Before most people listened to radio and television
programming via cable, satellite, and/or the Internet, broadcasts were received
over the air, usually from local stations. A common problem in the days of vacuum
tube Ham transmitters back in the day was inadvertently causing broadcast interference
(BCI) or specifically in the case of television, TVI, due to insufficient
filtering, shielding, or design. Nowadays, we generally refer to all such unintentional
and incidental radiation as radio frequency interference (RFI). Lots of articles
were written on the subject in the 1940s through about the 1970s. Some RF spectrum
is shared by more than one entity per FCC and other countries' band plans, with
primary and secondary allocations assigned
...
"Northrop Grumman unveiled its vision of
the so-called sixth-generation fighter, showing reporters a
laser-firing aircraft that looks like a cross between the B-2
bomber and the X-47B drone. Chris Hernandez, Northrop's vice president for research,
technology and advanced design, laid out the basic parameters for the sixth-gen
fighter (Northrop refers to it as
NG Air Dominance): it must boast long range because it's
unlikely to have many bases to operate from overseas; it must 'carry a lot of weapons;'
survivability will be key. What do those requirements and physics lead you to? 'This
looks a lot like a baby B-2 and this is really
..."
Z-Communications-Intros-1715-1745-MHz-VCO-10-15-2015.htm" >
Z-Communications, Inc. announces a new RoHS compliant
VCO model
USSP1730-LF in the L-band. The USSP1730-LF operates from 1715
to 1745 MHz within a tuning voltage range of 1 to 4 Vdc. This remarkable
VCO features phase noise of -94 dBc/Hz @ 10kHz offset while operating off a
5 Vdc supply and typically drawing only 19 mA of current. The low cost
USSP1730-LF provides the end user a nominal output power of 3.5 dBm into a
50Ω load while operating over the industrial temperature range of -40 to 85ºC. This
high performing VCO Z-Communications-Intros-1715-1745-MHz-VCO-10-15-2015.htm" ...
anatech-december-2015-newsletter.htm" >
Anatech Electronics, a manufacturer of RF and
microwave filters, has published its December 2015 newsletter. As always, it includes
both company news and some tidbits about relevant industry happenings. This month,
Sam Benzacar theme is "Connected Cars: More Interference Sources?," where he discusses
the history and current state of Advanced Driver Assistance Systems (ADAS) and vehicle
autonomy. The government can't keep it's fleet of Amtrak trains on the tracks and
prevent them from colliding with each other; their role in autonomous cars should
be wonderful anatech-december-2015-newsletter.htm" ...
"Personally, I liked the University. They
gave us money and facilities, we didn't have to produce anything. You've never been
out of college, you don't know what it's like out there. I've worked in the private
sector. They expect results." Dr. Raymond Stantz (Dan Aykroyd), in
Ghostbusters.
While funny, it must be recognized that a lot of valuable research and applications
adaptable to industry comes from universities and a lot of crap comes from "out
there."
"Ultrafast pump-probe microscopy on individual
vanadium dioxide microcrystals measures the spatial and temporal variability of
ultrafast dynamics of the insulator-to-metal transition. Surprisingly, nominally
identical crystals show dramatically different transition times. Additional results
from nano-imaging (lower right) reveal a complex structure
suggesting high sensitivity to heterogeneous nanoscale features
..."
"These nanopillars would negate the reflective
properties of the metal wires needed for shunting power to and from the device,
thus allowing more photons to pass through the surface. Now, a collaboration among
researchers at the University of Illinois at Urbana Champaign and the University
of Massachusetts at Lowell has yielded another approach to producing nanopillars
on the surface of solar cells that promises to allow more photons through so more
electricity
..."
Next Spring I will be installing an old-fashioned
(but newly manufactured)
Channel Master television antenna on a short tower with a rotator.
Here in Erie, Pennsylvania, under certain conditions I can receive broadcasts from
Erie and many of the cities that border close to Lake Erie like Toronto and Waterloo,
Canada and even Detroit. AM radio stations are easily pulled in from the same areas,
but FM does not do quite so well. I plan to also integrate some form of FM antenna
on the installation. There is something insulting about paying for cable or satellite
TV and then having to suffer the deluge of commercials as well
(I have neither). Nobody likes sitting through commercials,
but at least if the programming is being delivered at no cost, it is not unreasonable
for the broadcast
...
"Does every era have a characteristic disease?
After all, demonic possession was all the rage in the Middle Ages: these days, not
so much. In Victorian times, female hysteria was a common diagnosis. More recently,
we've seen a variety of 20th century candidates Multiple Chemical Sensitivity, Parental
Alienation Syndrome, and the peculiarly French affliction known as jambes lourdes
(heavy legs), which can be relieved by drinking lots of tea or walking in the ocean.
For the Internet Age, though, we need a disease more appropriate to an
..."
A lot of
career
advice has been published in the three months since I last posted a list like
this. A lot of what's out there does not really apply to the typical RF cafe visitor
(i.e., intelligent, resourceful, technically competent, intolerance of BS), so I
put some effort into vetting these articles before recommending them to you. The
targeted audience ranges from college students looking for their
...
•
Career-Boosting New Year's
Resolutions to Make Right Now
•
The Right - and Wrong - Ways to
Sneak out for a Job Interview
•
How To Pick A Job That Will Keep
Your Brain Healthy
•
How to Translate Book Smarts
into Job Search Success <more>
"Pentagon officials are drafting new policy
that would officially recognize the electromagnetic spectrum as a 'domain' of warfare,
joining land, sea, air, space, and cyberspace, Breaking Defense has learned. The
designation would mark the biggest shift in Defense Department doctrine since cyberspace
became a domain in 2006. With jamming, spoofing, radio, and radar all covered under
the new concept, it could potentially bring new funding and clear focus to an area
long afflicted by shortfalls
..."
In keeping with the holiday movie theme begun
with last week's "A Charlie Brown Christmas," this week's crossword puzzle contains
clues for names of characters appearing in Frank Capra's "It's a Wonderful Life" (all the other words
are engineering and science related as usual), which first aired in movie
theaters in December of 1946. Clues for those characters' names are marked with
an asterisk
...
"Scientists have successfully switched on
the world's largest 'Stellarator' fusion reactor.
Dubbed Wendelstein 7-X (W7-X), the reactor is designed to contain super-hot plasma
for more than 30 minutes at a time. This week, the reactor produced a special super-hot
gas for a tenth of a second. Scientists hope that, if it can work for longer, it
could eventually lead to limitless supplies of clean and cheap energy
..."
These are close-up photos of common household
objects. Your mission, should you decide to accept it, is to identify each one.
Most are fairly easy, but a couple are a little outdated since they appeared in
a 1939 edition of Boys' Life magazine. Answers are way down at the bottom
of the page
...
A short while back I came up with what has
turned out to be a pretty effective way to handle those pain-in-the-donkey
unsolicited telephone calls. We don't have caller ID on our home
phone so we have to answer every time it rings or risk missing a wanted call. It
is well known that once you pick up, the call centers then know yours is a good
number to call so it gets passed on to even more call spammers. Being listed on
the federal "Do Not Call" list is only one line of defense, and does almost no good
for out-of-country sources. Most of the callers will keep talking over you until
you hang up, even after expressing no desire to deal with them. So, what I do now
as soon as I determine it is a spam call is start speaking a list of keywords for
which the FBI, DHS, and other
...
Werbel-Microwave-10-MHz-Laboratory-Grade-Power-Divider-12-10-2015.htm" >
The WMPD08-0.01-X series power divider is a laboratory-grade
10-MHz splitter / combiner
for synchronizing test equipment clock signals. It offers typical channel isolation > 35 dB
(22 dB minimum), maximum insertion loss of 0.6 dB,
and maximum port SWR of 1.25. Phase and amplitude balance are < 1 degree
and < 0.1 dB at all ports. May be customized with BNC, N or SMA
female connectors. Made in USA by Werbel Microwave LLC Werbel-Microwave-10-MHz-Laboratory-Grade-Power-Divider-12-10-2015.htm"
...
These three
electronics-themed comics appeared in the November 1948 issue
of Radio & Television News magazine. You don't need to be of the era
in order to appreciate the humor, but Millennials might need a little assistance
with the second one. That contraption sitting the desk is called a 'turntable,'
and it used to play audio media called 'records' by spinning them at a certain rate
(33-1/3 rpm, 45 rpm, 78 rpm), while
that horizontal lever called a 'tone arm' held a piezoelectric needle in the grooved
tracks of the record. The joke here is the guy having to spin his head while trying
to read the printed label. I'm just joshing the Millennials, of course, since they
use spinning disks called CDs and DVDs for listening to music - or do they? Is everyone
now using solid state
...
"We shop, watch TV and read news on our phones,
so why not apply for jobs from one? Increasingly, we do. Some recruiters say half
or more of their applicants
apply for jobs using their smartphones. "I probably applied
for 90 percent of my positions on my mobile device," says Kirk Coleman of Plano,
Texas. Coleman says he was fine letting his thumbs do the talking, filling out forms
and connecting to his LinkedIn profile. 'Being the generation that I am, a millennial,
people kind of want it here and now. That's the mentality
..."
Pasternack, a leading provider of RF, microwave
and millimeter wave products, expands their waveguide product portfolio with the
addition of new
flexible waveguides that operate up to 40 GHz
over nine frequency bands. This offering consists of 36 unique models of flexible
waveguide twists ranging in size from WR-137 (as low as 5.85
GHz) to WR-28 (up to 40 GHz). Pasternack's
flexible/twistable waveguides, also referred to as a "flexguide," utilize helically
wound silver coated brass strips surrounded by a flexible and twistable, yet durable,
neoprene sleeve Pasternack-Flexible-Twistable-40-GHz-9-Frequency-Bands-12-9-2015.htm"
...
"Strictly speaking,
hexagonal boron nitride is a semiconductor, but its band gap is
so big that, for all practical purposes, it behaves like an insulator. It's because
of this pseudo-insulator characteristic that researchers have been interested in
combining boron nitride with other two-dimensional materials such as graphene to
create hybrid materials capable of doing what each constituent can't do on its own.
Now researchers at the Department of Energy's Oak Ridge National Laboratory (ORNL)
have developed a process for producing a nearly perfect single layer of hexagonal
boron
..."
I have always been a stickler for creating
neat, orderly arrangements when building any type of circuit assembly. Many moons
ago when starting out as an electrician, I made a point of installing straight runs
of Romex type cable with no twists, evenly spaced staples, and keeping the identification
marking to the outside. Conduit was precisely bent and installed, again with organized
parallel runs and even spacing where possible (all while
conforming to the NNEC). Circuit breaker panel wiring looked like something
seen in an Apollo space capsule. Electrical inspectors often complimented my work.
Moving on to an electronics career, the habits carried over when prototyping and
even when directing layout for production PCBs or chassis assemblies, including
cabling. The greatest enjoyment I had was when laying out runs of waveguide
...
"Scientists could soon develop
particle accelerators that can
fit into a shoebox, experts say. The project, which is still in its infancy, would
rely on lasers, rather than microwaves, to ramp particles to near light speed. Using
lasers, 'you can accelerate particles in a shorter distance to get to a higher energy,'
said Joel England, a researcher at SLAC National Accelerator Laboratory in Menlo
Park, California, and one of the principal researchers involved in the project.
The earliest forms of the technology would probably be used for medical physics
and experiments to watch atoms in real time
..."
Electronic Properties of Materials,
by Rolf E. Hummel, is a text on the
electrical, optical, magnetic, and thermal properties of materials
stresses concepts rather than mathematical formalism. Suitable for advanced undergraduates,
it is intended for materials and electrical engineers who want to gain a fundamental
understanding of alloys, semiconductor devices, lasers, magnetic materials, and
so forth. The book is organized to be used in a one-semester course; to that end
each section of applications, after the introduction to the fundamentals of electron
theory, can be read independently of the others. Many examples from engineering
practice serve to provide an understanding of common devices and methods
...
If you are old enough to remember
the 1960s and 70s in America, then surely you recall news and documentary coverage
of extreme pollution levels in major cities like Pittsburgh, Los Angeles, and Chicago.
In many cases the smog looked similar to the way cities like
Beijing and
Delhi do today. This is evidently
the price a society pays for technological advancement. An honest assessment of
the situation concludes that advanced western societies have exported much of their
smog-producing industry to places like Delhi and Beijing. Environmental and human
rights activists here bear some responsibility for the suffering in other countries.
Those activists exploit all the benefits and conveniences of state-of-the-art technology
to get publicity for providing clean water to Saharan tribes at the expense of the
lady in the above picture. Good intentions don't always product only good results.
Reading through this article reminds me of
studying for the amateur radio exams. In fact, the information presented in this
1940 QST piece does not seem to be lacking anything that contemporary discussions
include. My point is that a great amount of knowledge had already been amassed about
earth's
upper atmosphere a mere four decades after the first transatlantic
radio communications were accomplished by
Marconi on December 12, 1901 from Poldhu in Cornwall, England,
to Newfoundland, Canada. Considering that at the time no instrumented sounding rockets
had been launched into the extreme upper layers (F1 &
F2, beginning at around 120 mi | 200 km), a lot had been discerned about
characteristics as they pertain to radio communications. Balloons were
...
Saelig-2-GHz-6-GHz-RF-Vector-Signal-Generators-12-9-2015.htm" >
Saelig Company announces the availability of Triarchy
Techologies' VSG2G1 and VSG6G1
RF Vector Signal Generators - very cost effective USB-connected
portable, pocketable RF signal sources with capabilities that provide features and
functions comparable to full-size analog RF signal generators. Offering frequency
ranges up to 2.2 GHz (VSG2G1) or 6.2 GHz (VSG6G1), frequency sweep, frequency
hopping using I&Q modulation, and arbitrary signal generation are possible.
The compact signal sources can generate most RF signal modulations that RF engineers
might need, since the VSGxG1's many test functions can be customized Saelig-2-GHz-6-GHz-RF-Vector-Signal-Generators-12-9-2015.htm"
...
This article by
Annie Dike, writing for IMS ExpertServices, discusses the concept
of
patent exhaustion (aka the 'first-sale
doctrine') as it applies to copyrights and patents. Not being a lawyer, I
needed to do a little additional research on it to comprehend what was being stated.
International sales complicates an already muddy subject, so much so that even the
U.S. Supreme Court could not agree on its interpretation when deciding cases involving
a third party's right to re-sell a product which had been previously legally purchased.
Ms. Dike's example pertains to a printer company seeking to prevent another company
from re-filling and re-selling its ink cartridges. Another prominent example I found
in a search involved well-known technical book publisher John Wiley & Sons,
whereby Wiley sought to prevent a Thai company
...
"Technology made large populations possible;
large populations now make technology indispensable." –
Joseph W. Krutch, writer and naturalist. Having passed on in 1970, he wrote
this without even imagining how nearly half a century later entire populations would
be walking around with their gazed inexorably fixed on a small, thin communications
box, while being largely unaware of what was happening around them
...
"The fastest
electro-optic THz switch yet has emerged from free electron
laser research at the University of Exeter. Graphene, meta-material and plasmonics-based;
the exotic device can modulate a THz beam to 60% depth at 40MHz. "40MHz is not fast
compared with telecoms modulators, but it is better than state-of-the-art at THz,"
Professor Geoff Nash told Electronics Weekly. It is based on ribbons of graphene,
made by chemical vapour deposition on an oxidised silicon wafer
..."
If you have ever lived in a neighborhood
with a Nazi-like HOA, then you understand how frustrating it can be when you have
to get permission from "the board" for something as innocuous as planting some bushes
in front of your home ... In 1985, the ARRL petitioned the FCC to codify
law that would ensure no governmental agency - local, state, or federal - could
prohibit reasonable installations of antennas for Ham operations ...
As so often happens, over time the original intent of the law has been reinterpreted,
diminished, or outright dismissed by individual agencies and governing bodies to
the point that once again the ARRL found it necessary to petition the government
to clarify and enforce its stance regarding the rights of Hams to build and operate
communications equipment. Its current incarnation is in the form of
The Amateur Radio Parity Act of 2015 ...
Raise your hand if you hate popup ads and
ads that start playing sound. RF Cafe has never knowingly allowed such ads on the
website, but I run into them all the time when searching for daily tech headlines.
Per this
NY Times article, "Ads pop up and play automatically, daring
readers to shut them down with feats of fine motor control. The ads commandeer the
screen. They expand and contract. They cover the text and refuse to budge. From
Our Advertisers And then there is the dreaded X - the one that invites you to close
the ad yet seems impervious to repeated clicks of the cursor or the jabs and
..."
Maybe it isn't so anymore, but according
to Centralab the ceramic raw materials available in abundance in America were electrically
superior to those being used in Europe since the early 1900s when German scientists
first discovered the dielectric properties of the material.
Ceramic capacitors represented a major advance in capacitor technology
over liquid and paste dielectric types in most areas of electrical and mechanical
specifications such as vibration, aging, vibration and shock, temperature, value
stability, voltage and current handling, etc. Centralab ran this advertisement spelling
out all the virtues of ceramic capacitors that had accumulated due to their research
efforts. Philips Electronics' Components division bought
...
It is no secret that I consider Hugo Gernsback
to be one of America's greatest high tech visionaries. Through his many electronics
magazines and books, he has predicted versions of many of the world's inventions
ranging from radar and sonar to hands-free radio, satellite communications, and
even
Google Cardboard. 'Cardboard' is the name given to the inexpensive
yet highly functional 3-D stereo virtual reality (VR) viewers designed to work with
Android and iPhone Cardboard smartphone apps that are formatted to provide 3-dimensional
images. This is a 21st century version of the old View-Master™ toys
(which are still in production). Why do I give Mr.
Gernsback credit for Cardboard? The clipping below from the December 24, 1965 edition
of the Lebanon Daily News in its exaltation of his propensity for
...
"Volunteers aid pioneering
Edsac computer
rebuild - BBC News Think of a shed and objects like spades, forks and compost in
a wooden hut at the end of the garden come to mind. However, in the UK, some very
old hardware is being brought back to life in some of those scruffy, but often well-organised,
workspaces. In them, a group of veteran engineers is toiling to help recreate the
pioneering Edsac computer. Designed by
Sir Maurice
Wilkes, Edsac first ran in 1949 and was made to serve
..."
Keysight%20Technologies-5G-Modeling-Beamforming-Channel-Software-Library-12-3-2015.htm" >
Keysight Technologies today introduced beamforming
and channel modeling capabilities in the Keysight EEsof EDA W1906EP
5G Baseband Verification Library. This advanced
software library dramatically increases productivity for system architects and baseband
physical layer (PHY) designers by providing trusted algorithmic-reference, signal
processing intellectual property (IP) for 5G technology research. Keysight will
demonstrate its 5G Baseband Keysight%20Technologies-5G-Modeling-Beamforming-Channel-Software-Library-12-3-2015.htm"
...
These two
electronics-themed comics appeared in circa 1952-53 Radio &
Television News magazine. For some reason the early 50s were a little comic
challenged. I really like the one with the guy hanging from the antenna! It's hard
to make out the artists' names, but they have appeared on other comics of the era.
If you enjoy comics like this, there is a growing list of other comics at the bottom
of the page you can check out
...
"During the 1960s, computers occupied whole
rooms, but had less power than the PC now sitting in the den of your home. There
weren't even pocket calculators back then. At the top of the Saturn was the Apollo
spacecraft. And one of the most important components inside of the Saturn was its
guidance computer. As Charles Murray and Catherine Bly Cox noted in their seminal
classic
Apollo: The Race to the Moon, 'The computer capacity of
the mainframes in the Control Center [of NASA's Manned Spacecraft Center in Houston]
was smaller than that of the desktop systems of the 1980s, and onboard computers
in the command and lunar modules had less capacity than some pocket calculators
..."
If you have been around RF Cafe or my hobby
website, Airplanes
and Rockets, for any length of time, you probably know of my being a lifelong
fanboy of the Peanuts comic strip, drawn by Charles Schulz. This week's engineering
crossword puzzle contains the names of many Peanuts characters
who appear in the "A Charlie Brown Christmas" animated feature that first aired
on
TV on December 9, 1965, on CBS (all the
other words are engineering and science related). Clues for those characters'
names are marked with an asterisk. If you have never seen
...
Peregrine-Semiconductor-RF-Digital-Phase-Shifter-12-3-2015.htm" >
Peregrine Semiconductor, founder of RF SOI and
pioneer of advanced RF solutions, introduces the UltraCMOS®
PE44820, an 8-bit digital phase shifter that covers a 358.6-degree
phase range. This monolithic, digitally controlled product is easy to design-in
and delivers exceptional phase accuracy and high linearity. Supporting a frequency
range of 1.7 to 2.2 GHz, the PE44820 is ideal for optimizing the transmission phase
angle in the wireless infrastructure and radar markets. It provides reliable and
repeatable RF performance to applications such as antenna beamforming, distributed
Peregrine-Semiconductor-RF-Digital-Phase-Shifter-12-3-2015.htm" ..."
A couple RF Cafe Forums visitors have posted topics
recently in search of assistance. Since the venue is still in its infancy, I will
occasionally highlight activity in hopes of spurring more interaction. A list of
the four most recent forum posts are automatically listed on the RF Cafe homepage.
Presently, "Good source for Ansys Designer help? " and "Installing a Garage Door
Antenna Extension" are at the top. You can participate either by obtaining your
own account login, or anyone can post using the guest username 'guest1' and password 'micro1"
(these are listed on the homepage are are subject to change
as needed). Please contribute in whatever way you can. Thanks.
"Most of the time we are blissfully unaware
of the
2,250 satellites flying above our heads. And
while some are big enough to be seen by the naked eye, keen amateur astronomers
still need to know where to look in the star-studded sky. To make this easier, there
is now an interactive map that shows satellites and pieces of space junk passing
above cities, and even your home and office, in real-time. Created by artist and
engineer Patricio Gonzalez, the 'Line of Sight' map gives a fresh perspective on man-made devices
..."
The ability to generate clean, controlled
radio waves at 3 THz in 1937 was about as attainable as putting a man on the
moon. That did not stop scientists and engineers from theorizing how to get there
and what to do once attained. That's the way science progress happens. An official
name had not yet been given to the spectrum realm, but news reporters conjured up
the moniker "mystery rays." Even scientists called it the "black gap." Both sound
a bit hokey and there is a temptation to poke fun at the renown technical ignorance
of most media types, but no less a science giant as Albert Einstein referred to
quantum entanglement as "spooky action at a distance." The big idea of author W.E.
Shrage was to exploit and extend the concept of a cathode ray tube
(CRT) to convert
...
MegaPhase-Paul-Skolnik-VP-Sales-Marketing-12-3-2015.htm" >
MegaPhase, a leading provider of RF and microwave interconnects,
is pleased to announce that MegaPhase-Paul-Skolnik-VP-Sales-Marketing-12-3-2015.htm" >Paul
Skolnick has joined the company as Vice President of Sales & Marketing. Paul
has spent the last 3 decades in sales engineering, sales management and business
development for RF and Microwave signal processing components and subsystems for
applications in satellite, terrestrial and wireless communications, and electronic
warfare. In Skolnick's prior role as Director of Business Development for Crane
Aerospace and Electronics Microwave Solutions, he led a team of technical sales
MegaPhase-Paul-Skolnik-VP-Sales-Marketing-12-3-2015.htm" ...
Chief-Scientist-IoT-Mobile-Chair-EDI-CON-China-2016-12-2-2015.htm" >EDI CON China is pleased to announce that Dr.
Wai Chen, chief scientist and general manager of IoT at China Mobile, will be the
chairman of EDI CON China
2016, taking place 19-21 April, 2016 in Beijing at the China National Convention
Center (CNCC). Dr. Chen presented in the plenary session of EDI CON 2015 about IoT
Services: "Opportunities and Challenges – A Perspective of a Mobile Operator." He
will lead the plenary session in 2016 with an updated outlook from China Mobile
and their latest activities in the area of IoT Chief-Scientist-IoT-Mobile-Chair-EDI-CON-China-2016-12-2-2015.htm"
...
Skyworks-Low-Power-Bluetooth-Low-Energy-FEMs-12-2-2015.htm" >
Skyworks offers two low-power Bluetooth® low
energy (BLE) front-end modules (FEMs) for connected home, wearable and industrial
applications. The SKY66110-11 and
SKY66111-11 FEMs operate between 2.4 to 2.485 GHz, with power
consumption of only 10 mA in transmit mode. They are suitable for products operating
from coin cell batteries including sensors, beacons, smart watches, thermostats,
smoke and carbon dioxide detectors, wireless cameras and audio headphones, hearing
aids and medical pendants. The FEMs more than double the range when compared to
a standalone system Skyworks-Low-Power-Bluetooth-Low-Energy-FEMs-12-2-2015.htm"
...
Assuming the 10 enumerated advantages of a
gridless vacuum tube may be added to the 17 enumerated disadvantages of a gridded
vacuum tube, there are 27 reasons, per author Henri Dalpayrat why one should consider
abandoning the 'old style' tubes for his revolutionary concept.
Part 1 of this 2-part series discussed the unavoidably negative
features of a gridded vacuum tube. Part 2, presently, extolls the wonders of a gridless
tube. Chief among the features is the use of 'compressor bar' elements that are
situated parallel to the electron flow rather than in series with it. Another major
difference is the cathode element
...
"Tile - Never Lose
Your Keys, Wallet Or Anything Again. Lose less of everything, including your valuable
time. Tile is a tiny Bluetooth tracker and easy-to-use app that finds everyday
items in seconds - like your phone, keys, and wallet." This appeared on one of the
tech news websites I visit (I honestly can't recall which),
and it looked cool enough to pitch on RF Cafe. Clip the Bluetooth dongle to anything
and find it with your phone. Tile also works in reverse - if you have your
Tile but can't find your phone, squeeze Tile and it will ring
your phone. A networking feature of Tile enables anyone in the vicinity
of a Tile to report back to your phone with its whereabouts, whether it
is in someone's office or across the country in a thief's backpack
...
This is the first of a two-part article about
the strengths and weaknesses, pros and cons, vices and virtues of vacuum tubes with
and without grids. Author Henri Dalpayrat offers a list of no fewer than 17 drawbacks
and limitations of gridded tubes. While necessary to fully control the flow of electrons
from the cathode to the plate, their physical presence causes issues with parasitic
capacitance, thermal noise, electrical variability due to physical differences,
increased manufacturing cost, and lower reliability. Eliminate the control grid(s)
and most of those problems go with it. Part 2 was printed in the January issue,
which I happen to own, so I'll try to get that posted within the next couple days
...
Narda-Safety-Test-Solutions-Signal-Guide-Free-12-2-2015.htm" >
Narda Safety Test Solutions is releasing its
private "Signal Guide"
for use free of charge. This database contains typical measurement result images
for many RF signals, which can be considered as the "fingerprints" of the different
signals. By comparing your own result images with the database images, you can distinguish
the pure signals from interference and impairments. Radio and TV, analog and digital,
second, third and fourth generation mobile telecoms, emergency services communications,
WLAN, industrial control signals Narda-Safety-Test-Solutions-Signal-Guide-Free-12-2-2015.htm"
...
Bird-Technologies-SiteHawk-SK-200-TC-Antenna-Cable-Analyzer-12-1-2015.htm" >
Bird Technologies, a leading provider of RF components,
subsystems, test equipment, and services, today introduced the
SiteHawk SK-200-TC hand-held antenna and cable analyzer that
operates from 300 kHz to 200 MHz. The instrument makes it simple to detect problems
in coaxial transmission lines and antenna systems and pinpoint their source using
distance-to-fault measurements. The SiteHawk SK-200-TC provides all of the measurement
capabilities required to evaluate the performance of a communication system's transmission
path, and has the same features Bird-Technologies-SiteHawk-SK-200-TC-Antenna-Cable-Analyzer-12-1-2015.htm"
...
"The Netherlands IARU member society
VERON has reported that hams there have an opportunity to reclaim
their [465]
QSL cards salvaged from the wreckage of Malaysian Airlines Flight
MH17, which was shot down over Ukraine in 2014 — provided they're willing to cover
the cost of having them cleaned. VERON spotted the recovered cards in a YouTube
video last year, and the Dutch QSL Bureau confirmed that a shipment of QSL cards
had been headed for Indonesia, the flight's planned destination
..."
Merriam-Webster defines
Christmastide as "the festival season from Christmas Eve till
after New Year's Day or especially in England till Epiphany." In 1930 when this
article appeared in Radio-Craft magazine, most likely everyone knew what Christmastide
was, but not so much today. While reading and scanning vintage magazine articles
throughout the year, I set aside ones specific to holidays like Christmas, Thanksgiving,
Halloween, etc., and post them during their respective seasons. This story is about
the trouble caused by a well-meaning but unqualified family member attempting to
fix a radio that wasn't broken by gifting dear old Dad a Balkite trickle charger
(radiomuseum.org has one) for his battery-powered
radio set. It also mentions using a potato to test the DC polarity of a power supply
or battery. Last but
...
Unmanned Systems of World Wars I and II
(Intelligent Robotics and Autonomous Agents series),
by H. R. Everett. While writing this book, Mr. Everett contacted me for information
I have on the
QL-17 drone by Temco for Army's Signal Corps Engineering Labs.
"Military drones have recently been hailed as a revolutionary new technology that
will forever change the conduct of war. And yet the United States and other countries
have been deploying such unmanned military systems for more than a century. Written
by a renowned authority in the field, this book documents the forgotten legacy of
these pioneering efforts, offering the first comprehensive historical and technical
accounting of unmanned air, land, sea, and underwater systems... A pioneering Navy
roboticist, Everett not only describes these systems in detail but also reverse-engineers
..."
Antenova-M2M-Lucida-Surface-Mount-Antenna-12-1-2015.htm" >
Antenova Ltd, manufacturer of antennas and RF
antenna modules for M2M and the Internet of Things, announces the arrival of
Lucida - an SMD antenna for all LTE applications, including
MIMO systems. The antenna is fully tested and ready to ship from now. The Lucida
antenna does just that, operating in all of the LTE and mobile bands: LTE 700, GSM
850, GSM 900, DCS 1800, PCS 1900, WCDMA 2100, LTE B7. This makes it suitable for
use in 4G MiFi routers, Femto/Pico base stations, portable devices, remote monitoring,
network devices, and wearable devices. Lucida is an Antenova-M2M-Lucida-Surface-Mount-Antenna-12-1-2015.htm"
...
Buried in a list published by the UK's Ofcom
(equivalent to USA's FCC) of potentially Wi-Fi offending
household devices and appliances is the innocuous
Fairy
Light - a product that has become very popular at Christmas in the last
few years. For some reason all the news media has glommed onto this tidbit to make
a big deal out of it. The aforementioned list was issued as part of a promotion
for Ofcom's new 'Wi-Fi Checker' smartphone app. A search for exactly why these
fairy lights might cause Wi-Fi signal degradation did not turn up any information
about how they might generate EMI. If there is a switching AC-DC converter somewhere
in ...
Notable Tech Quote: "QST" Again
"We have heard that some cats have seven
and others nine lives, but darned if we don't believe radio bugs have cats outclassed."
- Hiram Percy Maxim, in the April 1919 edition of QST magazine, commenting
in
"QST" Again (this is the actual
document), on the surge of requests for the publication to resume printing
after the amateur radio broadcasting ban was lifted once World War I ended.
Further, "As we think over the dreary two years of amateur deadness, it's a real
hard job to believe that any of us are still in existence
..."
Mr. Richard Song, a very friendly fellow I
knew when he worked for a different company, wrote to me recently saying he was
now the Marketing Director for South Korean RF and microwave product company
Withwave, Inc. Withwave's
offerings are similar to what he had been
working on, so the move was a natural transition.
Withwave's product line is primarily coaxial connectors, adapters, terminations,
attenuators, cable assemblies, and accessories for test applications. One item in
particular really interested me: the coaxial-to-planar
T-Probe™.
Per Withwave's website: "Withwave's T-Probe is coaxial probe that offers one signal
pin on center and several fixed pitch ground contact with low inductance. This probe
provides excellent electrical performance
..."
Saudi Arabia's
Jeddah Tower, already built up to the 26th of 200 floors for
a total height of World's tallest tower gets $1.2B to complete construction | Fox
News 3,280 feet (1,000 m), will replace the Burj Khalifa (2,716 ft | 828 m) as the
world's tallest building when complete in 2018. The record won't be held for long
if Iraq has its way, though. Basra Province is planning to build the 3,779 foot
(1,152 m) Bride
Tower with 230 stories topped by a 616 ft high antenna.
First prize in this circa 1936
reader-submitted design ideas went to William G. Scott for his
wind-powered battery recharger. It was a rather elaborate contraption made of surplus
lawn mower and automobile (Ford Model T, no less)
generator. There are two very good reasons why someone would find the need to build
his own battery charger in the era. First, good luck finding a commercial product
to do the job, and if you could, the cost would be prohibitive for most radio enthusiasts.
Second, prior to the Rural Electrification Act of 1936, most households not in or
near cities and towns had no commercial electric service. Electricity, if any, was
...
