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5 of the September 2020
homepage archives. Monday 28
 According to this 1976 issue of QST
magazine, in 1974 the FCC received 42,000 complaints of
radio frequency interference (RFI). 38,000 of them (90%) involved
interference to home-entertainment devices such as stereos and TV sets. 34,000 (89%)
of were found to be due to design deficiencies in the home-electronic devices themselves.
Since that time, and especially since Wi-Fi and cellphones, the potential for RFI
has increased significantly. Fortunately, thanks to much more stringent compliance
testing, the likelihood of interference from a commercially produced device has
been reduced, but the sheer volume of stuff spewing some level of RF energy has
raised the overall noise floor in heavily populated regions around the world. Concurrently
- and also fortunately - technology advances in filtering, oscillator frequency
stability, shielding, and modulation schemes...
 SF Circuits' specialty is in the complex,
advanced technology of PCB fabrication and assembly, producing high quality multi-layered
PCBs from elaborate layouts. With them, you receive unparalleled technical expertise
at competitive prices as well as the most progressive solutions available. Their
customers request PCB production that is outside the capabilities of normal circuit
board providers. Please take a moment to visit San Francisco Circuits today. "Printed
Circuit Fabrication & Assembly with No Limit on Technology or Quantity."
 PCBONLINE, a global high-end PCB manufacturer
servicing electronics manufacturing (EMS) customers in defense, aerospace, medical,
and other high-end industries, has posted a technical blog entitled, "Comprehensive Guide to SMT Stencils." It answers questions about
what are SMT (Surface Mount Technology) and SMT stencils and what are they used
for, where do you get SMT stencils for PCB assembly, what are the different types
of SMT stencils, and how do you use SMT stencils? SMT (Surface Mount Technology)
stencils are very important for PCB designing and manufacturing. If you can't decide
which type of SMT stencil to go for and you need a detailed guide for this topic,
then you're in the right place. This article will focus on every aspect of PCB stencils
and by the time you reach the end...
 I always learn something new with each episode
of "Mac's Radio Service Shop," but not necessarily related to electronics.
Such is the case in this 1950 issue of Radio & Television News magazine where
after Mac gives Barney a quick lesson in how to determine a transformer's winding
turns ratio when needing to create an impedance match circuit. He then, while discussing
whether 'free' repair estimates are truly free or of any real value at all, he uses
the phrase 'a horse on you.' Maybe it is because I don't frequent bars that I had
never heard that, but after a little research I now know it refers to a bar dice
game called 'Horse.' 'A horse on you' is when you lose the final round of a 2-out-of-3
challenge. 'A horse apiece' is when you and your opponent...
 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...
 "Comparing the relatively simple Fraunhofer
or 'far field' approximation commonly used in radar and high-powered microwave systems
with the more complex near field propagation model based on the field equivalence
principle demonstrates which approach achieves reasonable modeling fidelity with
minimal compute power. Modeling and Simulation can be used to explore the design
trade space of directed energy weapons. M&S can be particularly helpful when
that trade space is influenced by a large number of parameters and when acquiring
field data to explore those parameters requires a large amount of resources. One
example involves the
Active Denial Technology system, a non-lethal, counter-personnel..."
 RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave
component supplier. RF coaxial connectors & adapters, coaxial cable &
cable assemblies, surge protectors, attenuators. Items added daily. Free shipping
on orders over $25. We're leading the way again!
Sunday 27
 September 27th's custom
Engineering 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...
Friday 25
 This is the eighth and final installment
on a "Microwaves" series of articles in Radio-Electronics magazine by author
C.W. Palmer. Each part is a stand-alone tutorial that does not rely on previous
parts to be useful. Unlike most of the preceding articles that dealt in one way
or another with waveguide, this final one concerns "receiving and transmitting antennas for microwave communication."
It touches lightly on various types of antennas, field patterns, impedance matching,
and applications. If you've been around for a while, you've likely seen it all before,
but there are some nice photos of antennas designed and deployed by Bell Telephone
Laboratories for their nationwide microwave telephone relay network. Bell Labs has
done a lot of ground-breaking research in all aspects of communications technology...
 "Designing semiconductor circuits hand-in-hand
with
microfluidic cooling systems could mean huge boosts in efficiency.
The heat generated by today's densely-packed electronics is a costly resource drain.
To keep systems at the right temperature for optimal computational performance,
data center cooling in the U.S. consumes the as much energy and water as all the
residents of the city of Philadelphia. Now, by integrating liquid cooling channels
directly into semiconductor chips, researchers hope to reduce that drain at least
in power electronics devices, making them smaller, cheaper and less energy-intensive.
Traditionally, the electronics and the heat management system are designed and made
separately, says Elison Matioli, an electrical engineering professor at École Polytechnique
Fédérale de Lausanne in Switzerland. That introduces a fundamental obstacle..."
 Alliance Test Equipment sells
used / refurbished
test equipment and offers short- and long-term rentals. They also offer repair,
maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP,
Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization
with ability to source hard to find equipment through our network of suppliers.
Alliance Test will purchase your excess test equipment in large or small lots. Blog
posts offer advice on application and use of a wide range of test equipment. Please
visit Allied Test Equipment today to see how they can help your project.
 Kenneth Wyatt has a good article on the EDN
website entitled, "Quickly Assess Relative Coax-Cable-Shielding Quality." It begins:
"Testing most products for radiated emissions usually requires all I/O and power
cables to be attached to the equipment under test (EUT) and spread out in accordance
with the specific product standard. In many cases, we test engineers simply grab
the nearest cables and hope for the best during the compliance test. Unfortunately,
poor-quality cables can lead to emissions failures due to poor shielding or poor
shield termination (via 'pigtails') to the connectors. In an earlier article, I
related the issue of HDMI cable radiation due to shield pigtails. I also graphically
demonstrate why cable shield pigtails lead to radiated emissions in the video. In
addition to the shield pigtail issue, coax cables..."
 WWV is the oldest continuously-operating
radio station in the U.S. since first going on the air from Washington, D.C. in
May 1920. It moved around an area near D.C. for a few years before being relocated
to its current location in Boulder, Colorado, in 1966. WWVB, another time standard
transmitter, had already been established in Boulder a few years earlier. Sister
station WWVH is located in Hawaii. The National Bureau of Standards (NBS) was renamed
National Institute of Standards and Technology (NIST) in 1988, nearly a century
after its inception in 1890. Having grown up not too far from Beltsville, Maryland,
I remember driving by their main campus when the NBS sign was still on the lawn.
The decision to change the name never did make sense, but then most of what government
bureaucrats do perplex me...
 In response to an article about the ongoing Wuhan
Flu serum development programs, here is one of the cleverest online forum posts
I've ever seen: "This might surprise many of you, but I volunteered for the
vaccine trials for Covid-19. The vaccine is the one that was created in Russia.
I received my first shot yesterday and I'm excited because it seems completely safe,
with иo side effects whatsoeveя, and I feel sκ χoρoshό я чувствую себя немного
странно и я думаю, что вытащил ослиные уши." Plug the Ruskie part into a
translator.
 Aegis Power Systems is a leading supplier
of AC-DC and
DC-DC power supplies for custom and special applications. Aegis has been designing
and building highly reliable custom power supplies since 1995. They offer a complete
line of switch mode power supplies and power converters for a variety of markets
including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft,
EV, telecom, and embedded computing applications. Design and manufacture of custom
power supply solutions to meet each customer's exacting specifications. Please visit
Aegis Power Systems today.
Thursday 24
 Little known to most people (including moi
until recently), DeForest Training School was started by DeVry University's founder
Herman A. DeVry. DeVry and DeForest were DeGood DeFriends, leading DeVry to name
his electronics school after DeForest. It was re-named DeVry Technical Institute
in 1953. Research at DeForest Training School produced one of the first
RF / microwave food baking "ovens." The prototype reported in
this 1951 Radio & Television News magazine article was not at all like
modern microwave ovens. There was no enclosure into which baking bowls, pans, and
dishes can be inserted. Rather, electrodes were arranged at the perimeters of the
special pan that in this demonstration contained cake batter. It was adapted from
a process originally developed for RF induction heating of industrial materials...
 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.
 "Satellite and spacecraft system designers
have a few different options when selecting field programmable gate arrays (FPGA)
semiconductors. One FPGA option is commercial off-the-shelf (COTS) components that
reduce component unit cost and lead time, but they are generally not reliable enough,
must be up-screened (which increases cost and engineering resources), and require
soft and hard Triple Modular Redundancy (TMR) to
mitigate radiation effects in space. In missions where failure
is not an option, designers typically choose higher-cost FPGAs that are radiation-hardened
by design (RHBD). These are already screened and qualified to Qualified Manufacturers
List (QML) Class Q and V standards..."
 "Hobnobbing with Harbaugh" was a regular comic feature in Popular
Electronics magazine in the 1960s. Creator Dave Harbaugh chose topics ranging
from husband-wife relationships where the husband is a technophile of some sort
and the wife either purposely or unknowingly challenges his efforts to participate
in his hobby, to contemporary (at the time) subjects such as this month's treatment
of biocells. Like solid state electronics back in the day, bioengineering was a
mysterious field few understood. It received a great deal of attention by comedians
and sci-fi film makers who got a kick out of scaring people over the possibility
of an alien contamination (a la "The Andromeda Strain") or some secret government
laboratory brewing up a deadly contagion...
 Anatech Electronics offers the industry's
largest portfolio of high-performance standard and customized RF and microwave filters
and filter-related products for military, commercial, aerospace and defense, and
industrial applications up to 40 GHz. One each new
cavity-type duplexer and triplexer have been introduced. The AD1542-1643D296
is an Inmarsat duplexer with 1524-1560 MHz and 1626.5-1660.5 MHz passbands,
and the AD1800-2072-2250TR293 is a triplexer with 2025-2120 MHz, 2200-2230 MHz,
and 1750-1850 MHz. Passband insertion loos is >15 dB on all, and insertion
loss is <1 dB. Custom RF power directional coupler designs can be designed
and produced when a standard...
 On September 29th beginning at Noon EDT, Cadence
| AWR will be presenting a free webinar entitled
NCSU Rabbit Radar - Design, Simulate & Build Your Own Radar at
Home. "In this webinar, Dr. Ricketts describes how to design, simulate, and
build a 2.4GHz frequency modulated continuous wave (FMCW) radar at home or in a
lab. The webinar begins with a short theory session followed by an explanation of
the key components of an FMCW radar, which include a mixer, power amplifier, coupler,
low noise amplifier, and filters. The components will use transmission line structures
that attendees will design...
 NorthEast RF's comprehensive
antenna testing services include linear | circular polarized antenna
measurements and OTA cellular device pre-compliance. Up to 18" diameter and <10
kg weight. Antennas can be rapidly evaluated and optimized using our fast near field
spherical system. Test results supplied in data file with pattern viewer software.
A picture of the test configuration is included to help aligned axis. Our selection
of human head and hand phantoms are ideal for verification of body worn devices.
Turnaround time is usually 3-days.
Wednesday 23
 Use of the word "modern" in titles of books
and magazine articles has always bothered me because of how quickly the referenced
topic becomes obsolete. It is only "modern" for a relatively short period of time.
In 1951 when this article appeared in Radio & Television News magazine,
germanium was the dominant semiconductor in use for
diodes and transistors. They could be used in small signal circuits
of up to about 500 MHz. That meant they could easily replace vacuum tubes in
AM and FM radios, and at least the IF and baseband sections of TVs. You might think
that would have represented a big component cost savings, but semiconductors were
much more expensive than vacuum tubes at the time. Still, the power savings, size
reduction, and higher reliability made the circuit changes worthwhile...
 "A team of researchers at HRL laboratories,
led by Principal Investigator Dr. Jeong-Sun Moon, is developing the next generation
of
Gallium Nitride (GaN) transistors that will have a dramatic effect
on electronic components that amplify electromagnetic signals for communications,
radar, and 5G wireless networks. The ultra-linear monolithic microwave integrated
circuit (MMIC) amplifiers that utilize these high-speed GaN transistors can see
greatly improved linearity, noise reduction, and reduced power consumption. Moon's
team has successfully met and exceeded the performance metrics defined by the Dynamic
Range-enhanced Electronics and Materials (DREaM) program, a DARPA effort to improve
dynamic range in millimeter-wave..."
 Innovative Power Products (IPP), a company with
over 35 years of experience designing and manufacturing RF and microwave passive
components, wants to immediately fill an opening for anRF/Microwave Design Engineer.
The position requires demonstrated success in the design and test of wide band,
high power RF and microwave passive components. Candidate to be familiar with linear
and full-wave EM simulators. Responsibilities include design, simulation, engineering
document release, and prototype test of new products. He/she will communicate with
customers, travel as required to visit customers or vendors, collaborate with Design
and Drafting to satisfy customer requirements. Train and support technicians on
S-parameters, test procedures, troubleshooting, and documentation of product...
 The
Instrument Landing Systems (ILS) has been around since the early
1930s, as made apparent by this article in Short Wave Craft magazine. Frequencies,
circuits, and infrastructure equipment have evolved over the years, but fundamentally,
landing an aircraft (airplane, helicopter, dirigible) under 'blind' flying conditions
has not changed. Two precision beams - one in elevation and one in azimuth - broadcast
by ground-based installations are detected by airborne receivers and relative positions
are displayed for the pilot's use in navigation. ILS does not help the pilot fly
the aircraft; it only leads him to the runway threshold. In the past couple decades,
space-based Global Positioning System (GPS) equipment has increasingly been used
to replace ground-based microwave systems...
 Teledyne e2v HiRel, part of the Teledyne
Defense Electronics Group, today announced the latest addition to its rapidly expanding
line of RF solutions, a new
RF MMIC Frequency Doubler. Launching Teledyne e2v HiRel's new
Frequency Multiplier product line, this Active Doubler, TDFM001000, is designed
for high reliability signal chain applications in Space. It is particularly well-suited
specifically for satellite transponders, transmit/receive modules, microwave-based
communications, millimeter-wave point-to-point radio, and related processes. The
TDFM001000 is a 7.5-25.0 / 15.0-50.0 GHz single ended input (no external balun
required) GaAs MMIC doubler...
 The October issue of IEEE's Spectrum magazine
ran an article entitled, "Let a Thousand Analog Oscillators Sing." It reports on Sam Battle's
"KiloDrone" DIY project consisting of 1,000 analog reverse-avalanche oscillators,
each built with a transistor, capacitor, and resistor. A singe opamp isolates and
amplifies the output of each unit. In his video Mr. Battle explains the project,
runs through the tune-up procedure, and exhibits the final result. According to
the story, only 1.2 A is used from a 12 V DC supply for the entire setup.
There are 10 independently tuned oscillators on each rack-mountable panel. A
printed PCB panel (not including components) can be purchased
for $52. Bob Pease
would have loved this guy whose motivation is summarized thusly: "I like the tangibility
of analog. I hate working on computers. I just can't stand looking at screens. I
like standing up and moving around and making things in a physical world."
 Since 1996, ISOTEC has designed, developed
and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components
and filters for wireless service providers including non-magnetic connectors for
quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM
RF connectors components such as power dividers and directional couplers. Off-the-shelf
and customized products up to 40 GHz and our low-PIM products can meet -160 dBc
with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and
high-performance. Designs that are cost effective practical and repeatable.
Tuesday 22
 When I saw the images in this "Electron Shadows Map Force Fields" article from a 1949 issue of
Radio-Electronics magazine, the first thing I though of was how as kids
back in the 1960s we would hold magnets against the front of the television cathode
ray tube (CRT) to see how they distorted the picture. If I still had a CRT TV or
computer monitor around, I'd take some photos of it for the sake of those who have
never seen what happens. The difference between that and the images formed here
is that the professionals inserted the object of interest directly in the electron
beam, between the cathode and the fluorescent glass grid. As with the images in
the article, magnets of various shapes created unique responses. If you drag the
magnet across the face of the CRT...
 "The evolution of military electronics is
marked by an endless series of
measures and countermeasures. The enemy meets an enhancement in
U.S. fighter jet technology with an improvement in its missile-guidance capabilities,
forcing additional innovations from the U.S. The never-ending effort to enhance
the effectiveness of military technology and protect the warfighter on the battlefield
propels forward innovation in the industry. Today, there's a battle underway that
is dramatically expanding the frequency ranges used by the military for communications
- soldier-to-soldier, soldier-to-satellite, aircraft-to-ground, missile-to-target,
and more. Whereas military electronics used to operate in a narrow band of frequencies,
today, military design engineers must protect equipment from damaging signal interference
and enemy..."
 RF
Cafe visitor Kire P. let me know about a really nice website with lots of information
about EMC (electromagnetic compatibility) and governing industry standards. The
Academy of EMC
is a non-profit based in Switzerland. It has a large variety of downloadable
documents covering EMC guidelines (PCBs, cables, enclosures, etc.) for how to assure
your products will pass testing global, EU, U.S. and other
EMC standards,
including compliance
marks from countries and groups. An educational area contains suggestions for
books and other resources. There are also half a dozen articles on the Blog page.
Keep in mind when reviewing any standard that you must go to the source for
the most up-to-date version. Failure to do so can be quite expensive.
 The Evaluation Engineering website has a
good article entitled, "RF/Microwave Switching Adds Flexibility to Diverse Applications"
that runs through some state of the art hardware available for R&D and production
test setups. It pitches products from multiple vendors, so it is not just an infomercial.
"Engineers in industries ranging from telecommunications to military / aerospace
need high-performance RF/microwave switching as part of their test setups. Consequently,
vendors are offering products ranging from individual switches to complete switching
systems to meet customer demand. This report describes the latest available RF /
microwave switching products and the applications they serve..."
 A while back I was using the familiar
analogy that relates water pressure, hose diameter, and flow rate
to electrical voltage, resistance, and current, respectively, in an explanation
to my daughter regarding why the water characteristics in her house changed after
the well supply pipe and indoor plumbing changed. The cause, I proposed, was due
to an increased distance between well and house, and the use of the plastic PEX
tubing with a smaller inside diameter than the old copper pipe, respectively. The
submersible pump and holding tank still supply the same 50 psi as before, but
since that pressure now has to force the water through a path inside the house with
more resistance to water flow, the delivery rate to fixtures is now lower. When
I hold the contacts closed on the pump control relay, the most I can get is about
55 psi. Raising the pressure will require replacing...
 Fall has finally arrived! The
autumnal equinox occurs today, September 22, 2020, at 9:30 A.M.
EDT (13:30 UTC). The equinox occurs at the same moment worldwide, regardless of
local time zone. The word "equinox" comes from Latin "aequus," meaning "equal," and the Latin "nox," meaning "night." It marks the moment the sun crosses the
celestial equator, which is coincident with Earth's equatorial plane, as it descends
from north to south (south to north transition marks the vernal equinox).
I've never seen this offered anywhere, but why not "equal day" rather than "equal
night?" "Pernox" means day, which would give us equipernox rather than
equinox.
The winter solstice (solstice = sol + stitium ≈ sun stands
still) occurs December 21, 5:02 A.M. EST.
 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.
These archive pages are provided in order to make it easier for you to find items
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