See Page 1 |
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4 | 5 of the November 2020
homepage archives. Monday 30
 I swear when I perused the December 1955
issue of Radio-Electronics there was a good reason that I tagged this "Your
Receiver as an Audio Generator" article for posting, but I'll be danged if the
motivation for it is obvious now. There's nothing undeserving about the subject
from the perspective of a reader back in the day when test equipment could be hard
and/or expensive to come by. In fact, as with many of the articles selected this
one demonstrates the old maxim about how necessity is the mother of invention. No
less an authority on the value of being able to cobble up test equipment from magazine
articles and a box of spare parts than Mac McGregor, proprietor of Mac's Radio Service
Shop, promotes the practice as an essential skill. Even if you don't find the article
useful, at least there's an
electronics-related comic on the page to entertain you.
 "CRFS has launched a new Winter Webinar Series
aimed at maintaining discussions on key
RF Spectrum topics. Since the international lockdown began during March, and
with the cancellation of sector events, CRFS has provided a virtual stage to educate
and support audiences in the security, defense and spectrum monitoring community.
Adapting to the 'new normal' has seen diverse audiences from across the globe attend
the previous webinars and the CRFS Winter Webinar series will expand on this with
a range of new topics. The webinars will explore the growing importance of Electromagnetic
Spectrum Operations (EMSO) in military Electromagnetic Battle Management (EMBM),
the challenges faced..."
 "Scientists at the U.S. Department of Energy's
(DOE) Brookhaven National Laboratory have begun building a
quantum-enhanced
X-ray microscope at the National Synchrotron Light Source II (NSLS-II). This
groundbreaking microscope, supported by the Biological and Environmental Research
program at DOE's Office of Science, will enable researchers to image biomolecules
like never before. NSLS-II is a DOE Office of Science User Facility where researchers
use powerful X-rays to 'see' the structural, chemical, and electronic makeup of
materials down to the atomic scale. The facility's ultrabright light already enables
discoveries in biology, helping researchers uncover the structures of proteins to
inform drug design for a variety of diseases - to name just one example..."
 Artech House today announced the publication
of
Countermeasures for Aerial Drones by Garik Markarian and Andrew Staniforth.
This comprehensive resource explains the development of UAVs, drone threats, counter-UAV
systems, and strategies to handle UAVs, focusing on the practical aspects of counter-unmanned
aerial vehicle (UAV) systems and technologies. Theory, technical and operational
practice with insights from industry and policing are covered, and the full rogue
drone threat landscape and counter-drone technologies and systems is explored. The
book provides insight into counter-drone strategy, developing effective counter-drone
strategies and measures, as well as counter-drone programs and the regulatory frameworks
governing the use of drones. An New Release price of $111 is being offered for a
limited time...
 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.
 Just as early cellphones (Motorola's Bag
Phone, e.g.) required large carrying cases to contain both the large electronics
and the large battery required to operate the phone, some of the first commercially
available portable personal radio sets came with shoulder straps. Those that didn't
have straps had wheels and a handle. The "walkie-talkie"
(originally called "handi-talkies") designs were first seen during World War II
and then in Korea. In fact, this 1955 article from Popular Electronics was printed
shortly after the end of the conflict in 1953. Don't confuse the radio-based portable
field telephones with the ones that had a pair of wires (sometimes thousands of
feet of it) that did not need complicated circuitry for over-the-air transmitting
and receiving...
 ConductRF is continually innovating and
developing new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test Cables
for labs. ConductRF makes production and test coax cable assemblies for amplitude
and phased matched VNA applications as well as standard & precision RF connectors.
Over 1,000 solutions for low PIM in-building to choose from in the iBwave component
library. They also provide custom coax solutions for applications where some standard
just won't do. A partnership with Newark assures fast, reliable access. Please visit
ConductRF today to see
how they can help your project!
Sunday 29
 For the sake of avid cruciverbalists amongst
us, each week I create a new crossword puzzle that has a theme related to engineering,
mathematics, chemistry, physics, and other technical words. This November 29th
Radio &
Radar Crossword Puzzle, as always, 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., Hedy Lamarr or the Bikini Atoll).
The technically inclined cruciverbalists amongst us will appreciate the effort.
Enjoy!
Friday 27
 National Union Radio Corporation, located
in Orange, New Jersey, had been producing radios since its formation in 1929 when
this Radio Service Data Sheet for its
Model G-619 "Presentation" tabletop set appeared in a 1947 issue of Radio-Craft
magazine. That they survived the Great Depression which began in the year of their
founding is a testament the tenacity of its management, design staff, and production
workers. This 5-tube radio had a very nice mahogany case with a unique reverse-lettering
dial glass plate. A few years ago I posted an advertisement by Union Radio from
a 1945 issue of Radio-Craft appealing specifically to women engineers and technicians
because of the severe shortage of men available while serving in the armed forces
during World War II...
 "Army scientists have developed a first-of-its-kind
antenna that could change how ground vehicles and airborne systems communicate,
transmit, and receive radio frequency communications. The Army matured a manufacturing
process using a special class of engineered materials known as metaferrites to make
an
ultra-thin wideband antenna. The antenna conforms to curved surfaces, making
it ideal to integrate in unmanned aircraft systems, rotary wing aircraft, and ground
vehicles. Said Dr. Philip Perconti, Deputy Assistant Secretary of the Army for Research
and Technology and Chief Scientist for the Army, 'Our technical experts used their
knowledge in material properties, modeling, and test and evaluation to further advance
these materials..."
 60 years ago, when this article was originally
published in Popular Electronics magazine, most computers were constructed
either of gears or of vacuum tubes. The Univac in the photo below was a breakthrough
for having been
built entirely of transistors. Even with its "compact" size compared to is successor
the ENIAC, the total computational power and programmability was orders of magnitude
less than that of my handheld calculator, whose size is largely dictated not by
the volume of the electronic circuits, but by the size of the display and the need
for input keys larges enough to press reliably. Doesn't the photo of Pascal's calculator
of 1642 look like it could be a modern 19" rack-mount chassis, complete with handles?
 Modelithics, is pleased to announce the release
of version
20.8 of the COMPLETE+3D Library for use with Ansys HFSS. The library contains
over 325 highly scalable Microwave Global Models™ for capacitor, inductor, and resistor
families from many popular vendors, plus a collection of nearly 300 Modelithics'
3D geometry models for inductors, capacitors, filters, packages and connectors.
This library now represents a total of 22,000 individual components with circuit
and/or 3D EM models. Version 20.8 adds nine new part value-, pad-, and substrate
scalable models and over eighty new full wave 3D electromagnetic models. New scalable
circuit models include new models for AVX's MP01...
 Centric RF is a company offering from stock
various RF and Microwave coaxial
components, including attenuators, adapters, cable assemblies, terminations,
power dividers, and more. We believe in offering high performance parts from stock
at a reasonable cost. Frequency ranges of 0-110 GHz at power levels from 0.5-500
watts are available off the shelf. Order today, ship today! Centric RF is currently
looking for vendors to partner with them. Please visit Centric RF today.
Thursday 26
 Amateur radio enthusiasts are very familiar
with
burying ground radials below the surface (or sometimes just laid on top) in
order to increase antenna efficiency by affecting impedance and, more importantly,
the radiation pattern. Long distance (DX) operators generally prefer low launch
angles over high angle "cloud warmers." Pittsburgh's KDKA, the country's first commercial
broadcast radio station, built what would have been the mother of all ground radial
arrays for its time - 360 (one every degree), 700-foot copper wires (8 AWG), for
a total of a quarter million feet! It was laid using a farm tractor drawing a non-motorized
trench cutter that looks like it came straight from the John Deere factory. It also
implemented a new type of passive vertical suppressor element array...
 "According to a recent report published by
Technavio, the
RF Filters Market is poised to grow at a CAGR of over 20% from 2020 to 2024
to reach USD $15.73B. The report offers an up-to-date analysis regarding the current
market scenario, the latest trends and drivers, and the overall market environment.
According to the report, the market is fragmented, and the degree of fragmentation
will remain the same during the forecast period. The increase in product launches,
organizational restructuring, M&A, and partnerships help market participants
expand their product portfolios, geographic presence, and distribution networks.
Skyworks Solutions Inc., STMicroelectronics NV, Tai-Saw Technology Co. Ltd., Taiyo
Yuden Co. Ltd., and TDK Corp. are some of the major market participants..."
 Here is a specially-made
Thanksgiving Day 2020 crossword puzzle compliments of RF Cafe containing a few
specific words commemorating the holiday along with the usual assortment of engineering
and science related words and clues. Thanksgiving is celebrated in America each
year on the fourth Thursday of November in commemoration of the 1621 feast where
the Plymouth colonists and Wampanoag Indians shared a harvest feast. Macy's 91st
Thanksgiving Day Parade occurs on the morning of Friday, November 26th and follows
a route along Central Park West and 6th Avenue. Interestingly, the parade was cancelled
during the World War II years of 1942, 1943, and 1944 in order to conserve
much needed raw materials. This year, 2020, it will be a hollow event with no spectators
allowed along the parade path...
 Since 1961, MECA
Electronics has designed and manufactured an extensive line of
RF & microwave components
for in-building, satellite, radar, radio, telemetry, mobile radio, aviation &
ATC. Attenuators, directional & hybrid couplers, isolators & circulators,
power dividers & combiners, loads, DC blocks, bias-Ts and adapters & cables.
MECA has long been the 'backbone' of high performance wired and air-interfaced networks
such as in-building applications, satellite communications, radar, radio communications,
telemetry applications, mobile radio, aviation & air traffic communications.
Wednesday 25
 Listen to the RF
Cafe Podcast! A November edition of "Mac's
Radio Service Shop" is appropriate given today's date, especially since author
John T. Frye nearly always had the story's setting coincide with the month
in which it appeared in Radio & Television News magazine; the year
was 1951. The unspecified dateline is somewhere in the upper Midwest, most likely
Indiana. Mac's mention of converting a black-and-white television set to color by
installing a "color wheel" really betrays the era. The NTSC (National Television
System Committee) had not yet adopted an industry standard for color TV, and the
various manufacturers were selling a mix of mechanical, electro-mechanical and all-electronic
sets. In 1953, the NTSC settled on a 525-line interlaced scan (only 468 lines are
part of the visible scan). Knowing that a better color system would be available
soon due to massive public demand, Mac put his efforts into talking customers out
of a color conversion...
 Stephen Barthelmes of Triad RF Systems talks
amplified radios, Doherty techniques, SDR, and UAVs with everythingRF. We talk
about everything from amplified radios and Doherty techniques to software defined
radio (SDR) systems and UAVs in an interview with everythingRF this week. everythingRF:
Can you give us a brief history about Triad RF? Stephen Barthelmes: Triad
RF was established in 2010 when the idea for the company began. In 2013, Dave, Dean
and I got together to begin the development of RF products that were underserved
by the market. By bringing the decades of knowledge that we had accumulated together,
we implemented solid processes in sales, design and manufacturing that produced
products that were cutting edge in performance and cost. We also understood the
market pressures for increasing RF power to enhance data transmission while simultaneously
improving overall efficiency. We stepped up to that challenge by creating some of
the most linear and efficient amplifiers in the market...
3D NAND Hits 176 Layers
 "Micron
Technology recently unveiled
176-layer, triple-level-cell (TLC), 3D NAND flash memory with a 30% smaller
die size that employs a new replacement-gate (RG) NAND technology. The chips offer
a 35% read/write latency improvement as well as a 33% increase in transfer rate,
which is now 1600 Mtransfers/s. The chips are actually built from a pair of 88-layer
stacks. When making a 176-layer stack, the challenge is the difficulty in ensuring
uniform construction up and down the stack. The latest chips follow on the heels
of the 128-layer device from Micron, which also employed 3D NAND and 64-layer stacks.
The challenge that RG NAND addresses..."
 Computer modeling of antenna radiation patterns
has evolved from a relatively simple electric field equation that diminishes as
the inverse of the distance from the source, to exotic, highly sophisticated numerical
methods that account for conducting and dielectric surfaces and volumes. A spreadsheet
can be built rather quickly to calculate and graph the free-space azimuth and elevation
e-field patterns for a 1/4-wave whip or a dipole antenna using textbook formulas,
but building a model for displaying the 3D radiation patterns of a cellphone placed
next to a human head, or a UHF radio antenna on top of an aircraft takes some pretty
serious computing power. In large part we owe a debt of gratitude to the Ph.D. types
who have labored hard to make such tools available to us commoners. As with PCB
layout software and circuit simulators, chances of success with a first pass prototype
has increased...
 Sam Benzacar of Anatech Electronics, an RF
and microwave filter company, has published his November newsletter that features
his short op-ed entitled "Do
You Think 5G is Challenging? Meet 6G!," which delves into what can be expected
based on current planning. "Like its predecessor, 6G is more than simply an upgrade
in data rates and capacity, as it will attempt to deliver downstream data rates
up to 1 Tbye/s and operate at frequencies in the so-called sub terahertz region,
just below where lightwave frequencies begin. It will make extensive use of artificial
intelligence and machine learning to enable applications that 5G presumably will
not have been addressed in the next decade." . Also included in the newsletter are
a few industry headlines...
 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!
 Triad RF Systems designs and manufactures
RF power amplifiers and systems.
Triad RF Systems comprises three partners (hence 'Triad')
with over 40 years of accumulated knowledge of what is required to design, manufacture,
market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA,
bi-directional, and frequency translating amplifiers are available, in formats including
tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology
partner than a vendor for our line-of-sight communications product line." Please
check to see how they can help your project.
Tuesday 24
 Each month Radio-Electronics magazine
ran a column called "'What's New?," which contained a few products recently introduced
to the marketplace, production floor, research laboratory, etc. First up was the
introduction of wire wrapping as announced by Bell Telephone Laboratories a couple
years earlier (see Bell Labs full-page ads in Radio-Electronics and
Radio & Television News in 1953). Wire wrapping is still used today for
quickly prototyping circuits that are not too sensitive to crosstalk and super high
speed. Next was the announcement of a five-transistor pocket radio from a Japanese
company named Tokyo Tsushin Kogyo, which you know today as Sony. Heathkit had recently
put out a build-it-yourself analog computer that used 65 vacuum tubes for $750 ($7,342
in 2020 money). A button-hole-size transistor radio was also reported...
 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.
 "Superconducting
materials are traditionally classed into two types: s-wave and d-wave. A third type,
p-wave, has long been predicted. Now, however, researchers in the U.S., Germany
and Japan say they may have discovered a fourth,
unexpected
type of superconductor: g-wave. The result, obtained thanks to high-precision
resonant ultrasound spectroscopy measurements on strontium ruthenate, could shed
fresh light on the Cooper pairing mechanisms in so-called unconventional superconductors.
In conventional superconductors, electrons join up to form Cooper pairs that then
move through a material without any resistance. While all known superconducting
materials need to be cooled to ultralow temperatures (or placed under extreme pressures)
before their electrons start behaving in this way..."
 Magnetic ceramics have been with us for a
long time - probably forever as far as most people that use them these days are
concerned. When this article was published in a 1953 issue of QST magazine,
ferrites for use at RF frequencies were a new, breakthrough phenomenon. Take a look
at inductors used in vintage radio equipment and you will find either air or solid
iron as the permeable filler elements in most instances. Whereas iron might have
a permeability of 100-150, the new magnetic ceramics exhibited permeabilities up
to 4,000 at 1 MHz, and even higher for lower frequencies. Modern alloys and
compounds provide permeabilities of more than 50,000 for special applications. Such
high values allow physical size and weight of inductors and transformers to be greatly
reduced. Also, since high permeability...
 ConductRF
hand-formable RF coaxial cables are available off the shelf from DigiKey. ConductRF
FM series of Hand Formable RF cable assemblies provides system designers with a
versatile solution that allows RF cables to be physically routed and set in to position
during installation. Standard lengths and connector types feature performance up
to 18 GHz. Low loss, tinned braided cable of 0.086" diameter with shielding
of >100 dB. 100% factory tested for VSWR & insertion loss. RoHS &
Reach compliant. Ideal for internal module linking and great for RF Testing. When
compared to traditional semi-rigid options, these cables can provide increased installation
flexibility at a substantially lower cost. Made in the USA!
 Copper Mountain Technologies develops innovative
and robust RF test and measurement solutions for engineers all over the world. Copper
Mountain's extensive line of unique form factor
Vector Network Analyzers
include an RF measurement module and a software application which runs on any Windows
PC, laptop or tablet, connecting to the measurement hardware via USB interface.
The result is a lower cost, faster, more effective test process that fits into the
modern workspace in lab, production, field and secure testing environments.
Monday 23
 Here in the February 1947 issue of Radio-Craft
magazine is part three of a six-part series on
Antenna Principles. The first two parts concentrated on dipole antennas and
feeders, and multi-element long-line and rhombic antennas. Part three is on directional
arrays and radiation fields. In addition to a bit of theory, real-world examples
are given of various directional antenna configurations along with field strength
graphs. Without powerful computers to calculate and plot out predicted radiation
patterns, a large combination of experience and in-situ measurements was required.
A huge amount of time was spent for even relatively simple arrays. Finitely detailed
topographical and structural models are now available which, along with very precise
electromagnetic field calculation algorithms allows efficient and accurate planning...
 "The first fully integrated single-chip digital
millimeter-wave (mmW) beamformer, created by electrical and computer engineers
at the University of Michigan, opens up new possibilities in high-frequency 5G communications.
The technology could be used to improve vehicle-to-vehicle communication, autonomous
driving, satellite internet, and national defense, to name a few. Beamforming allows
a device that is transmitting signals to point them in a particular direction, as
opposed to having the signals radiate out in all directions - which can lead to
significant interference and loss of efficiency. It is an essential technique for
mmW communication, which occurs at a relatively high frequency (typically between
24 and 100 GHz). This high frequency communication allows for high-speed data
transfer, one of the key advantages of 5G..."
Lotus Communication Systems began in 2009,
setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex
Country, Massachusetts. Lotus is committed to highest quality and innovative products.
Each RF/microwave module meets exceedingly
high standards of quality, performance and excellent value, and are 100% MADE IN
USA. Lotus' RF/microwave products cover frequency band up to 67 GHz. Lotus also
offers an COTS shield enclosures for RF/microwave prototyping and production. All
products are custom designed. We will find a solution and save your time and cost.
Lotus has multiple 4 axis CNC machines and LPKF circuit plotters.
 The
December 2020 issue of QST magazine contains an article reprint from the
February 1971 issue entitled "A
Ham in the People's Paradise*." It was written by Ham radio operator and
USS
Pueblo sailor Ralph McClintock (K1SCQ) who, along with 82 shipmates, were taken
prisoner by North Vietnam on January 23, 1968. He gave a first-hand account of captivity
that lasted until December 23rd of that year. The following year
Hanoi
Jane had her smiling face photographed while posing atop an anti-aircraft gun
when visiting VC troops, while
John McCain
was still at the Hanoi Hilton.
The USS Pueblo incident is most famous for "The
Digit Affair" where crewmembers routinely gave the middle finger in propaganda
photographs broadcast by the North Vietnamese. The men told their VC captors it
was a Hawaiian good luck symbol - until scumbag TIME magazine published the photos
and explained what they were really doing, resulting in severe punishment of the
men. The media has been traitorous for a long time.
(* login required - find a member to access it for you).
 Triad RF Systems has announced the development
of a dual, bi-directional amplifier that supports 2X2 MIMO radio applications.
Model TTRM2005D is a solid-state-power amplifier (SSPA) that operates at a frequency
of 2,200-2,500 MHz. It is designed for military and commercial use and supports
a variety of signal types, from simple CW/FM signals to complex, highly modulated
carriers such as 64 and 256QAM. The technical features of each channel on this dual
bi-directional amplifier includes a transmit signal gain of 25 dB, a receive
signal gain of 12 dB, a receive signal noise figure of 2.5 dB, and ~20 W
BPSK power x2 (40 W off total RF power). Supply voltage is an ultra-wide 12-30 VDC...
 Atenlab has been operating in Taiwan for
more than a decade, and has sold and installed hundreds chambers around the world.
Holistic, affordable Over-the-Air (OTA) measurement
systems perform comprehensive measurement and test in a controlled environment.
Compact Antenna Test Range (CATR) with one-touch operation supports multiple systems
- 2G, 3G, 4G, 5G - and major instrument brands. [M]ulti-probe OTA measurement systems
offer reduced time measurements over single-probe systems.
Sunday 22
 For the sake of avid cruciverbalists amongst
us, each week I create a new crossword puzzle that has a theme related to engineering,
mathematics, chemistry, physics, and other technical words. This November 29th
Electronics
Engineering crossword puzzle, as always, 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.,
Hedy Lamarr or the
Bikini Atoll). The technically
inclined cruciverbalists amongst us will appreciate the effort. Enjoy!
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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