 Friday 21
 According to Electronics
magazine editor Lewis Young in mid-1964, the industry was entering into a slump
in business opportunities. The boom times provided during the war years of WWII
and Korea had resulted in, according to Mr. Young, a lax attitude toward operational
strategy that led to wasteful spending and poor accountability for project results.
It wasn't just the defense contractors' fault because government bureaucrats - from
relatively low ranking military personnel to elected lawmakers - had (have) a habit
of making sudden changes to contract requirements. Maintaining the resources needed
to keep up with ever-evolving demands necessitated a lot of the excess. Fortunately,
the military-industrial complex, as President Dwight D. Eisenhower dubbed it,
was on the verge of being thrown another huge monetary bone - the Vietnam War. President
Kennedy was already pumping lots of equipment and manpower into it, and LBJ would
follow suit with vigor ...
 Rohde & Schwarz just posted their latest
monthly newsletter reporting on topics including
"Measurement of Phase Noise of Local Oscillators" that has a video along with it,
a "Battery Life Optimization in IoT Devices" app note, "Automotive Radar Test Solutions
Using Oscilloscopes" which covers the 77 GHz band, "Optimize Beamforming: From
Bits to RF Beams "using phased arrays. As always, everything is good.
 Power, energy, force, and work are all
physical entities whose definitions are often incorrectly interchanged. As with
most cases in physics, knowing the unit associated with each entity is a way to
remember what it represents. For instance, force is fundamentally understood as
a mass being acted upon by an acceleration - whether it be gravity or motion. Its
SI units are kg·m/s2 (newton, with dimensions of mass x length / time2).
Energy is a force in motion (or its potential by virtue of relative position) with
units of force x mass (joule, with dimensions of mass x length2 / time2),
and an electrical unit of watt·seconds (power x time). Work is force through a distance,
with dimensions of mass x length2 / time2, which is the same ...
 "Computer vision researchers have demonstrated
they can use special light sources and sensors to
see around corners or through gauzy filters, enabling them to
reconstruct the shapes of unseen objects. The researchers from Carnegie Mellon University,
the University of Toronto and University College London said this technique enables
them to reconstruct images in great detail, including the relief of George Washington's
profile on a U.S. quarter. Ioannis Gkioulekas, an assistant professor in Carnegie
Mellon's Robotics Institute ..."
 Transient Specialists specializes in
EMC test
equipment rentals and carries a complete line of ESD guns, surge immunity test
equipment, and EFT generators. Rentals available for military (Mil-Std 461), automotive
(ISO 7637), and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited
calibrations and technical support on EMC testing equipment offered. Equipment consists
of top EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and
EMC Partner.
 Electro-Photonics is a global supplier of
RF &
Microwave components. Their products include SMT hybrid and directional couplers,
wire bondable passive components, mounting tabs, filters, transmission lines, and
very useful test boards for evaluating components (spiral inductors, single-layer
capacitors). The Electro-Photonics team can support your small R&D design requirements
with RF & Microwave test fixtures and save you valuable design and characterization
time. Please take a moment to visit Electro-Photonics' website and see how your
project might benefit. Thursday 20
 There was a time that selecting a
television antenna was as important to the quality of life as buying the right
smartphone is today. There were probably as many choices in antennas then as there
are phones now. You might think, especially if you are not an amateur or military
radio operator, that nobody worries about antennas anymore, but as I've written
before there is a slight resurgence in people installing the old fashioned multi-element
antennas for receiving local television and radio stations. The market's not huge,
but seems to be keeping companies like Channel Master in business. Incidentally,
in contrast to my aforementioned comment, dig the opening sentence of the article:
"Virtually no one in this day and age goes about discussing the reception quality
of his telephone."
 Long-time RF Cafe visitor Alan Dewey, of
JTK Communications, wrote to tell me about the good results he has had with a recently
acquired desktop printed circuit board (DPCB) setup. Alan has been documenting his
experience in a blog on the TwoHourPCBs.com website, and plans to continue as the project
progresses. The particular system he is using can handle 2-layer boards, drill holes,
and perform through-hole plating. Line widths down to 0.20 mm and spacings
to 0.65 mm on FR4 substrate (up to 128 x 105 mm) with pre-applied solder
mask. If you have never tried the DPCB method or were not happy with the way previous
attempts turned out, this might encourage a new trial.
 Popular Electronics magazine used
to run a monthly electronics tutorial column entitled, "After
Class." Various guest authors wrote the articles. All you need to do is substitute
transistors for the tubes used in these fundamental oscillator circuits to bring
this article's content up to date. Or, maybe you are the owner of a vintage vacuum
tube radio and would like to learn a little about how things were done in the olden
days. Either way, as with so many aspects of electronic circuits, the basics haven't
changed much in the last 100 years. It's all still good. A list of all "After Class"
articles is at the bottom of the page.
 While not necessarily directly applicable
to RF communications, Mr. Arthur Pini's article entitled "Eye Diagrams: The Tool for Serial Data Analysis"
on the EDN website does provide some insight into how eye diagrams reveal m-ary
data streams. "The eye diagram is a general-purpose tool for analyzing serial digital
signals. It shows the effects of vertical noise, horizontal jitter, duty cycle distortion,
inter-symbol interference, and crosstalk, all of which can close the 'eye.' While
engineers have used eye diagrams for decades, oscilloscopes continually get new
features that increase its value. Oscilloscopes form eye diagrams - the separation
between the two binary data states '1' and '0' - by overlaying multiple single clock
periods on a persistence display ..."
 "A technique that introduces carbon-hydrogen
molecules into a single atomic layer of the semiconducting material tungsten disulfide dramatically changes the electronic properties
of the material, according to Penn State researchers at Penn State who say they
can create new types of components for energy-efficient photoelectric devices and
electronic circuits with this material. "We have successfully introduced the carbon
species into the monolayer of the semiconducting material," said Fu Zhang, doctoral
student in materials science ..."
 Withwave manufactures an extensive line of
metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a fully automated vector network
analyzer (VNA) calibrator, between- and in-series connector adaptors, attenuators,
terminations, torque wrenches, test probes & probe positioner. Frequency ranges
from DC through 20 GHz. Please contact Withwave today to see how they can help
your project succeed.
Wednesday 19
 In August of 1940, issue No. 24 of the
Radio Trade Digest had a couple major historical announcements. The first
is "F.C.C. Authorizes Commercial F.M.," which assigned 40 UHF (42 - 50 MHz band)
commercial broadcast channels 5 non-commercial channels. Frequencies were changed
to 88 - 108 MHz in 1946. The second major announcement was that Philco (founded
in 1892 as Helios Electric Company, then changed to the Philadelphia
Storage Battery Company in 1906) had become a publically
traded company. It required private stock holders to convert and re-value their
holdings to make some of them available for public sale, which or course they voted
for. I don't know how IPOs worked back then, but my guess is they were not as dynamic ...
 Hewlett Packard (HP), Agilent Technologies,
and Keysight Electronics (all versions of the same company, BTW) have for decades
been offering very cool, colorful, and highly informational (and free)
wall posters that are great for your cubicle
and/or lab walls. Before the ready availability of practically all available technical
resources on the Internet via your smartphone, those posters were an invaluable
source of relevant system specifications, definitions, operations, and formulas.
Keysight has just announced 5 new technical posters and 8 new Keysight Education
Forum (KEF) technical papers and videos.
 Microwave Journal has an article (in infomercial,
actually) entitled "Fabricate PCBs at Your Desk" that describes the
first tabletop LPKF laser etching system, named ProtoLaser ST. As an example
of its capabilities, a planar logarithmic periodic wideband antenna was fabricated
measuring 60 mm x 60 mm. Features as small as 217 um has finished
accuracy errors of around 3%, while those at 1853 um exhibited errors of around
0.1%, depending on the substrate used. ProtoLaser ST is capable of making multilayer
boards and can drill and electroplate through-holes.
 Mr. Orwill Hawkins has a great article
posted on the High Frequency Electronics website entitled, "How Does Match Affect My Power Measurement?"
Some people, particularly - but not limited to - beginners in the RF field, are
not familiar with how VSWR mismatch can affect not just power levels within a systems,
but also frequency response and phase. For instance, when you buy a filter with
a specific frequency response when designed for a 50+j0 Ω impedance and
connect it to another component with a different complex impedance, the measured
response will not match the spec. It might perform well enough, but it won't be
exactly like your predicted response. This article provides a little insight into
the mechanism at work.
 "The
periodic table of elements that most chemistry books depict
is only one special case. This tabular overview of the chemical elements, which
goes back to Dmitri Mendeleev and Lothar Meyer and the approaches of other chemists
to organize the elements, involve different forms of representation of a hidden
structure of the chemical elements. This is the conclusion reached by researchers
at the Max Planck Institute for Mathematics in the Sciences in Leipzig and the University
of Leipzig in a recent paper. The mathematical approach of the Leipzig scientists
is very general and can provide many different periodic systems depending on the
principle of order and classification - not only for chemistry, but also for many
other fields of knowledge ..."
 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.
Tuesday 18
 Your idea of a usable
portable radar probably does not include one that requires you to manually point
it at your surroundings and listen through a set of earphones for a tone's volume
and pitch to estimate distance to the target (or you can use the small analog meter
on the case. That was considered a technological breakthrough in 1971, and Kimball
Product Company's "Whistler" was the star. It only cost $595 ($3,743 in 2019 dollars)
for the capability. The trade name "Whistler" is very well known today, but I could
not find any information relating it to its namesake in this article. There is a
Kimball Electronics, but their About Us page is down at this time. Most likely,
though, it is The Whistler Group that is the progenitor of the radar unit mentioned
here. Today, they have an extensive line of portable radar units for marine, automotive,
aviation, and other applications ...
 An RF Cafe visitor wrote to say he purchased
one of these hand-held
50 kHz to 900 MHz vector network analyzers
for under $100, and was very pleased with its performance. This is a fully self-contained
VNA (S11 and S21 measurements) with all functionality built in, and even has a full
color touch-screen display. Dynamic range runs from 50 to 70 dB, depending on the
frequency band. It does not require an external device for use, although a USB connection
is provided for data transfer (cable included). Two SMA cables and a "simple calibration
kit" comes with it as well. The VNA is sold under a few different names, as are
many of the incredibly inexpensive test equipment items sold online.
 Most people today under 30 years old have
probably never seen the mechanics or electronics inside their many personal devices.
Everything is so miniaturized and optimized that if something does go wrong, there
is little chance of the owner repairing it. Instead, the phone, television, stereo,
microwave oven, whatever, gets thrown away and a relatively cheap (compared to paying
for a repair) replacement is purchased (or stolen). Besides, if the item was more
than two years old, it was on the verge of obsolescence anyway. Up until around
the early to mid 1980s you had a fair chance of being able to repair an electronic
circuit if trouble arose because at least with commercial products
printed circuit boards (PCBs) were usually 1- or 2-sided and the components
still had leads protruding from the sides of the packages ...
 Rohde & Schwarz develops, produces and
markets
test & measurement, information and communications technology.
Focus is on test and measurement, broadcast and media, cybersecurity, secure communications,
monitoring and network testing. Markets serviced are wireless, the automotive industry,
aerospace and defense, industrial electronics, research and education, broadcast
and media network operations, consumer electronics, cybersecurity for business and
governments, communications and security solutions for critical infrastructures
and the armed forces, reconnaissance equipment for homeland and external security,
and much more.
 VidaRF, a manufacturer of high performance
RF and microwave high performance circulators, isolators, couplers, power dividers,
and other passive components, is proud to introduce a series of
broadband directional couplers covering 2 to 40 GHz for all wireless applications
from cellular through 5G mm-wave. Available 10, 16, 20, and 30 dB coupling
values. All models feature low VSWR, high directivity, compact size, and finished
to IP65 standards. 2.92 mm (SMA type) connector standard, with custom configurations
possible. VidaRF is focused on being a solution provider by building to customer
specs and offering zero days lead time for custom parts through stock ...
 "Researchers mixed two optical outputs of
a laser comb and modulated the result, then emitted this energy via an integrated
dipole antenna to create an RF signal in the 5-GHz band. We think of optical lasers
and microwaves as functioning in distinctly different regions and with disparate
modes within the broad electromagnetic spectrum. However, it doesn't have to be
that way, as proven by numerous developments in integrated electro-optics. Now,
in a paper published in the Proceedings of the National Academy of Sciences with
the deceptively modest title 'Radio frequency transmitter based on a laser frequency
comb,' researchers from Harvard's John A. Paulson School of Engineering and Applied
Sciences (SEAS) have demonstrated a laser that can emit encoded microwaves as wireless
RF ..."
Transient Specialists specializes in
EMC test
equipment rentals and carries a complete line of ESD guns, surge immunity test
equipment, and EFT generators. Rentals available for military (Mil-Std 461), automotive
(ISO 7637), and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited
calibrations and technical support on EMC testing equipment offered. Equipment consists
of top EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and
EMC Partner.
Monday 17
 Summer begins this week in the northern hemisphere,
and winter begins south of the equator. Counterintuitive to northerners not familiar
with the geometric cause of seasons (axis tilt) is that the Earth is actually closest
to the sun in January than it is in July. Our orbital path is nearly circular, with
an eccentricity of just 0.0167. Anyway, I thought the onset of summer would be a
good time to post this installment of
Mac's Radio Service Shop entitled, "Summer Seminar." Typical of author John
Frye's techno-sagas, more than one theme runs through the story. It begins with
shop owner Mac admonishing technician Barney for throwing away a faulty selenium
rectifier when he knows there is an industry-wide shortage on supplies of the element
and the bad components should be submitted for recycling. Fretting over as common
an element ...
 Nicholas Estella, Edmar Camargo, James Schellenberg
and Lani Bui, all from QuinStar Technology, Torrance, CA, wrote this whitepaper
entitled "High-Efficiency,
Ka-band GaN Power Amplifiers," which was presented by Mr. Estella at IMS2019
in Boston, Massachusetts. "This paper reports the design and performance of state-of-the-art
GaN MMICs and a fully packaged Ka-band SSPA. Incorporating harmonic tuning, the
MMICs produce power levels up to 10 W CW with efficiencies in the high thirties
(42% peak) at frequencies of 30 to 34 GHz. These results represent the highest
combination of CW power and efficiency at these frequencies. A 4-way combiner-SSPA,
operating over 31 to 34 GHz, was assembled with these MMICs ..."
 Anatech Electronics, an RF and microwave filter
company, has introduced a new line of suspended stripline and waveguide type RF
filters. Sam Benzacar wrote as part of
Anatech's June newsletter about his impressions of the IMS2019 trade show in
Boston. As you might guess, the main topic is 5G and the plethora of technologies
that stand to benefit from the incredible amount of bandwidth assigned to it over
many heretofore largely unused frequency bands. That is part of the challenge, and
the result will no doubt be the conquering of discouraging and difficult implementation
issues. Also included are a few news headlines related to Anatech's core business
of designing and manufacturing filters ...
 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!
 "Antennas made of
carbon nanotube films are just as efficient as
copper for wireless applications, according to researchers at Rice University's
Brown School of Engineering. They're also tougher, more flexible and can essentially
be painted onto devices. The Rice lab of chemical and biomolecular engineer Matteo
Pasquali tested antennas made of 'shear-aligned' nanotube films. The researchers
discovered that not only were the conductive films able to match the performance
of commonly used copper films, they could also be made thinner to better handle
higher frequencies. At the target frequencies of 5, 10 and 14 gigahertz, the antennas
easily held their own with their metal counterparts ..."
 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 Custom MMIC
today to see how they can help your project.
Sunday 16
 Since 2000, I have been creating custom
engineering- and science-themed crossword puzzles for the brain-exercising benefit
and pleasure of RF Cafe visitors who are fellow cruciverbalists. The jury is out
on whether or not this type of mental challenge helps keep your gray matter from
atrophying in old age, but it certainly helps maintain your vocabulary and cognitive
skills at all ages. A database of thousands of words has been built up over the
years and contains only clues and terms associated with engineering, science, physical,
astronomy, mathematics, chemistry, etc. 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 ...
|