See Page 1 |
2 |
3 |
4 of the November 2021 homepage archives.
Tuesday the 30th
Here is the final installment
of C.W. Palmer's "Microwaves"
series of article in Radio-Electronics magazine. Topics for all seven parts
are shown below. Unlike the previous parts, this one discusses uses for waveguide
below its cutoff frequency for switching and attenuation purposes. Of course there
is also the filter application as well which exploits the high attenuation in the
cutoff region. Since these pieces were written in the pre-solid state semiconductor
era, vacuum tubes appear as control and amplifier devices rather than diodes and
transistors, but don't let that deter you from benefitting from the useful waveguide
characteristics lessons presented...
"Princeton University researchers have taken
a step toward developing a type of
antenna array that could coat an airplane's wings. The technology, which could
enable many uses of emerging 5G and 6G wireless networks, is based on large-area
electronics, a way of fabricating electronic circuits on thin, flexible materials.
The approach overcomes limitations of conventional silicon semiconductors, which
can operate at the high radio frequencies needed for 5G applications but can only
be made up to a few centimeters wide and are difficult to assemble into the large
arrays required for enhanced communication with low-power devices. With an airplane,
because its distance is so far, much signal power is lost. Since wings are a fairly
large area, a single-point receiver on the wing does not help but if the amount
of area..."
Magnetron, photomultiplier, traveling wave,
compactron, klystron, backward wave, pencil, lighthouse, cathode ray, indicator,
nuvistor, acorn, peanut, T-R, electrostatic, cat's-eye, orithon, and loctal, are
just a few of the many types of vacuum tubes that have been and in some cases still
are in use in various types of electronic equipment. Some you have heard of, others
you probably have not. All are discussed in a series of three articles published
in Popular Electronics magazine. This is part 3, which includes operational
descriptions of
klystrons, magnetrons, and traveling wave tubes (radar & satellite communication),
all of which are still designed into new products today...
Exodus Advanced Communications' new model
AMP2136P-4KW is a 2.0-4.0 GHz, 4 kW pulse amplifier that is designed
for pulse/HIRF, EMC/EMI Mil-Std 461/464 and radar applications. Other frequency
ranges & power levels available - all providing superb pulse fidelity. Up to
100 μsec pulse widths, up to 6% duty cycles with a minimum 66 dB gain.
Available monitoring parameters for forward/reflected power in watts & dBm,
VSWR, voltage, current, temperature sensing for outstanding reliability and ruggedness
in a compact 10U chassis...
For some inexplicable reason I went backwards
on this three-part
Tube Family Tree series that appeared in Popular Electronics. Author
Louis Garner, Jr., starts out with the early history of vacuum tubes, beginning
with Thomas Edison's incandescent light bulb and then quickly progresses to Lee
de Forest's Audion amplifier tube, and on through the evolution of multi-grid vacuum
tubes that are specially designed for low noise receiver front ends, high power
transmitters, voltage and current regulators, video cameras, pulse forming networks,
traveling wave tubes, and many other types. There is quite a bit of information
and history contained in these three installments that will do a very nice job of
introducing you to the wonder... Here you can read
Part 1,
Part 2 and
Part 3
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...
Please take a few moments to visit the
everythingRF website to see how they can assist
you with your project. everythingRF is a product discovery platform for RF and microwave
products and services. They currently have 267,269 products from more than 1397
companies across 314 categories in their database and enable engineers to search
for them using their customized parametric search tool. Amplifiers, test equipment,
power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers,
power supplies, and everything else. Please visit everythingRF today to see how
they can help you.
Monday the 29th
"The
Radio Month" news column from the November 1949 issue of Radio-Electronics
magazine contained much interesting information. At the top of the list was an announcement
that an all-electronics system for color television implementation had been presented
to the FCC. It was one of three such systems vying for official adoption as an industry
standard. CBS (Columbia Broadcasting System), CTI (Color Television, Inc.), and
RCA (Radio Corporation of America) were in stiff competition. Here is a January
1951 Radio-Electronics article describing the three systems. Ultimately,
the NTSC forged its own standard that incorporated an all-electronic system that
was also backward-compatible with the existing black and white (B&W) system.
Also included was information about the first Philadelphia Radio Service Men's Association
(PRSMA) meeting. It was sort of an IEEE for electronic service technicians...
Now that the inestimable Bob Pease is no
longer with us to enlighten and entertain, is there a contemporary and immediately
recognizable electronics technology name you see on a magazine article, book, or
presentation? Maybe my tech literary world is pretty small, but nobody come to mind
as I write this (apologies to the many great authors I am forgetting). In the early
part of the last century, you can be sure that when the names Edison, de Forest,
Tesla, Marconi, Bell, and Morse were featured in bylines, readers took note.
Lee de Forest's 1945 article in this 1945 Radio-News magazine
on the state of the art of television was an example. No doubt many reports on TV
were written, published, and passed over, but when one of the Greats of the industry
put pen to paper it will be noticed. It worked with me...
Here is a major paradigm change from Apple's
traditional "No user serviceable parts inside" philosophy. "Apple said it plans
to launch a
self-service repair program in 2022 that would allow consumers for the first
time to fix their own iPhones and Macs with Apple parts, tools, and manuals, a prominent
shift in the consumer electronics giant's stance on the repair process. The new
Self Service Repair program will be available first for the company's most recent
iPhone 12 and iPhone 13 lineups in early 2022. It will later expand to Mac computers
featuring Apple's M1 processors, the company said on Wednesday. Under the new program,
customers will be able to fix their own devices, starting with the display, battery,
and camera modules in the iPhone, using genuine parts, tools, and repair manuals
distributed by Apple..."
This is another Radio Service Data Sheet
that appeared in the May 1936 edition of Radio-Craft magazine. I post this
schematic and functional description of the
Arvin Model 35, 8-Tube Car-Radio Receiver manufacturers' publications for the
benefit of hobbyists and archivists who might be searching for such information
either in a effort to restore a radio to working condition, or to collect archival
information. A WWW search for an Arvin Model 35 Car Radio did not turn up any
results, but I did see the unknown model shown here on an expired eBay auction.
It has a speaker front that looks like the Model 35. Installing and servicing
the earlier heavy, bulky car radios was the source of many electronic-themed comics
and articles. Some of the very earliest two-way radio sets (of which this is not)
had massive transformers, needed to generate power for the transmitter...
"The
Double Asteroid Redirection
Test (DART) mission is directed by NASA to the Johns Hopkins Applied Physics
Laboratory with support from several NASA centers: the Jet Propulsion Laboratory,
Goddard Space Flight Center, Johnson Space Center, Glenn Research Center, and Langley
Research Center. DART is a planetary defense-driven test of technologies for preventing
an impact of Earth by a hazardous asteroid. DART will be the first demonstration
of the kinetic impactor technique to change the motion of an asteroid in space.
The DART mission is led by APL and managed under NASA's Solar System Exploration
Program at Marshall Space Flight Center for NASA’s Planetary Defense Coordination
Office and the Science Mission Directorate's Planetary Science Division..."
Most regular RF Cafe visitors will probably
not be too interested in this 1960 Popular Electronics magazine article,
but there are a lot of people who build and/or repair vintage radio gear and search
the Internet for helpful information. Having built a couple
crystal radio sets as a kid, I've always been amazed at how a few picowatts
of RF energy can be received, processed, and heard through an ear plug without the
need for external power from a battery. Speaking of crystal radios, I remember one
time while working as an electrician in Annapolis, Maryland, (prior to entering
electronics) I had a telephone handset for use in communicating with other electricians
in a building I was wiring, and it picked up the local AM radio station. A pair
of the old style handsets with carbon microphones would, with the help of a single
'D' cell in series, function as a very acceptable intercom system using two standard
electrical wires between them...
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 object has been built to fit proportionally on the provided
A-, B- and C-size drawing page templates (or can use your own). Stencils 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...
KR Electronics designs and manufactures
high quality filters for both the commercial and military markets. KR Electronics'
line of filters
includes lowpass, highpass, bandpass, bandstop and individually synthesized filters
for special applications - both commercial and military. State of the art computer
synthesis, analysis and test methods are used to meet the most challenging specifications.
All common connector types and package form factors are available. Please visit
their website today to see how they might be of assistance. Products are designed
and manufactured in the USA.
Sunday the 28th
Due respect is paid throughout this technically
themed crossword puzzle to the
Greek letter "Xi," which has been dissed by the World Health Organization by
omitting it from the succession of designations for new COVID-19 variants (look
for an asterisk after the clue). Xi has been restored to its rightful place as the
14th letter in the Greek alphabet. Only clues and words are directly to RF, microwave,
and mm-wave engineering, optics, mathematics, chemistry, physics, and other science
subjects. As always, this crossword contains no names of politicians, mountain ranges,
exotic foods or plants, movie stars...
This gives a whole new meaning to "Political
Science." Vaccinated people have been generating and shedding variants of COVID-19.
WHO designates each new variant with progressive letters in the Greek alphabet,
beginning with Alpha. Until a few days ago they were up to the Nu variant. Next
came Omicron. "What
happened to Xi?" you might reasonably ask. It so happens that Xi (Jinping) is
the name of China's dictator, so "the Science" we are admonished to listen
to decided to omit it. Now we need the Ministry of Truth to replace all former references
to Xi (Ξ, ξ) with some other symbol. Let me be the first to suggest a spiked
virus icon . Damping ratio henceforth
is written as = 2.5
rather than the traditional ξ=2.5. Similarly there is the
baryon (rather than the Xi baryon),
the Riemann function, potential difference is
volts, the Scientific Research Honor Society
is now Sigma . You get the idea...
Since 1996, ISOTEC has designed, developed
and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components
and filters for wireless service providers including non-magnetic connectors for
quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM
RF connectors components such as power dividers and directional couplers. Off-the-shelf
and customized products up to 40 GHz and our low-PIM products can meet -160 dBc
with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and
high-performance. Designs that are cost effective practical and repeatable.
Friday the 26th
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,"...
Shortly after
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
Semiconductor co-founder
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
Shockley
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
people..."
"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
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.
Thursday the 25th
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...
"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
30 years of experience designing & manufacturing RF & microwave passive
components. Their high power, broadband
couplers, combiners, resistors, baluns, terminations
and attenuators are fabricated using the latest materials and design tools available,
resulting in unrivaled product performance. Applications in military, medical, industrial
and commercial markets are serviced around the world. Please take a couple minutes
to visit their website and see how IPP can help you today.
Wednesday the 24th
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 virtues and evils of the plethora types
of
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...
Also
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)...
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...
Since 2003, Bittele Electronics has consistently
provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly
services. It specializes in board level turnkey
PCB assembly
for design engineers needing low volume or prototype multi-layer printed circuit
boards. Free Passive Components: Bittele
Electronics is taking one further step in its commitment of offering the best service
to clients of its PCB assembly business. Bittele is now offering common passive
components to its clients FREE of Charge.
Tuesday the 23rd
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
ship's 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
complimentary...
"The first day of Global MilSatCom 2021 will
primarily focus on the UK Ministry of Defence's (MoD) SATCOM needs and capabilities,
with particular emphasis on their
SKYNET Enduring Capability ( SKEC ) program. SKYNET is a family of military
communications satellites, currently operated by Airbus Defence and Space for the
UK Ministry of Defence (MoD), that provides strategic communication services to
the UK Armed Forces and allies. SKYNET 5 is the most recent generation of this family.
The SKYNET Enduring Capability (SKEC) programme will deliver the next era of satellite
communications (SATCOM) to the MoD using new space assets and a way to monitor and
control them. These assets will also be supported..."
Alliance Test Equipment sells
used / refurbished
test equipment and offers short- and long-term rentals. They also offer repair,
maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP,
Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization
with ability to source hard to find equipment through our network of suppliers.
Alliance Test will purchase your excess test equipment in large or small lots. Blog
posts offer advice on application and use of a wide range of test equipment. Please
visit Allied Test Equipment today to see how they can help your project.
The
November issue of Microwave Journal magazine printed an interview with
Marki Microwave's
Chris Marki,
engineer son of founder Ferenc Marki. Asked about the "100% Made in America" claim
of the company, Chris dismissed "any ideological reason" and said it was solely
due to being able to "manage and build the best hardware in the world." It was a
bit disappointing to see him evidently fear repercussions of claiming a patriotic
allegiance to the country in which his company's success stemmed. I used my first
Marki mixer (actually dealt with Marki's founder then) in an airborne ECM receiver
back in the mid 1990s and it had extremely good performance. After that I confidently
used other Marki products in high performance application thereafter. Chris mentioned
in the article that Marki Microwave has job openings now for qualified people. If
you want to work for a highly respected company, surf on over to the
Marki Microwave Careers
page now to see more than a dozen positions...
You have to be careful when working this
crossword puzzle from the August 1960 edition of Popular Electronics
magazine because in one instance the name of a certain federal agency has changed
since then, and in another instance the element cited as being "commonly used" no
longer is. It will add to the challenge, which, honestly, is not all that great.
I did not have the magazine page with the solution available when posting this so
I had to work the puzzle myself to create a solution. If you are an ardent cruciverbalist
as am I, you might want to try some of the hundreds of technically-themed crossword
puzzles I have created which have only words and clues related to science, engineering,
mathematics, etc...
Wien bridge oscillators had been around for
a few years prior to this article in the January 1941 issue of QST magazine,
but evidently they had not been applied widely to amateur radio applications. In
fact, Hewlett-Packard's very first product, the Model 200A audio oscillator, employed
a Wien bridge oscillator as its frequency determining circuit. U.S. patent 2268872
provides a detailed description of its operation as well as the basic schematic.
It was considered breakthrough design because its amplitude and frequency stability
rivaled that of the beat frequency oscillators of the day - at a small fraction
of the cost, size, and weight. The Model 200A quickly became a staple instrument
on the benches of designers and launched HP into the Keysight Technologies it is
today...
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!
Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products
such as RF signal generators, RF synthesizers, RF power detectors, mixers, up /
downconverters. Since the conception of WFT, we have introduced products that have
been purchased by a wide range of customers, from hobbyists to education facilities
to government agencies. Worldwide customers include Europe, Australia, and Asia.
Please contact Windfreak today to learn how they might help you with your current
project.
Monday the 22nd
John T. Frye was an electronics service
technician long before he began writing techno-dramas like "Mac's Radio Service
Shop" and "Carl & Jerry." His expertise and real-world experience evidenced
itself in the wide variety of situations and subjects covered in the stories. If
you have never read any of them, I whole-heartedly suggest that you sample a few
(or listen to one of my podcast readings of them). In this article from a 1949 issue
of Radio-Electronics magazine, Mr. Frye discusses what was evidently
a reluctance on the part of service men to acquire and/or use
printed service data when troubleshooting and/or aligning radios, televisions,
tape recorders, etc. The attitude of some elitists was that if you needed to consult
documentation that it was evidence of your ineptness; you were not a worthy electronics
technician. More than one episode of "Mac's Radio Service Shop" had owner Mac McGregor
admonishing young Barney about wasting time during troubleshooting by not consulting
the service data sheets he stocks in the shop. Even if a shop owner could not afford
the elite service literature from SAMS Photofacts...
"A University of Wollongong-led team across
three FLEET nodes has combined two traditional semiconductor doping methods to achieve
new efficiencies in the topological insulator bismuth-selenide (Bi2Se3). Two doping
elements were used: samarium (Sm) and iron (Fe). The resulting bismuth-selenide
crystals show clear ferromagnetic ordering, a large bulk band gap, high electronic
mobility, and the opening of a gap of surface state making this system a good candidate
to achieve QAHE at the higher temperatures necessary for viable, sustainable future
low-energy electronics. 'The
combination of electronic and magnetic properties in topological systems is
the keystone of novel topological devices, and one of the core projects in FLEET..."
Before there were CFL light bulbs with complicated
electronic circuits for generating the requisite high voltages without a transformer,
there were just the familiar straight (and sometimes circular)
fluorescent bulbs that use a simple ballast arrangement and a built-in switch
in the bulb base. As with compact fluorescent (CFL) lights, very few people understood
how they worked. Most knew that the 8-foot-long T-12 bulbs (the large diameter ones
used in commercial buildings) made a really cool implosion sound when they broke
- usually intentionally (by people like me) since the glass tubes are amazingly
tough. I remember many moons ago, between high school and the time I enlisted in
the USAF, while I was an apprentice electrician working on a renovation job at a
public school...
"CQD CQD HERE MKC SHIPWRECKED!"
Jack
Binns, who wrote the forewords for Allen Chapman's Radio Boys books, was supremely
qualified to comment on the subject of the fledgling and burgeoning wireless technology.
Mr. Binns was the radio operator aboard the "RMS Republic," a luxury liner
of the White Star fleet, when on January 23, 1909, it was rammed by the Italian
ship "Florida." Jack Binns is credited with orchestrating via wireless communications
what was at the time the world's largest (and first?) rescue at sea. It was likely
the motivation for The Radio Boys with the Iceberg Patrol (which I own and have
read). BTW, Mr. Binns was later offered and declined an opportunity to be the
radio operator on the RMS Titanic...
A few days ago I posted an old ad for Radio
Shack and mentioned the tube testers that used to be in the stores for customers
to use free of charge. Of course they also had a nice stock of replacement tubes
for you to buy if needed. This advertisement for a typical
vacuum tube tester by Century Electronics appeared in the December 1958 edition
of Popular Electronics magazine. According to the U.S. Bureau of Labor
Statistics' inflation calculator, that $134.50 price in 1958 (the year I was born,
BTW) would be equivalent to $1,287.24 in 2021 money - not too bad really if it were
still made in the USA as it was then...
SF Circuits' specialty is in the complex,
advanced technology of PCB fabrication and assembly, producing high quality multi-layered
PCBs from elaborate layouts. With them, you receive unparalleled technical expertise
at competitive prices as well as the most progressive solutions available. Their
customers request PCB production that is outside the capabilities of normal circuit
board providers. Please take a moment to visit San Francisco Circuits today. "Printed
Circuit Fabrication & Assembly with No Limit on Technology or Quantity."
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.
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.
Homepage Archive Pages
2025:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2024:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2023:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2022:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2021:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2020:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2019:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2018:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2017:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2016:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2015:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2014:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2013:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2012:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 (no archives before 2012)
- Christmas-themed
items
|