Friday the 3rd
Thursday the 2nd
Wednesday the 1st
Tuesday the 31st
Prior to taking my first chemistry course
while in engineering school, I had experience with using catalysts in compounds
like epoxy adhesives and paints, fiberglass resin, and body putty for fixing cars.
Usually the catalyst part was called a "hardener." It seemed to me the end result
was a solid mass with no apparent separate leftover component. My freshman semester
professor's* claim that, similar to author Swezey's statement, "A catalyst is a
substance which can change the speed of reaction between two or more other substances,
without being permanently changed or used up," was amazing to me. Where did the
catalyst go, then? This "Catalysts
... Secret Agents of Chemistry" article from a 1944 issue of Popular Science
magazine does a nice job of explaining the process, and gives a few examples of
how a catalyst works...
"Expect traffic on the 101 highway in Mountain
View, California, to be even worse in the days or weeks ahead, as motorists slow
down to watch Google co-founder Sergey Brin's 124-meter long airship
Pathfinder 1 launch
into the air for the first time. IEEE Spectrum has learned that LTA Research, the
company that Brin founded in 2015 to develop airships for humanitarian and cargo
transport, received a special airworthiness certificate for the helium-filled airship
in early September. That piece of paper allows the largest aircraft since the ill-fated
Hindenburg to begin flight tests at Moffett Field, a joint civil-military airport
in Silicon Valley, with immediate effect. The certificate permits LTA to fly Pathfinder
1 within the boundaries of Moffett Field and neighboring Palo Alto airport's airspaces,
at a height of up to 460 meters (1500 feet). That will let it venture out over the
south San Francisco Bay, without interfering with planes flying..."
"Modern" is a relative term, and I have
always objected to using it in the title unless a date reference is included. This
article in the March 1935 issue of Radio-Craft magazine is an example.
Some subjects are timeless, like general relativity (pun intended), and are forever
unchanged. In 1935, the Bohr planetary model of the atom was still widely accepted.
Still, the information within is useful for the study of electronics.
Sal ammoniac, mentioned here, is a new term for me; it is a mineral composed
of ammonium chloride. I suppose I should have been familiar with it because of its
use for cleaning soldering iron tips. This compound is another example of how two
otherwise lethal elements can form a molecule that is safe for human consumption,
like sodium chloride (table salt). It is used today in the production of dry cell
batteries, fertilizers, solder flux, fire extinguisher fluid, and even as food flavoring...
Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his October 2023 newsletter that
features his short op-ed entitled "The
Resurgence of the Traveling-Wave Tube." In it, Sam demonstrates an impressive
knowledge of the state of the TWT industry. As is always the case with technology,
the desire for greater functionality, lower cost, higher reliability, and small
size and weight drive the research and development for fulfilling the need. Sometimes
ideas are borne of fantastic fictional accounts of future scenarios, but most often
it is the need to break through the barriers of existing science to achieve a goal.
As the old saying goes, necessity is the mother of invention. Being a frequent surveyor
of tech news sites, I read occasionally of TWT products and research, but I do not
recall seeing where the efficiencies have nearly doubled over previous designs,
so that was a surprise. Incremental advances in TWT research does not receive the
same amount of print space as, say, photovoltaic semiconductors, which produce headlines
whenever scientists manage to squeeze another 0.1% efficiency in the conversion
of sunlight to electricity (in a laboratory environment). Per Sam's piece, the surging
demand for traveling-wave tubes is being driven by the inability of semiconductors
to provide power levels required for unique applications...
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 an
Spurious Product (Mixer) Calculator. 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. Now that a more expandable
basis has been created, I have been adding new calculators on a regular basis...
The
Crosley Roamio 4-A-1 was an automotive radio set that mounted under the cowl
section of the car, with the dial visible below the instrument panel. Thereby, the
lid is easily removable for convenient service. Its schematic, along with a brief
functional description, was published in the June 1935 issue of Radio-Craft
magazine. Although I have not seen it mentioned anywhere, I'm guessing the name
"Roamio" is a play on "Romeo," with the "roam" part alluding to its mobile nature.
A couple photos of the Crosley Roamio were found on the RadioMuseum.org website.
The circuit features a self-rectifying vibrator "B" unit used in the power supply
of this receiver, which generates an alternating current necessary to achieve voltage
step-up transformation. High gain in this receiver has been achieved through the
use of high efficiency R.F. and I.F. coils...
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 (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...
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.
Monday the 30th
Have you ever heard of a "Joy
bomb" in regard to encapsulation of semiconductors in plastic packages? It took
me a moment to figure out what the author was referring to when I read it in this
1967 Radio-Electronics magazine article entitled "Plastic Transistors -
The Future Billions." Joy was (is) a household dishwashing detergent that has been
around since 1949. I still remember the corny "Lemon Joy" commercials from the 1970s
with people being utterly overcome with the joy of seeing their reflections
in the dishes cleaned in Joy... but I digress. Although not explicitly mentioned,
I assume a concentrated liquid soap was used because, as when pouring soap on a
tire when looking for an air leak, a visible bubble will form at the site of the
breach. That was part of the initial investigation into using plastic. We take for
granted cheap plastic packaging, but the transition from bulky, heavy, hollow metal
cans which were vulnerable to vibration, to small. lightweight, fully encapsulated
packages that capture the wirebond connections greatly improved affordability and
reliability...
"In
1964, the office cubicle
was born. For that you can thank Robert Propst, a designer at the Herman Miller
furniture company. Four years earlier, he had proposed a radical alternative to
the office bullpen: the Action Office. He envisioned it as a holistic and integrated
system designed to increase worker efficiency while providing an ergonomic workspace.
Sadly, the Action Office soon devolved into soulless cubicle farms, pilloried in
Dilbert cartoons and despised by office workers everywhere. Chief among the complaints:
noisy coworkers and a lack of privacy. To address both issues, Propst and Jack Kelley
created the Acoustic Area Conditioner in 1975. The AAC was a noise-canceling device
designed to hush unwanted background chatter. The globe became known around the
company as the maskitball..."
In Part 4 of his "(Re)Discovering
the Lost Science of Near-Field Measurements" series, Ken Javor asserts: "Understanding
Radiated Emissions Measurements Made at One-Meter Separation: It's Not What You've
Been Led to Believe This is the final installment of this serialized article. The
first installment explained what near and far field measurements entail, and that
one-meter measurements are very much near field. The second installment explained
the evolution of the earlier 12" and present-day one-meter separation measurements,
considerations in antenna selection, the difference between antenna-induced and
field strength limits, and the evolution from one to the other. The third installment
investigated practical problems arising from the misapplication of field intensity
and far-field concepts to near-field phenomena. This fourth and final installment
lists theoretical misunderstandings arising from the erroneous substitution of field
intensity for antenna-induced concepts and shows the serious practical outcomes
that result from these theoretical mistakes. Theoretical Problems Resulting from
Using Field Intensity Limits Where Antenna-Induced Is More Appropriate Ignorance
of the fundamentals of extreme near field measurements and of gain derating and
the nature of the Fresnel zone has pronounced and dangerous impacts on both EMI
and EMC requirements and verification. The following sections provide some relevant
case histories..."
The following announcement was posted in
the September 1930 edition of Radio-Craft magazine regarding Radio Data
Service Sheets. Oddly, I don't recall knowing that the "Radio Service" part of Radio
Service Data Sheet referred to the name of a company/publisher. They must have been
like an early version of Sam's Photofact subscription plan. Radio-Craft
continues to produce the Data sheets for many years. "We are pleased to announce
that RADIO-CRAFT has taken over the subscription list of 'RADIO SERVICE,' formerly
published in Dallas, Texas. All subscribers of record to RADIO SERVICE will receive
RADIO-CRAFT until the expiration of their subscriptions." I could not locate a photo
of the
Colonial Model 31 / 32 "DC" radio, but did find a model 31 AC. The DC and AC
models likely used the same chassis, with the only difference being the AC operated
off line current and DC used a battery. Up until the Tennessee Valley Authority
(TVA) was established later in the 1930s, most rural areas did not have AC electric
service and relied on banks of storage batteries...
Banner Ads are rotated in all locations
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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...
Werbel Microwave is a manufacturer of RF
directional and bidirectional couplers (6 dB to 30 dB) and RF power dividers
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designed and manufactured in our Whippany, NJ, location. Custom products and private
label service available. Please take a couple minutes to visit their website and
see how Werbel Microwave can help you today.
Sunday the 29th
As with my hundreds of previous engineering
and science-themed crossword puzzles, this one for October 29th uses only clues
and terms associated with engineering, science, physical, astronomy, mathematics,
chemistry, etc., which I have built up over more than two decades. Many new words
and company names have been added that had not even been added to the world's technical
lexicon when I started in the year 2002. 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. You might,
however, encounter the name of a movie star like Hedy Lamarr or a geographical location
like Tunguska, Russia, for reasons which, if you don't already know, might surprise
you. The technically inclined cruciverbalists amongst us will appreciate the
effort. A full list of all RF Cafe crosswords is at the page bottom. Enjoy!
One aspect of advertising on the RF Cafe
website I have not covered is using
Google AdSense.
The reason is that I never took the time to explore how - or even whether it is
possible - to target a specific website for displaying your banner ads. A couple
display opportunities have always been provided for Google Ads to display, but the
vast majority of advertising on RF Cafe is done via private advertisers. That is,
companies deal with me directly and I handle inserting their banner ads into the
html page code that randomly selects and displays them. My advertising scheme is
what the industry refers to as a "Tenancy Campaign," whereby a flat price per month
is paid regardless of number of impressions or clicks. It is the simplest format
and has seemed to work well for many companies. With nearly 4 million pageviews
per year for RFCafe.com, the average impression rate per banner ad is about 220,000
per year (in six locations on each page, with >17,000 pages). That's pretty good
exposure for $300 per month. Some companies have expressed an interest in being
able to manage their advertising accounts themselves a la the Google AdSense program...
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. Manufactured in the USA.
Friday the 27th
As one who made
in-home service calls for a few years as an electrician, I can attest to the
sometimes strange scenarios which can be experienced. Most of the time the customers
were sane and cordial, but every once in a while a lunatic answered the door. I
always went out of my way to be accommodating and polite. One of the strangest places
was a very expensive home that had essentially been outfitted as an aviary for various
breeds of parrots. The owner insisted I never open a door or window without her
being present. Bird poop was all over everything - furniture, curtains, kitchen
stove and sink. Yuk. I got out of there as quickly as possible. Being in Annapolis,
MD, near water (Chesapeake Bay and tributaries), lots of creepy-crawlies were everywhere,
especially under houses. I can't count the number of times I met with nasty spiders,
bees and wasps, multi-legged whatevers, and snakes whilst working deep inside crawl
spaces and attics - with no expedient means of egress. In the 1970s there were no
high power LED flashlights (or cellphones with a "flashlight" app) that lasted for
hours, just D-cell flashlights with a PR-2 incandescent bulb that varied in brightness
from moment to moment. Panic ensued when all of a sudden the light failed and there
was no perceptible light marking a safe exit path. One old guy was a retired physics
instructor at the U.S. Naval Academy, and he lectured me severely for daring to
drill a couple holes...
"The World Above 50 MHz" is admittedly not
a QST magazine column I usually read through each month, but the "August
2023 Heat Wave Tropospheric Opening" headline caught my attention. DXing (long
distance communications) is a passion for many amateur radio operators, and much
effort goes into making worldwide contacts, particularly by using as little transmitter
power as possible (just about anyone with a maximum PEP power amplifier, expensive
low-loss transmission line, a monster antenna, and a state-of-the-art transceiver
can be successful). When an "opening" occurs due to ionospheric charging of atmospheric
layers, it usually lasts for a relatively short time - from minutes to hours or
maybe a couple days. According to K1HTV, "In my 65+ years of VHF DXing, this is
the longest continuous tropospheric opening I have ever seen." VHF operators were
"astonished" by a heat wave tropospheric opening, which don't usually occur at temperatures
greater than 100°F, but this one lasted August 19-24 with temps in the 100°F realm.
The included map shows contact locations
and durations. Unfortunately, the article is only available to ARRL members.
Having been out of the RF system design
realm for a few years, I do not have much cause to think about mixer spurious products
anymore. This "Linear
Scales Show Mixer Harmonics" article from a 1964 issue of Electronics
magazine got me thinking about it. I wonder these days how many designers even do
much in the way of frequency planning in conversion systems? Are the RF, IF, and
baseband frequencies so well defined for most of what is done in the wireless world
that all the spurious product issues have been solved and there are few people who
need to calculate mixer spurious product frequencies and powers? If there is a need,
what methods are currently being used? Do you still cobble together spreadsheets
and/or MATLAB worksheets using equations like those presented here, do you have
a favorite smartphone app, a compact program on your computer, or are you using
one of the two or three uber-sophisticated and super expensive design engineering
programs...
"It's
the season for space-based cellular service, courtesy of a recent string of announcements
from companies around the world. Huawei upgraded its China-only satellite service
from messaging to video calling this summer using its latest handset, the Mate 60
Pro, while AST SpaceMobile
made its first 5G voice and data call using its prototype BlueWalker 3 satellite
and a standard Samsung Galaxy S22. Apple's September announcement of its latest
mobile telephone mentioned the subtle expansion of its emergency satellite messaging
service to include roadside assistance. The flurry of activity adds up to a sign
that companies are making progress on providing cellular service via satellite.
'I would say that most of the initiatives have moved from establishment phase to
consolidation phase,' says Derek Long, the head of telecommunications at Cambridge
Consultants. Yet consolidation does not necessarily mean the companies are meeting
the goals they set last year. At the start of 2023, I reported on predictions from
these companies..."
The
Brunswick Model 31 Combination Radio Panatrope was billed as the world's first
all-electric phonograph (as opposed to the mechanical crank-up models), combined
with an AM radio. It was designed with the assistance of RCA, many of whose components
were integrated into the unit. A video of a restored Panatrope is embedded on the
page below the data sheet. I couldn't find an official etymology for "panatrope,"
but the prefix "pan" means "all-inclusive," and "trope" means "turning," like the
turning of a phrase. However, given that the Panatrope is a "turn"table, perhaps
that was an intentional distortion of the meaning to fit the device which it named,
ergo, a record player that had all available functions. That's my best shot at it.
This Radio Service Data Sheet for the Brunswick Model 31 Combination Radio and Panatrope
appeared in the February 1930 issue of Radio-Craft magazine. It includes schematics
and very detailed alignment instructions. A video of one in operation is embedded
below.
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...
Exodus Advanced Communications is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Power amplifiers ranging
from 10 kHz to 51 GHz with various output power levels and noise figure
ranges, we fully support custom designs and manufacturing requirements for both
small and large volume levels. decades of combined experience in the RF field for
numerous applications including military jamming, communications, radar, EMI/EMC
and various commercial projects with all designing and manufacturing of our HPA,
MPA, and LNA products in-house.
Thursday the 26th
You have likely heard of the International
Geophysical Year (year and a half, actually), which was timed to coincide with maximum
solar activity beginning in June 30, 1957, but have you heard of the Second Polar
Year, a 13-month period that began in August 1932? It was conducted at a time when
long range radio communications was becoming a major geopolitical necessity and
scientists needed to better understand the phenomena of ionization in the Earth's
upper atmosphere (named as a result - you guessed it - the ionosphere). Critical
World War II radio communications were hampered by atmospheric electrical disturbances;
likewise during the Korean War. When the Space Age was in its early years, learning
about how radiation in all forms affect both electrical and biological (i.e., human)
entities was essential in order to mitigate harmful effects and assure their safety.
This "Superstorms
That Rage in Silence" article in a 1968 issue of Popular Mechanics magazine
discusses the consequences of solar activity on Earth-based systems - particularly
the power distribution grid...
"The strange quantum phenomenon known as
entanglement
can link atoms and other particles together so that they can influence one another
instantaneously, regardless of distance. New research suggests it's possible to
take advantage of entanglement for significantly more accurate and faster quantum
sensors that could support satellite navigation technologies like GPS. Quantum sensors
rely on the effects that can emerge, because the universe becomes a fuzzy place
at the smallest perspectives. These quantum effects are notoriously fragile to outside
interference. However, quantum sensors capitalize on this vulnerability in order
to respond to the slightest disturbances in the environment. Increasingly, quantum
sensors are reaching unprecedented levels..."
This is the
electronics market prediction for Italy, circa 1966. It was part of a comprehensive
assessment by the editors of Electronics magazine of the state of commercial,
military, and consumer electronics at the end of 1965. Computers, military communications,
numerically controlled factory automation, and consumer electronics drove the Italian
markets, as was the case for every first-world nation. A bigger concentration on
exports was becoming an important part of the equation. Unless you can find a news
story on the state of the industry, detailed reports must be purchased from research
companies like Statista. Their website has a lot of charts on Italy's current electronics
market showing revenue in the consumer electronics segment amounts of US$2,948M
in 2020...
In 1938, the designers at Sears, Roebuck &
Company's, Silvertone radio division were truly thinking "outside the box" when
they came up with this
"Rocket" model 6110. It is an ultra compact tabletop design with a unique rounded
top and a huge tuning dial that comprised one entire end of the Bakelite cabinet,
along with a set of six pushbuttons for station recall. There were only four vacuum
tubes in the signal path so it was probably not the the highest quality sound or
tuning selectivity. The "Rocket" nomenclature certainly fit its futuristic looks.
The Tube Radio Land website has a good description of the radio. The world was fascinated
with rockets at the time, being just a decade since Robert Goddard conducted his
first liquid fueled rocket launch in 1926. There are still many people who restore
and service these vintage radios, and often it can be difficult or impossible to
find schematics and/or tuning information...
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We Are
the World's Matchmakers" Smith chart design. These would make excellent gifts
for husbands, wives, kids, significant others, and for handing out at company events
or as rewards for excellent service. My graphic has been ripped off by other people
and used on their products, so please be sure to purchase only official RF Cafe
gear. I only make a couple bucks on each sale - the rest goes to Cafe Press. It's
a great way to help support RF Cafe. Thanks...
Withwave manufactures an extensive line
of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
fully automated
4-port vector network analyzer (VNA) calibrator, between- and in-series connector
adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes &
probe positioner. Special test fixtures for calibration and multicoax cable assemblies.
Frequency ranges from DC through 110 GHz. Please contact Withwave today to
see how they can help your project succeed.
Wednesday the 25th
Abbreviations, acronyms, and initialisms
abound in all technical fields, and electronics is no exception. Generally, the
coined names are based on the (usually) first letters of words comprising the entity
(e.g., metal oxide semiconductor field effect transistor - MOSFET) when the originators
are affiliated with private and academic organizations. Government and military
groups are famous for twisting and distorting entity names to create descriptive
acronyms, like Nanoscale Architectures for Coherent Hyper-Optic Sources (NACHOS),
NASA's Space Communications and Navigation (SCaN), and Counter-electronics High-powered
Microwave Advanced Missile Project (CHAMP). I just checked in with Wikipedia and
found a list of a couple dozen of transistor-related acronyms, which includes MOSFET,
DGMOSFET, DGMOS, BJT, SCR, IGBT, JLNT, MNOS, ISFET, BioFET, EnFET, GenFET, DNAFET,
CPFET, BeetleFET, DNAFET, finFET, GAAFET, JFET, DEPFET, FREDFET, HIGFET, MODFET,
TFET, TQFET, HEMT, HFET, MESFET, NOMFET, GNRFET, VeSFET, CNTFET, OFET, QFET, GFET,
VTFET, and others. Determining the meaning and properties of each type is left as
an exercise for the reader ;-)
"Researchers from MIT and the Institute
of Science and Technology Austria have created a technique to include many different
building blocks of cellular
metamaterials into one, unified graph-based representation. They used this representation
to create a user-friendly interface that an engineer can utilize to quickly and
easily model metamaterials, edit the structures, and simulate their properties.
With a new, user-friendly interface, researchers can quickly design many cellular
metamaterial structures that have unique mechanical properties. Engineers are constantly
searching for materials with novel, desirable property combinations. For example,
an ultra-strong, lightweight material could be used to make airplanes and cars more
fuel-efficient, or a material that is porous..."
Here is a good, brief introduction to
harmonic and intermodulation distortion measurement methods that were commonly
used in the 1960s. Total harmonic distortion (THD) was used often, especially for
audio equipment, which of course most frequency conversion circuits ultimately were
in the era since digital data transmission over the air was not too common. Author
Charles Moore worked for Hewlett-Packard (HP) and references HP Application Note 15,
"Distortion and Intermodulation" which, thankfully, is made available by The HP
Memory Project website. In fact, a complete list of all the vintage app notes are
available on this page by downloading the PDF files. I highly recommend that you
download and save all you think you might ever want because as with most things
on the Web, they could disappear at any time. Some have been captured on the Archive.org
website (I just now had it save AN-15 for time immemorial)...
This Radio Service Data Sheet for the
American
Bosch Models 60 and 61 was published in the August 1931 issue of Radio-Craft
magazine. I searched high and low on the Internet for a photo of an actual radio.
Models 5, 28, 30, 48, and 200 are aplenty, but alas, no 60 or 61. Features like
automatic volume control (AVC) were considered deluxe niceties available to the
consumer willing to pay extra for it. There are five vacuum tubes in the signal
path, not including a separate tube for the AVC circuit. Two rectifier tubes are
in the power supply, and a neon bulb is used as a power on indicator. With this
number of tubes, it could be either a high-end tabletop job or a console type floor
model. Bosch was first a German electronics company before expanding to America...
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!
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prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.
Tuesday the 24th
Popular Electronics magazine's quizmeister
Robert P. Balin created this "Voltage
Quiz" for the December 1961 issue. Fortunately, only fixed resistors (6 Ω
each) and battery voltage source(s) are involved. The goal is to calculate the voltage
at point "A" with respect to ground. Analyzing some of the circuits is made easier
by rearranging the layout to remove wiring overlaps. Circuit 5 might be the
simplest of all, and can be done fairly easily in your head. Others, like circuit 1,
are best approached by writing two mesh equations per Kirchhoff's voltage law (the
sum of all voltages in a closed circuit equals zero) and solving the resulting two
equations in two unknowns (basic algebra). Spoiler: Upon redrawing a couple circuits
you might discover an identical instance of a previous one, making the solution
the same as well...
"The 69th Annual IEEE International Electron
Device Meeting is set to start on 9 December, and the conference teaser shows that
researchers have been extending the roadmap for a number of technologies, notably
those used to make CPUs and GPUs. Because chip companies can't keep on increasing
transistor density by scaling down chip features in two dimensions, they have moved
into the third dimension by stacking chips on top of each other. Now they're working
to build transistors on top of each other within those chips. Next, it appears likely,
they will squeeze still more into the third dimension by designing
3D circuits with 2D semiconductors,
such as molybdenum disulfide. All of these technologies will likely serve machine
learning, an application with an ever-growing appetite for processing power. But
other research to be presented at IEDM shows that 3D silicon and 2D semiconductors..."
Meteor scatter (aka meteor burst)
communications is today largely the domain of amateur radio operators in their
ongoing attempts to set records for making long distance (DX) contacts with a minimum
amount of transmit power. When this article was written by U. California's Victor
Latorre, transcontinental fiber optic cables did not interconnect the world with
high speed, phase stable media that meets the exacting needs of precise time synchronization.
Radio astronomy, quantum physics experiments, and even stock market trading (see
Arbitrage via Microwaves) depends on microsecond or finer timing. Mr. Latorre
explains in this 1965 issue of Electronics magazine how meteor scatter
communications' unique phase-stable characteristic is used to send synchronization
signals between scientific and navigation facilities. Of course meteor scatter has
the severe disadvantages of being unpredictable in time and place, short-lived,
and varying in levels of ionization of the upper atmosphere with attendant frequency
and bandwidth accommodation. That very unpredictablity...
Evidently
the ARRL's QST magazine editor(s) believe registering with the FCC's new
COmmission REgistration System (CORES)
is essential, because full-page articles appeared in both the October and November
issues. Say the authors, "Before you renew your license, you will need to create
a new FCC CORES username account, and then link your FCC Registration Number (FRN)
to your new account. As of April 2022, the FCC charges a $35 fee to renew amateur
radio licenses. You must create the new account to pay the fee." I did mine back
when CORES was first established and had no problems. However, when I just now tried
to log in to review my information, the password didn't work and I needed to reset
and create a new one. Evidently the FCC has changed its password character content
requirements since then. My Amateur Extra license expires in 2030, so it'll be a
while before needing to update. I wonder if my password will work in 2030?
Here is the
Delco 32-Volt Radio Receiver Chassis schematic and parts list as featured in
a 1933 edition of Radio-Craft magazine. The only example I could find is
the one shown to the left, on the PhilcoRadio.com website. The schematic shows six
vacuum tubes, and there appears to be six in the photo. Battery-powered radios were
common in the era before AC electric service was available in rural locations, and
a lot of homes even in the cities did not have service either. A look through a
Sears, Roebuck & Co. catalog in the early part of the last century showed many
electricity generator systems for use on farms, including windmills and water-powered
generators for placing in streams and rivers. Life was tough...
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...
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.
Monday the 23rd
In July 1966, Popular Electronics
magazine invited its readers to submit examples of ridiculous statements made by
people supposedly "in-the-know" about electronics and/or technical subjects. Space
was allotted to it in four later issues as well, all of which I have now posted
with Sequel 4 of "Just
When I Forgot My (Soldering) Gun!" finishing it out. Stories of customer remarks
are always good for a laugh, like the housewife (remember those?) of an engineer
who, upon having a repairman tell her the TV had a problem with an intermittent
tube, called her husband and told him to pick up a new intermittent tube. Then there
are the puns, like Mad Magazine's Alfred E. Neumann exclaimed on seeing his new
ham ticket, "What me W0RRY?," and that connecting together all the batteries on
earth end-to-end you would have a world series. What about having your color TV
picture tube "deloused?" Enjoy...
"BT today announces the launch of the UK's
first
Drone SIM to unlock the true potential of beyond visual line of sight (BVLOs)
drone operation across the UK. Designed to function at altitude using the EE network,
Drone SIM offers unlimited data plans and continuous connectivity in the sky. Drone
SIM is built to endure vibration, temperature and humidity extremes, supporting
all-season drone use. BT business customers will be the first to benefit from the
Drone SIM which has the potential to transform industries, from urgent delivery
of medical supplies to infrastructure monitoring and transportation of goods. Using
BT Group's EE network, Drone SIM benefits from high priority and ultra responsive
connectivity, enabling safety, control, telemetry and realising ultra-high definition
(UHD) video streaming at altitude. This enables drone users to capture detailed,
survey quality imagery and video for a wide range of purposes, from search and rescue
to infrastructure inspection. Drone SIM is pushing the limits of drone flight..."
Often times, a recent convert, adopter,
proselyte, or whatever name you give to a newly energized person who has a new activity
or lifestyle, is among the most ardent of disciples for that realm. That goes for
religions, weight loss and smoking cessation programs, social and political movements,
and even hobbies. Recipients of that person's enthusiastic dogma view such evangelism
as anything from welcome news worthy of adoption to merely annoying to downright
offensive and unbearable. Since receiving my first
Amateur Radio operator's license in 2010, long-time visitors of RF Cafe have
probably noticed an increase in the number of Ham-related news stories and magazine
articles on the subject. Hopefully, my interspersing them with more career-centric
engineering and technical content is not regarded as superfluous to non-Hams. The
fact is that even if you have no interest in becoming an Amateur Radio operator,
the incredible amount of information generated by the Ham community - which consists
in a large part of electronics engineers and technicians - is beneficial to the
majority of people in the professional field. So, if you think I have gone overboard...
The December 1965 issue of Electronics
magazine reported in multiple articles on the state of
Japan's electronics industry (see the table of contents for other stories).
Japan's indisputable lead today in many realms of semiconductor, commercial, and
consumer products proves successful implementation of the strategy described in
these articles. Per this piece's NTT employee authors, "In one decade, Japan's semiconductor
industry has become the world's second largest. Pioneering engineers, a variety
of unusual devices, and breakthroughs in miniaturization techniques account for
phenomenal growth." A notable claim is taking credit for inventing the ceramic "pill"
packaging format for high frequency transistors...
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With more than 17,000 pages in the Google search index, RF Cafe returns in
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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...
TotalTemp Technologies has more than 40
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how they can help your project.
Sunday the 22nd
As with my hundreds of previous
engineering and science-themed crossword puzzles, this one for October 22nd
uses only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc., which I have built up over more than two decades.
Many new words and company names have been added that had not even been added to
the world's technical lexicon when I started in the year 2002. 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. You might, however, encounter the name of a movie star like Hedy Lamarr or
a geographical location like Tunguska, Russia, for reasons which, if you don't already
know, might surprise you. The technically inclined cruciverbalists amongst us will
appreciate the effort. A full list of all RF Cafe crosswords is at the page bottom.
Enjoy!
Anatech Electronics (AEI) manufactures and
supplies RF and microwave filters for military and commercial communication
systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters,
and RF products. Standard RF filter and cable assembly products are published in
our website database for ease of procurement. Custom RF filters designs are used
when a standard cannot be found, or the requirements dictate a custom approach for
your military and commercial communications needs. Sam Benzacar's monthly newsletters
address contemporary wireless subjects. Please visit Anatech today to see how they
can help your project succeed.
