Today in Science History -
We've all heard of a Van de Graaff
(Robert J.) electrostatic generator, but have you heard of a
Wommelsdorf (Heinrich) generator (aka influence machine)? I hadn't prior
to reading this article entitled "Electric Space Ships" from a 1951 issue
of Radio-Electronics magazine. It took careful reading to get my head around
the propulsion scheme detailed by Professor Hermann. At first I thought he
was describing electric propulsion, but in fact his machine uses electrical
energy generated from the sun to accelerate some form of liquid propellant
via static electric charges. Therefore, this is not a system capable of indefinitely
sustaining itself and its payload (which includes human inhabitants). In fact,
the good professor proposes a geostationary refueling station above the Earth...
"In recent years, physicists and
electronic engineers have been trying to identify materials that could be
used to fabricate new types of electronic devices. 1-D and 2-D materials have
been found to have particularly advantageous characteristics, particularly
for the development of new generations of nanoelectronics (electronic components
at the nano scale). Such 1-D and 2-D materials, such as graphene, monolayer
molybdenum disulfide, silicon nanowires and silicon nanosheets, could also
play a crucial role within the semiconductor industry, as they could help
to develop increasingly small transistors. Despite their well-documented advantages,
emerging low-dimensional materials can have a relatively small amount of so-called
free charges compared to 3-D materials. In the context of electronic components,
free charge is an electron or hole..."
Copper Mountain Technologies (CMT)
is seeking a
Lead RF Design Engineer to develop new VNAs for customers all over the
world. Our USB VNAs are next generation analyzers designed to meet the needs
of 21st Century engineers. Our VNAs include an RF measurement module and a
processing module, a software application which runs on a Windows or Linux
PC, connecting to the measurement hardware via USB interface. The Lead RF
Design Engineer will lead a team of engineers developing new USB VNAs, meeting
new customer requirements, and evolving current product line. This individual
will work closely with product management, manufacturing and other engineering
teams to ensure delivery of quality solutions to customers. Take this opportunity
to join a great company. Preferred location for this position...
Having spent a lot of my career working
for defense electronics companies in classified programs, I am somewhat torn
between sympathizing with Hugo Gernsback from his perspective as editor of
Radio-Craft and what I know is a valid reason for guarding certain
technological information for the sake of military advantage. It is often
the case that people who have had no exposure to the 'black' side of industry
cannot appreciate the need for it. Their argument postulates that suppressing
knowledge does more harm than good because an opportunity for more people
to gain from breakthroughs will result in more rapid advancement in technology.
While that is true, the downside is that the enemy rarely feels obliged to
reciprocate in the same manner, and will exploit your generosity...
Skyworks Solutions, an innovator of
high-performance analog semiconductors connecting people, places and things,
today announced that its high-performance Wi-Fi 6E front-end modules are featured
on the world's first
ultra-fast Wi-Fi 6E gaming router from ASUS. Utilizing the FCC's newly
allocated 6~7 GHz extended band to double the capacity of traditional Wi-Fi,
the Wi-Fi 6E standard enables faster connectivity and supports an increased
number of connected users meeting the unprecedented demand for increased video
conferencing, online gaming, streaming TV, AR/VR, home security cameras and
online exercise apps. An established leader in the networking market, ASUS
is the first to deliver the increased and wider bandwidth 160 MHz channels
of Wi-Fi 6E with its ROG Rapture GT-AXE11000 gaming router...
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.
"Necessity is the mother of invention,"
is an oft-heard maxim that is validated continually. Such was the case, as
pointed out here in this National Union Radio Corporation ad which appeared
in a 1944 issue of Radio-Craft magazine. The development of many
new metal alloys was required in order to obtain the kind of performance and
reliability needed in ever-evolving electronics products. Already available
metals for filaments, coils, grid wires, getters, electron guns and many other
vacuum tubes that are subject to high temperatures (many hundreds of degrees)
and mechanical conditions (unequal coefficients of expansion, for example,
which can cause stress fractures), were not sufficient for the task. Metallurgists
had their work cut out for them...
Empower RF Systems' tactical up-armored
Model 2224 is a compact SSPA operating from 1 to 2 GHz, delivering 150
Watts CW output. The amplifier includes a fast Tx/Rx switch and is designed
for rugged outdoor and tactical deployment of data com links. The all-weather
heavy duty NEMA 4 enclosure houses a complete amplifier system using our Next
Generation architecture so all the local and remote control, monitoring, protections
and user remote GUI are identical to our COTS rack systems. The 2224 comes
complete with internal directional coupler, internal forward and reverse power
sampling and an easy to use remote web GUI. In depth health monitoring can
be viewed remotely and pushed out via the Ethernet port...
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. I also re-broadcast homepage items on LinkedIn. If you need
your company news to be seen, RF Cafe is the place to be.
Advertising begins at $40/month.
The high-tech vehicle you see here
was state-of-the-art in 1935 when engineers at the
at Harvard University outfitted it to do radio research. The story appeared
in QST magazine. The mission of the mobile unit is to enable laboratory equipment
to be carried into the field to make observations on various radio phenomena.
Clad with copper and chromium fittings, the vehicle contained transmitting
and receiving equipment along with various test equipment that included a
high stability frequency reference. In the article a "tungar" charger is mentioned.
A tungar vacuum tube is a high current rectifier with a tungsten element and
an argon gas filler...
Rhode & Schwarz has published a
whitepaper entitled "Optimizing EMI Input Filters for Switched Mode Power
Supplies," which includes an interesting analysis of
differential mode versus common mode noise. "The conducted emissions of
the converter where no filter components are applied is shown in Fig. 4-1.
The top part of the measurement window illustrates the differential noise
emissions (M1) whereas the bottom window shows the common mode noise (M2).
The math which is required to distinguish between the two modes is set in
the math channel menu and visible on the right. The time domain signals are
not shown in detail in the main window because the frequency domain is the
focus in this case study..."
NextPCB is one of the most experienced
PCB manufacturers in China, has specialized in the PCB and assembly industry
for over 15 years. NextPCB provides the most innovative printed circuit boards
and assembly technologies in the highest quality standards, turnaround time
as fast as 24 hours, the lowest manufacturer direct prices, and the most dedicated
customer service in the industry. Turnkey service without a broker including
components sourcing, PCB prototyping, manufacturing, assembly, quality testing,
and final shipment. Certified by IATF16949, ISO9001, ISO14001, UL, CQC, RoHS
Radio Technology Theme crossword puzzle for January 17th contains only
words and clues related to engineering, mathematics, chemistry, physics, and
other technical words. As always, this crossword contains no names of politicians,
mountain ranges, exotic foods or plants, movie stars, or anything of the sort
unless it/he/she is related to this puzzle's technology theme (e.g., Hedy
Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst
us will appreciate the effort. Enjoy!
"Portable" is a matter of perspective
when it comes to large systems. Anything that can be put on wheels and moved
over land is technically portable, but the speed at which it can be brought
into operation once relocated is what really defines whether something is
portable or not. To be truly portable, all of the requisite support equipment
must travel with it; e.g., electric generators, fuel, water, food, personnel
facilities (if needed), etc. The MPN−14
portable airport surveillance radar (ASR) and precision approach radar
(PAR) unit I worked on in the USAF truly qualified since it was entirely self-contained
and the necessary power generators were supplied by a separate shop within
the 5th Combat Communications Group to which I belonged. Other shops provided
creature comfort facilities, ground-based and satellite radio communications,
tactical air navigation (TACAN), security, and managerial services. A few
times each year we had what were called "Healthy Strikes" where claxons would
sound in the barracks...
On Wednesday, January 20th at 2:00
PM EST (GMT -5:00), Copper Mountain Technologies will present another of its
VNA Master Class Webinar series entitled "Materials
Measurement at 5G Frequencies." This webinar will demonstrate the use
of free-space spot probes to characterize materials at 20 to 40 GHz,
of interest to new 5G millimeter wave frequencies. A table-top measurement
system using CMT's S5243 VNA will be used to determine transmission and/or
reflection of materials. From these measurements, the webinar will discuss
the calculation of dielectric properties of measured materials. The agenda
consists of free space measurement description, example measurements &
dielectric calculation and a Q&A session at the end...
Ha, I thought WA referred to Washington
state, but not so. It's a good thing because I was going to accuse them of
using a phony photo that includes the Large and Small Magellanic Clouds which
are not visible from Washington! "A remote outback station about 800 km
north of Perth in Western Australia is one of the best places in the world
to operate telescopes that listen for radio signals from space. It's the site
of CSIRO's Murchison
Radio-astronomy Observatory (MRO) and is home to three telescopes (and
soon a fourth when half of the Square Kilometre Array, the world's largest
radio telescope, is built there). But it's important these telescopes don't
pick up any other radio signals generated here on Earth that could interfere
with their observations. That's why the observatory was set up with strict
rules on what can and can't be used on site..."
Before the current generation began
destroying its hearing with smartphone earbuds, their parents and grandparents
(that includes mine) destroyed our hearing with ridiculously
powerful loudspeakers, often in boom boxes perched on shoulders right
next to the ears (not me). The "concert hall" - or concert auditorium - experience
has been long sought-after since recorded music has been available, which
has only been about a century. As evidenced by the sudden increase in articles
and advertisements in my growing collection of vintage electronics magazines,
the early and mid 1950s saw a sudden swell of articles promoting the equally
swelling supply of high fidelity (hi-fi) recording and playback equipment
hitting the markets. Subjects ranging from homebuilt projects to reports of
top end commercially products filled the pages each month. Television saw
the same treatment in the late 1950s and early 1960s...
Qorvo, a leading provider of innovative
solutions that connect and power the world, today introduced two
Wi-Fi 6E front end modules (FEMs) designed to maximize throughput and
range in high-bandwidth applications such as 8K video streaming, online gaming
and virtual reality. Wi-Fi 6E is an extension of Wi-Fi 6 that operates in
the recently opened 6 GHz frequency band, in addition to the traditional
2.4 GHz and 5 GHz bands. Wi-Fi 6E triples Wi-Fi capacity with contiguous
spectrum to accommodate 7 additional 160 MHz-wide channels or 14 additional
80 MHz channels. Qorvo's Wi-Fi 6E FEMs unleash the full potential of
this new spectrum, delivering leading linearity performance and maximizing
throughput and capacity at peak permissible indoor power levels...
Have you been looking for a Zenith
Radio Nurse, a Superior Speedometer Multitester, or maybe a Clough Brengle
3" Oscilloscope? Perhaps you happen to have a wireless phono oscillator, a
Weston 722 radio, or a Dumont 3" model 164E oscilloscope for sale. In either
Sprague Trading Post would have been the place to go in the mid 1940s,
when the company paid good money in Radio-Craft magazine to host a swap shop
for electronics hobbyists and professionals. Vacuum tubes, radios, test equipment,
and related items were offered and requested. Sprague was/is a major manufacturer
of capacitors, so they probably figured some of the equipment would need replacement
capacitors which traders would buy from them...