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.
Amateur Radio Astronomy
in QST Magazine
QST
is the official publication of the Amateur Radio Relay League (ARRL),
the world's oldest and largest organization for Ham radio enthusiasts.
Many amateur radio operators also have an interest in astronomy
and as such, occasionally articles appear covering topics on
amateur radio astronomy. There are also quite a few articles
dealing indirectly with aspects of astronomy such as Earth-Moon-Earth
(EME) communications where signals are bounced off the moon's surface
in order to facilitate transmission (although it is really more
of a hobby achievement). The October 2012 edition of QST had an
article entitled, "Those Mysterious Signals*," which discusses galactic
noise in the 10-meter band. Arch Doty (W7ACD) writes about the low-level
background noise that is persistent in the high frequency (HF) bands.
At HF, Cygnus A and Cassiopeia A are major sources of
cosmic noise, for example. Low level signals come from pulsars...
High Frequency Electronics
Articles Update
The
November edition of HFE is now online for the non-tree-killers and/or
the technophile-cum-e-reader types amongst us.
•
Wireless Sensors without Batteries, byAli Abedi
•
Benefits of Mixed Dielectrics When Used for High-Frequency PCB Applications,
by John Coonrod
Pasternack Expands Line of
High Power Attenuators
Pasternack
Enterprises introduces their new line of 100 Watt
high power attenuators. This new line of attenuators is perfect
for applications requiring reliable and consistent frequency levels
up to 6 GHz. Pasternack Enterprises’ line of
high power RF attenuators operate from DC to 6 GHz and
have an average power rating of 100 Watts, with peak power
handling capabilities of 2,000 Watts from -55 to +125°
C. High power fixed attenuators from Pasternack are constructed
with lightweight, but strong anodized aluminum heatsink bodies and
can be ordered with passivated stainless steel SMA, TNC and N connectors,
and silver plated brass 7/16 DIN connectors. Pasternack's high power
coax attenuators are manufactured with large cooling fins.
Sherlock Ohms: Strange
Case of the High
VSWRs
Sherlock
Ohms is a regular feature of Design News that presents submissions
from readers about troubleshooting challenges and how they were
solved. This one is titled "Strange
Case of the High VSWRs" The author discovers test equipment
setup issues.
Triad RF GaAs RF PA Module
Meets LTE Requirements
Triad
RF Systems introduced the
Model TA1011, a compact GaAs RF power amplifier module that
delivers over 20 W peak power from 1700 to 2000 MHz (other
bands available) and is well suited for both wireless communications
and CW applications including radar, electronic warfare, medical,
and measurement systems. The
TA10111 incorporates linear circuits that raise the OIP3 to
+60 dBm which allows this small amplifier to produce over 4 Watts
of linear, 10 MHz LTE. It has gain of 50 dB, return loss
of -14 dB (1.5:1 VSWR), rise and fall times of less than
1 µs, accepts a maximum RF input of +10 dBm and has a
30 dB RF Sample Port.
PMI Intros 1.0 to 26.5 GHz
Ultrabroadband
Amplifier
PMI
Model No.
PEC-14-127-8-12-SFF-1 is an ultra-broadband amplifier that operates
over the frequency range of 1.0 to 26.5 GHz. This model provides
gain of 13 to 17 dB and has a maximum gain flatness of ±1.5 dB.
The maximum noise figure is 5.5 dB from 1.0 to 20.0 GHZ
and 6.0dB from 20.0 to 26.5GHz. This amplifier can handle input
power levels up to +10 dBm with no damage and the Input IP3
is +3 dBm minimum.
Hytron Corporation Ad from
the June 1944
QST
Here
is an advertisement for
Hytron Corporation that I scanned from page 83 of my copy of
the June 1944 QST magazine. Hytron was a manufacturer of
electron tubes. "So Many Owe So Much To So Few," reds the title
line. That is a paraphrase of Winston Churchill's famous statement
during World War II, "Never
in the field of human conflict was so much owed by so many to so
few." That was in August 21, 1940, more than a year before the
U.S. entered the war. Perhaps of greater interest to RF Cafe visitors
are the next lines: "In peace, the Nation's debt to the radio amateur
was great. During hurricanes, floods, and other disasters, he sprang
forward with emergency communications. His endless hours of patient
experimentations - particularly on the high and ultrahigh
frequencies - helped open up, as if by magic, whole new segments
of the radio spectrum. Traffic enthusiasts surprised the people
with unselfish service; DX hounds fostered international goodwill."
Webinar: Antenna Simulation
with COMSOL
Multiphysics
Introduction
to Antenna Simulation with COMSOL Multiphysics, Thursday, November
29, 2 PM ET. The COMSOL Multiphysics RF Module is well-suited for
the modeling of antennas. In this webinar, a classical dipole antenna
model will be built and solved from scratch. All of the key steps
in the software will be addressed. More complex models will be introduced,
and applicability in Multiphysics areas such as RF and tissue heating,
as well as thermal drift and deformation modeling will be discussed.
Mayfield Plastics Releases
Thermoforming
Whitepaper
Mayfield
Plastics has announced the release the “Introduction
to Thermoforming and Vacuum Forming Whitepaper”. Mayfield constructed
the guide because they realize that many people, including designers
and engineers, do not completely understand the plastic forming
process. Often confused with injection molding and rotational-molding,
thermoforming processes are unique and have distinct differences
for a variety of applications. Thermoforming produces
custom plastic enclosures that are durable, cost-effective,
high quality and aesthetically appealing while offering close tolerances,
tight specifications and sharp detail.
AWR’s Schedule of Activities
at MWE 2012
AWR
is offering an array of software demonstrations, lectures, and partner
presentations at the
Microwave
Workshops and Exhibition 2012 (MWE2012) in Yokohama, Japan from
November 28 through November 30.
AWR’s booth #A305 featured demonstrations of the AWR Design
Environment include: Analyst for 3D EM analysis, Power amplifier
design using digital predistortion for linearity improvement, High
performance circuit envelope simulation ,Radar system simulation
using Visual System Simulator™ (VSS) and comprehensive radar libraries,
Antenna design using AXIEM®, Microwave Office™/AXIEM for PCB verification
via ODB++, Matching circuit synthesis using iMatch and filer synthesis
using iFilter.
Does America Have
a Scientist
Shortage?
Not
according to
Derek
Lowe (aka 'The Contrarian').
In his October 2012 article that appeared in
Discover
magazine, Mr. Lowe cites the following statistics to support his
assertion: Of 633e3 graduate-level students in science, engineering,
and health fields in 2012, less than ¼ secure a tenure track
academic job within 5 years of earning a Ph.D. Of 63e3 postdoc appointees
in the same group, up 45% from 2000, many cannot find permanent
employment. A 3% (doesn't seem like that
much to me) decrease from 2006 to 2010 in federal non-defense
R&D funding harms science-related
job seekers.
The overarching theme is that the problem is not a deficit of graduates,
but a glut of high quality candidates for employers. He also published
an article on the same topic earlier in the year titled, ".No,
America Does NOT Need More Scientists and Engineers" It's a
thing with him.
Thanks to Copper Mountain
Technologies for
Support!
Copper
Mountain Technologies is changing the way Vector Network Analyzers
are incorporated in lab and production environments. The company’s
unique virtual VNAs deliver highly accurate measurements at half
the cost of traditional VNAs. Leveraging breakthrough advances in
RF technology, CMT’s Planar VNAs provide high measurement accuracy,
a wide dynamic range, a familiar UI and a broad variety of standard
features. By developing VNAs that utilize external PCs, CMT offers
users flexibility, portability, improved security and upgradeability.
U.S. Department of State Says
Spacesuits
Are Weapons
Who
would have guessed that you need the blessing of the U.S. Department
of State if you want to make and sell spacesuits? Yep, spacesuits
are classified as weapons since, by
bureaucratic logic (yeah, a non sequitur),
if you have the capability to attain a presence at an altitude that
requires a spacesuit, you can be a strategic threat to the nation.
Here is a story about a startup company in Brooklyn, NY, that found
out the hard way about the
spacesuit-weapon requirement. There is a rapidly growing demand
for functional-yet-stylish spacesuits for safeguarding wealthy space
tourists who will soon be blasting off to the top of Earth's atmosphere
where space officially begins (at about
50 miles / 80 km). BTW, I tried finding the official
policy on spacesuit production the
Department of State
website, but their search engine keeps failing - must be busy deleting
files on the
Benghazi massacre.
More November 2012 Magazine
Articles Available
Some
of the RF & microwave magazines have updated their online editions
for November, so here are a few you might like to check out. A lot
of the articles end up being way over my head in theoretical applications,
so I tend to stick with practical stuff that most of us can use.
You be your own judge, though.
•
Emerging RF Technologies for Smartphones and Connected Devices,
by Ben Thomas, RFMD
•
Why Test Instrument Frequency Range Matters When Conducting Signal
Integrity Measurements, by Bob Buxton
•
Just Under the Radar: Where Does It Go From Here?
Bob Pinato,
MPD Editorial Advisor
•
Spectrum Analyzers Continue to Advance, by
Frost & Sullivan
Delco Radio Advertisement
from the June
1944 QST
Here
is an advertisement for
Delco Radio that I scanned from page 77 of my copy of the June
1944 QST magazine. "What's Magic About Electrons?," is
the question asked. Answer: "The magic about electrons is man's
ingenuity in putting them to work. The magic about electrons is
their promise of service in marvelous ways only hinted at in the
last few years. Now harnessed for war, the science of electrons
will later work to enrich the peace. Working in close cooperation
with Army and Navy engineers, Delco Radio has applied its knowledge
and skill in putting electronics actively and effectively into the
fight for Victory. In Delco's laboratories, principles are explored
and exploited; in Delco's engineering departments, designs are evolved
to apply these principles; and on Delco's production line, complete
equipment is manufactured with the speed and skill that only
a large manufacturer of precision radio instruments can bring to
such work."
They Know Where You Are...
and What You
Want
The
December 2012 edition of
Scientific American has a short article discussing how much
information not just Big Bro but also the Internet search engines
has on you - both from a historical perspective and in real time.
In the former case the purpose is for
surveillance
and exploitation for a blackmail motive if the need arises, and
in the later case for exploitation with a profit motive since the
need always arises. Your cellphone is a godsend to such amassers
of personal data. As reported, services like
PlaceIQ*
and Skyhook†
know that you are most likely to click on a smartphone advertisement
if, based on your phone's location data, they discover you are sitting
in a movie theater before the film starts rolling, if you are at
home on a Sunday morning, or if you are in the middle of a lake
fishing. That is when the ad services charge companies the highest
fees for serving a clickable promo to your phone. With enough data,
they can deduce your personal identity. Maybe that can be used to
set up an ambush by a hacker who gets access to it. Nice, eh? You
are soooo... predictable!
* Per their website, "PlaceIQ extracts
context and meaning from location data and organizes this into actionable
intelligence about a hyper local location."
† - “There's
no part of society that's not going to use these data,” says Ted
Morgan, CEO of Skyhook
Experts Face Fewer
Challenges in Court
Expert
witnesses play a big role in most - if not all - of the court cases
that get reported here on RF Cafe.
IMS ExpertServices is a law firm specializing in expert witnesses.
Every month or so they send me an article about specific court cases
that could be of interest to my visitors. This particular installment
is titled, "Experts
Face Fewer Challenges in Court, Survey Says" and reports that
after a decade of increases, in the year 2011 a large drop in the
numbers of court challenges to expert witnesses' testimony has been
observed. Surprisingly, nearly half of the experts' opinions were
successfully challenged. The leading reason for dismissing expert
testimony: lack of reliability. Who would've guessed that a person
getting paid to advocate a point of view might not be the most credible
client.
PMI Intros 5.3 to 6.0 GHz
Quadrature Coupler
PMI
Model No.
QC-5D3G6G is a quadrature coupler that operates over the frequency
range of 5.3 to 6.0 GHz. This model provides low loss of 1 dB
and an isolation of 18 dB minimum. The VSWR is 1.4:1 maximum
into a 50 ohm impedance. The amplitude balance is ±0.7 dB
maximum and the phase balance is ±5 degrees maximum.
Sherlock Ohms: Lightning
Knocks Out Aircraft
Compass
Sherlock
Ohms is a regular feature of Design News that presents submissions
from readers about troubleshooting challenges and how they were
solved. This one is titled "Lightning
Knocks out Aircraft Compass." Lots of people have magnetization
stories to tell, evidently.
Thanks for Pulsar Microwaves'
Continued
Support
Pulsar
Microwave is celebrating its 25th anniversary as a valued supplier
of passive microwave components covering the frequency range of
10 kHz to 40 GHz with both narrow band and ultra-broadband products
for the wireless communications markets. ISO and RoHS.
PMI Intros 1.4 to 2.4 GHz LNA
PMI
Model No.
PE2-42-2G-2R0-15-SFF is a low-noise amplifier that operates
over the frequency range of 1.4 to 2.4 GHz. This model provides
gain of 42 dB minimum with a typical noise figure of 1.8 dB.
The output power at 1 dB gain compression is +22 dBm typical
and the output IP3 is +30 dBm typical. This amplifier is supplied
in our standard PE2 housing that can be used with SMA connectors
or as surface mount.
Science & Engineering Theme
Crossword
for 11/25/2012
For
the sake of avid cruciverbalists, each week I create a new
crossword puzzle that has a theme related to engineering, mathematics,
chemistry, physics, and other technical words. You will never be
asked the name of a movie star unless he/she was involved in a technical
endeavor (e.g., Hedy Lamar).
Thanks to ISOTEC for
Long-Time Support
Since
our inception in 1996 in Korea, ISOTEC has been a leading manufacturer
of custom designed RF and Microwave Filters and sub-system products
for wireless service providers. We provide recognized and trusted
products and service to our customers in more than 30 countries
worldwide. ISOTEC offers an extensive product mix with filters and
Multiplexers that satisfy requirements from 100 kHz to 20 GHz.
RF Connectors and cable assemblies are also present in our product
portfolio.
ESD Basics: From
Semiconductor Mfg to Use
ESD
Basics: From Semiconductor Manufacturing to Use, Steven H. Voldman
(he was my Semiconductors class professor
for two semesters at UVM) The text is unique in covering
semiconductor chip manufacturing issues, ESD semiconductor chip
design, and system problems confronted today as well as the future
of ESD phenomena and nano-technology. Extensive coverage on the
fundamentals of electrostatics, triboelectric charging, and how
they relate to present day manufacturing environments of micro-electronics
to nano-technology, semiconductor manufacturing handling and auditing
processing to avoid ESD failures ESD, EOS, EMI, EMC, and latchup,
component and system level testing to demonstrate product resilience
from human body model (HBM), transmission line pulse (TLP), charged
device model (CDM), human metal model (HMM), cable discharge events
(CDE), to system level IEC 61000-4-2 tests, and ESD on-chip design
and process manufacturing practices.
Happy Thanksgiving!
Please Thank Dong Jin
Technology for Their
Support
Dong
Jin Technology Innovations designs, manufactures, and assembles
RF connectors,
cable assemblies, arresters, attenuators,
adaptors, bias Tees, filters, terminations, directional couplers,
power combiners, power dividers. Competitive price, on-time delivery
and best quality. No minimum order size. One-day delivery.
Job Hunting Resources
IEEE's
Job Site Alerts are mailed out periodically with a handful or so
of job hunting tips.
•
The 10 Non-California Tech Companies You Wish You Worked For
(note: 37 Signals' Jason Fried writes
a great monthly column in
Inc magazine)
•
Are You Ready for the Phone Interview?
•
Burgeoning Microelectronics Sector Expects Jobs Growth
IEEE-USA Government Fellowships
Linking
Science, Technology & Engineering Professionals with Government
Each year, IEEE-USA
sponsors government fellowships for three qualified IEEE members. The
fellows — chosen by the
IEEE-USA Government Fellows Committee and confirmed by
the Board — spend a year in Washington serving as advisers to
the U.S. Congress and to key
U.S. Department of State
decision-makers. Known as either a Congressional Fellowship
or an Engineering & Diplomacy Fellowship, this program links
science, technology and engineering professionals with government,
and provides a mechanism for IEEE's U.S. members to learn firsthand
about the public policy process while imparting their knowledge
and experience to policymakers.
The Secret to Eliminating ESD
Damage? Read
Your Datasheet
ESD
is a big potential [pun intended] problem for modern electronics.
Ultra small gate thicknesses and overall geometry miniaturization
of ICs makes for vulnerability to shocks. All new IC designs incorporate
some level of
ESD protection, but discrete devices like transistors often
do not. Low voltage electronics that operate off of just a couple
volts are using super small capacitors and resistors that are only
rated for 6.3 V. Improperly designed circuits can easily be
taken out when you grab your cellphone or iPod on a cold, arid day.
Design News' Charles Murray has sage advice for dodging such hazards:
Read your datasheet. I would also suggest also researching the
plethora of papers and books written on the subject.
FQXi: Is Reality Digital
or Analog?
Each
year the Foundational Questions Institute (FQXi)
holds an essay contest inviting writers to submit missives addressing
the question chosen by the FQXi board as being particularly thought-provoking.
In their words, "FQXi catalyzes, supports, and disseminates research
on questions at the foundations of physics and cosmology, particularly
new frontiers and innovative ideas integral to a deep understanding
of reality, but unlikely to be supported by conventional funding
sources." The 2011 question was "Is Reality Digital or Analog?"
Scientific American magazine, being one of three partners,
published the runner-up entry in the December 2012 issue: University
of Cambridge professor of theoretical physics professor David Tong's
paper argues that the world is in fact fundamentally analog. Professor
Tong actually tied for second place, but for some reason SciAm does
not tell us whether the other second place paper supported an analog
or digital viewpoint. For that matter, it did not say which side
the winning paper came down on. Strange. I looked it up on the FQXi
website. First place went to Jarmo Makela, who believes reality
is digital in nature based on a personal discussion with Isaac Newton
in his London home in the year 1700. When...
Hams on the Alaska Highway
Even
though my fingers stop working when exposed to temperatures below
freezing, I love the northern climate - four full seasons, snow,
iced-over lakes, migrating birds, fiery autumns, cool summers, the
whole experience. Having the option of not participating in the
cold outdoor environs is what makes it good. However, the
U.S. Army Signal Corps guys pulling duty in Alaska during World
War II did not have that luxury. As told by radio engineer
Major Colvin in this story from a 1945 edition of ARRL's QST magazine,
winter life in Alaska at -40° was a real challenge. It was a
world where Prestone antifreeze froze, the sun shone only a few
hours a day, vehicles had to be left running 24/7 or risk not being
able to be re-started, and mile-long treks between buildings was
common. There were no snowmobiles. The success of the communications
station was attributed to "the high percentage of amateur radio
operators and technicians."
Pasternack Intros New Line
of HF PIN Diode
RF Switches
Pasternack
Enterprises introduces their new line of high frequency
RF switches. These high isolation RF switches have frequency
ranges from 500 MHz to 40 GHz and a power rating of 0.1 Watts
(+20 dBm).
Please Welcome Advertiser
Venture Technologies!
Venture
Technologies designs and develops innovative wireless products
that measure, analyze and control. RFOS - a customizable, modular
wireless platform - results in better products that cost less to
develop. The cost and performance of full custom with the ease of
a module. An in-house developed customizable, modular wireless platform,
RFOS™, allows better, faster development with lower NRE costs.
Core embedded wireless capability is wrapped in full service "spec
to production" product development.
China to Build World's Tallest
Skyscraper
in 90 Days!
China's
about to do it again. The country that two millennia ago built the
Great
Wall has awoken from a long slumber to, beginning two decades
ago, accomplish a long string of world-record-breaking projects.
What used to be the domain of
American and Western ingenuity is now the realm of Chinese engineers
and craftsmen. Of course much of the capability originated in Western
schools and corporations, but the Chinese people have proven to
be quick learners and motivated, highly capable creators. While
America is in the process of destroying personal freedoms and demonizing
hard work, academic excellence, and capitalism, China is doing just
the opposite. Our leaders are pathetic one-world weaklings while
theirs are strong and nationalistic. The result is obvious to all
with eyes open. China's latest feat will be to build the world's
tallest skyscraper in just 90 days!. "Sky
City One" (aka J220) as planned is 2,750 feet tall and will
beat Dubai's
Burj Khalifa
by 33 feet at half the cost. Nearly 95% of the structure will use
prefab sections to create 10.8e6 square feet of office space on
220 floors, all connected by 104 elevators. It will be complete
by the end of this coming winter - compliments of WalMart shoppers.
Viel Dank to Reactel for
Continued Support
Reactel
designs and manufactures RF and microwave filters, diplexers,
and subassemblies, DC-50 GHz. Suspended substrate, LC,
ceramic, tubular, miniature cavity, waveguide, switched filter banks,
combline, interdigital. Contact them with your specifications.