See Page 1 |
2 |
3 |
4 |
5 of the October 2019 homepage archives. Friday 18
 That Hugo Gernsback was a prolific writer,
inventor, visionary, designer, and builder is unquestionable given the huge number
examples of each that can be easily found on the Internet and in libraries. Gernsback
was never bashful about giving himself credit for technology predictions when thy
come to fruition and for the coining of new terms. In this "Reversible
Television" editorial column that appeared in a 1948 issue of his Radio-Craft
magazine, Gernsback claims to have been the first to use the word "television" in
a technical article - but not necessarily having invented the term. He did have
an idea for a "Telephot," a portmanteau of "telephone" and "photograph." The
device would take the form of phone with a built-in video display to allow
parties to view each other whilst...
 A few days ago I posted an article from a
1935 article in Short Wave Craft magazine entitled, "Put
Your Aerial Underground." Upon seeing it, RF Cafe visitor Jean-Marie Polard
(F5VLB), located in France, sent me a note about his very impressive Facebook page
that contains a lot of information on
Earth Probes Used As Antennas.
Evidently there is a large contingent of radio amateurs, at least in Europe,
still experimenting with and successfully using the method. As with many areas
of wireless communications, Ham operators worldwide are continuing to push back
the technology frontiers...
 It's Friday again already (...finally). In
that these
comics from Radio-Craft magazine have an electronics theme, you can
claim looking at them is work-related. The themes of the comics reflect common
scenarios of the 1944-1945 era in which they were published, but with not much
modification can be applied to today's environment. People will always expect
more features from products, will be critical of everything presented to them,
and will want to haggle for the best deal from the used camel salesman. You
might consider using one of them for your next conference or project status
presentation. Enjoy...
Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave
filters, diplexers, and sub-assemblies. They offer the generally known tubular,
LC, cavity, and waveguide designs, as well as state of the art high performance
suspended substrate models. Through a continuous process of research and development,
they have established a full line of filters of filters of all types - lowpass,
highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact
Reactel today to see how they might help your project.
 "Recently discovered two-dimensional (2D)
materials with superlative properties have the potential to advance semiconductors
but creating 2D devices with both good electrical contacts and stable performance
has proved challenging. A nearly ideal transistor made from a
two-dimensional material stack - with only a
two-atom-thick semiconducting layer - was fabricated using a completely clean and
damage-free fabrication process. The method shows vastly improved performance compared
to 2D semiconductors fabricated with a conventional process and could provide a
scalable platform for creating ultra-clean devices in the future. The two-step,
ultra-clean ..."
 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 use their modern engineering, testing and packaging facility
to help your project.
Thursday 17
 This photo from an article entitled, "Exploring
Electronics with Simple Projects," which appeared in a 1958 issue of Popular
Electronics magazine, made me think of "The Radio Boys" series of books written
in the 1920s. A shorter series entitled "The Radio Girls" appeared as well. Both
titles told tales of a group of youngsters who were caught up in the "wireless"
craze of the era. They built their first receivers entirely from homemade parts,
including winding the tuning coil and fashioning a moveable tap on the coil.
Motivated by more knowledgeable adults - of which there were few in the day -
the kids progressed on to single-tube sets and then, after earning their
licenses, built and operated transmitters. Today such do-it-yourselfers are
called "Makers," and there is an entire industry and culture...
 Exodus Advanced Communications is pleased
to introduce our high power 10 kHz to 100 MHz 1000-watt, class A/AB linear
LDMOS, rack mountable amplifier.
Exodus AMP2080E-1 produces 1000 W minimum, >1100 W nominal power, P1dB 700 W
typical. The minimum power gain is >60dB with excellent gain flatness. Included
are amplifier monitoring parameters for Forward/Reflected power, VSWR as well as
voltage, current & temperature sensing for optimum reliability & ruggedness for
all applications. Nominal weight is 120 lbs., and dimensions of 19"W x 30"L x
17.5"H...
 All
RF
Cafe quizzes would make perfect fodder in employment interviews for technicians
or engineers - particularly those who are fresh out of school or are relatively
new to the work world. Come to think of it, they would make equally excellent study
material for the same persons who are going to be interviewed for a job. This quiz
is based on the information presented in High-Frequency Integrated Circuits, by
Rosin Voinigescu.
 Sam Benzacar of Anatech Electronics, an RF
and microwave filter company, has published his October newsletter that features
his short op-ed entitled "Coming:
Plasma Antennas." Plasma antennas have been appearing in the news items I
collect, and Sam does a pretty good job summarizing their operation and
benefits. One feature I do not recall seeing elsewhere is that in the "off"
state, the plasma antenna presents a very small radar cross section (RCS), which
is strategically advantageous for stealth aircraft (and surface ships). In other
news, Sam includes other news related to our RF industry...
 Please
take a few moments to visit the
everythingRF website to see how they can assist
you with your project. everythingRF is a product discovery platform for RF and microwave
products and services. They currently have 227,460 products from more than 1210
companies across 285 categories in their database and enable engineers to search
for them using their customized parametric search tool. Amplifiers, test equipment,
power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers,
power supplies, and everything else. Please visit everythingRF today to see how
they can help you.
 "Today's cellular networks and Wi-Fi systems
rely on microwave radiation to carry data but the demand for more bandwidth is quickly
becoming more than microwaves can handle. That has researchers thinking about transmitting
data on higher frequency terahertz waves, which have as much as 100 times the data-carrying
capacity of microwaves. But
terahertz communication technology is in its
infancy - there is much basic research to be done and plenty of challenges to overcome.
It's been assumed that terahertz links would require a direct line of sight between
transmitter and receiver ..."
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.
Wednesday 16
 According to an item in this late 1944 issue
of Radio News magazine, the six-hour delay which occurred between the time
the armistice was signed at the end of World War I and the time news reached
the battlefields, many men, women, and children on all sides died needlessly. Almost
as many were maimed or injured. That might seem like a stretch, but in the 4 years,
3 months, and 2 weeks of the "the war to end all wars," an estimated 14 to 19 million
lives were lost. It is an average of 375 to 500 casualties per hour, or 2,200 to
3,000 in six hours. Planners expected that the widespread availability of
wireless communications (radio) meant that when the end World War II was
finally announced, a cease fire on all fronts would be effected in less than
half an hour...
Characterizing Uncertainty in S-Parameter
Measurements
 A team of authors from the Federal Institute
of Metrology (METAS), Berne-Wabern, Switzerland, have published an article in Microwave
Journal entitled, "Characterizing Uncertainty in S-Parameter Measurements,"
which poses - and answers - the question, "If it is that easy to take two measurements
and obtain different results, how can one know which measurement is correct?" "Every
measurement, no matter how carefully performed, inherently involves errors. These
arise from imperfections in the instruments, in the measurement process, or both.
The 'true value of a measured quantity' (atrue) can never be known and exists only
as a theoretical concept. The value that is measured is referred to as 'indication'
or (aind) ..."
 Unlike other websites, I never require you
to provide personal information in order to access someone else's (or my own) app
notes / whitepapers. The app note entitled "Introduction to SAW Filter Theory & Design Techniques,"
by API Technologies, can be downloaded directly from the company website without
registration. It begins, "In theory, an ideal filter would possess no loss, an instantaneous
transition from the pass band to the stop band, infinite stop band attenuation,
no signal distortion introduced by the filter and have very small size and cost.
In reality, many tradeoffs need to be considered when selecting a filter for a system
design. An advantage of SAW filter technology ..."
 At VidaRF, the phrase 'Providing Simple
Solutions for Complex Connections' is more than just a slogan – it's a mindset,
a mission, and a driving force behind everything we do. Their pledge is to design
and distribute high performance, cost effective
RF Microwave products to fit each customer's unique applications.
Please visit VidaRF today to see how their lines of Attenuators & Terminations,
Directional Couplers, Power Dividers, Coaxial Connectors, and Circulator & Isolators
can be of use to your project. "When the standard just will not do, VidaRF has the
solution for you!"
 Just as the test and measurement equipment
manufactures scrambled to produce lines of spectrum, network and communications
analyzers, oscilloscopes, power meters, electromagnetic field sensors, and many
other types of products specifically for the cellphone and Wi-Fi industries, companies
were scrambling to provide for the needs of FM radio and television development
labs and production lines. This 1947 advertisement from
Radio
Corporation of America (RCA) is an example that appeared in Radio News
magazine. In fact, TV was so new that just a few months later, in September of 1948,
editor Hugo Gernsback changed the publication's name to Radio
and Television News ...
 "Very
thin nylon films were created that can be used
in electronic memory components. The films are several hundreds of times thinner
than a human hair and could be used in bendable electronic devices or for electronics
in clothing. Nylon synthetic polymers consist of a long chain of repeated molecular
units in which each repeated unit contains a specific arrangement of hydrogen, oxygen,
and nitrogen with carbon atoms. Besides use in textiles, some nylons also exhibit
ferroelectric properties - positive and negative electric charges can be separated
and this state can be maintained. The ferroelectric materials are used in sensors,
actuators, memories, and energy-harvesting devices ..."
 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 (FR-4, Rogers, flexible, rigid), Geographical
location (U.S., China), kinds of services (manufacturing, fabrication, assembly,
prototype), and more. Fast turn-around on quotations for PCB fabrication and
assembly.
Tuesday 15
 If you are a Ham radio operator - especially
a DX (long distance) operator, you have been required to study and learn about how
the various layers of the Earth's ionosphere can, under predictable conditions,
be an excellent reflector of certain radio wavelengths, thereby facilitating
over-the-horizon communications. Reading this article is like a flashback from
the license preparation manuals - particularly for the General license exam. There
is a lot of information here. When this article was published in a 1958 issue of
Radio & TV News magazine, the world was nearing the end of the International
Geophysical Year (IGY), which had as its goal learning as much as possible about
the properties of the upper atmosphere. The first earth-orbiting satellites were
being launched and manned space flight was only months away, so there was much interest
in learning ...
 Rohde & Schwarz has published an app
note entitled, "dB Or Not dB?" (a rather contrived attempt -
yet not unlike something I might try to get away with - at an allusion to Shakespeare's
"To be or not to be..."). The subtitle is, "Everything you ever
wanted to know about decibels but were afraid to ask..." It begins, "%, dB, dBm
and dB (μV/m) are important concepts that every engineer should understand
in his (or her) sleep. Because if he does not, he is bound to be at a disadvantage
in his work. When these terms come up in discussions with customers or colleagues,
he will have trouble focusing on the real issue if he is busy wondering whether
3 dB means a factor of 2 or 4 (or something else). It is well worth the effort to
review these concepts from time to time and keep familiar with them ..."
 A while back, I purchased a May 29, 1948,
edition of The Saturday Evening
Post, because it contained one of Charles Schulz's Li'l Folks (which became
Peanuts) comics. There were a couple things that stood out as I perused the magazine.
First was the vitriolic tone of the Letters to the Editor, ripping the publication
for articles in previous editions. Another was that the majority of the artwork
for stories and advertisements was either a painting or a pencil drawing - almost
no photographs. There was not a single ad for any television set - B&W or color
- even though RCA had been selling color sets for four years by that time. The following
story was on the last page of the magazine. You'll get a kick out of its premise ...
 The 2019 IEEE International Symposium on Phased Array Systems
and Technology will be held from October 15th through 18th at the Westin
Hotel in Waltham, Massachusetts, on Boston's famous Route 128 Technology Highway.
The symposium will include keynote and plenary sessions, parallel technical sessions,
poster sessions, tutorials, and a student paper contest. Social events will include
a welcome reception with dinner and an awards banquet. This symposium will present
the most recent advances in phased array technology and provide a unique opportunity
for members of the international community to interact with colleagues in the field
of phased array systems and technology.
 "After many years of continuous growth, the
global smartphone market saw a slowdown in 2018. This slowdown had a direct impact
on the
RF Front-End market which also saw a decline
in demand last year. According to a recent Yole Développement (Yole) report, 5G
will come to the rescue and drive the RF Front-End market to grow at a CAGR of 8%
from 2018 to 2025. The market was estimated to be USD $15B in 2018, and is expected
to reach USD $25.8 billion by 2025. With LTE, RF front-end market growth came from
carrier aggregation and MIMO technologies. 5G will augment RF front-end market ..."
 Empower RF Systems is a global leader in
power amplifier solutions. Empower RF Systems is an established and technologically
superior supplier of high power solid state RF & microwave amplifiers. Our offerings
include modules, intelligent rack-mount amplifiers, and multi-function RF Power
Amplifier solutions to 6 GHz in broadband and band specific designs. Output
power combinations range from tens of watts to multi-kilowatts. Unprecedented size,
weight and power reduction of our amplifiers is superior to anything in the market
at similar frequencies and power levels.
Monday 14
 Once upon a time, all non-passive electronic
products and test equipment used vacuum tubes. Since tube diodes need a voltage
bias, even something as simple as a rectifier circuit was "active." Even though
modern day
transistorized equipment has largely overcome most of the disadvantages of solid
state versus vacuum tube, in the early days of silicon and germanium transistors
and diodes issues like voltage and power handling and input impedance was a limiting
factor to some applications. Until the advent of rugged and reliable field-effect
transistor (FET) transistors, if you needed a very high input impedance for an oscilloscope
or multimeter, a vacuum tube circuit was a necessity. A high impedance test instrument
input is required with high impedance device under test (DUT) in order to avoid
loading down ...
 The Association of Old Crows is holding their
56th
Annual AOC International Symposium Convention in Washington, D.C., on October
28-30. It is regarded as the industry's leading event and brings together nearly
2000 professionals from 30+ countries spanning industry, military, and government
sectors. "Learn from subject matter experts and influencers from military, government,
academia and industry who will speak to a multitude of topics around the theme of
'Building the EMS Enterprise.' Whether it is from a main stage keynoter, a breakout
session panelist, or an Innovation Stage message, plan to walk away equipped with
the latest developments in technology and governance in pursuit of EMS capability
superiority. ..."
 Here is an advertisement for
Delco
radios that I scanned from my copy of the April 1945 QST magazine.
"'Control the Air' has a new meaning today." That's the tag line referring to the
need to dominate wireless communications in the effort to conduct effective warfare.
Radio certainly wasn't a new science in 1945, but secure communications - including
spread spectrum techniques - was a vital technique both for transmitting and receiving
messages and for jamming the communication of our enemies. Even though Hollywood
actress Hedy Lamarr and music composer George Antheil came up with the concept of
frequency hopping spread spectrum in the early years of World War II, the U.S.
Department of War stuck mostly with codebook encryption techniques ...
 This article entitled "Avoiding Electrical Damage with Conductive Lubrication"
appeared in the October 2019 edition of NASA's Motion Design publication.
It highlights the new problems being faced by automotive design engineers as they
replace 12 V electrical systems, which have been the standard for over half
a century, with increasingly preferred 48 V systems. The motivation (pun not
intended) is, among other things, to enable use of smaller gauge wire, and the resulting
lower weight and expense, in the ever-increasing amount of electrical cabling in
modern vehicles. The downside of a higher voltage is a larger difference of potential
induces larger leakage currents in metallic components without bonded connections
- as in bushings and ball bearings. Engineers and scientists are now developing
conductive lubricants to help mitigate the problem ...
 "Imperfections in diamond enable a 10-qubit
register - a collection of qubits that can store data in a
quantum computer - report researchers at Delft
University of Technology in the Netherlands and Element Six in the UK. Their diamond-based
system is capable of preserving an arbitrary single-qubit state for over a minute
- a record for a solid-state qubit. The multiqubit register signifies important
progress in quantum-information processing, which requires a large number of qubits.
Realizing multiqubit registers is challenging for two reasons: the quantum gates
require selective control of qubits, and unwanted interactions must be avoided ..."
 Anatech Electronics (AEI) manufactures and
supplies RF and microwave filters for military and commercial communication
systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters,
and RF products. Standard RF filter and cable assembly products are published in
our website database for ease of procurement. Custom RF filters designs are used
when a standard cannot be found, or the requirements dictate a custom approach for
your military and commercial communications needs. Sam Benzacar's monthly newsletters
address contemporary wireless subjects. Please visit Anatech today to see how they
can help your project succeed.
Sunday 13
 For two decades, I have been creating custom
engineering- and science-themed crossword puzzles for the brain-exercising benefit
and pleasure of RF Cafe visitors who are fellow cruciverbalists. This October 13,
2019, puzzle contains the names of at least eight advertisers* who help
deliver RF Cafe to you every day. Otherwise, it uses a database of thousands of
words which I have 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 or a geographical location like Tunguska,
Russia, for reasons which ...
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.
Homepage Archive Pages
2025:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2024:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2023:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2022:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2021:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2020:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2019:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2018:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2017:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2016:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2015:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2014:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2013:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2012:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 (no archives before 2012)
- Christmas-themed
items
|
