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4 | 5 of the June 2019 homepage archives. Friday 14
 If you read the physics and geographic news
of the day, most likely you have seen articles on the rapidly increasing
migration rate of the geomagnetic "north pole" over the past few
decades. Magnetic north has never exactly lined up with geometric north (as borne
out in geological samples of rocks), and neither has it ever been uniformly distributed
across the globe. Ancient explorers on terra firma and at sea knew that a magnetic
compass needle did not align with the same stars, moon, or sun position for every
location, after accounting for difference in longitude. That is because the earth's
magnetic field is very nonuniform in strength and does not follow straight lines
from pole to pole as they more generally do from outer space. A correction factor
must be applied to any magnetic north indication based...
 ConductRF, a premier manufacturer of standard
and custom RF cable assemblies, announces the availability of
Precision Ruggedized VNA Cables from ConductRF offer RF Engineers
great alternatives to costly OEM cables that are now past their best days. We have
standards for applications at 18 GHz, 27 GHz, 40 GHz, 50 GHz &
70 GHz. Our torque resistant connector heads and phase stable constructions
ensure great performance for many tests to come. VNA Series cables are enhanced
with a stainless steel spiral armor, providing protection from excess bending and
crushing forces. A black non-conductive outer cover completes the product. These
cables are phase stable during flexing and have an operating life cycle of up to
5,000 matings...
 An
iconoscope was an early form of television image capturing tube. Some amateur
radio operators were experimenting with slow scan TV even back when the technology
was relatively new to the world. When this article was written in 1944, there were
still large portions of the United States that did not have television broadcast
coverage. Of course I would argue that at the time of my growing up in the 1960s
and early 1970s a lot of areas - even suburbs - were still not covered by TV signals,
based on how cruddy the reception at my parents' house was. But I digress. The article
mentions that because of the lack of TV coverage, many amateurs did not even have
television receivers (TV sets) in their homes to use along with experimental television
transmitters...
 "Welcome to the first issue of
CAS News from Cobham Antenna Systems! Inspired by the richness
of late-spring, we decided to launch this bi-monthly newsletter, to help keep everyone
informed of all the exciting developments going on here at Cobham Antenna Systems
(CAS), in Newmarket, UK. In this issue, the first of many to come, we cover our
presence at two recent key industry exhibitions: AUVSI / Xponential 2019 in Chicago,
USA, and EW-E 2019 in Stockholm, Sweden. At these shows we introduced a new antenna
that is designed specifically for C-UAS (that is, Counter-Unmanned Airborne Systems).
We also take a look at how we are helping Professor Alan Wilson...
 "Researchers from Kyushu University, Japan,
have demonstrated lasing from an electrically driven
organic diode. Reporting their findings in the journal Applied
Physics Express under the title 'Indication of current-injection lasing from an
organic semiconductor,' the researchers circumvented the traditional issues of organic
materials (which due to their inherent resistance, tend to break down under the
high currents required for lasing). A critical step in lasing is the injection of
a large amount of electrical current into the organic layers to achieve a condition
called population inversion ..."
 Nova
Microwave is a leader in technically differentiated electronic and radio frequency
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Thursday 13
 Everything is relative... just ask Albert
Einstein. The use of terms like "contemporary," "modern," etc., in the titles of
books has always annoyed me. They would be okay if the titles also included the
year or at least the decade to which the claim applies. Not quite as nefarious is
the claim of "high frequency" when describing electronics components since it is
safe to assume that most readers understand the era to which it applies. To a lesser
extent that goes for "high voltage" and "high current." This 1964 advertisement
for Motorola's
Oxide-Passivated Silicon Annular Transistors appeared in Electronics
magazine touting the high frequency capability...
 As we approach the 50th anniversary of the
Apollo 11 moon landing, many magazines are publishing articles about the event
and the background leading up to it. I have tagged a couple notable quotes from
astronauts involved that will be posted over the next month or so. The June issue
of Discover magazine included this one as delivered by
Neil Armstrong to the National Press Club: "I am, and ever will be, a white-socks,
pocket-protector, nerdy engineer, born under the second law of thermodynamics, steeped
in the steam tables, in love with free-body diagrams. ... Science is about what
is. Engineering is about what can be." Amen, bro.
 The
CMD299 is a highly efficient GaAs MMIC low noise amplifier ideally
suited for EW and communications systems where small size and low power consumption
are needed. The device is optimized for 30 GHz and delivers greater than 17 dB of
gain with a corresponding noise figure of 3.5 dB and output 1 dB compression point
of +7 dBm. The CMD299 is a 50 ohm matched design which eliminates the need for external
DC blocks and RF port matching. The CMD299 offers full passivation for increased
reliability and moisture protection...
 Andrei Muller, of the Swiss Federal Institute
of Technology in Lausanne will present his
3D Smith Chart
software during the
PRIME 2019 event on Monday, July 15th. The talk will start by presenting the
mathematics behind the Smith chart and extended 2D Smith chart from the group theory
of geometry point of view (Kleinian view of geometry). Using the Maxime Bochert-Klein
results on Mobius transformations (among which the Smith chart constitutive equation
belongs). The introduction will show what happens by applying the voltage reflection
coefficient transformation and power wave reflection coefficient transformation
on the grid of the impedance plane, random geometrical objects and photos. The geometry
of these mappings will be then compared with the geometry of other scattering parameters
mappings when applied to the same objects...
 "A new method to develop 2D materials, called
transition metal dichalcogenides, paves the way for novel applications
in optoelectronics and other next-generation electronic devices. The promise of
2D graphene material for next-generation electronics is well-known - because of
its high conductivity and light weight. However, there are many other 2D materials
that also can be used in future electronics applications to bring new and improved
characteristics. Some of the materials in which researchers are particularly interested
are a group of semiconductors called transition metal dichalcogenides, or TMDs.
These materials, a few atoms thick ..."
 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
(e.g., material, flexible, rigid), Geographical location, and more.
Wednesday 12
 Many months have passed since I last posted
one of the Radio Service Data Sheets for vintage radio sets. This one for the
Sentinel Model 217-P portable appeared in the August 1940 issue
of Radio-Craft magazine. Hobbyists and professional electronics service
shops relied on these back in the day because obtaining the information from manufacturers
could be difficult or even impossible. Some companies would not provide service
information for alignment and troubleshooting to businesses that were not officially
endorsed to do so. That left some of the smaller shops and most do-it-yourselfers
without a means to work on sets. Once places like SAMS Photofacts came along with
information packets that could be purchased...
 Carl and Jerry found the appearance and construction
of
2,400 megacycle transmitters and receivers to be quite odd compared
to the equipment they were used to dealing with. It's sometimes hard to believe
such an attitude of wonder when our world today is utterly filled with wireless
devices operating in the 2.4 GHz ISM band. Author John T. Frye could never
have imagined that such a reality would would exist half a century after his story
of the pair of teenage electronics sleuths. Unlike our postage stamp size integrated
assemblies that cost a few dollars, they speak of "special ultra-high-frequency
'light-house' tubes with a cavity resonator clamped on top of them." Back to the
story, though... Did you know that police were using radar guns as far back as 1963?...
 Listen in on our latest news as our very
own CEO Paul Blount proudly presents
Custom MMIC's Women in Engineering scholarship last Wednesday,
June 5th 2019 at the International Microwave Symposium in Boston. In this quick
podcast, meet the first three recipients of the scholarship: Sarah McKinley, Emma
Fournier and Grace Remillard. Blount describes each of the women as "so talented."
 This latest report by the Interesting
Engineering website lists a state-by-state accounting of
mechanical engineers' salaries. Data was assimilated from the
U.S. Bureau of Labor Statistics (BLS). The Bureau projects a 9% job growth rate
form 2016 to 2026. The average salary went from $90,340 in 2017 per year to $92,800
in 2018, which represents a 2.7% increase. That is just about on par with the 2-3%
inflation number claimed by the BLS. The value of benefits is
not included. Alaska had the highest average pay at $128,69, while Arkansas came
in last with $71,730. On a side note, I've always been critical of multistate companies
having different pay scales for people doing the same jobs at various locations.
Sure, cost of living differs, but ultimately they are paying employees unequally
from a corporate accounting perspective.
 "Chinese Amateur Satellite Group (CAMSAT)
has announced the impending launch of the CAS-7B satellite, also designated as BP-1B,
a short-lived spacecraft that will carry an Amateur Radio payload. An unusual feature
of the spacecraft is its 'sail ball' passive stabilization system. The 1.5-U CubeSat is
attached to a 500-millimeter flexible film ball - or sail - that will offer passive
'pneumatic resistance' stabilization. CAS-7B is expected to remain in orbit for
up to 1 month. The spacecraft will carry an Amateur Radio transponder and educational
mission. CAMSAT is working with Beijing Institute of Technology (BIT), a top aerospace
school ..."
 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.
Tuesday 11
 In the light of having just marked the 75th
anniversary of the D-Day (Operation Overlord, June 6, 1944), which marked the beginning
of the end of Hitler's ruthless siege on all of Europe, please note how Electronics
magazine editor Lewis Young cites, in 1964, the continued rebuilding of Europe as
the reason many - maybe most - companies there are still, two decades later, concentrating
engineering and financial resources on getting back on a solid footing rather than
chasing after the latest and greatest in
nonessential technologies. It was probably an accurate assessment
of the situation. However, I do take issue with his admonishment to American companies
to emulate Europe's "practical approach" to innovation and manufacturing. There
was absolutely no reason to dissuade and throttle activity here...
 Custom MMIC, a leading designer and manufacturer
of high performance monolithic microwave integrated circuits (MMICs), has posted
a new blog entry entitled, "Advanced MMICs Aid in Reducing Size and Power in Phased Array Radar
Systems." Phased-array radar systems are important instruments in national electronic
defense strategies. From the large, ship-based systems that scan for distantly launched
missiles to the more compact arrays installed on fighter aircraft and unmanned aerial
vehicles (UAVs), electronic phased-array radars come in many sizes and forms, providing
reliable signal detection and identification. These modern systems offer many advantages
over earlier radar...
 There is
a plethora of special purpose calculators and units conversion resources available
online. As with most things on the Internet, you need to verify the accuracy of
results when using any of them for the first time. One units conversion website
I have used many times for swapping between SAE and metric units, and when needing
to find alternate forms of electrical units like volts/meter to Newtons/coulomb,
is UnitConverter.net. A nice
feature is that the equivalent numerical values are instantly displayed for all
alternate units as well as for the new units you are seeking. I did not find a
furlong per fortnight unit for speed, though ;-) The site also provides
an assortment of calculators.
 Ward Silver (N0AX) wrote a monthly column
for the ARRL's QST magazine for nearly decades before shifting over to
Nuts & Volts a couple years ago. Mr. Silver nowadays writes "The
Ham's Wireless Workbench," which as the title implies addresses the RF and microwave
aspect of electronics to complement the analog and digital aspects of the magazine.
In the March/April 2019 issue is an article entitled, "The Smith Chart," a subject that can make a grown man cry upon
initial introduction. Ward, in his inimitable style, helps make the subject approachable.
Only the first two pages (of six) are available online, so you will need to either
pay for full access or do as I do and get a copy from the public library.
 This was predicted, but it doesn't matter.
"It looked like a scene from a sci-fi blockbuster: an astronomer in the Netherlands
captured footage of a train of brightly-lit SpaceX satellites ascending through
the night sky this weekend, stunning space enthusiasts across the globe. But the
sight has also provoked an outcry among astronomers who say the constellation, which
so far consists of 60 broadband-beaming satellites but could one day grow to as
many as 12,000, may threaten our view of the cosmos and deal a blow to scientific
discovery. The launch was tracked around the world and it soon became clear that
the satellites were
visible to the naked eye: a new headache for researchers who already
have to find workarounds to deal with objects cluttering ..."
 Anatech Electronics (AEI) manufactures and
supplies RF and microwave
filters for military and commercial communication systems, providing standard
LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard
RF filter and cable assembly products are published in our website database for
ease of procurement. Custom RF filters designs are used when a standard cannot be
found, or the requirements dictate a custom approach. Sam Benzacar's monthly newsletters
address contemporary wireless subjects. Please visit Anatech today to see how they
can help your project succeed.
Monday 10
 Prior to phasing-based single sideband generation
circuits, a brute force filtering of the unwanted sideband and carrier signals was
required. Depending on how well the carrier was suppressed, more than half the total
signal power could be lost. According to author Jack Brown in this "Commercial Aspects of Single-Sideband" article from a 1956 issue
of Radio & Television News magazine, it had only been since the mid
1940s that wide-band audio-frequency phase-shift networks were even feasible. An
ideal implementation of a single-sideband suppressed-carrier modulator (SSB-SC)
would result in 100% efficiency, but typical results are in the 80% range...
 The Engineer website just posted the
results of its "The Engineer's 2019 Salary Survey." As you can see, this is primarily
an UK survey (understandable since The Engineer is a UK entity), and the
result shows, "a significant increase in engineering pay." It reports by industry,
not specific types of engineer; e.g, electrical, mechanical, etc. Energy / renewables
/ nuclear is the top paying field at £58,695 ($74,377), Telecoms & utilities
/ electronics fell in the middle at £51,825 ($65,711), and academia came in last
at £43,830 ($55,574). Those numbers do not incorporate benefits and, in the case
of academia, the value of job security in the form of tenure.
Since 1961, MECA Electronics has designed and manufactured an extensive line
of RF & microwave
components for in-building, satellite, radar, radio, telemetry, mobile radio,
aviation & ATC. Attenuators, directional & hybrid couplers, isolators &
circulators, power dividers & combiners, loads, DC blocks, bias-Ts and adapters &
cables. MECA has long been the 'backbone' of high performance wired and air-interfaced
networks such as in-building applications, satellite communications, radar, radio
communications, telemetry applications, mobile radio, aviation & air traffic
communications.
 This is cool. I saw a U.S. Air Force recruitment
advertisement in a 1960 edition of Popular Electronics pitching careers as radar
operators (air traffic control) and technicians (maintenance). The picture has the
dual-display
glide path and elevation sweeps from the MPN/13/14 radar system
that I worked on in the late 1970s - early 1980s. A photo I took circa 1980 of our
unit based at Robins AFB, Georgia, is shown below. The precision approach radar
(PAR) operated at x-band (10 GHz) with an operational range of 10 nautical
miles. The azimuth and elevation antennas were mechanically swept with motors that
changed the geometry of a waveguide having dipole stubs along its length. The entire
PAR system...
 Clear Microwave,
of Malvern, PA, manufactures an extensive line of N-way dividers / combiners (reactive &
resistive), high power combiners, directional couplers, 90° & 180° 3 dB
hybrids couplers, RF switches, phase shifters, limiters, detectors, bias Tees, and
DC blocks. Frequency ranges for products range from DC to 40 GHz, with CW power
handling to 500 W, depending on device.
 "DARPA's Spectrum Collaboration Challenge
demonstrates that
autonomous radios can manage spectrum better than humans can.
In the early 2000s, Bluetooth almost met an untimely end. The first Bluetooth devices
struggled to avoid interfering with Wi-Fi routers, a higher-powered, more-established
cohort on the radio spectrum, with which Bluetooth devices shared frequencies. Bluetooth
engineers eventually modified their standard - and saved their wireless tech from
early extinction - by developing frequency-hopping techniques for Bluetooth devices,
which shifted operation to unoccupied bands upon detecting Wi-Fi signals. Frequency
hopping is just one way to avoid interference, a problem ..."
 Axiom Test Equipment
allows you to rent or
buy test
equipment, repair
test equipment, or sell
or trade test equipment. They are committed to providing superior customer service
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Please check out Axiom Test Equipment today!
Sunday 9
 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...
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.
About RF Cafe.
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