See Page 1 |
2 |
3 |
4 | of the June 2024 homepage archives.
Friday the 14th
To show how far in advance of publication
date magazines used to need to have their content submitted, this January 1961 issue
of Radio-Electronics noted the fortieth anniversary of the country's first
commercial radio broadcast by
KDKA on November 2, 1920 (two months). KDKA's first daily broadcast began on
September 20, 2021. Also reported was a record 100 mile underground communication
record. Using a buried antenna, it used a new transmission mode that exploits the
interface region between the ground surface and the atmosphere. A new international
standard meter was changed to the length of 1,650,763.73 wavelengths of the orange-red
line of light given out by krypton 86. Since 2019, the meter is defined as the distance
light travels in a vacuum in length of the path travelled by light in vacuum in
1/299792458th of a second, based on a cesium time standard. A color TV standard...
•
ARRL Youth Rally Success at Dayton Hamvention
•
UK Semiconductor Institute Creation
•
More Spectrum to Add $27B to India's GDP
• U.S. Tariffs Prompt
Supply Chain Shift
• IARC Again Asked to
Review RF Cancer Risk
Being that the world's largest RF and microwave
trade show, IMS2024 (International Microwave
Symposium - see
Exhibit
Floor map highlighting RF Cafe sponsors) is happening beginning June 16th in
Washington, D.C., I thought this Dilbert™ comic strip from May 6, 2012, would be
a fitting subject for posting on RF Cafe. Having been to a couple of the IMS shows
and talking to exhibitors, many seem to actually relate to Dilbert's experience.
The main value of having a presence there
is often simply being seen in the realm of major players, which confers a certain
level of industry gravitas. So, even if spending a week at the show does not directly
result in new customers, at least some companies believe the cumulative effect of
a persistent presence will pay off in the long run. At least one major RF/microwave
manufacturer has concluded otherwise...
John Gill published many
electronics-themed crossword puzzles in Electronics World magazine
in the 1950s and 1960s. Unlike the weekly RF Cafe engineering crossword puzzles,
some of the words used herein are not directly related to science, engineering,
mathematics, etc. Some of the words are more particular to the era, but that shouldn't
present too much difficulty. You will find the level of difficulty much less than
that of a Sunday edition New York Times crossword, but there are some challenging
clues, particularly given the era that it was created. Bon chance...
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library. They also provide custom coax solutions for applications where some standard
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It was a lot of work, but I finally finished
a version of the "RF &
Electronics Schematic & Block Diagram Symbols"" that works well with Microsoft
Office™ programs Word™, Excel™, and Power Point™. This is an equivalent of the extensive
set of amplifier, mixer, filter, switch, connector, waveguide, digital, analog,
antenna, and other commonly used symbols for system block diagrams and schematics
created for Visio™. Each of the 1,000+ symbols was exported individually from Visio
in the EMF file format, then imported into Word on a Drawing Canvas. The EMF format
allows an image to be scaled up or down without becoming pixelated, so all the shapes
can be resized in a document and still look good. The imported symbols can also
be UnGrouped into their original constituent parts for editing...
Thursday the 13th
Zener diodes, named after their inventor,
Clarence Zener, were a paradigm-changing introduction to the electronics industry.
At a very low price and parts count, precise and stable voltage sources can be built
for just about any voltage reference level. Zeners are designed to operate in the
breakdown region of the pn junction which is normally avoided with standard rectifier
diodes. That voltage level is predictable and consistent. A standard range of voltages
(2.7 V, 3.0 V, 3.3 V, 3.6 V, 3.9 V...) are manufactured
to satisfy most needs. Notice a familiar pattern there? Yep, they follow the standard
5% tolerance resistor value series. I don't know why that was done - there is no
semiconductor physics reason for it. Just as having a standard 5x10n Ω value
for resistance would be extremely handy, so it would be for a voltage reference,
given the prevalence of 50 Ω for impedances and 5.0 V for digital circuits...
Sam Benzacar, of Anatech Electronics, an
RF and microwave filter company, has published his June 2024 newsletter that, along
with timely news items, features his short op-ed entitled "The
Vital Role of Microwave Technology in Quantum Systems." In it, he discusses
the use of microwave components in quantum computers. I have noticed in the photos
of the quantum computers, suspended by fine cables giving them a golden chandelier
look, that there seems to be lots of small diameter coaxial cable and connectors
plugging into what appears to be standard microwave-like packages. Turns out, according
to Sam, that those are coaxial cables and components like mixers, amplifiers, directional
couplers, circulators and isolators, and of prime interest to him, filters. It all
still seems like black magic, as does aka quantum teleportation and entanglement
(or "spooky action at a distance" as Albert Einstein referred to it)...
When I think back at the engineering labs
from my days in school, I wonder how much things have really changed from then until
now. It is hard to believe that freshman and sophomore labs are not still consumed
with radial lead resistors, inductors, and capacitors, solderless breadboards, and
a variety of light bulbs, motors, transformers, relays, and rheostats. By the time
you move into the junior year, labs have gotten a bit more intense with microprocessor
controls (mine used an 8088 CPU with machine language programming for the serial
port), some high voltage apparati[sic], digital logic circuits (74-series leaded
ICs), and a chance to lay out/fabricate/populate a PCB. On-hand test equipment consists
of 2nd or 3rd generation oscilloscopes, signal generators, and power supplies...
This
tide-predicting machine
was one of many advances he made to maritime tech. "In 1870, William Thomson, mourning
the death of his wife and flush with cash from various patents related to the laying
of the first transatlantic telegraph cable, decided to buy a yacht. His schooner,
the Lalla Rookh, became Thomson's summer home and his base for hosting scientific
parties. It also gave him firsthand experience with the challenge of accurately
predicting tides. Mariners have always been mindful of the tides lest they find
themselves beached on low-lying shoals. Naval admirals guarded tide charts as top-secret
information. Civilizations recognized a relationship between the tides and the moon
early on, but it wasn't until 1687 that Isaac Newton explained how the gravitational
forces of the sun and the moon caused them. Nine decades later, the French astronomer
and mathematician Pierre-Simon Laplace..."
The many idiosyncrasies of atmospheric phenomena
that affect
long distance communications are certainly more well known and understood today
than they were in the early days of radio. Ionization, temperature and pressure
gradients, suspended particulate contamination, and other factors have been extensively
studied, measured, and modeled. Daily and seasonal patterns are somewhat predictable
and exploitable for purposes of general use, but short term variability that affects
long distance radar measures of distance, altitude, and speed requires near instantaneous,
pulse by pulse analysis of atmospheric conditions. Research and development of methods
for accommodating short term variations that skew measurements are an ongoing science.
An extreme example of atmospheric variation compensation is the method used by ground-based
telescopes that shine lasers into the ionosphere to create "artificial stars" whose
scintillation properties can be used in both software and adaptive optics to cancel
out apparent changes in position and intensity...
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...
Alliance Test Equipment sells
used / refurbished test
equipment and offers short- and long-term rentals. They also offer repair, maintenance
and calibration. Prices discounted up to 80% off list price. Agilent/HP, Tektronix,
Anritsu, Fluke, R&S and other major brands. A global organization with ability
to source hard to find equipment through our network of suppliers. Alliance Test
will purchase your excess test equipment in large or small lots. Blog posts offer
advice on application and use of a wide range of test equipment. Please visit Allied
Test Equipment today to see how they can help your project.
Wednesday the 12th
Having been born sometime before around
1970 will make it much more likely that you will be familiar with the scenarios
depicted in these three
electronics-themed comics. They appeared in a 1962 issue of Radio-Electronics
magazine (I colorized them). The comic from page 72 can be applied to to modern
day situations where an owner calls in a repairman after he tinkers around trying
to save some money on a service call, and makes things worse than they were to begin
with, then trying to BS the serviceman into believing he hasn't monkeyed with it.
The page 96 comic is a guy thing - which used to be allowed before tender feeling
were offended by such things. The last one brings back memories of being in the
local convenience store with my father as he is checking the vacuum tubes...
Temwell
is running a 30% Off
sale on it's in-stock line of filters ---
for the entire month of June. Temwell is a manufacturer
of 5G wireless
communications filters for aerospace, satellite communication, AIoT, 5G networking,
IoV, drone, mining transmission, IoT, medical, military, laboratory, transportation,
energy, broadcasting (CATV), and etc. An RF helical bandpass specialist since 1994,
we have posted >5,000 completed spec sheets online for all kinds of RF filters
including helical, cavity, LC, and SMD. Standard highpass, lowpass, bandpass, and
bandstop, as well as duplexer/diplexer, multiplexer. Also RF combiners, splitters,
power dividers, attenuators, circulators, couplers, PA, LNA, and obsolete coil &
inductor solutions...
Here is another instance of an article which,
if it had been in an April magazine issue, you might be justified in thinking it
might be a gag. "FM Carrier Stabilization," a 1946 Radio-Craft feature,
centers around the use of a
General Electric (GE) GL-2H21 "Phasitron" vacuum tube. Be assured that it is
a real component, developed to address the difficulties in achieving frequency modulation
(FM) requirements set forth by the Federal Communications Commission (FCC) at what
was really the dawn of the FM commercial broadcast radio era. Only a little over
a decade had passed since Major Armstrong announced his broadband FM invention,
and radio stations were planning to adopt the superior (to AM) form of broadcasting
at a rapid rate, following the end of World War II. The Phasitron was GE's
solution to the problem of maintaining the average carrier frequency stability requirement...
Empower RF High-Power
S-Band Pulsed Transmitter
Empower RF Systems, the technology leading
provider of high-performance RF amplifiers, is proud to announce the launch of the
Model 2254 S-Band Pulsed Transmitter. This air-cooled, high-power transmitter
operates from 2900 to 3500MHz and is designed to meet the demanding requirements
of radar and electronic warfare applications. The Model 2254 boasts an impressive
peak power output of 15kW peak power, making it one of the most powerful S-band
transmitters in its class. With a duty cycles up to 20% and pulse widths up to 500
micro seconds, this transmitter is capable of delivering sustained high-power pulses
for extended periods, ensuring reliable performance in mission-critical scenarios.
This transmitter combines cutting-edge technology with robust design, delivering
unparalleled performance and reliability for our customers' most challenging applications
in radar, electronic warfare and directed energy research.
Charles Babbage's 19th century Difference
Engine might be considered the beginning of complex mechanical calculators' use
in science and engineering. It really was not all that long ago. Massive single-purpose
analog computers were designed and constructed in the middle of the last century
for calculating, among other things, projectile trajectories, multi-body orbits,
electrical circuit functions, nuclear detonations, calculation of mathematical function
tables, and navigation. Eventually electrical computers joined the arsenal of tools
available to significantly reduce the amount of time required to carry out complex
calculations requiring multiple iterations using a range of input variables. Programmable
vacuum tube and then transistorized digital computers expanded the range of applications,
but recall that even by the early 1960s, during the early manned space flight projects...
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...
Tuesday the 11th
An incredibly glaring example of the famous
admonishment* that those who ignore history are condemned to repeat it, Radio-Craft
magazine editor Hugo Gernsback wrote in May of 1941, a full half year before the
United States of America officially entered World War II, about how current
conditions regarding domestic commercial radio broadcast stations were likely being
used by German agents to send coded messages to offshore vessels (ships, submarines,
and aircraft). In example, he cited, amazingly, an article he himself published
in 1915 in The Electrical Experimenter magazine accusing Dr. K. G. Frank,
of the German Telefunken company, of
conducting
spy operations from the Sayville, NY, station on Long Island. A copy of the
letters that were exchanged between Mr. Gernsback and Dr. Frank were reprinted
in this edition (see "Sayville Once More"). Spoiler alert in case you don't read
the other article: Dr. Frank was eventually arrested for his espionage activities
and interred for the duration of WWI...
"Say again." That phrase is heard often
in telephony conversations both wired and wireless. It was coined near the end of
World War II by Air Corpsman 2nd Lt. Byron A. Susan, as reported in the
January 1945 edition of Radio Craft magazine. Lt. Susan was responsible
for setting standards for "radio
phraseology" to eliminate ambiguity between aviators and ground forces. "Say
again" replaced "Repeat" because the latter is an artillery term used to order another
round of assault from a gun salvo. The history of the confirmation "Roger" is murky,
but many agree it comes from the older military phonetic pronunciation of the letter
"R" being "Roger," and in radio the letter "R" meaning "received." Another common
bit of radio phraseology is "Wilco," which is a contraction of the words "will comply..."
Today, typing in Chinese works by converting
QWERTY keystrokes into Chinese
characters via a software interface, known as an input method editor. But this
was not always the case. Thomas S. Mullaney's new book,
The Chinese Computer: A Global
History of the Information Age, published by the MIT Press, unearths the
forgotten history of Chinese input in the 20th century. In this article, which was
adapted from an excerpt of the book, he details the varied Chinese input systems
of the 1960s and '70s that renounced QWERTY altogether. 'THIS WILL DESTROY CHINA
forever,' a young Taiwanese cadet thought as he sat in rapt attention. The renowned
historian Arnold J. Toynbee was on stage, delivering a lecture at Washington and
Lee University..."
Robert Gary waxes philosophical on the subject
of ground in his Electronics World magazine article, "'Grounds'
for Confusion." He is justified from the viewpoint of someone attempting to
make sense of how something as seemingly fundamental as Earth ground is not a constant.
The layman probably doesn't care. Practitioners in the electrical and electronics
realms who deal only with low frequencies and short distances might occasionally
be affected by differences in ground potentials, although they might not realize
it is the cause of their problems. Those with more than a casual involvement (designers,
installers, and maintainers as opposed to only users) in high frequencies and/or
long distance signal interconnections are likely to be intimately familiar with
the effects of ground potential differences...
Banner Ads are rotated in all locations
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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
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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...
Monday the 10th
When this News Briefs column appeared in
a 1962 issue of Radio-Electronics magazine, solid state infrared (IR) detectors
were still a relatively new technology, and integrated circuits had not entered
the commercial marketplace. Developing an
IR orientation sensor compact enough to fit a pair of them (azimuth and altitude
sensing) into an orbiting surveillance platform was quite a feat. A phased array
could not be made small enough, so a rotating angled mirror was used for steering
- reminiscent of the early electromechanical television scanning systems. Also reported,
among other things, were a new ruby laser, fraudulent color TV tube claims, and
more women entering the engineering and science fields...
For some reason the subject of grounding
has been very prominent in my reading in the last few days. The chapter I just finished
reading in one of David Herres' books on the National Electric Code (NEC)
covering grounding of commercial and residential services, an article by H. Ward
Silver in QST titled, "Grounding and Bonding Systems," and now this article
by John T. Frye (of Carl and Jerry fame) on grounding, makes for a wealth of
knowledge. Mr. Frye takes a unique approach at teaching by exploiting his gift for
story-telling. In this article, electronics repair shop owner Mac McGregor gives
technician Barney a nice bit of tutelage on
what constitutes a good Earth ground and what does not. In some environments,
treating the soil with an electrically conductive substance...
Axiom Test Equipment, an electronic test
equipment rental and sales company has published a new blog post that covers how
temperature calibration baths provide a dependable means of calibrating temperature
sensors of different shapes and sizes, with capabilities of many at one time. Often
simply called calibration baths,
temperature calibration baths are not just tanks for temperature-controlled
fluids. They are integrated systems consisting of a stainless-steel tank, a condensing
coil and cooling plate, a heater, propeller, and stirring motor. These components
combine to maintain selected fluids within the tank at tightly controlled temperatures
across a wide temperature range. When evaluating temperature calibration baths,
parameters for comparison include the volume, size, and weight of the bath, its
total temperature range, power consumption, heating and cooling times...
Biographical historians spend endless hours
searching old media for bits of information on their subjects. Finding useful material
on more renowned personalities is not a problem, but filtering out relevant bits
for a particular theme can be daunting. On the other hand, finding useful information
on lesser known people can be frustrating because there is so little information
readily available. Great Britain's World War II era superstar
Winston Churchill undoubtedly falls into the former category. While scanning
through my many vintage electronics and science magazines for interesting fodder
to post on RF Cafe, I'm always on the lookout for cameo appearances like this one
of Prime Minister Churchill talking on a walkie-talkie (aka "handie-talkie" at the
time)...
SF Circuits' specialty is in the complex,
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PCB production that is outside the capabilities of normal circuit board providers.
Please take a moment to visit San Francisco Circuits today. "Printed Circuit Fabrication &
Assembly with No Limit on Technology or Quantity."
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...
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.
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