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4 of the April 2022 homepage archives.
Thursday the 7th
"The year 1950 will be recorded historically
as the year the microwave relay made its impact felt." That was the closing sentence
by Philco Sales Engineer Leo Sands in his 1950 Radio & Television News
magazine article entitled, "The
Microwave Era Begins." Mr. Sands was not suggesting that it was the start
of the widespread use of microwaves in general, but specifically the use of microwaves
for long distance, broadband transmission of telecommunications signals. 1950 is
about the time microwave relay stations began appearing on hilltops and rooftops
of tall buildings all across the land, with the goal of replacing coaxial lines
which needed to be strung or buried from end to end. Great cost is associated with
a hardline approach for acquisition of land rights, installation, and maintenance.
Yes, those kinds of expenses are required for microwave relay stations, too, but
in the long run they tend to be much lower, and the service much more reliable and
"upgradable." Lots of people opposed the installation of the unsightly, behemoth
towers, and many people expressed concern over exposure to microwave energy. If
only they knew then how miniscule their worries were compared to today's situation
with cell towers within eyeshot of just about ever locations on earth...
"From MRI machines to computer hard disk
storage, magnetism has played a role in pivotal discoveries that reshape our society.
In the new field of quantum computing, magnetic interactions could play a role in
relaying quantum information. In new research from the U.S. DOE's Argonne National
Laboratory, scientists have achieved efficient quantum coupling between two distant
magnetic devices, which can host a certain type of
magnetic excitations called magnons. These excitations happen when an electric
current generates a magnetic field. Coupling allows magnons to exchange energy and
information. This kind of coupling may be useful for creating new quantum information
technology devices. 'Remote coupling of magnons is the first step, or almost a prerequisite,
for doing quantum work with magnetic systems,' said Argonne senior scientist Valentine
Novosad, an author of the study..."
I have to admit to not recalling ever having
heard of Dagmar; have you? Crack electronics technician "Red" mentioned her in this
episode of "Mac's
Radio Service Shop" appearing in the March 1952 edition of Radio & Television
News. I thought Prince and Cher were the first man (ostensibly) and woman,
respectively, to use a single-name public moniker, but evidently Dagmar beat them
to the punch ...but I digress. John T. Frye, author of the popular Carl &
Jerry series that appeared later in Popular Electronics magazine, wrote
this series before that time. On this cold and wintry day, Red and Mac are discussing
troubleshooting methods and how looking for and interpreting certain symptoms can
lead to speedy and successful diagnosis and repair. Today's repair shops are mostly
changing cracked cellphone LCDs or replacing laptop computer keyboards that have
had soda or beer spilled on them, so elaborate technical skills are not needed as
much - just a deft touch and steady hands...
Modelithics just sent out their
April New Products Blast, which includes a new Modelithics 3D Brick Model™ for
Würth Elektronik's WCAP-CSRF 0402 (NP0) series capacitor, Modelithics models for
Coilcraft's 0603CT and 0603HL series inductors, more than 150 Mini-Circuits models,
and Modelithics models are available now for the Passive Plus® R35-1209BB and R35-2010BB
series. Modelithics is pleased to announce our newest offering of Test Fixtures
and Test Accessory products, including legacy parts from J MicroTechnology for a
family of thin film Alumina substrate components to adapt the benefits of coplanar
waveguide wafer probe test methods to the measurement of devices suited for connection
to microstrip circuits. Along with this offering Modelithics is also offering custom
coaxial and RF probe test fixtures suited for a wide range of substrate and test
interface environments...
Fortunately, there is a constant flow of
people newly interested in electronics who are seeking information on basic principles.
Some will find an article this one on
Ohm's law fundamentals and decide maybe being just a user of electronics is
good enough. Others will, as did you and I, read this kind of material and be amazed
at how ultimately predictable electrical circuit parameters are. If he or she continues
and launches into a career in electronics or electrical engineering, it won't be
long before he or she will, as do you and I now, look back at how simple things
were at the beginning of the journey ;-) This 1956 Popular Electronics magazine
article was written half a century ago, but to a word everything contained herein
is as valid today as it was then...
RF Cascade Workbook 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 (click here for screen capture). 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...
Berkeley Nucleonics Corporation (BNC) is
a leading manufacturer of precision electronic instrumentation for test, measurement,
and nuclear research. Founded in 1963, BNC initially developed custom pulse generators.
We became known for meeting the most stringent requirements for high precision and
stability, and for producing instruments of unsurpassed reliability and performance.
We continue to maintain a leadership position as a developer of custom pulse, signal,
light, and function generators. Our designs incorporate the latest innovations in
software and hardware engineering, surface mount production, and automated testing
procedures.
Wednesday the 6th
Radio-Electronics magazine's November
1959 issue had a few interesting tidbits in the News Briefs section. The first is
a note about Major Edwin Armstrong's estate having won a patent infringement case
against the Emerson Radio & Phonograph Co. Maybe he wouldn't have committed
suicide by jumping out a window if he hadn't had to fight so many IP (intellectual
property) battles in his lifetime. Interestingly, the news also mentions that he
received more than $5 million in royalties for his FM radio patents. Another item
of note is the introduction of
secondary radar (aka IFF, identification friend or foe, in military terminology).
IFF is not a passive reflected signal system, but uses a transponder in the aircraft
to reply to the received signal on an offset frequency. The reply can include parametric
information about the aircraft such as altitude, a unique identification (squawk)
number, etc. It is a significant enhancement to primary radar, particularly in crowed
environments...
Call me a hopeless
nostalgist when it comes to favored institutions I grew up with. I miss Pontiac
dealerships, Montgomery Ward, and Radio Shack stores. I miss Uncle Ben on the converted
rice package, and the indian squaw on the Land O'Lakes margarine package. I miss
trips to Blockbuster Video stores on Saturday to pick up a movie on VHS tape, and
walking through Toys R Us during the Christmas season. General Foods, Woolworth,
Eastern Airlines, Circuit City, Western Auto, Drug Fair, Read's Drug, Britt's Department
Stores, Lafayette Radio, A&P Grocery, Northern Reflections, Hechinger Home Improvement,
and Babbage's Software. All those and more were part of my growing up in the Annapolis,
Maryland area (with Parole Plaza being the prime shopping complex in the era). One
of the things I miss the most is the old
Sear, Roebuck and Co. stores - particularly the Craftsman tools and lawn and
garden sections. My parents bought just about everything from Sears, from us kids'
(five of us) school clothing, to household appliances, to lawn mowers, to furniture.
Sears' Open Hearth sofas, chairs, end tables, etc. (pretty sure we had this), were
nice wood and cloth designs which wore well and were fairly inexpensive. Of course
the Sears Wish Book and Montgomery Ward Christmas catalogs...
Altum RF, a supplier of high-performance
RF to millimeter-wave semiconductor solutions for next generation markets and applications,
announces three new
GaAs pHEMT MMIC amplifiers targeting applications covering Q, V, and E-bands.
Using WIN Semiconductors' next-generation PP10-20 GaAs pHEMT technology, these compact
die amplifiers achieve high gain and low noise, while simplifying design-in for
engineers by using single gate and single drain supplies. ARF1208 low noise amplifier
- 37-59 GHz, 2.5 dB noise figure and 26.5 dB linear gain (ARF1207
57-71 GHz, ARF1206 71-86 GHz). WIN's PP10-20 technology builds on the
proven and mature PP10-10 platform and targets applications up to 170 GHz.
As a key differentiator, PP10-20 allows for a substantial increase in gain, with
the same operating voltage for power applications. Building on our experience with
WIN's proven 0.1 μm technology and with careful attention to modeling, design
and simulation workflow, we achieved first-pass success with a family of millimeter-wave
products...
A good primer on the physics behind and
use of
thermistors was published in the November 1956 edition of Popular Electronics.
Thermistors are fundamentally substances that exhibit a large change in resistance
for a given change in temperature, called temperature coefficient of resistance
(TCR, or RT). Standard resistors would ideally maintain the exact same resistance
regardless of temperature, but in reality most resistor types increase in resistance
with an increase in temperature; i.e., a positive TCR. Most thermistors have a negative
TCR, which makes them useful for cancelling out resistor temperature sensitivity.
Thermistors are also used for temperature sensing and measurement, although thermocouples
generally do a much better job for that application...
Axiom Test Equipment, an electronic test
equipment rental and sales company has published a new blog post entitled "Semiconductor
Measurements Characterize Devices and Materials" that informs people on how
semiconductor testing can be conducted. Semiconductors are essential to modern electronics
and can be found in almost all electrical products throughout many industries. They
come in many forms, with diodes, optocouplers, rectifiers, and transistors among
discrete devices. Because semiconductor testing covers such a variety of devices
under test (DUTs), it involves many different measurements and, depending on the
DUT, often many different test units to perform the measurements. Gaining a better
understanding of a semiconductor or the material it is fabricated on requires evaluating
it under different operating conditions, such as different voltage (V), current
(I), and power levels. In some cases, testing...
Electrolytic capacitors have long been the
components that provide the highest capacitance density factor, that is, they have
the highest capacitance value for a given volume of space occupied. Anyone familiar
with electrolytic capacitors is aware of the polarization indicated on the package
(a marking or unique physical feature), indicating that there is required direction
for hookup; in fact, a backwards connection can lead to an explosive failure. Yes,
I know there are now unpolarized electrolytic capacitors available. While physical
construction of electrolytic capacitors have evolved over the decades since this
article was published in a 1930 issue of Radio-Craft magazine, the fundamental
operation has not. It is interesting to note the reference to capacitors as "condensers,"
a name still commonly used with internal combustion engine ignition systems and
with some AC motors that use them at turn-on for providing a starting coil phase
shift. Also used here is the term "valve" when referencing the diode...
It was a lot of work, but I finally finished
a version of the "RF & Electronics Schematic & Block Diagram Symbols" that
works well with Microsoft Office™ programs Word™, Excel™, and Power Point™.
This is an equivalent of the extensive set of amplifier, mixer, filter, switch,
connector, waveguide, digital, analog, antenna, and other commonly used symbols
for system block diagrams and schematics created for Visio™. Each of the 1,000 or
so symbols was exported individually from Visio in the EMF file format, then imported
into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or
down without becoming pixelated, so all the shapes can be resized in a document
and still look good. The imported symbols can also be UnGrouped into their original
constituent parts for editing. Check them out!
LadyBug Technologies was founded in 2004
by two microwave engineers with a passion for quality microwave test instrumentation.
Our employees offer many years experience in the design and manufacture of the worlds
best vector network analyzers, spectrum analyzers, power meters and associated components.
The management team has additional experience in optical power testing, military
radar and a variety of programming environments including LabVIEW, VEE and other
languages often used in programmatic systems. Extensive experience in a broad spectrum
of demanding measurement applications. You can be assured that our Power Sensors
are designed, built, tested and calibrated without compromise.
Tuesday the 5th
I was very surprised to find an example of
a rather significant flexible printed circuit substrate in this "Printed
Circuits Are Here to Stay," article appearing in a 1959 issue of Radio-Electronics
magazine. That era was when much debate, particularly amongst service people, was
occurring regarding whether printed circuits would be a welcome replacement for
the previous point-to-point wiring method of connecting components and cables. Proponents
appreciated the neatness and compactness, while opponents didn't like the lack of
robustness and intolerance to heating and pulling off mounted components. What was
even more interesting was the mention of a "Persister" element, that was made by
Ramo-Wooldridge - the "RW" part of "TRW" (Thompson Ramo Wooldridge, which merged
in 1958). A Web search on persister turns up only biological cells which resist
antimicrobial treatments...
Exodus Advanced Communications, a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide, announces their model
AMP2033LC is designed for replacing aging TWT technology. The AMP2033LC is a
broadband, rugged EMC Class A/AB linear design for all modulations and industry
standards covering 6.0-18.0 GHz. It produces >100 W minimum, with a
50 W P1dB, and a minimum 50 dB of gain. Excellent flatness, optional monitoring
parameters for forward/reflected power, VSWR, voltage, current & temperature
sensing for superb reliability. Exodus Quiet-Cool technology is featured in our
compact 5U chassis weighing a nominal 75 lbs...
If you think the controversy over whether
drivers being distracted by telecommunications devices is something new, consider
this article from a 1935 issue of Radio-Craft magazine. Mobile radio was
a relatively new possibility at the time, as was the horseless carriage into which
installation was a cause for concern by insurance companies and government regulators.
Just as nowadays we worry about and sometimes fining drivers who use a smartphone
for texting while driving, the state of Connecticut in 1935 went so far as to propose
imposing a fine of $50 ($1035 in 2022 money) for installing a radio set or any "other
device which tends to distract the attention" of the operator...
"A microstructure created by a 3D printer:
the innovative refractive structure developed by PSI scientists and which combined
with a diffractive element, results in an
achromatic X-ray lens, is almost a millimeter long (or high, as shown in the
photo). Turned on its end, it resembles a miniature rocket. It was created by a
3D printer using a special type of polymer. This image of the structure was captured
using a scanning electron microscope. Paul Scherrer Institute scientists have developed
a groundbreaking achromatic lens for X-rays. This allows the X-ray beams to be accurately
focused on a single point even if they have different wavelengths. The new lens
will make it much easier to study nanostructures using X-rays, according to a paper
just published by the researchers in the scientific journal Nature Communications..."
thinkRF has an opportunity for
Senior RF Engineers
who can provide technical leadership and innovative support for the next stage in
our company's growth. We're looking for people who want to disrupt RF monitoring.
We're an ambitious, diverse, closely knit team of RF experts who are driven to redefine
how 5G wireless spectrum is monitored and managed. In this role, you would be responsible
for the design, simulation, development, and testing of RF circuits and systems
for application in wideband radio receivers spanning from DC all the way up to mm
wave. You will hold the primary engineering responsibility for electrical design
tasks including requirements analysis, specification generation, interface definition,
component selection, circuit simulation, symbol creation, schematic capture, and
board layout. As the Senior RF Engineer, you will own schedules, cost, and have
technical responsibility at the board or subsystem level...
"What's the big deal about a night vision
scope for your rifle?," you might ask, since I can buy an
infrared scope for my rifle on Amazon for under $500. The answer is that no,
it is not a big deal now, but in the 1940s while it was being developed and deployed
for the military, it was Top Secret. Just as radar is a yawn in any discussion of
leading edge technology today, it was vital to keeping the free world free. It wasn't
until after World War II had ended that infrared scopes found their way into
unclassified articles, but even then the cost was way more than any non-governmental
entity could afford. The Night Owl Optics NightShot Digital Night Vision Riflescope
from Amazon is not a top-end product, but chances are that being all solid state
it performs at least as well as the beast shown in this article and is much more
rugged than the vacuum tube based 1940s design. Note that the Army guy is wearing
a backpack just to hold the battery...
New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website visits each weekday.
RF Cafe is a favorite
of engineers, technicians, hobbyists, and students all over the world. With more
than 12,000 pages in the Google search index, RF Cafe returns in favorable
positions on many types of key searches, both for text and images. New content is
added on a daily basis, which keeps the major search engines interested enough to
spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. I also re-broadcast homepage
items on LinkedIn. If you need your company news to be seen, RF Cafe is the
place to be.
KR Electronics designs and manufactures
high quality filters for both the commercial and military markets. KR Electronics'
line of filters
includes lowpass, highpass, bandpass, bandstop and individually synthesized filters
for special applications - both commercial and military. State of the art computer
synthesis, analysis and test methods are used to meet the most challenging specifications.
All common connector types and package form factors are available. Please visit
their website today to see how they might be of assistance. Products are designed
and manufactured in the USA.
Monday the 4th
This data sheet with schematic and aligning
procedures for the
Garod model 6AU-1 tabletop radio appeared in the November 1946 issue of
Radio-Craft magazine. It was AM only (shortwave and FM were not in use yet),
and operated off of batteries (DC) or the AC line. It was one of the earlier radio
to use a Bakelite-like phenol formaldehyde resin material for the cabinet rather
than the more traditional wood. Molded plastic was not yet a thing in high volume
commercial production. The brown (or bright red) and gold motif was considered avant-garde
(aka Art Deco) compared to the more conservative solid and wood laminate finishes.
There was also a version with orange case and red grille. The overall size was 11"
wide x 6.5" high x 6" deep. There are many finely restored exampled around the Internet...
I
have been following the progress of NASA's new Artemis heavy lift rocket, designed
to be bigger and better than the Apollo era
Saturn V booster. Not
needing to hitch rides on Russian and Chinese rockets anymore would be nice. The
agency's "Artemis
I Launch Countdown 101" page defines and details some of the terminology and
schedule items, including the pre-launch timeline. It includes not only the familiar
"T-minus..." countdown benchmarks but also the "L-minus" (L being launch) milestones.
The very first item in the "L-minus" as of this writing says, "L-45 hours and counting:
The launch team arrives on their stations and the countdown begins (L-45, 40
minutes hours)." That should be "(L-45 hours, 40 minutes)," a la the
other items in the list. You might recall the spectacular and sickening crash of
NASA's
Mars
Climate Orbiter into the red planet in 1999. A simple lack of proper conversion
from metric to SI units was identified as the culprit. I look forward to the return
of a U.S. capability of launching manned missions again (dead since the
Space Shuttle program
shut-down in 2011), and certainly hope such a lack of attention to details will
not doom it from the start (or maybe the L-45 hours, 40 minutes point). Oh, and
there's also a misspelling on the page (coundown vs. countdown). The devil is in
the details, as the saying goes.
Carl and Jerry were early adopters of the
near field communications (NFC) craze that is going full-swing today. As they often
do, the harmlessly mischievous teenage duo used their combined grasp of modern electronics
to pull off gags on unsuspecting friends ... and sometime adversaries. In this episode,
a near-field transmitter and receiver pair is designed to help Carl bedazzle a scientist
who was attempting to disprove the ability to use "Extrasensory Perception" (ESP)
- the title of this 1956 Popular Electronics magazine technodrama - to determining
what another person was thinking about. In this case it was detecting which playing
card was being displayed on an overhead projector. Of course Carl didn't really
have "the gift," but relied on his co-conspirator, Jerry...
In a Scientific American article
titled "Elemental
Urgency," Jennifer Hackett reported on a paper published in 2013 by Yale University's
Thomas Graedel et al regarding the availability (or unavailability) of the raw elements
- and suitable substitutes - used extensively in modern manufacturing. Unlike half
a century ago when most products were made from relatively common and easily obtainable
elements like lead, iron, tin, nickel, aluminum, carbon, zinc, silicon, and even
silver and gold, many more elements are now regularly included in mass manufacturing
processes. Rhenium (Re), used in high strength, temperature alloys to applications
like jet engine turbine blades and as a catalyst in chemical processes, is one of
the most critically rated elements for uniqueness. Ditto for titanium. Yttrium (Y),
used in the familiar YIG oscillator and YAG laser, is another critical element.
Keep in mind that this chart rates elements not solely according to scarcity, but
how critical they are in processes where no other element can be substituted in
the event of a shortage. Lead (Pb) is a clear example of an element that is abundantly
available, but the materials in which it is used cannot be easily replaced with
another element...
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's
Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart."
My "Matchmaker's" design has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. My markup is only a paltry
50¢ per item - Cafe Press gets the rest of your purchase price. These would make
excellent gifts for husbands, wives, kids, significant others, and for handing out
at company events or as rewards for excellent service. It's a great way to help
support RF Cafe. Thanks...
Since 1996, ISOTEC has designed, developed
and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components
and filters for wireless service providers including non-magnetic connectors for
quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM
RF connectors components such as power dividers and directional couplers. Off-the-shelf
and customized products up to 40 GHz and our low-PIM products can meet -160 dBc
with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and
high-performance. Designs that are cost effective practical and repeatable.
Sunday the 3rd
Here is your custom made
Filter-themed crossword puzzle for April 3rd, 2022. Clues for words relevant
to the theme are marked with an asterisk (*). All RF Cafe crossword puzzles are
custom made by me, Kirt Blattenberger, and have only words and clues related to
RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics,
and other technical subjects. 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., Reginald Denny or
the Tunguska event in Siberia). The technically inclined cruciverbalists amongst
us will appreciate the effort. Enjoy!
It was a lot of work, but I finally finished
a version of the "RF & Electronics Schematic & Block Diagram Symbols" that
works well with Microsoft Office™ programs Word™, Excel™, and Power Point™.
This is an equivalent of the extensive set of amplifier, mixer, filter, switch,
connector, waveguide, digital, analog, antenna, and other commonly used symbols
for system block diagrams and schematics created for Visio™. Each of the 1,000 or
so symbols was exported individually from Visio in the EMF file format, then imported
into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or
down without becoming pixelated, so all the shapes can be resized in a document
and still look good. The imported symbols can also be UnGrouped into their original
constituent parts for editing. Check them out!
TotalTemp Technologies has more than 40 years
of combined experience providing thermal platforms.
Thermal Platforms
are available to provide temperatures between -100°C and +200°C for cryogenic cooling,
recirculating circulating coolers, temperature chambers and temperature controllers,
thermal range safety controllers, space simulation chambers, hybrid benchtop chambers,
custom systems and platforms. Manual and automated configurations for laboratory
and production environments. Please contact TotalTemp Technologies today to learn
how they can help your project.
Friday the 1st
Humor in 1933 was evidently very different
than it is today. This is part of what was in the April edition of the ARRL's QST
magazine from that year. Unlike the unannounced "April
Fools" features that may or may not appear in a given year's April issue nowadays
(the April 2022 issue of QST has a gag article on page 40 - the page 38
article is actually real), much ado was made over the gags back in the day. You
might have noticed the humor in some of the older electronics-themed comics also
sometimes invokes the "what am I missing?" response. Shown below on the left is
the gag table of contents page and on the right is the "real" table of contents.
I get the thumbing the nose by the little dude in the margin, and I get the play
on American Radio Relay League, but what the hey does "Liberian Dog-Apple Growing"
mean? Any ideas? Maybe you'll be able to appreciate the intended humor here...
"Batteries, circuitry, displays, and other
devices are increasingly made in fabric form, leading to more and more powerful
electronic textiles. Now scientists have developed an acoustic sensor consisting
of a single fiber that can turn fabrics into
microphones and speakers,
for potential applications in two-way communications, detecting the directions of
gunshots, and monitoring fetal heartbeats during pregnancy, a new study finds. The
new sensor consists of a fiber that is piezoelectric - that is, capable of converting
vibrations to electricity, and vice versa. This acoustic fiber is embedded within
a fabric consisting of a relatively soft cotton yarn, as well as a yarn roughly
as stiff as Kevlar. Previous acoustic fibers suffered from low sensitivity in air.
Moreover, fabrics normally muffle sound—for instance, carpets often help do so in
homes. In contrast, this new research actually makes use of the fabric the acoustic
fiber is woven into to help the sensor detect airborne sounds, a strategy inspired
by the complex structure of the human ear..."
"Necessity is the mother of invention,"
is a common saying that proves itself to be particularly true in times of war. World
War II launched scientists and engineers belonging to both the Axis and the
Allied powers into inventive frenzies in their efforts to hasten an end to hostilities;
of course each side also wanted to be the victor. We all know how the story ended.
Although some countries were not immediately able to capitalize on their countrymen's
technical advances, within about a decade normalized relations had been established
between former foes, and the exchange of products, services and scientific information
proceeded. Some discoveries were deemed too valuable to national security and were
therefore not divulged even, in some instances, to friendly nations. Many scientists
consider themselves to be "citizens of the world" and vehemently object to not sharing
all available knowledge out of a belief...
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. Three new
filter models have been introduced - a surface mount 536 to 632 MHz ceramic
bandpass filter, a 707 to 710 MHz / 734 to 740 MHz ceramic duplexer filter,
and a 5.5 to 23 GHz suspended stripline highpass filter with SMA connectors.
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...
Contra-polar (negative) energy is a concept
that has been investigated by many researchers beginning in the mid 19th century,
when the nature of energy was beginning to be understood from a truly scientific
perspective. Entire theories of universe and matter-antimatter creation have been
published, reviewed and refined. This article from the April 1955 edition (note
the month) of Popular Electronics reports on then-current applications of contra-polar
energy. At the time, most such work was performed in secret government laboratories
and at test ranges that were closed to the public and results banned from publication,
but since that time freedom-of-information-act requests have opened much contra-energy
research information for public access...
RF Cascade Workbook 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 (click here for screen capture). 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...
LadyBug Technologies was founded in 2004
by two microwave engineers with a passion for quality microwave test instrumentation.
Our employees offer many years experience in the design and manufacture of the worlds
best vector network analyzers, spectrum analyzers, power meters and associated components.
The management team has additional experience in optical power testing, military
radar and a variety of programming environments including LabVIEW, VEE and other
languages often used in programmatic systems. Extensive experience in a broad spectrum
of demanding measurement applications. You can be assured that our Power Sensors
are designed, built, tested and calibrated without compromise.
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.
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- Christmas-themed
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