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4 of the March 2019 homepage archives. Friday 22
 According to the somewhat limited unique information
available about the "nuvistor" vacuum tube amplifier, it was superior to many
glass-encapsulated vacuum tubes. Lower noise figure, smaller size, greater
ruggedness, intrinsically shielded, and relatively higher operating frequency
were the main marketing standpoint. RCA introduced the nuvistor in 1959, and
shortly thereafter GE, started making them, and then by 1964 Hitachi was
offering nuvistors. The manufacturing process, where the entire assembly was
performed in a vacuum chamber, made nuvistors more expensive than competitor
glass tubes. The nuvistor concept might have been big if transistors had not
been making such rapid progress in supplanting most vacuum tubes. In fact,
nuvistors (a portmanteau of "new" and "transistor") were supposed...
 "Part 1 of this series [by Kenneth Wyatt] described how digital
signals propagate through PC boards. In part 2, we look at specific board designs
to achieve
low EMI. The biggest issue I see in my clients' board designs
is poor layer stack-up. Reiterating the two fundamental rules from part 1 and
realizing digital signals and power (transients) are electromagnetic waves
moving in the dielectric layer, we see there are two very important principles
when it comes to PC board design: Every signal and power trace (or plane) on a
PC board should be considered a transmission line. Digital signal propagation in
transmission lines is really the movement of electromagnetic fields in the
space..."
 This
vector circuit matching quiz will hurt the brain a little more
than most of the ones that were printed in Popular Electronics. In order to
score well, it helps to visualize the circuits relative to where they would
appear on a Smith Chart. Capacitive impedances lie in the bottom half and have
negative phases (-s, -jω). Inductance lie in the upper half and have positive
phases (s, jω). The familiar 'ELI the ICE man' mnemonic helps, too. Be sure to
pay attention to the color of the vector arrow heads. Example: In a purely
inductive circuit like #4, voltage leads current by 90°. Since phase rotation is
CCW, you need to look for lettered phase diagram where the white arrowhead
(voltage) is 90° ahead of the black arrow head...
 "To keep up with Moore's Law - an observation
made in the 1960s that the number of transistors on an integrated circuit doubles
about every two years - researchers are finding ways to cram as many transistors
as possible onto microchips. The newest trend is 3D transistors that stand vertically,
like fins, and measure about 7 nanometers across - tens of thousands of times thinner
than a human hair. Tens of billions of these transistors can fit on a single microchip,
which is about the size of a fingernail. A modified chemical-etching technique,
called
thermal atomic level etching (thermal ALE), was used to enable
precision modification of semiconductor materials at the atomic level..."
 Custom MMIC is a
fabless RF and microwave MMIC
designer entrusted by government and defense industry OEMs. Custom and
off-the-shelf products include switches, phase shifters, attenuators, mixers and
multipliers, and low noise, low phase noise, and distributed amplifiers. From
next-generation long range military radar systems, to advanced aerospace and
space-qualified satellite communications, microwave signal chains are being
pushed to new limits - and no one understands this more than Custom MMIC. Please
contact Custom MMIC today to see how they can help your project...
Thursday 21
 Z-Comm announces a new RoHS compliant Fixed
Frequency Synthesizer model SFS0640A-LF in the UHF frequency. The
SFS0640A-LF is a single frequency synthesizer that operates at
640 MHz with an external 10 MHz reference and features a typical phase
noise of -100 dBc/Hz, -105 dBc/Hz, and -124 dBc/Hz at the 1 kHz,
10 kHz and 100 kHz offsets, respectively. The SFS0640A-LF is designed
to deliver a typical output power of 0 dBm with a VCO voltage supply of 5 Vdc
while drawing 25 mA (typical) and a phase locked loop voltage of 3 Vdc
while drawing 9 mA (typical). This Fixed Frequency Synthesizer...
 These NEETS training modules created by the
U.S. Navy appear to have originally come out in 1990s and has been modernized a
few times since then, so the information is fairly up to date. You will still find
a lot of descriptions of vacuum tubes, but that is because even in 1998 the military
still had a lot of legacy equipment that needed to be maintained. This particular
module provides the student with an introduction to and history of
semiconductor physics. The chapter runs a total of 62 pages so
there's a lot of content...
 "The aerospace giant Lockheed Martin is working
with Sequans Communications to develop new
LTE for satellite technologies. The two companies are enabling
LTE end user devices to connect directly to geostationary satellites in what they're
describing as a world-first achievement with wide application. 'Sequans has expertise
adapting LTE technology for special purposes such as this one,' said Scott Landis,
a director at Lockheed Martin, in a press release. 'Sequans engineers modified
their existing LTE chips to enable a new LTE-to-satellite communication
specification developed by Lockheed Martin. LTE to satellite represents an
important breakthrough in mobility and connectivity..."
 "Praetersonic" - now that's a word you don't
run up against very often. It is a combination of praeter* (beyond) and sonic (related
to sounds), or what more familiarly is called ultrasonic. If fact, praetersonics
was the early term given to
surface acoustic wave (SAW) piezoelectric devices. Amazingly,
even as far back as the early 1970s, SAW filters were being fabricated that
worked in the 40 MHz realm. This Popular Electronics article does a really nice
job of introducing the basics of SAW and BAW (bulk acoustic wave) technology at
the time it was coming into the mainstream. Lots of hurdles still needed to be
overcome, like high insertion loss, difficult to control impedances and internal
signal reflections, etc. As with many new technologies, pundits cast hopeful
prediction...
 ConductRF's close partnership with TE in
its development of its new
Nano-miniature RF Solutions for VITA67.3 has put us in a great
position to support your VPX RF cable assembly needs. We can support solutions
up to the top frequencies of the new connector system. ConductRF's PFT33 Series
of Micro Flexible Cable Assemblies has been designed directly with TE
Connectivity involvement and in partnership to maximize the capabilities of TE's
new Vita67.3 NanoRF VPX Modular connector system. ConductRF offers its soft FEP
jacketed ø0.047"cable to facilitate maximum flexibility and provides solutions
for jumper cables or assemblies to SMA, MCX...
Wednesday 20
 Transtector Systems, an Infinite Electronics
brand, today released a new, comprehensive line of NEMA-rated
weatherproof equipment enclosures that are engineered to
securely protect mission-critical electronics and are available with same day
shipping to meet crucial deadlines. The new TEF14-series includes 45 enclosure
configurations and 15 essential accessories available for immediate shipment.
The line features multiple configurations for global applications including
industrial automation, SCADA, oil and gas, mining, transportation, public works,
security and automation, and much more. Each enclosure provides vital protection
for key electronic...
 "Researchers from the Moscow Institute of
Physics and Technology teamed up with colleagues from the U.S. and Switzerland and
returned the state of a quantum computer a fraction of a second into the past. They
also calculated the probability that an electron in empty interstellar space will
spontaneously travel back into its recent past. The study is published in Scientific
Reports. 'This is one in a series of papers on the possibility of violating
the second law of thermodynamics. That law is closely related to the notion of the
arrow of time that posits the
one-way direction of time from the past to the future,' said the
study's lead author Gordey Lesovik..."
 How many of you
remember listening to Casey Kasem's
American
Top 40 show on the wireless (aka radio) on Saturday afternoons back in
the 1970s and 80s?
WPGC was my station of choice. The opening music and
tag
line by Kasem is forever etched on my mind. I fill my days listening to the
local Oldies station here in Erie (WMCE), so the familiar songs are still current to me. As with
most things these days, extensive archives of the original American Top 40
broadcasts are available online. It is interesting to listen in on announcements
of "new" songs making the Charts that are now 40 years old. If you like to wax
nostalgic, tune in to a few...
 "The undersea West African Cable System links
Africa with Europe. Huawei Marine Networks Company made upgrades. A new front has
opened in the battle between the U.S. and China over control of global networks
that deliver the internet. This one is
beneath the ocean. While the U.S. wages a high-profile
campaign to exclude China's Huawei Technologies Company from next-generation
mobile networks over fears of espionage, the company is embedding itself into
undersea cable networks that ferry nearly all of the world's internet data..."
Transient Specialists specializes in
EMC test equipment rentals
and carries a complete line of ESD guns, surge immunity test equipment, and EFT
generators. Rentals available for military (Mil-Std 461), automotive (ISO 7637),
and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited calibrations
and technical support on EMC testing equipment offered. Equipment consists of top
EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and EMC
Partner...
Tuesday 19
 If
television was "a chinch," in 1953 as this Radio-Electronic
article claims, the world would have had it long before then. Just like looking
up the work-out solutions to a physics problem in the back of a textbook, a lot
of things look simple and obvious once someone else has already done it. I guess
that's not really a fair criticism of this piece since author Aisberg's goal is
to assuage some of the doubts and misconceptions a lot of people had about the
relatively new technology. 1953 is the year that the NTSC formalized its color
TV standard, which, BTW, was careful to accommodate B&W transmissions on the
same channels - similar to how AM-FM stereo and stereo FM radio can coexist with
monaural (mono) broadcasts. Television, in case you are not aware, began as an
electromechanical system with picture frames and shutters, spinning discs, and
other Rube Goldberg contraptions...
 Rohde & Schwarz has produced a new webinar
titled "Automated RF Component Test for Design Engineers Without Programming,"
available for viewing at no cost. Martin Lim, National Applications Engineer at
R&S, is the presenter. "The complexity of RF designs is increasing and the
pressure to hit market windows is too. Enabling the automation of repetitive
tests like a power sweep over frequency can greatly help confirm if a new design
is ready or if further work needs to be done. Unfortunately, programming is
usually outside the normal responsibilities of most RF designers and include
time-consuming drawbacks like wading through long programmers manuals and
debugging code. This On Demand Webinar...
 The more things change, the more they remain
the same. People (including, admittedly, me) don't want to have to pay for any type
of media delivery, especially when it arrives via air waves or the Internet. Six
months before I was born, a reader of Radio-Electronics magazine wrote
to declare his outrage at the fledgling industry of
Pay Television. That a viewer would be expected to pay the
broadcaster for a show that was being, in his opinion, amply subsidized by
advertisers, was an outrageous concept, an unthinkable assault on all that is
holy. While his indignation was probably shared by the majority of the
television viewing public, evidently the maniacal scheme succeeded. In the 1950s
and even through part of the 1970s, television shows typically included about
10-12 minutes of commercials and other non-show segments for each hour of
broadcast. Season 1, Episode 1 of Star Trek, for example, ran for 50 minutes;
that was in 1966...
 "Gene Frantz may have been the visionary
for DSP back in the 1970s, but now he thinks we need to turn our attention back
to analog
to tackle the big challenges of artificial intelligence (AI). Previously a principal
technology fellow at Texas Instruments, Frantz is now a professor at Rice University.
He is also the co-founder and chief technology officer at at Octavo Systems, a fledgling
semiconductor-in-package (SiP) company based in Austin, Texas. Speaking during the
launch of Octavo's OSD32MP1 - the company's first SiP based on the newly announced
STMicroelectronics STM32MP1 microprocessor - Frantz told EE Times that he believes
SiP and analog processing will be the future. He said AI needs a better solution
and suggested that we should consider going back to analog signal processing..."
 Nova
Microwave is a leader in technically differentiated electronic and radio frequency
Ferrite Circulators and Isolators
that connect, protect and control critical commercial and military wireless
telecommunications systems. Our staff is dedicated to research and development
of standard and custom design quality Ferrite Circulators and Isolators from
380 MHz to 26.5 GHz. Please visit Nova Microwave today...
Monday 18
Software Defined Radio Handbook (Pentek)
14th Edition
 Pentek has published the 14th edition of their
popular "Software Defined Radio Handbook." The download is free, but you
need an account to access it on their website. Written by Pentek vice-president
and cofounder Roger Hosking, it is mostly an infomercial for their products, but
the first dozen pages contain good background information on topics such as sampling,
principles of SDR, and FPGAs. A readily accessible version is available
here
if you do not like creating new accounts...
 "A 3D printing technique from UC Berkeley
shapes objects all at once rather than layer by layer, allowing for more complex
and smooth objects. A new
light-based 3D-printing approach and machine can fabricate
complex objects in minutes that are smoother and more flexible than what's
currently possible. Dubbed the 'replicator' - a reference to the Star Trek
television program - and developed by researchers at UC Berkeley, the printer
uses a ray of light to transform liquids into objects all at once rather than
layer by layer, which is how typical 3D printers create objects. The replicator
was a device on the famous program that would materialize any object on
demand..."
 We hear and read a lot in the news about
the electronic surveillance carried out by governments - on both foreign
entities and civilians. If you think this is a phenomenon that has only existed
since the age of cellphones and the Internet, you might be interested in this article
that appeared in a 1945 issue of the ARRL's QST magazine. Long before
the entire textual content of the Encyclopedia Britannica could be carried on a
USB stick in your pocket - and access virtually all the information in the world
on your iPhone, engineers were developing recording media to facilitate the
capturing and later analysis of over-the-air and wired communications. They
wanted both encrypted and unencrypted conversations. The National Archives has a
huge store of magnetic tapes, vinyl discs...
 Ha! I've never heard the term "not-spot" before to describe a area with no coverage. "Start-up
UbiquitiLink reckons it's cracked the challenge of affordable satellite connectivity
to regular handsets through the use of nanosatellites. You can't use traditional
geostationary satellites to fill regular cellular coverage gaps because they're
too expensive and are positioned 35,000 km above the surface of the earth, which
is way further than cellular signals are designed to go and introduces excessive
lag to the signal. An obvious solution is to use satellites at a much lower orbit,
but until now that hasn't been economically viable. UbiquitiLink reckons it has
the answer to this conundrum and went to MWC last week to tell everyone all
about it..."
 PCB Directory is the largest
directory of Printed Circuit Board (PCB) Manufacturers, Assembly houses, and
Design Services on the Internet. We have listed the leading printed circuit
board manufacturers around the world and made them searchable by their
capabilities - Number of laminates used, Board thicknesses supported, Number of
layers supported, Types of substrates (e.g., material, flexible, rigid),
Geographical location, and more...
Sunday 17
 This very large crossword puzzle will keep
you busy for a while. Since 2000, I have been creating custom
technology-themed crossword puzzles for the brain-exercising
benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. The
jury is out on whether or not this type of mental challenge helps keep your gray
matter from atrophying in old age, but it certainly helps maintain your
vocabulary and cognitive skills at all ages. A database of thousands of words
has been built up over the years and contains only clues and terms associated
with engineering, science, physical, astronomy, mathematics, chemistry, etc. You
will never find a word taxing your knowledge of a numbnut soap opera star or the
name of some obscure village in the Andes mountains. You might, however,
encounter the name of a movie star like Hedy Lamarr...
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