See Page 1 |
2 |
3 |
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) ...
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.
Homepage Archive Pages
2024:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2023:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2022:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2021:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2020:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2019:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2018:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2017:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2016:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2015:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2014:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2013:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2012:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 (no archives before 2012)
- Christmas-themed
items
|
