Today in Science History -
 I believe this April 19, 1965 article in
Electronics magazine by Gordon E. Moore was the very first instance
of what has come to be known as "Moore's
Law." His opening statement, "The future of integrated electronics is the future
of electronics itself," might seem obvious in retrospect, but remember that at the
time the world was struggling - primarily psychologically and emotionally - with
a transition from vacuum tubes to semiconductors. There was a lot of resistance
to the replacement of tubes. He further prognosticated, "Integrated circuits will
lead to such wonders as home computers...," and, "That means by 1975, the number
of components per integrated circuit for minimum cost will be 65,000. I believe
that such a large circuit can be built on a single wafer." In the age of germanium
and silicon, Mr. Moore wrote that gallium Arsenide (GaAs), a semiconductor
compound almost nobody had ever heard of, would be necessary for high frequency,
high power devices, including integrated multiple-stage amplifiers. Did the man
call it or what?
 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...
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 While reading through this article on copper-oxide
rectifiers, I am once again reminded of how much we take for granted the conveniences
of electrical test equipment on today's shop benches. The advent of FET-input multimeters
was a huge step forward because the meter input impedance is so high that it has
practically no impact on the circuit being measured. Prior to that, most simple
meters drew their power from the circuit under test, thereby altering the true value
of current or voltage being measured. Of course there were vacuum tube voltmeters
(VTVM) with high input impedances, but few hobbyists or laymen could afford them.
This piece reports on how the advent of a
non-tube-based rectifier permitted alternating current (AC) measurements to
be made by DC-driven d'Arsonval meter movements so as to not excessively load the
circuit being measured. Rectox meters had the rectification components...
 Amentum is seeking well-qualified candidates
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Team support the Marine Corp Warfighting Lab (MCWL) sponsored projects as an
RF / Spectrum Systems Engineer. In this role you will: Perform RF/Spectrum Engineering
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systems engineering including waveform development, networked systems and transmission
systems deployment. Perform spectrum and frequency management, system design and
verification of system performance. Conduct technical analyses, trade studies, market
research and draft white papers and written reports as required. Perform Systems
Engineering evolutions: Refine system requirements; review requirements traceability
and cross-reference matrices. Develop and review program engineering documentation
(Systems Engineering Plan, Test and Evaluation Master Plan etc.)...
 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...
 With more than 1000
custom-built symbols, this has got to be the most comprehensive set of
Visio
Symbols available for RF, analog, and digital system and schematic drawings!
Every object has been built to fit proportionally on the provided A-, B- and C-size
drawing page templates (or can use your own). Symbols are provided for equipment
racks and test equipment, system block diagrams, conceptual drawings, and schematics.
Unlike previous versions, these are NOT Stencils, but instead are all contained
on tabbed pages within a single Visio document. That puts everything in front of
you in its full glory. Just copy and paste what you need on your drawing. The file
format is XML so everything plays nicely with Visio 2013 and later...
 Since 2003, Bittele Electronics has consistently
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 I believe this is the very first episode
of the highly popular "Mac's
Radio Service Shop." This series of instructive stories was the brainchild of
none other than John T. Frye, creator of the Carl and Jerry series that ran
in Popular Electronics for many years. "Mac's Radio Service Shop" began life in
April 1948 in Radio News magazine (which later became Radio & Television News,
then Electronics World), and changed its name to simply "Mac's Service Shop" until
the final episode was published in a 1977 Popular Electronics magazine. "Mac" is
electronics repair shop owner Mac McGregor, and Barney Jameson his his eager, if
not somewhat naive, technician assistant. "Lessons" are taught in story format with
dialogs between Mac and Barney. Interestingly, here we have Barney on his first
day on the job, and Mac is just now asking him whether he has any experience servicing
electronics gear. Wouldn't you think he would have asked that question prior to
hiring him?
 "Machine learning models
are growing exponentially larger. At the same time, they require exponentially more
energy to train, so that they can accurately process images or text or video. As
the AI community grapples with its environmental impact, some conferences now ask
paper submitters to include information on CO2 emissions. New research offers a
more accurate method for calculating those emissions. It also compares factors that
affect them, and tests two methods for reducing them. Several software packages
estimate the carbon emissions of AI workloads. Recently a team at Université Paris-Saclay
tested a group of these tools to see if they were reliable. 'And they're not reliable
in all contexts,' says Anne-Laure Ligozat, a co-author of that study who was not
involved in the new work. The new approach differs in two respects, says Jesse Dodge,
a research scientist at the Allen Institute for AI and the lead author of the new
paper, which he presented last week at the ACM Conference on Fairness, Accountability,
and Transparency (FAccT)..."
 ConductRF is continually innovating and
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access. Please visit ConductRF today to see how they can help your project!
 Electronic warfare (EW) is a familiar term
today, but in 1947 its use was a relatively new concept. As you know, great advancements
in electronics occurred during the War years - from all the major Allied and Axis
countries involved. Transmitters and receivers, modulation techniques, antenna designs,
transmission lines, component introductions and improvements, ruggedness and portability
features (packaging), reliability, serviceability, operational techniques, and other
aspects of electronics benefitted from that oft-credited "mother of invention" named
"necessity." Along with electronic communication improvements came the need to thwart
the enemy's efforts to exploit those new methods; hence, the term "electronic warfare"
(aka electronic counter-measures, ECM). Now we also have electronic counter-counter-measures
(ECCM) to thwart the thwarting of the enemy. Can ECCCM be far behind?...
 According to this promotion in a 1948 issue
of Radio News magazine, the Howard W. Sams company had published more
than 5,500
Photofact service data packs since beginning in 1938 - that's averaging 550
per year. There would have been many more if not for the cessation of domestic radio
production during the war years from 1942 through the middle of 1945. Once televisions
were being cranked out in huge numbers in the early 1950's, the number of data packets
quickly grew into the tens of thousands (including also phonographs, tape recorders,
and other electronics wonders for the home. In fact, by September of 1949 the magazine's
title was changed to Radio & Television News in order to reflect the
importance of servicing the burgeoning TV industry...
RF Cascade Workbook is the next phase in the evolution of
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using a multi-thousand dollar simulator when a high level system analysis is all
that is needed. An intro video takes you through the main features...
 Windfreak Technologies designs, manufactures,
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to government agencies. Worldwide customers include Europe, Australia, and Asia.
Please contact Windfreak today to learn how they might help you with your current
project.
 Hams like members of the Mogollon Rim Collins
Collectors Club (K0CXX)*, play an important role in the preservation of vintage
radio equipment. They own a nice example of a
Collins model 30K-5 medium power (250 W) AM transmitter that is the subject
of this 1946 article in Radio News. At 5½ feet tall and weighing 350 pounds, the
30K is many times the volume and weight of a modern solid state transmitter (transceiver
+ PA) having the same capability. Its advertised price in 1946 was $1,450, which
is equivalent to $19.9k in 2022 money - obviously not in the affordability range
of your typical amateur radio enthusiast...
 Author Joel Kellogg* published Part 1
of his "SCIF
and Radio Frequency Secured Facility Design" article a bit over a year ago in
the InCompliance website. Now,
Part 2 is available. He states, "In recent years, we've noticed a growing
confusion in the industry over design and performance requirements for sensitive
compartmented information facilities (SCIF). Part 2 of this article is intended
to highlight the significant difference in the performance of radiofrequency (RF)
shielding between facilities designed per ICS/ICD‑705[1] and those intended to meet
NSA 94-106[2] performance requirements. We will also highlight some of the design
and construction methodologies that lead to significant differences in performance.
As noted in Part 1 of this article, there is a common misconception that a SCIF
design utilizing ICS/ICD‑705 construction recommendations will achieve the performance
requirement set forth in NSA 94-106, the NSA standard for RF shielding performance
and testing. Part 1 reviewed the typical construction recommendations identified
in ICS/ICD‑705, recommended materials, and typical installation methodologies used..."
* Anyone else remember "K, E, double-L, O, dougle-GGood,
Kellogg's best to you!"
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 In CONGRESS, July 4, 1776.
The unanimous Declaration
of the thirteen united States of America, When in the Course of human events,
it becomes necessary for one people to dissolve the political bands which have connected
them with another, and to assume among the powers of the earth, the separate and
equal station to which the Laws of Nature and of Nature's God entitle them, a decent
respect to the opinions of mankind requires that they should declare the causes
which impel them to the separation. We hold
these truths to be self-evident, that all men are created equal, that they are endowed
by their Creator with certain unalienable Rights, that among these are Life, Liberty
and the pursuit of Happiness. -- That to secure these rights, Governments are instituted
among Men, deriving their just powers from the consent of the governed, --That whenever
any Form of Government becomes destructive of these ends, it is the Right of the
People to alter or to abolish it, and to institute new Government, laying its foundation
on such principles and organizing its powers in such form, as to them shall seem
most likely to effect their Safety and Happiness. Prudence, indeed, will
dictate that Governments long established should not be changed for light and transient
causes; and accordingly all experience hath shewn, that mankind are more disposed
to suffer, while evils are sufferable, than to right themselves by abolishing the
forms to which they are accustomed. But when a long train of abuses and usurpations,
pursuing invariably the same Object evinces a design to reduce them under absolute
Despotism, it is their right, it is their duty, to throw off such Government, and
to provide new Guards for their future security.--Such has been the patient sufferance
of these Colonies; and such is now the necessity which constrains them to alter
their former Systems of Government. The history of the present King of Great Britain
is a history of repeated injuries and usurpations, all having in direct object the
establishment of an absolute Tyranny over these States. To prove this, let Facts
be submitted to a candid world...
 You are taught early in your electronics
career to be mindful of the tendency for
measurement
equipment to affect the circuit it is measuring, and therefore the indicated
results. In the case of high frequency circuits, even minute amounts of capacitance
and/or inductance can render results utterly unusable, but even in circuits operating
down to D.C. the simple internal resistance of a meter can profoundly affect measurement
accuracy. High impedance circuits are particularly vulnerable to such "loading"
effects by test equipment. For example, consider a circuit being measured (device
under test, aka DUT) that has an impedance of 10 kΩ and the internal resistance
of the VOM is 100 kΩ (see diagram to left). If the open circuit "true" voltage
level is 11 V, then voltage division effected by the 100 kΩ meter in series
with the DUT's 10 kΩ internal resistance would produce a VOM reading of 10 V
(ten elevenths of 11 volts) - clearly incorrect. In the days before FET (field effect
transistor) input multimeters, when most volt-ohm-milliammeters (VOMs) consisted...
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 In these times of communists and Marxists
(and other "-ists") infiltrating high positions of American government and destroying
our hard-won legacy of freedom, compassion, traditional family values, hard work,
and patriotism, this
Independence Day theme crossword puzzle is created to celebrate our heritage
and resist the corrupters. The Cancel Culture mobs will never dissuade our staff
(Melanie and me) here at RF Cafe! Clues with an asterisk (*) are related to the
puzzle's theme. All crossword puzzles use a personally built dictionary of thousands
of words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics,
chemistry, physics, and other technical subjects. As always, this crossword puzzle
contains no names of politicians, mountain ranges, exotic foods or plants, movie
stars, or anything of the sort unless it/he/she is related to this puzzle's technology...
 Life is a constant battle on all fronts,
be it in health, personal relationships, business, medicine, careers, education,
technology, or any other realm. Scientists, engineers, and technicians at the former
Bell Telephone Laboratories are affected by that maxim as well as any group
of people. The company, known to many as Bell Labs, invested a huge amount of funds
and personnel effort into fighting the problems which constantly cropped up both
during research and development and while servicing their massive installed base
of equipment and transmission lines. Bell Labs regularly ran full-page
ads in magazines (including technical and others like Life, The Saturday Evening
Post, Woman's Day, etc.) informing the paying public of the extents they went to
in order to bring new products to market and to keep existing systems providing
excellent quality communications (the best in the world). This example for a 1948
issue of Radio News magazine tells of the unexpected chemistry issues solved by
their crack teams of employees...
 Selenium rectifiers were the first widely
used replacements for vacuum tubes in commercial electronic equipment. Since amplification
was not possible - that came in late 1948 with the invention of the transistor,
compliments of Shockley, Brattain and Bardeen - diode action in AC-DC power supplies
was its primary application. Typical reverse breakdown voltage is in the neighborhood
of 20 volts and current handling capability depends on the interface surface area.
Cost kept the selenium rectifiers from being widely adapted early in their history
(1933), but by 1946 when this article was published in Radio-News magazine
it had dropped enough to make their use economical. Eliminating one or two vacuum
tubes in a radio or television power supply made the sets more efficient and increased
reliability since the selenium rectifiers rarely suffered failures if designed into
the circuit correctly...
 Well I'll be darned, old Mac the master
radio repairman taught me something else new in this October 1949 issue of Radio &
Television News magazine. Along with giving sidekick and trusted technician
Barney a lesson on business ethics and how honest dealing can pay dividends as societal
conditions change, he also put on his Sherlock Holmes cap and deduced a
surprising cause for circuit failure based on the physical location of a lady's
radio; read on to learn the details. As usual, the exact scenarios of the stories
do not apply to today's environment and/or equipment, but the troubleshooting logic
certainly does. And, as usual, the time of year wherein the technodrama takes place
aligns with the edition's month of publication...
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