Today in Science History -
 Upsetters of apple
carts, rockers of boats, makers of waves, creators of stirs. All idiomatically
describe actions of those who commit the transgression of challenging accepted
norms. There is always someone claiming to have discovered the "truth" about one
subject or another. In the world of technology, most often the object of
contestation is which person was the "first" to have discovered, written, or
performed something. Here in this 1960 issue of Radio−Electronics
magazine, Mr. Leslie asserts that Thomas Alva Edison actually made the world's
first radio broadcast, not Guglielmo Marconi. For some reason the image of
Edison's "Means
for Transmitting Signals Electrically" patent omitted the ships at sea
overtop of the antenna structures, which seem to me to be critical in portraying
the "wireless" nature of the invention. His creative "spark" was motivated by
observation of a powerful spark and noting, "seemed so strong that it struck us
forcibly there might be something more than induction." Edward H. Loftin claims
the credit goes to Lt.-Commander Edward H. Loftin, U.S. Navy...
 OpenAI (ChatGPT) founder Greg Brockman,
recently produced a video introducing some of the improvements and new features
of GPT−4 (current public version is GPT−3.5). One thing he did was have the AI machine
asked it for a single sentence summary using only words beginning with the letter
"g." GPT−3.5 failed miserably, but GPT−4 succeeded. It even did a sentence using
only words beginning with the letter "q." He also had GPT−4 create a poem about
the tax preparation capability of ChatGPT (itself an impressive act). A few of the
vintage issues of Popular Electronics and the ARRL's monthly QST
magazine contained
electronics-related poems submitted by readers (see "Unpopular Radio," and "Pre-Radio,"
et al). Some are pretty clever. It takes some cogitation, skill, and creative ability
to come up with a rhyming poem on a technical subject like amateur radio. Since
I am in insufficient possession of the aforementioned qualities, I decided to task
ChatGPT to create a few topical poems for me. Is this amazing, or what? Be sure
to see "Ode on Rhode & Schwarz" and...
 Common sense never goes out of style, especially
as it pertains to
safety in the presence of electricity. Most people who have worked in the electrical
/ electronics realm for a while are aware that lethal electrocution can occur with
currents as low as 100 mA when it passes through the heart. Lower values cause
progressively less profound maladies, but in practice any level of current great
enough to be felt is not a good thing. I have written before about having received
a few pretty scary shocks when working on high voltage equipment and many lesser
jolts throughout my 50± years of exposure. Other than observing my father's being
leery of using of anything with an electric cord attached to it, my first formal
instruction about electrical safety was in my vocational classes in high school.
Instructor Russ Lorenzen taught us to keep one hand in our pockets when working
on live circuits, which of course was only to be done under the rare circumstance
when it is not possible to first turn power off. In practice that often meant when
doing so would be more inconvenient than the calculated risk of electrocution. Seriously,
though...
 "When you tap on your phone screen to check
something on the internet, you make use of wireless communications technology. With
the advent of 5G networks, this technology has made our lives easier than we could
imagine. As we progress towards 6G communication, the use of IoT devices to monitor
and perform tasks is becoming inevitable. As a result, there is a growing demand
for the services provided by such devices. However, the frequency resources accessible
to the IoT devices remain limited. Consequently, there has been a lot of research
focused on using various modulation schemes to fit in more data without causing
interference. Yet, however, they have ignored one important aspect of wireless communication:
conventional antennas respond to signals at the same frequency in the same manner.
However, if one were to modulate the antenna performance for a fixed frequency based
on other aspects of the signal waveform, like its pulse width, it would add a whole
new degree of freedom that can be exploited to transfer data efficiently... the
researchers put forth a new system that uses
'metasurfaces' to create waveform-based selectivity in antennas..."
 December is traditionally the issue for
magazines to sum up accomplishments of the ending year and make
predictions
for the next year. Radio-Craft magazine was no exception, but in 1936
they went ten steps farther and prognosticated a decade into the future - all the
way to 1946! It is actually a tongue-in-cheek reprint from Pathe News magazine.
However, note the drawing of 'professor teaches 2 million pupils,' where he is instructing
via television and the railroad company boss checking in on the conductors en route
via wireless teleconferencing. It might have seemed like a pipe dream in 1936, but
now it is commonplace. Not only do we now have live classroom broadcasts, but millions
of YouTube videos of instruction for performing just about every task and teaching
every subject imaginable...
 New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website 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. 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. I also re-broadcast homepage items on LinkedIn.
If you need your company news to be seen, RF Cafe is the place to be.
 Lotus Communication Systems began in 2009,
setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex
Country, Massachusetts. Lotus is committed to highest quality and innovative products.
Each RF/microwave module meets
exceedingly high standards of quality, performance and excellent value, and are
100% MADE IN USA. Lotus' RF/microwave products cover frequency band up to 67 GHz.
Lotus also offers an COTS shield enclosures for RF/microwave prototyping and production.
All products are custom designed. We will find a solution and save your time and
cost. Lotus has multiple 4 axis CNC machines and LPKF circuit plotters. In stock,
1-day free shipping.
 When I saw the photo of the
Vanguard III satellite in Figure 5 of this 1960 Radio−Electronics
magazine article, my thought was how much it looks like the Russian Sputnik satellite
with its spherical body and the antennas from four sides pointed upward. In fact,
the antennas were spring loaded to stick out perpendicular to the body after deployment,
as shown in Figure 1. The thick "horn" on the top is the magnetometer probe.
As can be seen in the schematic of the magnetometer circuit, solid state device
dominated the electronics, although almost certainly the transmitter used at least
one vacuum tube as a power amplifier. It can be argued that the "Space Age" would
not have been possible without solid state electronics because of size, weight,
power consumption, and reliability improvements over tube technology. These satellites
immediately followed the International Geophysical Year (IGY) activities conducted
on atmospheric parameters...
 Triad RF Systems designs and manufactures
RF power amplifiers
and systems. Triad RF Systems comprises three partners (hence "Triad") with
over 40 years of accumulated knowledge of what is required to design, manufacture,
market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA,
bi-directional, and frequency translating amplifiers are available, in formats including
tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology
partner than a vendor for our line-of-sight communications product line." Please
check to see how they can help your project.
 Elections have consequences, as the old
political says goes. If you're feeling the hurt of massive inflation over the last
two years, then you might also identify with another saying: Misery loves company.
You are not alone.
IEEE Spectrum
magazine uses data from "The Dice Tech
Salary Report 2023 Edition" to plot how while salaries have increased in dollar
numbers, the purchasing power has effectively gone down. "The numbers from job search
firms Dice and Hired have been released. These 2022 numbers have been eagerly anticipated,
given the turmoil generated by a spate of tech layoffs in the latter part of the
year, which Dice estimates at more than 140,000. The data they collect doesn’t allow
for apples-to-apples comparisons, but I've read through both reports, pulled out
data from past years to give the numbers some perspective when possible, and summarized
it in eight charts. Dice's numbers come from a survey administered to its registered
job seekers and site visitors between 16 August 2022 and 17 October 2022, for a
total of 7,098 completed surveys. Hired's analysis included data from 68,500 job
candidates and 494,000 interview requests..."
 This "Recent Tech
Headlines Quiz" challenges your ability to recall items from the homepage "Electronics &
Tech Headlines" column for the week of March 13, 2023. Except for the questions
and answers which I modified (and added two more sets), every line of JavaScript
code for this multiple-choice quiz was generated based on a query made to the ChatGPT
engine from OpenAI. It also generated code for the PHP language, and will presumable
do so for many other computer languages. Just for the heck of it, I had ChatGPT
generate a version of the quiz code in the COBOL language. COBOL, if you are old
enough to recall, the a primary mainframe computer language before the PC era, and
was a big deal during the run-up to Y2K because legacy code could not handle the
century change. Lots of gray-haired, retired COBOL programmers made big bucks helping
coders port code to C++, Delphi...
 Modelithics and International Manufacturing Services
(IMS) have expanded their long term collaboration commitment for an additional
six (6) years, which includes development of simulation models for several additional
IMS device families, as well as renewing their Sponsoring Modelithics Vendor Partner
(MVP) status. Additional high frequency Modelithics Microwave Global Models™ for
multiple IMS resistor and attenuator families are planned under the extended agreement.
J.J. Silvia III, IMS Vice President, General Manager, states: "IMS is excited to
continue this partnership. Applying bench-test data to scalable models found in
their library not only provides valuable performance validation, but also benefits
our customer design speed and capabilities. High tech customers design with high
tech tools that are supported by Modelithics' software...
 This Radio Service Data Sheet covers the
Ford-Philco model FT9, 6-tube auto-radio receiver. It appeared in a 1936 issue
of Radio−Craft magazine. Most - if not all - electronics servicemen had
subscriptions to these magazines because they were a ready source of not just these
service sheets, but because of the extensive articles offering advice on servicing
radios and televisions. In fact, many electronics manufacturers had a policy of
supplying service data only to bona fide shops. Thumbnail photos at the left came
from a Ford-Philco FT9 radio on eBay. A large list is included at the bottom of
the page of similar documents from vintage receiver schematics, troubleshooting
tips, and alignment procedures. They were originally published in magazines like
this one, Radio and Television News, Radio News, etc. I scan and
post them for the benefit of hobbyists who restore and service vintage electronics
equipment...
New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website 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. 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. I also re-broadcast homepage items on LinkedIn.
If you need your company news to be seen, RF Cafe is the place to be.
 Axiom Test Equipment allows you to
rent or
buy test equipment,
repair
test equipment, or sell or trade test equipment. They are committed to providing
superior customer service and high quality electronic test equipment. Axiom offers
customers several practical, efficient, and cost effective solutions for their projects'
TE needs and is committed to providing superior customer service and high quality
electronic test equipment. For anyone seeking a way to offload surplus or obsolete
equipment, they offer a trade-in program or they will buy the equipment from you.
Some vintage items are available fully calibrated. Please check out Axiom Test Equipment
today - and don't miss the blog articles!
 This custom RF Cafe
electronics-themed crossword puzzle for March 19th contains words and clues
which pertain strictly to the subjects of electronics, mechanics, power distribution,
engineering, science, physics, astronomy, chemistry, etc. If you do see names of
people or places, they are directly related to the aforementioned areas of study.
As always, you will find no references to numbnut movie stars or fashion designers.
Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds
of them dating back to the year 2000. Enjoy.
 This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers"
Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's"
design has been ripped off by other people and used on their products, so please
be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢ per
item - Cafe Press gets the rest of your purchase price. These would make excellent
gifts for husbands, wives, kids, significant others, and for handing out at company
events or as rewards for excellent service. It's a great way to help support RF
Cafe. Thanks...
 Centric RF is a company offering from stock
various RF and
Microwave coaxial components, including attenuators, adapters, cable assemblies,
terminations, power dividers, and more. We believe in offering high performance
parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz at power
levels from 0.5-500 watts are available off the shelf. Order today, ship today!
Centric RF is currently looking for vendors to partner with them. Please visit Centric
RF today.
 By the time this "Test
Transistors Fast" article appeared in a 1969 issue of Radio-Electronics
magazine, the use of vacuum tubes in new designs had been relegated to the domain
of hobby and specialized circuits. Very high power and frequency applications were
still waiting for semiconductors capable of servicing such equipments, but the electronics
industry, particularly the domestic consumer world, used transistors and what was
available in the form of integrated circuits. While designers had already been using
transistors for a decade or more, many of the aforementioned hobbyists and electronics
repair servicemen were still getting accustomed to the newfangled technology and
welcomed the publishing of these kinds of topics. In 1969, the only thing I knew
about transistors was that they must have somehow been associated with the "transistor
radio" I carried in my jacket pocket. It was too small to contain any of those glowing
tubes we still had in our household TV set and tabletop radios (and in the dashboard
of our family's 1960 Rambler auto for that matter), so surely there was a difference...
 This "RF and EMC Formulas and Charts" poster by
AR RF/Microwave Instrumentation, a manufacturer of amplifiers, antennas, anechoic
chambers, and related equipment, is a great resource to have in your lab or at your
desk for a handy and quick reference for the EMC professional. This poster covers
the basics such as frequency-to-wavelengths and Ohms law relationships, Linear to
Log conversions, as well as EMC-targeted content such as radiated field strength
and antenna factor calculations. It also includes conversions for a 50 Ω environment,
common EMC equations, VSWR conversion charts, antenna equations, unit conversions,
and more. It is a great addition to any EMC lab. Other poster themes may also be
downloaded...
 If
you have only ever known a time in the R/C era when 2.4 GHz, spread spectrum
radios were in use and not only were there no interference issues, but there were
no licenses required, either, for legal operation, then it might be hard to imagine
when this was not so. Most people in the R/C realm at least remember the 72 MHz
frequency band where each system operated on a specific center frequency, where
no two systems could be operated in the same vicinity. Before that there was the
27 MHz band, which is where I began, more specifically on 27.195 MHz.
Only five frequencies were reserved by the FCC exclusively for radio control use.
That meant never more than five planes in the air, or even being worked on with
the radio on, at a time. The band was part of the original Citizens Band (CB) radio
allocation. Commercial CB radios were notoriously lousy at controlling bandwidth
and often overlapped the R/C bands with enough power to cause deadly (to a model)
interference. My FCC operator's permits (Class
C and Class D), obtained sometime around 1972, is long gone...
 2.1 GHz (5.6-inch, or 14 cm wavelength)
radio waves were an almost totally unexplored realm in 1930, with it and higher
frequencies being the domain of theoretical research laboratories. Signal generators
capable of producing much more than a few hundred megahertz were rare even in commercial
applications. As reported here, centimeter−length electromagnetic waves were "according
to the theories of Barkhausen and Kurz, [the] result of purely electronic vibrations,
whose frequency was determined only by the operative data of the tube and was not
dependent on any internal or external oscillation circuit." A half-wave receiving
antenna picked up the transmitted signal with a simple diode detector to enable,
after a couple stages of amplification, an audible signal. These are some of the
earliest experiments at RF with parabolic metallic reflectors and polarization with
a diffraction grid that could be rotated to set the polarization direction...
 Long distance communications via satellite
were a few years off when
Pacific Scatter Communications System (PSCS) was established as a network of
microwave radio relays that spanned the Pacific Ocean during the Cold War era. It
was established by the U.S. in the late 1950s as a means of maintaining secure communications
with its military and diplomatic installations in Asia, particularly in Japan and
South Korea. PSCS consisted of a series of shortwave and microwave relay stations
located on islands throughout the Pacific, including Hawaii, Guam, Saipan, Okinawa,
and, as reported in this 1960 issue of Radio−Electronics magazine, Wake
Island. The system was designed to be highly resilient, with redundant communication
paths and backup power supplies to ensure that communication could be maintained
even in the event of a nuclear attack. It played a critical role in supporting military
operations during the Vietnam War and in maintaining diplomatic relations with allies
in Asia. The PSCS was eventually superseded by more advanced satellite communication
systems in the 1980s...
 Website visitor Jared Finan contacted me
a few days ago to ask whether I had any idea why noise figure and
Y−factor measurements made with his HP/Agilent/Keysight 8975A Noise Figure Meter
were not in agreement. The same measurements made with his HP/Agilent/Keysight 8970A
- a much older piece of equipment - agreed very well. My suggestion turned out to
not be the answer. Jared wrote back later saying he found the cause of the problem
- a real exercise in troubleshooting! He gave his permission to post our dialog
here so in case someone else might have been plagued with a similar issue. There
are several methods for measuring noise figure, including the Y-factor method, the
cold source method, and the hot/cold load method. The Y-factor method is the most
widely used technique for noise figure measurement...
 This "drive-by" schematic and parts list
for the
Admiral Model 7C64 vacuum tube console radio and phonograph appeared in the
February 1948 issue of Radio News magazine. I refer to it as "drive-by"
because there was no description or maintenance verbiage provided. You might not
expect from the relatively simple circuit that the entire Model 7C64 was mounted
in a multi-sectioned wooden cabinet that included a phonograph. The thumbnail at
the left is from the RadioMuseum.org website - a great source for research on vintage
vacuum tube radios. Admiral Radio is a brand of electronic products that was founded
in Chicago in 1924. The company started out as a manufacturer of phonographs and
radios. In 1971, Admiral Radio was acquired by Panasonic.
 This is the second and final installment
of an article on the topic of
frequency modulation (FM) that began with Part 1 in the July 1941 edition
of Radio-Craft magazine. Author Raymond Guy, a radio facilities engineer at the
National Broadcasting Company (NBC), covers all the fundamentals of FM (a relatively
new concept at the time, invented by Major Edwin Armstrong) not just from a functional
circuits perspective but also pointing out a broadcaster's concern for channel spacing
and broadcasting ranges. Transmitter pre-emphasis, receiver de-emphasis, noise thresholds,
and adjacent channel and co-channel broadcasting strategies are discussed here...
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