|
 We
take for granted today that we are able to legally use radio control systems without
obtaining an
operator's license, but that has only been the case since the late 1970s. Prior
to that, a Citizens Radio Station License needed to be procured from the Federal
Communications Commission (FCC). No examination was required, but a fee was charged.
I think mine cost something like $5. FCC Part 15 rules permitted license-free
operation in designated frequency bands then as it does now, with a limit on maximum
power output for both intentional and unintentional...
 "As
we march toward 2030, the relentless demand for wireless data is reshaping the landscape
of connectivity. Meeting this demand requires a well-orchestrated strategy to secure
new spectrum and optimize existing bands. The
success of 6G, with commercial deployments expected to start around 2030, hinges
on the timely availability of spectrum. Given the complexity of the spectrum allocation
process, initiating activities to ensure spectrum readiness for 6G are imperative
and cannot be delayed..."
 Robert Radford's (not to be confused with
Robert Redford) "Electromaze"
is a unique - and weird - sort of word puzzle that appeared in the April 1966 issue
of Popular Electronics magazine. You will probably want to print out the maze grid
and find an old guy who should still have a pencil stowed away somewhere you can
borrow to use for filling in the boxes. Note that in my opinion the answer given
for clue number 2 is technically wrong. What say you?
 "NASA's Jet Propulsion Laboratory
(JPL) and the historic Mount Wilson Observatory in California appear to be unscathed
by the Eaton fire burning through Pasadena and Altadena - for now. However, over
150 JPL employees have lost their homes, said the center's director Laurie Leshin
in a post on X on Friday morning. The center lies in the foothills of Pasadena,
within the Eaton fire's mandatory evacuation zone. The Eaton fire, which has burned
14,000 acres and 5,000 structures as of Friday afternoon, is one of several fires
raging in the L.A. region this week amid dangerously high winds and dry conditions..."
 Sometime around late 1977, a year or so
prior to reporting to Lackland AFB for Basic Training with plans to pursue a career
in electronics, I began boning up on my admittedly lacking electronics skills. Having
spent the past few years as an electrician, including a couple years in vocational
school, I was familiar enough with the big stuff that could easily kill me, but
I didn't know much about about electronics with its small components and low voltages.
To assist me with my goal, I purchased a couple Heathkit kits and carefully studied
all the information provided, then proceeded to assemble and test everything. My
first project was this
IM-17 Utility Solid-State Voltmeter. It was simple enough...
 The September 1966 issue of Radio-Electronics
magazine had a plethora of good News Briefs, including an item where editor Hugo
Gernsback is presented with yet another honor - this time from the International
Press Group. It's like today with Dr. Ulrich Rohde (N1UL), who, deservingly, seems
to be receiving new commendations and awards on a regular basis. In the "Famously
Wrong Technology Predictions" department, COMSAT's president, Dr. Joseph
Charyk, declared that direct satellite-to-home television broadcasting was not a
likely possibility. Sylvania's General Telephone & Electronics...
 "Scientists are making significant strides
in creating
nuclear clocks, a new frontier in ultra-precise timekeeping. Unlike optical
atomic clocks that depend on electronic transitions, nuclear clocks harness the
energy transitions within atomic nuclei. These transitions are less influenced by
external forces, offering potentially unparalleled timekeeping accuracy. Despite
their promise, nuclear clocks face steep challenges. The isotope thorium-229, essential
for these clocks, is rare, radioactive, and prohibitively expensive in the required
quantities. In a recent study published..."
 A
time domain reflectometer (TDR) is an electronic instrument designed to characterize
and locate faults in electrical transmission lines and cables. It works by sending
a fast rise-time pulse down the cable and measuring the reflected signal. The time
it takes for the signal to return, combined with its amplitude and polarity, provides
information about the location, type, and severity of faults in the line. The principle
behind the TDR is based on transmission line theory and wave reflection phenomena,
making it a cornerstone in cable diagnostics and electrical engineering. The TDR
was first conceptualized in the early 20th century as wave propagation and reflection
principles were better understood, but practical devices emerged...
 "A massive fire broke out at a Californian
power plant early Friday morning, threatening one of the largest
battery energy storage facilities in the world. The blaze began in a building
containing lithium-ion batteries hours earlier, an official at the Monterey County
Sheriff's office told the BBC. The Moss Landing power plant was evacuated. No injuries
were reported. Officials are
not actively fighting the fire, the Monterey Sheriff
spokesperson said, and are instead
leaving the building and the batteries to burn on the advice of fire
experts. Hundreds of people have been ordered to evacuate..."
 To be honest, I don't know whether
military electronics training commands the respect in private industry that
it did back in 1982 when I separated from the USAF. If you left the military within
the last 20 years or so and care to share your experience with seeking civilian
employment, I'll be glad to add it here as a side note. Many of the electronics
technicians I worked with both as a tech myself and then as an engineer (after earning
a BSEE) got their initial classroom training in either the Air Force or the Navy.
There were probably some from the Marines and Army, but I don't recall any off-hand.
I hate to admit it, but I think the Navy vets were even more highly sought...
 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 ceramic bandpass filter models have been added to the product line in January,
including a 2250 MHz ceramic bandpass filter with a bandwidth of 225 MHz,
a 2140 MHz ceramic bandpass filter with a bandwidth of 60 MHz, and a 2190 MHz
ceramic bandpass filter with a bandwidth of 40 MHz, all with insertion losses
of <2 dB...
• 24%
Growth for Semis in 2024
• EU
Probes Gorilla Glass on Smartphone Monopoly
• Plea
for AM Act Passage After Helene
• Cost Concerns &
Confusion in Broadband Market
• Touchscreens Out; Buttons &
Dials Back In (good!)
 This is the most intense episode of John Frye's
"Carl & Jerry" series I can remember. It appeared in the January 1959 issue
of Popular Electronics magazine. There have been many adventures both before
and after this one where the electronics-obsessed teenagers assisted local police
and firefighters, and even a Fed or two occasionally. Usually, they are called upon
to find hidden evidence, track bad guys, listen in on their phone or radio conversions,
and other missions requiring high-tech methods. Other times they stumble into involvement.
In
The Little "Bug" with Big Ears," a girl has been kidnapped and the perp threatens
to rub her out if ransom...
 This is Part 3 of a 3-part series of articles
on
atomic radiation that appeared in Electronic World magazine in 1969.
It deals with measurement techniques and equipment. Shippingport Atomic Power Station,
the first full scale nuclear power plant in the United Sates, went operational in
1957. It marked the dawn of a new era of electric power generation that was filled
with grandiose predictions of limitless, non-polluting, dirt cheap power. Everything
was going to be powered by electricity - air heating and cooling, lighting, automobiles,
refrigeration, cooking, water heating. Atomic power was going to be a figurative
and almost literal beating of swords into ploughshares as the destructive energy...
 Transcat | Axiom Test Equipment, has published
a new blog post that covers how
AC Power Sources are able to support AC/DC power testing according to numerous
industrial and military standards. These power sources are available with software
to coordinate standards-based AC/DC power testing with single-, two-, and three-phase
power supplies. Industrial standards such as IEC 61000-4-11 and IEC 61000-4-13 from
the International Electrotechnical Commission (IEC) and military standards such
as MIL-STD-704 are just a few of the solid guidelines for AC power testing; they
are typically programmed into the test software available for modern AC power sources.
Measurement-grade AC electrical power sources...
 While far from being an expert in the use
of hand tools and small powered shop tools, I have built enough prototypes and models
in more than six decades to have learned a fair amount about what results in success
and failure. Admittedly, there have been times when quality has been sacrificed
for the sake of cost and/or expediency. Personal safety has sometimes been risked
as well - usually for no real good reason. Luckily, I still have ten fingers, two
working eyes (although very near-sighted), and excellent hearing. Surely, you possess
none of my bad habits ;-) This article from Popular Electronics magazine
offers advice on how to properly work with PCBs...
 The
Wireless Telecom Group,
comprised of Boonton, Holzworth, and Noisecom, now a part of Maury Microwave, is
a global designer and manufacturer of advanced RF and microwave components, modules,
systems, and instruments. Serving the wireless, telecommunication, satellite, military,
aerospace, semiconductor and medical industries, Wireless Telecom Group products
enable innovation across a wide range of traditional and emerging wireless technologies.
A unique set of high-performance products including peak power meters, signal generators,
phase noise analyzers, signal processing modules, 5G and LTE PHY/stack software,
noise sources, and programmable noise generators.
 My guess at the solution for the "Unsquare
Waves" challenge in "What's
Your EQ" feature of the July 1964 Radio-Electronics magazine was wrong,
but would have been reasonable for a more modern oscilloscope. I thought maybe the
compensation capacitor in the o-scope probe was way out of adjustment. Since the
author provides a schematic of the oscilloscope input circuit, you will probably
spot right off what the cause of his unexpected waveform was. The other problem
is a fairly simple, first-year electronics course deal. As the title of it suggests,
you'll need to take into account the charge on each capacitor to most easily arrive
at the answer...
 "For homeowners, moisture buildup can cause
the biggest headaches. Mold grows on drywall and wood-based materials, creeping
along walls, floors and ceilings. Building materials begin to erode and rot. As
insulation becomes damaged, the home's energy-efficiency decreases. Even human health
suffers, as moisture also leads to air-quality issues. The key to preventing extensive
moisture damage is discovering it early, when it can be easily fixed. Researchers
at the Department of Energy's Oak Ridge National Laboratory are using
microwave radar reflection to nondestructively detect and measure..."
 "You
get what you pay for," is an admonishment which has been around for a long time,
and it applies generally to many situations. Radio-Craft magazine editor
Hugh Gernsback took the occasion of a meeting with a successful radio repair technician
to pen this piece illustrating how it is not only the consumer who gets hurt by
low-cost hucksters. Gernsback's discussion with a for-real electronics technician
from Ohio serves as a real-world example. A fictitious Serviceman, whom he assigns
the moniker of Mr. G.O. Getter (a play on the vacuum tube term "getter"), suffers
from the bad reputation brought to his electronics...
 For your convenience, everything RF
has created the most extensive
EMC Testing Company Directory on the Internet which includes all of the leading
EMC Testing Labs from around the world. Based on your specific needs, you can use
the filters on the left-hand side to identify EMC Testing Labs based on their location
and capabilities. Further select from international approval type (CE, FCC, UKCA,
G-Mark, etc.), testing services (radiated and conducted immunity, radiated and conducted
emissions, military standards, SAR, surge testing, etc.), industry segment (electronics,
industrial, medical, etc.), services (shielding effectiveness, consultation, pre-compliance,
risk...
 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 when this Short Wave Craft magazine article
was published 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...
 Please take a few moments to visit the
everythingRF website to see how they can assist you with your
project. everythingRF is a product discovery platform for RF and microwave products
and services. They currently have 333,423 products from more than 2198 companies
across 460 categories in their database and enable engineers to search for them
using their customized parametric search tool. Amplifiers, test equipment, power
couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers,
power supplies, and everything else. Please visit everythingRF today to see how
they can help you.
 For a few years, each month's edition
of Radio-Electronics magazine included a column entitled "The
Radio Month," which was a collection of a dozen or so relevant news items. The
March 1953 issue reported on transistorized hearing aids (those old vacuum tube
types didn't fit in your ear very well), how the number of TV sets in the U.S. had
out-paced the number of telephones thanks to new UHF channels, the continued rapid
expansion of television in Europe, and the upcoming 1953 I.R.E. Show (Institute
of Radio Engineers) in New York City. Of particular note was the new germanium ore
source discovered in Kentucky - not the first place I think of with a semiconductor
mother lode. At the time, germanium (Ge) was still the primary element used in transistors
and diodes, although silicon was making rapid inroads. The story was germanium sold
for $350 per pound in pure metallic form...
 "MVG, a leader in electromagnetic solutions,
has launched its innovative
Reverberation Chamber, designed to excel in immunity testing and applications
requiring extreme field strengths from 200 V/m to 7000 V/m. The chamber
incorporates a sophisticated paddle system that enhances performance across a broad
frequency range, particularly at lower frequencies, and adheres to the IEC61000-4-21
EMC testing specification. This chamber is ideal for EMC compliance testing in line
with emissions and immunity standards for electrical and electronic products..."
 Immersion Tin, also known as White Tin,
stands out as a RoHS-compliant (lead-free) PCB surface finish ideal for flat surface
needs and fine pitch components. San Francisco Circuits' application of Immersion
Tin involves applying a thin layer of tin onto the copper layer of a PCB, offering
exceptional flatness that supports small geometries and surface mount components.
This finish is also one of the most cost-effective immersion coatings, making it
a popular choice for budget-conscious designs. Despite its affordability, Immersion
Tin has some limitations, including a shorter shelf life (3-6 months) and susceptibility
to tin whiskering. It's primarily used as a sustainable alternative to lead-based
finishes, requiring fewer resources during its application. Its reworkability and
flat surface make it an excellent choice for fine pitch components and BGA assemblies....
 S-units are probably not familiar at all
to non-Hams since they refer to receiver signal levels (the "S" stands for "signal").
It is a relative unit of measure rather than absolute. Technically, the dBm unit
of power is also a relative unit, but it is referenced to a fixed power level of
1 mW - traceable back to primary standards at NIST or any other country's standards
keeper. By contrast, the S-unit - at least originally - is relative to the strongest
useable signal level at a particular receiver's input. An indication of S9 meant
a maximum signal level was present at the input based in part on the receiver's
dynamic range at a certain frequency...
 If you believe the claims and the radiation
pattern plots and graphs presented in this 1962 Radio-Electronics magazine
advertisement, then JFD Electronics had a pretty nice
television antenna. Per the data, reception gain was nearly perfectly flat across
the lower channel band (2-6) and across the upper channel band (7-13). That is the
VHF band. Model LPV-11 is featured in the image and the data. It was an 11-element
log-periodic antenna with "9 Active Cells and 2 directors," with an effective range
of 100 miles. UHF, covering channels 14-83, occupied the 470-884 MHz band.
1962, the year of this article, is the same year that the All-Channel Receiver Act
which compelled manufacturers to include UHF reception on all new TV sets. The only
show I remember watching on UHF was Bob Ross (a career USAF technician) painting
"happy little trees" on PBS...
|
 July 26th's custom
Radio 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 Lamarr or the Bikini Atoll, respectively. Avid cruciverbalists
amongst us: the gauntlet has been thrown down.
 Here are a couple more
electronics-themed comics from a 1940-era issue of Radio News magazine.
The scenarios depicted in these old comics are often based on the real-life experiences
of radio and electronics servicemen. No doubt many guys got clobbered by high voltage
or deafening audio when a customer decided to power up a television or radio while
being worked on in the home. When this comic with the police car radio appeared
in 1940, it had only been a decade since the first 2-way radios were being installed
in patrol cars (see "A New Arm of the Law"). A huge list of technology-themed comics
is listed at the bottom of the page. Enjoy!
 Here is another of the "Radio
Term Illustrated" type of comic, which appeared in the December 1939 issue of
Radio News magazine. The DXing Hams can get a bit animated when trying
to squeeze the last picowatt out of a long distance contact. I'm not sure why the
guy is depicted as a country hick when for certain there were plenty of polished
city slickers who resorted to the same antics. A big list of other electronics-themed
comics is at the bottom of the page, many of which contain other of the "Radio Term
Illustrated" style.
 Bell Labs, having been responsible for creating
the first positive amplification point contact transistor just before Christmas
1947, continued to lead the way in semiconductor research and new product announcements
for many decades. This little tidbit was tucked away at the bottom of page 120 in
the May 1954 issue of Radio & Television News magazine. It reported on "the
purest substances in the world" being created there in the form of 99.99999999%
(aka 10N)
pure germanium crystals, which are used as seed for growing boules for device
production. That's one rogue impurity atom in ten billion germanium atoms. Modern
monocrystalline silicon boules are typically 7N or better...
 The newest release of RF Cafe's spreadsheet
(Excel) based engineering and science calculator is now available -
Espresso Engineering Workbook™. Among other additions, it now has a Butterworth
Bandpass Calculator, and a Highpass Filter Calculator that does not just gain, but
also phase and group delay! Since 2002,
the original Calculator Workbook has been available as a free download.
Continuing the tradition, RF Cafe Espresso Engineering Workbook™ is
also provided at no cost,
compliments of my generous sponsors. The original calculators are included, but
with a vastly expanded and improved user interface. Error-trapped user input cells
help prevent entry of invalid values. An extensive use of Visual Basic for Applications
(VBA) functions now do most of the heavy lifting with calculations, and facilitates
a wide user-selectable choice of units for voltage, frequency, speed, temperature,
power, wavelength, weight, etc. In fact, a full page of units conversion calculators
is included. A particularly handy feature is the ability to specify the the number
of significant digits to display. Drop-down menus are provided for convenience...
 Recognizing that many people were reluctant
to approach the theoretical aspect of electronics as it applied to circuit design
and analysis, QST magazine (the American Radio Relay League's monthly publication)
included equations and explanations in many of their project building articles.
Occasionally, an article would be published that dealt specifically with how to
use
simple mathematics. In this case, the June 1944 edition, we
have the second installation of at least a four-part tutorial that covers
resistance and reactance, amplifier biasing (tubes since the
Shockley-Bardeen-Brattain trio hadn't invented the transistor yet) oscillators,
feedback circuits, etc. In the July 1944 edition is the third installation
of at least a four-part tutorial that covers resistance and reactance,
amplifier...
 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...
 Being the birthday of Dr. Robert W.
Wilson, there is no better occasion to post this article about the "sugar-scoop" antenna used by the two Bell Telephone Labs engineers
(the other being Dr. Arno A. Penzias) who serendipitously discovered the cosmic
microwave background radiation (CMBR) believed to be a signature of "The Big Bang."
The pair were investigating an unexplained hiss in the background of the very low
noise receiver attached to the antenna. That microwave energy was constant and came
from all areas of the sky, regardless of where the antenna was pointed. They eventually
deduced that the signature was consistent with...
 For a few years, Popular Electronics
magazine ran an electronics-themed single-panel comic feature called "Parts
Talk." Jack Schmidt was the artist for the series, and is evident by the "Thanks
Joe Cox" on the page 49 comic, he must have used ideas for topics submitted by
Popular Electronics readers. From today's perspective of grain-of-salt
size surface mount components, the claim of "It's a small world," by that
vertical-mount capacitor doing the talking is very dated. Compared to its
previous generation of vacuum tubes and discrete components that needed to
handle higher voltages and power dissipation, these through-hole printed circuit
board (PCB) components are a small world. Another half a century from now, the
need for discrete, off-chip components...
 "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...
 Raytheon is another of the stalwart
early American electronics and technology manufacturing company. It began
operations in Cambridge, Massachusettes in 1922 under the name of the American
Appliance Company. The name was changed to
Raytheon in 1925 to reflect its growing vacuum tube usiness. Did you know
the name Raytheon means "light from the gods?" In this case, the light refers
to the orange glow from the tube heater filiment. If you have ever had the
privilige of seeing in a darkened room vacuum tubes glowing inside a vintage
radio, you will understand the relationship to a godly sight. Not too many
years ago, there were still a few companies like Tesslor manufacturing new
tube radios, but now you'll have to go to eBay or similar venues to find used
radios. The prices are not too bad. ...but I digress. This 2-page advertrisement
in a 1955 issue of Radio & Television News magazine pitched a division...
 This week's RF Cafe crossword puzzle contains the
usual assortment of engineering and science related words and clues, but there are also
a few specific words commemorating our
Thanksgiving
Day holiday (indicated by a asterisk *) that is celebrated
each year on the fourth Thursday of November. Macy's 90th Thanksgiving Day Parade occurs
on the morning of November 24th and follows a route along Central Park West and 6th Avenue.
Interestingly, the parade was cancelled during the World War II years of 1942, 1943,
and...
 Here is a little electronics hobbyist humor
in the form of a comic series titled "Hobnobbing with Harbaugh," compliments of
Popular Electronics artist Dave Harbaugh. Citizens Band radio and dirty
hippies were the topic of the day in the 1970s, so that's what you see in a
couple of these comics. I got my first 23-channel CB radio (FCC mandated 40
channels in 1977) in 1976 and installed it in my 1969 Camaro SS hot rod. It
required a Class D radio operator license at the time, but shortly thereafter no
license was needed. The "Inventions Wanted" comic is my favorite, followed by
"Mayday... Mayday!" You don't need to be an amateur radio operator to appreciate
these comic strips...
 Before most people listened to radio and
television programming via cable, satellite, and/or the Internet, broadcasts were
received over the air, usually from local stations. A common problem in the days
of vacuum tube Ham transmitters back in the day was inadvertently causing
broadcast interference (BCI) or specifically in the case of television, TVI,
due to insufficient filtering, shielding, or design. Nowadays, we generally refer
to all such unintentional and incidental radiation as radio frequency interference
(RFI). Lots of articles were written on the subject in the 1940s through about the
1970s. Some RF spectrum is shared by more than one entity per FCC and other countries'
band plans, with primary and secondary allocations assigned for some. For example,
in the U.S., the 33 cm amateur radio band coexists with the 902-928 MHz
unlicensed Part 15 ISM (Industrial, Scientific, and Medical) band. Ditto for some
of the other ISM bands. If you're not a Ham, you might be surprised to learn that
licensed amateurs have primary rights to the band's use...
 Since I don't have another Popular Electronics
electronics quiz for this week, hopefully these
electronics-themed comics will suffice as Friday afternoon relief at the end of a
tough work week. My favorite is the one with the Ham dude misinterpreting advice and
connecting his antenna to... well, you'll see. The other two are pretty good as well.
There is a yuge (a little NYC lingo) list of other technology-themed comics at the bottom
of the page...
 Punch cards have been used in computer systems
since the very early days of digital programming. They were probably the first form
of read-only memory (ROM), come to think of it. I hate to have to admit it, but
the meager computer used in my high school computer lab (circa early-mid 1970s)
used
punched cards. I never took the class, but stories abounded of how pranksters
would shuffle a stack of punch cards while the student programmer wasn't watching
and then get a good laugh when nothing worked. There are also plenty of cases where
a stack was inadvertently knocked onto the floor and had to be laboriously re-ordered.
IBM is the brand that comes to most people's minds when thinking about the old punched
card computer systems, but other companies like NCR (National Cash Register), HP
(Hewlett-Packard), DEC (Digital Equipment Corporation), and plenty of others others...
 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...
 Cruciverbalists rejoice! Here is another
tech-related crossword puzzle to try your technical prowess. Unlike the weekly
RF Cafe crossword puzzle that contains only engineering, science, mathematics and
other tech words, this one from Electronics World does have a few unrelated
words. The big difference between making crosswords then and now is Mrs. Le Fevre
had to construct the grid of words manually, whereas I just create a huge file of
words and definitions, draw the grid outline, and then click a button to have software
put it all together. I'm guessing it took a couple hours to make this puzzle...
 This is really clever. Appearing in the March
1955 edition of Popular Electronics magazine, "The
Electronic Husband" article is one wife's attempt to quantify her husband's
interest in all things electronic by adapting forms of Ohm's Law to fit observed
behavior. In the process of writing the parody, Mrs. Jeanne DeGood demonstrates
an impressive basic knowledge of Mr. DeGood's second passion (Mrs. DeGood
being his first, presumably). After all the articles that Melanie has proof read
for me, she knows a lot of these equations just as well, even if she doesn't know
what they mean...
 Although not specifically stated, some of
the technology reported in this August 1945 issue of Radio-Craft magazine
was not so long before classified technology developed during World War II.
The
Radiotype system of wireless teletype developed by General Electric
was an early attempt to provide a mobile means of sending and receiving hard copy
messages. It was a rather complex scheme that used a typewriter to drive a tape
punching apparatus, which was fed into a radio transmitter to send coded tones (as
opposed to CW pulses) for a receiver to then decipher and drive an Electromatic
typewriter. The demonstration used a police car to carry remote equipment. In related
news, RCA's wireless 488 word-per-minute (wpm) telegraph multiplexer using time
division multiplexing (TDM) Also featured was the FCC's decision to move the commercial
broadcast FM band from 54-88 MHz up to 88-106 MHz (now up to 108 MHz...
 This entry level introduction of
differential calculus as it applies to electronic circuit analysis appeared
way back in a 1932 edition of Radio News magazine. It was written by none
other than Sir Isaac Newton himself (just kidding, of course). Author J.E. Smith
created an extensive series of lessons that began with simple component and voltage
supply descriptions and worked up through algebraic manipulations and on finally
to calculus. I remember not being the best math student in high school (OK, one
of the worst), but once I got an appreciation for the power of mathematics for analyzing
electronics, mechanics, physics, and even economics, my motivation level soared
to where I craved more of it and ended up receiving "As" in all my college math
courses. That is truly an indication that while not everyone can excel at math,
the proper environment can make a world of difference... |
