Computer analysis in 1976 was a job performed
on a corporate, university, or government mainframe. Radio Shack's TRS-80 came out
in 1977, but it did not have the capacity to calculate and plot antenna gain charts
like the one in this QST article. Yes, an ambitious programmer could write
the code necessary to perform the double integrals presented in the article, but
to do all the figuring needed to create all the graphs in Figure 4, the job would
just about be finishing up today - and that's not too much of an exaggeration. For
some reason the authors never mention what computer was used or where it was based.
When I saw the title of "Loops vs. Dipole,"
I expected the loop to be...
If I told you that Lester William Polsfuss
is widely credited with being a major player in the pioneering of electric guitars
due to his solid-body (no acoustic resonance chamber) designs, you might wonder
where I came up with that claim. However, if you know that Mr. Polsfuss is the surname
of Les Paul, then you would quickly agree. As if being a popular musician and, along
with wife Mary Ford, selling millions of records wasn't enough, Les Paul was also
an experimenter and inventor in the electronic music realm. This article entitled
"Les
Paul: Technician and Musician" appeared in a 1958 article in Radio-Electronics
magazine, and was at the time a contemporary look inside his...
Even with having been granted more than
400 patents in his lifetime, and being a major player in the realms of energy, data
storage, and semiconductor research and manufacturing, you - as well as most people
- have probably never heard the name
Stanford Ovshinsky. He was somewhat of a celebrity in the 1960s and 1970s when
working hard to promote his concept of "glassy semiconductors," - aka Ovonic devices.
Ovonics are amorphous materials that are used for making switches for digital logic
and memory devices. Either the Ovshinsky process did not pan out for high volume
commercial production or some other technology displaced the what it was hoped to
dominate...
One of the Notable Tech Quotes which has
appeared on RF Cafe is, "The nice thing about standards is that you have so many
to choose from," by computer scientist Andrew Tanenbaum. In the middle of the last
century, a change in the fundamental understanding of current flow precipitated
what has become a very large opportunity for people to misunderstand descriptions
of
current direction caused by a difference in voltage potential (voltage) - depending
on the era a particular description was written. Beginning with Benjamin Franklin,
electron current flow was assumed to be from positive to negative, ostensibly but
incorrectly, because a positive thing must contain an excess...
The "Monthly Review" column appearing in
Radio-Craft magazine was an assorted collection of news tidbits about
electronics and communications industry happenings, similar to contemporary
magazines. Looking back to 1947, the world was hopeful about the future as World
War II was finally over and even the loser countries were focusing on how their
societies would be shaped by technology and lessons learned in the preceding seven
to ten years (depending on when a country entered the war). Two items here are particularly
interesting because they refer to ongoing research into large screen televisions
and video phones (aka "televisers"). Large screens at the time meant either...
Since the International Microwave Symposium
(IMS 2020) is completely virtual this year, I figured maybe re-posting my coverage
of the
Microwave
Museum display of vintage industry research and development items would fit
right in. The photos were taken during my attendance at IMS 2009 in Boston,
MA. At the time, they were the only photos of the collection on the WWW. It had
a very nice display of items from the early days of radio and radar. According to
the IMS 2009 website, the items are "memorabilia from the first IMS held in Boston
50 years ago." Most displays were glass cases, so it made getting useful photographs
difficult because of glare and reflections. You will see...
If you think electric cars are a new idea,
read on. I saw this article, "The Amazing
Collection in Thomas Edison's Garage," on another website (the equivalent of
Jay Leno's Garage from a century ago) and thought it was a special report,
but then I noticed it was actually a paid promotion. So, I contacted the company,
B.R. Howard & Associates, Inc., asking for permission to re-post it in its entirety
on RF Cafe. They kindly agreed to it. Per their mission statement: "Our company
focuses on the conservation of historic artifacts in accordance with the principles
defined in the American Institute for Conservation of Historic and Artistic Works
Code of Ethics and Guidelines for Practice." Their...
After reading so many articles about vintage
vacuum tube radios and TVs in the older electronics magazines, it makes me appreciate
the relatively trouble-free products we enjoy today thanks to semiconductor technology.
Monthly columns were filled with troubleshooting advice and tips for making modifications
to factory designs that will enhance performance and/or reduce the likelihood of
premature failure. Although many tubes did outlast the lifetime of the chassis in
which they were installed, it was pretty much a given expectation that sooner or
later some
tubes would need to be replaced - that is why they were the only components
that came installed in sockets for easy removal ...
Most Ham radio operators know that Franklin
D. Roosevelt issued an order during World War II that effectively suspended
the hobby of amateur radio for the duration of the war. Many guys sold or donated
equipment to the military and/or civil defense organizations out of a sense of patriotism.
The
Radio Corporation of America (RCA) gave a symbolic tip of the hat to them in
this advertisement that I scanned from the back cover of my copy of the April 1945
QST magazine. Of course RCA pitched the ruggedness of its vacuum tubes
in the process. By this edition's printing, there was a general sense that the war
was nearing an end and eager Hams would not have to wait much longer to reengage...
This custom
Communications Engineering crossword puzzle contains some words particular to
radio, radar, analog and digital circuits, components, and other tech-themed words
and clues. Each week for two decades I have created a new technology-themed crossword
puzzle using only words (1,000s of them) from my custom-created lexicon related
to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will
never find among the words names of politicians, mountain ranges, exotic foods or
plants, movie stars, or anything of the sort. You might, however, find someone or
something in the otherwise excluded list directly related to this puzzle's technology
theme, such as Hedy...
Frequent RF Cafe visitor who goes by the
moniker "Unknown Engineer" sent me a hyperlink to a PDF file on Amazon's CloudFront*
content delivery network (CDN - basically a file server) that contains no fewer
than 17 amazing radar and vacuum tube related line
drawings
published by Varian Associates' TWT Division, Palo Alto Tube Division, Solid
State Division, Eastern Tube Division, Western Tube Division, Solid State West
Division. These highly detailed and busy drawings were done around 1975 by
British illustrator/artist C.E.B. Bernard; a search for his works did not reveal
much. The events shown are fictitious, as are the accompanying hand-printed
stories. Some of the puns...
Before the days of cheap stuff from China,
the supply of most common items- particularly high technology - were the domain
of relatively few companies. In some ways it was not entirely a bad thing because,
at least theoretically, the economy of scale enabled larger producers to leverage
bulk buying, well-equipped development labs and manufacturing equipment, and pooling
of talent resources to sell quality products at a lower price. Of course it required
that the company had serious competitors or monopolistic tendencies resulted in
gouging - it's human nature, unfortunately. Hewlett Packed, as much as I appreciate
what the company did for
electronics test equipment, had gotten...
Breaking news from May 1958: "Hardly a month
passes nowadays without the announcement of some 'sensational' new amplifying device.
The great majority of these startling inventions, after their brief flurry in the
popular and technical press, disappear into oblivion. But we believe that the
Tecnetron, just announced in France, has a brilliant and enduring future." Have
you ever heard of a Tecnetron? I didn't think so; neither had I before reading this
article in Radio-Electronics. I guess that pretty much negates the preceding prediction.
The holy grail of the Tecnetron, whose etymology in and of itself is worth reading
about (it's not what you would guess), is that its transconductance increases with
frequency. Construction is such that although it is fabricated from a shaped rod
of germanium, it has a current controlling component that acts like a cross between
a triode vacuum tube and a depletion mode field effect transistor. My guess is that
the rapid improvement of standard semiconductor junction field effect transistors
rendered...
This April 26, 2020,
tech-themed crossword puzzle is bigger than most, figuring that unfortunately
many people have more time to kill due to the situation described in the sentence
formed by 5 Down, 8 Down, 44 Down, 74 Down, 77 Down, and 80 Down. Otherwise, it
contains only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc., which I have personally built over nearly two decades.
Many new words and company names have been added that had not even been created
when I started in the year 2002. You will never find a word taxing your knowledge
of a numbnut soap opera star or the name of some obscure village in the Andes mountains.
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.
Meteor (burst) scatter communications is
an excellent example of where hobbyists - in this case amateur radio operators -
have contributed mightily to technology. It could be argued that a big part of the
reason for such occasions is that many people involved in science type hobbies are
employed professionally in a similar capacity, and their extracurricular activities
are a natural extension of what pays for the pastimes. It seems amazing to me that
meteor scatter as a means of achieving upper atmosphere reflections of radio signals
went undiscovered until 1953, but evidently that is the case. Meteor scatter is
a very popular form of amateur radio challenge these days, with much activity when
the bigger meteor showers are underway. Prior to 1953, meteor shower study was the
sole domain of astronomers...