"The Radio Month" was a regular feature
in Radio-Electronics magazine in the late 1940s and early 1950s. It contained
news items from around the industry and across the world. The entire two pages are
included in the included scan, but a couple items in particular stand out that are
worth mentioning. The first is announcing the soon to be available rectangular cathode
ray tubes (CRT) for television. Until then, the actual CRTs had round faces even
though the displayed image was rectangular. A 4:3 aspect ratio was the standard,
which required the tube diameter to be roughly 25% larger than the horizontal size
of the picture. In fact,
that is how TV display sizes came to be rated by their "diagonal" dimension
rather than the picture width, and the standard stuck even after rectangular tubes
were available. For instance, the 4:3 aspect ratio conveniently produces a diagonal
length of 5 (the 3:4:5 triangle), where the hypotenuse...
"The deployment of an airborne platform armed
High Energy Laser (HEL) weapon has been a major challenge for several decades.
Attempts in the past included mounting a HEL weapon in large aircraft like a Boeing
747, mainly for strategic missions like defense against tactical ballistic missiles.
Despite being very promising in their initial phases, these trial configurations
presented various technical and economic issues that resulted in their cancellation.
Recently, the focus has shifted from strategic missions to tactical missions. That
means that HEL weapons of lower power and, consequently, decreased size and weight
would be sufficient for these missions while also being more suitable for airborne
San Francisco Circuits' (SFC) specialty is
in the complex, advanced technology of PCB fabrication and assembly, producing high
quality multi-layered PCBs from elaborate layouts. Timing is everything, at least
when it comes to signal integrity in a digital system. Analog says the prevailing
wisdom is that shorter is better for using delay lines. On the digital side, numerous
signals are kept in sync with a clock. Which one is right? Learn the answer and
more about how Serpentine Routing is leading to increased performance in PCB routing
in their new article "Serpentine
Routing – Function Over Form in PCB Routing." San Francisco Circuits is a leader
in PCB fabrication and PCB assembly making sure they are on the cutting-edge of
developments in the PCB industry. From simple to complex PCBs...
Listen to the
Podcast! World War II came to an end in Europe in May of 1945, and in
the South Pacific in September of the year. By the end of 1944, Americans were becoming
confident that their fathers, sons, and husbands would soon finally be home. Manufacturers
began advertising the eminent return and availability of
consumer products that had gone out of production due to material shortages
during the war years. Advertisements ran in trade and hobby magazines as early as
1944 promising lines of goods that in many cases had not even been designed yet
or production planned. Some products being promised, however, were merely models
that were already in production before the attack on Pearl Harbor. A few publishers
refused to accept such advertisements until there was more concrete evidence that
victory was assured. In fact, Hugo Gernsback, editor and publisher of Radio-Craft
magazine, wrote a scathing piece in early 1945 admonishing manufacturers for their
overenthusiastic promise and promotion of consumer electronics prematurely...
2020 ARRL Online Auction will be
held October 15th-22nd. The preview began October 8th.
"Don't miss this opportunity to get in on the fun and bid on a variety of items
at the 15th annual ARRL Online Auction to benefit ARRL educational programs. We
suggest you read through the 'Help' section, listing bidding tips as well as the
link to our Help Desk should you need assistance. All bidders must register (your
arrl.org user ID and password will not work on the auction site). If you have registered
for a previous ARRL Online Auction, you may use the same log-in information..."
Axiom Test Equipment allows you to
test equipment, repair
test equipment, or
sell or trade test equipment. They are committed to providing superior customer
service and high quality electronic test equipment. Axiom offers customers several
practical, efficient, and cost effective solutions for their projects' TE needs
and is committed to providing superior customer service and high quality electronic
test equipment. For anyone seeking a way to offload surplus or obsolete equipment,
they offer a trade-in program or they will buy the equipment from you. Some vintage
items are available fully calibrated. Please check out Axiom Test Equipment today!
For a limited time,
RF Superstore is
offering 20% off your entire first purchase when you sign up to receive informational
e-mails. You can unsubscribe at any time afterward. The launch of RF Superstore
in 2017 marked the return of Murray Pasternack to the RF and microwave industry.
As founder and CEO of Pasternack Enterprises from 1972 to 1992, Mr. Pasternack fundamentally
changed the way RF components were sold throughout the industry. His signature catalog
greatly simplified the ordering process and became the industry standard for RF
component sales. Get better deals than ever on connectors and adapters, coaxial
cable, antennas, waveguide, surge protectors and much more.
Although I do not recall seeing a lot (none,
actually) of antennas constructed in the style of this
Holloway Electronics "Expo" model, I did a quick Web search to try finding contemporary
products exploiting the concept. The "Expo" uses a set of exponentially curved elements
to maintain a more constant separation distance between individual components in
an effort to provide better gain across the entire VHF / UHF television broadcast
bands. It seems like a really good idea on paper (no computers back in the day),
but evidently in practice using an exponent of "1" (i.e., linear like all the rest)
is good enough for acceptable reception. Any noticeable performance increase over
Axiom Test Equipment, an electronic test
equipment rental and sales company has published a new blog post entitled "Regenerative
Grid Simulators Support Real-World Testing." Prior to reading the article, I
had never given any though to how being connected to a power grid which is fed by
a large number of independent solar panels, wind turbines, and hot air from politicians
might affect the quality of electricity at my wall outlet. When multiple sources
are combined onto a common line, inevitably there will be unique artifacts (noise
spikes, harmonics, phase shifts, distortion, etc.) from each source that affects
the supplied voltage and current waveforms, even with attempts to synchronize everything.
Technically you are receiving a 60 Hz (or 50 Hz) alternating voltage source,
but its makeup can be significantly different from an otherwise pure sinewave. This
might thwart the efforts of Time Error Correction schemes implemented by electric
utility grid operators to assure a long-term frequency stability...
Popular Electronics magazine wanted
to be all things to all people - hobbyists, technicians, engineers, students, general
public) as far as electronics goes. From the very first edition in October of 1954
(two prior to this one), they included articles on circuit troubleshooting, electrical
theory, Amateur radio, DIY building projects, radio control systems for airplanes
and boats, product reviews, and much more. The first issue's "After
Class" column was "Series and Parallel Operation of Resistors" and the second
issue was entitled "Basics of Series and Parallel Circuitry." Over time, topics
delved deeper into various components and circuit configurations, then started back
again with the basics...
RF Cafe typically receives 8,000-15,000
website visits each weekday and about half that on weekends.
RF Cafe is a favorite of engineers, technicians, hobbyists, and students all
over the world. With more than 13,000 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. Advertising begins at $40/month.
The world was introduced publically in 2007
to the concept of a 3-dimensional Smith chart by Chris Zelley. In article published
in IEEE Microwave Magazine entitled, "A Spherical Representation of the
Smith Chart," the radically new concept was illustrated on the surface of a ping
pong ball using a felt-tipped pen (thumbnail at left). Inspired by the sight, Andrei
A. Muller and a small team of developers in 2013 created a version of the
3D Smith Chart in software using the Java language that allows it to execute
on any platform. In 2017, an expanded functionality commercial version of 3D Smith
Chart was released at a very modest price. A number of articles have been published
on the topic extolling the unique ability of a 3-dimensional complex impedance volume
Centric RF is a company offering from stock
various RF and Microwave coaxial
components, including attenuators, adapters, cable assemblies, terminations,
power dividers, and more. We believe in offering high performance parts from stock
at a reasonable cost. Frequency ranges of 0-110 GHz at power levels from 0.5-500
watts are available off the shelf. Order today, ship today! Centric RF is currently
looking for vendors to partner with them. Please visit Centric RF today.
Listen to the
podcast! Unless you have a tape player that you want to modify for plugging
in external speakers, the most interesting part of this "Not
Always Right" episode of Mac's Radio Service Shop will be how Mac handles a
belligerent customer. As was the topic of many articles in the days when electronics
repair shops could be found in every town, this joker accused Mac of liking to pad
bills with time charged for using his expertise and expensive test equipment. He
proved the old adage about the customer always being right usually did not apply
to those who tried to tell the repairman how to do his job. Of course if the person
could have done the repair himself, he probably would have. It reminds me of the
signs that used to hang in auto repair shops that went something like this, "Repair
rates: $30 per hour, $40 per hour with you watching, or $50 per hour with you helping."
Res-Net Microwave has published a white paper
entitled, "RF & Microwave
Terminations," which reviews important considerations such as test setups and
instrumentation and their use as terminations for RF couplers, isolators, and power
combiners / dividers. Design and use issues like voltage standing wave ratio (VWSR),
power dissipation, substrate type, temperature range, physical size and weight,
package style, and how effects of parasitic capacitance and inductance limit high
frequency operation are discussed. Input / output by means of screw-on coaxial connectors,
and soldered flanges and surface mount tabs are also covered.
Keysight Technologies announced it has expanded
PathWave Software Suite with new and enhanced capabilities. The new PathWave
solutions enable engineers to remove computational limitations across the workflow,
with cloud processing clusters, to improve designs and device reliability, while
reducing project risk. Design and test engineers are struggling with complexity
limitations that require weeks, if not months, of crunching data which can significantly
slow the development process and market introduction. Keysight's PathWave, an open,
scalable, and predictive software platform, offers fast and efficient data processing,
sharing and analysis at every stage in the product development workflow. Combining
design software, instrument control and application-specific test software, it enables
"Researchers have developed a new family
of inks that overcomes the
'coffee ring effect' to facilitate inexpensive fabrication of next-generation
electronics such as sensors, light detectors, batteries, and solar cells. A team
at the University of Cambridge spent years studying the physics of ink droplets,
which dry in a spherical pattern that's easily observed by spilling coffee on a
table and seeing the ring that forms on its surface. The team, led by Tawfique Hasan,
a professor in the university’s Cambridge Graphene Centre, combined particle tracking
in high-speed micro-photography, fluid mechanics, and different combinations of
solvents to create the new inks, which are comprised of a solution that mixes isopropyl
alcohol and 2-butanol..."
The cover of this month's Radio &
Television News magazine is part of the issue's story on performance testing
of resistors. The author was an engineer for
International Resistance Company (IRC), which is still in business as part of
TT Electronics. The massive ovens were used for load-life testing to certify resistor
products for both military and commercial uses. When required, humidity enclosures
subjected resistors to increased levels to test for insulation breakdown at high
voltage. As the article observes, since a 10-cent resistor can take down a multi-thousand
system, it is important to guarantee every component's integrity...
Since 1961, MECA
Electronics has designed and manufactured an extensive line of
RF & microwave components
for in-building, satellite, radar, radio, telemetry, mobile radio, aviation &
ATC. Attenuators, directional & hybrid couplers, isolators & circulators,
power dividers & combiners, loads, DC blocks, bias-Ts and adapters & cables.
MECA has long been the 'backbone' of high performance wired and air-interfaced networks
such as in-building applications, satellite communications, radar, radio communications,
telemetry applications, mobile radio, aviation & air traffic communications.
Unless you are into restoring and/or repairing
dial cords, you probably can't fully appreciate the humor in this short piece
from a 1953 issue of Radio-Electronics magazine. Dial cord is a type of string that
does not stretch when put under tension. It is wound around the shafts of two or
more components to keep them in step with each other. Since the advent of LED and
LCD readouts for displaying the tuned frequency, there was no need to mechanically
synchronize a sliding or rotating pointer with the position of a (usually) multi-plate
tuning capacitor. If you are/were lucky, the path of the dial cord simply wrapped
around the shaft of the tuning element (capacitor) and around the axle of a circular
tuning dial, with no pulleys or bobbins for changing the direction...
"To operate safely and reliably in outdoor
environments, electronic devices should be resistant to a wide variety of external
factors, including radiation. In fact, high-energy radiation can damage several
components of field-effect transistors (FETs) commonly used to make electronics,
including their superconducting channel, gate oxide and the insulating materials
surrounding it (e.g., isolation or substrate oxides). For several years, research
teams worldwide have thus been trying to devise strategies that could make transistors
more resistant to radiation. So far, however, this has proved to be highly challenging,
and only a few of the techniques proposed in the past have achieved promising results.
Researchers at Peking University, the Chinese Academy of Sciences and Shanghai Tech
University have recently fabricated a
radiation-hardened and repairable integrated circuit (IC) based on carbon nanotube
transistors with ion gel gates. This IC, first presented in a paper..."
RIGOL Technologies announces another significant
expansion of its RF Test Portfolio with the release of 4 new models of the
DSG800 Series RF Signal Generator. The explosion of IoT connected devices has
led to a significant increase in the amount of digital data being transmitted via
local RF interfaces. This expansion has driven a need for affordable IQ generation
capabilities. RIGOL’s new DSG800A models provide support for internal and external
IQ generation allowing engineers to quickly generate IQ traffic to simulate or validate
their designs. Available in 2.1 GHz and 3.6 GHz models with a starting
price of only $3,699 the DSG800A provides the most capable and affordable IQ generation
product on the market. Unlike some other manufacturer’s value solutions, the DSG800A
provides internal IQ modulation eliminating the need for an external IQ source...
Peter Delos, Bob Broughton, and Jon Kraft,
of Analog Devices, have published the first of a multi-part article on phased array
antenna patterns entitled, "Linear
Array Beam Characteristics and Array Factor." As has always been the case with
Analog Devices white papers, the is a good mix of equations, graphs, and explanatory
text. It begins: "With the proliferation of digital phased arrays in commercial
and aerospace and defense applications, there are many engineers working on various
aspects of the design who have limited phased array antenna familiarity. Phased
array antenna design is not new, as the theory has been well developed over decades;
however, most of the literature is intended for antenna engineers well versed in
the electromagnetic mathematics. As phased arrays begin to include more mixed signal
and digital content..."
A century from now somebody will re-publish
a story about the first human voyage to the planet Mars, and many of the folks reading
it - or at least its headline - will deem such information obsolete and not worthy
of his/her/its time reading. The same is true for many of these historical articles
I post here on RF Cafe for the benefit of those people who appreciate the efforts
and sacrifices of men and women who came before us to push back the frontiers of
Howard Hughes, whose name is familiar to fewer and fewer people these days,
was a well-known and, increasingly throughout his life, eccentric millionaire. He
made his money in, among other ventures, the aerospace industry. Hughes Aircraft
is one of his eponymous companies. Not only was Mr. Hughes an accomplished aerospace
engineer and aircraft designer, but he was an excellent pilot as well. This story
from a 1938 edition of Radio-Craft magazine reports on his bid to be the
first round-the-globe flight to be in constant contact with terra firma operators
via radio communications...
ConductRF is continually innovating and
developing new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test Cables
for labs. ConductRF makes production and test coax cable assemblies for amplitude
and phased matched VNA applications as well as standard & precision RF connectors.
Over 1,000 solutions for low PIM in-building to choose from in the iBwave component
library. They also provide custom coax solutions for applications where some standard
just won't do. A partnership with Newark assures fast, reliable access. Please visit
ConductRF today to see
how they can help your project!
October 11th's custom
Wireless Technology themed crossword puzzle contains only only words from my
custom-created lexicon related to engineering, science, mathematics, chemistry,
physics, astronomy, etc. (1,000s of them). You will never find among the words names
of politicians, mountain ranges, exotic foods or plants, movie stars, or anything
of the sort. You might, however, find someone or something in the otherwise excluded
list directly related to this puzzle's technology theme, such as Hedy Lamarr or
the Bikini Atoll, respectively. The technically inclined cruciverbalists amongst
us will appreciate the effort.
Without presenting a single equation, author
Cyrus Glickstein discusses the affects of
resistor-capacitor interaction in circuits, aka R-C time constants. This 1953
Radio-Electronics article is directed mostly toward a repair technician poking and
probing circuits while referring to schematics during troubleshooting sessions.
Being in the age of vacuum tubes without integrated circuits with built-in biasing
and interstage coupling circuits, there were plenty of discrete resistors, inductors,
and capacitors strewn throughout the chassis with point-to-point wiring and components
soldered directly to binding posts and terminal lugs on sockets, stacked wafer switches,
transformers, etc. Cold solder joints and broken wires were a fairly common occurrence...
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. 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...
RIGOL Technologies announces the new
DG2000 Series of Arbitrary Function Generators expanding their portfolio of
16 Bit Generators to satisfy the requirements of more rugged and industrial
applications. The DG2000 delivers the same performance specifications and feature
set as RIGOL's popular DG900 Series Generators. There are three DG2000 models ranging
from 50 MHz to 100 MHz making it ideal for today's mainstream requirements.
In addition to 16 Bit resolution the DG2000 includes all of the same advanced
SiFi II capabilities as the DG900. Features like Dual Tone, Harmonics and Sequencing
provide powerful generation capabilities...
If MacGyver had been around in 1935,
every episode would likely have included a
Fahnestock Clip as part of a scheme to get Angus (his first name - no kidding)
out of perilous situations. The handy little devices were very popular in electronics,
both for hobbyists and for commercial products, until fairly recently (within the
last two decades) because they provide a simple, reliable electrical connection
that does not require any tools for use - other than your finger. If you have never
heard of a Fahnestock clip, you will probably be surprised to learn what it is and
chances are you have seen one and maybe even used one. If you work in an electronics
prototyping lab area that has been around for a while, there are almost certainly
some in a parts bin somewhere or on some old...
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...
Copper Mountain Technologies develops innovative
and robust RF test and measurement solutions for engineers all over the world. Copper
Mountain's extensive line of unique form factor
Vector Network Analyzers
include an RF measurement module and a software application which runs on any Windows
PC, laptop or tablet, connecting to the measurement hardware via USB interface.
The result is a lower cost, faster, more effective test process that fits into the
modern workspace in lab, production, field and secure testing environments.
Whether you are new to the subject of noise
figure or are just looking for a quick review, this "Hot
and Cold Resistors as UHF Noise Sources" article in a 1976 issue of QST
magazine is a good source. Author Benjamin Lowe, K4VOW, does a nice job of explaining
the concept of electrical noise, and then presenting equations governing the calculation
of noise factor and noise figure. Actual numerical examples are provided to demonstrate
how the formulas work. Using this method, you can make a fair measurement of
the noise figure of a receiver without the need for expensive test equipment.
Teledyne Paradise Datacom, part of the Teledyne
Defense Electronics Group, today announced recent contract awards totaling $7.4
million to provide numerous
PowerMAX SSPA (solid state power amplifier) systems over the course of the next
two years. The largest single award of $5.9M calls for multiple PowerMAX SSPA systems
to be deployed by the customer to support Telemetry, Tracking, and Control (TT&C)
and broadband data transmission for satellite communications during an ongoing expansion
of teleport facilities. Teledyne Paradise Indoor PowerMAX SSPA System The
PowerMAX systems from Paradise are a proven, mature platform for global satcom OEMs...
"Researchers have designed a nano-electronic
circuit that can tease into existence a strange new kind of quantum 'particle.'
Its existence confirms decades of speculation about the behavior of electronic circuits
in very low temperatures and high magnetic fields - and opens the door for possible
applications in next-generation quantum computers. However, this
quasiparticle carries only a fraction of an electron's charge. It is, to be
clear, not substantively an actual single particle but rather more likely an ensemble
of electrons acting collectively in certain extreme quantum environments..."
Early investigations into RF signal
atmospheric "ducting" was reported in this 1956-era article in Popular Electronics.
Ducting effects were first noticed during World War II when Nazi broadcasts
from occupied Paris were received occasionally in London. Scientists discovered
that a small change in the humidity of the air near the surface has the effect of
trapping radio waves, a trapping process dubbed "ducting." These waves are conducted
as if they were inside of a metallic waveguide. Research by the U.S. Army Signal
Corps determined a sudden temperature rise at around 50 to 200 feet above the surface
appears to have the strongest effect...
This October edition of "The USECA Express" monthly
newsletter is undoubtedly one of the best club newsletters I have seen - and not
just because it contains an RF Cafe Crossword Puzzle! Ken Coughlin, N8KC, editor
of the publication, wrote to ask permission to use it. Event coverage - with lots
of quality color photos, club and ARRL news, contact information, training course
announcements, and a host of other good stuff is included in each edition. Note
to others: I will be glad to provide a custom crossword for your club, school, business,
that will use words relevant to your interests.
ConductRF knows many times you want to just
buy your RF assemblies to plug in to your circular D38999 connector or your VITA67
module. We offer multiple solutions for both styles of
multi-port connector all available on short lead times based on our on hand
materials stock. D38999 integrates BMA, SMPM & SMPS connectors, also other #8,
#12 & #16 coax contact solutions. VITA67.1/2 uses SMPM solutions, but the new
VITA67.3 also offers SMPS and NanoRF to support your coax. These are 100% factory
tested to exacting VSWR and loss standards because we know, Results Count!
Atenlab has been operating in Taiwan for
more than a decade, and has sold and installed hundreds chambers around the world.
Holistic, affordable Over-the-Air (OTA) measurement
systems perform comprehensive measurement and test in a controlled environment.
Compact Antenna Test Range (CATR) with one-touch operation supports multiple systems
- 2G, 3G, 4G, 5G - and major instrument brands. [M]ulti-probe OTA measurement systems
offer reduced time measurements over single-probe systems.