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4 of the August 2019 homepage archives.  Friday 30
 "After
Class" is a long-running feature of Popular Electronics magazine that
covered a very wide range of topics. In most instances a single major theme is presented,
but in this May 1955 issue there are five separate areas: the Faraday shield, binary
notation, using a tuning fork to resonate a tank circuit, and two quizzes (one on
resistance and capacitance and another on power supplies). On the topic of Faraday
shields, I have to tell you about an e-mail I recently received from an RF Cafe
visitor. He wrote asking whether there was any atmospheric pressure at which satellite
radar could not penetrate to the Earth's surface. I could be wrong, but usually
questions like that are asked by people who believe in a government conspiracy to
surviel (and ultimately control) the populace. I used to dismiss such notes as being
from lunatics, but with all the cameras everywhere and the ability to track movement
via cell towers and Wi-Fi hot spots ...
 You definitely
want to check this out! ---
Explore an EMC Control Room & Chamber without leaving your desk. Our new
Interactive EMC Solutions online tool allows you to discover our exceptional range
of Rohde & Schwarz EMC and field test equipment, as well as a custom chamber.
Decades of experience in the field of EMS measurements has made us the world market
leader. By clicking one of the two images, you'll enter a 3D world you control.
Whitepaper: "Comparison of Time Domain Scans & Stepped Frequency Scans in EMI
Test Receivers." Also, learn about the R&S®ESW EMI Test Receiver ...
 Electronics symbols for
schematics and wiring diagrams have remained amazingly consistent for the last hundred
years, although obviously many new ones have been added. You can see from this set
of standardized wiring diagram and schematic symbols from a 1955 edition of Popular
Electronics what I mean. Even symbols for newly introduced devices tend not to change.
There are some variations such as whether or not to draw a circle around a transistor
or how many lightning bolt lines to use with photon emitters and detectors, but
that's about it. The digital world adopted IEEE Standard 91-1984 for logic and microprocessors,
although you will still occasionally see variants in symbols, especially in early
digital circuit schematics. The ARRL publishes its own version of standardized electrical
schematic symbols, but even the ARRL Handbook, in which the symbols are
printed, does not strictly conform to its own standards.
 Here is a good conundrum for you. It
is a good example of how when you make a
measurement that doesn't make sense, the proper
resolution is to analyze and identify the source of measurement error rather than
create a sophisticated mathematical model that produces your measured results. It
reminds me of how early astronomers, assuming an Earth-centric universe, created
exotic models to explain the apparent retrograde motion of planets rather than assuming
a sun-centric system that simplified the math into elliptical orbits. Lots of videos,
including one by Mehdi Sadadhgar - the guy who willingly shocks and burns himself
hilariously while demonstrating electrical principles ...
 "Excess heat given off by smartphones, laptops
and other electronic devices can be annoying, but beyond that it contributes to
malfunctions and, in extreme cases, can even cause lithium batteries to explode.
To guard against such ills, engineers often insert glass, plastic or even layers
of air as insulation to prevent heat-generating components like microprocessors
from causing damage or discomforting users. Now, Stanford researchers have shown
that a few layers of
atomically thin materials, stacked like sheets
of paper atop hot spots, can provide the same insulation as a sheet of glass 100
times thicker ..."
 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 and high quality electronic test equipment. Axiom offers
customers several practical, efficient, and cost effective solutions for their projects'
TE needs and is committed to providing superior customer service and high quality
electronic test equipment. For anyone seeking a way to offload surplus or obsolete
equipment, they offer a trade-in program or they will buy the equipment from you.
Some vintage items are available fully calibrated. Please check out Axiom Test Equipment
today!
Thursday 29
 Although
Heathkit is probably the most familiar line of build-it-yourself electronics products
running from about the late 1950s through the 1980s, there were others. Allied Electronics,
under the brand name of Allied Radio, had a line of "knight-kits"
(many of which can be bought on eBay) that included oscilloscopes, multimeters,
stereo amplifiers, signal generators, citizen band radios, amateur radio transmitters
and receivers, AM/FM radios, vacuum tube test sets, audio and RF generators, and
much more. In the days before just about everything electronic was manufactured
in China by poor souls get paid practically nothing for longs hours of work, it
was often cheaper to buy and assemble a kit than to buy a ready-to-use equivalent
item. It is always interesting to plug prices from vintage magazine ads into ...
 I
don't read contemporary magazines equivalent to The Saturday Evening Post,
so I don't know if advertisements like this one by the
Natural Rubber Bureau still appear. It was quite common in the post-World War II
era for resource companies to promote products used in manufacturing of end-item
production - Alcoa aluminum, Bethlehem Steel, Du Pont cellophane, Anaconda brass
and bronze, American Gas Association natural gas. What caught my eye in this ad
was the right-most picture in the bottom strip. The caption reads, "Flying Squads
Fight Bandits - Communist-led gangs of bandits are still a daily menace in some
of the more remote parts of Malaya. Here a Flying Squad sets up its Bren gun during
a patrol of a rubber plantation." Communist forces have been trying to thwart Capitalism
all around the globe for a long time, just as it is today. The difference is that
today the Communists adopt a form of Capitalism in order to finance their endeavors.
China is a prime example ...
 An article titled
"One Receiver - All Bands" that appeared in the January 1963 issue
of Popular Electronics was a single tube receiver design, but the trick
to using a single tube was that the it was actually three tubes in one - a 6AF11
compactron. It contained two separate triodes and a pentode
within the same glass capsule. A modern equivalent would be to use an integrated
circuit (IC) package that contains three or more opamps in the same package. In
fact, variations on compactrons that included internal biasing components were referred
to as integrated circuits. This article from the October 1960 edition of Electronics
World reported on the engineering behind compactron vacuum tubes ...
 The good folks at
Exodus Advanced
Communications wrote to ask that the company be listed on the
Amplifiers vendor
page, which I was glad to do. "Exodus Advanced Communications is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. As a unique original equipment
manufacturer of power amplifiers ranging from 10 kHz to 51 GHz with various
output power levels and noise figure ranges, we fully support custom designs and
manufacturing requirements for both small and large volume levels. We bring decades
of combined experience in the RF field for numerous applications including military
jamming, communications, radar, EMI/EMC and various commercial projects with designing
and manufacturing of our HPA, MPA, and LNA products in-house."
 "Startup Cerebras will describe at Hot Chips
the world's largest semiconductor device, a 16 nm wafer-sized
processor array that aims to unseat Nvidia's GPUs dominance in training neural networks.
The whopping 46,225 mm2 die consumes 15 kW, packs 400,000 cores, and is
running in a handful of systems with at least one unnamed customer. Also, at this
week's event Huawei, Intel and startup Habana will detail their chips for training
neural networks. They all aim to attack Nvidia which last year sold about $3B in
GPUs for the performance-hungry application. Intel's 1.1 GHz Spring Crest aims to
stand out ..."
 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.
Wednesday 28
 Carl
Kohler has done it again with his mini techno-drama entitled, "R/C Frankie." The
story and Kohler's trademark illustrations appeared in a 1955 issue of Popular
Electronics magazine. When Popular Electronics first began publication
in 1954, it devoted major column space to the topics of amateur radio, home buildable
electronic gadgets, stereo hi-fi recording and playback, and radio controlled modeling.
Here he got a twofer by hitting on R/C and home brew projects. R/C Frankie was an
early conceptual model of the kinds of incredible human-like robots being manufactured
today. It was rather crude in comparison with escapement control of movement and
operation on the interference prone 27 MHz Citizens Band, the latter of which
might have been the root of Frankie's ultimate demise. You'll get a kick out of
the dialog between the self-proclaimed "electronic geniuses" and "the wife" (aka
"friend wife) and, of course, the ending ...
 RF Cascade Workbook 2018 is the next phase in the evolution
of RF Cafe's long-running series, RF Cascade Workbook. It is a full-featured
RF system cascade parameter and frequency planner that includes filters and mixers
for a mere $45. Built in MS Excel, using RF Cascade Workbook 2018
is a cinch and the format is entirely customizable. It is significantly easier and
faster than using a multi-thousand dollar simulator when a high level system analysis
is all that is needed. An intro video takes you through the main features ...
 ConductRF's
LMR RF Cable Assemblies are built exclusively using Times Microwave Systems
class leading LMR range of cable. LMR cables over lower loss than traditional Mil-C-17-RG
cables through their foamed PE dielectric. Exceptional multi-layer shielding with
a multi-laminar aluminum tape bonded to the dielectric provides shielding better
than -90 dB. LMR assemblies offer excellent cost & weight advantages over
other solutions. LMR cables are used extensively in military and commercial applications
operating between DC and 6 GHz. Broad Connector Choice LMR Cables are available
on short lead-times with custom lengths and configurations ...
 Jules Antoine Lissajous
was a French mathematician who in the days before oscilloscopes concerned himself
with patterns (waveforms) that would be generated as the result of two separate
functions (signals) driving both the x- and y-axes. Lissajous used mechanical vibration
devices connected to mirrors to bounce light beams onto a projection surface, so
his results were not merely hand-drawn plots on graph paper. He was probably as
mesmerized with them as we are today when they appear. Sci-fi movies have used Lissajous
patterns in the background to 'wow' the audience into thinking it is witnessing
futuristic, cutting-edge technology. When troubleshooting analog circuits, it is
very advantageous to have seen and recognize many different types of waveforms so
that you have a better chance of picking out patterns ...
 "The Air Force Research Laboratory, in partnership
with several universities, has investigated the effects of
space weather damage to polyimides, materials
used extensively in spacecraft construction due to their high heat resistance. The
researchers determined the previously unknown chemical and physical effects of electron
bombardment in Earth's magnetosphere on these polymers. Electrons trapped in the
Earth's magnetic field are the most damaging components of weather in the geosynchronous
Earth orbit. Polyimide films, such as Kapton, are used to construct spacecraft components,
including flexible printed circuits, electronics, electronic packaging, wiring and
thermal blankets ..."
 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.
Tuesday 27
 Here
is an odd mistake I found in this May 1955 installment of John Frye's "Carl &
Jerry" teen-techno-sleuth article. When Jerry heard a sound coming from the
vicinity of his cohort Carl and did not spy an operating radio anywhere nearby,
he learned that it was coming from Carl's pocket. Turns out it was one of the world's
first transistorized radios that, according to owner Carl, had appeared in the January
1955 issue of Popular Electronics magazine. Being an owner of that issue, I checked
and did not find mention of it there, but I did remember seeing it in the January
1955 edition of Radio & Television News magazine in an article entitled "A New
Pocket Radio," that being the Regency TR-1 transistor radio, priced at $49.95. Why
the confusion, you might ask? Simple ...
 It's almost time for the 2019 EDI−CON
show. EDI CON Online
brings much needed technical training and information directly to engineers' desktops
and mobile devices. Free, real-time training with easy registration and access.
Featuring 3 days of: • Keynotes • Technical Sessions • Workshops & Product Demonstrations
Covering topics in RF, Microwave, Signal Integrity, Power Integrity, and EMC/EMI.
Attendees select their sessions for the online event in a single sign-on registration
portal. Attendees participate live (including Q&A) or watch later on demand.
Sessions include video, traditional webinar, and screen sharing formats.
 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
(FR-4, Rogers, flexible, rigid), Geographical location (U.S., China), kinds of services
(manufacturing, fabrication, assembly, prototype), and more.
One of the perks of attending the International Microwave Symposium (IMS), hosted
by the Institute of Electrical and Electronics Engineers (IEEE), is that you are
given the opportunity to see a part of the history of microwave engineering. At
the two IMS shows that Melanie and I have been to (2009 and 2011), a portion of
the contents of the
National Electronics Museum, headquartered in Linthicum, Maryland, (only a few
miles from the Baltimore Convention Center) was on display. Safely locked behind
protective glass and guarded by a paid sentinel are relics of our profession's past.
Prototypes of magnetrons, circulators, filters, phased array antennas, traveling
wave tubes, waveguide, oscillators, and a host of other devices dreamed up ...
 The Chinese DSLWP-B (LO-94) satellite that
had been in lunar orbit provided a
profile of Earth's HF spectrum as seen from the
moon. The microsatellite subsequently was crashed into the moon's surface after
having completed its mission. DSLWP stands for 'Discovering the Sky at Longest Wavelengths
Pathfinder.' Among other things, DSLWP-B was designed to test low-frequency radio
astronomy and space-based interferometry, and it carried Amateur Radio and educational
payloads. The HF spectrum mission included mapping 'RF interference' from Earth ...
 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!
Monday 26
 When
this article appeared in Popular Electronics in 1955, Iraq was considered a staunch
ally of the United States and most Western countries, although not long thereafter
relations were strained when Communist-aligned forces gained control of the former
monarchy. As part of a plan to help Iraq modernize, English telecommunications company
Pye Limited built and commissioned a television broadcast station in the capital
city of Baghdad. As with any country when television was first introduced, Iraqi
citizens were overwhelmingly enthusiastic - to the extent that TV sets were banned
from being on in store display windows during major broadcasts because of the crowds
being drawn and the subsequent traffic blockages ...
 San
Francisco Circuits (SFC), a provider of PCB fabrication and assembly, has just announced
the company is now offering expanded
PCB tolerances for standard and advanced technology circuit boards. San Francisco
Circuits specializes in offering high-yield PCBs in all kinds of applications that
meet rigid design and performance specifications. San Francisco Circuits' specialty
is in providing solutions to the most complex design challenges and ultra-demanding
applications–be that high-heat, critical-reliability, or even up to military standards
if needed. Their tolerances are built within valid IPC guidelines and standards,
typically IPC-A-600 Class 2 standards that should be followed to help minimize issues
that could affect performance. View San Francisco Circuits' updated PCB Tolerances
here ...
 Capacitors
come in a huge variety of package configurations, chemical makeups, physical constructions
and sizes, capacitance values, and voltage and power handling abilities. Each has
its own strengths and weaknesses for a particular application. When capacitors are
functioning properly, life is great, but when one decides to fail either completely
or partially,
troubleshooting the cause can be a real challenge. The best kind of electrical
component failure from a troubleshooting perspective is one where the component
releases its life-giving internal smoke and in the process leaving a clearly visible
clue like a cracked case or a nice black mark when none should be. Otherwise, the
job can get interesting. Being proficient at schematic reading and tracing waveforms
through circuits ...
 "OneWeb, whose mission is to connect everyone
everywhere, is pleased to announce it has succeeded in bringing into use its spectrum
rights in the Ku- and Ka-band spectrum. To achieve this milestone,
OneWeb's satellites have been transmitting at
the designated frequencies in the correct orbit for more than 90 days, enabling
OneWeb to meet the requirements to secure spectrum bands over which it has priority
rights under ITU rules and regulations. These rights will now be confirmed as the
UK administration, which has filed our satellite system with the ITU, will complete
the required Notification and Registration process of the company's LEO network ..."
 Triad RF Systems designs and manufactures
RF power amplifiers
and systems. Triad RF Systems comprises three partners
(hence 'Triad') with over 40 years of accumulated
knowledge of what is required to design, manufacture, market, sell and service RF/Microwave
amplifiers and amplifier systems. PA, LNA, bi-directional, and frequency translating
amplifiers are available, in formats including tower mount, benchtop, rack mount,
and chassis mount. "We view Triad more as a technology partner than a vendor for
our line-of-sight communications product line." Please check to see how we can help
your project ...
Please check to see how they can help your project.
Sunday 25
 This RF Cafe
Engineering & Technical Headlines Crossword Puzzle contains at least 10
words from headlines posted on the homepage during the week of August 19 through
August 23, 2019 (marked with an asterisk*). These custom-made engineering and science-themed
crossword puzzles are done weekly for the brain-exercising benefit and pleasure
of RF Cafe visitors who are fellow cruciverbalists. Every word and clue - without
exception - in these RF Cafe puzzles has been personally entered into a very large
database that encompasses engineering, science, physical, astronomy, mathematics,
chemistry, etc. Let me know if you would like a custom crossword puzzle built for
your company, school, club, etc. (no charge) ...
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