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4 of the November 2019 homepage archives. Friday 8
 You wouldn't know it from the title, "The
Bell Bull Session," but this Carl and Jerry technodrama features a very interesting
subject - the
Shive Wave Machine. The "Bull Session" part of the title is
self-explanatory; it's the "Bell" part that is a reference to Bell Telephone
Laboratories, and specifically to a gentleman named Dr. John N. Shive, who was
Director of Education and Training there. Being avid amateur radio operators and
electronics experimenters, Carl and Jerry were very familiar with the concept of
traveling waves and impedance matching. The Shive Wave Machine is an ingenious
device that provides a visual physical representation of a traveling wave and
how an impedance mismatch generates...
 Airwave Advisors
president and founder Nick Foster wrote asking to have his cell tower consulting
company added to a few RF Cafe vendor pages (Antennas,
Technical
Services, Wireless).
According to his website, "We are the nation's leading cell tower lease experts
and the only accredited cell tower lease consulting company in the United
States to hold an A+ rating with the BBB. We assist private landowners, commercial
real estate owners, municipalities, and anyone else who either has a cell tower
lease, or has been contacted for a new cell tower lease." This might be a good resource
for cell planners. Airwave Advisors is located in Carlsbad, CA, and can be reached
at 858-216-2649.
 IEEE WIE Forum USA East 2019, being held
in Arlington, VA, from November 21st to 23rd, "focuses on developing and improving
leadership skills for individuals at all stages of their careers. Attendees will
have the opportunity to hear inspirational and empowering talks presented by successful
leaders from IEEE Northeast. Emerging technologies will also be demonstrated, engaging
attendees to facilitate discussion and potential advancement of STEM outreach class
ideas." Programs motivate positive progress in career and life, help advance career,
life, leadership, team and career management. Workshops on skills and concepts for
STEM pre-university outreach, and a career fair will be held for students and professionals ...
 Custom MMIC continues the rapid expansion
of its standard product portfolio with three new additions to its
GaAs MMIC mixer portfolio. The CMD312, CMD313 and CMD253 are wideband GaAs
double balanced mixers, operating from 4 to 28, 6 to 45 and 6 to 14 GHz
respectively. These new MMICs are intended to support emerging wide bandwidth
applications in Test Equipment, Instrumentation, Aerospace and Defense. All
three mixers feature low conversion gain and high isolation performance. They
are offered in die form, with a packaged version already available in the CMD253
and planned for the CMD312 and CMD313...
 "A team of researchers from the Massachusetts
Institute of Technology (MIT) has devised a way to pick up and manipulate extremely
small electronic components found in cutting-edge technology. Using a tiny 'electroadhesive' stamp, researchers can now pick
up and put down objects that are as minute as 20 nanometers wide. That's roughly
1,000 times finer than a strand of human hair; this technology could prove extremely
useful as the components in our devices get smaller and smaller in size. The high-tech
stamp is made from an assortment of ceramic-coated carbon nanotubes. The tubes are
placed so they stick up, like the bristles found in a toothbrush. A small voltage
is sent through the stamp ..."
QuinStar Technology designs and manufactures
mm-wave products for communication, scientific, and test applications
along with providing microelectronic assembly, rapid prototyping, and mass customization.
Amplifiers, Oscillators, Switches, Attenuators, Circulators, Isolators, Filters,
Waveguide, Antennas, Phase Shifters, Transceivers, Mixers, Detectors. QuinStar specializes
in cryogenic amplifiers, circulators, and isolators. Please
visit QuinStar today to see how they can help your project.
Thursday 7
 The opening line of this
Transistor Terminology Puzzle states it is the tenth anniversary of the invention
of the transistor, but that is because the crossword appeared in a 1958 issue of
Radio & TV News magazine. It was just before Christmas of 1947 that
Drs. John Bardeen, Walter H. Brattain and William Shockley announced their
discovery from Bell Laboratories. Note that 1947 is eleven years earlier, not
ten. However, the theme of this crossword seems to reference the bipolar
junction transistor (BJT), which was developed in 1948 - hence the 10th
anniversary claim. The first transistor was a point contact type. Print out the
page and have a go at it...
 I haven't owned a digital watch in decades.
My
Timex Expedition WR100M analog watch has taken
a lick'n and keeps on tick'n for about a decade (paid ~$25), but upon seeing this
article about the
Retro Timex T80 on Interesting Engineering website, I thought
maybe a digital watch might be a nice change. Not really remembering the original
T80, I did a Google and eBay search for it and could not locate a good image of
the 1980s version. Some claim to be originals, but the "www.timex.com" stamped into
the back cover is a dead giveaway. $75 is a bit out of my price range for a watch,
so I'll keep a lookout on eBay. You, however, might prefer a new retro version.
If nothing else the battery probably lasts longer than on the original. They don't
seem to be available quite yet.
 Black Friday is known to most modern-day people
as the frenzied first day of Christmas shopping season on the day after Thanksgiving
. It is named so because supposedly on that day many retailers finally turn the
ink in their accounting books from red to black. However, there was an infamous
Black Friday that occurred in the Fall of 1869, when the U.S. stock market experienced
a severe crash. Many know of the 1929 crash that precipitated The Great Depression,
but the other Black Friday, per this historical article from a 1948 edition of
QST magazine, caused its own "great depression" in wireless communications
pioneer Dr. Mahlon Loomis. His reaction is understandable after reading
this piece...
 Berkeley Nucleonics Corporation (BNC) is
an established test equipment company having served the industry for 55 years. With
headquarters in San Rafael, CA, Berkeley Nucleonics is looking for a highly motivated,
detail-oriented, and energetic
Junior Sales Account Manager to help increase the company's U.S. market presence
and support sales growth in the U.S. and internationally. Job duties include but
are not limited to: Support sales and marketing activities, such as quotes, prospecting,
data mining, and event follow up. Support and grow the company's house accounts
in test & measurement equipment sales, as well as a network of independent sales
representatives. Understand customer needs and develop solutions...
 Artech House today announced the publication
Emitter Detection and Geolocation for Electronic Warfare, by Nicholas O'Donoughue.
This comprehensive resource provides theoretical formulation for detecting and geolocating
non-cooperative emitters. Implementation of geolocation algorithms are discussed,
as well as performance prediction of a hypothetical passive location system for
systems analysis or vulnerability calculation. Comparison of novel direction finding
and geolocation algorithms to classical forms are also included. Rooted in
statistical signal processing and array processing theory, this book also
provides an overview of the application of novel detection and estimation
algorithms to real world problems in EW...
 "The U.S. Army is pushing ahead with plans
to field a cannon with an astounding
1,000-mile+ range. The cannon, along with hypersonic
weapons, will allow the service to attack long range, strategic-level targets far
beyond the reach of existing Army systems. According to Defense News, the Army's
program manager for long range fires, Col. John Rafferty, the service expects the
gun to have a range of 1,000 nautical miles - or 1,150 statute miles. The technology
behind the cannon is described as 'cutting edge' that's so advanced that the service
is not sure if the gun would be affordable. The Army is set to conduct an early
test of a key tech component at Naval Support Facility Dahlgren in Virginia 'very
soon ..."
 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.
Wednesday 6
 Author William Blair lamented in a 1958 issue
of Radio & TV News magazine that helix (aka helical) antennas had not
yet been widely adopted by amateur radio operators despite the advantages they can
provide. Helix antennas are used for transmitting and receiving circularly polarized
electromagnetic waves. An advantage of using a
circularly polarized antenna for receiving is that it is able to make use of
wavefronts arriving at any polarization angle along the propagation axis,
thereby accommodating transmissions at any polarization angle. Theoretically, an
ideal antenna with a particular polarization would not receive a signal arriving
at an angle perpendicular to it, and the strength of any signal would be
proportional to the cosine of the angle of impingement...
 Copper Mountain Technologies has produced
a series of on-demand seminars covering topics useful to users of their
vector network analyzer (VNA) product line. This one entitled, "Calibrating VNAs," is an important step in making
accurate measurements with vector network analyzers. "We find many people have good
questions on the proper calibration of USB VNAs. We felt this topic was so important
that CMT Senior RF Design Engineer Brian Walker conducted a webinar about the different
types of calibration for network analyzers. The types of calibration that were covered
were: SOLT/SOLR Calibration TRL Calibration Waveguide Calibration He also reviewed
in the webinar how the standards for calibration ...
 Now
in its third year, Space Tech Expo 2019 | Europe is the EU's major dedicated supply-chain
and engineering event for manufacturing, design, test and engineering services for
spacecraft, subsystems and space-qualified components. Running from November 19
through 21 in Bremen, Germany, the exhibition and conference draw attendance from
thousands of industry leaders, decision makers, engineers, specifiers and buyers
to meet manufacturers across the supply chain for civil, military and commercial
space. If you are involved in the design, production, manufacture, or launch of
Smallsats applications, this event is designed specifically for you ...
 As a follow-on to the "Planning Integrated
Signal Communications" story, this article is the next step in the U.S. Army Signal
Corps' implementation of
ubiquitous communications systems. Along with powerful transmitters and
super-sensitive receivers at command communications hubs are the many hand-held,
back-pack, and vehicular radios needed to complete strategic and tactical
operations across the face of the Earth. It wasn't just wireless systems that
Signal Corps engineers and technicians were responsible for, but also all the
wired equipment and interconnecting cabling. The possibility of software
configuration for network switches, radios, modems, telephones, antennas, and
ancillary components had never been thought of in 1950 (by very few, anyway).
Everything was set up with patch panels...
 Teledyne Paradise Datacom (Paradise), part
of the Teledyne Defense Electronics Group, is unveiling a new
Pulsed Radar SSPA that is designed for Operators of defense-related tactical
radar systems. The solid state technology provides an ideal pathway for customers
seeking to upgrade or replace their existing legacy radar platforms with a newer
generation of technology, one that delivers superior SWaP, power density,
scalability, and performance over a longer life cycle. Additionally, it reduces
the risk of complete loss of service for the Operator. Importantly, the new 4kW
X-band SSPA is configurable to meet diverse radar platform requirements, and
scalable either up or down to effectively address other power levels as desired.
It provides operators of legacy TWT, magnetron, or klystron...
 When I first saw this image I thought is
was a CAD drawing of a vacuum tube amplifier, but, alas, it was merely plans for
a 250 MWh energy storage facility in the EU. "Cryogenic
energy storage pioneer Highview Power, a past winner in The Engineer Innovation
Award, has announced plans to build its first full-scale plant - which will also
be the largest energy storage plant in Europe - at a decommissioned thermal power
station site in the North of England. Known as a Cryobattery, the site will have
a capacity of 50 MW / 250 MWh, Highview says. Announced at the BloombergNEF
summit in London yesterday by Highview CEO Javier Cavarda, the plant will use technology
demonstrated ..."
 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
Tuesday 5
 Today if you need a
printed circuit board (PCB) for prototyping, there is a good chance you will
look up a quick-turn company like those found on the PCB Directory website like
Bittelle, San Francisco Circuits, or a host of other providers. Costs can be a
little as $40 to $50 for three, 3" x 3", 2-layer PCBs and can be delivered in a
week or less. A 4-layer PCB of the same size would cost somewhere around $100.
Considering how much circuitry can be squeezed into a 9 inch2 board these days,
board with surface mounted components on both sides, that's a lot of board for a
little money. If you are really in a hurry for your boards, the fabrication
companies offer various levels of expedited service for more $$$. There are some
people who for one reason or another still prefer to make their own PCBs. For
them, this article from Popular Electronics magazine might be a good resource
for how to go about it. All the necessary materials like ferric chloride and
copper clad substrate material...
 RF Cascade Workbook 2018 is the next phase in the evolution
of RF Cafe's long-running series, RF Cascade Workbook. 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...
 Diode characteristics and their applications
have not changed fundamentally since this article was published in 1952. Sure, the
die are smaller, power handling and frequency range has increased, package styles
are greatly expanded, and the cost per unit is way down, but if you are looking
for some basic diode information, you will find it here in this 4th installment
of a multi-part series in Radio & Television News magazine. Don't
let the vacuum tubes in schematics scare you off and think that it makes the
story irrelevant for today's circuits. For purposes of illustration substitute a
transistor's collector (or drain) for the tube's plate, a transistor's base (or
gate) for the tube's screen grid, and a transistor's emitter (or source) for the
tube's cathode...
  RF Cafe
visitor Shiv Prasad Tripathy, "hands-on engineering practitioner who provides consulting &
knowledge services to people in the academics and industry," has authored a new
book (September 2019) entitled, "RF & μWave Measurements: For Design, Verification
and Quality Control." The old adage about not being able to judge a book by
its cover might be true, but if the book's content is a cool as the cover, it will
be very well done. The book "covers concepts, applications, and measurement techniques
for widely used RF measurement parameters." Included are "signal properties &
modulation, linear & non-linear device models, measurement techniques, plus
instrument families - all with a balanced mix of theory and practical information,
ample illustrations, mathematical treatment and practical examples."
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.
 "DARPA's Spectrum Collaboration Challenge may
have proved the idea is feasible, but there's a long way to go for AI-managed spectrum
sharing. 'You've graduated from the school of spectral hard knocks,' Paul Tilghman,
a U.S. Defense Advanced Research Projects Agency (DARPA) program manager, told the
teams competing in the agency's Spectrum Collaboration Challenge (SC2) finale on
23 October. The three-year competition had just concluded, and the top three teams
were being called on stage as a song that sounded vaguely like 'Pomp and Circumstance'
played overhead ..."
 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. Take a couple minutes to visit their website and see how
IPP can help you today.
Monday 4
 People are entering the field of electronics
all the time and many want to learn not only
circuit theory and troubleshooting, but design as well. With all the pre-packaged
integrated circuits available that perform just about every function imaginable,
there are still times when you either want or need to set about designing your own
circuit. Interfaces between two circuits, or to displays and sensors are examples
of the kinds of applications that might need a custom design. That applies not only
for RF type circuits that require impedance matching, but also to low frequency
analog and digital circuits. This article by Mr. Jim Huffman, which appeared
in a 1972 issue of Popular Electronics, provides an introduction on how
to methodically determine all necessary requirements and then actually design
your circuit - in this case an audio amplifier. A technician I worked with in
the early-to-mid 1980s who was an inspector at Westinghouse Oceanic Division...
 Artech House today announced the publication
Introduction to
Radar with Python and MATLAB®, by Andy Harrison. This comprehensive resource
provides readers with the tools necessary to perform analysis of various
waveforms for use in radar systems. It provides information about how to produce
synthetic aperture (SAR) images by giving a tomographic formulation and
implementation for SAR imaging. Tracking filter fundamentals, and each parameter
associated with the filter and how each affects tracking performance are also
presented. Various radar cross section measurement techniques are covered, along
with waveform selection analysis through the study of the ambiguity function...
 Bittele, a turn-key PCB assembly services
provider for prototype and low volume electronic contract manufacturing, has posted
a tutorial entitled, "How to Design Cost-Effective PCBs." It begins, "A design engineer
should consider all the things that affect the total cost of manufacturing of PCB.
Frequently, new PCB design engineers often do not consider the cost of PCB fabrication.
The things that affect the cost per PCB that many young design engineers don't plan
for include the cost of tooling, the size of a PCB and the spacing of board components.
To ensure that your production costs are as low as possible, including the costs
of tooling, here are some guidelines to follow: 1. Select the smallest size of the
PCB that is practical. 2. Standard rectangular and square PCB shapes always cost
less than non-standard shapes. Furthermore, do not incorporate slots or cutouts
unless they are completely necessary ..."
 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.
 MECA Electronics, Inc., a leading supplier
of passive RF, microwave, and mm-wave products for public safety, wireless, 5G cellular,
military, and VSAT/SATCOM, has introduced a 380 MHz to 2.700 GHz, 30 watt
average power (5 kW peak) 50 Ω termination with very low passive intermodulation
(PIM) specifications. The model
LPT30-4310M is rated for -161 dBc PIM (typical) at 30 watts. It is verified
at 1900 MHz at -155 dBc minimum. Thermally compensated to handle full rated
power to 85°C. N-type connector standard...
 IEEE COMCAS
2019 is being held in Tel Aviv, Israel, from November 4th through 6th. COMCAS
2019 continues the tradition of providing a multidisciplinary forum for the exchange
of ideas, research results, and industry experience in areas such as communications,
antennas, Radar, RF and Microwave Circuits and Systems, and Bio-medical Engineering.
"Following the previous COMCAS conferences, we expect more than 1600 participants
from about 40 countries around the world." IEEE COMCAS 2019 will deal with issues
including: Innovations in Technology, Digital AESA Radar, MW Circuits modeling and
Simulation, Space Oriented technology ...
 "5G promises to deliver massive improvements
in network capacity by utilizing new 5G frequency spectrum in both sub-6 GHz
and 24-40 GHz millimeter-wave (mm-wave) frequency bands. Antenna Company's
5G solutions include antenna systems for 5G small cell, gNodeB and fixed wireless
applications. Our mm-wave designs combine Antenna Company's patented
SuperShape™ and DRA technology to achieve wide-band
operation over the 24-30 GHz frequency bands. Our designs are scalable to support
37-40 GHz frequency bands for global band support across the mm-wave spectrum ..."
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.
Sunday 3
 Each week, for the sake of all avid cruciverbalists
amongst us, I create a new
technology-themed crossword puzzle using only words from my custom-created lexicon
related to engineering, science, mathematics, chemistry, physics, astronomy, etc.
This one is for November 3, 2019. 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, see someone or something in the exclusion list who or that is directly
related to this puzzle's theme, such as Hedy Lamarr or the Bikini Atoll,
respectively. Enjoy...
Friday 1
 Admittedly, I did not do any follow-up research
on this, but there is reason to believe that prior to this Radio News magazine
article, there was not a general agreement on what formula to use for thermal noise
in an electrical system. Here is a statement made by author S.J. Mallory, "At
first, however, there was no general agreement concerning the magnitude of this
basic Johnson noise power level. Some engineers used the quantity KTB, others used
2KTB and still others used 4KTB." We of course all use KTB nowadays for thermal
noise power - aka
Johnson noise. It's a good read on the subject of sources that determine the
noise floor of a system. There's also this kind of Johnson noise...
 Global MilSatCom 2019 Conference and Exhibition
will be held from November 5th through 7th, in London, UK. Global MilSatCom is Europe's
leading military communications event for satellite professionals. Hosted by SMi
Group over 3 days, Global MilSatCom is once again set against sweeping developments
for numerous national sovereign SATCOM programmes; in particular, the development
of the host nations SKYNET constellation - but also across key allied programmes
such as WGS, SATCOMbw, MUOS, SICRAL and SYRACUSE. How this sovereign bandwidth can
be pooled and augmented with COMSATCOM also remains essential as NATO is set to
sign a memorandum of understanding ...
 The November 2019 issue of
QST (login required) is chock full of great
articles. The one entitled, "Indoor Antennas for VHF Weak-Signal Work," written
by Mr. Les Rayburn (N1LF) discusses ways to stealthily mount an antenna in
your attic in order to work around HOA restrictions and/or to protect your installation
from weather abuse. Considering the close proximity to living quarters, he offers
caveats and mitigation suggestions regarding RF exposure during transmission and
subjection to high noise levels from his own home and from nearby neighbors. The
notable line pulled from the article is, "Neighbors equal noise." The situation
gets worse every day. Here's my own
attic-based
TV/Radio antenna installation.
 Basic
transformer circuits have not changed in the more than sixty years since this
article was published in Popular Electronics magazine. The applications
have definitely changed, though, since active circuits of the day required a
relatively low voltage (step-down) for vacuum tube cathode heaters, and at least
one relatively high voltage (step-up) for biasing the tube plate. Most
transformers for today's consumer applications perform a single step-down
operation for 3.3 V, 5 V, 12 V, etc. In many applications, transformers are done
away with altogether in favor of solid state rectifiers and regulators. A
5-question quiz is provided at the end. There is also a short tutorial on
electrostatic speakers and some analog and digital signal info. Digital circuits
were still a relatively new (and scary) concept to most people at the time...
 Since 1999, Win Source has been assisting
customers with an ability to quickly and accurately find obsolete, end-of-life,
hard-to-find parts, and
acquire authentic common-used parts at competitive prices. A consistently optimized
in-stock inventory of more than 500,000 parts and a global network of suppliers
to reduces your procurement cycles, lower transaction costs and provides quality
electronic components at competitive prices. Distribution centers are maintained
in Hong Kong, Singapore, Philippines, China, Japan. Win Source has been added to
the RF Cafe Obsolete
Components Vendors page.
 "To handle the demands of
Industry 4.0, high speed, ultra-low latency,
and maintenance-free operation are important parameters. Here's a mmWave-based solution
for slip-ring assemblies that meets those needs. The fourth industrial revolution
drives digital manufacturing forward by implementing new scenarios into the production
process. These scenarios rely on fundamental design principles that include device
interconnection, information transparency, technical assistance, and decentralized
decisions. The realization of all these principles in modern smart factories would
not be possible without advanced wireless ..."
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.
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. I also
have an extensive list of
Recently Added topics.
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