Today in Science History -
ASCII Art has been around nearly as long
as digital computers have been in existence. It was the only type of "graphics"
available to most users before other than text displays were commonplace. Universities,
corporations, and government research facilities had crude forms of graphical displays,
but it was not until the 16-color, 640x200-pixel CGA (Color Graphics Adapter) monitors
began shipping with IBM PCs that most people had access to "real" graphics. To compensate,
some pretty clever souls came up with what has become known as "ASCII Art." ASCII
(American Standard Code for Information Interchange), for those of you too young
to remember when that was part of common computer parlance, is the basic set of
numbers, letters, and special characters that all computers are capable of rendering
based on unique codes assigned to them. For instance, ASCII character 48D (30H)
is the number "0," 65D (41H) is upper case "A,"...
Edwin H. Armstrong demonstrated the viability of FM (frequency modulation) for
long distance broadcasting in January of 1940, the U.S. FCC (Federal Communications
Commission) allocated spectrum to it in the 42-50 MHz band. Armstrong had introduced
the FCC to FM originally in 1936. The new modulation scheme was popular due to its
immunity to amplitude related noise like that generated by motors, automobile ignition
systems, and lightning. However, World War II broke out a little over a year
later and most commercial radio advancements were put on hold. This article from
a 1940 edition of National Radio News could not have predicted that, or the FCC's
decision to relocate the FM spectrum to 88-108 MHz in 1945 in the closing days
of WWII. Some speculate that the spectrum shift was a ploy by RCA chairman David
Sarnoff to undermine the advantage Armstrong had with his established FM radio production.
Nah, it couldn't be so because government bureaucrats...
EE Times has a tribute to Fairchild
Jay Last following news of his passing at age 92. "One of the least-well-known
heroes of the semiconductor revolution, Jay Last, died on November 11, 2021. Last
was one of the famous team of eight people that left
Semiconductor Laboratory to found Fairchild Semiconductor. While there, he was
leader of the team that developed the essential technologies that led to the first
practical IC. In 1946, between his junior and senior years in high school, Last
hitchhiked from Pennsylvania to the orchards of San Jose, Calif., where he picked
fruit for the summer. It was probably a lark at the time, but a momentous decision
nevertheless. After earning a PhD in Physics from MIT in 1956, he ended up moving
to the San Francisco Bay area to work at Shockley Semiconductor Laboratories in
Palo Alto, California. His fruit-picking experience influenced his decision to move
to California. Shockley Semiconductor was founded in 1956 as a Beckmann Instruments
subsidiary. At the time Last was wrapping up his doctoral thesis, working with a
balky Beckman spectrophotometer, which led to plenty of interactions with Beckman’s
"NASA plans to launch a pair of laser communications
missions over the next nine months that would demonstrate high-bandwidth optical
relays capable of someday transmitting streaming HD video and other data from planetary
probes. The launch of the
Laser Communications Relay Demonstration (LCRD) scheduled for Dec. 4 will be
followed as early as August 2022 by the launch of the Deep Space Optical Communications
flight demonstration, program officials said this week. LCRD, testing laser communications
from geosynchronous orbit, is managed by NASA's Goddard Space Flight Center. The
Jet Propulsion Laboratory (JPL) is overseeing development of the deep space mission
that will operate between the orbits of Mars and Jupiter as part of NASA mission
to study a giant metal asteroid..."
Things are looking up for
RFCafe.com website statistics.
The trend lines for Page Views, Visits, and New Visits all have a positive slope.
I have put a lot of effort into making pages compliant with Google's "Mobile Friendly"
requirements, so that probably has something to do with it. Also, you may have noticed
that I have been modifying and re-publishing some of the earlier RF Cafe webpages.
That involves updating the narrative, verifying hyperlinks (many go dead over time),
and cleaning up older graphics. Much has changed in expectations from visitors -
especially from the early days in the late 1990s and early 2000s. Competition for
visitors is fierce. As always, thank you for your visitorship and stewardship.
Magnetrons and klystrons are fairly ubiquitous
in society these days for use in heating, radar, industrial processes, cooking,
and even lighting. They were probably the first useful means of producing high power
microwave signals. The concept was first brought to fruition in the early 1920s
as a laboratory curiosity and rapidly developed into a practical type of device
with many applications and spin-off products like the klystron, the traveling wave
tube, and the cross-field amplifier. This article from a 1932 edition of Radio News
magazine reports on the state of the art a decade after the magnetron's inception...
New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website visits each weekday.
RF Cafe is a favorite of engineers,
technicians, hobbyists, and students all over the world. With more than 16,000 pages
in the Google search index, RF Cafe returns in favorable positions on many
types of key searches, both for text and images. New content is added on a daily
basis, which keeps the major search engines interested enough to spider it multiple
times each day. Items added on the homepage often can be found in a Google search
within a few hours of being posted. I also re-broadcast homepage items on LinkedIn.
If you need your company news to be seen, RF Cafe is the place to be.
TotalTemp Technologies has more than 40 years
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Hobbyists in the technical realm have in
many ways contributed mightily to the advancement of professional scientific knowledge
and practice. This is partly because many hobbyists are also career technologists,
but the majority are tinkerers, experimenters and otherwise participants who come
from all walks of life geographically, economically, professionally, and socially.
Just as with university and corporate laboratories, some of the discoveries are
the result of structured, preconceived plans of action and designs of experiments
with certain goals in mind; many, however, are due to serendipitous events that
are recognized by their participants as being significant. Such is the case of "TV DX"
as related in this story. TV DX is the use of unique opportunities in the atmosphere's
ionization state to facilitate signal transmission and reception at distance much
greater than normally experienced. Data collected by amateurs were, during the era
of over-the-air VHF and VHF television broadcasting, included in studies and theories
created by professional scientists and engineers...
Anyone who watched the
WKRP in Cincinnati
sitcom back in the 1970s has to remember what was one of the funniest episodes ever.
Here is the 4 minutes that made Prime Time history. In this Thanksgiving episode,
station owner Arthur Carlson decided he would surprise the community with good deed
- that doubled as a promotional stunt for his radio station - by dropping turkeys
from a helicopter for lucky shoppers at the local shopping mall. Watch the disaster
unfold as Les Nessman reports live, and then see Carlson's final comment that is
still used or alluded to in many comic routines. Posting this video is an RF Cafe
tradition. Have a Happy Thanksgiving!
"The Air Force Research Laboratory has awarded
Utah State University a $1B contract to support
space-related research and technology development at its Space Dynamics Laboratory.
Under the contract, the Space Dynamics Laboratory will continue to provide an outside
source for essential space engineering and capability development as a University
Affiliated Research Center, or UARC. 'This contract solidifies the long-term strategic
partnership between AFRL and USU/SDL. The partnership will accelerate critical space
science and technology projects, especially when we need to quickly respond to urgent
and unexpected needs,' said Col. Eric Felt, director of the AFRL Space Vehicles
Directorate, in a statement. 'It will allow us to focus on proactively out-innovating
our peer competitors to ensure the Space Force continues to have the technology
required to deter conflict..."
Well, no, but then who really is? Thanks
to vigilant and brilliant scientists and engineers developing detection and protection
schemes, mankind has survived some fairly significant solar storms (primarily coronal
mass ejections - aka
CMEs) which might
have profoundly disturbed and/or destroyed some vital communications and electrical
distribution capabilities. As with all the behind-the-scenes work that prevented
a Y2K catastrophe,
most people are not aware of immense effort put into safeguarding mankind against
such natural perils. An EMP is a different beast, though, because it would be a
manmade electrical disturbance, likely as an act of war. Survivalists think owning
an old pickup truck without any electronics in it and a vacuum tube radio is the
key to surviving an EMP. It wouldn't be long before they were in the same doodoo
as the rest of us if a major EMP event occurred. If you worry about such things,
here is an article on the Electronic Design website that might interest
you entitled "Are
You Prepared for an EMP?"
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!
Innovative Power Products (IPP) has over
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and attenuators are fabricated using the latest materials and design tools available,
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to visit their website and see how IPP can help you today.
The virtues and evils of the plethora types
television antennas was the subject of many magazine articles back in the era
preceding cable, Internet, and satellite program delivery methods. Over-the-air
broadcasts, while available free of cost to recipients, were often fraught with
signal and therefore picture and audio degradations due to signal blockage, reflection,
and multipath issues. How people dealt with the problems was also the theme of many
TV-related comics which also appeared in those magazines. Serious efforts were made
by engineers and homeowners to remedy those problems through a combination of antenna
design, mounting, amplification, cabling, and other methods. Of course there were
also the crazy "solutions" which involved tin foil over, between, and around VHF
rabbit ears and/or UHF loops and other things. I must also admit to having also
resorted to extreme measures...
Indoor Television Antennas
This second in a series of
International Geophysical Year (IGY) articles that appeared in Radio-Electronics
magazine in 1958. The author covers basics of satellite configuration, launching,
and tracking based on knowledge of the era. Keep in mind, though, that the U.S.
had not actually launched its first satellite at the time. In fact, the two satellite
models shown possess antennas suggesting active radio circuits within, but Echo,
our first passive earth-orbiting satellite, was just a metallized plastic sphere
that reflected radio signals back to Earth. The Russian Sputnik, by comparison,
did have electronic circuitry onboard for transmitting but not receiving a signal.
SCORE, launched in December of 1958, was America's first transponder satellite...
Anatech Electronics offers the industry's
largest portfolio of high-performance standard and customized
RF and microwave filters and filter-related products for military, commercial,
aerospace and defense, and industrial applications up to 40 GHz. Two new filter
models have been introduced - a 896-898 MHz / 935-937 MHz cavity duplexer,
a 2400 MHz ceramic bandpass filter with sharp roll-off above and below the
pass band, and a 300-320 MHz / 360-380 MHz LC duplexer. Custom RF power
directional coupler designs can be designed and produced when a standard cannot
be found, or the requirements are such that a custom approach is necessary...
A few new terms have been added to the
transistor lexicon since 1958, but this list from Radio-Electronics
magazine contains more than 150 definitions that are still useful today. It is amazing
that this list was created just a decade after the transistor was invented, and
now half a century later the most commonly used terms have not changed much. In
looking over the words, there are very few that need to be added to the original
(which I did)...
Here are a few more electronics-themed comics
from magazines of the days of yore. Radio-Craft readers submitted ideas
for funnies and then artist Frank Beaven would draw the comics based on their ideas.
Some months had no comics, and others had half a dozen or more. This June 1945 issue
had three. There is also one from the May 1946 Radio News. You website
visitors not familiar with vacuum tube construction might need to know that the
jailhouse bars in "Control Grid" comic are an allusion to the wire mesh type element
in tubes that modulated electron flow from the cathode to the anode. I once again
colorized the comics to make them more attractive. Enjoy.
In case such things interest you, this first-person
story of a
wireless operator, or "op," - the guy who manned the radio room - provides a
little entertainment and insight into transoceanic travel in the 1930s. Per this
1932 Radio News magazine article, the author's trip was made less than
two decades after the demise of the "unsinkable" RMS Titanic, where surviving passengers
and crewmen were saved partially due to the heroics of the telegraph operators.
Having never traveled on the water beyond the Chesapeake Bay, I wouldn't know how
to compare today's voyage with those of yesteryear. Do passenger ships nowadays
sometimes idle for three weeks in Central American waters while waiting for passage
through the Panama Canal? Can anyone identify the story's ship shown in the photo?
Evidently Griffin was not permitted to name it because of the less than totally