See Page 1 |
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4 | of the July 2024 homepage archives. Friday the 12th
 Prior to the advent of high power microwave
transmitters like the kind used in radar systems, not a lot of research was put
into how exposure by the general public to the radio waves might affect health and
well being. There was plenty of experimentation and development regarding use of
electromagnetic energy for medical and industrial purposes, but those applications
were within isolated areas with controlled access of personnel. This "Radio
Waves & Life" article in a 1960 issue of Radio-Electronics magazine
reported on the relatively new science. Little did the author know that half a century
later, human exposure to radio waves, particularly in the cellular and WiFi bands,
would be the subject of intense scrutiny. He would probably also be shocked to learn
that in early 2024, the Department of Health and Human Services' National Toxicology
Program (NTP) cancelled any further investigations into radiation exposure...
 Crane Aerospace & Electronics, a segment
of Crane Company, has launched mmW-IMA, a family of microwave assembly products.
Crane A&E has a strong heritage of delivering proven high performance microwave
solutions for over 65 years. Crane A&E's mmW-IMA product family supports
2-18 and 18-40 GHz converters and synthesizers with frequency outputs from
0.5 to 22 GHz and 29/43.56 GHz. These products are SOSA aligned in 3U
VPX chassis while exhibiting superior SWaP performance and are designed to support
rapidly growing EW, mmWave, space and other defense applications. The mmW-IMA product
line is available as EAR99 to support our international customers' needs and can
be modified to suit specific customer requirements. "Building on our strong heritage,
Crane A&E is introducing a new line of EW/mmWave and space products designed...
 After World War II had been won, the
War Assets Administration made good on the government's promise to reward citizens
for performing their patriotic civil duty whereby they participated in the collection
of recyclable material made of plastic, glass, rubber, metal, and cloth. Magazines
and newspapers had frequent coverage of bottle, metal, and tire drives showing children
pulling Radio Flyer wagons loaded to overflowing with such items gathered from trash
piles and soliciting neighborhood residents for anything that could be spared. Waste
of precious resources was a thing of shame. "Use it up, Wear it out, Make it do,
or Do without" was the slogan de jour. Ham radio operators contributed mightily
to the war effort by donating and/or selling meters, tubes, transformers, capacitor
tuning banks, and other items for the repair of battleground radios.
 This thumbnail image of a
Atwater Kent Model 776 Automobile Radio is from the AtwaterKentRadio.com website.
You can see from the picture that the entire radio was contained in a single chassis,
unlike many models of the day that had the bulky RF electronics mounted behind the
dashboard or under a seat, and the listener interface controls mounted separately
in the dashboard. Below is the Radio Service Data Sheet as it appeared in a 1936
issue of Radio-Craft magazine. It was one of six such documents that appeared
- without any description or alignment information included as is normal with the
individual, full page data sheets...
 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+ 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...
Thursday the 11th
 When Radio-Electronics magazine
owner-editor Hugo Gernsback wrote this
Interstellar Communications article in 1960, his mention of "hundreds of billions
of stars flung throughout the vastness of space" with "hundreds of millions of planets
similar to our own earth which orbit around stars like our own sun" was based on
a known universe significantly smaller than the one we now know. Once the Hubble
Space Telescope's optics were corrected in 1993, our view of the universe grew by
many orders of magnitude. Earth-based and space-based telescopes have improved significantly
since then, especially their cameras, along with post-processing of images, to where
the extents of our observable universe extends to nearly the edge of the Big Bang.
Additionally, whereas no exoplanets had been observed in 1960, a few thousand are
now documented, many of which are considered "Goldilocks Planets," believed to have
Earth-like environments. Regarding intelligent, sentient...
 Anyone who has lived in an area where the
humidity gets so low that getting an
electrostatic discharge jolt when touching a doorknob or or other isolated metallic
object, will appreciate Mac McGregor's discussion with Barney. Appropriately, it
appeared in a February issue of Popular Electronics magazine, the setting
being Mac's Service Shop's Midwestern location - a prime environment for receiving
the annoying zaps. It is a timeless subject for anyone routinely subject to exposed
high voltages of any sort - some being more dangerous than others. Most RF Cafe
visitors already know that technically, it is the amount of electric current through
the body that determines severity of electric shock, not the voltage. However...
 Withwave is a leading designer and developer
of a broad range of RF, microwave, and millimeter-wave test solutions and subsystems
with a focus on electromagnetic field analysis and signal processing. Withwave's
High-Speed, High-Density Multicoax Cable Assemblies (WMX series) provides
a wide range of multiple coax connectors and flexible cable assemblies with a choice
of 20, 40, 50, 67 & 100 GHz configurations based on precisions and superior
high frequency cabling solutions. Vertical Mount and Edge Mount options. The WMX
series is an excellent signal integrity solution for bench-top and automated test
equipment to meet increasing demands of the semiconductor and optical test industries...
 Unlike with the Mac's Service Shop episodes
that typically were published in monthly issues that temporally jived with the story
setting, the
Carl & Jerry plots did not necessarily correspond with the month in which
they appeared. For example, the February 1973 "Electrostatics at Work" story begins,
"The sparkling cold winter morning lifted the heart but numbed the fingers as Barney
sprinted quickly over the squeaking snow from his car to the service shop." To wit,
this "How to Haunt a House" story appeared in the February edition of Popular
Electronics magazine. I saved it for Halloween. As always, author John Frye
mixes technical descriptions with the storyline to lend credibility to the teens'
escapades. Modern teenagers...
 Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 280,000 times per year! 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. If you need your company
news to be seen, RF Cafe is the place to be...
Wednesday the 10th
 At the time of this "News Briefs" feature
in a 1964 Radio-Electronics magazine, satellites were a relatively new
phenomenon. Tiros VIII was already, as the nomenclature implies, the eighth
in the series of ten so-named weather satellites. Tiros, BTW, stands for
Television Infrared Observation Satellites. Tiros VIII was the first to
broadcast images to widely dispersed ground stations that used them for preparing
local forecasts and reports. It was the beginning of the live satellite images on
TV era. In other news, a new type scanning electron microscope was revealed by Westinghouse
which could produce images only 15 millionths of an inch in less than a second.
A gas laser triode was announced by Bell Telephone Laboratories, whose output could
be modulated by a control grid. This was a first step...
 "Positioned between microwaves and infrared
light, terahertz waves are key to pioneering advancements in imaging and diagnostic
technologies. A recent discovery at Tohoku University of a material that can emit
these waves more intensely promises to catalyze significant breakthroughs across
a spectrum of industries. Terahertz waves are being intensely studied by researchers
around the world seeking to understand the 'terahertz
gap.' Terahertz waves have a specific frequency that put them somewhere between
microwaves and infrared light..."
 We tend to take for granted "standards"
that have been in place and working well ever since they were instituted long ago.
Some - maybe most - standards evolve over time with user preferences driving the
end result; they tend to continue evolving. Examples include keyboard layout, advertising
and product color selection, and test instrument front panel configurations. Other
standards are driven by technology improvements. More and more often it seems, standards
are being set by industry groups that want to assure interoperability and exchangeability
amongst products and users. Often this kind of standard is driven by government
imposed regulations. Wireless communications is a prime instance of the latter.
This article is an example of a combination of standards motivators since it considers
user experience preferences with scientific research to determine how best to implement
a radio tuning dial. This was done nearly a century ago when a large...
 Werbel Microwave's WM2PD-0.5-18-S is a
wideband 2-way in-line power splitter covering the continuous bandwidth of 500 MHz
to 18 GHz in a compact enclosure measuring 4.75 x 1.00 x 0.50 inches.
The device is RoHS compliant but may be ordered specially with lead solder for military
applications. The wide bandwidth covers many of the military radio letter octave
bands in one unit. High isolation between outputs of 20 dB typical. Connectors
are stainless steel for high durability. One product covers the upper band of UHF,
L-band, S-band, C band, X-band and Ku-band. Our unique design, assembled and tested
in USA...
 Anyone other than a complete novice (Ham
pun intended) at radio and antenna work is familiar with the basics types of
directional antennas presented here. However, the universe of people knowledgeable
about such things was very small in 1935, when this article appeared in Short
Wave Craft magazine. An effort to educate operators and designers was really
just beginning. The ½-wave dipoles shown here for the transmitter are somewhat directional
at 2 dBi, and full-wave square loop antennas for receiving have a gain of around
3 dBi. However, the most significant direction-finding feature of a loop antenna
is the comparatively deep null in its radiation pattern in the plane of the wire.
That explains why direction-finding equipment, such as those on aircraft, typically
use a loop antenna. When maximum precision is needed, Yagi, log periodic, parabolic
dish, or other high gain antennas will be used...
 Amplifier Solutions Corporation (ASC) is
a manufacturer of amplifiers for commercial & military markets. ASC designs
and manufactures hybrid, surface mount flange, open carrier and connectorized amplifiers
for low, medium and high power applications using Gallium Nitride (GaN), Gallium
Arsenide (GaAs) and Silicon (Si) transistor technologies. ASC's thick film designs
operate in the frequency range of 300 kHz to 6 GHz. ASC offers thin film
designs that operate up to 20 GHz. ASC is located in an 8,000 sq.ft. facility
in the town of Telford, PA. We offer excellent customer support and take pride in
the ability to quickly react to evolving system design requirements.
 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 stencil
symbol has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks, and
more. Page templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols...
Tuesday the 9th
 If today's electronics magazines had
comics in them (which they generally do not), the themes might often include
people glued to their cellphones, monster size flat screen TVs, sentient "smart"
devices in every realm of existence, etc. In the 1960s when these three comics appeared
in Radio-Electronics magazine, amongst the most popular topics were television
repair scenarios (griping about charges, owners trying to fix their own sets, frustration
at malfunctioning sets), sophisticated stereo equipment, women's lack of understanding
about electronic things, and TV antenna installations. Being very familiar with
trends from the early days of electronics up through today, I can usually "get"
what's happening in the comics, but sometimes I'm left wondering. The page 98 and
page 112 comics are obvious enough. My guess is the gag on the page 129 comic is
not just that the repairman is waylaid with having to repair all those TVs, but
that the manager wanted to only pay for one on-site service charge. See the huge
list of comics at the bottom for other examples.
 This looks like something from a 1970s issue
of Popular Science magazine. "Imagine it's 2050 and you're on a cross-country
flight on a new type of airliner, one with no fuel on board. The plane takes off,
and you rise above the airport. Instead of climbing to cruising altitude, though,
your plane levels out and the engines quiet to a low hum. Is this normal? No one
seems to know. Anxious passengers crane their necks to get a better view out their
windows. They're all looking for one thing. Then it appears: a
massive antenna array
on the horizon. It's sending out a powerful beam of electromagnetic radiation pointed
at the underside of the plane..."
 Although you wouldn't know it from the title,
this is actually another of John T. Frye's "Mac's Radio Service Shop" stories.
MPATI stands for "Midwest
Program on Airborne Television Instruction," and was a pre-satellite-era system
for broadcasting educational programming to areas that otherwise did not experience
good quality over-the-air reception. It appeared in the May 1963 issue of Electronics
World magazine. DC-6 airplanes were outfitted with a transmitter and a hydraulically
stabilized antenna, and would fly for many hours at a time to provide rural areas
with classroom instruction via TV. Purdue University, in Indiana, played a key role
in the program. MPATI is a obvious spin-off of the Stratovision system experimented
with by Westinghouse Electric Corporation and The Glenn L. Martin Company in the
mid 1940s...
 David Goins, founder of and chief engineer
for Windfreak Technologies, has written a number of application notes pertaining
to the specification and testing of RF and microwave frequency signal generators.
His "Antenna
Beam Steering" article summarizes how RF signal generators can be an easy tool
used to start testing and understanding concepts of phased array antennas and beam
steering. Specifically, the SynthHD and SynthHD Pro RF signal generators have dual
independent channels that allow independent control of frequency, phase and amplitude
on each channel (0.01°, 100 μs switching time). If both channels are set to
the same frequency, the phase can be adjusted in fine steps across a full 360 degrees...
 Mr. Lothar Stern, of Motorola Semi, published
a 3-part series on
transistor theory in Popular Electronics magazine in 1973. This is
part 3. Part 1 introduced the basics of the bipolar transistor, and Part
2 addressed transistor circuit configurations - common emitter, common gate, common
collector, Darlington, differential - as well as presenting gain equations and delving
a bit into the physical construction of the semiconductor elements. Finally, the
author talks about the newest processes in use at the time and what was available
for low power and high power RF applications. In 1973, high power semiconductors
were just pushing past the 100 MHz barrier. Gallium arsenide (GaAs) and gallium
nitride (GaN) were still in university and corporate laboratories being prepared...
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 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...
Monday the 8th
 The 1990 edition of the Old Farmer's Almanac
(OFA) had a pretty good set of "Old
and New Mathematical Puzzles." Up until around the late 1960s, some of the puzzles
were very esoteric, often requiring one be privy to certain standards or norms.
Some were downright weird. Beginning around 2005, the OFA editors sometimes omitted
the puzzles altogether or only included simple ones, so as not to harm anyone's
feelings if he/she couldn't figure it out (seriously). Puzzles are rated for difficulty
levels 1 through 5, with 5 being the hardest. Solutions are provided for up through
difficulty level 4. Sometimes, difficulty level 5 problems are harder because they
require a lot of guesses and iterations to arrive at a solution...
 "It's
a
dark time for the telecom industry. 5G hasn't provided the ROI that everyone
needs. Layoffs are occurring across the board, and Samsung is the latest vendor
to reconfigure who's doing what. Samsung Electronics is cutting jobs in its network
division, shifting about 700 people out of its 4,000-employee network group and
into other departments, according to media reports. The move, made June 17 and reported
last week in Business Korea, is in response to the cyclical nature of the global
telecom market, which is going though a '5G winter' period that affects the entire
industry. The slowdown in 5G spending is pretty well understood across the industry
as operators shift into lower gear on the 5G deployment front..."
 Decades from now, readers will look back
at today's science magazines reporting on topics such as breakthroughs on quantum
computing and
quantum entanglement the way we now look back at articles from the middle to
latter half of the last century, and be amazed at how the understanding and exploitation
of various technologies was just getting started. This particular 1963 piece in
Electronics World magazine on quantum device is not at all related to the
two aforementioned topics; rather, it introduces the concept of discrete (quantum)
energy levels of atomic electronic orbitals and how they determine photon absorption
and emission. It is a good introduction to or refresher of the phenomenon that relates
photon energy to its wavelength via Planck's constant...
 Exodus Advanced Communications is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. We are pleased to announce
the
Exodus Model AMP2030D-LC, ideal for broadband EMI-Lab, Comm. and EW applications.
Class A/AB linear design for all modulations & industry standards. Covers 1.0
to 6.0 GHz, producing 600 W minimum, 400 W P1dB and 58 dB minimum
gain. Excellent flatness, optional monitoring parameters for Forward/Reflected power,
VSWR, voltage, current and temperature sensing for superb reliability and ruggedness.
Integrated in our compact 10U chassis weighing approximately 50 kg...
 This Radio Service Data Sheet from a 1936
issue of Radio-Craft magazine covers the
Philco Model 59, 4-tube AC Midget superheterodyne receiver. Evidently there
were at least three versions of this, a tabletop radio, a compact tabletop model
(59C), and an "Owl's Eye" model (59S). I'm not sure what the difference is. Most
- if not all - electronics servicemen had subscriptions to these magazines because
they were a ready source of not just these service sheets, but because of the extensive
articles offering advice on servicing radios and televisions. In fact, many electronics
manufacturers had a policy of supplying service data only to bona fide shops. A
large list is included at the bottom of the page of similar documents from vintage
receiver schematics, troubleshooting tips, and alignment procedures. They were originally
published in magazines...
Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 280,000 times per year! 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. If you need your company
news to be seen, RF Cafe is the place to be...
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.
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