|
 Take a break from workaday drudgery by trying
your hand at this week's
Amateur Radio crossword puzzle. Every word in the RF Cafe crossword
puzzle contains the usual collection of science, math, and engineering terms, and
also includes special words related to Amateur Radio (clues labeled with asterisk
*). There are no generic backfill words like many other puzzles give you, so you'll
never see a clue asking for the name of a movie star or a mountain on the Russia-China
border. You might, however, find someone or something in the otherwise excluded
list directly related to this puzzle's technology theme, such as Hedy Lamarr or
the Bikini Atoll, respectively. Enjoy.
 "Advanced threats lead to open architecture
approaches and new
analysis of electronic countermeasures. Over the past decade, preeminent countries
involved in major military conflicts mainly focused on asymmetrical warfare - surprise
attacks by small groups armed with modern, high-tech weaponry. During that same
period, however, near-peer adversaries began attaining impressive electronic warfare
(EW) capabilities. As a result, a plethora of new, dynamic threats flooded the EW
spectrum, pushing threat detection and analysis to keep pace. Large military forces
must now engage in ongoing..."
 Here are a couple more electronics-themed
comics from Electronics World magazine, good for winding down the week.
They appeared in the January 1963 issue. The page 86 comic reminds me of the professor
I had for solid state circuit design. He was supposedly the first person to successfully
use gallium arsenide (GaAs) as a semiconductor, although he also did pioneering
work with silicon. Anyway, Prof. Anderson would say he takes at least one "business"
trip each year to Portugal in order to search for higher quality raw semiconductor
material in sand on the beaches. He spoke Portuguese, BTW. The page 89 comic is
reminiscent of the pre-GPS days of navigation. Raise you hand if you ever drove
around utterly lost while looking for an off-the-beaten-path location...
 In the mid 1930s, hand-assembled products
were by far the rule rather than the exception for most products be they electronics,
furniture, appliances, automobiles, or toys. Many people lament - even curse - the
advent of machine automation in production, but the fact is for the vast majority
of things the consistency and quality of the finished component is typically much
greater. Toiling at the same task, in the same location, day after day, gets unbearable
very quickly for someone like me who likes to accomplish a particular job and then
move on to something new - even if "new" is defined as the same type of endeavor
but with different materials. There are many people, thankfully...
 At Parvoo University, amid relentless November
rain, H-3 dormmates Carl and Jerry pursue H-2's prank: a stolen bronze trophy plaque
hurled into a half-mile muddy stretch of river. Cold, turbid waters bar preclude
dives for a search; non-magnetic bronze defies current-day metal detectors. Jerry
repurposes his cousin's boat depth-finder as an
enhanced sonar, exploiting echo signatures. A motor rotates a neon tube across
a depth-calibrated dial; at zero, contacts trigger a 200-kc ultrasonic pulse from
the transducer in transmit (speaker) mode, flashing initial glow. Bottom echo reflects
to transducer in receive (microphone) mode, amplifying...
 The announcement and public demonstration
of Senatore Guglielmo Marconi's "death ray" device was the coming true of some of the worst fears
of science fiction aficionados. Application of these newly created centimeter wave
"beams" could roast the flesh of man or beast when generated with great enough power.
The diminutive wavelength not only would heat liquids, but also provided a means
of detecting and measuring energy reflected off of "targets" such as aircraft and
boats. It applications were endless. Although not called so, one of the article's
diagrams looks to be an example of a bistatic radar system. The early magnetron
implementation is quite different...
 The Federal Communications Commission (FCC)
is looking for qualified applicants for
Field Agents in seven Enforcement
Bureau (EB) offices across the United States: Atlanta, GA; Boston, MA; Chicago,
IL; Dallas, TX; New Orleans, LA; New York, NY, and Portland, OR. Incumbents will
resolve Radio Frequency (RF) interference, educate users, and enforce regulations.
The GS levels for this position have been expanded to GS 7, opening the opportunity
for new college graduates. One year of work experience is not required for this
position. Closing date is March 2, 2026...
 If you are from a family of electronics
hobbyists and/or professionals, then there is a good chance your grandfather and
possibly even your father kept a handy-dandy list of common
circuit design formulas handy. Part 2 of the list appeared here in a 1930 issue
of Radio-Craft magazine. All the formulas on this page dealt primarily
with vacuum tubes, the schematics for which were presented in Part 1 of the series.
There are still lots of hobbyists who restore and/or modify vintage sets, so the
equations are still worth publishing. There was not an "app for that" back in those
days. Prior to a smartphone in every pocket, notes were pinned to a lab wall or
kept in a hand-written notebook...
 The name
Frank Conrad probably does not sound familiar to most people in
the electronics communications field today, but at one time he was the assistant
chief engineer to the Westinghouse Company. Back when voice radio (as opposed to
Morse code, aka CW) was being pioneered, Mr. Conrad was widely known for his efforts
in commissioning the country's first commercial broadcast installation - KDKA in
Pittsburgh, Pennsylvania. His arranging for live coverage of election night results
in 1920 is credited for launching a huge interest by consumers in purchasing radio
sets for their homes (Warren Harding beat James Cox that night, BTW). Toward the
end of his career, Conrad was active in helping develop...
 Copper Mountain Technologies develops innovative
and robust RF test and measurement solutions for engineers all over the world. Copper
Mountain's extensive line of unique form factor
Vector Network Analyzers
include an RF measurement module and a software application which runs on any Windows
PC, laptop or tablet, connecting to the measurement hardware via USB interface.
The result is a lower cost, faster, more effective test process that fits into the
modern workspace in lab, production, field and secure testing environments. 50 Ω
and 75 Ω models are available, along with a full line of precision calibration
and connector adaptors.
 Details of ancient Parthian
electrochemical batteries unearthed near Baghdad by archaeologist Wilhelm Konig,
dating over 2,000 years, was reported in this 1964 Popular Electronics
magazine article. Housed in earthenware jars sealed with asphaltum (bitumen), they
featured a copper cylinder soldered with 60/40 tin-lead alloy - identical to modern
electronics, prior to PB-free mandates - encasing a corroded iron rod for electrodes,
enabling electroplating of gold, silver, and antimony via electrolytes like copper
sulphate, ferrocyanides, or lye. GE engineer Willard F.M. Gray replicated them successfully
for Pittsfield's Berkshire Museum, using iron rods for series connections. More
cells surfaced in a Seleucia magician's hut and Berlin Museum...
 It seems most of the articles we see on
the subject of attenuator pads are based on signal reduction in terms of decibels
for units of power. Although it is a simple matter to convert power decibels to
voltage decibels, it would be more convenient if you are working with voltage to
have formulas and tables of values based on voltage ratios. This article does just
that. As a reminder, the decibel representation of a ratio is always 10 * log10 (x).
If you have a voltage ratio of V1/V2 = 0.5, then
10 * log10 (0.5) = -3.01 dB. If you have
a power ratio of P1/P2 = 0.5, then 10 * log10 (0.5) = -3.01 dB.
Does that mean that -3.01 dB of voltage attenuation is the same as 3.01 dB
of power attenuation...
 This might be a perfect application for
QuentComm. "Researchers led at the University
of Science and Technology of China (USTC), have achieved a major milestone in quantum
communication. For the first time, they demonstrated a key component required for
scalable quantum repeaters, which later allowed them to carry out device-independent
quantum key distribution (DI-QKD) across 100 kilometers. The results, published
in Nature and in Science, represent important progress toward building a functional
quantum internet. The work also reinforces China's position at the forefront of
quantum research and technology..."
 This Radio Service Data Sheet for the Clarion
"Replacement" Chassis, Model AC-160 A.V.C. Superhet is an example of the dozens
of similar schematic and alignment instruction sheets that have been posted on RF
Cafe over the years. Obtaining technical information on most things, even readily
available items, prior to the Internet era was often very difficult - if not impossible.
Service centers had what was need provided by manufacturers and distributors, but
if you wanted to find a part number or service data on a refrigerator, radio, lawn
mower, garage door opener...
 Remember the test patterns that used to
be broadcast by over-the-air broadcast stations that were used to align the electron
beam defection circuitry in CRT-based televisions? That pattern of squares, circles,
parallel and radial lines was generated by a special tube called a "Monoscope" on the transmitter end. Focus, 4:3 picture aspect ratio,
linearity, frequency response, and contrast and brightness were all tweaked to optimize
the pattern on the TV receiver circuitry. Of course not all sets were capable of
obtaining a perfect alignment due to inferior design and/or a scheme by the manufacturer
to provide a lower cost model with the tradeoff being a poorer picture - that it
the type of TV we always had in our household as...
 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."
 Dave Harbaugh created a great many electronics-themed
comics back in the 1960s for magazines like Popular Electronics, QST,
"73", and others. His "Hobnobbing
with Harbaugh" series usually depicted hobbyists and technicians in a state
of surprise and/or dismay over some event while in the act of pursuing his passion
(electronics, that is, not a woman). Although I have never run across any evidence
of it, I wonder how many of the scenarios are derived from personal experience.
Many do not have captions. I have to admit to being stumped at what he is trying
to convey in the comic where the guy is staring into the back of the TV while his
wife...
 Competition amongst countries and businesses
existed long before the advent of radio receivers. Here is an interesting story
which demonstrates how international politics and corporate policies has been part
of the electronics industry since its inception. In order to circumvent what were
considered to be outlandish patent licensing fees, Danish engineer Carl Arne Scheimann
Jensen developed a new "gridless" type of vacuum tube (aka valve) which was called
the "Renode." Rather than using a screen grid in the path between the
cathode and plate, the Renode employed two sets of beam concentrator and deflector
plates on either side of the electron beam's path to modulate the conduction. According
to measurements it provided a slight improvement in both linearity and selectivity...
 "Sixth-generation wireless networks, or
6G, are expected to achieve terabit-per-second speeds using terahertz frequencies.
However, to harness the terahertz spectrum, complicated device designs are typically
needed to establish multiple high-speed connections. Now research suggests that
advanced topological materials may ultimately help to achieve such links. The experimental
device the researchers have made, in fact, achieved 72 gigabits-per-second data
rates, and reached more than 75% of the three-dimensional space around it. Current
solutions typically achieve only one or two of these features at a time and often
rely on complex
antenna arrays or mechanical steering..."
 This week's
RF & Microwave Companies crossword puzzle includes the names
of all my current advertisers and a few others that will be familiar to many of
you. These kinds of puzzles take a particularly long time to create because of needing
to force words into certain positions. That leaves the software with fewer options
for fitting the other words. All the words in RF Cafe crossword puzzles are relevant
to engineering, science, mathematics, etc., stored in a hand-built (over more than
two decades) lexicon of thousands of terms and clues. Enjoy...
 Mystery stories were broadcast on radio
stations in the days before television - and for quite a while after TV was available
for that matter. Families gathered around the living room radio set in excited anticipation
of the next adventure of shows like "The Shadow," "Amos 'n' Andy," "Tales of the
Texas Rangers," "Dragnet," and "The Green Hornet." During that era, it was common
also for electronics magazines, which focused largely on radio communications, to
experiment with printed dramas that had a radio-centric theme. Here is the first
of a series tried by Radio-Craft magazine in the late 1930s. A couple decades
later the Carl & Jerry adventures were run in Popular Electronics,
but other than that I don't recall seeing a lot of these things...
 Diode characteristics and their applications
have not changed fundamentally since this article was published in 1952. Sure, the
die are smaller, power handling and frequency range has increased, package styles
are greatly expanded, and the cost per unit is way down, but if you are looking
for some basic diode information, you will find it here in this 4th installment
of a multi-part series in Radio & Television News magazine. Don't let
the vacuum tubes in schematics scare you off and think that it makes the story irrelevant
for today's circuits. For purposes of illustration substitute a transistor's collector
(or drain) for the tube's plate, a transistor's base (or gate) for the tube's screen
grid, and a transistor's emitter (or source) for the tube's...
 The term "drone"
these days for most invokes the image of a little plastic spider-looking thing with
propellers mounted at the ends of the arms - usually with a toothless bumpkin at
the controls. Those same people often think drones are relatively new devices. People
with a just a little more information automatically classify all radio control (R/C)
models, be they traditional fixed-wing aircraft or helicopters, as drones. Pilots
of the aforementioned models are even likely, per observers, to have all their teeth
and bathe regularly. I happen to be one of the latter type R/C modelers and while
I no longer possess all 32 teeth I had at birth, I do bathe regularly. Drones have
been around since World War I where they were used for target practice by ground-based
mark...
 "If you have dark eyes and blonde hair.
and are under 30, you're due for some easy squeezing. Milligan's Appliance Center,
84 Main Street, is giving every girl between 16 and 30 who has these striking features
a newly patented orange squeezer, to introduce the new item ... Note: Any traces
of recent peroxide rinse will disqualify applicants." That is advertising copy offered
as an example effective promotional material in a 1947 edition of
Radio News. My first reaction was to think how something
like that would never fly today, but then I wasn't so sure. It seems there must
be anti-discrimination laws in this "offend nobody" climate today...
 Imagine having a serviceman of any sort
arrive at your house, fix your problem, and present you with a bill of $6 - parts
included. He would walk away satisfied that he had done a good job and was well
compensated for the work considering the effort invested in training and qualification.
$6 in 1932, per the Bureau of Labor Statistics'
Inflation Calculator is worth $135.97 in 2015 money - that's a
cheap service call even in today's economy. Further, the $14 stated as a day's earnings
is $317.26 in 2025, which equates to 50 (work weeks/year) x 5 (days/week) x $243.86
(/day) = $79,315 (/year) - not too shabby. Just between you and me, that's more
than I'm currently making per year running RF Cafe...
|
 • ARRL
Student Coding Contest $25k Award
• Shielding
Electronics Supply Chain from Cyberthreats
• Fund Opens
Defence Contracts to UK Startups
• Global
Trade Holds Its Ground
• FCC
"Supercharge" Wi-Fi in 6 GHz Band
• Legacy
Memory (DDR2, 3, 4) in Demand but Scarce
 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.
 Do you remember back in the 1980s when adoption
of the IEEE-type logic schematic symbols* got a big push? It proposed a logical
approach (pun intended) to building any type of combinational logic or sequential
logic devices based on strict rules of construction. Curved lines are nowhere in
sight. Interestingly, the same type of schematic symbol "simplification" was proposed
in the 1940s. The motivation for removing curved lines was to prevent draftsmen
from needing to use a compass or special drawing template rather than using only
a straight edge. Vacuum tube outlines, light bulbs, inductors, etc., required more
time to pencil in. In 1944, this article entitled "Are
Radio Symbols Wrong?" appeared in Radio-Craft magazine...
 Right on time for the anniversary of
Pierre and Marie Curie's 1989 discovery of the radioactive element radium is
this article which appeared in a 1944 issue of Radio-Craft magazine. Editor Hugo
Gernsback comments on the recently released (1943) film entitled "Madame Curie*,"
starring Greer Garson as Marie Curie and Walter Pidgeon as Pierre, criticizing it
for not delving more deeply into the technical aspects of radium. Chief among the
objections was the omission of information about how radiation treatment had been
shown to cure some forms of cancer. Indeed, he cited his own experience with a "growth"
on his hand that was successfully treated at a "radium hospital" where the doctor
applied a bulb of radium to the tissue for a mere five minutes. It disappeared in
less than two weeks. Beyond that would be radium's usefulness in generating electricity,
creating wonderful visual effects created by its elemental decay using a spinthariscope...
 With such a good response to the posting
of articles from vintage QST magazines, I figured it would be worth investing
in some copies of other electronics-related magazines because people old and young
enjoy learning about the history of electronics.
Popular Electronics was published from October 1954 through April 1985.
I remember reading the magazine back in my USAF days (1978-1982). A couple batches
of Popular Electronics magazines came up for auction on eBay back in the middle
of 2011, and I managed to snag one set that included the December 1954 issue (Vol.
1, No. 3, which was the third edition ever printed). It also included some editions
from early 1955 and others stretched into the early 1960s. This is the first installment.
Popular Electronics was a hobbyist's magazine, and was chock full articles
on small electronics projects, Ham radio, radio-controlled aircraft equipment, audio
amplifiers, model train control, basic electronics lessons, and useful charts and
tables of data...
 Here is a back-to-the-basics
treatise on AC and DC, plus an introduction to radio frequencies (RF). The author,
Herb. S. Brier, is a licensed Ham who presents a very high level treatment of the
topics for rank beginners in this 1957 edition. Remember that Popular Electronics
was a magazine intended to appeal to hobbyists with backgrounds in electricity and
electronics ranging from knowing how to insert batteries into a flashlight in the
proper direction (most of the time) to engineers and college professors. Part of
the publisher's mission was to introduce as many aspects as possible in order to
capture the interest of as many people as possible. They were pretty successful,
based on how long the magazine ran its course...
 This week's
crossword
puzzle is a new type that uses a "free form" layout where the software dynamically
creates the word grid, rather than beginning with a predefined grid that it then
fills with words. It appears the longer it is allowed to run, the greater the number
of words and cross-links it creates. After about 5 minutes, this 19x17 grid is showing
57 words and 61 cross-links... and now an hour later it shows 62 words and 70 cross-links
- not overly impressive in my view. The algorithm picks from the same database of
thousands of words which I have been creating for over twenty years and contains
only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, familiar company names 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 star like
Hedy Lamarr or a geographical location like Tunguska...
 Restoring and/or upgrading vintage radio receivers
is still a very popular pastime for hobbyists, and for that matter for some professional
servicemen who preform maintenance on established equipment installations. Three of the
most significant changes that can be made to older receivers to
improve sensitivity are to clean up the power supply DC output, replace
noisy components like vacuum tubes and leaky capacitors, and tune / modify /
replace RF and IF filters. This article discusses a method of replacing a stock
LC filter with a high selectivity mechanical filter. The nice thing about an
analog receiver is that narrowband, steep-skirt filters can be substituted
without concern for group delay at the band edges that can (and will) wreak
havoc on digital signals...
 Although the article's title specifies "electronic
hobbyist," the advice applies equally well to students and professional technicians and
engineers. A few of the
tools are no longer available from the original manufacturers, but modern
equivalents - often of better design and quality - are available. If you are
nostalgic for the originals, though, you can always look for them on eBay;
there's not much you cannot find there if you wait long enough. To show how much
times have changed, get a load of (pun intended) that pistol-shaped soldering
gun. Can you imagine the mayhem that would ensue if it showed up in a high
school electronics lab today? For that matter, is a classic Weller soldering gun
allowed? Can you even say "soldering gun?"...
 Electronic ignition, computer-controlled
fuel injection and air intake, alarm systems, radar, rear back-up cameras, GPS,
stereo sound systems, Bluetooth tire pressure monitors, hands-free telephones, automatic
headlight directors, drowsy driver detectors, collision avoidance, anti-lock brakes,
fuel efficiency management, air bag deployment, self-parking and even self-driving
features are now or soon will be standard features in automobiles. Mac McGregor
and Barney hit upon a lot of these items - some explicitly, some implicitly - in
this 1973 installment of "Mac's Service Shop" found in Popular Electronics
magazine. Amazingly impressive devices and systems are fermenting in the minds of
engineers and scientists today that will begin appearing in new car models a decade
or decades from now. While I am duly impressed, I would gladly trade my 2011 Jeep
Patriot for a nicely restored 1960s or 1970s pick'em-up truck. I'll add the desired
newfangled gizmos myself...
 If there was another episode of
Mac's Radio Service Shop where Barney was the primary teacher
and Mac was the student, I don't remember what it was. In fact, this is about as
total of a role reversal as there can be. First, Mac admits to having chased a presumed
oscilloscope issue down the proverbial rabbit hole only to realize the cause of
the problem was totally unrelated. Then, Barney produces a nifty device meant for
recording telephone conversations and demonstrates to Mac a couple ingenious applications
he discovered that were handy for troubleshooting television sets. When reading
Mac's description of using a magnet to alter the electron beam in a CRT, it reminded
me of how cool it was on the CRT displays to run a magnet...
 When
UHF broadcast television was being introduced, pundits - as pundits often
do - were quick to predict the rapid, imminent demise of the VHF channels. To
wit, "All current VHF stations (operating on channels 2 through 13) may be
scrapped, and operations shifted to the UHF band." That was in 1962, when the
first experimental UHF station (WUHF) went on-air in New York City. Cited as the
reason was a supposed inability for the two bands to co-exist. VHF channels 2-6
are on 54-82 MHz, 7-13 are on 174-210 MHz...
 Westinghouse Electric Company is, alas,
yet another of America's great founding businesses that is fading into oblivion.
Many are already gone, usually having been bought up by foreign conglomerates. In
an effort to be a "global player," we have surrendered our technology, manufacturing,
and brainpower all over the Earth - far too often to countries who would prefer
our demise. Out of thirst for power and money, politicians and bureaucrats bring
citizens of those adversarial countries here to populate positions (usually unelected)
of policy making or enforcing power. Some seem to be here for the purpose of warfare
if called upon (witness the millions of single, military-aged men pouring over our
southern border with no vetting). I worked for Westinghouse at the Oceanic Division
in Annapolis, Maryland, as an electronics technician back in the 1980s. Lots of
very bright engineers motivated me to earn my electrical engineering degree. Northrup
Grumman (still American, surprisingly) now owns that division. Judging by their
website, I'm guessing the primary product there is diversity, equity, and inclusion.
They might also build sonars...
 If terms like "magnetostriction," "mu-metal,"
and "D-ring" arouse your technostimulus receptors, then this quiz on
Magnetic Phenomena should be just what you've been waiting for.
It appeared in a 1962 edition of Popular Electronics, but the principles
therein have not changed since then. I must admit that I had never given thought
to the orientation in which bar magnets should be stored when in close proximity
to each other, especially since trying to store them the "wrong" way results in
them trying to reconfigure themselves to the "right" way automatically. Not mentioned
here is that a soft iron or other ferrous metal should be placed across the ends
to help concentrate the magnetic fields within the magnets, thereby reducing the
possibility of demagnetization due...
 Were strings of miniature Christmas tree
lights not available for purchase in 1955? This adventure of "Carl & Jerry" seems to imply that was the case since it concerns
the design and constructions of such a circuit using low voltage panel lamps (light
bulbs). Although usually the two techno-teenager are co-conspiring on various tasks
of high tech sleuthing or radio-related pursuits, but in this case if it Jerry who
has been doing the hard work. Author John Frye might not know how prescient he was
when describing the two inventions he conjured up for Carl and Jerry. The first
is the aforementioned miniature Christmas light string and the second is a voice
recording device that can capture a short message and then quickly play it back.
The playback scheme involves kids reciting their Christmas wish list to a fake Santa
Claus and then having him read it back to them in a different voice...
 Here is a quick
Hi-Fi Quiz for all you audiophiles out there. Although it appeared in a 1955
issue of Radio & Television News magazine, save for question #10 all
of Q's and A's still apply to today's equipment. Even that one can be easily guessed.
Q4 might seem a bit foreign, but think of the "groove" type as applying to 78, 45,
or 33-1/3 rpm platters and you'll do OK. Question #7 could be a baffler (pun intended
- you'll see how) were it not for one obviously invalid option that it takes an
RF guy (or gal) to recognize its inanity. Good luck. BTW, I missed Q1, but should
have known better.
 Did you know that the
Hallicrafters line of radios is named after founder Bill Halligan (W9WZE)? Hallicrafters,
founded in 1932, was a major manufacturer of amateur radio gear. During the years
of WWII they ruggedized some of their products to survive the harsh environments
of battle. Hallicrafters was sold to Northrop Corporation in 1966, at which time
the product line essentially ceased. Their gear is still very collectible by aficionados
of vintage Ham equipment. This story from the February 1943 QST magazine
provided an inside look at the production floor at Hallicrafters. Having cut my
figurative electronics teeth on radar and radio equipment built with tubes and point-to-point
wiring while in the USAF, and then later as an assembly/test technician at Westinghouse
Electric building sonar equipment for the Navy which included wiring chassis and
building large complex cable harnesses, I can personally relate to the photos accompanying
the article. When, for readers in the U.S., is the last time you saw a company touting
its "expert American craftsmen...
 As you might know, particularly if you are
a frequent RF Cafe visitor, amateur radio operators (Hams) were prohibited from
broadcasting during the entirety of World War II, ostensibly as a security
measure. The concern was that people might unintentionally (or intentionally) convey
information on troop positions and family names, domestic factory locations and
activities, and the general state of the nation in regards to attitude and finance.
Unlike today, that type of data was not easily gathered even by a dedicated deployment
of internal spies. In the early 1940s, the majority of amateur radio activity was
carried out in the form of Morse code, and operators were understandably concerned
about losing proficiency due to lack of use. In order to mitigate the opportunity
for "fist" atrophy, many Hams set up "wired wireless"
stations between residences and club meeting locations. This particular system was
designed to couple to the local overhead electric power lines, but there were also
private setups with dedicated lines between locations. Then, as now, one of the
biggest hurdles with conducting power-line carrier communications...
 In a continuing effort to provide archival
material for researchers and for anyone seeking information on a particular radio
restoration project, this Radio Service Data Sheet for the
Zenith Model 430/440 radio from a 1933 edition of Radio-Craft magazine
is being posted. An Internet search will show that there are many people engaging
in such activities. Restoring my Crosley Model 03BC console radio would have been
more difficult if not for others who have done similar work to assist the "community."
I generally despise the phrase "giving back" because it is usually uttered by people
that really owe nothing to anyone, but somehow feel obligated to do so or are conditioned
to automatically say such things. This is a case where I benefitted from somebody
else's work and there is an opportunity to return the favor...
 TGIF; the weekend is just hours away. While
you're waiting for the clock to get to quitting time, spend your final few minutes
enjoying this triplet of
electronics-themed comics that were in the February 1967 issue of Radio-Electronics
magazine. The page 37 comic would probably be one of the last featuring a self-service
vacuum tube tester as solid state TVs and radios were rapidly replacing tube types.
According to Wikipedia, the first Automatic Teller Machine (ATM) went into service
in June of 1967 (in the UK). That means the comic on page 92 was - most likely -
an unintentional preview into a world with ATMs in nearly every entertainment venue,
bank building, grocery and department store, and even government establishments.
Like with telephone cell towers, surveillance cameras, and hypodermic needles on
San Francisco streets, ATMs are everywhere you look nowadays. In-home television
servicemen who often confronted circumstances similar to the page 93 comic must
have gotten a real kick out of that one... |
