescent light bulbs have been used successfully for voltage regulation
and RF power measurement. They have also been used as dummy loads for transmitters.
John Parchman details some of these uses...
 There aren't many people using
transistor substitution boxes these days because circuit simulator software
is readily available to reasonably predict which type will serve the intended purpose.
However, back in 1960 when this article appeared in Radio-Electronics maga
zine, substitution boxes for not just transistors, but also capacitors, resistors,
and sometimes inductors were used quite often when prototyping and/or troubleshooting
circuits. I used resistor and capacitor substitution boxes all the time in the early
and mid 1980's while working as an electronics technician at Westinghouse Oceanic
Division, in Annapolis, Maryland. That was my first place of employment after separating
from the USAF. Prior to moving into the engineering lab, I built electronics assemblies
for U.S. Navy sonars used on torpedoes, ship hulls, and towed vehicles, including
printed circuit assemblies, cable harnesses, chassis assemblies, and piezoelectric
transducers. Occasionally, I was tasked to build component substitution boxes for
the engineering lab and the test equipment repair / calibration (metrology) group.
Little did I know at the time that in the near future I would be using some of the
equipment I built...
 According
to a 2001 paper published by the National Institute of Standards and Technology
(NIST, formerly National Bureau of Standards, NBS), "The end of the era of quartz
frequency standards began in 1949 with the development at NBS of the world's first
atomic frequency standard based on an ammonia absorption line at 23.87 GHz."
Further, "The Bureau supported work on both technologies for the next decade, but
the rapid advances in the accuracy of atomic frequency standards could not be matched
by
quartz devices, and the work on quartz frequency standards was
stopped in 1959." This article from a 1957 edition of Popular Electronics
claims that the "master of all master-clocks" resided at the U.S. Naval Observatory
at the time - not quite accurate from what my research indicates...
 Anyone visiting RF Cafe (other than by accident)
almost certainly knows of
Drs. Bardeen, Brattain and Shockley fame for their transistor invention while
jointly working at the Bell Telephone Laboratories. The trio shared The Nobel Prize
in Physics in 1956. Bell was so proud of their employees' efforts that they ran
full page advertisements to boast of the accomplishment. This one appeared in the
February 1957 edition of Radio & Television News. Alas, Ma Bell's moment
of glory was a bit diminished by needing to add a footnote admitting that Drs. Bardeen
and Shockley no longer work there. Note that while the ad says the transistor was
announced in 1948, the first demonstration to Bell managers was in December of 1947...
 According to authors Neal Jensen and Alexander
Burawa,
magnetic reed switches were developed as recently as 1940 at the Bell
Telephone Laboratories to replace the expensive and power-hungry traditional
solenoid-based relays. Development cost was reportedly $100 million ($750M in
2018 dollars). I would have guessed reed switches were invented half a century
earlier, given how fundamental their concept and construction is. Maybe there
was no perceived urgency back when power efficiency was not such a big concern
given the wattage used by vacuum tube circuits that often employed the relays.
As in increasing number of homes and businesses had telephones installed and
party lines (shared by two or more users) gave way to private lines, the
physical...
 Comics in modern magazines are a rather
rare phenomenon for some reason, but they were fairly regular features up until
a couple decades ago. This set of
comics from the July 1963 edition of Popular Electronics deals with
high fidelity (Hi-Fi) stereo equipment, which was considered somewhat exotic and
high-end for many people's budgets in the day. Inexplicably (not), that is about
the time that increases in hearing losses among younger people were first being
noticed in audiograms.
 E. Aisberg wrote a series of columns
for Radio-Electronics magazine in the middle 1950s titled "Television...
It's a Cinch," informing the reading public about television in general and
the newly emerging color TV more specifically. He chose to use a unique dialog format
where two people were in a back-and-forth discussion about the technology. This
July installment is the first half of the seventeenth conversation. Antennas, tuned
circuits, component reliability, transmission lines, installation, and many other
aspects of successful television viewing are covered. The series began with the
February 1953 issue, and ran through October 1955. I will post the others as time
permits...
 For someone interested in getting into aviation
electronics in 1948, this career deal offered by
American Airlines was an exceptional opportunity. If chosen for the program,
an intense six-month training regimen would prepare the student for a career in
radio, radar, navigational aids, and other systems. All living costs would be covered,
along with a $120 per month stipend which, according to the Bureau of Labor Statistics'
Inflation Calculator, is the equivalent of about $1,450 ($17.4k/yr) in March of
2022. Although I don't have the numbers, my guess is that this was a much better
deal than the military was offering at the time, especially considering no conscription
was involved. American Airlines began service in 1936, and is one of the few carriers
of the era still in operation today...
 Ask and ye shall receive... at least sometimes.
I posted a request for an article by science fiction writer Arthur C. Clarke, of
2001: A Space Odyssey fame, describing a
geostationary satellite system that was published in the October
1945 edition of Wireless World magazine. Thanks to RF Cafe visitor Terry
W., from the great state of Oklahoma, it is now available for everyone to enjoy.
Clarke was not just a sci-fi writer, but also an educated visionary and card-carrying
member of the British Interplanetary Society, who proposed many technological solutions
to issues of his day. In this instance, the challenge was developing an efficient
means to distribute TV signals across Europe and the world. Clarke's calculations
for the necessary number of repeater towers proved that concept impractical, so
he proposed using modified surplus German V2 rockets to launch Earth-orbiting "artificial
satellites," powered...
 Since 2000, I have been creating 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...
 If the
electronics-themed comic from page 35 of the February 1946 issue of Radio
News magazine was drawn today, you might think the face-diapered mother-in-law
was a Covid-19'er (although improperly worn). Then again, if that comic were published
today, the magazine and the artist would be cancelled on social media for daring
to poke fun at the lady. The page 48 comic reflected the love-hate relationship
the public had with electronic repair shops in the era. Peruse through the plethora
of comics as well as multiple stories in the vintage electronics industry magazines
here on RF cafe and you will find many examples of the same theme. Shop owners routinely
were accused of overcharging customers for labor and for needlessly replacing components
(and for charging for new parts when used or repaired parts were installed). In
truth, there was a lot of ripping-off of customers, but there was also a lot of
customers refusing to pay for honest repairs...
 The Federal Communications Commission (FCC)
claimed in 2013 to be receiving more than 30,000 applications per year for
commercial broadcasting licenses. That covers the gamut from AM and FM to television,
Low Power FM, Low Power TV, translators and booster stations, as well as some non-commercial
stations for educational purposes. Inexpensive, turnkey broadcast station equipment
make entry into the realm very affordable. Accordingly, there are many stations
vying for space in a very crowded section of the electromagnetic spectrum. Contrast
that to the year 1932 list of broadcasting station in the U.S. which was able to
fit onto a single page of the Radio News magazine - about 500 to 600 in number.
Interestingly, the wavelengths are expressed in meters, at a time when metric units
were rarely used in the U.S...
 Wirewound inductors
(as most are) can be mysterious entities even when you
are familiar with their many interdependent physical and electrical properties. Because
of interwinding capacitance and a sometimes (when a large number
of turns are involved) rather significant series resistance, the equivalent circuit
model gets quite complex - literally in a mathematical sense. If you have the luxury
of staying far away from the self-resonant frequency (SRF)
of the coil, your component will behave very much like an ideal inductor, that is, XL
= 2πfL. This
article delves into what causes inductors to...
 In part one of a two-part article, Popular
Electronics magazine presents some of the inner workings of what at the time was
a fledgling industry -
printed circuit board manufacturing. In 1956, when this piece appeared, a large
percentage of electronics assemblies were still being wired in a point-to-point
manner where resistors, capacitors, inductors, tubes, and cables were soldered directly
to terminals either on special blocks or on tube sockets. The process was heavily
labor intensive and prone to miswirings. High volume production was nearly impossible
prior to printed wiring boards (PWBs). Bell Telephone Labs was an early adopter
and driver of the technology. A good example of an early telephone PWB can be seen
in the 1970s vintage Snoopy telephone that I reconditioned a while back. Note the
rat's nest of wires going to the network terminal block...
 This is another Radio Service Data Sheet
that appeared in the March 1936 edition of Radio-Craft magazine. I post
this schematic and functional description of the Crosley Model 515 (Fiver) 5-Tube
2-Band Superhet radio manufacturers' publications for the benefit of hobbyists
and archivists who might be searching for such information either in a effort to
restore a radio to working condition, or to collect archival information. An extensive
list of similar radio service data sheets from many different electronics magazines
of the day is at the bottom of the page...
 Here are a few
tech-themed comics from the April 1967 edition of Popular Electronics
magazine depicting the perception of techies during the era. I took the liberty
of colorizing them. As mentioned before, stereo equipment was a big deal in the
era, back before most people listened to music through ear buds attached to smartphones.
When in the USAF in the early 1980s, a sure sign of hipness was to have 19" equipment
rack in your barracks room, stuffed full with a reel-to-reel tape deck, a high end
AM/FM receiver ("tuner," to the audiophile), power amplifier that could deliver
at least 200 W per channel, a dual cassette deck, turntable (referring to it
as a "phonograph" revealed your squareness). Of course no self-respecting stereo
aficionado would be caught dead with an 8-track tape deck in the rack. Things really
haven't changed much when it comes to serious audiophiles, except now a CD/DVD player
will be included... |
