See Page 1 |
2 |
3 |
4 | of the June 2020 homepage archives.
A few weeks ago I posted a two-part article
on the Taylor
super-modulation principle published in Radio & Television
News magazine in 1948. It was a newly announced technology at the time and
was written by its inventor, Robert Taylor. This piece titled "Understanding Super-Modulation"
appeared a couple years later by another author, John McCord, where he describes
how it works , how to tune super-modulation circuits, and how it compares to other
modulation methods - all conveniently in "Ham language." Super-modulation is a form
of amplitude modulation (AM) that makes use of carrier and/or sideband suppression
to achieve greater efficiency. A panadaptor - aka pan-adapter, aka panadapter, aka
radio spectrum scope, aka panoramic adapter - is used to view the RF spectrum across
a wide band. Essentially it is a low budget spectrum analyzer...
"Directed energy weapons like this Northrop
Grumman laser will provide the Navy new options for dealing with new threats. The
U.S. Navy demonstrated a solid state laser weapon mounted on the amphibious transport
dock ship USS Portland May 16, shooting down a target drone near Pearl Harbor, Hawaii.
The
Laser Weapon System Demonstrator (LWSD) was developed by Northrop
Grumman and integrated with full System and Ship Integration and Testing led by
Naval Surface Warfare Center Dahlgren and Port Hueneme. The Navy said that the operational
deployment of the LWSD is the first system-level implementation of a high-energy
class solid state laser..."
Studies of motors usually begin with the
direct current (DC) type - maybe because most students have already had hands-on
experiences with
DC motors in models (cars, boats, airplanes) and/or electricity
experimenter kits. They are small, cheap, and a simple flashlight battery (the ultimate
in safety) makes them run. An alternating current (AC) motor requires either a direct
connection to the house current or use of a step-down transformer, which still carries
with it a high risk factor. This chapter of the U.S. military's Basic Navy Training
Course (NAVPERS 10622) conforms to the tradition, and follows in the next chapter
with AC motors and generators. While reading through the text, I ran across the
unfamiliar term "kickpipe" and wondered how I could have missed that after so many
decades of working with motors - both DC and AC. I didn't feel quite so dumb after
looking up the definition; after all, I was in the Air Force, not the Navy ;-)
"Keysight-Technologies-Tools-Design-Simulation-Test-mmWave-Innovations-6-11-2020.htm"
target="_top">
Keysight Technologies will showcase its suite
of software tools for design, simulation and test at the "Keysight-Technologies-Tools-Design-Simulation-Test-mmWave-Innovations-6-11-2020.htm"
target="_top"> Millimeter Wave Innovations event on June 23rd, 24th, and 25th, beginning
at 9:00 am PDT. What: Next-generation wireless systems are targeting a range
of new capabilities including higher bandwidth, more connected devices, and low
latency. Millimeter wave technology is a key enabler for this upcoming wireless
revolution and Keysight solutions deliver accurate, repeatable results at ever-higher
frequencies and wider bandwidths. Training courses and virtual demonstrations of
advanced tools for design, simulation, and test...
Ed Troy, owner of Aerospace Consulting, was
kind enough to offer a few of his articles for posting on RF Cafe. With more than
30 years in the electronics communications design field, Ed has a lot of valuable
knowledge to impart to us mortals ;-) This third paper demonstrates why using a
highly capable software simulator for system design work is essential because of
its ability to predict and facilitate mitigation of system-generated problems prior
to building and testing the prototype. Case in point are
spurious spectral components generated by the local oscillator
and SSB to PM conversion created in a frequency doubler circuit. This paper was
adapted from an example circuit provided in Keysight (formerly Agilent) Genesys
Spectrasys. Spectrasys is a spectral domain block diagram simulator that allows
the user to construct a system model and quickly determine the system performance.
Whether you are involved...
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.
Do you remember your first calculator - electronic,
that is (slide rules and abacuses don't count - actually they do, right?)? Mine
was acquired sometime in the fall of 1976 during my first attempt at secondary education
at Anne Arundel Community College in Maryland, where eventually, in 1987, I was
awarded an Associate's degree in Engineering (which constituted the first two years
of my eventual BSEE at UVM in 1989, on whose notable alumni list I am not). My name
is not in AACC's list of notable alumni, either. But I digress. My calculator was
a Texas Instruments model SR-50 that had a small red LED display. It cost about
$100 ($445 in today's inflated money) and performed basic math with a few simple
trigonometric and logarithmic functions. This edition of Mac's Service Shop, entitled,
"Buying and Using a Pocket Calculator," has Mac telling sidekick
Barney about the Hewlett Packard's HP-45 calculator. According to the Wikipedia
entry, the HP-45 entered the market in 1973 at a list price of $395 ($2,084 today).
That's the price of a high-end gamer's computer these days. Its features were about
equal to my $100 SR-50 a decade later. For the budget minded calculator, he also
recommended the Unicom Model 202SR...
As you might know, particularly if you are
a frequent RF Cafe visitor, amateur radio operators (Hams) were prohibited from
broadcasting during the entirety of World War II, ostensibly as a security
measure. The concern was that people might unintentionally (or intentionally) convey
information on troop positions and family names, domestic factory locations and
activities, and the general state of the nation in regards to attitude and finance.
Unlike today, that type of data was not easily gathered even by a dedicated deployment
of internal spies. In the early 1940s, the majority of amateur radio activity was
carried out in the form of Morse code, and operators were understandably concerned
about losing proficiency due to lack of use. In order to mitigate the opportunity
for "fist" atrophy, many Hams set up "wired
wireless" stations between residences and club meeting locations. This particular
system was designed to couple to the local overhead electric power lines, but there
were also private setups with dedicated lines between locations. Then, as now, one
of the biggest hurdles with conducting power-line carrier communications...
Ruh-roh, bad news for THz plans. "Researchers
from the RIKEN Center for Advanced Photonics, Tohoku University, National Institutes
for Quantum and Radiological Science and Technology, Kyoto University, and Osaka
University have discovered that
terahertz radiation, contradicting conventional belief, can disrupt
proteins in living cells without killing the cells. This finding implies that terahertz
radiation, which was long considered impractical to use, may have applications in
manipulating cell functions for the treatment of cancer, for example, but also that
there may be safety issues to consider..."
IEEE Spectrum / TechInsider is presenting
a free webinar by Zurich Instruments titled "Impedance Analysis: Measuring Low and Fast". It begins at 1:00 am
Eastern Time on Thursday, June 11 (that's today). Drs. Tim Ashworth and Magdalena
Marszalek are the presenters. "Precision, accuracy and measurement speed are three
critical aspects to consider in any impedance measurement. This webinar addresses
all three aspects with two distinct impedance measurement scenarios featuring the
Zurich Instruments MFIA Impedance Analyzer. In the first example, you'll learn how
to use the LabOne User Compensation to measure equivalent series resistance (ESR)
below 1 mΩ and equivalent series inductance (ESL) below 20 nH for
a DC-Link capacitor. You'll also find out how the LabOne Sweeper tool can display
ESR and ESL as a function of frequency, allowing you to see how these values vary
at frequencies other than the test frequency given by the manufacturer..."
Dave Manners has a piece on the Electronics
Weekly website about the 15 most annoying words and phrases used in news and
technical writing, as determined by
The Buzzsaw. Says Dave, "If only marketing gurus realised how
intensely annoying the mindless repetition of some clichéd words are, it would save
us all from a daily dose of Ugh! Thank goodness for www.thebuzzsaw.co.uk which helps
by stripping out these horrors from the turgid rivers of marketing-speak. Here are
the 15 worst offenders with the Buzzsaw judges' comments: The 2020 Buzzsaw Hall
of Shame" Type in your Tweet, e-mail, memo, etc., and Buzzsaw will school you on
which part(s) of the content is(are) annoying to your audience. Examples include
"curated," "disambiguate," "human capital," "in the(this) time of Covid," "going
forward," "we remain cautious," etc.
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 for your military and commercial
communications needs. Sam Benzacar's monthly newsletters address contemporary wireless
subjects. Please visit Anatech today to see how they can help your project succeed.
Here is the final installation of a 22 part
series titled "The Saga of the Vacuum Tube," by Gerald Tyne, that appeared in
Radio News magazine in 1946. Part 1 was printed in March 1943. The collective
contents, which covered the development of the vacuum tube from its conception to
the end of World War I, could have been published as a stand-alone book. Author
Gerald F. J. Tyne presented the series to trace the development which
took place up to the end of World War I along a particular branch of the network
of roads which led to the modern radio tube. He traced the evolution from studies
of the interactions between heat and electricity as pursued by the early philosophers
and by the physicists who followed them (Lee de Forest, et al). These limitations
have been adopted in an attempt to report the work done in the years where there
is a dearth of readily available published material...
Axiom Test Equipment, an electronic test equipment
rental and sales company has published a new blog post titled "Getting Your Lab Equipment Back up and Running" that offers steps
or precautions that should be taken with instruments that have been idle for some
time, which is not unusual during this time of the COVID-19 pandemic, to ensure
that they can provide the most accurate measurements possible as you get back to
work. Since many of us have been working only from home, projects requiring test
equipment have been delayed and the instruments in your lab have been left idle
for a couple of months. Can those instruments be expected to deliver the same levels
of performance and accuracy as soon as they are turned on? Axiom Test Equipment's
latest blog post delves into why it is best to take some quick and easy precautionary
steps...
This could be one of the earliest reports
of
mobile communications between a private automobile and a home
base station. Using a personally designed and installed 5-meter transceiver both
at home and in his car, Mr. Wallace is able to talk to his 12-year-old son
on the way from work. My guess is that in 1935 there were not too many traffic jams,
even in Long Beach, California, so it is doubtful that was the cause for his announced
expected later-than-normal arrival home. The article states the automobile power
supply needed to produce 300 mA of current at 525 V, which is ~160 W
per Ohm's law, which seems unlikely considering car batteries were 6 V at the
time, and that would work out to ~26 A. My question is whether little Billy
possessed a license permitting him to talk back to dear old dad from the home station?
If not, it really doesn't matter at this point since there is probably some statute
of limitations that absolves him from prosecution...
"The U.S. Postal Service (USPS) has temporarily
suspended international mail acceptance for items addressed to certain destinations
due to service impacts related to the COVID-19 pandemic. This situation could result
in the return or loss of mail, such as
QSL cards, addressed to affected parts of the world. The USPS
has posted a list of affected countries, which is updated regularly. The Postal
Service will, upon request, refund postage and fees on mail bearing a customs stamp
that's returned due to the suspension of service, or the sender may re-mail returned
items with existing postage once service has been restored. When re-mailing under
this option, customers should cross out the markings 'Mail Service Suspended - Return
to Sender...'"
RF Cascade Workbook 2018 is the next phase in the evolution
of RF Cafe's long-running series, RF Cascade Workbook. Chances are you
have never used a spreadsheet quite like this. 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...
Res-Net Microwave has a complete line of precision
RF &
microwave components including attenuators, terminations, resistors, and diode
detectors for commercial, military, and space applications. Products range from
the small flange type to large 2,000 watt connectorized power attenuators and/or
terminations at frequencies up to 26.5 GHz. In-house photo etch and laser trim
capability. The company is a leader in development and production of the films required
for these type of RF/microwave components. Please check out Res-Net Microwave's
website to see how they can help with your current project.
This photo of Bell Telephone Labs' three
scientists, G.L. Pearson, D.M. Chapin, and C.S. Fuller, inventors
of the "Bell Solar Battery," reminds me of the very familiar shot of John
Bardeen, Walter Brattain, and William Shockley huddled over their point contact
transistor in December of 1948. The "battery" terminology is an interesting
choice since we normally think of a battery as a charge storage device, but in fact
a battery is fundamentally a charge creation device. A secondary battery may be
recharged by reversing the depleted chemical (or other) process that generated the
initial charge, but it first created the potential via a basic charge separation
process. What we today refer to as a solar cell is a form of primary battery that
is not rechargeable. Just as some chemical batteries (cells) are reactivated by
replenishing the electrolyte, the solar cell is replenished by photons giving up
their energy to the semiconductor substrate...
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As a designated critical industry, ConductRF
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a full line of "ConductRF-D38999-RF-Mixed-Signal-Cables-65-GHz-6-9-2020.htm" target="_top">
D38999, RF and mixed signal cable solutions with performance up to 65 GHz.
D38999 cables are one of our flag ship product capabilities. Standard features include
M85049 backshells, RF contacts for #8, #12 & #16 gauge, BMA & SMPM solutions,
low loss cable types, phase matching available. Custom marking and serialization
also available. Made in the USA. ConductRF coaxial cable assemblies are available
for immediate purchase from
Digi-Key.
"Engineers from NIST have designed a new
method for creating
single-atom transistors that could advance the field of quantum
computing. In conjunction with researchers from the University of Maryland, the
NIST team has successfully created a recipe for designing single-atom transistors.
The step-by-step instructions will allow engineers to fabricate these atomic-scale
devices, which could prove vital in laying the groundwork for quantum computing.
The team from NIST has already made a name for itself in the world of transistors.
It is the second in the world to successfully create a single-atom transistor, and
the first in the world that managed to fabricate single electron transistors that
possess atom-scale control over the geometry of the device..."
Joe Cahak, owner of Sunshine Design Engineering
Services, has submitted another fine article for posting here. Joe has many years
of automated RF testing experience to leverage when writing this paper on the basics
of power measurement. Joe has published many articles here on RF Cafe. This
Ponderings on Power Measurements article begins: "A power measurement
is a scalar quantity and is a measure of power detected. These measurements can
be made a variety of ways. Most of us are familiar with the notion that voltage
(volts) multiplied by current (amps) is power (watts) and power multiplied by time
is energy. At DC or low frequencies these power measurements from the current or
voltage is relatively easy and not very complicated. As we get to higher frequencies
the typical means of measuring voltage or current breakdown and are not accurate..."
Oleksiy Kravchenko has an article posted
on the Electronic Design website entitled, "A Different Twist to Single-Wire Data Transmission." "This
alternative method for a single-wire data-transmission system is designed to handle
a large number of components. Single-wire data transmission is useful when operating
a multitude of disperse components if high speed isn't a requirement, but there's
a need for flexibility. The approach reduces the number of conductors in the cabling
by shrinking size and cost. It can also improve system reliability. Dialog Semiconductor's
GreenPAK is a lower-power, NVM-programmable FPGA that's used in this article to
implement serial-to-parallel converters using a single-wire line. Main idea behind
the method: Let's start with the classic integrating RC element and its properties.
The integrating RC element..."
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!
You genius types might not be able to relate
to the rest of us who read articles like this one titled "Fundamentals of Color TV: The NTSC System" and are in awe of minds
that conjure such things as the NTSC System and then build, refine, and perfect
working hardware. Making the system backward-compatible with existing black and
white (B&W) signals added to the complexity and cleverness of the solution -
akin but more sophisticated than compatibility of stereo with original mono radio
transmissions. When catchy marketing slogans like the familiar (to old folks) RCA
television advertisement claim of "Before you see the color ... Your ColorTrak System
grabs it, aligns it, defines it, sharpens it, tones it ... and locks the color on
track," what it actually means is that a very smart bunch of engineers and scientists
spent a lot of time and money designing...
"A British scientist working in Australia
has found a way to apply a three-dimensional code to a two-dimensional framework
for
quantum error correcting. Government agencies and universities
around the world—not to mention tech giants like IBM, Google, and Microsoft—are
vying to be the first to answer a trillion-dollar quantum question: How can quantum
computers reach their vast potential when they are still unable to consistently
produce results that are reliable and free of errors? Every aspect of these exotic
machines - including their fragility and engineering complexity; their preposterously
sterile, low-temperature operating environment; complicated mathematics; and their
notoriously shy quantum bits..."
With more than 1000
custom-built symbols, this has got to be the most comprehensive set of
Visio Symbols available for RF, analog, and digital system and schematic
drawings! Every object has been built to fit proportionally on the provided
A-, B- and C-size drawing page templates (or can use your own). Symbols are provided
for equipment racks and test equipment, system block diagrams, conceptual drawings,
and schematics. Unlike previous versions, these are NOT Stencils, but instead are
all contained on tabbed pages within a single Visio document. That puts everything
in front of you in its full glory. Just copy and paste what you need on your drawing.
The file format is XML so everything plays nicely with Visio 2013 and later...
Somebody get Al Gore on the phone - preferably
using Skype. It appears that maybe he did not invent the Internet after all. Sci-fi
writer William F. Jenkins, who went by the pen name "Murray Leinster," wrote
a short story entitled A Logic Named Joe, that appeared in March 1946 issue of Astounding
Science Fiction. In the story, an amazingly prescient description of the modern
Internet is laid out. The works is copyrighted so I will not replicate the entire
thing here, but these are a few excerpts that sound a lot like Mr. Leinster was
in cahoots with DARPA during the development*. Before I forget, thanks to RF Cafe
visitor Terry W. for sending the link. My comments look like...
"In early September 2019, a radical environmentalist
group called 'Heathrow Pause' threatened to shut down Heathrow Airport in the UK
by flying drones within the airport's no-fly zone to call attention to climate change.
Some Heathrow Pause members were arrested the day before their previously announced
fly-date (9/13) and on the day itself their drones were unable to take off, electronically
jammed by the authorities. The protest represents a new wrinkle in the fast-moving
world of
unmanned aircraft systems (UAS) use and integration. As previous
drone-induced airport disruptions at Heathrow and Gatwick in the UK and at Newark
Airport, New Jersey in the U.S. demonstrate, society will need to prevent as well
as facilitate drone use in daily life..."
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.
Each week, for the
sake of all avid cruciverbalists amongst us, I create a new
technology-themed crossword puzzle using only words from my custom-created
lexicon related to engineering, science, mathematics, chemistry, physics, astronomy,
etc. 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,
see someone or something in the exclusion list who or that is directly related to
this puzzle's theme, such as Hedy Lamarr or the Bikini Atoll, respectively. Enjoy!
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. Some quoted items have been shortened
to save space. About RF Cafe.
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