Today in Science History -
Digital Engineering themed crossword puzzle for May 29th, 2022, is brought to
you by RF Cafe. Clues for words relevant to the theme are marked with asterisks
(*). I do believe this is the first digital electronics crossword I have ever made.
All RF Cafe crossword puzzles are custom made by me, Kirt Blattenberger, and
have only words and clues related to RF, microwave, and mm-wave engineering, optics,
mathematics, chemistry, physics, and other technical subjects. As always, this crossword
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
theme (e.g., Reginald Denny or the Tunguska event in Siberia). The technically inclined
cruciverbalists amongst us will appreciate the effort. Enjoy!
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 or
so 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. Check them out!
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.
Atomic energy research came to the forefront
of public awareness in 1945 following the detonation of the world's first nuclear
bombs. X-rays had been studied for decades and uses had been developed for medical
and industrial inspection purposes, but the harmful effects of low level exposure
over long periods of time were still largely undetermined. Some people, like the
author of this report from a 1949 edition of Radio & Television News
magazine, believed "man's life is shortened by exposure to any amount of
radioactivity." That was a rather extreme and alarmist statement to make in
an article whose purpose was ostensibly to encourage engineers, scientists, and
technicians to seek careers in the radio-electronics-nucleonics field...
Power beaming is one of those things I view
as useful for hard to access installations, but very inefficient for anything other
than low power applications. This article in IEEE's Spectrum magazine provides some
insight into the state of the art. "Wires have a lot going for them when it comes
to moving electric power around, but they have their drawbacks too. Who, after all,
hasn't tired of having to plug in and unplug their phone and other rechargeable
gizmos? It's a nuisance. Wires also challenge electric utilities: These companies
must take pains to boost the voltage they apply to their transmission cables to
very high values to avoid dissipating most of the power along the way. And when
it comes to powering public transportation, including electric trains and trams,
wires need to be used in tandem with rolling or sliding contacts, which are troublesome
to maintain, can spark, and in some settings will generate problematic contaminants.
Many people are hungry for solutions to these issues - witness the widespread adoption
over the past decade of wireless charging..."
Don't let the title fool you. This is not
routine" being provided to Barney by his boss, Mac. It turns out to be a brief
introduction into the fine art of troubleshooting intermittent problems in radio
and television circuits. As is usually the case, while the specifics of the scenarios
Mac describes might not apply to your challenge at hand, the general philosophy
always does. It is basically the old process of elimination where after rapping
components mechanically and/or heating or cooling them in hopes of observing a tell-tale
change in performance, the next step is to divide the suspected circuit portion
in half (electrically, but sometimes also physically) and look in one direction.
If the problem isn't there, then divide the circuit in the other direction in half
and go there. Repeat until the problem is found. One of my personal favorite first
steps is to verify all mechanical connector interfaces (if any) are contacting properly.
Clean with alcohol if possible, and burnish with sandpaper if appropriate, then
plug and unplug the connections a few times, just to make sure proper seating...
Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his May 2022 newsletter that
features his short op−ed entitled "This Will Be the Year That Matter, Matters,"
where he describes how "Matter," which was formerly called Project CHIP (Connected
Home over IP) and then Connectivity Standards Alliance (CSA), was announced in December
2019 with the goal of reducing fragmentation and eliminate interoperability issues
with home automation. As with Wi-Fi and Bluetooth, Matter aims to assure compatibility
between systems and devices of all manufacturers. Also in the news is the ongoing
saga of C-Band cell service and radar altimeter interference, "Smart Agriculture"
revenue projections, and rectenna RF energy harvesting...
Some of the earliest television display
schemes were mechanically scanned light projection systems rather than electronically
raster scanned cathode ray tubes. This 1930 vintage article from Radio News
magazine reports on a scheme developed by Arthur Watson whereby a specially formed
rotating Monel disk served as the rotating reflecting surface to produce the light
scanning action. This invention was hailed as a breakthrough that would finally
make commercial TV available to the masses.
Mechanical televisions worked by transmitting scanned images of the original
subject in the form of amplitude modulated electrical signals whose voltage was
determined by the level of reflected light. A synchronizing signal was included
in the transmitted data stream. The scan disk on the receiving end rotated at the
same rate as the transmitter scanning disk, and an electric lamp's brightness was
varied according to the signal's picture voltage level...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
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 (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1
scale so that measurements can be made directly using Visio built-in dimensioning
objects. Page templates are provided with a preset scale (changeable) for a good
presentation that can incorporate all provided symbols...
RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
component supplier. RF coaxial connectors & adapters, coaxial cable &
cable assemblies, surge protectors, attenuators. Items added daily. Free shipping
on orders over $25. We're leading the way again!
ultrasonic communications has not proved to be a reasonable means of transmitting
information from one location to another - even over fairly short distances - is
borne out by the obvious lack of such systems today. With all the technology available
in the form of electronics, mechanics, and software, if it were possible to efficiently
and effectively implement systems of ultrasonic communications, such devices would
be as common as the current plethora of wireless systems. Some early research efforts
at ultrasonic communications were published in a 1945 edition of Radio News
magazine. Regardless of the era, the electromagnetic frequency bands are always
deemed to be too crowded so researchers constantly look for other transmission media.
There is one revolutionary new potential form of remote communications on the horizon:
quantum entanglement. Still largely an enigma, entanglement communications exploits
an observed property of some subatomic particles to be inextricably linked to each
other with no discernable medium or known mechanism...
Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products
such as RF signal generators, RF synthesizers, RF power detectors, mixers, up /
downconverters. Since the conception of WFT, we have introduced products that have
been purchased by a wide range of customers, from hobbyists to education facilities
to government agencies. Worldwide customers include Europe, Australia, and Asia.
Please contact Windfreak today to learn how they might help you with your current
This is very cool if you have an interest
in the early developments in television. I have posted many articles from vintage
electronics magazines documents in the
evolution of color TV. This piece entitled "Print an Arduino-Powered Color Mechanical
Television" appeared on the IEEE Spectrum website. It begins: "Before
flat screens, before even cathode-ray tubes, people watched television programs
at home thanks to the Nipkow
disk. Ninety years ago in places like England and Germany, broadcasters transmitted
to commercially produced black-and-white electromechanical television sets, such
as the Baird Televisor, that used these disks to produce moving images. This early
programming established many of the formats we take for granted today, such as variety
shows and outside broadcasts. The size and weight of a Nipkow disk makes a display
with more than a few dozen scan lines impracticable (in stark contrast to modern
screens with thousands of lines). But when a mechanical TV is fed a moving image,
the result is surprisingly watchable..."
1945 or 2022? Seventy-seven years have passed
since this photo of a
vacuum tube manufacturing facility in China was taken. Given that most new vacuum
tubes are made in China, and that the labor work conditions have not changed much
in the intervening time period (except in high-profile plants like Foxconn where
Apple products are made), this might very likely represent a modern day operation.
BTW, most of the vacuum tubes not being made in China are made in Russia... to assure
their antiquated infrastructure has an ample supple of replacement parts. I say
that only partly in jest. The largest market for new vacuum tubes is music amplifier
equipment and a few commercially made vintage radio replicas (like the Tesslor Model
R601S). BTW, Western Electric (the telephone manufacturer for Bell, back in the
day) is now manufacturing vacuum tubes again...
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 2018 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. An intro video takes you through the main features...
Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave
filters, diplexers, and sub-assemblies. They offer the generally known tubular,
LC, cavity, and waveguide designs, as well as state of the art high performance
suspended substrate models. Through a continuous process of research and development,
they have established a full line of filters of filters of all types - lowpass,
highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact
Reactel today to see how they might help your project.
The August 1972 issue of Popular Electronics
included a short quiz by William Shippee titled "Test
Your Knowledge of Semiconductors." I guessed wrong on question #2, but guessed
right by process of elimination on question #8 (although afterward I discovered
that in 2012 I had posted an article about the #8 device in Electronics World
magazine). Go ahead and take your best shot. You might be surprised at how much
you've forgotten if you don't work with transistors on a regular basis. I'll bet
Q2 has most people guessing, too...
sub-milliohm chips as a separate class of component is a smart strategy that
helps solve associated design challenges. Part 2 of this series features strategies
for verification of the ohmic value of unmounted components and critical assembly.
The growing use of sub-milliohm chip resistors for current sensing creates a spectrum
of challenges for the designer and the process engineer. The component format should
first be selected to support the chosen thermal-management approach, with metal-element
flat chip resistors having two terminals being the most cost-effective solution.
It's then essential to design the PCB tracks and pads to meet the needs of Kelvin
connection, heat dissipation, and avoidance of induced noise..."
I signed up as a "Heath Insider" about a
year ago when news first broke about Heathkit's intention to finally, after a couple
decade hiatus, begin producing built-it-yourself electronics kits again. The Explorer Jr.™
is a basic capacitor-tuned AM radio kit that comes complete with everything needed
to build it. Why not a digitally tuned synthesizer with an LCD display? Company
president Andy Cromarty promises many more kits to follow, with all being in the
classic Heathkit tradition of high quality parts and well-written, illustrated,
step-by-step instructions. It will be a continuation of their "You Can Build It.
We won't let you fail." motto. Since originally posting this page in 2015, Heathkit
has been making slow but steady progress with expanding their line of build-it-yourself
projects. They also now have a cool T-shirt design showing an exploded view of their
"Most Reliable Clock™" model GC-1006, with the proclamation "Heathkit's
Back. It's About Time."
The ARRL (American Radio Relay League) might
be considered as one of the first app developers. At 50¢ and $1 per app, the price
was in-line with one of today's typical not-for-free Apple or Android app. A user
willing to shell out $4 for all six had at his fingertips calculators and reference
tables for capacitive and inductive reactance, resonant frequency, gain and power,
conductor amperage, transformer turns ratio, resistor, capacitor, and inductor series
and parallel combination, and other values. These six apps, dubbed "Lightning Calculators,"
were comprised of bit of cardboard, plastic, and a metal eyelet, not data bits.
Here is a for-real Type B "Lightning Calculator," graciously provided by Joseph
Repair service businesses have always gotten
a bad rap for deliberately inflating part and labor costs - often deservingly so
- but it's a shame the honest brokers are dragged down by the scum (or "gyps" as
this article calls them). Come to think of it, the word "gyp" is likely short for
"gypsy," which is sure to offend someone these days. Along with admonishing customers
to beware of shyster servicemen, there is an example of an orchestrated "sting"
operation whereby a radio set was intentionally "broken" in a certain way with witnesses
as to the fault, and then a couple dozen repair services were called upon to troubleshoot
and fix it, then present a bill for their work. The result is interesting, and even
resulted in one guy being prosecuted. The story reminds me of a similar much-publicized
sting that was done back in the 1990s against car repair services that were creating
leaks in brake lines and then charging customers to fix them...
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 12,000 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.
Aegis Power Systems is a leading supplier
of AC-DC and
DC-DC power supplies for custom and special applications. Aegis has been designing
and building highly reliable custom power supplies since 1995. They offer a complete
line of switch mode power supplies and power converters for a variety of markets
including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft,
EV, telecom, and embedded computing applications. Design and manufacture of custom
power supply solutions to meet each customer's exacting specifications. Please visit
Aegis Power Systems today.
This 1954 issue of Radio-Electronics
magazine reported on the death of electronics communications pioneer
Major Edwin H. Armstrong. Most famously known for his wideband FM (frequency
modulation) scheme, Maj. Armstrong also developed the superheterodyne circuit,
the superregenerative circuit, and was an independent inventor of regeneration.
As with many prodigious, prolific inventors throughout the ages, he spent much time
and fortune battling legal claims against himself and against others. Interestingly,
the news item does not mention that Major Armstrong, who was famous for his daring
antics at the tops of extremely high antennas, died after jumping out of his New
York City apartment window. It was ruled a suicide based on a note he left for his
wife. Also included is a bit about a judge allowing radar data from police as evidence
in a speeding charge, and a statistic showing 47,000 people injured themselves in
the past year during TV antenna installations...
Augustin-Jean Fresnel, the same guy who
developed the "Fresnel zone"
equation for determining the effective RF propagation region between a transmitter
and a receiver, also invented this prismatic lens for concentrating the source of
illumination of a lighthouse in the direction most useful to seafaring vessels (aka
ships and boats). This IEEE Spectrum article entitled "Before Ships Used GPS, There
was the Fresnel Lens" dives into the history of the world-changing device. It
begins: "Ships today use satellite-based radio navigation, GPS, and other tools
to prevent accidents. But back at the beginning of the 19th century, lighthouses
guided ships away from rocky shores using an oil lamp placed between a concave mirror
and a glass lens to produce a beam of light. The mirrors were not very effective,
though, and the lenses were murky. The light was difficult to see from a distance
on a clear night, let alone in heavy fog or a storm..." Here is a nice
video explaining the Fresnel
lens and its nautical import.
Zenith Models 5D011-5D027 schematic and parts list as featured in a 1947 edition
of Radio News magazine. Unlike with most of the Radio Service Data Sheets,
this came from group of three which also included the Bendix Models 636A, C, D and
the Coronet Model C-2, al three of which are tabletop models. As mentioned many
times in the past, I post these online for the benefit of hobbyists looking for
information to assist in repairing or restoring vintage communication equipment...
Planar Monolithic Industries (PMI), a leading
supplier of custom, high-reliability MIC/MMIC components and subsystems for applications
in space, military, communications, commercial and consumer electronics systems
for more than three decades, announces a dba (doing business as) name
change to Quantic PMI. They also have introduced a new 6−Channel Switch
Filter Bank that operates over the frequency range of 55 to 18.5 GHz, with
a typical VSWR of 1.7:1, a maximum switching speed of 200 ns, and a typical
insertion loss of 4.0 dB. Contact PMI today for more information...
electronics-themed comics appeared in a 1952 edition of Radio &
Television News magazine. In the early days of television, it was common in
comedy skits and in cartoons to have someone on a television show interact, to the
viewer's great shock, directly with the viewer or to reach out of the set and do
something, as in the first comic here. The Three Stooges show did that in a couple
shows. One in particular I remember was when they were doing plumbing in a house
and had water coming out of light sockets and telephones. The homeowners were watching
the TV with a film of Niagara Falls when suddenly water came gushing out of the
picture tube (begins at 13:20 in video)...
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
Berkeley Nucleonics Corporation (BNC) is
a leading manufacturer of precision electronic instrumentation for test, measurement,
and nuclear research. Founded in 1963, BNC initially developed custom pulse generators.
We became known for meeting the most stringent requirements for high precision and
stability, and for producing instruments of unsurpassed reliability and performance.
We continue to maintain a leadership position as a developer of custom pulse, signal,
light, and function generators. Our designs incorporate the latest innovations in
software and hardware engineering, surface mount production, and automated testing
Both my father and grandfather were
stamp collectors - philatelists is the technical word - who dabbled in a recreational
way with commemoratives from foreign countries. Nearly all were canceled (used)
stamps that today, as back in their day, have no real value other than to someone
interested in history. Of course none are the rare types. I now possess many of
those stamps in an album that was painstakingly hand-illustrated and assembled to
arrange each stamp according to its country and issue date. At one time I, too,
dabbled in the hobby, having collected many plate blocks and special issue U.S.
stamps in the 1970s and 1980s, along with purchasing a few designs of special purpose
such as those with aerospace and communications themes. Sad to say, most of those
stamps, even those in mint condition, are valued at the denomination printed on
the face - meaning inflation has reduced their worth to even less than when originally
purchased. If indeed "what's past is prologue...