See Page 1 |
2 |
3 |
4 | of the May 2020 homepage archives.
Friday 8
Anytime I see an airplane in a photograph,
my interest is immediately piqued to learn the story behind it - sort of like with
the "MPATI - Its Problems & Solutions" feature in the May 1963 edition of
Electronics World magazine. This "Aerial
'Private Eye' Traces TV Signals" story also involves airplanes and television
broadcasting, albeit in a completely different way. A couple enterprising broadcast
engineers created a company called Tele-Beam Industries, in Napa, California, that
measured and mapped TV signal strength in the region surrounding transmission towers
to provide the stations with information useful in marketing and radiation characteristic
planning. Signal strength measurements were made from some starting altitude down
to within 100 feet of the ground, in 100 foot increments, and was repeated in increments
of 10° of azimuth...
Depending on your point of view, this snow
on May 8th, here at RF Cafe headquarters in Erie, Pennsylvania, is a downright cool
or a downright scary phenomenon. I consider it cool, and is one of the reasons I
choose to live here. As a kid growing up in
Mayo, Maryland, where snow is not so common, I wished we had lived in the Buffalo,
New York, area where my father's side of the family was centered. Buffalo, as you
probably know, never wants for snow. Next week we'll probably turning on the air
conditioner for the first time this year, so for now I'll be glad to see the snow.
BTW, it's supposed to snow tomorrow morning as well.
"The imaging mode is called the
Virtual Rescanning Mode, or VRM, and can find small or oddly located anomalies
that may have caused the failure. When electronic components for critical applications
experience structural failure in service, it typically is worthwhile to collect
as much data as possible about the failures to reduce the risk of similar failures
in the future. The mechanism that caused a structural field failure might have occurred
suddenly, or might have been the result of gradual change. If the component itself
has largely survived, it may be imaged by ultrasound via an acoustic micro imaging
tool to view and analyze its current internal structure to help determine the cause
of the failure..."
Rohde & Schwarz is offering at no cost
a variety of
reference
charts (posters) for hanging on your lab or office wall - maybe enough to wallpaper
an entire cubicle, and some handy-dandy Pocket Guides. I just updated the page to
fix expired hyperlinks and add links to new posters. In the current age of (seemingly)
paperless offices and laboratories, opening a cardboard package from R&S containing
the pictured items caused me to wax nostalgic over the days when sales reps handed
out such materials during workplace meetings and at trade shows. Wall charts are
still fairly easily obtained, but the spiral-bound pocket guides are more rare.
Maybe soon we'll be seeing the resurrection of cardboard slide rule calculators...
RF Cafe's continued existence depends on
companies like ERZIA providing support. ERZIA produces
microwave and mm-wave modular amplifiers
and integrated assemblies operating from low frequencies up to 100 GHz. Their
catalogue of standard amplifier modules comprises more than 100 different models,
having also a high capacity of customization for amplifiers and integrated assemblies.
Some of products have space heritage and are used in aerospace, commercial, military
and scientific systems, having a wide range of final applications.
Z-Comm is proud to announce a new
dielectric resonator oscillator model
DRO12200A for radar system applications. The DRO12200A is designed to cover
12200 MHz while incorporating both electrical and mechanical elements for fine
and coarse tuning. This high performance DRO is optimized to feature superior low
phase noise of -105 dBc/Hz @ 10 kHz offset and operates off a 5 Vdc
supply while typically drawing only 23 mA of current. The DRO12200A is designed
to deliver a typical output power of 0 dBm into a 50 ohm load and is guaranteed
to operate over the industrial temperature range of -40 to 85°C. This remarkable
oscillator suppresses the second harmonic to better than -30 dBc and covers
the optimized frequency with a tuning voltage range of 0 to 12 Vdc while featuring
a tuning gain of 0.5 MHz/V...
In my daily routine of perusing the WWW (World
Wide Web - remember that?) for good information to post, I need to copy images into
which thumbnail versions are made. A very recent trend has evolved for the sake
of mobile device displays which appends some sizing directives to the end of the
otherwise normal URL, and that prevents doing a copy and paste with right-click
-> Copy Image, and then paste it into a graphics editor. Instead, do
a right-click -> Copy Image Location
and then paste that URL into your browser. Click the thumbnail image above for an
example. Note the appendage after the ".png" file extension:
?auto=format&fit=crop&h=432&w=76"
That prevents the normal Image Copy from working. Delete everything after .png and
then hit enter. You should now be able to copy and paste the image into your editor.
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.
Thursday 7
Around the time this article was written,
the first wave of the solar and wind (which essentially is also solar) power generation
craze was settling in. A few small windmill generators popped up around where I
lived in the Annapolis, Maryland area, but they were mostly owned by hippie Earth
worshipers who eschewed modern conveniences and didn't need hot water for bathing
anyway. Most of that generation (pun intended) of windmills put out direct current
(DC - typically 12 or 24 volts) rather than tying in with the AC line power, and
required separate electric wiring in the house. People used appliances and light
fixtures designed for recreational vehicles. We knew a very nice older man and his
wife who lived "off the grid" and grew most of their produce and even kept a goat
for milk (they were clean people). They had some
photovoltaic (PV) solar cells to supplement the windmill...
Microwaves & RF magazine just
posted the Employment portion of their "2019
Salary & Career Report." It might seem like last year's news and not relevant,
but the year has to be over in order to assimilate data from the entire year, so
it really is timely. Author James Morra wrote, "Most respondents said that they
feel confident about their prospects for employment. But many are also troubled
by the possible shortage of skilled engineers and its impact on the broader industry,
according to 750 respondents polled by Electronic Design and Machine Design last
year. Endeavor's Design Engineering and Sourcing group rolled out the survey with
questions on more than 40 separate topics, ranging from salaries to job satisfaction..."
"British Columbia radio amateur Scott Tilley,
VE7TIL, has found another 'zombie
satellite,' as he calls them. This time, he tracked and identified radio signals
from the experimental UHF military communication satellite LES-5. Tilley says he
found the satellite in what he called a geostationary 'graveyard' orbit after noting
a modulated carrier on 236.7487 MHz. 'Most zombie satellites are satellites that
are no longer under human control, or have failed to some degree,' Tilley told National
Public Radio (NPR) earlier this month. LES-5 was built by MIT's Lincoln Laboratory
and launched in 1967 as part of the military's Tactical Satellite Communication
Program. It was supposed to shut down in 1972, but it continues to operate as long
as its solar panels are facing the sun. Tilley told NPR that he was inspired by
a ham in Cornwall who, in 2016, found an earlier satellite - LES-1 - built by the
same lab and launched in 1965. What intrigued Tilley about LES-5 was that
it might be the oldest functioning geostationary satellite
in space..."
Innovative Power Products (IPP) has over
30 years of experience designing & manufacturing RF & microwave passive
components. Their high power, broadband couplers, combiners, resistors, baluns, terminations and attenuators
are fabricated using the latest materials and design tools available, resulting
in unrivaled product performance. Applications in military, medical, industrial
and commercial markets. Take a couple minutes to visit their website and see how
IPP can help you today.
John Dunn has a good article on the
EDN website entitled, "Understand
the Damaging Effects of Phase Dispersion." He begins: "Amplitude modulation,
or AM, is probably the simplest method of getting a voice or some music onto a radio
signal and then sending that signal off to some far distant place. Because of that
simplicity, a study of AM signals is a convenient tool for showing a damaging effect
arising from phase dispersion. With AM radio, the audio signal usually gets reproduced
pretty nicely at the receiving end, but not always. Sometimes a phrase like, 'You
give us 22 minutes and we'll give you the news' can come out sounding like 'Y'mph
gvmmph ush tentee-two mnshunts...' and maybe you would wonder why. Consider an AM
signal source from which there is a carrier that, just for the sake of example,
we can amplitude modulate using either the first or the second of two 'audio' signals..."
If you didn't know better, you might conclude
from my writings that I detest
CFL bulbs.
I really don't. In fact, I rather like them for most applications. My house was
full of them until the LED bulbs began to replace them, but the LEDs are not much
better in terms of complexity. At least they do not contain mercury. What I detest
is a world of bureaucrats that have determined that Edison's paradigm-changing incandescent
light bulb is such an evil device that they have conspired to ban it off the face
of the Earth. Based largely on fallacious, contrived "scientific" data about anthropogenic
(human-caused) global warming, the wizards of smart declared that the incandescent
bulb is singularly responsible for hurricanes, species migration and extinction,
disease, and crop failure. It simply must go. All praise be to the United Nations
heads of state and to lawmakers on Capitol Hill for caring so much about little
'ol us. Can I have an "amen!" Ever eager to please, but certainly in nowise complicit,
industry chieftains have fallen in line and produced that which will appease our
self-appointed Earth Sentinels: the compact fluorescent light bulb...
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.
Wednesday 6
Phased
vertical stacks of two or more antennas were fairly common in the television
realm - especially once color broadcasts became more dominant in the 1950s. Up to
3 dB per additional antenna is possible, but due to various non-ideal physical
parameters (summed phase angle, imperfect antenna geometry, etc.), realized gain
is typically in the 2.5 to 2.8 dB range. Higher signal to noise ratios were
needed to guarantee good color separation with the National Television System Committee
(NTSC) and stereo channel audio separation with the advent of Multichannel Television
Sound (MTS). As you might expect, companies appeared claiming to have invented physics-defying
antennas that "outperform all present antennas." This particular "Super 60"
model from All Channel Antenna Corporation further claims to outperform antennas
that use a mechanical rotator (see my Alliance U-100 Tenna-Rotor) by virtue of its
9-position electronic phase switching...
"A GPS receiver just isn't going to cut it
in deep space. While GPS has a host of applications on Earth - from enabling credit
card transactions to weather forecasting - it is decidedly less useful off planet.
After all, GPS was designed to enable navigation around the Earth, not in deep space.
Space vehicles operating beyond the reaches of GPS have to rely on other methods
for determining their position, navigation and timing, such as inertial measurements
or even star tracking. Those methods vary in reliability, so the Department of Defense
is looking for a more accurate tool - namely, a
quantum space sensor. The Defense Innovation Unit - the organization within
the DoD charged with leveraging commercial technologies for military use - is seeking
a compact, high-performance sensor that can use quantum technology to provide precise
inertial measurements in deep space..."
RF Cafe typically receives 8,000-15,000
website visits each weekday and about half that on weekends.
RF Cafe is a favorite of engineers, technicians, hobbyists, and students all
over the world. With more than 13,000 pages in the Google search index,
RF Cafe returns in favorable
positions on many types of key searches, both for text and images. New content
is added on a daily basis, which keeps the major search engines interested enough
to spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. If you need your company news to be seen, RF Cafe is the
place to be. Advertising begins at $40/month.
Exodus Advanced Communications is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Power amplifiers ranging
from 10 kHz to 51 GHz with various output power levels and noise figure
ranges, we fully support custom designs and manufacturing requirements for both
small and large volume levels. decades of combined experience in the RF field for
numerous applications including military jamming, communications, radar, EMI/EMC
and various commercial projects with all designing and manufacturing of our HPA,
MPA, and LNA products in-house.
When
deficits are already in the multiple T's, money is no object for government entities,
including the cost of changing the logo on all printed communications. Note how
red (Rep) is missing from America's traditional rw&b colors in the new design.
"In anticipation of its upcoming move, the FCC has
adopted a new FCC seal. The redesigned seal is the product of an agency-wide
contest that solicited proposals from employees and contractors. The winning design,
submitted by Umasankar Arumugam, was selected by a vote of the agency's employees
and contractors. The revised design incorporates several elements: communications
technologies currently transforming our world. Over the next few months, the FCC
will incorporate the new seal on official stationery, business cards, publications,
and other materials, including on its website and throughout its new Headquarters.
Official use of the new seal will begin following completion of the agency's move
from the Portals to its new Headquarters..."
Copper Mountain Technologies' (CMT) RNVNA
solution is a customizable multiport network analysis solution for MIMO antennas
and other 5G applications.
RNVNA builds on the capabilities of CMT 1-Port USB vector network analyzers.
RNVNA links up to 16 analyzers together into a multiport network analysis system,
allowing users to measure vector reflection and scalar transmission parameters.
RNVNA is compatible with all Copper Mountain Technologies' 1-Port USB VNAs with
frequency ranges up to 6 GHz (R60), 14 GHz (R140), and 18 GHz (R180).
RNVNA software allows users to manage multiple 1-Port VNAs performing required measurements.
A free demo version of the RNVNA software for systems using up to three 1-Port VNAs
can be downloaded...
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.
"On the
way back to your home state, don't let the door hit ya' where the good Lord split
ya'. Oh, and we'll be sending you a tax bill in appreciation for your selfless sacrifice
in caring for our citizens." That is basically the sentiment of New York's governor,
who after literally begging
out-of-state healthcare workers to come to NY City amongst the Chinese COVID-19
breakout, has declared that his financially mismanaged and cash-strapped state
is going to collect income tax from the aforementioned good Samaritans.
Tuesday 5
Hugo Gernsback is not necessarily a household
name in 2020, but in the early to middle 20th century, he was fairly well known
in both the hard science and science fiction realms. He was a prolific author of
books and magazines in both areas, applying his profound knowledge of technology
and his ability to foretell the futures of many aspects of communications, mechanics,
electronics, and marketing and societal behavior to the aforementioned. If you are
a regular RF Cafe visitor, you have seen very many articles written by Hugo Gernsback
reproduced. This particular work of prognostication appeared in a 1947 issue of
his Radio-Craft magazine. It presciently claimed that a post-war boom in
consumer buying after half a decade of sacrifice of creature comforts for the good
of the country and world would feed a significant adoption of
FM radio
over...
"Iowa State University computer engineers
have created an algorithm that could help to improve digital communications. This
algorithm, when combined with a closed-form solution, takes one of the most commonly
used algorithms and unlocks its hidden potential. The algorithm is actually part
of two, which are known as the
fast Fourier transform (FFT) and the inverse fast Fourier transform (IFFT).
These algorithms have been commonly used since way back in 1965; in the modern world,
they are responsible for analyzing the signal from a cell tower or base station
and synthesizing the signal from your phone to the base station, respectively. There
is already a generalized version of the FFT that is more useful and has been since
1969. This was known as the chirp z-transform (CZT)..."
ConductRF LSA series of
Low Loss, Performance flexible RF Cable Assemblies, provide microwave system
designers with a versatile solution for most applications. Offered is a solution
for 0.086" diameter cable that facilitates greater flexibility and handling or,
0.141" diameter that exploits the same great performance but with almost half the
loss. Connector options include SMA, Type-N, TNC & SMP that provide excellent
VSWR between DC and 18GHz, also solutions for MCX & SMB are available in a wide
array of configurations. These assemblies are built using our own double shielded,
FEP jacketed cable, that was developed specifically for performance solutions. With
shielding effectiveness exceeding 90 dB through 18 GHz...
Dig this: A 2003 episode of "Dead Zone" entitled
"The
Plague" could serve as a contemporary documentary of the whole COVID-19 pandemic,
but our official response is much different. It will probably be taken down from
YouTube soon, but this 3½ minute compilation of scenes include all the buzz
terms of today's scenario, including originating in China, coronavirus, mandatory
lockdown, quarantine, and guess what? Chloroquine, identified there as a malaria
drug, was the miracle cure. Have you noted how His Imminence
Dr. Fauci steadfastly
refuses to recognize the excellent and safe history of hydroxychloroquine? Its multi-decade
efficacy in treating viruses is well-documented, but the world is on forced lockdown
and economies being destroyed while awaiting a new drug with no long-term history.
In the mean time, many people suffer and/or die needlessly.
RF
Cafe visitor Joseph B., N3TTE, sent me a photo of a mystery device he obtained
along with "a box of ancient circuit boards that included a mess of parts." Says,
he, "One of the more curious things in the box is a small metal cylinder; 5/8" in
diameter, 7/8" high." It has 9 pins. Markings are shown in the photo. We have both
done an extensive, yet unsuccessful, search for a datasheet. Available info indicates
it is made by Vactec (eventually PerkinElmer and now
Excelitas) and is likely
a form of resistive optoisolator (RO, aka light dependent
resistor LDR). They were
used in a lot of audio equipment. If you know anything useful about this device,
please send me an e-mail and I will forward it to Joseph. Thanks!
Much more than just a self-serving video
of my new R/C airplane flight agility, this model represents a plethora of modern
electronics. Although the radio control system in this plane is a standard narrow
band FM variety on 72.170 MHz (as opposed to my 2.4 GHz, spread spectrum
system), the motor is a state-of-the-art 3-phase brushless model (E-flite 450)with
a sensorless electronic
speed control (E-flite EFLA331, 20 A). Power for both the radio and the
motor is supplied by a 3-cell (11.1 V) lithium polymer (Li-Po) battery rated
at 2,100 mAh with a 15C discharge current capacity. There was a time not so
long ago when no one though that electric power could ever provide a equivalent
to the nitro methane gulping internal combustion engines, but the time has come.
This all-electric setup is fairly small in size, but there are much larger motors...
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.
Monday 4
We take a lot for granted these days with
the seemingly unlimited availability of cheap stuff of all kinds - some of it complete
junk and other of it pretty darn good. That goes for electronics components and
complete products and test equipment, tools, automobiles, appliances, and utensils,
clothing, medical equipment - you name it. Something as simple as a
pistol-type soldering gun can be purchased at just about any hardware or home
store, and at a price that when adjusted back to equivalent money in the 1940s would
be amazingly cheap even then. For instance a Weller Soldering Gun kit from Lowes
sells for $39.48 today (less when on sale), which would have been $3.44 (per the
BLS Inflation Calculator) in 1947 when this article showing how to build your own
appeared in Radio-Craft magazine. If a soldering gun could have been purchased
for a mere $3.44 in 1947, there would have been no need to publish such an article
because its cheapness would have obviated...
Exodus Advanced Communications' model Exodus
AMP2041-1 "Beast" is 1.0-2.5 GHz class A/AB solid state power amplifier
(SSPA), rack-mounted system with a rated output power of, 2200 watt minimum
(2.5 kW CW typical). It features a 1600 watt P1dB GCP with a minimum 63 dB
of gain. Built-in protection circuits, and forward & reflected RF sample ports
provided. Type N Female RF Input/Sample port connectors and a 1 5/8" RF output
connector are standard. Rack mountable drawers are housed in a 32U tall cabinet
including a power supply, cooling fans, and a controller for ease of use. Suitable
for applications requiring high power and broadband coverage for EW/ECM, as well
as general EMC testing in labs, chambers or application requiring high RF field
levels.
"The Space Development Agency plans to award
contracts for a mesh network in space this August, with the expectation that an
initial batch of
20 satellites will be placed on orbit during summer 2022. The agency expects
to release a request for proposals for the contracts May 1. The announcement came
during an industry day the agency hosted over the phone April 2. The industry day
was originally slated to take place during the 36th Space Symposium in Colorado
Springs April 2, however, after that event was cancelled due to the circumstances
with COVID-19 the agency opted to hold a virtual industry day instead. According
to SDA Director Derek Tournear, 580 people called in for the event. That first batch
will include 20 satellites and will comprise what Pentagon leaders are calling Tranche
0 of the SDA's Transport Layer, a mesh network of satellites operating primarily
in low earth orbit..."
Have you heard about this? I hadn't. If you
think the only goal in Afghanistan is to stamp out the Taliban, think again. An
article in the October 2011 issue of Scientific American details the extensive
mineral surveys that have been carried out there in the last year or so. Afghanistan
is home to what may be the largest cache of
rare earth elements
in the world, with a potential to replace China as the largest extractor (~90%)
of those atoms that lie in the lanthanide and actinide regions of the periodic table
- the two rows that are typically pulled out of the chart. China, you may have heard,
is severely restricting the export of rare earths - wanting to keep it for themselves
- thereby triggering a near panic. Prices are rising so alarmingly that reopening
mines in the U.S. has once again become profitable in spite of the crippling regulations
that years ago closed down operations here (huge loss of jobs and tax revenue) and
forced us to become reliant on offshore supplies...
The
IMS2020 and Microwave Week, scheduled for 21-26 June 2020 in Los Angeles, CA,
USA, is transitioning to a virtual event. The 2020 organizers have made this difficult
decision after careful consultation and review with government authorities, partners,
and venues. The timeframe for the virtual event will be August 2020. IMS2020 is
the flagship conference of Microwave Week, the world's largest event for RF and
Microwave technology which brings 10,000 attendees from 48 countries and over 600
exhibiting companies. The virtual event will continue with the theme of "Connectivity
Matters," built on five pillars that link the world: 5G & 6G networks, aerospace
and defense programs, autonomous vehicles, the digital economy, and ensuring the
connection of under-represented communities. "The RF and Microwave industry is critical
in a time when we are striving to connect in a socially distanced world," said Timothy
Lee, IMS2020 General Chair...
Res-Net Microwave has a complete line of precision
RF & microwave components
including attenuators, terminations, resistors, and diode detectors for commercial,
military, and space applications. Products range from the small flange type to large
2,000 watt connectorized power attenuators and/or terminations at frequencies up
to 26.5 GHz. In-house photo etch and laser trim capability. The company is
a leader in development and production of the films required for these type of RF/microwave
components. Please check out Res-Net Microwave's website to see how they can help
with your current project.
Monday 4
As with my hundreds of previous
engineering and science-themed crossword puzzles, this one for May 3, 2020,
contains only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc., which I have built up over nearly two decades. Many
new words and company names have been added that had not even been created when
I started in the year 2002. 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, if you don't already know, might
surprise you.
E-flite's Blade CP radio controlled electric
helicopter comes from the factory with a 4-in-1 electronics unit that contains a
6-channel receiver that performs the functions needed for motor control, piezoelectric
gyroscope, BEC (battery eliminator circuit), and ESC (electronics speed control).
It also includes a dual-gimbal transmitter with an idle-up switch for transitioning
to aerobatic mode where both positive and negative pitch can be commanded to the
rotor head. My Blade CP has always flown well, but from the very beginning it has
been prone to sudden, uncommanded control movements (glitches). The results have
varied from slight jerkiness in the flight to a sudden high speed climb-outs (really
bad when inside).
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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