Today in Science History -
 This 1954 issue of Radio-Electronics
magazine reported on the death of electronics communications pioneer
Major Edwin H. Armstrong. Most famously known for his wideband FM (frequency
modulation) scheme, Maj. Armstrong also developed the superheterodyne circuit,
the superregenerative circuit, and was an independent inventor of regeneration.
As with many prodigious, prolific inventors throughout the ages, he spent much time
and fortune battling legal claims against himself and against others. Interestingly,
the news item does not mention that Major Armstrong, who was famous for his daring
antics at the tops of extremely high antennas, died after jumping out of his New
York City apartment window. It was ruled a suicide based on a note he left for his
wife. Also included is a bit about a judge allowing radar data from police as evidence
in a speeding charge, and a statistic showing 47,000 people injured themselves in
the past year during TV antenna installations...
 Augustin-Jean Fresnel, the same guy who
developed the "Fresnel zone"
equation for determining the effective RF propagation region between a transmitter
and a receiver, also invented this prismatic lens for concentrating the source of
illumination of a lighthouse in the direction most useful to seafaring vessels (aka
ships and boats). This IEEE Spectrum article entitled "Before Ships Used GPS, There
was the Fresnel Lens" dives into the history of the world-changing device. It
begins: "Ships today use satellite-based radio navigation, GPS, and other tools
to prevent accidents. But back at the beginning of the 19th century, lighthouses
guided ships away from rocky shores using an oil lamp placed between a concave mirror
and a glass lens to produce a beam of light. The mirrors were not very effective,
though, and the lenses were murky. The light was difficult to see from a distance
on a clear night, let alone in heavy fog or a storm..." Here is a nice
video explaining the Fresnel
lens and its nautical import.
 Here is
Zenith Models 5D011-5D027 schematic and parts list as featured in a 1947 edition
of Radio News magazine. Unlike with most of the Radio Service Data Sheets,
this came from group of three which also included the Bendix Models 636A, C, D and
the Coronet Model C-2, al three of which are tabletop models. As mentioned many
times in the past, I post these online for the benefit of hobbyists looking for
information to assist in repairing or restoring vintage communication equipment...
 Planar Monolithic Industries (PMI), a leading
supplier of custom, high-reliability MIC/MMIC components and subsystems for applications
in space, military, communications, commercial and consumer electronics systems
for more than three decades, announces a dba (doing business as) name
change to Quantic PMI. They also have introduced a new 6−Channel Switch
Filter Bank that operates over the frequency range of 55 to 18.5 GHz, with
a typical VSWR of 1.7:1, a maximum switching speed of 200 ns, and a typical
insertion loss of 4.0 dB. Contact PMI today for more information...
 These two
electronics-themed comics appeared in a 1952 edition of Radio &
Television News magazine. In the early days of television, it was common in
comedy skits and in cartoons to have someone on a television show interact, to the
viewer's great shock, directly with the viewer or to reach out of the set and do
something, as in the first comic here. The Three Stooges show did that in a couple
shows. One in particular I remember was when they were doing plumbing in a house
and had water coming out of light sockets and telephones. The homeowners were watching
the TV with a film of Niagara Falls when suddenly water came gushing out of the
picture tube (begins at 13:20 in video)...
 This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers"
Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's"
design has been ripped off by other people and used on their products, so please
be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢ per
item - Cafe Press gets the rest of your purchase price. These would make excellent
gifts for husbands, wives, kids, significant others, and for handing out at company
events or as rewards for excellent service. It's a great way to help support RF
Cafe. Thanks...
 Berkeley Nucleonics Corporation (BNC) is
a leading manufacturer of precision electronic instrumentation for test, measurement,
and nuclear research. Founded in 1963, BNC initially developed custom pulse generators.
We became known for meeting the most stringent requirements for high precision and
stability, and for producing instruments of unsurpassed reliability and performance.
We continue to maintain a leadership position as a developer of custom pulse, signal,
light, and function generators. Our designs incorporate the latest innovations in
software and hardware engineering, surface mount production, and automated testing
procedures.
 Both my father and grandfather were
stamp collectors - philatelists is the technical word - who dabbled in a recreational
way with commemoratives from foreign countries. Nearly all were canceled (used)
stamps that today, as back in their day, have no real value other than to someone
interested in history. Of course none are the rare types. I now possess many of
those stamps in an album that was painstakingly hand-illustrated and assembled to
arrange each stamp according to its country and issue date. At one time I, too,
dabbled in the hobby, having collected many plate blocks and special issue U.S.
stamps in the 1970s and 1980s, along with purchasing a few designs of special purpose
such as those with aerospace and communications themes. Sad to say, most of those
stamps, even those in mint condition, are valued at the denomination printed on
the face - meaning inflation has reduced their worth to even less than when originally
purchased. If indeed "what's past is prologue...
 This story entitled "Universal
Access Akin to the Electrification of Rural America" is right from the standpoint
of making Internet available in nearly every region of the country. However, there's
one huge difference between the
Internet for All (IFA) scheme and the
Rural Electrification
Act (REA) of 1936. Whereas he REA made electric power available to users, the
end user paid for energy consumed. The IFA either gives away the data usage or provides
deep discounts, while those of us who pay full price for service and pay income
taxes foot the bill - while being demonized by the government and the (often) freeloaders.
Also, the REA did not provide the implements which would benefit from the electric
power (motors, radios, refrigerators), but the government will be handing out cellphones
and PCs to connect to the Internet. Whether through direct taxes or inflation due
to money printing, the rest of us pay dearly for it. The article begins: "Step by
step the $1T infrastructure package is becoming reality The next phase of the U.S.
"Internet for All" initiative has kicked off with governors and other eligible leaders
being invited to submit a letter of intent as a step towards unlocking $45B to give
every U.S. resident access to high-speed internet by 2028. Each state will then
get $5M..."
 My first thought when seeing the cover for
this December 1936 edition of Radio-Craft magazine was that it was an April
Fools gag, but it turns out the
"Hat" being worn by the radio receiver's designer is a loop antenna for AM reception.
In a way it is the opposite of a tinfoil hat in that this headgear invites electromagnetic
energy around the wearer's head rather than shielding it. Back in 1936, being seen
in public donning a contraption like this radio would have been akin to wearing
Google Glass (a failed concept) a few years ago - you'd be a superhero to fellow
nerds, and just be confirming your otherworldly nerd status to non-nerds. Note the
very nicely done drawings...
 RF Cafe's raison d'être is and always has
been to provide useful, quality content for engineers, technicians, engineering
managers, students, and hobbyists. Part of that mission is offering to post applicable
job openings. HR department employees
and/or managers of hiring companies are welcome to submit opportunities for posting
at no charge. 3rd party recruiters and temp agencies are not included so as to assure
a high quality of listings. Please read through the easy procedure to benefit from
RF Cafe's high quality visitors...
 ASC designs and manufactures hybrid, surface
mount flange, open carrier and connectorized amplifiers for low, medium and high
power applications using gallium nitride (GaN), gallium arsenide (GaAs) and silicon
(Si) transistor technologies. ASC's thick film designs operate in the frequency
range of 300 kHz to 6 GHz. ASC offers thin film designs that operate up
to 20 GHz.
 This custom made
Analog Engineering theme crossword puzzle for May 22nd is provided compliments
of RF Cafe. All RF Cafe crossword puzzles are custom made by me, Kirt
Blattenberger, and have only words and clues related to RF, microwave, and mm-wave
engineering, optics, mathematics, chemistry, physics, and other technical subjects.
As always, this crossword puzzle contains no names of politicians, mountain ranges,
exotic foods or plants, movie stars, or anything of the sort unless it/he/she is
related to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska
event in Siberia). The technically inclined cruciverbalists amongst us will appreciate
the effort. Enjoy!
 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...
 Exodus Advanced Communications is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Power amplifiers ranging
from 10 kHz to 51 GHz with various output power levels and noise figure
ranges, we fully support custom designs and manufacturing requirements for both
small and large volume levels. decades of combined experience in the RF field for
numerous applications including military jamming, communications, radar, EMI/EMC
and various commercial projects with all designing and manufacturing of our HPA,
MPA, and LNA products in-house.
 The proper care and feeding of
vinyl records was - and still is - a big topic amongst audiophiles. As with
so many things, phonographs and platters have experienced a resurgence in popularity
in the couple decades as the world gets nuttier and people crave for a simpler,
saner time - imagined or otherwise. I remember back in the barracks at Robins AFB,
GA, where there was always at least one guy who would have a very extensive (pronounced
"expensive") stereo setup complete with an equipment rack, reel-to-reel tape player,
dual cassette tape deck, super-sensitive AM/FM receiver with a huge tuning knob
on the front, a turntable with a precisely balanced and weighted tone arm (with
a stylus that cost two month's pay for an enlisted man), a multi-hundred watt power
amplifier that never had the opportunity to put out more than a small percentage
of its capability due to barracks noise rules, a patch cable panel for routing signals,
and monster speakers...
 The term "ovonic" - a fairly unfamiliar word
these days - appeared in the May edition of Radio-Electronics, in an article
entitled, "All About Ovonics," just a few months after this news item ran in the
January issue (which I posted last month).
Ovonics is a portmanteau of "Ovshinsky" (from Stanford R. Ovshinsky, the inventor)
and "electronics." Read the "All About Ovonics" article for a deeper dive into the
subject. The big deal, which turned out to be not a big enough deal, was the use
of amorphous (strangely spelled "amphorous") glassy compounds as semiconductors
rather than the standard crystalline silicon structures. Maybe someday an enterprising
genius inventor type will give a rebirth to the concept...
 "It was a great idea for its time - a network
of NASA communications satellites high in geostationary orbit, providing nearly
continuous radio contact between controllers on the ground and some of the agency's
highest-profile missions: the space shuttles, the International Space Station, the
Hubble Space Telescope, and dozens of others. The satellites were called TDRS -
short for Tracking and Data Relay Satellite - and the first was launched in 1983
on the maiden voyage of the space shuttle Challenger. Twelve more would follow,
quietly providing a backbone for NASA's orbital operations. But they've gotten old,
they're expensive, and in the 40 years since they began, they've been outpaced by
commercial satellite networks. So what comes next? That's the $278M question - but,
importantly, it's not a multibillion-dollar question..."
 How RF circuits work have long been referred
to as "black magic," even sometimes by people who fully understand the theory behind
the craft. To me, the ways in which a transmission line - be it coaxial cable, microstrip,
or waveguide - can be manipulated and controlled with various combinations of lengths
and terminations is what most qualifies as "magic." Sure, I know the equations and
understand (mostly) what's happening with incident and reflected waves, etc., and
how the impedance and admittance circles of a
Smith
chart graphically trace out what's happening, but you have to admit there's
something mystical about it all. Fortunately, Mr. John Marshall published this
"Antenna Matching with Line Segments" article in the September 1948 issue of
QST magazine...
 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. Three new filter models have been introduced
- a cavity bandpass filter with a bandwidth of 15 MHz ±2 MHz, an insertion
loss of 3.5 dB; a ceramic duplexer with a Band 1 frequency of 824 to 835 MHz
and a Band 2 frequency of 869 to 880 MHz; and an LC highpass filter with
a pass band of 402 to 1500 MHz with an insertion loss of less than 1.0 dB.
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...
 Unlike today when resources of all types
seem to be endlessly available, during World War II countries needed to collect
and recycle much in the way of metal, rubber, cloth, and other basic materials for
re-purposing into products used in fighting the enemy. Media coverage of bottle,
metal, and tire drives showed children pulling Radio Flyer wagons loaded to overflowing
with such items gathered from trash piles and soliciting neighborhood residents
for anything that could be spared. Raw materials were not the only type of items
needed, however. "Use it up, Wear it out, Make it do, or Do without" was the slogan.
Finished goods like electronic components - vacuum tubes, transmissions cable, transmitters
and receivers, tuning capacitors, d'Arsonval meter movements, and other parts -
were sorely needed by manufacturers both for building new equipment and for servicing
damaged gear. After the war was won, the
War Assets Administration made good on the government's promise to reward citizens
for performing their patriotic duty. This four-page spread in a 1947 edition of
Radio News is an example of the effort to make surplus components available...
 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!
 Withwave manufactures an extensive line of
metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
fully automated
4-port vector network analyzer (VNA) calibrator, between- and in-series connector
adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes &
probe positioner. Special test fixtures for calibration and multicoax cable assemblies.
Frequency ranges from DC through 110 GHz. Please contact Withwave today to
see how they can help your project succeed.
 The
G−Line
(aka G−String) RF transmission system is a rather amazing invention contrived through
out-of-the-box thinking by its inventor, Dr. George Goubau (from whence the
"G" in the name derives). He determined that a sort of waveguide could be made with
a single conductor surrounded by insulation with a specific dielectric constant
that would cause the dielectric-air interface to reflect the wave in a manner similar
to atmospheric channels that facilitate long distance communications. The G-Line
is designed to efficiently transmit UHF television signals (470 - 806 MHz),
and like a waveguide exhibits a lower cutoff frequency (~300 MHz), thus acting
like a highpass filter. G−Line has its weak points, like that it must not come near
to obstacles that will affect the dielectric-air interface or the line will radiate
like an antenna. Also, over time the insulation cracks and/or absorbs moisture and
changes the impedance parameters, thus affecting the transmission characteristics...
 "Researchers based in Russia report on molecular
beam epitaxy (MBE) of indium gallium arsenide (InGaAs)
quantum dots/wires (QDs/QWs) in aluminium gallium arsenide (AlGaAs) nanowires
(NWs) on silicon (Si) 'for the first time' [Rodion R. Reznik et al, Phys. Status
Solidi RRL, p2200056, 2022]. The research team at St. Petersburg State University,
Alferov University, Institute for Analytical Instrumentation RAS, Ioffe Physical
Technical Institute RAS, and National Research University Higher School of Economics,
have previously studied MBE synthesis of GaAs QDs inside AlGaAs nanowires on silicon.
The researchers comment that these hybrid nanostructures were effective sources
of single photons in a wavelength range of 750–800nm. Thus, they constitute 'promising
candidates for use in quantum cryptography and alkali metal..."
 Copper Mountain Technologies has a webinar
coming up in league with Eravant as part of our VNA 101 Bootcamp Webinar series
titled "Starter
mmWave Measurements." It begins on May 24, 2022, at 2 PM ET. This webinar will
demonstrate Eravant's VNA frequency extenders and their ability to perform full
two−port S−parameter measurements of millimeter−wave components. The example test
system will include Eravant's Proxi−FlangeTM waveguide adapters, as well as the
Wave−GlideTM positioning system. The VNA frequency extenders add full waveguide-band
frequency coverage to several industry-standard coaxial VNAs, including models available
from Copper Mountain Technologies. Proxi-Flange contactless waveguide flanges enable
fast and repeatable connections between VNA frequency extenders and the waveguide
components being tested. The Wave−Glide positioning system further streamlines component
testing by maintaining the alignment between VNA frequency extenders and the components
being tested while providing an easy and reliable method...
 While not many people are likely to build
this
R-C bridge circuit with vacuum tubes for use during design and troubleshooting,
this 1947 Radio News magazine article has a good basic description of operation
of any calibrated bridge circuit used to measure an unknown value. Interestingly,
a "magic eye" or "cat's eye" tube is used in lieu of a meter movement to give a
visual indication of an open, short, intermittence, poor power factor, and low "Q,"
as well as when the selected switch position correctly identifies the value of the
resistor or capacitor under test. Note that in that era μfd = μF and μμfd = pF...
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