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5 | of the July 2020 homepage archives. Tuesday 7
 British engineer John Sargrove was to the
production of radios what Henry Ford was to automobiles. At the time this "Robot
Makes Radios" article appeared in a 1947 issue of Radio-Craft magazine, Sargrove
had recently put his
Electronic Circuit Making Equipment (ECME) fully automated assembly line into
operation. Applying knowledge from two decades of developing methods of crating
inductors, capacitors, resistors, and interconnecting conductors using controlled
deposition of various materials on flat substrates, he was able to build 2-tube
AC/DC radios at a rate of up to three per minute, with only two ECME operators -
one at the input and one at the output. The only manual assembly required was the
installation of a potentiometer-switch, a transformer, speaker...
 The U.S. Federal Communications Commission
published a
Ground
Conductivity Map for the continental United States in 1975, and it is still
the most current version. No doubt more modern ground conductivity equipment and
methods could produce a more detailed and accurate map, but for general purposes,
this suffices. When more precise local soil conductivity measurements are required
by electric utilities, communications installations, etc., teams of technicians
and/or engineers are dispatched to obtain measurements. Many moons ago (early 1990s)
while doing a short stint at the Potomac Edison Electric Company in Hagerstown,
Maryland, our electric substation guys had some pretty impressive measurement gear
that used probes pounded into the ground in multiple locations to gets resistance
(conductivity) readings between them. Where the soil conductivity is not sufficient
to meet specifications with simple ground rods and/or meshes, chemical agents would
be spread around the area...
 RF Cascade Workbook 2018 is the next phase in the evolution
of RF Cafe's long-running series, RF Cascade Workbook. Chances are you
have never used a spreadsheet quite like this. 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...
 If
subjects pertaining to electronics - particularly vacuum tubes - are like music
to your ears, then this poem entitled "What Is It?," from the February 1943 edition
of QST, should suit you just fine. The rhyming words are supplied by author
Frank Judd; you just need to supply the harmony. You might recognize paraphrasing
of other familiar works such as Longfellow's "Paul Revere's Ride." Poems like this
one were actually quite common back in the day. In fact if you look through the
list of articles that I have posted from vintage QSTs, you will find about
a dozen...
 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. Available in single
or multi-junction topographies, the Nova Microwave product line of is specifically
designed for use in varied environmental and temperature extremes.
 If you had to guess, what would you say the
image to the left represents? Part of a printed spiral inductor? How about a printed
antenna for near field communications (NFC)? Need a hint? OK, the object is part
of a project that Alexander Graham Bell, his cousin Chichester Bell, and Charles
Sumner Tainter worked on in their Volta Laboratory Associates labs. No, it's not
a neatly wound coil of telephone cable. It is a section of an audio
recording
etched on a glass platter in November of 1884. After being stored at the Smithsonian
Museum for 130 years, this and a few other recording media was lent to the scientists
at Lawrence Berkeley National Laboratory with hopes that they could apply newly
invented noninvasive, non-contact techniques to scan the disc and use software algorithms
to recover the data. Thomas Edison had introduced his phonograph to the world in
1877...
 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.
Monday 6
 Before there were electric generators onboard
airplanes to power communications equipment, aviators relied on storage batteries
to operate their radios. Before that, there were no radios at all aboard airplanes.
Although Wilbur and Orville Wright first piloted their Wright Flyer in 1903, by
the end of the decade airplanes were becoming a common sight across the country
and across the civilized world. By the middle of the second decade experiments were
being done with airborne radio. They were heavy vacuum tube units with heavy
lead-acid batteries. Antennas sometimes hundreds of feet long needed to be reeled
out and in once at altitude. The earliest transmitter (for 2-way communications)
were spark gap types, meaning of course Morse code was the medium. That's right,
the pilot - often alone without an assistant - sent messages by tapping out dits
and dahs using a straight key strapped to his thigh. Moving into the 1920s, radio
telephony had become standard equipment aboard transport and military aircraft.
Much of it early-on was battery powered...
 NorthEast RF provides quick-turnaround
antenna testing services for IOT and M2M
devices. Either passive antenna measurements, or OTA cellular device pre-compliance.
We supply 2D | 3D antenna patterns along and antenna efficiency measurements in
a report along with a data file for use with a pattern viewer. The near-field antenna
test system is ideal for either free space or verification of body worn devices
using our selection of human head and hand phantoms. NorthEast RF's comprehensive
antenna testing services include linear | circular polarized antenna measurements
and OTA cellular device pre-compliance. Antennas can be rapidly evaluated and optimized
using our fast near field spherical system. Test results supplied in data file with
pattern viewer software. Turnaround time is usually 3-days. Please take a few minutes
to see how they can help your project.
 "A high-resolution paramagnetic resonance
detection method based on the diamond nitrogen-vacancy (NV) color center quantum
sensor was proposed and experimentally implemented in a study led by academician
DU Jiangfeng from CAS Key Laboratory of Microscale Magnetic Resonance of University
of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS).
The researchers obtained the
single-spin paramagnetic resonance spectrum with kilohertz (kHz) spectral resolution.
The study was published in Science Advances. A major development trend of electron
paramagnetic resonance spectroscopy is to get as accurate information as possible
from as few samples as possible, which requires enhancing..."
 San Francisco Circuits (SFC), a provider
of
PCB fabrication and assembly, announces they are fully compliant with the National
Institute of Standards and Technology (NIST) Special Publication 800-171 requiring
companies to adhere to specific guidelines to protect data and information pertaining
to federal or state agencies. Being in compliance ensures proper data handling is
in place for maintaining the trust of partners, vendors, contractors, and customers–especially
when federal or state agencies are involved. The federal government requires companies
to be compliant with 800-171 to protect Controlled Unclassified Information (CUI).
CUI is sensitive information relevant to the interests of the United States government...
 Bill Schweber's article on the Electronic
Design website entitled, "Watch
Out, MEMS Switches - Much-Smaller NEMS Relays Are Coming After You!" shows once
again that every new paradigm-changing miracle product and method is eventually
trumped and rendered obsolete. "Using phase-change materials, researchers have devised
a nanoscale metal-contact on/off switch that doesn't use a flexure element and is
far smaller than its MEMS-based counterparts. There's no doubt that devices based
on MEMS (microelectromechanical systems) processes and technologies have radically
changed the world of sensors and solid-state functions. Since they became commercially
viable in the 1980s beginning with analog airbag impact-acceleration sensors...
 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.
Sunday 5
 This week's custom RF Cafe crossword puzzle
celebrates the 244th anniversary of the signing of the
Declaration
of Independence, and uses as a background the John Trumbull painting. Clues
marked with an asterisk (*) are part of the theme. Each week for two decades, for
the sake of all avid cruciverbalists amongst us, I have created a new technology-themed
crossword puzzle using only words from my custom-created lexicon related to engineering,
science, mathematics, chemistry, physics, astronomy, etc. You will never find among
the words names of politicians, mountain ranges, exotic foods or plants, movie stars,
or anything of the sort. You might, however, find someone or something in the otherwise
excluded list directly related to this puzzle's technology theme...
Friday 3
 As I have written often, Hugo Gernsback was
one of the electronics industry's most prolific authors, inventors, and innovators.
In this 1947 article in his Radio-Craft magazine, he proposes using
printed components in place of leaded resistors. In fact, he sold printed resistive
cards through his Radio Specialty Company (Rasco) that could be cut into whatever
size was needed to achieve the required amount resistance based on a certain ohms/square
value. He also mentions creating printed inductors on Bakelite and even fashioning
variable-coupling transformers with a pair of inductor plates sliding relative to
each other, similar to capacitive "variometers" used for tuning RF circuits. Not
to neglect the possibility of capacitors, Gernsback suggests possibly spraying a
thin conductive coating on paper and then rolling multiple layers into a tubular
form, achieving a smaller form factor per unit capacitance that what was currently
being achieved. Single- and double-sided printed circuit boards were already being
used for some high volume, compact portions of assemblies, and he proposes improving
methods to eventually...
 Copper Mountain Technologies has released
the new Compact S5045 and M5045 VNAs with a frequency range from 9 kHz to 4.5 GHz.
Featuring a dynamic range of 130 dB typ. and measurement speed of 70 µs,
these new
Compact VNA offerings will effectively replace the functionality of the recently
discontinued S5048, while delivering improved performance. The S5045 will come with
the advanced software features engineers expect from CMT's S Series Compact VNAs.
The M5045 will join the M Series line of Compact VNAs and include standard VNA software
features in an economical package that excludes a number of advanced software features...
 "SES, leader in global content connectivity
solutions, announced its selection of two U.S. satellite manufacturers, Northrop
Grumman and the Boeing Company, to deliver four new satellites as part of the company's
accelerated C-band clearing plan to meet the Federal Communication Commission's
objectives to
roll-out 5G services. Northrop Grumman will deliver two flight-proven GeoStar-3
satellites, each equipped with a high-quality C-band payload to deliver the superior
customer experience that end users are accustomed to. The two satellites - SES-18
and SES-19 - will be designed, assembled and tested in Dulles, Virginia. The Boeing
Company will deliver a pair of highly efficient all-electric 702SP satellites. The
two satellites - SES-20 and SES-21 - will be manufactured and assembled in Los Angeles,
California..."
 The
Dog Days of Summer,
contrary to what many people believe, is named not to describe the hottest, most
humid, most oppressive period of the year, but marks the astronomical point in time
following the heliacal rising of the star system
Sirius, aka the Dog Star in the
constellation Canis Major.
40 days later, on August 11th, the Dog Days end. That also happens to be middle
of summer (not midsummer),
which is on or about August 6th. Never having been a proponent of summer, the end
of the Dog Days has always meant we're closer to the end of summer than to the beginning,
and autumn is on the way.
 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 (of course a gratuity will be graciously
accepted). 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 ...
 Do you remember seeing a cool Doodle on
the Google search page and would like to find it again? Would you like to see not
only the Doodle that piqued your interest, but ALL of the Doodles that Google has
ever published? You can do that, but what might be more useful would a page full
of all the technology- and science-related Doodles (click large image below) or
some other specific topic. Fortunately, there is an easy way to find what you want
by going to the Google website and typing "google doodles"
into the search box, or just go to www.google.com/doodles. Once you get there, enter
the specific event that interests you. Since some events have Doodles in more than
one year, add a year to your search to narrow down returns...
 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 of normal circuit board providers.
Please take a moment to visit San Francisco Circuits today. "Printed Circuit Fabrication &
Assembly with No Limit on Technology or Quantity."
Thursday 2
 "Transatlantic
News" was a regular column in the 1940 issues of Radio-Craft magazine,
written by their European correspondent Major Ralph Hallows. As the title suggests,
it reported on happenings from across the pond. A couple items caught my attention
in this edition. One is about one of the first instances of the prediction of existence
of a D-Layer in the ionosphere based on radio signal propagation characteristics
noted by operators. The article estimates a height of about 30 miles, while the
modern definition of the D-Layer places it at between 60 km (37 mi) to 90 km (56
mi). It also has a piece describing a simple method for silver plating without the
need for supplying an electrical current. It involves making a paste of silver chloride
and cream of tartar (potassium bitartrate) and rubbing it on the target metal. Supposedly
the bond is as durable as electroplating...
 Lou Frenzel
has an article on the Microwave & RF website entitled, "It's
All About the Antennas for 5G." He begins: "For 5G technology to function as
expected in apps from factory automation to self-driving vehicles, multiple antennas
must be properly implemented. When studying 5G NR operation, it's not immediately
obvious that 5G meets all of the objectives of the 3GPP standard by using advanced
antenna technology. Antennas are often overlooked and treated with indifference.
After all, antennas are just that nuisance metal thing that you have to put on a
radio to make it work. In the case of 5G, antennas play a major role in achieving
the expected features and performance. The primary objectives of 5G NR are..."
 Since 1996, ISOTEC has designed, developed
and manufactured an extensive line of RF/microwave connectors, between-series adapters,
RF components and filters for wireless service providers including non-magnetic
connectors for quantum computing and MRI equipments etc. ISOTEC's product line includes
low-PIM RF connectors components such as power dividers and directional couplers.
Off-the-shelf and customized products up to 40 GHz and our low-PIM products
can meet -160 dBc with 2 tones and 20 W test. Quick prototyping, advanced
in-house testing and high-performance. Designs that are cost effective practical
and repeatable...
 The "Radio
Terms Illustrated" comics was a pretty clever feature in Radio-Craft
magazine in the 1940s. Readers submitted ideas about how words and phrases commonly
used in electronics and communications could be rendered in comical picture form.
Illustrator Frank Beaven, who did work for many magazines of the day, then put pen
to paper to render the kinds of comics shown here. You will note that the first
of the drawings, "Amplitude," is one which probably would not pass editorial review
these days, but was de rigueur back in the days when men made up the vast majority
of readers. By today's standards many advertisers would face a threat of boycott
and a front-page apology would be demanded... and then the magazine would be forced
out of business anyway. There is no satisfying "the mob." Utter destruction of the
past is their goal. To show how extreme...
RF Cascade Workbook 2018 is the next phase in the evolution
of RF Cafe's long-running series, RF Cascade Workbook. Chances are you
have never used a spreadsheet quite like this. 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...
 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. Please visit Allied
Test Equipment today to see how they can help your project.
Wednesday 1
 As is the case with most genius inventors
who change the world,
Lee de Forest's contribution to the world of electronics neither began
with nor ended with his invention of the Audion amplifying vacuum tube. As detailed
in many of the other articles published in the January 1947 edition of Radio-Craft
magazine that commemorated the 40-year anniversary (see ToC), de Forest's path
from a simple open flame type of demodulator to the ultimate design of the evacuated
glass-encased Audion tube with plate, control grid cathode, and heater element required
many years of trial and error. The stories were so captivating that I actually read
every article in this edition. Eventually, I will have all of them posted. This
particular piece by Fred Shunaman reports on some of the many other innovative,
patented inventions of de Forest such as antenna transmission lines (twin lead and
coaxial), radio signal detector...
 Artech House today announced the release
of "Cognitive
Radar: The Knowledge-Aided Fully Adaptive Approach," Second Edition by Joseph
R. Guerci. Hurry to get the discounted new-release price. This highly anticipated
second edition of the bestselling Cognitive Radar: The Knowledge-Aided Fully Adaptive
Approach, the first book on the subject, provides up-to-the-minute advances in the
field of cognitive radar (CR). Adaptive waveform methods are discussed in detail,
along with optimum resource allocation and radar scheduling. Chronicling the field
of cognitive radar (CR), this cutting-edge resource provides an accessible introduction
to the theory and applications of CR and presents a comprehensive overview of the
latest developments in this emerging area...
 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!
 Good, clean humor has always been a welcome
addition to my day whether it comes in the form of a printed comic strip, a TV show,
or someone's mouth. My father's side of the family was populated with many jokesters
who could be counted on to deliver an ad hoc pun or zinger at the appropriate moment.
The environment instilled a great appreciation for such entertainment, so these
electronics-themed comics that appeared in editions of Radio-Electronics,
Popular Electronics, et al, are a refreshing distraction from the workaday
world. An old saying claims "laughter is the best medicine," and while it cannot
cure cancer, a good dose of humor often helps ease the pain...
 Fractals
have been a mathematical curiosity since first being popularized by Benoit Mandelbrot
(who coined the term) in the 1960s. Perhaps, and in retrospect no coincidence, was
the popularity of the cloaking concept featured in the 1960s phenomenon called Star
Trek. I say coincidence because who would have guessed that some of the leading
research in invisibility cloaking would involve barriers derived from fractal forms?
Have aliens been guiding the technology? If so, maybe they're working at
Fractal Antenna Systems,
because in mid December the company issued a press release detailing work being
done on a cloaking system that works in the microwave band (as opposed to visible
light) - chosen for convenience...
 RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave component
supplier. RF coaxial connectors & adapters, coaxial cable & cable assemblies,
surge protectors, attenuators. Items added daily. Free shipping on orders over $25.
We're leading the way again!
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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