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4 of the May 2024 homepage archives. Tuesday the 21st
 In his spare time, when not developing world-changing
concepts of information theory, Claude Shannon designed this
Minivac 601 programmable computer for students and hobbyists. It had 6
bits of data storage, implemented with electromechanical relays. Its output consisted
of six incandescent lamps. Marketed by Scientific Development Corporation, advertisements
for it appeared in magazines like Popular Science in the early 1960s. $85 in 1961
is the equivalent of around $885 today per the BLS CPI calculator, which is about
what high end smartphones cost today. Since this ad is pitching a computer, let
us perform a few simple calculations. Inflation from 1961 through 2024 represents
a factor of 10.4 in 63 years, an average of 0.165x per year. Four short years ago
the equivalent price was $731, representing a factor of 8.6 in 59 years, an average
of 0.146x per year. Continuing, 0.165/yr ÷ 0.146/yr = 1.12, or a 12% increase
in the last four years...
 Not everyone who visits websites such as
RF Cafe is a seasoned electronics veteran. While I and most likely you, too, can
do series and parallel circuit analysis (and series/parallel for that matter, possibly
using Fourier or La Place transforms for reactive AC circuits) in our sleep,
many are recently getting into the wonderful world of electronics who are just coming
of age or have suddenly at a later point in life developed a passion for the science.
Accordingly, this article from a 1932 issue of Radio News magazine provides yet
another tutorial on the fundamentals of series and parallel circuit analysis. Only
resistors and basic Ohms law are covered. Don't let the vacuum tube schematic symbols
deter you.
 "5G communications technology has been overhyped
but
6G may live up to the revolutionary promise that its predecessor did not, a
British expert told a leading tech conference in China. Jiangzhou Wang, a professor
at the University of Kent’s school of engineering, told a technology conference
in Beijing on Friday that 5G had yet to result in a killer app. 'I am objectively
disappointed with 5G,' Shanghai-based financial news site Yicai quoted Wang as saying
at the Sohu Annual Sci-Tech Conference. 'In the 5G era, we have not seen a blockbuster
application for ordinary consumers, nor has it been widely applied in vertical industries.'
Future 6G technology might be revolutionary rather than incremental. '5G has been
overhyped, as if it can do everything..."
 When
LEGO blocks were first
introduced in their current form in Denmark in the late1940s, founder Godfred Kirk
Christiansen could not have imagined how wildly popular his "toy" would become with
sculptors. That generations of kids would while away hours at a time building original
and predesigned structures per printed instructions were his realized dream, Godfred
would be in awe over how his creation has been applied from professional and amateur
artists. By the way, LEGO is a contraction conceived of by Christiansen from the
Danish phrase "leg godt," meaning "play well." The June 2012 issue of Scientific
American magazine has an article titled "Fusion's Missing Pieces" on the current
state of nuclear fusion, and with it is a photo of a cut-away view of a tokomak...
 If
subjects pertaining to electronics - particularly vacuum tubes - are like music
to your ears, then this poem entitled "What Is It?," from
the February 1943 edition of QST magazine, should suit you just fine. The
rhyming words are supplied by author Frank Judd; you just need to supply the harmony.
You might recognize paraphrasing of other familiar works such as Longfellow's "Paul
Revere's Ride." Poems like this one were actually quite common back in the day.
In fact if you look through the list of articles that I have posted from vintage
QSTs, you will find about a dozen...
 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...
Monday the 20th
 Maybe the term "time
domain reflectometery" had not been coined when this Bell Telephone Laboratories
(Bell Labs) advertisement appeared in a 1948 issue of Popular Science magazine.
Or, maybe the creators figured Popular Science readers, while generally a more technically-oriented
group, might not possess the depth of understanding needed to appreciate the phrase.
At the time, use of coaxial cable transmission lines for carrying telephone calls
was fairly new, although Bell began using some coaxial cable in 1927. A decade earlier,
prior to great advances in high frequency communications during World War II,
twisted pairs of solid conductors were sufficient to handle traffic. They did a
good job, but each twisted pair carried only a single circuit operating at audio
frequencies. That is why telephone cables were so large in diameter - they could
be holding hundreds of twisted pairs. Coaxial cable signals can handle hundred or
thousands of channels by modulating across a very wide bandwidth...
 You've
seen photos of
airplane
boneyards in the desert where retired commercial and military planes are stored
for use in cannibalization of replacement parts. A desert environment is ideal because
corrosion from water is minimal. Did you know there are also
wind turbine graveyards? One of the largest is located in Sweetwater, Texas.
Most of what is stored there are the fiberglass and carbon fiber blades, cut into
pieces for easier handling. Unlike the airplanes whose wing parts in time may serve
a purpose, these wind turbine "wings" (that's what they are) will likely remain
there forever. Some companies promise to recycle expired blades, but few ever do.
EV battery pack boneyards probably also exist, but you'll never see a picture of
one because political concerns will assure they are well hidden from public view
(probably in a 3rd world country where child labor is used to process them).
 It's probably a safe bet that most people,
even at the
dawn of color television, knew of the competition which occurred for the adoption
of three different methods of implementation. Two of them - line-sequential by Color
Television, Inc. (CTI), and dot-sequential by Radio Corporation of America (RCA)
- were fully electronic while the third system by the Columbia Broadcast System
(CBS) used a kludge of a spinning color wheel placed in front of a black and white
display. The CBS field-sequential design used a synchronization component of the
composite transmitted signal to position the correct color screen (red, yellow,
or blue) in front of the screen as the electron gun scanned the CRT - analogous
to how World War I airplane machine guns were synchronized with the engine
to fire between propeller blades. Of course an out-of-synch scenario in the color
wheel was not as serious as with the machine gun...
 As the general election approaches here
in the U.S., more attention is being paid to voting legitimacy, particularly by
non-citizens. This was very recently brought to light:
18 U.S. Code § 611
- Voting by aliens --- "(a) It shall be unlawful for any alien to vote
in any election held solely or in part for the purpose of electing a candidate for
the office of President, Vice President, ... Member of the Senate, Member of the
House of Representatives, ... unless ---
(c) Subsection (a) does not apply to an alien if --- (3)
the alien reasonaly believed at the time of voting
in violation of such subsection that he or she was a citizen of the United States."
Undoubtedly the millions who have crossed into the U.S. have been instructed to
claim such an exemption. Your vote can be nullified by an illegal alien with this.
Undoubtedly the millions who have crossed into the U.S. have been instructed to
claim such an exemption. Your vote can be nullified by an illegal alien with this.
 Radio control (R/C) of a model doesn't get
much simpler than the transmitter and receiver circuits shown in the schematics
of Figure 2. Of course the cleanness of the transmitted signal and the selectivity
of the receiver of that signal leaves a lot to be desired. In 1952 when this article
appeared in Radio & Television News magazine, the airwaves weren't cluttered
with wireless communications devices, but given that these radio systems were sharing
the electromagnetic spectrum with Citizens Band (CB) radio, the chances of getting
"shot down" from nearby operators was pretty high if you lived within a few miles
of where CB'ers were communicating. More sophisticated R/C equipment was available
from commercial manufacturers, but this system targeted the do-it-yourself types
and those with limited hobby budgets. A lot of airplane models which consumed many
hours and dollars of a flyer's resources met with their demise as the result of
a stray signal blocking...
RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running
series, RF Cascade Workbook. Chances are you have never used a spreadsheet
quite like this (click
here for screen capture). It is a full-featured RF system cascade parameter
and frequency planner that includes filters and mixers for a mere $45. Built in
MS Excel, using RF Cascade Workbook is a cinch and the format
is entirely customizable. It is significantly easier and faster than using a multi-thousand
dollar simulator when a high level system analysis is all that is needed...
Friday the 17th
 Dig those crazy curved pistons, man. They
are righteous! That was the sort of hip lingo just beginning to hit the scene in
1961 when this "Rotary
Engine Fires Like a Six-Shooter" article appeared in Popular Science
magazine. It was not a Wankel type rotary engine in that it still used pistons and
connecting rods like a traditional internal combustion engine (ICE). Looking as
surreal as the watches in Salvador Dali's "The Persistence of Memory" painting,
the pistons' shape conforms to the arched cylinder in which it reciprocates a few
thousand times per minute. How someone thinks up a scheme like this is beyond me.
It took a couple readings to truly get a grasp on the operation. The writer is a
bit misleading when asserting that the pistons are not really reciprocating in the
cylinders, but in fact they are; they are just not driven by the traditional crankshaft.
The engine's configuration reminds me of a modern brushless motor where the armature
remains fixed and the field...
 Every once in a while having your own website
pays off by having someone offer hard- or difficult-to-find information. Back in
2016 when I originally posted the Radio Service Data Sheet (RSDS) for the Columbia
Screen-Grid 8 (SG-8) Receiver, no photo could be found online. Notice hugeness of
the components on top of the electronics chassis - the vacuum tubes, the metal shields,
the transformers, the coils, etc. I always put in a fair amount of effort to find
actual pictures of the radios. An image search usually does the job, but sometimes
there is nothing to be found. This RSDS appeared in the October 1930 issue of
Radio-Craft magazine. Typical of the era is a very ornate wooden chassis,
and note the tiny tuning window in the center - no round dial or linear frequency
scale...
 According to Electronics magazine
editor Lewis Young in mid-1964, the industry was entering into a
slump in business opportunities. The boom times provided during the war years
of WWII and Korea had resulted in, according to Mr. Young, a lax attitude toward
operational strategy that led to wasteful spending and poor accountability for project
results. It wasn't just the defense contractors' fault because government bureaucrats
- from relatively low ranking military personnel to elected lawmakers - had (have)
a habit of making sudden changes to contract requirements. Maintaining the resources
needed to keep up with ever-evolving demands necessitated a lot of the excess. Fortunately,
the military-industrial complex, as President Dwight D. Eisenhower dubbed it,
was on the verge of being thrown another huge monetary bone - the Vietnam War. President
Kennedy was already pumping lots of equipment and manpower into it, and LBJ would
follow suit with vigor. The money pipeline was filling up quickly; the electronics
industry was to be saved once again...
 "The
Radio
Access Network (RAN) market is "still struggling," according to the latest report
from telecom analysts Dell'Oro Group. The first quarter of 2024 saw exceptionally
weak results, with a decline of 15-30% in the overall global RAN market - the steepest
decline since Dell'Oro started covering this market in 2000, according to Stefan
Pongratz, Dell'Oro VP and analyst. Dell'Oro measures the sector by both revenue
and units sold, but "the focus is on revenue," Pongratz said. Huawei, Ericsson,
Nokia, ZTE and Samsung are the top five RAN suppliers, based on worldwide revenues.
The vendors' positions remained stable but 'there have been shifts in vendor shares,'
Dell'Oro said in an email. 'Huawei's 4QT revenue share improved relative to 2023,
while Nokia lost ground over the same period.' So, we can look forward to dour first-quarter
results from our Nordic friends at Nokia and Ericsson, following disappointing fourth-quarter
results. Ericsson said that it would cut 1,200 Swedish staff in March 2024. This
follows planned cuts of 8,500 people worldwide..."
 I'm old enough to remember the
1973 Oil Crisis era (the subject of Mac McGregor's and Barney's discussion)
that resulted from an oil embargo instituted by Arab oil producing nations during
the Yom Kippur War where Egypt and Syria launched a surprise attack on Israel. I
didn't get my driver's license until Fall of 1974 (turned 16 on August 18th), so
the worst of it was pretty much over by then. However, I clearly remember sitting
in long lines at the gas station with my father, and then being limited in the amount
that could be purchased (i.e., no fill-ups). Gas prices jumped from a national average
of 38.5¢/gallon in May 1973 to 55.1¢/gallon in June 1974 (43% increase in a year).
According to the BLS' Inflation Calculator, that is the equivalent of about $3.52/gallon
in 2024 money. That's about what gas is costing right now, so today we're paying
oil embargo era rates (thank you Brandon). If you were fortunate enough to own a
boat during those times...
 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...
 Empower RF Systems is the technological
leader in RF & microwave power amplifier solutions for EW, Radar, Satcom, Threat
Simulation, Communications, and Product Testing. Our air and liquid cooled amplifiers
incorporate the latest semiconductor and power combining technologies and with a
patented architecture we build the most sophisticated and flexible COTS system amplifiers
in the world. Solutions range from tens of watts to hundreds of kilowatts and includes
basic PA modules to scalable rack systems.
Thursday the 16th
 From the 1940s through the 1980s,
National Radio Institute (NRI) ran full-page and multi-page advertisements in
many electronics and technology magazines, including Popular Mechanics,
Radio News, and here in this 1947 issue of Popular Science. I
don't recall exactly how/where I learned of the NRI when I enrolled in their "Electronic
Design Technology" course, circa 1987. At the time I was working as an electronics
technician for Simmonds Precision Instruments in Vergennes, Vermont. That was immediately
preceding my completing a Bachelor of Science degree in Electrical Engineering at
the University of Vermont. My formal training in electronics began in the U.S. Air
Force while attending technical school at Keesler AFB, Mississippi, for being an
Air Traffic Control Radar Repairman. NRI president J. E. (James Ernest) Smith,
whose face appeared regularly in the ads...
 British engineer John Sargrove was to the
production of radios what Henry Ford was to automobiles. At the time this "Robot
Makes Radios" article appeared in a 1947 issue of Radio-Craft magazine,
Sargrove had recently put his
Electronic Circuit Making Equipment (ECME) fully automated assembly line into
operation. Applying knowledge from two decades of developing methods of creating
inductors, capacitors, resistors, and interconnecting conductors using controlled
deposition of various materials on flat substrates, he was able to build 2-tube
AC/DC radios at a rate of up to three per minute, with only two ECME operators -
one at the input and one at the output. The only manual assembly required was the
installation of a potentiometer-switch, a transformer, speaker, and a power cord,
plus joining the two fabricated Bakelite plates together. You will be amazed at
what Mr. Sargrove's machine did. Unfortunately, raw material shortages after
a grueling war...
 "Whether its lobbying in favor in the industry
it represents, ensuring that public policies are promoting innovation or helping
to unite all players in the space, the Semiconductor Industry Association (SIA)
works tirelessly to support the U.S. semiconductor industry. The group also has
its finger on the pulse of the domestic chip manufacturing sector, which it now
says is on track to
triple in size by 2032. In their new Emerging Resilience in the Semiconductor
Supply Chain report, SIA and Boston Consulting Group paint the picture of a sector
that’s shaken off the negative impacts of the global pandemic and great chip shortage,
and that’s well positioned to thrive and expand over the next eight years. Government
funding will play a key role in that expansion. The US CHIPS Act, signed into law
in August 2022, committed $39 billion in grants and loans for semiconductor manufacturing..."
 Transistor basics have not changed since
they were first introduced to the market around 1953, when this issue of QST
magazine reported on them. The first available transistors used germanium substrates,
and then in 1954 Texas Instruments introduced the first commercial silicon transistor.
The hybrid pi equivalent circuit for a PN junction transistor used in modern circuit
simulators has many more "virtual" components in it that allow for high frequency
and nonlinear operation modeling, but for audio and AM type that operates entirely
within the linear region, the equivalent circuit presented in Figure 1 will
still get the job done. Common-(aka grounded-) emitter, common-base, and common-collector
circuits are discussed. I remember in college in the mid 1980s running SPICE simulations
on an IBM XT computer where the transistor model...
 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 280,000 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...
 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. We have >500,000 RF and Microwave passive
components we can ship you today! We offer Quality Precision Parts, Competitive
Pricing, Easy Shopping, Fast Delivery. We're happy to provide custom parts, such
as custom cables and adapters, to fit your needs. Centric RF is currently seeking
distributors, so please contact us if interested. Visit Centric RF today.
Wednesday the 15th
 "Do it with <fill in the blank>,"
was a popular form of saying back in the 1960s and 70s. It is a form of double entendre,
so people thought it was clever. I never did. This "Do It With Diodes" article from
a 1961 issue of Radio Electronics magazine is an example. The term "diode"
was not new to the electronics field at the time, as vacuum tube diodes and selenium
rectifiers had been around for half a century. However, the newfangled semiconductor
form of diodes were just coming on the scene. Germanium and silicon were the compounds
available for commercial devices. More exotic materials were still in research laboratories.
Author Donald Stoner provides a layman's level introduction to semiconductor diode
fabrication and operation. Voltage, current, and power handling capacity was still
fairly low. Prices for common diode types had dropped to a point that were making
them competitive options...
 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
filters have been announced for May 2024 - a 5520 to 5540 MHz cavity bandpass
filter with a passband insertion loss of 1.75 dB and ripple of <0.2 dB,
a 4755 to 5000 MHz cavity bandpass filter with a minimum passband return loss
of 15 dB, and a 4395 to 4955 MHz cavity bandpass filter with a minimum
rejection of 35 dB at 4295 MHz and 80 dB at 5250 MHz. Custom
RF power filter and directional couplers designs can be designed and produced...
 Good, clean humor has always been a welcome
addition to my day whether it comes in the form of a printed comic strip, a TV show,
or someone's mouth. My father's side of the family was populated with many jokesters
who could be counted on to deliver an ad hoc pun or zinger at the appropriate moment.
The environment instilled a great appreciation for such entertainment, so these
electronics-themed comics that appeared in editions of trade and hobby magazines
like Radio-Electronics, Popular Electronics, et al, are a refreshing
distraction from the workaday world. An old saying claims "laughter is the best
medicine*," and while it cannot cure cancer, a good dose of humor often helps ease
the pain...
 "A
recent Bluetooth connection between a device on Earth and a satellite in orbit signals
a potential new space race - this time, for global location-tracking networks. Seattle-based
startup Hubble Network announced today that it had a letter of understanding with
San Francisco-based startup Life360 to develop a global, satellite-based Internet
of Things (IoT) tracking system. The announcement follows on the heels of a 29 April
announcement from Hubble Network that it had established the first
Bluetooth connection between
a device on Earth and a satellite. The pair of announcements sets the stage
for an IoT tracking system that aims to rival Apple's AirTags, Samsung's Galaxy
SmartTag2, and the Cube GPS Tracker. Bluetooth, the wireless technology that connects
home speakers..."
 Here in one short editorial article, Hugo
Gernsback outlines the application of shortwaves in "the next war" to maintain
wireless surveillance of the airspace over towns and cities via what is essentially
radar, to detonate explosive devices by means of a powerful "special combination
impulse," and long-distance wireless communications via radios "so small that one
man can easily carry it." This might seem rather moot in today's world, but in 1935
when this issue of Short Wave Craft magazine went to press, it required
a certain amount of knowledge of wireless communications and a vision regarding
its potential. In my readings of a great many early- to mid-20th-century technical
articles on electronics, aeronautics, physics, etc., it is interesting to notice
how authors of the pre-WWII era referred to what we now call "World War I"
as simply "the World War..."
RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running
series, RF Cascade Workbook. Chances are you have never used a spreadsheet
quite like this (click
here for screen capture). It is a full-featured RF system cascade parameter
and frequency planner that includes filters and mixers for a mere $45. Built in
MS Excel, using RF Cascade Workbook is a cinch and the format
is entirely customizable. It is significantly easier and faster than using a multi-thousand
dollar simulator when a high level system analysis is all that is needed...
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
About RF Cafe.
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