See Page 1 |
2 |
3 |
4 |
5 | of the August 2020 homepage archives.
Friday 14
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 are pretty
clever, but are somewhat dated for today's readers. To wit, the name Memamadun Ptolemy,
which for the uninitiated is an allusion to the movie "Blues in the Night," where
the actual words are "My momma done 'tol me..." (get it?). Another worthy mention
is, "Tube V or not Tube V, that is the question," an obvious play on Shakespeare's
"To be or not to be, that is the question" line by Prince Hamlet. If you recognize
those, you'll find other familiar takeoffs as well...
"The life-givers of
integrated circuits and quantum devices in silicon are small structures made
from patches of foreign atoms called dopants. The dopant structures provide charge
carriers that flow through the components of the circuit, giving the components
their ability to function. These days the dopant structures are only a few atoms
across and so need to be made in precise locations within a circuit and have very
well-defined electrical properties. At present manufacturers find it hard to tell
in a non-destructive way whether they have made their devices according to these
strict requirements. A new imaging paradigm promises to change all that. The imaging
mode called broadband electric force microscopy..."
When I think back at the
engineering labs
from my days in school, I wonder how much things have really changed from then until
now. It is hard to believe that freshman and sophomore labs are not still consumed
with radial lead resistors, inductors, and capacitors, solderless breadboards, and
a variety of light bulbs, motors, transformers, relays, and rheostats. By the time
you move into the junior year, labs have gotten a bit more intense with microprocessor
controls (mine used an 8088 CPU with machine language programming for the serial
port), some high voltage apparati[sic], digital logic circuits, and a chance to
lay out/fabricate/populate a PCB. On-hand test equipment consists of 2nd or 3rd
generation oscilloscopes, signal generators, and power supplies. I did a search
for photos of labs from back in the early to mid 1900s to see if much had changed
from then until the time I was in college...
On July 28, 2020, Apple was granted patent
number US10727570 entitled "Electronic
devices having antennas that radiate through a display." Abstract: "An electronic
device may be provided with a display and a phased array antenna that transmits
radio-frequency signals at frequencies greater than 10 GHz. The display may
include a conductive layer that is used to form pixel circuitry and/or touch sensor
electrodes. A filter may be formed from conductive structures within the conductive
layer. The conductive structures may include an array of conductive patches separated
by slots or may include conductive paths that define an array of slots. The filter
may include an additional array of conductive patches stacked under the array of
conductive patches to allow the slots to be narrower than would be resolvable to
the unaided human eye. The periodicity of the conductive structures and the slots
in the filter may be selected to tune...
RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave component
supplier. RF coaxial connectors & adapters, coaxial cable & cable assemblies,
surge protectors, attenuators. Items added daily. Free shipping on orders over $25.
We're leading the way again!
Thursday 13
Heathkit's claim to fame was that it was
able to offer user-assembled kits of high quality electronic products at a price
lower than what equivalent factory assembled equivalents would cost. While that
is probably generally the case, it is difficult to gauge what the relative quality
really is. Some of the kits were easy to assemble for even people with little experience,
but a good portion of them required familiarity with soldering and how electronics
were put together. The instructions provided were very thorough, complete with photos
and drawings of how each step should look. In fact, according to a 1972 installment
of Mac's Service Shop entitled "Philosophy of a Kit Manufacturer," every Heathkit
kit instruction booklet goes through a rigorous cycle of writing, testing, and rewriting
before being released for production...
Axiom Test Equipment, an electronic test
equipment rental and sales company has published a new blog post entitled "Practical
Solutions for Measuring Phase Noise" that examines phase noise, what it is,
why too much noise and frequency instability can be a problem in testing, and how
to find the right method and equipment for measuring it. Phase noise can often be
measured directly using different measurement approaches such as residual and cross-correlation
techniques, which are explored more in-depth in the blog. Most importantly, the
blog explains what specifications to look for in a spectrum or signal analyzer to
ensure the best fit for the job. A few equipment examples are given as guides...
Universum, a self-proclaimed "global employer
branding leader" that conducts research studies on career expectations,' surveyed
52,000 engineering students between October 2019 and April 2020 on their preferred
places of employment. They were asked who is your preferred employer upon graduation.
Design News created a slideshow of the results showing their
top 50 dream employers. Numbero uno is Tesla, a U.S. e-car maker, whose stock
just approved a
5:1 split after skyrocketing in value after its related (by ownership) sky rocket
(SpaceX - the #2 choice) business recently
succeeded in launching and returning two American astronauts to the ISS. #3 was
Lockheed Martin. Google only rated #4, Apple #7, Microsoft #8, . Lego - the plastic
block people, came in at #31. The USAF was #39. General Dynamics completed the list
at #50. If the list had gone to #51, RF Cafe would probably have been there.
"Scientists said they had discovered a way
to
detect space debris even in daylight hours, potentially helping satellites to
avoid the ever-growing cloud of junk orbiting the planet. Defunct rockets, satellites
and spacecraft parts continue to orbit Earth after they are discarded. The estimated
500,000 objects circling the globe range in size from a single screw to an entire
rocket fuel tank. Travelling at thousands of miles an hour, they pose a huge and
rising collision risk to satellites. Using lasers, it is possible to detect the
debris from the ground..."
One very satisfying aspect of 'rolling your
own'
audio frequency coils (aka chokes, aka inductors), is how well the simple inductance
equations match measured end results. Unless you really manage to mangle the job,
if you use the right equation and are reasonably careful to observe wire size, spacing
(including insulation), and core diameter, you will be amazed at how close practice
matches theory. Although strictly speaking audio frequencies run from a few Hertz
up to maybe 15 kHz for people with really good hearing. My experience is that
similar success can be had even into the low MHz realm with just a little tuning
required. It's not until you get into the realm of self-resonance that everything
starts falling apart with basic equations...
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. The P/N AE1200-1400DB5450
passes DC-1200 MHz and 1400-3000 MHz with a crossover insertion loss of
5 dB at 1300 MHz crossover frequency at 1300 MHz and in band insertion
loss of less than 1 dB. The AE2310B11640 passes the LTE band of 2305-2315 MHz
with an in-band insertion loss of less than 1 dB. The 2305-2315 MHz bandpass
filter exhibit a very sharp transition to the rejection band with a power handling
of 20 W...
Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave filters,
diplexers, and sub-assemblies. They offer the generally known tubular, LC, cavity,
and waveguide designs, as well as state of the art high performance suspended substrate
models. Through a continuous process of research and development, they have established
a full line of filters of filters of all types - lowpass, highpass, bandpass, bandstop,
diplexer, and more. Established in 1979. Please contact Reactel today to see how
they might help your project.
Wednesday 12
This "Electronic
Crossword" appeared in the September 1958 issue of Radio & TV News magazine.
Its creator, John Gill, designed specialty theme crossword puzzles for many other
editions of Radio & TV News and Electronics World (see the big list at the bottom
of the page). He considered this crossword to be a "fooler" because he claims
to include many "unusual definitions and a number of obscure words which you will
have to work around if your vocabulary of 'exotic words' is rusty." It really doesn't
seem so difficult to me, and anyone used to working my custom RF Cafe Crosswords
will have no problem with it.
To meet the challenging requirements of cellular
LTE and 5G NR infrastructure applications, Skyworks has released the
SKY67183-396LF and SKY67189-396LF low noise amplifiers (LNAs). These LNAs feature
ultra low-noise figure, exceptional linearity, and operate over a wide range of
frequencies. To reduce PCB board space, these devices are housed in an ultra-compact
2 x 2 mm plastic surface mount package. The SKY67183-396LF and SKY67189-396LF are
ideal for 2G/3G/4G/5G TDD and FDD infrastructure applications, including small cell,
massive MIMO, and macro base stations...
"After completing a countdown dress rehearsal,
Astra is gearing up for its first orbital launch attempt this week from Kodiak Island,
Alaska, but company officials said it will likely take multiple test flights before
the new
small satellite launcher successfully reaches orbit. Astra's small satellite
delivery vehicle was set for liftoff from the Pacific Spaceport Complex in Alaska
during a two-hour window opening at 10 p.m. EDT Sunday, or 6 p.m. local time in
Alaska. In social media updates, Astra said it fueled the small satellite launcher
with liquid propellants Sunday. But officials said out-of-limits upper level winds
and a boat in restricted waters offshore of the launch site..."
When someone with the first name of "True"
writes an article about transmission line feeds for short-wave antennas, you should
probably take note. This very topic has been covered in detail many times since
the use of impedance-matched transmission lines have been in use (more than a century),
but since there are always people new to the concept, it is good to keep introducing
the topic on a regular basis."Transmission-Line
Feed for Short-Wave Antennas" appeared in a 1932 issue of QST magazine.
Even in this era of prefabricated everything, it still often comes down to winding
coils and adjusting cable lengths to get optimal impedance matches between transceivers
and antennas.
I have
extolled the virtues of Aerospace & Defense Technology magazine many
times for its variety of extremely interesting articles on a wide range of topics.
The August issue has a story on the
element Vanadium (atomic number
23) and the critical role it
plays as an alloy component of metals. At concentrations of less then 0.1%, vanadium
can nearly double the strength of steel and aluminum, as well as increasing resistance
to corrosion. It is also used as a catalyst (sometimes a substitution for nickel
and platinum), in electronics components, and in ceramics. Use of vanadium is considered
"green" because most of it is obtained from byproducts of other industrial processes
like ash from coal burning. Vanadium is the earth's 22nd most abundant element and
is found everywhere, but as you might suspect China provides 61% of the supply while
the U.S. does a mere 3% (Russia makes 14%). Fortunately, part of the Dept. of Interior's
2018 charter was to include vanadium on its list of critical commodities and must
act to significantly increase domestic production rather than be dependent on foreign
sources. It's long past time.
Manufacturing
of all our products continues to operate at full capacity as part of the "Essential
Business" community. Professional high frequency
TSA89 series of RF test cables with performance to 40 GHz. Precision connector
choices include; SMA, Type-N, 3.5mm, 2.92mm, & 2.4mm. Key features: High-frequency
point to point cable, light weight rugged double-shielded, flexible cable, low loss <0.68 dB/ft
@ 40 GHz, low VSWR < 1.35:1 (Typical < 1.25:1), RF leakage >-100 dB
to 18 GHz, temperature rated from -55ºC to 125ºC. 100% factory VSWR and insertion
loss tested. Cables are in stock and available immediately from Digi-Key. Made in
the USA.
Electro-Photonics is a global supplier of
RF & Microwave components.
Their products include SMT hybrid and directional couplers, wire bondable passive
components, mounting tabs, filters, transmission lines, and very useful test boards
for evaluating components (spiral inductors, single-layer capacitors). The Electro-Photonics
team can support your small R&D design requirements with RF & Microwave
test fixtures and save you valuable design and characterization time. Please take
a moment to visit Electro-Photonics' website and see how your project might benefit.
Tuesday 11
The word prefix "para" can mean "above and
beyond" or "resembling" or "abnormal or incorrect." Ward Products probably preferred
first two be inferred by potential customers when naming their
PARA-CON television antenna, although it actually is a shortening of "parabolic."
The "con" part is a shortening of "conical." After reading the text of this full-page
advertisement from a 1951 issue of Radio & Television News magazine, I'm inclined
to assign the third prefix meaning of "para" to it. Then, add in the "con" part
where "con" can take on either the noun form meaning of "disadvantage" or the verb
form definition of "to trick or defraud," and you get what this antenna truly represented
in terms of achieving superior performance. At best the PARA-CON exhibited the characteristics
of a phased pseudo-[bi]conical antenna. The allusion to a parabolic antenna...
"Sensing devices have a range of industrial
uses - from carrying out ground surveys to monitoring volcanoes - and scientists
are developing ways to improve their sensitivity with quantum technologies that
are based on cold atoms. Machines using quantum technology are, however, bulky and
difficult to transport, making current designs unsuitable for most industrial uses.
According to Birmingham University, the researchers have used a new approach that
will enable
quantum sensors to shrink to a fraction of their current size. The research
was conducted by an international team led by Birmingham University and SUSTech
in China in collaboration with Paderborn University in Germany. Their results are
published in Science Advances..."
Not everyone who visits websites like RF
Cafe is a seasoned electronics veteran. While I and most likely you, too, can do
series and parallel circuit analysis (and series/parallel for that matter, possibly
using Fourier or La Place transforms for reactive AC circuits) in our sleep,
many are recently getting into the wonderful world of electronics who are just coming
of age or have suddenly at a later point in life developed a passion for the craft.
Accordingly, this article from Radio News magazine provides yet another
tutorial on the fundamentals of series and parallel circuit analysis. Only resistors
and basic Ohms law are covered...
Withwave's Precision
1.0 mm to 1.0 mm Adapter Series are designed based on precision microwave
interconnection technologies. Configurations include 1.0 mm (F) to 1.0 mm (F),
1.0 mm (M) to 1.0 mm (F), and 1.0 mm (M) to 1.0 mm (M).
These Adapters are manufactured to precise microwave specifications and constructed
with male and female gender on both side. The precision microwave connector interfaces
ensure an excellent microwave performance up to 110 GHz. Features: Frequency
range = DC to 110 GHz, VSWR (max) = 1.30:1, Body = stainless steel (passivated)...
Aegis Power Systems is a leading supplier
of AC-DC and DC-DC power supplies
for custom and special applications. Aegis has been designing and building highly
reliable custom power supplies since 1995. They offer a complete line of switch
mode power supplies and power converters for a variety of markets including defense,
industrial, aircraft, VME, and telecom. Supports military, aircraft, EV, telecom,
and embedded computing applications. Design and manufacture of custom power supply
solutions to meet each customer's exacting specifications. Please visit Aegis Power
Systems today.
Monday 10
Here are a couple more
tech-themed comics from a vintage electronics magazine (Popular Electronics).
The one from page 101 reminds me again about how different the world of retail sales
is today compared to just two short decades ago. Prior to the advent of online marketing
and sales, you either walked into a brick and mortar (a term rarely heard before
the Internet era) type store and walked out with your purchased product, or you
thumbed through a catalog and placed an order either by mail or telephone. Most
people opted to pay for a postage stamp rather than pay the long distance phone
charge (a term rarely heard today). Free overnight or 2-day shipping from many e-stores
makes online shopping nearly as instantaneous as walking into a store. People under
20 years old have never known much different, but some old-timers still find the
paradigm change strange. The way things are going...
Exodus Advanced Communications
Intros X-Band High Power Pulse Amplifier
Exodus Advanced Communications' model
Exodus AMP5055P-SSC Pulse Amp (9.6-9.9 GHz, 150 W pulse) is IP67 rated
and fully qualified for outdoor applications. Designed for Pulse/Radars in the harshest
of environmental conditions up to a 20% duty cycle. The unit provides outstanding
Pulse fidelity, excellent band flatness, all in a compact lightweight package with
the highest reliability. Other frequency ranges & power levels available. Features:
Outdoor waterproof packaged high power SSPA, class AB Pulse, GaN design, designed
for high power X-band pulse applications, built-in control, monitoring, and protection
circuits, high reliability and ruggedness...
Since this is a presidential election year,
I figured it would be a good time to post a tongue-in-cheek- story that appeared
in the November 1952 issue of QST magazine about a fictional American president
J. Willoughby Winkelspoof. The ARRL always has been and still is apolitical,
so don't take seriously anything you read here. If you are an astute follower of
politics, you might pick up on the nuances woven into the story, and might even
marvel on how much the political landscape has changed in the half century since
Pres. Winkelspoof graced the Oval Office. Incidentally, the 1952 presidential election
was between Dwight D. Eisenhower and Adlai Stevenson. You might wonder how many
U.S. presidents were/are Amateur Radio operators. Answer...
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.
Frequent
visitor and contributor Joe B. sent me a link to a page entitled, "40 Hilarious
Ads For Technology From The Past That Look Insanely Expensive Now." It fits
in well with the theme of RF Cafe so you might enjoy being reminded of (if you're
old like me) or seeing for the first time (if you're not old like me) what people
were paying for technology which was bleeding edge then and is toy-quality now.
No kidding. Pick any microprocessor-driven toy from a shelf at Walmart and it will
have nearly as much memory and processing power. One example is a 10 MByte
hard drive costing $3,398 in 1981, which is the equivalent of $10,069 ($1k/MByte)
in 2020 money per the BLS
Inflation Calculator. These kinds of themes can be found all over the Internet,
and as usual, the same set of examples are repeated on those pages. Do an image
search on "10
mbyte hard drive ad" and you'll see what I mean.
Teledyne Aerospace & Defense Electronics
UK (TADE UK) announced the latest business unit addition to its brand portfolio,
Teledyne
Energetics UK, headquartered in Lincoln, England. Visit the home page of the
company's new website here. The new website gives an overview of the Energetics
UK systems, subsystems, and component offerings, which are ITAR-free and designed
and manufactured exclusively in the UK. The website promotes the company's extensive
heritage in all major deployment theatres including aerospace, land, surface maritime,
subsea ASW and LEO launch. Teledyne Energetics UK designs and develops solutions
for the safety, arming, and initiation technology sector, in particular military
energetic devices...
NorthEast RF's comprehensive
antenna testing
services include linear | circular polarized antenna measurements and OTA cellular
device pre-compliance. Up to 18" diameter and <10 kg weight. Antennas can be
rapidly evaluated and optimized using our fast near field spherical system. Test
results supplied in data file with pattern viewer software. A picture of the test
configuration is included to help aligned axis. Our selection of human head and
hand phantoms are ideal for verification of body worn devices. Turnaround time is
usually 3-days.
Sunday 9
August 9th's custom
Amateur
Radio crossword puzzle contains many words particular to Amateur Radio (labeled
with an asterisk *). 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 Lamarr or the Bikini Atoll, respectively. Avid cruciverbalists
amongst us...
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.
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