See Page 1 |
2 |
3 |
4 | of the December 2023 homepage archives.
Final Electronics-Theme Crossword for 2023!
This is the
RF Cafe electronics theme crossword puzzle is for December 31st. Hard to
believe it is the final crossword for 2023! This being the 31st day of the month,
many of the words begin and/or end with the letter "E." Since there are only 26
letters in the alphabet, I use the modulo function to derive the letter to use;
i.e., 31 mod 26 = 5. Clues for words containing "E" are marked with an asterisk
(*). Related clues are marked with an asterisk (*). 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, Hedy
Lamarr, or the Tunguska event in Siberia). The technically inclined cruciverbalists
amongst us will appreciate the effort. Enjoy!
Get Your Custom-Designed RF Cafe
Gear!
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...
Friday the 29th
War Advertising Council
I'm probably one of the few people remaining
who fairly regularly recite the World War II (WWII) era slogan of "Use
it up. Wear it out. Make it do, or Do without." One of the primary killers of
economies has been inflation, whatever the cause - usually deficit spending by government
and/or printing of fiat money. Wartime typically produces high inflation levels
due to the need to produce the equipment necessary to wage a battle. Supply and
demand are another cause of inflation. If the demand is greater than the supply,
prices go up because owners want to maximize profits. If the need for skilled labor
is greater than what is available, workers demand higher pay, and the price goes
up. During WWII, as the chart to the upper left shows, inflation rates were sky
high, and the government propagandists called on the citizens to "do their part"
to keep prices under control by not creating a higher demand then the supply chain
could accommodate...
Radio Dumping
"The situation is one that is difficult,
if not wholly impossible to eradicate, because of all modern, 20th Century machine
age products, the radio receiver of today undergoes more violent and more radical
changes than almost any other single item we can think of." That was the lament
of electronics inventor, publisher, and industry visionary Hugo Gernsback in 1939!
He wrote in the February issue of Radio-Craft magazine of the practice
of
electronics component manufacturers vastly overproducing products and then,
when they are quickly obsoleted due to newer better ones entering the market space,
selling at below cost in hopes of recovering at least some of their investment.
For a man who otherwise encouraged, welcomed, and participated in the pushing forward
of technological frontiers, the attitude seem strangely at odds with his raison
d'être. "This 'dog eat dog' process has gone on ever since and will probably go
on for a long time to come." He had no idea ... or maybe he did...
Superatomic Semiconductor Sets Speed Record
"Semiconductors, particularly silicon, are
fundamental to the operation of various electronic devices such as computers, cellphones,
and the device you're currently using. Despite their widespread use, semiconductors
have inherent constraints. The atomic structure of these materials is subject to
vibrations, resulting in the generation of quantum particles known as phonons. These
phonons lead to scattering of the particles - either electrons or electron-hole
pairs termed excitons - responsible for transporting energy and information in electronic
devices. The scattering occurs over extremely small distances (nanometers) and brief
time spans (femtoseconds), causing energy dissipation as heat and imposing a limit
on the speed of information transfer. The search is on for better options. Writing
in Science, a team of chemists at Columbia University led by Jack Tulyag, a PhD
student working with chemistry professor Milan Delor, describes the fastest and
most efficient semiconductor yet: a
superatomic material called Re6Se8Cl2..."
The Radio Month in Review
Did you know that some radio service equipment
can be financed by the Federal Housing Administration (FHA)? That's right, if your
business needs a new tube tester or maybe an oscilloscope, Uncle Sam is there to
help. That was in 1936, anyway, per this Radio-Craft magazine news blurb.
Today, of course, the FHA no longer makes loans for business equipment - the Small
Business Administration (SBA) takes care of that. Nowadays the FHA restricts itself
to home loans - including to illegal residents, those with no money for a down payment,
and otherwise traditionally unqualified. Also reported, among lots of other interesting
stuff, is some early instances of RFI (radio frequency interference) emanating from
hospital equipment. Oh, and an anecdote regarding a Babe Ruth run-in with the coppers.
Note the
Thompson submachine gun (aka Tommy gun) pointed at him in the drawing.
RF & Electronics Symbols
for Office™
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!
Thursday the 28th
Forecaster Dials Weather from Known Conditions
"Home
Forecaster Dials Weather from Known Conditions" is the title of this news blurb
from a 1943 issue of Popular Mechanics magazine. Back when I was a kid
in the 1960s and 1970s, dialing the weather meant inserting my index finger into
the holes on the rotary phone and dialing WE6-1212 (the time was gotten by dialing
TI6-1212), and then listening to the recorded current conditions and forecast for
the next 24 hours. I called often (my father referred to the recording lady as my
girlfriend) due to both a keen interest in weather phenomena and wanting to know
whether the conditions would be good for flying a model airplane or launching a
model rocket. This cardboard dial calculator required the user to input current
observed conditions for wind direction, barometric pressure and whether it was rising
or falling, and your opinion on whether the weather (see what I did there?) was
"fair," "overcast" or "raining." I assume "snow" could be substituted for "rain"
if appropriate. The device would then provide a forecast for the next 12-24 hours,
within a radius of about 30-50 miles. When taking private pilot lessons in the late
1970s, I was taught to estimate conditions in somewhat the same manner, except cloud
type is a good visual indicator of things to come. Winds aloft, distant high and
low pressure systems...
Eliminating Rare Earth Metals in EVs
Electronic Design magazine has
been running a series of articles highlighting new motor technology that eliminates
the need for rare earth element permanent magnets, thus removing China and other
hostile nations from the supply chain. Known as
wound-rotor synchronous motors (WRSM), they replace the now-standard permanent-magnet
synchronous motors (PMSM) by substituting permanent magnets with electromagnets.
Doing so requires a battery to generate the magnetic field to get the motor started
and to sustain operation, thus reducing its overall efficiency, but not by so much
as to make it undesirable. Some versions of the WRSM use slip rings for conducting
current to the field windings, but designs are appearing which use induction to
eliminate physical (and thus wearing) contact. I personally hope this technology
mature quickly. More essential, though, is to find a replacement for
lithium battery cells that does not require such massive mining operations that
destroy the environment around them and harbor unsafe working conditions that would
not be tolerated by OSHA in this country. Here are
Part 1,
Part 2, and
Part 3.
The Radio Manufacturer Has His Say
Unlike the last two decades where people
like me have been making it available, procuring
service information on commercial products could be very time consuming, and
often resulted in not even obtaining what was needed. Thanks to the Internet now
being populated with schematics and mechanical drawings for seemingly everything
ever made, we no longer need to call or mail order for information needed to repair
your radio, television, cellphone, lawn mower, toaster, or anything else. Granted,
most people these days toss out broken items and just buy new ones. Before the advent
of companies like Sam's Technical Publishing information packets, it was often impossible
to obtain schematics and service information from manufacturers unless you were
a certified service shop and/or dealership. In response to many inquiries from
Radio-Craft magazine's readers, publisher Hugo Gernsback queried the top
manufacturers of the day to determine their policies for distributing such data...
Metasurface Antenna for High-Security 6G
"A research team led by Professor Chan Chi-hou,
Chair Professor of Electronic Engineering at City University of Hong Kong, achieved
an unprecedented advance in antenna technology by making possible the manipulation
of all five fundamental properties of electromagnetic waves through software control.
In a world first, the team developed a universal
metasurface antenna that allows the independent and simultaneous manipulation
of amplitude, phase, frequency, polarization and direction of electromagnetic radiation.
'A universal component capable of manipulating all the fundamental wave properties
is the Holy Grail for physicists and engineers,' said Professor Chan, who is also
Director of the State Key Laboratory of Terahertz and Millimeter Waves (SKLTMW).
As research on 6G wireless communication systems progresses worldwide, the universal
metasurface antenna holds immense potential for various applications in 6G systems.
Its advanced waveform manipulation capabilities and enhanced security features are
crucial for integrating sensing..."
Cartoon Advertising for Radio Service Men
The Star Radio Company, in Washington, D.C.,
was lauded in its day for pioneering the use of
humor in its print advertising. This 1933 issue of Radio-Craft magazine presents
a few examples of their handiwork - some of which would probably never be approved
for publication in today's hypersensitive environment. I searched for more info
on the company, but all I could find was a Library of Congress photo of a display
of automatic washers and ironers - considered as high tech in the day as any vacuum
tube radio. My grandmother had one of those wringer washing machines back in the
1960s. The wringer mechanisms were real safety hazards, hence the old quip about
there not having been so much excitement around the house since granny got her <3-letter
word> caught in the wringer. Anyway, enjoy the cartoon ads as you're waiting
for the first weekend in spring...
RF & Electronics
Stencils for Visio
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...
Wednesday the 27th
1958 Old Farmer's Almanac Puzzles
If you like
solving puzzles, maybe you'll want to give these from the 1958 issue of The
Old Farmer's Almanac (OFA) a try. I through V are pretty straightforward,
but VI and VII are a tad strange. Don't overthink VI and VII because they're not
brainiac material. I plugged part of the solution into Google and could not find
anything that indicates they descend from some great works or prose. I worked them
out to demonstrate what I mean. Puzzles I through V do not contain any tricks, just
solve them as presented and you'll have no problem. Thought processes were different
back in the day, as is evidenced by looking at some of the other OFA puzzles
in the list...
Attracting Customers Who Want to
Thermal Testing
Meeting the required
thermal testing requirements and performing it in less time is what TotalTemp
Technologies offers. When a device is suited to testing on a thermal platform, that
will always be our first recommendation. That is to say, the device has a fairly
low profile and a flat thermally conductive surface. Fortunately, many electronic
modules such as microwave modules and power amplifiers are already optimized for
this configuration of test. Applying some thought to the process can make it more
efficient. If a little bit of fixturing helps the device have a good thermally conductive
surface, that will go a long way to facilitate faster testing. A secondary sensor
on the device, especially if it is tall, can tell you when the point you actually
care about has reached the required temperature. The optional Synergy Nano advanced
temperature control algorithm can assure the fastest ramp to temperature and avoid
excessive overshoot, which could damage parts. Keeping in mind how much more effective
conductive heat transfer is, sometimes it just doesn't work for the device to be
tested. In that case, a temperature chamber remains the best choice, TotalTemp is
here to offer temperature chambers with fast, programmable transition rates and
sufficient airflow to ensure good heat transfers to and from the device...
Decoding the Invention of the Radio
Here
is an interesting discussion on the TruthOrFiction.com website entitled "Decoding
the Invention of the Radio: A Scientific Retrospection." Attempting to discredit
and/or defame historical figures for their accomplishments is a form of sport these
days. Tearing down monuments, renaming institutions, banning publications, and demanding
that people accept and even rejoice in those practices has reached pandemic proportions.
I have nothing against legitimate research showing that past assumptions were in
error. Some keep trying to show Einstein's theory of general relativity is
wrong, or that
Whitehead
flew a powered airplane before the Wrights, or that
Gray had a working telephone prior to Bell. This article does not attempt to
fully discredit Maxwell as the inventor of radio, but points out that many others,
including Tesla, Hertz, Popov, and Lodge contributed greatly to the knowledge that
facilitated Marconi's success. While a useful story, my guess is that it is "preaching
to the choir" instance since most people capable of answering the question of "Who
invented the radio," with a reply of James Clerk Maxwell also know of the other
men's work. That is probably not as true for the invention of the aeroplane or the
telephone...
Short-Cuts in Radio
First prize in this circa 1936 reader-submitted
design ideas went to William G. Scott for his
wind-powered battery recharger. It was a rather elaborate contraption made of
surplus lawn mower and automobile (Ford Model T, no less) generators. There are
two very good reasons why someone would find the need to build his own battery charger
in the era. First, good luck finding a commercial product to do the job, and if
you could, the cost would be prohibitive for most radio enthusiasts. Second, prior
to the Rural Electrification Act of 1936 (which took many years to fully implement),
most households not in or near cities and towns had no commercial electric service.
Electricity, if any, was supplied by deep cycle storage batteries for powering radios,
electric lights (as opposed to kerosene or gas lights), kitchen appliances, etc.
Many farms had windmills that did double duty of pumping ground water and driving
a generator. BTW, a $10 prize in 1936 is, according to the BLS' Inflation Calculator,
the equivalent of $219 in 2023 money...
How to Target RFCafe.com for Your Google Ads
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 280,000
per year (in eight 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...
Thanks to Copper Mountain Technologies
for Continued Support
Copper Mountain Technologies develops innovative
and robust RF test and measurement solutions for engineers all over the world. Copper
Mountain's extensive line of unique form factor
Vector Network Analyzers
include an RF measurement module and a software application which runs on any Windows
PC, laptop or tablet, connecting to the measurement hardware via USB interface.
The result is a lower cost, faster, more effective test process that fits into the
modern workspace in lab, production, field and secure testing environments. 50 Ω
and 75 Ω models are available, along with a full line of precision calibration
and connector adaptors.
Tuesday the 26th
Radio Corporation of America
The
Radio Corporation of America, more widely known as RCA, contributed as mightily
to the science of wired and wireless communications as International Business Machines
(IBM) did to analog and digital computing. Inventions created by RCA for specific
applications were often repurposed (a word not even in existence - or at least common
parlance - in 1953 when this appeared in Popular Mechanics magazine) for
other uses. Such was the case for the
multiplier phototube - which is nowadays referred to as a photomultiplier tube
(PMT). RCA engineers used a PMT designed to be sensitive enough to detect starlight
through a telescope, in a circuit that detects the headlights of oncoming cars and
switches the host car's headlights off of high beam (if that's where they were set).
Many - maybe most - of the Popular Electronics, Mechanix Illustrated,
and Popular Science magazines I have from that era feature similar full-page
ads by RCA and Bell Telephone Laboratories. They also showed up in magazines like
The Saturday Evening Post, Time, and many women's magazines. Reminding
the public of the services provided engendered...
Radio Training Association of America
Imagine having a serviceman of any sort
arrive at your house, fix your problem, and present you with a bill of $6 - parts
included. He would walk away satisfied that he had done a good job and was well
compensated for the work considering the effort invested in training and qualification.
$6 in 1932 when this
Radio Training Association of America ad appeared in Radio-Craft magazine,
per the Bureau of Labor Statistics' Inflation Calculator is worth $135 in 2023 money
- that's a cheap service call even in today's economy. Further, the $14 stated as
a day's earnings is $316 in 2023, which equates to 50 work weeks/year x 5 days/week
x $316/day = $79,000/year - not too shabby. Just between you and me, that's more
than I'm currently making per year...
Flow Batteries Replace Lithium
A new paradigm in EV battery recharging, known
as a "flow" cell is in the works. Per this IEEE Spectrum magazine article,
one variation on the flow battery is one where spent electrolyte is replaced rather
than recharging the battery. "Flow batteries are safe, stable, long-lasting, and
easily refilled, qualities that suit them well for balancing the grid, providing
uninterrupted power, and backing up sources of electricity. This battery, though,
uses a completely new kind of fluid, called a nanoelectrofuel. Compared to a traditional
flow battery of comparable size, it can store 15 to 25 as much energy, allowing
for a battery system small enough for use in an electric vehicle and energy-dense
enough to provide the range and the speedy refill of a gasoline-powered vehicle."
When recharging - or replenishing more accurately - spent nanofluid is exchanged
for fresh nanofluid, which unlike lithium will not explode. The article does not
mention the transportation and processing costs (both monetarily and ecologically)
of making nanofluid available to tens of thousands of charging stations, including
home-based ones. Still, it's better than the Earth's growing lithium stain. BTW,
have you seen many EV charging stations with roofs over them? EVers get wet electrical
connections when it's raining.
Anritsu and EMITE OTA Measurements
on Wi-Fi 7
Anritsu Corporation and EMITE announce enhanced
functionality to their Over-the-Air (OTA) measurement solution, allowing measurements
in compliance with the latest Wireless LAN IEEE 802.11be standard. IEEE 802.11be
is being standardized as the successor to IEEE 802.11ax (Wi-Fi 6/6E) and is targeted
to realize high-speed communications that significantly exceed IEEE 802.11ax. The
standard is expected to be a fundamental technology supporting the latest applications
and services, such as ultra-high-resolution video streaming beyond 4K and AR/VR.
Anritsu's Wireless Connectivity Test Set MT8862A has been integrated with all
portfolio of EMITE Anechoic and Reverberation Chambers, allowing developers to measure
the OTA Total Radiated Power (TRP)/Total Isotropic Sensitivity...
Television in Germany
What's the big deal about
television in Germany, you might ask? Today, it is no big deal, but in 1937
when this article appeared in Popular Mechanics magazine, it was. Philo
Farnsworth and Vladimir Zworykin had only recently demonstrated their all-electronics
TV systems, and the battle was on to decide whether the electromechanical systems
that used rotating disks and/or mirrors, or the electronic-only types would emerge
victorious. Communications standards committees were evaluating and hotly debating
the pros and cons of each. Multiple all-electronic television system schemes contended
as well. Each country and/or area in the world generated their own set of standards,
so manufacturers who serviced worldwide markets needed to accommodate more than
one system. Shortly after B&W broadcasting finally settled out, color TV thrust
the industry and government regulators into another round of contentious competition.
This story reports on Germany's efforts to bring television to its citizens - as
it is preparing to start World War II...
RF Cascade Workbook
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...
Monday the 25th
Message from Apollo 8, Christmas Eve, 1968
While orbiting
the Moon on Christmas Eve, 1968, NASA astronauts Frank Borman, Jim Lovell, and William
Anders made a live broadcast from from the
Apollo 8
command module, in which they showed video of the lunar surface and the Earth as
seen from one of the spacecraft's portals. That flight produced the famous "Earthrise"
photograph which is featured on a U.S. commemorative stamp issued in May of 1969
- just three months before Apollo 11 landed on the moon. On the ninth orbit,
toward the end of the transmission, the three astronauts each took a turn reading
from the book of
Genesis, chapter 1, verses 1 through 10. They finished with,
"And from the crew of Apollo 8, we close with good night, good luck, a Merry Christmas
– and God bless all of you, all of you on the good Earth."
From Melanie and
me here at AirplanesAndRockets.com, we wish you all a very
Merry Christmas and a
happy and prosperous New Year!
Gilbert Erector Set from 1969 Sears Christmas Wish Book
On
page 511 of the Sears 1969 Christmas Wish Book are a few
Erector Sets. This was probably the year (±a couple) that I got my first Erector
Set. This was a step up from the Tinkertoy sets I previously owned. While not the
largest set made, it had quite a lot of parts, including a motor. Although I already
had a natural interest in assembling and - to my parents' dismay - disassembling
stuff, it was gifts like this that really helped nurture what would become a life-long
pursuit of things mechanical and electrical, eventually leading to my earning an
electrical engineering degree. I remember getting a pretty good finger pinch by
one of the motorize contraptions I built. Show above is Erector Set #3, similar
to the one I received for Christmas in 1969. This one I bought on eBay since, as
with most things I owned, the original did not survive my handling...
Many Thanks to Anatech Electronics
for Long-Time Support!
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.
Sunday the 24th
Electronics Theme Christmas 2023 Crossword Puzzle
This
Electronics theme Christmas Crossword Puzzle for December 24th has many words
and clues related to RF, microwave, and mm-wave engineering, optics, mathematics,
chemistry, physics, and other technical subjects, along with a holiday message.
There is also a holiday greeting contained within. 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!
Friday the 22nd
WWV's Sharp Tunes Keep World in Step
Back in the 1970s and 80s when I was a regular
reader of magazines like Popular Science, Mechanix Illustrated,
Popular Mechanics, et al, it never occurred to me that there were so many
stories and news tidbits related to electronics and communications. Now, half a
century later as I read through many of them, I am amazed to see just how much content
there is for posting on RF Cafe. Of course I was nowhere near as familiar with the
topics at the time, so the stories did not have the draw they do now. Just as with
the contemporary magazines I peruse each month, I typically go through them from
cover to cover, reading much of what is there, including the advertisements. This
1949 report is on the National Bureau of Standards' (NBS, now National Institute
of Standards and Technology, NIST) frequency and timing standard signals from their
original location near Washington, D.C., call sign
WWV. Details on the various continually broadcasted signals are covered within,
along with some of the equipment used to accomplish the feat. You will need to visit
the current WWV website to compare with today's signals...
Terminal Radio Christmas and New Year Greeting
Other than today's QST magazine
being a larger format and being printed in full color, there is not much difference
fundamentally between the amount of
Christmas-themed company advertisements now and half a century ago. The
January 2024 (out now) issue of QST is chock full of Christmas-themed
ads. Those from the last century were more likely to incorporate a religious message
in addition to or instead of a secular message to their customers. Terminal Radio
Corporation was located in midtown Manhattan. Google Maps can find West 45th Street
and it can find Cortlandt Street, but they evidently no longer intersect. Many component
supply companies were located in New York City because it was a primary point of
import and export of manufactured goods...
Please Thank IPP for Their
Long-Time Support!
Innovative Power Products has been designing
and manufacturing RF and Microwave passive components since 2005. We use the latest
design tools available to build our baluns, 90-degree couplers, directional couplers,
combiners/dividers, single-ended transformers, resistors, terminations, and custom
products. Applications in military, medical, industrial, and commercial markets
are serviced around the world. Products listed on the website link to detailed mechanical
drawings, electrical specifications, and performance data. If you cannot find a
product that meets your requirements on our website, contact us to speak with one
of our experienced design engineers about your project.
The Christmas Equation
An RF Cafe visitor sent this equation to
me a few years ago. It can be found all over the Internet (including here), but
I cannot determine a definite origin. Mathematicians claim that math can explain
everything in the universe, which is not quite true. It can't for example, explain
why my next-door neighbor is a junk hoarder. This
Christmas equation
does not appear to begin with a particular application; it looks like something
from a set of textbook end-of-chapter problems. Even if you don't celebrate Christmas,
it provides a secondary benefit by demonstrating rules for the manipulation of logarithms
and exponents along with basic algebraic rearrangements of terms.
After Class: Resistor and Capacitor Combinations
Here is a short tutorial on
resistor-capacitor (R-C) combinations and the time constants created by their
combinations. It's pretty basic stuff, but there are new people coming into the
field of electronics all the time so it is worth posting. Discussed are coupling
circuits, filter networks, differentiators, and time-delay circuits. The "After
Class" feature is a series run by Popular Electronics magazine in the 1950s
and 1960s. As with this installment, "After Class" presented topics on electricity
and magnetism that served not just as new material for beginners, but was a good
review even for seasoned practitioners of the craft. A complete list of all the
"After Class" articles I have posted is listed below...
Thanks to TotalTemp Technologies
for Continued Support!
TotalTemp Technologies has more than 40
years of combined experience providing thermal platforms.
Thermal Platforms are
available to provide temperatures between -100°C and +200°C for cryogenic cooling,
recirculating & circulating coolers, temperature chambers and temperature controllers,
thermal range safety controllers, space simulation chambers, hybrid benchtop chambers,
custom systems and platforms. Manual and automated configurations for laboratory
and production environments. Please contact TotalTemp Technologies today to learn
how they can help your project.
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.
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while tying up your telephone line, and a lady's voice announced "You've Got Mail"
when a new message arrived...
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