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4 of the July 2021 homepage archives. Friday the 30th
 As were many people at the dawn of the Nuclear
Age, Radio-Craft magazine editor Hugo Gernsback predicted with the ebullience
you would expect of a technology visionary the vast role
nuclear power would play in the future of mankind. Due to the two or three month
lead time in magazine publishing in 1945, Mr. Gernsback would have written
this article entitled, "Atomic Energy and Radio" just about the time news was breaking
of the "Little Boy" and "Fat Man" thermonuclear bomb detonations. The Manhattan
Project was super-ultra-top-secret so very few people were even aware that such
an effort was in the works, so headlines with photos of the trademark mushroom cloud
over Japan were utterly shocking. The immense power released by relatively small
masses of uranium and plutonium boggled the minds of even those who understood the
physics and developed the bombs. Gernsback and others predicted fantastic peacetime
uses...
 "Fujitsu UK and partners have combined quantum-inspired
computing and AI to support the targeted removal of space debris through improved
mission planning. Fujitsu's prototype - created in collaboration with Amazon Web
Services (AWS), Astroscale UK, and Glasgow University - will improve mission planning
so that a single spacecraft can select which pieces of space debris to remove in
one mission, and at a much faster rate than is currently possible. By deciding which
debris is collected and when, Fujitsu's quantum-inspired Digital Annealer is claimed
to optimise the mission plan to determine the minimum-fuel and minimum-time required
to bring inoperable spacecrafts or satellites safely back to the disposal orbit..."
 This chapter is a milestone in your study
of electronics. Previous modules have been concerned more with individual components
of circuits than with the complete circuits as the subject. This chapter and the
other chapters of this module are concerned with the circuitry of amplifiers. While
components are discussed, the discussion of the components is not an explanation
of the working of the component itself but an explanation of the component as it
relates to the circuit. The circuits this chapter is concerned with are
Amplifiers. Amplifiers are devices that provide Amplification. That doesn't
explain much, but it does describe an amplifier if you know what amplification is
and what it is used for. What Is Amplification? Just as an amplifier is a device
that provides amplification, amplification is the process of providing an increase
in Amplitude...
 Exodus Advanced Communications, a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide, introduces the AMP2085-2.
Exodus AMP2085-2, a rugged SSPA replacing aging TWT technology. Ultra-broadband,
class A/AB design for all industry standards. 2.0-8.0 GHz, 50 W Minimum, >70 W
typical and 47 dB gain. Excellent power / gain flatness compared to TWT's.
Forward / Reflected power monitoring in dBm & Watts, VSWR, voltage / current
/ temperature sensing for superb reliability and ruggedness. The nominal weight
is 40 lbs. in a compact 3U chassis, 5.25"H x 19"W x 22"D...
 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...
 Electro-Photonics is a global supplier of
RF &
Microwave components. Their products include SMT hybrid and directional couplers,
wire bondable passive components, mounting tabs, filters, transmission lines, and
very useful test boards for evaluating components (spiral inductors, single-layer
capacitors). The Electro-Photonics team can support your small R&D design requirements
with RF & Microwave test fixtures and save you valuable design and characterization
time. Please take a moment to visit Electro-Photonics' website and see how your
project might benefit.
Thursday the 29th
 By the beginning of 1945 when most people
believed the War was all but won, the national and global attitude began to shift
from a wartime footing back to a commercial and domestic mindset. For the Axis powers
the prospect was one of shame and contrition, while knowing that unlike if they
had been the victors, Allied nations would deal harshly only with the leaders of
the aggression and destruction while showing mercy, humanity, and graciousness to
the general populations. In fact we became very good friends with Germany, Italy,
and Japan in the years immediately following their respective unconditional surrenders.
As the end of hostilities neared, information began being released by the government
about some of the previously closely guarded secrets of technical developments in
the previous half decade - such as the
radar systems covered in this October 1945 issue of Radio-Craft magazine...
 This article reporting on some of the early
applications of
atomic medicine appeared in the July 8, 1950 issue of the Saturday Evening
Post magazine. The doctors had searched without success for the brain tumor
they were sure was causing the patients severe headache, his nausea, his blurred
vision and his staggering gait. The surface of the cerebellum, the region indicated
by the symptoms, appeared perfectly normal. Nor has X-rays revealed the tumor's
whereabouts. So with great reluctance, the surgeon sewed up the skull and scalp,
wrote "brain tumor not verified" on the chart, and sent the man home. But the symptoms
persisted, became worse, and the patient, a forty-year-old stonemason whom we shall
call John Cooper, was brought back to the Massachusetts General Hospital, in Boston,
for a second try. This time the medical men enlisted the help of atomic energy.
They injected into Mr. Cooper's veins a phosphate solution containing radioactive
atoms of phosphorous...
 A
tetrode transistor is technically any transistor than contains four active terminals.
The tetrode transistor is more commonly known today as a dual base bipolar junction
transistor (BJT) or a dual gate field effect transistor (FET or MOSFET). This 1967
Electronics World magazine article reports on what was at the time a relatively
new technology. Common applications include feedback circuits for automatic gain
control (AGC), oscillators, and frequency conversion mixers...
 Royal Circuit Solutions combines decades
of manufacturing experience with the cutting edge in technology - from software
automation to the most advanced machinery in the world. Design engineers come to
us because, simply put, "we find a way to get the job done." Visit us anytime at
either our 50,000 sq.ft. shop in Hollister, CA or our newest manufacturing
facility outside of L.A. We manufacture quick-turn prototype printed circuit boards
(PCBs) - rigid, rigid-flex, and flex - for thousands of customers nation-wide, including
engineers at some of the world's biggest tech companies. Royal Circuits was founded
in 1998 - 21 years ago - to provide engineers with high-tech circuit boards incredibly
fast...
 RF Cafe's raison d'être is and always has
been to provide useful, quality content for engineers, technicians, engineering
managers, students, and hobbyists. Part of that mission is offering to post applicable
job openings. HR department employees and/or managers of hiring companies are welcome
to submit opportunities for posting at no charge (of course a gratuity will be graciously
accepted). 3rd party recruiters and temp agencies are not included so as to assure
a high quality of listings. Please read through the easy procedure to benefit from
RF Cafe's high quality visitors ...
 Aegis Power Systems is a leading supplier
of AC-DC and
DC-DC power supplies for custom and special applications. Aegis has been designing
and building highly reliable custom power supplies since 1995. They offer a complete
line of switch mode power supplies and power converters for a variety of markets
including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft,
EV, telecom, and embedded computing applications. Design and manufacture of custom
power supply solutions to meet each customer's exacting specifications. Please visit
Aegis Power Systems today.
Wednesday the 28th
 Here is another of John Comstock's crossword
puzzles from a 1960s issue of Electronics World magazine. His "Name-the-Scientist"
puzzle, as the title suggests, draws mostly on your knowledge of men who are very
familiar to anyone who has been in the electronics game for a while. There are a
few not-a-name words, but they are related to somebody's name. Mr. Comstock
must have been really fond of one guy since he and his invention appear multiple
times in various forms. I have to admit to missing 17 Down, but then at least recognizing
the name after seeing it in the answer key.
 The discussion of waveguides, up to this
point, has been concerned only with the transfer of energy from one point to another.
Many waveguide devices have been developed, however, that modify the energy in some
fashion during transit. Some devices do nothing more than change the direction of
the energy. Others have been designed to change the basic characteristics or power
level of the electromagnetic energy. This section will explain the basic operating
principles of some of the more common waveguide devices, such as
Directional Couplers, Cavity Resonators, and Hybrid Junctions. The directional
coupler is a device that provides a method of sampling energy from within a waveguide
for measurement or use in another circuit. Most couplers sample energy traveling
in one direction only. However, directional couplers can be constructed that sample
energy in both directions...
 "Electronic components face a host of challenges
while in space, from extreme temperature variation to space radiations. These harsh
conditions mean that any Commercial Off-the-Shelf (COTS) component cannot be used
for space missions. The electronic components used in making satellites must be
able to withstand a wide range of environmental challenges - from the complexities
of being launched from Earth to the extremely harsh environment of outer space.
everything RF has compiled a list of 10 trending
space-qualified RF components. Visit the new SPACE HUB on everything RF to keep
up to date with the latest on space-qualified components..."
 If you are a collector of vintage high-end
audio equipment, chances are you owned a
reel-to-reel tape player. I remember back in the 1970s that anybody wanting
to call himself an audiophile had better own a rack-mounted reel-to-reel player.
Of course the funny part is that many of those people could not afford to buy original
recordings on tape, so they would dub from an LP on a turntable or from a cassette
or, gasp, 8-track tape. This article from the August 1967 edition of Electronics
World delves into the technical aspects of magnetic tape, daring to introduce such
terms as intrinsic cohesive force, residual induction, and flux - heavy stuff for
the layman. Of course, regurgitating such terms while wowing (pun intended) their
friends with a rolling tape held to keep the subject off of whether the music being
played on a $1000 reel-to-reel player had been dubbed from a $75 cassette deck...
 When less efficient coupling is desired,
you can rotate or move the loop until it encircles a smaller number of H lines.
When the diameter of the loop is increased, its power-handling capability also increases.
The bandwidth can be increased by increasing the size of the wire used to make the
loop. When a loop is introduced into a waveguide in which an H field is present,
a
current is induced in the loop. When this condition exists, energy is removed
from the waveguide. Figure 1-40A - Loop coupling in a rectangular waveguide. Slots
or apertures are sometimes used when very loose (inefficient) coupling is desired,
as shown in figure 1-41. In this method energy enters through a small slot in the
waveguide and the E field expands into the waveguide. The E lines expand first across
the slot and then across the interior of the waveguide. Minimum reflections occur
when energy is injected or removed if the size of the slot is properly proportioned
to the frequency of the energy...
 With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils 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). Stencils 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...
 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.
Tuesday the 27th
 Here is yet another report on the work done
by
Bell Telephone Laboratories to advance the science of telecommunications. By
1945 when this appeared in Radio News magazine, Bell Labs had already been experimenting
with coaxial cable as a means of transmission for broadband voice, facsimile, and
video signals. In fact, it claims coax was used as early as 1927 to connect New
York City to Washington, D.C., and that a new loopback system simulating a 3,800-mile
run was being tested between New York City and Philadelphia. Microwave relay stations*
were also in their infancy at the time, so investigations into both modes of long
distance transmission were being explored. It is too bad the company got overzealous
and abused the customers who funded their success, resulting in a court-ordered
breakup of the monopoly in 1974. Of course company managers and lawyers quickly
figured out a way to restructure the "Baby Bells" in a manner which, taken in totality...
 "A new study by engineers at MIT, Caltech,
and ETH Zürich shows that 'nanoarchitected' materials - materials designed from
precisely patterned nanoscale structures - may be a promising route to
lightweight armor, protective coatings, blast shields, and other impact-resistant
materials. The researchers have fabricated an ultralight material made from nanometer-scale
carbon struts that give the material toughness and mechanical robustness. The team
tested the material's resilience by shooting it with microparticles at supersonic
speeds, and found that the material, which is thinner than the width of a human
hair, prevented the miniature projectiles from tearing through it..."
 There was a time when we did not take the
availability and abundance of everything for granted. Most of us have parents or
grandparents who were around during World War II that can tell stories of ration
stamps for certain food and clothing items, fuel, tires, and other things. I have
a few given to me by my grandfather. Many industries, including electronics manufacturing,
were strongly encouraged or required to dedicate all efforts toward war production.
Crosley Corporation, based in Cincinnati, Ohio, was no exception. A notice of
Crosley abandoning their 1943 line of commercial radios to make way for military
radios appeared in the September 1942 edition of Radio-Craft magazine. This is of
particular interest to me since I just completed the restoration of a 1941 vintage
Crosley 03CB floor console radio. It means I probably have one of the last pre-war
models of a Crosley radio...
 ARCTURUS is the new
flexible antenna for 5G/4G LTE/3G/2G/NB-IoT/CATM applications designed by Synzen
Precision Technology. In today's tech and electronics world, where the modern mantra
is to think bigger and make smaller, we've designed perhaps the most compact and
versatile 5G FPC antenna on the market. Measuring just 88 mm x 14 mm,
ARCTURUS can be placed internally in devices which require an integrated antenna
solution. Its ultra-small form factor doesn't compromise on performance, covering
a hugely impressive array of wideband frequencies from 617-5000 MHz. Arcturus
can be easily integrated with its "peel and stick" self-adhesive backing...
 The velocity of propagation of a wave along
a
waveguide is less than its velocity through free space (speed of light). This
lower velocity is caused by the zigzag path taken by the wavefront. The forward-progress
velocity of the wavefront in a waveguide is called Group Velocity and is somewhat
slower than the speed of light. The group velocity of energy in a waveguide is determined
by the reflection angle of the wavefronts off the "b" walls. The reflection angle
is determined by the frequency of the input energy. This basic principle is illustrated
in figures 1-28A, 1-28B, and 1-28C. As frequency is decreased, the reflection angle
decreases causing the group velocity to decrease. The opposite is also true; increasing
frequency increases the group velocity. The waveguide analyzed in the previous paragraphs
yields an electric field configuration known as the half-sine electric distribution...
 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.
Monday the 26th
 By June of 1945 when this "Postwar
Plans for the Radio Dealer" article appeared in Radio News magazine, Germany
had unconditionally surrendered at Reims, France. Japan was still holding out for
an unlikely victory and prepared for a massive Allied landing on their homeland
with the likely loss of millions of souls, but most people could feel that the end
of World War II was imminent. Accordingly, trade magazines of the day ran many
pieces discussing potential options for out-of-work servicemen. Vast amounts of
knowledge and experience had been gained in the previous half a decade, and it was
to be put to good use. Lots of men left their jobs and businesses behind for the
sake of saving the free world, and were anxious to pick up...
 "Researchers at the National Institute of
Standards and Technology (NIST) and Wavsens have developed a method for using
radio signals to create real-time images and videos of hidden and moving objects,
which could help firefighters find escape routes or victims inside buildings filled
with fire and smoke. The technique could also help track hypersonic objects such
as missiles and space debris. The new method, described June 25 in Nature Communications,
could provide critical information to help reduce deaths and injuries. Locating
and tracking first responders indoors is a prime goal for the public safety community.
Hundreds of thousands of pieces of orbiting space junk are considered dangerous
to humans and spacecraft..."
 That portion of the electromagnetic spectrum
which falls between 1000 megahertz and 100,000 megahertz is referred to as the
Microwave region. Before discussing the principles and applications of microwave
frequencies, the meaning of the term microwave as it is used in this module must
be established. On the surface, the definition of a microwave would appear to be
simple because, in electronics, the prefix "micro" normally means a millionth part
of a unit. Micro also means small, which is a relative term, and it is used in that
sense in this module. Microwave is a term loosely applied to identify electromagnetic
waves above 1000 megahertz in frequency because of the short physical wavelengths
of these frequencies. Short wavelength energy offers distinct advantages in many
applications...
 "These eyes in the sky fly above drones
and below satellites. Alphabet's enthusiasm for balloons deflated earlier this year,
when it announced that its high-altitude Internet company, Loon, could not become
commercially viable. But while the stratosphere might not be a great place to put
a cellphone tower, it could be the sweet spot for cameras, argue a host of high-tech
startups. The market for Earth-observation services from satellites is expected
to top US $4B by 2025, as orbiting cameras, radars, and other devices monitor crops,
assess infrastructure, and detect greenhouse gas emissions. Low altitude observations
from drones could be worth.
Balloons in the stratosphere, 20 kilometers above Earth (and 10 km above most
jets), split the difference..."
 By adding several shunt resistors in the
meter case, with a switch to select the desired resistor, the ammeter will be capable
of measuring several different maximum current readings or ranges. Most meter movements
in use today have sensitivities of from 5 microamperes to 1 milliampere. Figure
1-22 shows the circuit of meter switched to higher ranges, the shunt an
ammeter that uses a meter movement with a sensitivity of 100 microamperes and
shunt resistors. This ammeter has five ranges (100 microamperes; 1, 10, and 100
milliamperes; 1 ampere) selected by a switch. With the switch in the 100 microampere
position, all the current being measured will go through the meter movement. None
of the current will go through any of the shunt resistors...
 As with just about every other type of hobby
anymore, creativity and mechanical aptitude is not much of a necessity if you have
money to spend. There is such a plethora of options available for every conceivable
need to satisfy whatever degree of complexity you want your hobby to entail. The
back third of every edition of the ARRL's QST magazine is loaded with advertisements
offering antennas, radios, towers, test equipment, guy wires, insulators, cables,
connectors, soldering stations, semiconductors, tubes, nuts and bolts. It is a wonderful
world we live in if your desire is to engage in the operational aspect of a hobby
rather than the building and experimenting aspects. It was not always so. Half a
century ago the average hobbyist needed to scrounge for
components that could be "repurposed" for use as needed. Sure, there were many
sources for common components then, but even if they were available, hobbyists either
could not afford them...
 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 (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...
 Exodus Advanced Communications is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. 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. decades of combined experience in the RF field for
numerous applications including military jamming, communications, radar, EMI/EMC
and various commercial projects with all designing and manufacturing of our HPA,
MPA, and LNA products in-house.
Sunday the 25th
 This
Radio
Theme Crossword Puzzle for July 25th has many 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 --- This one is going to take a while!
 Navy Electricity and Electronics Training
Series (NEETS). A rectifier is a device that changes alternating current to a form
of direct current. The way in which this is done will be covered later in this training
series.
By connecting a rectifier to a d'Arsonval meter movement, an alternating current
measuring device is created. When ac is converted to pulsating dc, the d'Arsonval
movement will react to the average value of the pulsating dc (which is the average
value of one-half of the sine wave). Another characteristic of using a rectifier
concerns the fact that the d'Arsonval meter movement is capable of indicating current
in only one direction. If the d'Arsonval meter movement were used to indicate alternating
current without a rectifier...
 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.
Friday the 23rd
 Joseph Ryerson (see 1976 award), of the Griffiss
AFB Air Development Laboratory was thinking in 1958 when this Radio-Electronics
article appeared about a method for exploiting
gravitational waves for communication purposes long before they were finally
detected for the first time in 2015. Even today, however, we are nowhere near being
able to control gravity waves. In fact, an Earth-based system is unlikely to ever
be developed due to the extraordinarily long wavelength of various kinds of gravity
waves with periods measured in minutes, hours, days, hours, weeks, and longer. Space-based
sun-orbiting interferometer satellite pairs (LISA) are in the planning stage to
more accurately measure gravity wave. I wonder if Mr. Ryerson was/is around
to witness the gravitational wave detection? Another major topic was the DIANA Moon
Radar project where the Army Signal Corps offered to send QSL cards...
 Wayyyy.... back in 1992, RF Design
magazine (Gray Breed was editor at the time) ran a
software
contest. Those were the days when most engineers and hobbyists wrote software
in either Basic or Fortran. I happened to use Turbo Pascal, by Borland. At the time,
I was working as an RF engineer for Comsat, in Germantown, Maryland. Having done
a lot of frequency conversion designs in my previous work at General Electric, and
even more there at Comsat, I had already written a crude program to calculate mixer
spurious products, so this challenge gave me the excuse I needed to refine the user
interface and add some creature comfort features like loadable mixer spur files
and detection of spectral inversion if present. Although I did not win the grand
prize, I did win the runner-up prize. The prizes included having the following article
published in the November 1992 edition of the magazine, a couple experimenter kits
of surface mount inductors and resistors, a T-shirt, and a couple other items. Of
course, the greatest prize as far was I was concerned was having an article published
in a major magazine...
 "Researchers at Skoltech of Russia, MIT and
Nanyang Technological University of Singapore have created a neural network that
can help
tweak
semiconductor crystals in a controlled fashion to achieve superior properties
for electronics. This enables a new direction of development of next-generation
chips and solar cells by exploiting a controllable deformation that may change the
properties of a material on the fly. Materials at the nanoscale can withstand major
deformation. In what's called the strained state, they can exhibit remarkable optical,
thermal, electronic, and other properties due to a change in interatomic distances..."
RF Cafe's raison d'être is and always has
been to provide useful, quality content for engineers, technicians, engineering
managers, students, and hobbyists. Part of that mission is offering to post applicable
job openings. HR department employees and/or managers of hiring companies are welcome
to submit opportunities for posting at no charge (of course a gratuity will be graciously
accepted). 3rd party recruiters and temp agencies are not included so as to assure
a high quality of listings. Please read through the easy procedure to benefit from
RF Cafe's high quality visitors ...
 Withwave manufactures an extensive line of
metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
fully automated
4-port vector network analyzer (VNA) calibrator, between- and in-series connector
adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes &
probe positioner. Special test fixtures for calibration and multicoax cable assemblies.
Frequency ranges from DC through 110 GHz. Please contact Withwave today to
see how they can help your project succeed.
Thursday the 22nd
 According to this story in a 1945 issue of
Radio News magazine, Raytheon certainly had an ambitious plan with its
"Sky-top" network of microwave relay stations from border to border and coast
to coast. No orbiting satellites existed at the time, so purely terrestrial methods
were necessary. The basic idea was to build facilities at the peaks of the highest
mountains in the U.S. to enable high bandwidth, reliable, high quality broadcasting
of all known forms of services - television, facsimile, aircraft and nautical navigation,
telephone, emergency, et al. The funding and logistical investment would be enormous,
particularly with getting access roads, materials and electricity to all the remote
sites. Automation was to mitigate the difficulties involved in manning stations
fulltime, but there would be the need for periodic maintenance and repair. Plans
included tests for frequencies into K-band (26 GHz), which was really stretching
the limits of technology at a time when a few tens of MHz were challenging for most
applications...
 "'The current
reshoring of manufacturing, especially in the packaging industry, has benefitted
North American companies, and we think this is going to continue,' says Paul Harencak,
Vice President of Business Development & Technical Services for LPS Industries.
Reshoring accelerated during the pandemic. The closure of whole cities in China
disrupted manufacturing, as did the rise in companies making products in America
as inventories dwindled and shipping slowed. Lesson learned: Made in the USA is
the best way to ensure a reliable supply chain. 'The current reshoring of manufacturing,
especially in the packaging industry, has benefitted North American companies, and
we think this is going to continue both in the short and longer term,' said Paul
Harencak, Vice President of Business Development & Technical Services for LPS
Industries. Harencak told PlasticsToday that through his plastics converting career,
the one thing he’s learned about China is that it's a 'tenuous supplier.' In addition
to getting the product made correctly and dealing with intellectual..."
 Module 3 of the Navy Electricity and Electronics
Training Series (NEETS) series of lessons is entitled, "Introduction
to Circuit Protection, Control, and Measurement." Learning objectives include
why in-circuit meters are used, advantages of out-of-circuit meters, the way in
which a compass reacts to a conducting wire including the compass reaction to increasing
and decreasing dc and ac high and low frequencies, how a d'Arsonval meter movement
reacts to DC current, the purpose of a rectifier as used in AC meters, the meaning
of the term "damping" as it applies to meter movements and describe two methods
by which damping is accomplished, the electrical quantity measured by an ammeter...
 This
interesting - but not surprising - tidbit appeared on the IEEE website. "A public
SDR network triangulates the island as the source of mystery signals. As anti-government
protests spilled onto the streets in Cuba on July 11, something strange was happening
on the airwaves. Amateur radio operators in the U.S. found that suddenly parts of
the popular
40-meter band were being swamped with grating signals. Florida operators reported
the signals were loudest there, enough to make communication with hams in Cuba impossible.
Other operators in South America, Africa, and Europe also reported hearing the signal,
and triangulation software that anyone with a web browser can try placed the source
of the signals as emanating from Cuba..." Coming to a country near you?
 While
acoustical tiles are not exactly the stuff of RF engineering, their properties
and their effects on sound waves are analogous to RF absorbers and their effects
on electromagnetic waves. Reflections that cause multipath reception of signals
that contain the same information but are out of phase and unequal in amplitude
to the primary (direct) path seldom combine to enhance the overall signal-to-noise
ratio, so placing absorbent material in the surrounding environment is necessary
to improve signal quality. This article from a 1959 issue of Popular Electronics
goes through the process of outfitting an area with acoustical tiles and gives some
empirical test data from before and after...
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!
 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.
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.
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- Christmas-themed
items
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