Engineers are entirely comfortable with numbers
multiplied by very large powers of 10; that is, with many trailing (or leading if
a decimal) zeros after the significant figures. A terahertz is 1 x 1012,
or 1 followed by twelve zeros, or
1,000,000,000,000. A picosecond is 1 x 10-12, or eleven zeros between
the decimal point and the one, or 0.000000000001. The mass of the sun is approximately
1.9885×1030 kg, or 1,988,500,000,000,000,000,000,000,000,000 kg.
The mass of an electron is approximately 9.10938×10−31 kg, or 0.000000000000000000000000000000910938 kg.
We don't even break a sweat when punching those kinds of numbers into a calculator.
We're used to it. When most laypeople these days hear politicians nonchalantly toss
around figures in the trillions of dollars regarding a country's deficit or planned
new spending packages, or the net worth of Amazon's Jeff Bezos, Tesla's Elon Musk,
and Donald Trump, they have no concept of how big the numbers are...
RF Cave visitor and contributor
Joseph Birsa (N3TTE), sent me a note about yet another edition of a
special purpose catalog published by Sears - the
Sears 1940 Amateur Radio, Test Equipment, Sound System Catalog. A
little research revealed that it was actually an extended version of the
1940 Sears, Roebuck and Co. Superior Amateur Equipment and Radio Service
Supplies - 64 versus 48 pages, respectively. Even the standard edition
Sears, Roebuck Fall 1941 Catalog contained a large section dedicated to
radios and equipment. The cover on the shorter catalog makes me think of
The Radio Boys series of books, where a cadre of four early 20th century
teenagers experienced adventures centered around build and operating
wireless equipment. Hallicrafters, National Company, Meissner, and
Hammarlund receivers and transmitters were offered for sale. Bliley and
When doing some research for creating
a new quiz on inventors and
their inventions, I decided to look for people according to their countries.
I almost always do image searches since doing so does a good job of filtering
out pages that merely mention the topic of interest. My first Google search
was "american inventors." I expected to see the familiar faces of Thomas Edison,
Henry Ford, George Westinghouse, Marie Curie, Alexander Graham Bell, George
Washington Carver, Edwin Armstrong, Hedy Lamarr, Benjamin Franklin, Robert Goddard,
Albert Einstein, the Wright Brothers, Samuel Morse, William Shockley, etc. Those
are the names that first come to my mind, and admittedly the list is dominated
by White men. Imagine my surprise when the Google search results belied my perception.
Take a look at the first few pages of results to see what I mean. Next, I moved
on to an image search for "canadian inventors..."
As our traditions are besieged by malcontents
determined to denigrate, impugn, and ultimately erase memories of holidays and
events that have meant so much to families and friends, I feel compelled to
resist the movement by documenting parts of the past that will cause us to wax
nostalgic over our cherished traditions. Intimidation and violence is part of
the strategic calculus; we have seen it in spades in 2020, and 2021 promises
to be even worse. The Cancel Culture might eventually win out with the complicity
of government agents both elected and unelected, but I'm not going down without
a fight. Here is a collection of twentieth century, December issue
covers with Christmas themes that will no doubt be familiar to many of you.
Finding them was more difficult...
December 24, 2020
RF Cafe visitor Michael Maassel, an electrical
engineering professor in North Dakota State University's Electrical and Computer
Engineering Department, requested that I post these few questions to help him
effectively prepare students taking senior-level (aka "Capstone") design courses
for a real-world experience after graduation. Says the good professor, "The
biggest headache I have is getting the students to
document their work, both in hardware and in software. Currently, I am requiring
that the students use a quad line notebook. This has not been very successful."
How do you handle documentation in your every-day work?
For many years Melanie and I have been
collecting and reading
The Radio Boys
series of thirteen books, which were written in the 1920s by Allen Chapman.
It was a time in history when the miracle of radio communications was capturing
- even enrapturing - the public with its seemingly miraculous ability to convey
messages across town and around the world without the need for wires, hence
"wireless." The stories center around four teenage buddies, namely Bob Layton,
Joe Atwood, Herb Fennington, and Jimmy Plummer (aka Doughnuts") who, with the
assistance of a local pastor, Dr. Dale, took an avid interest in radio and built
from scratch a successful crystal radio. Their enthusiasm compounds upon itself
as adventures and experiences using wireless foster interest in building better
receivers and then building transmitters for sending Morse code and audio ("phone").
In order to appeal to his intended audience - primarily young boys - villains,
good guys, hapless bystanders, government agents, local law enforcement, family,
and even the occasional damsel in distress...
About a decade ago, photos began appearing
on news websites showing Chinese citizens walking around
wearing face masks in order to filter out the massive air pollution pouring
from city factories and coal-fired electric power generation plants. Articles
were written advising on the best types of face masks to use while visiting
or working in China. The only topic about China competing for shock factor at
the time was the rash of suicides at Foxconn as the poor soulless, hopeless
workers who build our inexpensive electronics products jumped from upper factory
windows and roofs. Since around March of this year, nearly every location in
the United States and around the world is looking like China did for the entire
last decade. A worldwide pandemic was declared because of a deadly virus which
originated from the Wuhan area of China...
Have I mentioned that my YL, Melanie,
decided she would earn her Amateur radio Technician license? After living in
a household with a bilingual husband (English and Electronics) for nearly 38
years and having become fairly proficient at ETL (electronics as a third language*),
Melanie decided to earn her Technician license. She has never delved into the
technical aspects of electricity / electronics, but has, along with hearing
me speak of it (too) often and having proof-read my writings and scanned and
OCR'ed more than a thousand articles from vintage electronics magazines, her
gray cells are permeated with the vocabulary, lingo, jargon, vernacular, slang,
and argot of the realm. Being an expert test taker, she will undoubtedly pass
the written test with flying colors. With much self-restraint, I have avoided
offering my sage advice and knowledge during her studies of the ARRL's Ham
Radio License Manual. The current edition is the 4th, being valid from
2018 through 2022. Melanie has asked for a little clarification on SWR, decibels
and couple other minor topics, but otherwise has progressed...
The world was introduced publically
in 2007 to the concept of a 3-dimensional Smith chart by Chris Zelley.
In article published in IEEE Microwave Magazine entitled, "A Spherical Representation
of the Smith Chart," the radically new concept was illustrated on the surface
of a ping pong ball using a felt-tipped pen (thumbnail at left). Inspired by
the sight, Andrei A. Muller and a small team of developers in 2013 created a
version of the
3D Smith Chart in software using the Java language that allows it to execute
on any platform. In 2017, an expanded functionality commercial version of 3D
Smith Chart was released at a very modest price. A number of articles have been
published on the topic extolling the unique ability of a 3-dimensional complex
impedance volume to expose...
The other day a song entitled "Western Union" played
on my local over-the-air oldies radio station. It was released by the group
The Five Americans in 1967. I've heard it many times before, but it finally
occurred to me that the use of Morse code-like symbols in the refrain made it
a perfect candidate for a spot here on RF Cafe. The full lyrics of "Western
Union" can be found at the bottom of the page, but notice the "Dah-Dit-Dah-Dit-Dah"
repeats in the refrain. Even though I'm a licensed (as of 2010) Ham, my shameful
(according to some veterans) status as a post-Morse-code era did not require
demonstration of code proficiency. As such, my lack of a Morse code deciphering
ability required that I rely on an online translator for considering what the
code might be. Depending on how you separate the dits and dahs, the string of
characters can be interpreted as TETET (- . - . -), TAA (- .- .-), KA (-.- .-),
NK (-. -.-), CT (-.-. -) or other combinations, none of which seem to mean anything
A couple years ago a house two streets
away had an estate sale after the elderly gentleman who owned it passed on.
There was a lot of old
gear for sale, and most of it had been bought early in the morning, right
after the beginning of the sale according to the man's daughter who was on-hand.
The newspaper notice mentioned the Ham equipment. In the back yard was a nice
40-foot crank-up tower that was a bit weather-worn, but otherwise appeared to
be in good condition. She said that was the first item sold. I didn't ask how
much she got for it. The house was to be sold, and they were glad to have the
tower gone before listing it on the market. I have wondered in the past when
seeing a "For Sale" sign in the lawn of a house with one or more radio towers
in the yard how much they would impact the sale price. Some Hams would plan
Lincoln Vocational Technical Center.
One day in late spring of 1973 I found myself walking around the gymnasium of
Annapolis Junior High School (AJHS) trying to decide which courses I would prefer
upon beginning tenth grade the following fall. It was one of the final days
of ninth grade, which had been by far my least happy year in school. Living
in Mayo, Maryland, I and my fellow neighborhood ninth graders should have attended
Southern Senior High School (SSHS) in Harwood, Maryland, where our predecessors
had gone for ninth grade, but overcrowding caused the Anne Arundel School Board
wizards to decide that for at least that year, we would remain at AJHS for another
term. Historically, kids from my area went to AJHS only for seventh and eighth
grades and then switched to SSHS. Annapolis, being the capital city of Maryland,
was significantly more urban than the rural areas which SSHS type people were
accustomed to. The clientele was much more aggressive in the big city. Sure,
we had our "red neck greaser" rowdies in the southern part of the county, but
at least their parents would whip them if they got caught getting into trouble.
The north county parents, we believed at the time...
If you are annoyed by
pop-ups and extraneous framework elements and/or SEO (search engine optimization)
tracking code accompanying application notes, white papers, and images, and
videos, many times you can get rid of them by editing the URL displayed in your
browser address bar. Compare the displays in this set of screen captures based
on the original URL provided in an e-mail (top) to the one where all the extraneous
terms have been removed from the URL (bottom). Note that the yellow highlighted
components have been eliminated. Often, I remove that stuff from hyperlink URLs
before sending my visitors to websites. Companies don't particularly like me
doing that, but doing so helps maintain your privacy. URLs in e-mails are particularly
likely to contain appended code that contains one or more "&utm_" parts.
UTM is the Urchin Tracking Module introduced by Google Analytics' predecessor
Urchin and are now supported by Google Analytics. They typically ....
Miscellaneous Earlier Smorgasbords and Factoids: