See Page 1 |
2 |
3 |
4 of the March 2021 homepage
archives.
Sunday the 14th
This
Science-Theme Crossword Puzzle for March 14th has many words and
clues related to... you guessed it... RF engineering - and mathematics, chemistry,
physics, and other technical words. As always, this crossword contains no names
of politicians, mountain ranges, exotic foods or plants, movie stars, or anything
of the sort unless it/he/she is related to this puzzle's technology theme (e.g.,
Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst
us will appreciate the effort. Enjoy!
Friday the 12th
Today's
ceramic capacitors are vastly different from most of those from
the middle of the last century. While the ceramic capacitor in your modern electronic
circuit is likely in the form of a thin circular or rectangular package, or of a
tiny surface mount outline, those described in this Radio-Electronics magazine
article were rather large tubular devices that had the appearance of a wirewound
power resistor. The advantages of ceramic capacitors over other types available
in the 1950 (paper and mica) are basically the same as today - high voltage handling
and tight tolerances of down to ±1%. Table I lays out a comparison. Wikipedia
has an extensive comparison of modern capacitor types, illustrating how far technology
has advanced since then...
"When Kevin Wells's private jet lost its
GPS reception on the approach to Hayward Executive Airport in California's Bay Area
in February 2019, he whipped out his phone and started filming the instrument panel.
For a few seconds, the signals from over a dozen GPS satellites can be seen to blink
off, before slowly returning as Wells continues his descent and eventually makes
a safe landing. Wells was quick to film the incident because this was not the first
time he had suffered GPS problems. Less than a month earlier, his Cessna had been
hit by a similar outage, at almost the identical location. 'At that point it was
pretty clear to me that it was either inadvertent or purposeful jamming,' he told
IEEE Spectrum. 'And I wanted to track it down.' Wells had fallen victim to
GPS interference events..."
If terms like "magnetostriction," "mu-metal,"
and "D-ring" arouse your technostimulus receptors, then this quiz on
Magnetic Phenomena should be just what you've been waiting for.
It appeared in a 1962 edition of Popular Electronics, but the principles
therein have not changed since then. I must admit that I had never given thought
to the orientation in which bar magnets should be stored when in close proximity
to each other, especially since trying to store them the "wrong" way results in
them trying to reconfigure themselves to the "right" way automatically. Not mentioned
here is that a soft iron or other ferrous metal should be placed across the ends
to help concentrate the magnetic fields within the magnets, thereby reducing the
possibility of demagnetization due...
PCBONLINE supplies complex rigid and flex-rigid
printed circuit
boards (PCBs),and one-stop production with maximum flexibility ranging from
prototype sample to mass production. Rigid-flex, HDI, multilayer, IC-loadboard,
LCP 5G optical module, ceramic, MCPCB. Materials include Rogers, Taconic, Arlon,
Isola, Bergquist, Kapton, Panasonic, and more. After more than 15 years of continuous
efforts, PCBONLINE constantly updates our equipment, improves our technology, and
serves you with the highest quality. Cost and delivery quotations online without
the need for multiple phone call and/or e-mails.
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. Two new filters have been introduced: A surface mounted
LTE 1542 MHz /1643 MHz L-Band Ceramic Duplexer having a bandwidth of 34 MHz
(±17 MHz) in both bands with 50 dB isolation between bands, and a 5500
MHz Suspended Substrate Highpass Filter with rejection of 60 dB from DC
to 4950 MHz at up to 15 watts. Custom RF power directional coupler designs
can be designed and produced when a standard cannot be found, or the requirements
are such that a custom approach is necessary...
Nova Microwave is a leader in technically
differentiated electronic and radio frequency Ferrite
Circulators
and Isolators that connect, protect and control critical commercial and military
wireless telecommunications systems. Our staff is dedicated to research and development
of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz
to 26.5 GHz. Available in single or multi-junction topographies, the Nova Microwave
product line of is specifically designed for use in varied environmental and temperature
extremes.
Thursday the 11th
Here's a good article for the train lovers
out there (there are many). According to an article I found in the Allentown
Morning Call, the world's first
radio broadcast from a moving train took place on Sunday, March
27, 1932. The feat was accomplished by radio station WJZ out of New Jersey, while
aboard a Baltimore and Ohio (B&O) train. As reported in Radio News
magazine a decade later, radio was being used for reliable communications between
not only the attached cars (which also often had some wired interconnections), but
between other trains and between the train and depots and switch yards. Given the
era, no doubt the accomplishment relied at least partly on technology developed
during World War II. Radio facsimile allowed printed messaging to replace the
previous method of using a hook to snatch...
Every angle is covered now for anyone needing
high quality, professional-looking
graphical
shapes for creating block diagrams, schematics, and test setups. I spent hundreds
of hours creating these formats to play well with Visio, Word, Excel, and Power
Point. All versions' components can be broken into constituent parts for editing,
and can be re-sized without pixelation. Page Templates with border and title block
are provided as well. At $35 each (or all 3 for the price of 2), the cost is easily
justified. Site Licenses available. Your support will be greatly appreciated.
"Researchers at the U.S. Naval Research Laboratory
(NRL) integrated an accurate and efficient model of nuclear fission into a new software
suite to give users a powerful and flexible tool to quickly and accurately model
new and highly complex nuclear detection scenarios.
SoftWare for Optimization of Radiation Detectors (SWORD) is an
integrated software package that offers an interface to radiation transport codes,
allowing users to design and optimize radiation detectors, which results in the
faster development and evaluation of radiation detection equipment. 'Our sponsors
and end users are focused on preventing nuclear weapons and other radiological devices
from being smuggled..."
Since 2003, Bittele Electronics has consistently
provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly
services. It specializes in board level turnkey
PCB assembly
for design engineers needing low volume or prototype multi-layer printed circuit
boards. Free Passive Components: Bittele
Electronics is taking one further step in its commitment of offering the best service
to clients of its PCB assembly business. Bittele is now offering common passive
components to its clients FREE of Charge.
This might be the first (and only) appearance
of Carl's father, at least in a drawing. In this episode, John T. Frye's high-tech
teen duo Carl and Jerry design and build a "polecat detector." In the process, a
little drama is thrown in when a stander-by mistakenly believes he is being insulted.
Even if, in spite of the detailed description by Jerry, you don't learn how a photocell-based
threshold crossing circuit works, you might just learn the meaning of 'lugubriously.'
Mr. Frye always worked valuable technical information into his stories about
"Carl & Jerry," "Mac's Service Shop," and other regular features which appeared
in electronics magazines for decades.
The Engineer website just published
a very extensive
UK Engineer Salary Survey 2020/21. Cutting to the chase, the average
salary of 845 respondents was £56,807. Oil & gas engineers toped the list
at £75,366, while telecomms / utilities / electronics (TUE) got 3rd place at £58,412.
British citizens who worked outside the country trumped every other category with
a peak of £147,168. Scotland, Wales and Northern Ireland electronics engineers averaged
£105,539 while South West (England) earned only £43,250. TUE's over 50 years of
age constitute 61% of their category, and under 35 years old is just 12%. That looks
like an excuse to massively import foreigners to fill the looming gap. Roughly half
of TUE's like their jobs and a third like their salary. Half want a new job and
half feel valued in their job.
Read the report...
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. Fast turn-around on quotations for PCB fabrication and assembly.
Wednesday the 10th
"Mediocre and half-baked technicians will be just out of luck."
So said Radio-Craft editor Hugo Gernsback, writing in the January 1945
issue about the opportunities likely to be awaiting radioservicemen. Surprisingly,
at least to me - but I suspect also to most of his readers at the time - Mr. Gernsback
predicted that the majority of post-war electronics technician jobs will be for
other than the kind of radio service work that existed before World War II.
Major advances in factory automation with both electrical and mechanical innovations,
when combined with recent advertising by consumer product manufacturers promising
all sorts of amazing home appliances and entertainment gizmos, will assure a much
wider and deeper (technically) variety of service work. Commercial, industrial,
and domestic was predicted to require more troubleshooting, repair and maintenance
savvy than merely swapping out vacuum tubes or tweaking potentiometers until "it
seems right." Hence, the opening comment...
Modelithics announces the release of the
newest version, version 21.0, of the Modelithics COMPLETE Library for use with
Keysight Technologies' PathWave Advanced Design System (ADS) software
platform. The new release includes compatibility with PathWave ADS 2021 Update 2
as well as 10 new models representing over 220 components. The Modelithics COMPLETE
Library contains over 775 highly scalable Microwave Global Models™ representing
over 22,000 passive and active components. The library is an indispensable collection
of simulation models for all types of passive and active RF & microwave devices
engineered to enable designers to go from concept to product faster and easier.
These models for discrete die, surface mount...
"Experts at the U.S. Naval Research Laboratory
have created and tested
3D-printed antennas and arrays to advance radar technology and
enable new applications for the U.S. Navy. The lightweight and rapid production
of 3D-printed parts make it an attractive alternative to traditional manufacturing
that often requires expensive materials and specialized equipment. 3D printing is
a way to produce rapid prototypes and get through multiple design iterations very
quickly, with minimal cost. Radar systems perform critical functions for the Navy
and remain an important part of maritime navigation and national defense. Parts
for antennas and arrays, which are multiple connected antennas working together..."
Per Wikipedia, "A
selenium rectifier is a type of metal rectifier, invented in 1933.
They were used to replace vacuum tube rectifiers in power supplies for electronic
equipment, and in high current battery charger applications. The photoelectric and
rectifying properties of selenium were observed by C. E. Fitts around 1886 but practical
rectifier devices were not manufactured routinely until the 1930s. Compared with
the earlier copper oxide rectifier, the selenium cell could withstand higher voltage
but at a lower current capacity per unit area." Electronics magazines of the era
published many articles about selenium rectifiers...
ConductRF
hand-formable RF coaxial cables are available off the shelf from
Digi-Key. ConductRF FM series of Hand Formable RF cable assemblies provides system
designers with a versatile solution that allows RF cables to be physically routed
and set in to position during installation. Standard lengths and connector types
feature performance up to 18 GHz. Low loss, tinned braided cable of 0.086"
diameter with shielding of >100 dB. 100% factory tested for VSWR & insertion
loss. RoHS & Reach compliant. Ideal for internal module linking and great
for RF Testing. When compared to traditional semi-rigid options, these cables can
provide increased installation flexibility at a substantially lower cost. Made in
the USA!
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 the 9th
As with most new discoveries, advancements
came quickly with
transistors. A little more than six years after Messrs. Brattain,
Shockley, and Bardeen announced their invention of a positive gain, point contact
transistor, this article in Radio-Electronics magazine reports on the wonders
of junction diodes and transistors that eliminate the mechanical interface of the
"cat's whisker" that was vulnerable to failure due to shock, vibration, and temperature
changes. Note how closely spaced the patent numbers mentioned are for Sidney Darlington's
compound transistor (aka a Darlington pair), Shockley's bistable transistor oscillator,
Gordon Raisbeck's NPN-PNP balanced pair amplifier, and Robert Blakely's 3-terminal
transistor mixer. Bell Labs, IBM, and the other big name research companies and
universities...
Qorvo®, a leading provider of innovative
RF solutions that connect the world, is proud to have been an integral part of the
Mars Perseverance 2020 Mission that successfully landed an unmanned
rover on Mars on February 18, 2021. NASA's Jet Propulsion Laboratory (JPL) officials
confirmed that Qorvo products were integrated into the Mars Perseverance's critical
descent stage landing radar. This mission-critical radar guides the rocket-powered
"backpack" that helped the Perseverance Rover land safely on the surface of Mars.
James Klein, president of the Infrastructure and Defense Products (IDP) business,
said, "The Qorvo team is proud to support this historic scientific mission. Mars
Perseverance proves that the products we design, manufacture and test can perform
flawlessly, even under the harshest environmental conditions...
"The team from the Intelligent Vehicles Group
at Warwick University published its study in the IEEE Sensors Journal, which details
how the researchers specifically simulated and evaluated the performance of
LiDAR sensors in the rain. High-level autonomous vehicles (AVs)
are promised by Original Equipment Manufacturers (OEMs) and technology companies
to improve road safety as well as bringing economical and societal benefits. All
high-level AVs rely heavily on sensors to operate. Using the WMG 3xD simulator,
researchers tested an autonomous vehicle's LiDAR sensors in different intensities
of rain..."
An article with instructions relating to
subjects like overthrow, balance, friction, and cleaning could very well be about
a country's revolutionary struggles. In this case, it is an article about how to
rejuvenate a persnickety or inaccurate mechanical (aka analog)
meter movement. W.R. Triplett, relative (I assume) of meter manufacturer Ray L.
Triplett, is the author (Triplett is now owned by Jewel Instruments). There are
a lot of analog meters around in labs, workshops, and garages. Unless they have
been burnt out, most probably still work like new. Occasionally, however, the movements
get sticky because of accumulations of dirt and dust, bug filth, or even from corrosion.
This article offers some great tips for making them serviceable again...
Modelithics, Inc. is seeking Senior RF Test Engineer
who is experienced with RF testing, RF / microwave lab equipment and lab software
as well as having experience with I-V measurements / transistor linear and nonlinear
measurements, particularly high-power load pull. Must have the ability to efficiently
multi-task in a high paced, rapidly changing environment. Primary duties are to
develop, manage assembly and execution of test plans for multiple customer projects.
Additional responsibilities include managing the receipt and inventory of customer
DUTs and other project related components. Additional duties may include data analysis
and review, generating test data reports, develop / design models of calibration
standards, analyze / assess calibration quality as well as support the modeling
engineers and engineering team. Additional assistance may include training...
Joel Brand has an interesting article on
the IEEE Spectrum website entitled, "How To Build a Radio That Ignores Its Own Transmissions." In it
he discusses self-interference inherent in most star networks. Mr. Brand begins:
"Wireless isn't actually ubiquitous. We've all seen the effects: Calls are dropped
and Web pages sometimes take forever to load. One of the most fundamental reasons
why such holes in our coverage occur is that wireless networks today are overwhelmingly
configured as star networks. This means there's a centrally located piece of infrastructure,
such as a cell tower or a router, that communicates with all of the mobile devices
around it in a starburst pattern. Ubiquitous wireless coverage will happen only
when a different type of network, the mesh network, enhances these star networks.
Unlike a star network, a mesh network consists of nodes that communicate with one
another as well as end-user devices. With such a system, coverage holes in a wireless
network can be filled by simply adding a node..."
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.
Monday the 8th
One of the great benefits of buying and reading
these vintage electronics (and other types) magazines is running across information
you have read or heard about from a historical perspective, but was late-breaking
contemporary news at the time of publication. Although I cannot cite a specific
instance off the top of my head, there have been times when the original sources
told a very different story than the one often heard in second-, third-, or fourth-hand
versions far removed from the actual event. It is like a Xerox copy of a document
that has been through many iterations of copies of copies of copies. This 1954 issue
of Radio-Electronics magazine reports on a petition submitted to the FCC
by none other than Senator Joseph McCarthy, seeking to require all radio stations,
including those of amateur operators...
It's not quite as monumental a find as discovering
the Dead Sea Scrolls in a cave, or an original showroom-new Ford Model T sitting
in a barn, but what Martin H. came upon in the attic of a old house in Gorlitz,
Germany, definitely rates an "amazing!" response. Sitting on the Polish border,
previously owned by an East German policeman, the domicile contained one each of
the following pieces of vintage Rhode & Schwarz test equipment in brand new
condition: • R&S Resonance Frequency Meter, Type WAM, BN 4312/2
(ca 1968) • R&S Phase Meter, Type PZN, BN 1941 (ca 1965)
• R&S Power Signal Generator, Type SMLM, BM 4105 (ca 1974). Martin
is looking for a buyer for all three of these magnificently preserved pieces of
electronics history. The photos show no sign of damage, contamination or fading...
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!
"Electrical and Electronic Equipment (EEE)
has become indispensable in modern societies and is enhancing living standards,
but its production and usage can be resource-demanding. After its use, EEE is disposed
of, generating an
e-waste stream that contains hazardous and valuable materials.
EEE includes a wide range of products with circuitry or electrical components with
a power or battery supply, according to The Global E-Waste Monitor, a report produced
annually by United Nations University and other international organizations..."
"There's a WAR to be won." So goes the headline
in an advertisement in the April 1942 edition of QST magazine. Like many
American companies during World War II,
Cardwell Manufacturing Corporation gave its highest priority to
serving the needs of our nation's military. Patriotism was actually taught in schools
back in the day, and the majority of citizens understood the need to devote their
efforts to achieving victory, even if it meant putting personal interests on hold.
The ad content typifies that attitude: "Though all our facilities of men and machines
have long been pledged to the fulfillment of our assigned tasks, and though hundreds
of thousands of Cardwell components are in active service on the far flung battlefronts
of the United Nations, many times this effort is needed. And so, to our loyal personnel,
we are saying, 'Let's redouble production again..."
How come nobody told me about this? With
all the articles I've read about the Perseverance rover recently landed on Mars,
none come to mind which mentioned a
message on the underside of the parachute used to lower the atmospheric
entry spacecraft and its load to the point where retrorockets took over just above
the surface. It only took a moment to figure it all out - much simpler than Carl
Sagan's team's cryptic message on the
Pioneer 10
and 11 interplanetary explorers, but a bit more tricky than "We come in peace for
all mankind" on Apollo 11's Eagle lunar module. Très cool, IMHO.
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.
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. I also
have an extensive list of
Recently Added topics.
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)
|