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5 of the September 2020
homepage archives.
Berkeley Nucleonics Corporation (BNC)is a leading manufacturer of precision electronic
instrumentation for test, measurement, and nuclear research. Founded in 1963, BNC
initially developed custom pulse generators. We became known for meeting the most
stringent requirements for high precision and stability, and for producing instruments
of unsurpassed reliability and performance. We continue to maintain a leadership
position as a developer of custom pulse, signal, light, and function generators.
Our designs incorporate the latest innovations in software and hardware engineering,
surface mount production, and automated testing procedures.
As evidenced by this advertisement in a circa
1951 issue of Radio & Television News magazine,
Channel Master has been producing commercial broadcast television
and radio antennas and antenna accessories for a really long time. They are one
of the very few companies still making such items, with RCA being another. A few
years ago I bought a high gain Channel Master VHF-UHF-FM antenna for use with my
vintage Alliance Model U-100 Tenna-Rotor. Both companies still sell remote control
(wired) antenna rotators. Being an ardent over-the-air broadcast adherent, having
a good old-fashioned steerable, multielement antenna is quite nice. I can dial in
any TV or FM radio station within 50 miles, and some from over 100 miles away. I
would like to have a similar setup for AM radio, but the antenna length gets out
of hand at 530 to 1,700 MHz (525 to 1,705 MHz including 10 kHz channel
spacing)...
"Researchers in the U.S. and China have made
the first
silk hard drive using a technique called tip-enhanced near-field
infrared nanolithography (TNINL). The device, which can store digital data with
a density of 64 GB per square inch, is robust in the face of harsh conditions such
as heat, moisture, gamma radiation or high magnetic fields. While a silk-based hard
drive is unlikely to match the speed and storage capacity of state-of-the-art solid-state
drives at the same cost, its unique set of features makes it promising for electronics
that could be implanted in the body. Lithography techniques are routinely used to
make devices with optical storage densities as high as several hundred GB per square
inch. However, it can be time-consuming to create small features with these methods,
and it also requires costly and sophisticated fabrication procedures..."
Writing about 'outdated' methods of
radio-based facsimile machine implementation in 1934 seems a bit
incredible considering how relatively new both technologies were at the time. Nevertheless,
Radio-Craft magazine editor Hugo Gernsback reported on the new era of fax
machines that were on display at the 1933 World's Fair in Chicago. Of course fax
machines of that time were not exactly desktop models that could be located in a
corner of your office or cubicle (not that cubicles were common). If you substitute
transistors for vacuum tubes, stepper motors for simple DC motors and solenoids,
and solid state lasers and LEDs for incandescent light sources, the fundamentals
have not changed much...
If you like stories about problems caused
by the "because we've always done it that way" mindset, then you'll appreciate this
"Tales from the Cube" episode by Marshall Bell. While "Tracking
down a Misplaced Oscillation," Mr. Bell applies a seasoned designer's instinctive
method of ruling out potential causes of a problem from the device under test (DUT)
and then verifying the test setup. In this instance, what was likely an expensive
new iteration of an integrated circuit could have been avoided. Yours truly once
solved a longstanding transmitter oscillation issue. Upon starting at a new company,
I was assigned to resolve the problem which occurred after the unit warmed up. Previous
"solutions" involved sprinkling capacitors around the power supply and control lines.
Turns out it was the output transistor voltage biasing scheme causing the problem.
A simple change cured the oscillations over all temperature ranges. Many times a
fresh set of eyes can spot what other highly competent investigators overlook.
TotalTemp Technologies has more than 40 years of combined experience providing
thermal platforms. Thermal Platforms are available to provide temperatures between
-100°C and +200°C for cryogenic cooling, recirculating circulating coolers, temperature
chambers and temperature controllers, thermal range safety controllers, space simulation
chambers, hybrid benchtop chambers, custom systems and platforms. Manual and automated
configurations for laboratory and production environments. Please contact TotalTemp
Technologies today to learn how they can help your project.
September 13th's custom
Radio & Wireless themed crossword puzzle contains only only
words from my custom-created lexicon related to engineering, science, mathematics,
chemistry, physics, astronomy, etc. (1,000s of them). You will never find among
the words names of politicians, mountain ranges, exotic foods or plants, movie stars,
or anything of the sort. You might, however, find someone or something in the otherwise
excluded list directly related to this puzzle's technology theme, such as Hedy Lamarr
or the Bikini Atoll, respectively. The technically inclined cruciverbalists amongst
us will appreciate the effort.
Swan Electronics was another of the many
electronics equipment companies that was started in the founder's garage - literally
- and built a loyal customer following in their areas of specialty. Probably the
most famous example is Bill Hewett and Dave Packard's garage (known affectionately
among enthusiasts as "The HP Garage"). As evidenced by this RF frequency counter
advertisement in QST magazine (six pages worth), Swan manufactured a line of products
for the radio amateur including transceivers, antennas, and a few pieces of test
equipment. Swan Electronics merged with Cubic Corporation in 1967. Information on
this frequency counter and some of the other accessories sold by Swan Electronics
can be found on this Swan Virtual Museum website...
Axiom Test Equipment, an electronic test equipment
rental and sales company has published a new blog post titled "Advances in DC Power Supplies" that offers advice on how to determine
what the specifications need to be for your DC power supply application. Programmability
of many models permits not just setting of constant DC voltage and current levels,
but also in some cases setting of source impedance and creation of complex outputs
similar to those possible with dedicated waveform generators. Often the needs of
a DC power supply for design and development differ from those of production floors
and repair / alignment activities, so you cannot always apply a one-size-fits-all
philosophy. "Advances in DC Power Supplies" is a good place to start your research.
Additionally, user manuals provided by manufacturers are a great source for application
suggestions...
"Managing the heat generated in electronics
is a huge problem, especially with the constant push to reduce the size and pack
as many transistors as possible in the same chip. The whole problem is how to manage
such high heat fluxes efficiently. Usually, electronic technologies, designed by
electrical engineers, and cooling systems, designed by mechanical engineers, are
done independently and separately. But now, EPFL researchers have quietly revolutionized
the process by combining these two design steps into one: They've developed an
integrated microfluidic cooling technology together with the electronics
that can efficiently manage the large heat fluxes generated by transistors. Their
research, which has been published in Nature, will lead to even more compact electronic
devices..."
"My God, man! Drilling holes in his head
isn't the answer! Now put away your butcher knives and let me save this patient
before it's too late!" Those classic words were uttered by Dr. McCoy in "Star Trek
IV: The Voyage Home," after Lt. Chekov (promoted from Ensign after the TV series)
sustained brain damage as a result of falling from a "nuclear wessel" when 20th
century naval surgeons were about to open his skull to relieve pressure from swelling.
Look at these images from a 1932 article on using radio waves "to
produce protective fever in killing germs of a number of diseases."
10 to 30 meters was a popular wavelength band at a power of about 500 watts. The
patient's body part to be treated is placed between the plates to act "as a dielectric"
while the liquids are heated via induced oscillations similar to how a microwave
oven works. How did the doctors know when the treat...
   Incredibly, 18 years has passed since the extremist
Islamic attack on American soil on the morning of
September 11, 2001. Nearly 3,000 citizens died that day. World
leaders have embarked on a path of colonizing our homelands with groups of
people that are known to harbor sympathies for the terrorists. They dwell among
us now and mean to do us harm when opportunity presents itself - which it has on
numerous occasions in the past many years. Never forget the people who died in the
burning towers, the Pentagon, and the airplanes, and those left behind to grieve
and get on with life. Never forget the police and military members who fought -
and some died - to keep us safe and free. Never forget the rotten politicians who
imperil our existence with their selfish agendas.
Qorvo / 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 Qorvo / Custom MMIC today to see how they use their modern
engineering, testing and packaging facility to help your project.
My interest in astronomy really
took off while I was living in the barracks at Robins AFB, Georgia, back in
the 1979-1982 timeframe. Being in the middle of a huge airfield is not the best
place for observing because of all the lights. I discovered that the roof of the
three-story barracks was a good place to escape the human and motorized traffic.
The lock on the roof access hatch in the stairwell had been left off so I would
drag my telescope up there when the skies were clear. The heat coming off the roof
would wreak havoc with viewing, but my telescope was not all that great anyway.
One time while headed to the roof, equipment in tow, a guy I knew stopped me to
ask what I was doing. When I explained about my interest in astronomy, he got really
enthusiastic and began tell me about how he followed the stars, too - as an astrologer.
After politely indulging his story, I continued skyward. From that time on I have
been careful to always emphasize "astronomy" as opposed to "astrology," lest another such encounter ensue. Historically, there
has been a close connection...
"Quantum research in both information science
and sensing shows great promise for enabling a host of new defense applications.
A major hindrance to transitioning breakthroughs from the laboratory to practical
use, however, is the extensive equipment needed to cool and trap atoms to exploit
their quantum features. To address this challenge, DARPA has announced its
Science of
Atomic Vapors for New Technologies (SAVaNT) program. SAVaNT seeks to advance
the performance of room-temperature atomic vapors to enable future opportunities
for unprecedented combinations of low size, weight, and power (SWaP) with performance
across multiple Department of Defense domains..."
There is no arguing that digital multimeters
are vastly superior to
analog meters in many - maybe even most - ways. However, analog
meters still have applications that make them indispensible in situations like monitoring
slow variations in parameters and for quick visual approximations of values. One
example is looking for variation of voltage or current levels under varying loads.
Yes, digital instruments are available that emulate an analog display in certain
modes, but that just proves the point of he usefulness of an analog movement. Another
is the familiar control panel filled with meters where clusters are trimmed to be
centered or at one extreme when the system is running optimally. Yes, effectively
the same result can be obtained with digital readouts and colored status lights...
"San-Francisco-Circuits-Past-Present-Future-Microelectronics-PCB-Production-9-8-2020.htm"
target="_top">
San Francisco Circuits PCB School: How do you
keep up with new developments in microelectronics as devices become smaller and
the space on a PCB becomes even more important? PCB packages keep getting smaller
and smaller and smaller... as the world keeps demanding more dense PCBs. Will microelectronics
be able to meet the new demands in this new world? What does the new world of "San-Francisco-Circuits-Past-Present-Future-Microelectronics-PCB-Production-9-8-2020.htm"
target="_top"> microelectronics and PCB production look like? San Francisco Circuits,
a provider of advanced printed circuit board (PCB) fabrication, assembly, and services,
makes the point that as devices continue to have reduced form factors, precision
in microelectronics becomes even more imperative. Not to mention, smaller PCBs affect
overall PCB design, production, and even assembly...
It's a couple days late for the anniversary
of the September 8,
1966, debut of Star Trek, but this fairly extensive slideshow on the
Smithsonian Institution website has a lot of good information about the history
of the original
U.S.S. Enterprise model used for taping the TV show. The model,
made of poplar wood and molded plastic, was donated to the Smithsonian Institution
in 1974, where it underwent restoration before being paced on display. Overall length
was a little of 11 feet, and the crew saucer had a diameter of about 5 feet. Here
is a short video documentary
of some of the U.S.S. Enterprise restoration work being done. Every few weeks, Melanie
and I watch episodes of the original 3-season series from our DVD set.
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.
When I began reading this piece I wasn't
sure whether it was reporting on interference caused to amateur radio operation
or
interference caused by amateur radio operation. It turns out to
be the latter. Ever since radio operation began in the days of Marconi, unintentional
interference has been a problem. The problem has always been a combination of improper
transmitter and/or receiver filtering. Electromagnetic spectrum regulatory agencies
attempt to assess and address interference through operational band assignments
for particular segments of the spectrum, including how much residual (unintentional)
power can be emitted outside of band or within a defined power mask. Amateur radio
operators are often the first group to be suspected of causing interference, no
doubt due to the "amateur" part of their moniker. In truth, many amateurs are some
of the most knowledgeable and responsible users of the airwaves...
A fascinating article titled "Decoding Numbers Stations" appeared in the November 2019 issue
of the ARRL's QST magazine. Fortunately, it is the month's free article
made available to everyone. I had planned to do some research into it and doing
a write-up but just haven't had the time, so I'm posting this brief intro instead.
Per author Allison McLellan, "Scanning through the bands on AM, you stumble upon
something odd. It might be the last few notes of a folk song, a sound clip from
an old cartoon, or phrases in a different language. A voice cuts through the static,
methodically calling out, 'Mike, India, Whiskey, One, Four…' But this isn't a fellow
ham announcing their call sign. These are numbers stations, an eerie subset of radio
stations that has intrigued hams and non-hams alike for decades. Behind the Voices
Numbers stations are shortwave AM radio stations that transmit messages via voice
or Morse code, believed to be coded in onetime pad (OTP) cryptography. In OTPs,
the message is comprised of strings of numbers or letters assigned to the letters
of the message, based on a pre-determined, randomized key shared between the transmitting
and receiving parties..."
"A new prototype antenna for the U.S. Space
Force has passed a milestone test, the contractors involved announced August 31.
The new multi-band, multimission antenna is under development to address a serious
problem: As the military puts an ever-increasing number of satellites on orbit,
where will the services put all of the antennas needed to connect to them? The
single-phased array antenna can connect simultaneously with multiple
satellites at once over multiple frequencies, even if they are in different orbits.
The prototype could significantly reduce the terrestrial footprint needed to leverage
the Defense Department's growing portfolio of space-based systems..."
All RF Cafe quizzes make great fodder for
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
RF, Microwave, and Millimeter-Wave Components quiz is based on
the information presented in Handbook of RF, Microwave, and Millimeter-Wave
Components, by Sergey M. Smolskiy, Leonid A. Belov, and Victor N. Kochemasov.
The company formerly known as National Instruments
is conducting an online seminar entitled, "Data Acquisition 101: How to Spec and Select Your Next DAQ System,"
on September 22, from noon to 1 PM Eastern. "If you're looking to build a better
DAQ system, start here! We've curated a DAQ checklist to ensure you think of everything
for your next test. In this webinar, we'll review the basics of data acquisition
and provide expert tips to refine your hardware and software selection. You'll learn
how resolution impacts your data and how sample rates might not always be what they
seem. We'll also highlight NI's hardware and software options for DAQ, and help
you choose the right fit for your needs and budget. Join us on September 22, and
get ready to take better data..."
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.
Centralab (Central Radio Laboratories, aka CRL) was a major manufacturer
of capacitors in the early days of radio and television, and pioneered many of the
ceramic compounds that eventually replaced paper and mica as dielectrics. In fact,
according to this 2-page advertisement in a 1951 issue of Radio & Television
News magazine, their researchers mixed and tested more than 20,000 ceramic
compounds while developing a line of capacitors that met strict precision, stability,
and durability tests. It is reminiscent of Thomas Edison reportedly having tried
a thousand or more filament types for his incandescent light bulb before arriving
on a suitable candidate. Centralab did not invent ceramic capacitors, but they played
an important role in their adoption. As with many of the early electronics companies,
Centralab no longer exists. It was bought by Philips...
"RFISee, a developer of affordable imaging
radars for the automotive industry, has unveiled the world's first
phased array 4D imaging radar on a chip. RFISee's all weather
radar has proven its ability to detect cars from 500 meters away and pedestrians
from 200 meters away, with an angular resolution greater than 1 degree. The company's
engineers have adapted Phased Array antenna technology, used in cutting edge military
systems including the F-35 fighter jet and in air defense systems, while at the
same time reducing the price to the current level of automotive sensors. Prototypes
of RFISee's radar are under evaluation by top automotive OEMs and Tier-1s. Unlike
many traditional and new types of radars, RFISee's patented 4D imaging radar uses
a powerful focused beam..."
There are still a lot of vacuum tube guys
out there who might remember enough about them to score well on this quiz that appeared
in the February 1961 edition of Popular Electronics magazine. My own exposure
was mainly with airport surveillance and precision approach radars while in the
USAF. The VHF and UHF aeronautical band radios also contained vacuum tubes, but
we didn't service them. We didn't have a lot of the fancy special purpose tubes
shown here, but I was able to guess correctly on some of them based on how the tube
is constructed and the response curves. Still, I'm embarrassed to tell you my overall
score...
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's
Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart."
My "Matchmaker's" design has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. My markup is only a paltry
50¢ per item - Cafe Press gets the rest of your purchase price. These would make
excellent gifts for husbands, wives, kids, significant others, and for handing out
at company events or as rewards for excellent service. It's a great way to help
support RF Cafe. Thanks...
Empower RF Systems, a leading provider of high-power
ultra-broadband radio frequency (RF) amplifier solutions, is looking for an RF Test
Engineer. The successful candidate will reporting to the Production Test Manager
and partner closely with our engineering teams. The RF Test Engineer develops and
performs test solutions for RF products from concept through manufacturing release.
He/she supports product development evaluations and final product characterization
testing, and works with the development team in providing testability planning,
strategies and methodologies. Specify and recommend test resources, processes, capabilities,
and technology, set-up test circuits to measure the electrical parameters of products...
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.
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. Some quoted items have been shortened
to save space. About RF Cafe.
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