Today in Science History -
You can go to just about any store
these days and buy a tube of RTV (room
temperature vulcanizing) rubber caulk. That was not the case as
recently as the 1960s and 1970s. Here is a short news item about how Dow
Corning Corporation's breakthrough new compound was set to revolutionize
hermetic sealing of critical electronic assemblies. It shows entire
subassemblies of connectors, wires, and discrete components (no ICs at the
time) completely encapsulated in the stuff. I remember at Westinghouse
Electric, where I worked as a technician after a tour in the USAF, we used
RTV for sealing bulkhead-mounted connectors on torpedo heads and towed
sonar arrays. We also used massive quantities of it to seal off machined
metal molds for ceramic transducer element arrays prior to potting them
with a polyurethane compound. That was cool work. The heavy aluminum
molds, about 6-feet long, were placed in a huge, thick-walled aluminum
tube and a vacuum...
Many of us are familiar with
the math behind the Smith chart. Some have written spreadsheets and software
for creating Smith charts, if only for the satisfaction of being able to do
so. It really is quite simple (complex, actually - get it?) to do, but as
with most things a genius mind (i.e.,
Phillip Smith) was
needed to think of doing it in the first place. John Dunn, a very smart guy
in his own right, posted a good primer on the subject on the EDN
website. If you are new to the Smith chart or just want to do a refresh, then
surf on over to read his article, and maybe click on the three related links
at the bottom for more info.
Centric RF is a company offering from
stock various RF and
Microwave coaxial components, including attenuators, adapters, cable assemblies,
terminations, power dividers, and more. We believe in offering high performance
parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz
at power levels from 0.5-500 watts are available off the shelf. Order today,
ship today! Centric RF is currently looking for vendors to partner with them.
Please visit Centric RF today.
Here for your enjoyment are a few more
tech-themed comics from a vintage Radio-Electronics magazine.
Television antenna installations and stereophonic audio systems were a big
deal back in the day, so lots of comics were centered on the themes. Everything
was new and mystical, and ownership of a top-end TV or stereo was a real sign
of influence and/or savvy. The comic from page 96 is actually an advertisement
for Jensen phonograph needles, which of course were key components to the
aforementioned stereo systems. Lost on Millennials (not their fault) and later
is probably the allusion to how the bedraggled couple needing to resort to
a Flintstones-style (also likely unfamiliar to Millennials) record player...
According to this
engineering salary report for 2020, pay continued on an upward trend in
the U.S. despite the Wuhan Flu debacle. Data collected by technology career
Dice indicated the average salary (not including benefits, bonuses, etc.)
of a tech professional in the U.S. increased 3.6% to $97,859 in 2020. Dice
based its numbers on a survey of about 9,000 tech employees - which does not
really seem to me like a very significant sample size. Looking at the bar
chart, most areas reported an increase in salaries, with on the extreme Northwest
cities of Seattle and Portland losing ground. The Silicon Valley area went
from $123,826 to $126,801, a meager 2.4% increase when living in a land where
software developers domicile in their cars due to the cost of housing. Only
augmented and virtual reality (AR and VR) software engineers saw a significant
"Using laser beams to create excited
Rydberg atoms, Army researchers say they built a
quantum sensor to detect the complete radio frequency spectrum. The findings,
published in the Physical Review Applied, show the Rydberg sensor
can pick up Bluetooth, Wi-Fi, AM and FM radio, and other communications signals
on frequencies as high as 20 GHz. Although more engineering and physics
work is necessary, the device has the potential to unleash new potentials
for military communications, spectrum awareness, and quantum electronic warfare
(EW). Using the lasers, rubidium atoms are excited into desired Rydberg states,
allowing researchers to measure atoms' response to an electric field and hone
in on a portion of the spectrum they wanted to measure. Because Rydberg atoms
are extremely sensitive to the circuit's electric fields..."
Oddly, the article does not tell you
the origin of the acronym "WAVES."
From the U.S. Navy's history page: "After a twenty-three-year absence, women
returned to general Navy service in early August 1942, when Mildred McAfee
was sworn in as a Naval Reserve Lieutenant Commander, the first female commissioned
officer in U.S. Navy history, and the first Director of the WAVES, or "Women
Accepted for Volunteer Emergency Service". In the decades since the last of
the Yeomen (F) left active duty, only a relatively small corps of Navy Nurses
represented their gender in the Naval service, and they had never had formal
officer status. Now, the Navy was preparing to accept not just a large number
of enlisted women, as it had done during World War I, but female Commissioned
Officers to supervise them. It was a development of lasting significance,
notwithstanding the WAVES' name, which indicated...
Make Sure That Electric
Car Does Not Run out of Juice
Axiom Test Equipment, an electronic
test equipment rental and sales company, has published a new blog post entitled,
Sure That Electric Car Does Not Run out of Juice," that informs people
who are looking to monitor the battery and charging system of their electric
vehicle (EV), hybrid electric vehicle (HEV), or a plug-in hybrid electric
vehicle (PHEV). Learn how you can maintain a healthy and high performing battery
through our informative guide. In order to ensure that your EV is driving
smoothly, you must do careful maintenance of the battery and powertrains.
Two of the most significant tests includes an internal resistance test and
a battery capacity / discharge test. Doing these tests with the proper equipment
will allow you to see if your EV can handle short circuits, over-voltage conditions,
and over charging...
ConductRF is continually innovating
and developing new and improved solutions for RF Interconnect needs. See the
latest TESTeCON RF Test
Cables for labs. ConductRF makes production and test coax cable assemblies
for amplitude and phased matched VNA applications as well as standard &
precision RF connectors. Over 1,000 solutions for low PIM in-building to choose
from in the iBwave component library. They also provide custom coax solutions
for applications where some standard just won't do. A partnership with Newark
assures fast, reliable access. Please visit
ConductRF today to
see how they can help your project!
About the only kind of transmission
line homeowners use today is 75 Ω coaxial cable for television and Internet
connections. Up until the turn of this new century (two decades old by now
- ugh!), a fair percentage of TV owners still had an antenna mounted on the
roof or maybe rabbit ears sitting atop the set.
Twin lead transmission line was still a common sight as at least the "last
mile" (last few inches, actually) connection via an impedance converter to
the pair of screws on the back of a TV or FM radio. By then, most TVs also
had an "F" coaxial connector for direct attachment without a converter. Internet
connections at the time were telephone cords connected to the modem board
inside your computer. It's hard to believe that was just a relatively few
years ago that we early WWW users got to cross our fingers when dialing up
a local phone number for AOL, Earthlink, Compuserve, Prodigy, Mindspring...
"Even in the world of the smallest
particles with their own special rules, things
infinitely fast. Physicists at the University of Bonn have now shown what
the speed limit is for complex quantum operations. The study also involved
scientists from MIT, the universities of Hamburg, Cologne and Padua, and the
Jülich Research Center. The results are important for the realization of quantum
computers, among other things. They are published in the prestigious journal
Physical Review X, and covered by the Physics Magazine of the American Physical
Society. Suppose you observe a waiter (the lockdown is already history) who
on New Year's Eve has to serve an entire tray of champagne glasses just a
few minutes before midnight. He rushes from guest to guest at top speed..."
Safe-Com Wireless designs and manufactures
wireless communications equipment for first responders. The equipment comprises
boosters and fiber optic distributed antenna systems. The equipment is used
inside buildings to permit the first responder to communicate during emergence
Radio Frequency Test Technician / Associate Engineer position requires
minimum 5 - 15 years direct experience in RF board level testing using a spectrum
analyzer, radio frequency signal generators and similar radio frequency equipment.
The successful candidate will be experienced in reading circuit schematics,
troubleshooting circuits and documenting test results. Also hand soldering
and modification of surface and through-hole printed circuit boards (PCBs)
is required. Direct experience in a production work environment required...
RCA's Numitron was their answer to
the Nixie tube (manufactured by Burroughs Corporation). It was a simpler 7-segment
incandescent display (DR2010) that, with all lines energized, formed the number
8. It worked off of +3.5 to +5 volts, with each element requiring 24 mA
of current. The number 8 drew 192 mA of current and dissipated 0.672 W
at 3.5 volts and a whopping 0.96 W at 5 volts! RCA marketed a BCD*-to-7-segment
display driver (the CD2501E). The
Numitron was pitched as a sensible alternative to the 7-segment LED display,
but with an element size of 0.35" wide by 0.6" high, there was no real advantage
over the LEDs, which were just entering the electronics market in 1970. Numitrons
do have a certain nostalgic 'cool' factor, though. It is interesting to note
that the author's last name, Wood, is the same as that of Frank Wood, who
Teledyne e2v HiRel Electronics, a leading
provider of high reliability semiconductor solutions, today announced a new
high reliability partnership with California-based Integra Technologies, Inc.
(Integra). Under the new agreement, Teledyne will leverage Integra's portfolio
GaN on SiC RF power transistor products to deliver optimized power solutions
for the space market. With Integra, Teledyne e2v HiRel will specialize in
providing high power RF devices for emerging space applications in the LEO
and GEO payload market. Teledyne will also offer high reliability options
for Integra's popular GaN on SiC power devices and pallets targeted at the
defense market. "Our space customers are requesting RF power devices at higher
power density levels and operating at higher frequencies," said Brad Little,
VP and General Manager of Teledyne e2v HiRel. "The combination of our expertise
in providing space...
"The more things change, the more they
remain the same." That old saw has held true throughout the ages, but there
seems to be cycles within cycles that causes, to mix in a metaphor, the pendulum
to swing back and forth in greater and lesser peak amplitudes, and over long
periods of time a bias sets in that causes a perceivable change from the symmetric
tick-tock-tick-tock-tick-tock, to tick----tock-tick----tock-tick----tock-tick.
Without an outside-of-the-system input, the bias grows. If you have a "real"
gravity-driven pendulum clock, you probably know what I mean. Bringing the
system back to symmetry requires adjusting the clockworks movement or "righting"
the physical orientation by rotating the clock on the wall or shimming up
one side on the shelf until the preferred tick-tock-tick-tock is restored.
Economic cycles are much the same, as alluded to in this World War II,
Bonds promotion. There are long periods of overall ups and overall downs,
and in-between there are lesser rises and falls. Eventually, those who learn
to control the cycles tend to insert a bias into the works...